diff options
Diffstat (limited to 'Documentation')
119 files changed, 3831 insertions, 676 deletions
diff --git a/Documentation/CodingGuidelines b/Documentation/CodingGuidelines index 45465bc0c9..e3af089ecf 100644 --- a/Documentation/CodingGuidelines +++ b/Documentation/CodingGuidelines @@ -175,6 +175,11 @@ For shell scripts specifically (not exhaustive): does not have such a problem. + - Even though "local" is not part of POSIX, we make heavy use of it + in our test suite. We do not use it in scripted Porcelains, and + hopefully nobody starts using "local" before they are reimplemented + in C ;-) + For C programs: @@ -498,7 +503,12 @@ Error Messages - Do not end error messages with a full stop. - - Do not capitalize ("unable to open %s", not "Unable to open %s") + - Do not capitalize the first word, only because it is the first word + in the message ("unable to open %s", not "Unable to open %s"). But + "SHA-3 not supported" is fine, because the reason the first word is + capitalized is not because it is at the beginning of the sentence, + but because the word would be spelled in capital letters even when + it appeared in the middle of the sentence. - Say what the error is first ("cannot open %s", not "%s: cannot open") diff --git a/Documentation/Makefile b/Documentation/Makefile index b980407059..2aae4c9cbb 100644 --- a/Documentation/Makefile +++ b/Documentation/Makefile @@ -2,6 +2,8 @@ MAN1_TXT = MAN5_TXT = MAN7_TXT = +HOWTO_TXT = +DOC_DEP_TXT = TECH_DOCS = ARTICLES = SP_ARTICLES = @@ -21,6 +23,7 @@ MAN1_TXT += gitweb.txt MAN5_TXT += gitattributes.txt MAN5_TXT += githooks.txt MAN5_TXT += gitignore.txt +MAN5_TXT += gitmailmap.txt MAN5_TXT += gitmodules.txt MAN5_TXT += gitrepository-layout.txt MAN5_TXT += gitweb.conf.txt @@ -41,6 +44,11 @@ MAN7_TXT += gittutorial-2.txt MAN7_TXT += gittutorial.txt MAN7_TXT += gitworkflows.txt +HOWTO_TXT += $(wildcard howto/*.txt) + +DOC_DEP_TXT += $(wildcard *.txt) +DOC_DEP_TXT += $(wildcard config/*.txt) + ifdef MAN_FILTER MAN_TXT = $(filter $(MAN_FILTER),$(MAN1_TXT) $(MAN5_TXT) $(MAN7_TXT)) else @@ -75,6 +83,7 @@ SP_ARTICLES += howto/rebuild-from-update-hook SP_ARTICLES += howto/rebase-from-internal-branch SP_ARTICLES += howto/keep-canonical-history-correct SP_ARTICLES += howto/maintain-git +SP_ARTICLES += howto/coordinate-embargoed-releases API_DOCS = $(patsubst %.txt,%,$(filter-out technical/api-index-skel.txt technical/api-index.txt, $(wildcard technical/api-*.txt))) SP_ARTICLES += $(API_DOCS) @@ -89,6 +98,7 @@ TECH_DOCS += technical/multi-pack-index TECH_DOCS += technical/pack-format TECH_DOCS += technical/pack-heuristics TECH_DOCS += technical/pack-protocol +TECH_DOCS += technical/parallel-checkout TECH_DOCS += technical/partial-clone TECH_DOCS += technical/protocol-capabilities TECH_DOCS += technical/protocol-common @@ -283,7 +293,7 @@ docdep_prereqs = \ mergetools-list.made $(mergetools_txt) \ cmd-list.made $(cmds_txt) -doc.dep : $(docdep_prereqs) $(wildcard *.txt) $(wildcard config/*.txt) build-docdep.perl +doc.dep : $(docdep_prereqs) $(DOC_DEP_TXT) build-docdep.perl $(QUIET_GEN)$(RM) $@+ $@ && \ $(PERL_PATH) ./build-docdep.perl >$@+ $(QUIET_STDERR) && \ mv $@+ $@ @@ -426,9 +436,9 @@ $(patsubst %.txt,%.texi,$(MAN_TXT)): %.texi : %.xml $(DOCBOOK2X_TEXI) --to-stdout $*.xml >$@+ && \ mv $@+ $@ -howto-index.txt: howto-index.sh $(wildcard howto/*.txt) +howto-index.txt: howto-index.sh $(HOWTO_TXT) $(QUIET_GEN)$(RM) $@+ $@ && \ - '$(SHELL_PATH_SQ)' ./howto-index.sh $(sort $(wildcard howto/*.txt)) >$@+ && \ + '$(SHELL_PATH_SQ)' ./howto-index.sh $(sort $(HOWTO_TXT)) >$@+ && \ mv $@+ $@ $(patsubst %,%.html,$(ARTICLES)) : %.html : %.txt @@ -437,7 +447,7 @@ $(patsubst %,%.html,$(ARTICLES)) : %.html : %.txt WEBDOC_DEST = /pub/software/scm/git/docs howto/%.html: ASCIIDOC_EXTRA += -a git-relative-html-prefix=../ -$(patsubst %.txt,%.html,$(wildcard howto/*.txt)): %.html : %.txt GIT-ASCIIDOCFLAGS +$(patsubst %.txt,%.html,$(HOWTO_TXT)): %.html : %.txt GIT-ASCIIDOCFLAGS $(QUIET_ASCIIDOC)$(RM) $@+ $@ && \ sed -e '1,/^$$/d' $< | \ $(TXT_TO_HTML) - >$@+ && \ @@ -469,7 +479,13 @@ print-man1: @for i in $(MAN1_TXT); do echo $$i; done lint-docs:: - $(QUIET_LINT)$(PERL_PATH) lint-gitlink.perl + $(QUIET_LINT)$(PERL_PATH) lint-gitlink.perl \ + $(HOWTO_TXT) $(DOC_DEP_TXT) \ + --section=1 $(MAN1_TXT) \ + --section=5 $(MAN5_TXT) \ + --section=7 $(MAN7_TXT); \ + $(PERL_PATH) lint-man-end-blurb.perl $(MAN_TXT); \ + $(PERL_PATH) lint-man-section-order.perl $(MAN_TXT); ifeq ($(wildcard po/Makefile),po/Makefile) doc-l10n install-l10n:: diff --git a/Documentation/MyFirstContribution.txt b/Documentation/MyFirstContribution.txt index 7c9a037cc2..af0a9da62e 100644 --- a/Documentation/MyFirstContribution.txt +++ b/Documentation/MyFirstContribution.txt @@ -664,7 +664,7 @@ mention the right animal somewhere: ---- test_expect_success 'runs correctly with no args and good output' ' git psuh >actual && - test_i18ngrep Pony actual + grep Pony actual ' ---- diff --git a/Documentation/RelNotes/2.17.6.txt b/Documentation/RelNotes/2.17.6.txt new file mode 100644 index 0000000000..2f181e8064 --- /dev/null +++ b/Documentation/RelNotes/2.17.6.txt @@ -0,0 +1,16 @@ +Git v2.17.6 Release Notes +========================= + +This release addresses the security issues CVE-2021-21300. + +Fixes since v2.17.5 +------------------- + + * CVE-2021-21300: + On case-insensitive file systems with support for symbolic links, + if Git is configured globally to apply delay-capable clean/smudge + filters (such as Git LFS), Git could be fooled into running + remote code during a clone. + +Credit for finding and fixing this vulnerability goes to Matheus +Tavares, helped by Johannes Schindelin. diff --git a/Documentation/RelNotes/2.18.5.txt b/Documentation/RelNotes/2.18.5.txt new file mode 100644 index 0000000000..dfb1de4ceb --- /dev/null +++ b/Documentation/RelNotes/2.18.5.txt @@ -0,0 +1,6 @@ +Git v2.18.5 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6 to address +the security issue CVE-2021-21300; see the release notes for that +version for details. diff --git a/Documentation/RelNotes/2.19.6.txt b/Documentation/RelNotes/2.19.6.txt new file mode 100644 index 0000000000..bcca6cd258 --- /dev/null +++ b/Documentation/RelNotes/2.19.6.txt @@ -0,0 +1,6 @@ +Git v2.19.6 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6 and +v2.18.5 to address the security issue CVE-2021-21300; see the +release notes for these versions for details. diff --git a/Documentation/RelNotes/2.20.5.txt b/Documentation/RelNotes/2.20.5.txt new file mode 100644 index 0000000000..1dfb784ded --- /dev/null +++ b/Documentation/RelNotes/2.20.5.txt @@ -0,0 +1,6 @@ +Git v2.20.5 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5 +and v2.19.6 to address the security issue CVE-2021-21300; see +the release notes for these versions for details. diff --git a/Documentation/RelNotes/2.21.4.txt b/Documentation/RelNotes/2.21.4.txt new file mode 100644 index 0000000000..0089dd6702 --- /dev/null +++ b/Documentation/RelNotes/2.21.4.txt @@ -0,0 +1,6 @@ +Git v2.21.4 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6 and v2.20.5 to address the security issue CVE-2021-21300; +see the release notes for these versions for details. diff --git a/Documentation/RelNotes/2.22.5.txt b/Documentation/RelNotes/2.22.5.txt new file mode 100644 index 0000000000..6b280d9321 --- /dev/null +++ b/Documentation/RelNotes/2.22.5.txt @@ -0,0 +1,7 @@ +Git v2.22.5 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, +v2.18.5, v2.19.6, v2.20.5 and v2.21.4 to address the security +issue CVE-2021-21300; see the release notes for these versions +for details. diff --git a/Documentation/RelNotes/2.23.4.txt b/Documentation/RelNotes/2.23.4.txt new file mode 100644 index 0000000000..6e5424d0da --- /dev/null +++ b/Documentation/RelNotes/2.23.4.txt @@ -0,0 +1,7 @@ +Git v2.23.4 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4 and v2.22.5 to address the security +issue CVE-2021-21300; see the release notes for these versions +for details. diff --git a/Documentation/RelNotes/2.24.4.txt b/Documentation/RelNotes/2.24.4.txt new file mode 100644 index 0000000000..4e216eec2a --- /dev/null +++ b/Documentation/RelNotes/2.24.4.txt @@ -0,0 +1,7 @@ +Git v2.24.4 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5 and v2.23.4 to address the +security issue CVE-2021-21300; see the release notes for these +versions for details. diff --git a/Documentation/RelNotes/2.25.5.txt b/Documentation/RelNotes/2.25.5.txt new file mode 100644 index 0000000000..fcb9566b15 --- /dev/null +++ b/Documentation/RelNotes/2.25.5.txt @@ -0,0 +1,7 @@ +Git v2.25.5 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4 and v2.24.4 to address +the security issue CVE-2021-21300; see the release notes for +these versions for details. diff --git a/Documentation/RelNotes/2.26.3.txt b/Documentation/RelNotes/2.26.3.txt new file mode 100644 index 0000000000..4111c38f0a --- /dev/null +++ b/Documentation/RelNotes/2.26.3.txt @@ -0,0 +1,7 @@ +Git v2.26.3 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4, v2.24.4 and v2.25.5 +to address the security issue CVE-2021-21300; see the release +notes for these versions for details. diff --git a/Documentation/RelNotes/2.27.1.txt b/Documentation/RelNotes/2.27.1.txt new file mode 100644 index 0000000000..a1e08a9f72 --- /dev/null +++ b/Documentation/RelNotes/2.27.1.txt @@ -0,0 +1,7 @@ +Git v2.27.1 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4, v2.24.4, v2.25.5 +and v2.26.3 to address the security issue CVE-2021-21300; see +the release notes for these versions for details. diff --git a/Documentation/RelNotes/2.28.1.txt b/Documentation/RelNotes/2.28.1.txt new file mode 100644 index 0000000000..8484c8297c --- /dev/null +++ b/Documentation/RelNotes/2.28.1.txt @@ -0,0 +1,7 @@ +Git v2.28.1 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4, v2.24.4, v2.25.5, +v2.26.3 and v2.27.1 to address the security issue CVE-2021-21300; +see the release notes for these versions for details. diff --git a/Documentation/RelNotes/2.29.3.txt b/Documentation/RelNotes/2.29.3.txt new file mode 100644 index 0000000000..e10eedb35a --- /dev/null +++ b/Documentation/RelNotes/2.29.3.txt @@ -0,0 +1,8 @@ +Git v2.29.3 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, +v2.18.5, v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4, v2.24.4, +v2.25.5, v2.26.3, v2.27.1 and v2.28.1 to address the security +issue CVE-2021-21300; see the release notes for these versions +for details. diff --git a/Documentation/RelNotes/2.30.2.txt b/Documentation/RelNotes/2.30.2.txt new file mode 100644 index 0000000000..bada398501 --- /dev/null +++ b/Documentation/RelNotes/2.30.2.txt @@ -0,0 +1,8 @@ +Git v2.30.2 Release Notes +========================= + +This release merges up the fixes that appear in v2.17.6, v2.18.5, +v2.19.6, v2.20.5, v2.21.4, v2.22.5, v2.23.4, v2.24.4, v2.25.5, +v2.26.3, v2.27.1, v2.28.1 and v2.29.3 to address the security +issue CVE-2021-21300; see the release notes for these versions +for details. diff --git a/Documentation/RelNotes/2.31.0.txt b/Documentation/RelNotes/2.31.0.txt new file mode 100644 index 0000000000..cf0c7d8d40 --- /dev/null +++ b/Documentation/RelNotes/2.31.0.txt @@ -0,0 +1,365 @@ +Git 2.31 Release Notes +====================== + +Updates since v2.30 +------------------- + +Backward incompatible and other important changes + + * The "pack-redundant" command, which has been left stale with almost + unusable performance issues, now warns loudly when it gets used, as + we no longer want to recommend its use (instead just "repack -d" + instead). + + * The development community has adopted Contributor Covenant v2.0 to + update from v1.4 that we have been using. + + * The support for deprecated PCRE1 library has been dropped. + + * Fixes for CVE-2021-21300 in Git 2.30.2 (and earlier) is included. + + +UI, Workflows & Features + + * The "--format=%(trailers)" mechanism gets enhanced to make it + easier to design output for machine consumption. + + * When a user does not tell "git pull" to use rebase or merge, the + command gives a loud message telling a user to choose between + rebase or merge but creates a merge anyway, forcing users who would + want to rebase to redo the operation. Fix an early part of this + problem by tightening the condition to give the message---there is + no reason to stop or force the user to choose between rebase or + merge if the history fast-forwards. + + * The configuration variable 'core.abbrev' can be set to 'no' to + force no abbreviation regardless of the hash algorithm. + + * "git rev-parse" can be explicitly told to give output as absolute + or relative path with the `--path-format=(absolute|relative)` option. + + * Bash completion (in contrib/) update to make it easier for + end-users to add completion for their custom "git" subcommands. + + * "git maintenance" learned to drive scheduled maintenance on + platforms whose native scheduling methods are not 'cron'. + + * After expiring a reflog and making a single commit, the reflog for + the branch would record a single entry that knows both @{0} and + @{1}, but we failed to answer "what commit were we on?", i.e. @{1} + + * "git bundle" learns "--stdin" option to read its refs from the + standard input. Also, it now does not lose refs whey they point + at the same object. + + * "git log" learned a new "--diff-merges=<how>" option. + + * "git ls-files" can and does show multiple entries when the index is + unmerged, which is a source for confusion unless -s/-u option is in + use. A new option --deduplicate has been introduced. + + * `git worktree list` now annotates worktrees as prunable, shows + locked and prunable attributes in --porcelain mode, and gained + a --verbose option. + + * "git clone" tries to locally check out the branch pointed at by + HEAD of the remote repository after it is done, but the protocol + did not convey the information necessary to do so when copying an + empty repository. The protocol v2 learned how to do so. + + * There are other ways than ".." for a single token to denote a + "commit range", namely "<rev>^!" and "<rev>^-<n>", but "git + range-diff" did not understand them. + + * The "git range-diff" command learned "--(left|right)-only" option + to show only one side of the compared range. + + * "git mergetool" feeds three versions (base, local and remote) of + a conflicted path unmodified. The command learned to optionally + prepare these files with unconflicted parts already resolved. + + * The .mailmap is documented to be read only from the root level of a + working tree, but a stray file in a bare repository also was read + by accident, which has been corrected. + + * "git maintenance" tool learned a new "pack-refs" maintenance task. + + * The error message given when a configuration variable that is + expected to have a boolean value has been improved. + + * Signed commits and tags now allow verification of objects, whose + two object names (one in SHA-1, the other in SHA-256) are both + signed. + + * "git rev-list" command learned "--disk-usage" option. + + * "git {diff,log} --{skip,rotate}-to=<path>" allows the user to + discard diff output for early paths or move them to the end of the + output. + + * "git difftool" learned "--skip-to=<path>" option to restart an + interrupted session from an arbitrary path. + + * "git grep" has been tweaked to be limited to the sparse checkout + paths. + + * "git rebase --[no-]fork-point" gained a configuration variable + rebase.forkPoint so that users do not have to keep specifying a + non-default setting. + + +Performance, Internal Implementation, Development Support etc. + + * A 3-year old test that was not testing anything useful has been + corrected. + + * Retire more names with "sha1" in it. + + * The topological walk codepath is covered by new trace2 stats. + + * Update the Code-of-conduct to version 2.0 from the upstream (we've + been using version 1.4). + + * "git mktag" validates its input using its own rules before writing + a tag object---it has been updated to share the logic with "git + fsck". + + * Two new ways to feed configuration variable-value pairs via + environment variables have been introduced, and the way + GIT_CONFIG_PARAMETERS encodes variable/value pairs has been tweaked + to make it more robust. + + * Tests have been updated so that they do not to get affected by the + name of the default branch "git init" creates. + + * "git fetch" learns to treat ref updates atomically in all-or-none + fashion, just like "git push" does, with the new "--atomic" option. + + * The peel_ref() API has been replaced with peel_iterated_oid(). + + * The .use_shell flag in struct child_process that is passed to + run_command() API has been clarified with a bit more documentation. + + * Document, clean-up and optimize the code around the cache-tree + extension in the index. + + * The ls-refs protocol operation has been optimized to narrow the + sub-hierarchy of refs/ it walks to produce response. + + * When removing many branches and tags, the code used to do so one + ref at a time. There is another API it can use to delete multiple + refs, and it makes quite a lot of performance difference when the + refs are packed. + + * The "pack-objects" command needs to iterate over all the tags when + automatic tag following is enabled, but it actually iterated over + all refs and then discarded everything outside "refs/tags/" + hierarchy, which was quite wasteful. + + * A perf script was made more portable. + + * Our setting of GitHub CI test jobs were a bit too eager to give up + once there is even one failure found. Tweak the knob to allow + other jobs keep running even when we see a failure, so that we can + find more failures in a single run. + + * We've carried compatibility codepaths for compilers without + variadic macros for quite some time, but the world may be ready for + them to be removed. Force compilation failure on exotic platforms + where variadic macros are not available to find out who screams in + such a way that we can easily revert if it turns out that the world + is not yet ready. + + * Code clean-up to ensure our use of hashtables using object names as + keys use the "struct object_id" objects, not the raw hash values. + + * Lose the debugging aid that may have been useful in the past, but + no longer is, in the "grep" codepaths. + + * Some pretty-format specifiers do not need the data in commit object + (e.g. "%H"), but we were over-eager to load and parse it, which has + been made even lazier. + + * Get rid of "GETTEXT_POISON" support altogether, which may or may + not be controversial. + + * Introduce an on-disk file to record revindex for packdata, which + traditionally was always created on the fly and only in-core. + + * The commit-graph learned to use corrected commit dates instead of + the generation number to help topological revision traversal. + + * Piecemeal of rewrite of "git bisect" in C continues. + + * When a pager spawned by us exited, the trace log did not record its + exit status correctly, which has been corrected. + + * Removal of GIT_TEST_GETTEXT_POISON continues. + + * The code to implement "git merge-base --independent" was poorly + done and was kept from the very beginning of the feature. + + * Preliminary changes to fsmonitor integration. + + * Performance improvements for rename detection. + + * The common code to deal with "chunked file format" that is shared + by the multi-pack-index and commit-graph files have been factored + out, to help codepaths for both filetypes to become more robust. + + * The approach to "fsck" the incoming objects in "index-pack" is + attractive for performance reasons (we have them already in core, + inflated and ready to be inspected), but fundamentally cannot be + applied fully when we receive more than one pack stream, as a tree + object in one pack may refer to a blob object in another pack as + ".gitmodules", when we want to inspect blobs that are used as + ".gitmodules" file, for example. Teach "index-pack" to emit + objects that must be inspected later and check them in the calling + "fetch-pack" process. + + * The logic to handle "trailer" related placeholders in the + "--format=" mechanisms in the "log" family and "for-each-ref" + family is getting unified. + + * Raise the buffer size used when writing the index file out from + (obviously too small) 8kB to (clearly sufficiently large) 128kB. + + * It is reported that open() on some platforms (e.g. macOS Big Sur) + can return EINTR even though our timers are set up with SA_RESTART. + A workaround has been implemented and enabled for macOS to rerun + open() transparently from the caller when this happens. + + +Fixes since v2.30 +----------------- + + * Diagnose command line error of "git rebase" early. + + * Clean up option descriptions in "git cmd --help". + + * "git stash" did not work well in a sparsely checked out working + tree. + + * Some tests expect that "ls -l" output has either '-' or 'x' for + group executable bit, but setgid bit can be inherited from parent + directory and make these fields 'S' or 's' instead, causing test + failures. + + * "git for-each-repo --config=<var> <cmd>" should not run <cmd> for + any repository when the configuration variable <var> is not defined + even once. + + * Fix 2.29 regression where "git mergetool --tool-help" fails to list + all the available tools. + + * Fix for procedure to building CI test environment for mac. + + * The implementation of "git branch --sort" wrt the detached HEAD + display has always been hacky, which has been cleaned up. + + * Newline characters in the host and path part of git:// URL are + now forbidden. + + * "git diff" showed a submodule working tree with untracked cruft as + "Submodule commit <objectname>-dirty", but a natural expectation is + that the "-dirty" indicator would align with "git describe --dirty", + which does not consider having untracked files in the working tree + as source of dirtiness. The inconsistency has been fixed. + + * When more than one commit with the same patch ID appears on one + side, "git log --cherry-pick A...B" did not exclude them all when a + commit with the same patch ID appears on the other side. Now it + does. + + * Documentation for "git fsck" lost stale bits that has become + incorrect. + + * Doc fix for packfile URI feature. + + * When "git rebase -i" processes "fixup" insn, there is no reason to + clean up the commit log message, but we did the usual stripspace + processing. This has been corrected. + (merge f7d42ceec5 js/rebase-i-commit-cleanup-fix later to maint). + + * Fix in passing custom args from "git clone" to "upload-pack" on the + other side. + (merge ad6b5fefbd jv/upload-pack-filter-spec-quotefix later to maint). + + * The command line completion (in contrib/) completed "git branch -d" + with branch names, but "git branch -D" offered tagnames in addition, + which has been corrected. "git branch -M" had the same problem. + (merge 27dc071b9a jk/complete-branch-force-delete later to maint). + + * When commands are started from a subdirectory, they may have to + compare the path to the subdirectory (called prefix and found out + from $(pwd)) with the tracked paths. On macOS, $(pwd) and + readdir() yield decomposed path, while the tracked paths are + usually normalized to the precomposed form, causing mismatch. This + has been fixed by taking the same approach used to normalize the + command line arguments. + (merge 5c327502db tb/precompose-prefix-too later to maint). + + * Even though invocations of "die()" were logged to the trace2 + system, "BUG()"s were not, which has been corrected. + (merge 0a9dde4a04 jt/trace2-BUG later to maint). + + * "git grep --untracked" is meant to be "let's ALSO find in these + files on the filesystem" when looking for matches in the working + tree files, and does not make any sense if the primary search is + done against the index, or the tree objects. The "--cached" and + "--untracked" options have been marked as mutually incompatible. + (merge 0c5d83b248 mt/grep-cached-untracked later to maint). + + * Fix "git fsck --name-objects" which apparently has not been used by + anybody who is motivated enough to report breakage. + (merge e89f89361c js/fsck-name-objects-fix later to maint). + + * Avoid individual tests in t5411 from getting affected by each other + by forcing them to use separate output files during the test. + (merge 822ee894f6 jx/t5411-unique-filenames later to maint). + + * Test to make sure "git rev-parse one-thing one-thing" gives + the same thing twice (when one-thing is --since=X). + (merge a5cdca4520 ew/rev-parse-since-test later to maint). + + * When certain features (e.g. grafts) used in the repository are + incompatible with the use of the commit-graph, we used to silently + turned commit-graph off; we now tell the user what we are doing. + (merge c85eec7fc3 js/commit-graph-warning later to maint). + + * Objects that lost references can be pruned away, even when they + have notes attached to it (and these notes will become dangling, + which in turn can be pruned with "git notes prune"). This has been + clarified in the documentation. + (merge fa9ab027ba mz/doc-notes-are-not-anchors later to maint). + + * The error codepath around the "--temp/--prefix" feature of "git + checkout-index" has been improved. + (merge 3f7ba60350 mt/checkout-index-corner-cases later to maint). + + * The "git maintenance register" command had trouble registering bare + repositories, which had been corrected. + + * A handful of multi-word configuration variable names in + documentation that are spelled in all lowercase have been corrected + to use the more canonical camelCase. + (merge 7dd0eaa39c dl/doc-config-camelcase later to maint). + + * "git push $there --delete ''" should have been diagnosed as an + error, but instead turned into a matching push, which has been + corrected. + (merge 20e416409f jc/push-delete-nothing later to maint). + + * Test script modernization. + (merge 488acf15df sv/t7001-modernize later to maint). + + * An under-allocation for the untracked cache data has been corrected. + (merge 6347d649bc jh/untracked-cache-fix later to maint). + + * Other code cleanup, docfix, build fix, etc. + (merge e3f5da7e60 sg/t7800-difftool-robustify later to maint). + (merge 9d336655ba js/doc-proto-v2-response-end later to maint). + (merge 1b5b8cf072 jc/maint-column-doc-typofix later to maint). + (merge 3a837b58e3 cw/pack-config-doc later to maint). + (merge 01168a9d89 ug/doc-commit-approxidate later to maint). + (merge b865734760 js/params-vs-args later to maint). diff --git a/Documentation/RelNotes/2.31.1.txt b/Documentation/RelNotes/2.31.1.txt new file mode 100644 index 0000000000..f9b06b8e1b --- /dev/null +++ b/Documentation/RelNotes/2.31.1.txt @@ -0,0 +1,27 @@ +Git 2.31.1 Release Notes +======================== + +Fixes since v2.31 +----------------- + + * The fsmonitor interface read from its input without making sure + there is something to read from. This bug is new in 2.31 + timeframe. + + * The data structure used by fsmonitor interface was not properly + duplicated during an in-core merge, leading to use-after-free etc. + + * "git bisect" reimplemented more in C during 2.30 timeframe did not + take an annotated tag as a good/bad endpoint well. This regression + has been corrected. + + * Fix macros that can silently inject unintended null-statements. + + * CALLOC_ARRAY() macro replaces many uses of xcalloc(). + + * Update insn in Makefile comments to run fuzz-all target. + + * Fix a corner case bug in "git mv" on case insensitive systems, + which was introduced in 2.29 timeframe. + +Also contains various documentation updates and code clean-ups. diff --git a/Documentation/RelNotes/2.32.0.txt b/Documentation/RelNotes/2.32.0.txt new file mode 100644 index 0000000000..ed590a7b56 --- /dev/null +++ b/Documentation/RelNotes/2.32.0.txt @@ -0,0 +1,411 @@ +Git 2.32 Release Notes +====================== + +Backward compatibility notes +---------------------------- + + * ".gitattributes", ".gitignore", and ".mailmap" files that are + symbolic links are ignored. + + * "git apply --3way" used to first attempt a straight application, + and only fell back to the 3-way merge algorithm when the stright + application failed. Starting with this version, the command will + first try the 3-way merge algorithm and only when it fails (either + resulting with conflict or the base versions of blobs are missing), + falls back to the usual patch application. + + +Updates since v2.31 +------------------- + +UI, Workflows & Features + + * It does not make sense to make ".gitattributes", ".gitignore" and + ".mailmap" symlinks, as they are supposed to be usable from the + object store (think: bare repositories where HEAD:.mailmap etc. are + used). When these files are symbolic links, we used to read the + contents of the files pointed by them by mistake, which has been + corrected. + + * "git stash show" learned to optionally show untracked part of the + stash. + + * "git log --format='...'" learned "%(describe)" placeholder. + + * "git repack" so far has been only capable of repacking everything + under the sun into a single pack (or split by size). A cleverer + strategy to reduce the cost of repacking a repository has been + introduced. + + * The http codepath learned to let the credential layer to cache the + password used to unlock a certificate that has successfully been + used. + + * "git commit --fixup=<commit>", which was to tweak the changes made + to the contents while keeping the original log message intact, + learned "--fixup=(amend|reword):<commit>", that can be used to + tweak both the message and the contents, and only the message, + respectively. + + * "git send-email" learned to honor the core.hooksPath configuration. + + * "git format-patch -v<n>" learned to allow a reroll count that is + not an integer. + + * "git commit" learned "--trailer <key>[=<value>]" option; together + with the interpret-trailers command, this will make it easier to + support custom trailers. + + * "git clone --reject-shallow" option fails the clone as soon as we + notice that we are cloning from a shallow repository. + + * A configuration variable has been added to force tips of certain + refs to be given a reachability bitmap. + + * "gitweb" learned "e-mail privacy" feature to redact strings that + look like e-mail addresses on various pages. + + * "git apply --3way" has always been "to fall back to 3-way merge + only when straight application fails". Swap the order of falling + back so that 3-way is always attempted first (only when the option + is given, of course) and then straight patch application is used as + a fallback when it fails. + + * "git apply" now takes "--3way" and "--cached" at the same time, and + work and record results only in the index. + + * The command line completion (in contrib/) has learned that + CHERRY_PICK_HEAD is a possible pseudo-ref. + + * Userdiff patterns for "Scheme" has been added. + + * "git log" learned "--diff-merges=<style>" option, with an + associated configuration variable log.diffMerges. + + * "git log --format=..." placeholders learned %ah/%ch placeholders to + request the --date=human output. + + * Replace GIT_CONFIG_NOSYSTEM mechanism to decline from reading the + system-wide configuration file with GIT_CONFIG_SYSTEM that lets + users specify from which file to read the system-wide configuration + (setting it to an empty file would essentially be the same as + setting NOSYSTEM), and introduce GIT_CONFIG_GLOBAL to override the + per-user configuration in $HOME/.gitconfig. + + * "git add" and "git rm" learned not to touch those paths that are + outside of sparse checkout. + + * "git rev-list" learns the "--filter=object:type=<type>" option, + which can be used to exclude objects of the given kind from the + packfile generated by pack-objects. + + * The command line completion (in contrib/) for "git stash" has been + updated. + + * "git subtree" updates. + + * It is now documented that "format-patch" skips merges. + + * Options to "git pack-objects" that take numeric values like + --window and --depth should not accept negative values; the input + validation has been tightened. + + * The way the command line specified by the trailer.<token>.command + configuration variable receives the end-user supplied value was + both error prone and misleading. An alternative to achieve the + same goal in a safer and more intuitive way has been added, as + the trailer.<token>.cmd configuration variable, to replace it. + + * "git add -i --dry-run" does not dry-run, which was surprising. The + combination of options has taught to error out. + + * "git push" learns to discover common ancestor with the receiving + end over protocol v2. This will hopefully make "git push" as + efficient as "git fetch" in avoiding objects from getting + transferred unnecessarily. + + * "git mailinfo" (hence "git am") learned the "--quoted-cr" option to + control how lines ending with CRLF wrapped in base64 or qp are + handled. + + +Performance, Internal Implementation, Development Support etc. + + * Rename detection rework continues. + + * GIT_TEST_FAIL_PREREQS is a mechanism to skip test pieces with + prerequisites to catch broken tests that depend on the side effects + of optional pieces, but did not work at all when negative + prerequisites were involved. + (merge 27d578d904 jk/fail-prereq-testfix later to maint). + + * "git diff-index" codepath has been taught to trust fsmonitor status + to reduce number of lstat() calls. + (merge 7e5aa13d2c nk/diff-index-fsmonitor later to maint). + + * Reorganize Makefile to allow building git.o and other essential + objects without extra stuff needed only for testing. + + * Preparatory API changes for parallel checkout. + + * A simple IPC interface gets introduced to build services like + fsmonitor on top. + + * Fsck API clean-up. + + * SECURITY.md that is facing individual contributors and end users + has been introduced. Also a procedure to follow when preparing + embargoed releases has been spelled out. + (merge 09420b7648 js/security-md later to maint). + + * Optimize "rev-list --use-bitmap-index --objects" corner case that + uses negative tags as the stopping points. + + * CMake update for vsbuild. + + * An on-disk reverse-index to map the in-pack location of an object + back to its object name across multiple packfiles is introduced. + + * Generate [ec]tags under $(QUIET_GEN). + + * Clean-up codepaths that implements "git send-email --validate" + option and improves the message from it. + + * The last remnant of gettext-poison has been removed. + + * The test framework has been taught to optionally turn the default + merge strategy to "ort" throughout the system where we use + three-way merges internally, like cherry-pick, rebase etc., + primarily to enhance its test coverage (the strategy has been + available as an explicit "-s ort" choice). + + * A bit of code clean-up and a lot of test clean-up around userdiff + area. + + * Handling of "promisor packs" that allows certain objects to be + missing and lazily retrievable has been optimized (a bit). + + * When packet_write() fails, we gave an extra error message + unnecessarily, which has been corrected. + + * The checkout machinery has been taught to perform the actual + write-out of the files in parallel when able. + + * Show errno in the trace output in the error codepath that calls + read_raw_ref method. + + * Effort to make the command line completion (in contrib/) safe with + "set -u" continues. + + * Tweak a few tests for "log --format=..." that show timestamps in + various formats. + + * The reflog expiry machinery has been taught to emit trace events. + + * Over-the-wire protocol learns a new request type to ask for object + sizes given a list of object names. + + +Fixes since v2.31 +----------------- + + * The fsmonitor interface read from its input without making sure + there is something to read from. This bug is new in 2.31 + timeframe. + + * The data structure used by fsmonitor interface was not properly + duplicated during an in-core merge, leading to use-after-free etc. + + * "git bisect" reimplemented more in C during 2.30 timeframe did not + take an annotated tag as a good/bad endpoint well. This regression + has been corrected. + + * Fix macros that can silently inject unintended null-statements. + + * CALLOC_ARRAY() macro replaces many uses of xcalloc(). + + * Update insn in Makefile comments to run fuzz-all target. + + * Fix a corner case bug in "git mv" on case insensitive systems, + which was introduced in 2.29 timeframe. + + * We had a code to diagnose and die cleanly when a required + clean/smudge filter is missing, but an assert before that + unnecessarily fired, hiding the end-user facing die() message. + (merge 6fab35f748 mt/cleanly-die-upon-missing-required-filter later to maint). + + * Update C code that sets a few configuration variables when a remote + is configured so that it spells configuration variable names in the + canonical camelCase. + (merge 0f1da600e6 ab/remote-write-config-in-camel-case later to maint). + + * A new configuration variable has been introduced to allow choosing + which version of the generation number gets used in the + commit-graph file. + (merge 702110aac6 ds/commit-graph-generation-config later to maint). + + * Perf test update to work better in secondary worktrees. + (merge 36e834abc1 jk/perf-in-worktrees later to maint). + + * Updates to memory allocation code around the use of pcre2 library. + (merge c1760352e0 ab/grep-pcre2-allocfix later to maint). + + * "git -c core.bare=false clone --bare ..." would have segfaulted, + which has been corrected. + (merge 75555676ad bc/clone-bare-with-conflicting-config later to maint). + + * When "git checkout" removes a path that does not exist in the + commit it is checking out, it wasn't careful enough not to follow + symbolic links, which has been corrected. + (merge fab78a0c3d mt/checkout-remove-nofollow later to maint). + + * A few option description strings started with capital letters, + which were corrected. + (merge 5ee90326dc cc/downcase-opt-help later to maint). + + * Plug or annotate remaining leaks that trigger while running the + very basic set of tests. + (merge 68ffe095a2 ah/plugleaks later to maint). + + * The hashwrite() API uses a buffering mechanism to avoid calling + write(2) too frequently. This logic has been refactored to be + easier to understand. + (merge ddaf1f62e3 ds/clarify-hashwrite later to maint). + + * "git cherry-pick/revert" with or without "--[no-]edit" did not spawn + the editor as expected (e.g. "revert --no-edit" after a conflict + still asked to edit the message), which has been corrected. + (merge 39edfd5cbc en/sequencer-edit-upon-conflict-fix later to maint). + + * "git daemon" has been tightened against systems that take backslash + as directory separator. + (merge 9a7f1ce8b7 rs/daemon-sanitize-dir-sep later to maint). + + * A NULL-dereference bug has been corrected in an error codepath in + "git for-each-ref", "git branch --list" etc. + (merge c685450880 jk/ref-filter-segfault-fix later to maint). + + * Streamline the codepath to fix the UTF-8 encoding issues in the + argv[] and the prefix on macOS. + (merge c7d0e61016 tb/precompose-prefix-simplify later to maint). + + * The command-line completion script (in contrib/) had a couple of + references that would have given a warning under the "-u" (nounset) + option. + (merge c5c0548d79 vs/completion-with-set-u later to maint). + + * When "git pack-objects" makes a literal copy of a part of existing + packfile using the reachability bitmaps, its update to the progress + meter was broken. + (merge 8e118e8490 jk/pack-objects-bitmap-progress-fix later to maint). + + * The dependencies for config-list.h and command-list.h were broken + when the former was split out of the latter, which has been + corrected. + (merge 56550ea718 sg/bugreport-fixes later to maint). + + * "git push --quiet --set-upstream" was not quiet when setting the + upstream branch configuration, which has been corrected. + (merge f3cce896a8 ow/push-quiet-set-upstream later to maint). + + * The prefetch task in "git maintenance" assumed that "git fetch" + from any remote would fetch all its local branches, which would + fetch too much if the user is interested in only a subset of + branches there. + (merge 32f67888d8 ds/maintenance-prefetch-fix later to maint). + + * Clarify that pathnames recorded in Git trees are most often (but + not necessarily) encoded in UTF-8. + (merge 9364bf465d ab/pathname-encoding-doc later to maint). + + * "git --config-env var=val cmd" weren't accepted (only + --config-env=var=val was). + (merge c331551ccf ps/config-env-option-with-separate-value later to maint). + + * When the reachability bitmap is in effect, the "do not lose + recently created objects and those that are reachable from them" + safety to protect us from races were disabled by mistake, which has + been corrected. + (merge 2ba582ba4c jk/prune-with-bitmap-fix later to maint). + + * Cygwin pathname handling fix. + (merge bccc37fdc7 ad/cygwin-no-backslashes-in-paths later to maint). + + * "git rebase --[no-]reschedule-failed-exec" did not work well with + its configuration variable, which has been corrected. + (merge e5b32bffd1 ab/rebase-no-reschedule-failed-exec later to maint). + + * Portability fix for command line completion script (in contrib/). + (merge f2acf763e2 si/zsh-complete-comment-fix later to maint). + + * "git repack -A -d" in a partial clone unnecessarily loosened + objects in promisor pack. + + * "git bisect skip" when custom words are used for new/old did not + work, which has been corrected. + + * A few variants of informational message "Already up-to-date" has + been rephrased. + (merge ad9322da03 js/merge-already-up-to-date-message-reword later to maint). + + * "git submodule update --quiet" did not propagate the quiet option + down to underlying "git fetch", which has been corrected. + (merge 62af4bdd42 nc/submodule-update-quiet later to maint). + + * Document that our test can use "local" keyword. + (merge a84fd3bcc6 jc/test-allows-local later to maint). + + * The word-diff mode has been taught to work better with a word + regexp that can match an empty string. + (merge 0324e8fc6b pw/word-diff-zero-width-matches later to maint). + + * "git p4" learned to find branch points more efficiently. + (merge 6b79818bfb jk/p4-locate-branch-point-optim later to maint). + + * When "git update-ref -d" removes a ref that is packed, it left + empty directories under $GIT_DIR/refs/ for + (merge 5f03e5126d wc/packed-ref-removal-cleanup later to maint). + + * "git clean" and "git ls-files -i" had confusion around working on + or showing ignored paths inside an ignored directory, which has + been corrected. + (merge b548f0f156 en/dir-traversal later to maint). + + * The handling of "%(push)" formatting element of "for-each-ref" and + friends was broken when the same codepath started handling + "%(push:<what>)", which has been corrected. + (merge 1e1c4c5eac zh/ref-filter-push-remote-fix later to maint). + + * The bash prompt script (in contrib/) did not work under "set -u". + (merge 5c0cbdb107 en/prompt-under-set-u later to maint). + + * The "chainlint" feature in the test framework is a handy way to + catch common mistakes in writing new tests, but tends to get + expensive. An knob to selectively disable it has been introduced + to help running tests that the developer has not modified. + (merge 2d86a96220 jk/test-chainlint-softer later to maint). + + * Other code cleanup, docfix, build fix, etc. + (merge f451960708 dl/cat-file-doc-cleanup later to maint). + (merge 12604a8d0c sv/t9801-test-path-is-file-cleanup later to maint). + (merge ea7e63921c jr/doc-ignore-typofix later to maint). + (merge 23c781f173 ps/update-ref-trans-hook-doc later to maint). + (merge 42efa1231a jk/filter-branch-sha256 later to maint). + (merge 4c8e3dca6e tb/push-simple-uses-branch-merge-config later to maint). + (merge 6534d436a2 bs/asciidoctor-installation-hints later to maint). + (merge 47957485b3 ab/read-tree later to maint). + (merge 2be927f3d1 ab/diff-no-index-tests later to maint). + (merge 76593c09bb ab/detox-gettext-tests later to maint). + (merge 28e29ee38b jc/doc-format-patch-clarify later to maint). + (merge fc12b6fdde fm/user-manual-use-preface later to maint). + (merge dba94e3a85 cc/test-helper-bloom-usage-fix later to maint). + (merge 61a7660516 hn/reftable-tables-doc-update later to maint). + (merge 81ed96a9b2 jt/fetch-pack-request-fix later to maint). + (merge 151b6c2dd7 jc/doc-do-not-capitalize-clarification later to maint). + (merge 9160068ac6 js/access-nul-emulation-on-windows later to maint). + (merge 7a14acdbe6 po/diff-patch-doc later to maint). + (merge f91371b948 pw/patience-diff-clean-up later to maint). + (merge 3a7f0908b6 mt/clean-clean later to maint). + (merge d4e2d15a8b ab/streaming-simplify later to maint). + (merge 0e59f7ad67 ah/merge-ort-i18n later to maint). + (merge e6f68f62e0 ls/typofix later to maint). diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches index 0452db2e67..55287d72e0 100644 --- a/Documentation/SubmittingPatches +++ b/Documentation/SubmittingPatches @@ -117,10 +117,13 @@ If in doubt which identifier to use, run `git log --no-merges` on the files you are modifying to see the current conventions. [[summary-section]] -It's customary to start the remainder of the first line after "area: " -with a lower-case letter. E.g. "doc: clarify...", not "doc: -Clarify...", or "githooks.txt: improve...", not "githooks.txt: -Improve...". +The title sentence after the "area:" prefix omits the full stop at the +end, and its first word is not capitalized unless there is a reason to +capitalize it other than because it is the first word in the sentence. +E.g. "doc: clarify...", not "doc: Clarify...", or "githooks.txt: +improve...", not "githooks.txt: Improve...". But "refs: HEAD is also +treated as a ref" is correct, as we spell `HEAD` in all caps even when +it appears in the middle of a sentence. [[meaningful-message]] The body should provide a meaningful commit message, which: diff --git a/Documentation/blame-options.txt b/Documentation/blame-options.txt index dc3bceb6d1..117f4cf806 100644 --- a/Documentation/blame-options.txt +++ b/Documentation/blame-options.txt @@ -1,6 +1,6 @@ -b:: Show blank SHA-1 for boundary commits. This can also - be controlled via the `blame.blankboundary` config option. + be controlled via the `blame.blankBoundary` config option. --root:: Do not treat root commits as boundaries. This can also be diff --git a/Documentation/config.txt b/Documentation/config.txt index 6ba50b1104..bf82766a6a 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -46,7 +46,7 @@ Subsection names are case sensitive and can contain any characters except newline and the null byte. Doublequote `"` and backslash can be included by escaping them as `\"` and `\\`, respectively. Backslashes preceding other characters are dropped when reading; for example, `\t` is read as -`t` and `\0` is read as `0` Section headers cannot span multiple lines. +`t` and `\0` is read as `0`. Section headers cannot span multiple lines. Variables may belong directly to a section or to a given subsection. You can have `[section]` if you have `[section "subsection"]`, but you don't need to. @@ -398,6 +398,8 @@ include::config/interactive.txt[] include::config/log.txt[] +include::config/lsrefs.txt[] + include::config/mailinfo.txt[] include::config/mailmap.txt[] diff --git a/Documentation/config/advice.txt b/Documentation/config/advice.txt index acbd0c09aa..8b2849ff7b 100644 --- a/Documentation/config/advice.txt +++ b/Documentation/config/advice.txt @@ -119,4 +119,8 @@ advice.*:: addEmptyPathspec:: Advice shown if a user runs the add command without providing the pathspec parameter. + updateSparsePath:: + Advice shown when either linkgit:git-add[1] or linkgit:git-rm[1] + is asked to update index entries outside the current sparse + checkout. -- diff --git a/Documentation/config/checkout.txt b/Documentation/config/checkout.txt index 2cddf7b4b4..bfbca90f0e 100644 --- a/Documentation/config/checkout.txt +++ b/Documentation/config/checkout.txt @@ -21,3 +21,24 @@ checkout.guess:: Provides the default value for the `--guess` or `--no-guess` option in `git checkout` and `git switch`. See linkgit:git-switch[1] and linkgit:git-checkout[1]. + +checkout.workers:: + The number of parallel workers to use when updating the working tree. + The default is one, i.e. sequential execution. If set to a value less + than one, Git will use as many workers as the number of logical cores + available. This setting and `checkout.thresholdForParallelism` affect + all commands that perform checkout. E.g. checkout, clone, reset, + sparse-checkout, etc. ++ +Note: parallel checkout usually delivers better performance for repositories +located on SSDs or over NFS. For repositories on spinning disks and/or machines +with a small number of cores, the default sequential checkout often performs +better. The size and compression level of a repository might also influence how +well the parallel version performs. + +checkout.thresholdForParallelism:: + When running parallel checkout with a small number of files, the cost + of subprocess spawning and inter-process communication might outweigh + the parallelization gains. This setting allows to define the minimum + number of files for which parallel checkout should be attempted. The + default is 100. diff --git a/Documentation/config/clone.txt b/Documentation/config/clone.txt index 47de36a5fe..7bcfbd18a5 100644 --- a/Documentation/config/clone.txt +++ b/Documentation/config/clone.txt @@ -2,3 +2,7 @@ clone.defaultRemoteName:: The name of the remote to create when cloning a repository. Defaults to `origin`, and can be overridden by passing the `--origin` command-line option to linkgit:git-clone[1]. + +clone.rejectShallow:: + Reject to clone a repository if it is a shallow one, can be overridden by + passing option `--reject-shallow` in command line. See linkgit:git-clone[1] diff --git a/Documentation/config/commitgraph.txt b/Documentation/config/commitgraph.txt index 4582c39fc4..30604e4a4c 100644 --- a/Documentation/config/commitgraph.txt +++ b/Documentation/config/commitgraph.txt @@ -1,3 +1,9 @@ +commitGraph.generationVersion:: + Specifies the type of generation number version to use when writing + or reading the commit-graph file. If version 1 is specified, then + the corrected commit dates will not be written or read. Defaults to + 2. + commitGraph.maxNewFilters:: Specifies the default value for the `--max-new-filters` option of `git commit-graph write` (c.f., linkgit:git-commit-graph[1]). diff --git a/Documentation/config/core.txt b/Documentation/config/core.txt index 160aacad84..c04f62a54a 100644 --- a/Documentation/config/core.txt +++ b/Documentation/config/core.txt @@ -625,4 +625,6 @@ core.abbrev:: computed based on the approximate number of packed objects in your repository, which hopefully is enough for abbreviated object names to stay unique for some time. + If set to "no", no abbreviation is made and the object names + are shown in their full length. The minimum length is 4. diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt index c3ae136eba..2d3331f55c 100644 --- a/Documentation/config/diff.txt +++ b/Documentation/config/diff.txt @@ -85,6 +85,8 @@ diff.ignoreSubmodules:: and 'git status' when `status.submoduleSummary` is set unless it is overridden by using the --ignore-submodules command-line option. The 'git submodule' commands are not affected by this setting. + By default this is set to untracked so that any untracked + submodules are ignored. diff.mnemonicPrefix:: If set, 'git diff' uses a prefix pair that is different from the diff --git a/Documentation/config/index.txt b/Documentation/config/index.txt index 7cb50b37e9..75f3a2d105 100644 --- a/Documentation/config/index.txt +++ b/Documentation/config/index.txt @@ -14,6 +14,11 @@ index.recordOffsetTable:: Defaults to 'true' if index.threads has been explicitly enabled, 'false' otherwise. +index.sparse:: + When enabled, write the index using sparse-directory entries. This + has no effect unless `core.sparseCheckout` and + `core.sparseCheckoutCone` are both enabled. Defaults to 'false'. + index.threads:: Specifies the number of threads to spawn when loading the index. This is meant to reduce index load time on multiprocessor machines. diff --git a/Documentation/config/init.txt b/Documentation/config/init.txt index dc77f8c844..79c79d6617 100644 --- a/Documentation/config/init.txt +++ b/Documentation/config/init.txt @@ -4,4 +4,4 @@ init.templateDir:: init.defaultBranch:: Allows overriding the default branch name e.g. when initializing - a new repository or when cloning an empty repository. + a new repository. diff --git a/Documentation/config/log.txt b/Documentation/config/log.txt index 208d5fdcaa..456eb07800 100644 --- a/Documentation/config/log.txt +++ b/Documentation/config/log.txt @@ -24,6 +24,11 @@ log.excludeDecoration:: the config option can be overridden by the `--decorate-refs` option. +log.diffMerges:: + Set default diff format to be used for merge commits. See + `--diff-merges` in linkgit:git-log[1] for details. + Defaults to `separate`. + log.follow:: If `true`, `git log` will act as if the `--follow` option was used when a single <path> is given. This has the same limitations as `--follow`, diff --git a/Documentation/config/lsrefs.txt b/Documentation/config/lsrefs.txt new file mode 100644 index 0000000000..adeda0f24d --- /dev/null +++ b/Documentation/config/lsrefs.txt @@ -0,0 +1,9 @@ +lsrefs.unborn:: + May be "advertise" (the default), "allow", or "ignore". If "advertise", + the server will respond to the client sending "unborn" (as described in + protocol-v2.txt) and will advertise support for this feature during the + protocol v2 capability advertisement. "allow" is the same as + "advertise" except that the server will not advertise support for this + feature; this is useful for load-balanced servers that cannot be + updated atomically (for example), since the administrator could + configure "allow", then after a delay, configure "advertise". diff --git a/Documentation/config/maintenance.txt b/Documentation/config/maintenance.txt index a5ead09e4b..18f0562131 100644 --- a/Documentation/config/maintenance.txt +++ b/Documentation/config/maintenance.txt @@ -15,8 +15,9 @@ maintenance.strategy:: * `none`: This default setting implies no task are run at any schedule. * `incremental`: This setting optimizes for performing small maintenance activities that do not delete any data. This does not schedule the `gc` - task, but runs the `prefetch` and `commit-graph` tasks hourly and the - `loose-objects` and `incremental-repack` tasks daily. + task, but runs the `prefetch` and `commit-graph` tasks hourly, the + `loose-objects` and `incremental-repack` tasks daily, and the `pack-refs` + task weekly. maintenance.<task>.enabled:: This boolean config option controls whether the maintenance task diff --git a/Documentation/config/mergetool.txt b/Documentation/config/mergetool.txt index 16a27443a3..cafbbef46a 100644 --- a/Documentation/config/mergetool.txt +++ b/Documentation/config/mergetool.txt @@ -13,6 +13,11 @@ mergetool.<tool>.cmd:: merged; 'MERGED' contains the name of the file to which the merge tool should write the results of a successful merge. +mergetool.<tool>.hideResolved:: + Allows the user to override the global `mergetool.hideResolved` value + for a specific tool. See `mergetool.hideResolved` for the full + description. + mergetool.<tool>.trustExitCode:: For a custom merge command, specify whether the exit code of the merge command can be used to determine whether the merge was @@ -40,6 +45,16 @@ mergetool.meld.useAutoMerge:: value of `false` avoids using `--auto-merge` altogether, and is the default value. +mergetool.hideResolved:: + During a merge Git will automatically resolve as many conflicts as + possible and write the 'MERGED' file containing conflict markers around + any conflicts that it cannot resolve; 'LOCAL' and 'REMOTE' normally + represent the versions of the file from before Git's conflict + resolution. This flag causes 'LOCAL' and 'REMOTE' to be overwriten so + that only the unresolved conflicts are presented to the merge tool. Can + be configured per-tool via the `mergetool.<tool>.hideResolved` + configuration variable. Defaults to `false`. + mergetool.keepBackup:: After performing a merge, the original file with conflict markers can be saved as a file with a `.orig` extension. If this variable diff --git a/Documentation/config/pack.txt b/Documentation/config/pack.txt index 837f1b1679..c0844d8d8e 100644 --- a/Documentation/config/pack.txt +++ b/Documentation/config/pack.txt @@ -122,6 +122,21 @@ pack.useSparse:: commits contain certain types of direct renames. Default is `true`. +pack.preferBitmapTips:: + When selecting which commits will receive bitmaps, prefer a + commit at the tip of any reference that is a suffix of any value + of this configuration over any other commits in the "selection + window". ++ +Note that setting this configuration to `refs/foo` does not mean that +the commits at the tips of `refs/foo/bar` and `refs/foo/baz` will +necessarily be selected. This is because commits are selected for +bitmaps from within a series of windows of variable length. ++ +If a commit at the tip of any reference which is a suffix of any value +of this configuration is seen in a window, it is immediately given +preference over any other commit in that window. + pack.writeBitmaps (deprecated):: This is a deprecated synonym for `repack.writeBitmaps`. @@ -133,3 +148,10 @@ pack.writeBitmapHashCache:: between an older, bitmapped pack and objects that have been pushed since the last gc). The downside is that it consumes 4 bytes per object of disk space. Defaults to true. + +pack.writeReverseIndex:: + When true, git will write a corresponding .rev file (see: + link:../technical/pack-format.html[Documentation/technical/pack-format.txt]) + for each new packfile that it writes in all places except for + linkgit:git-fast-import[1] and in the bulk checkin mechanism. + Defaults to false. diff --git a/Documentation/config/push.txt b/Documentation/config/push.txt index 21b256e0a4..f2667b2689 100644 --- a/Documentation/config/push.txt +++ b/Documentation/config/push.txt @@ -120,3 +120,10 @@ push.useForceIfIncludes:: `--force-if-includes` as an option to linkgit:git-push[1] in the command line. Adding `--no-force-if-includes` at the time of push overrides this configuration setting. + +push.negotiate:: + If set to "true", attempt to reduce the size of the packfile + sent by rounds of negotiation in which the client and the + server attempt to find commits in common. If "false", Git will + rely solely on the server's ref advertisement to find commits + in common. diff --git a/Documentation/config/rebase.txt b/Documentation/config/rebase.txt index 7f7a07d22f..8c979cb20f 100644 --- a/Documentation/config/rebase.txt +++ b/Documentation/config/rebase.txt @@ -1,10 +1,3 @@ -rebase.useBuiltin:: - Unused configuration variable. Used in Git versions 2.20 and - 2.21 as an escape hatch to enable the legacy shellscript - implementation of rebase. Now the built-in rewrite of it in C - is always used. Setting this will emit a warning, to alert any - remaining users that setting this now does nothing. - rebase.backend:: Default backend to use for rebasing. Possible choices are 'apply' or 'merge'. In the future, if the merge backend gains @@ -68,3 +61,6 @@ rebase.rescheduleFailedExec:: Automatically reschedule `exec` commands that failed. This only makes sense in interactive mode (or when an `--exec` option was provided). This is the same as specifying the `--reschedule-failed-exec` option. + +rebase.forkPoint:: + If set to false set `--no-fork-point` option by default. diff --git a/Documentation/config/stash.txt b/Documentation/config/stash.txt index 00eb35434e..413f907cba 100644 --- a/Documentation/config/stash.txt +++ b/Documentation/config/stash.txt @@ -5,6 +5,11 @@ stash.useBuiltin:: is always used. Setting this will emit a warning, to alert any remaining users that setting this now does nothing. +stash.showIncludeUntracked:: + If this is set to true, the `git stash show` command without an + option will show the untracked files of a stash entry. Defaults to + false. See description of 'show' command in linkgit:git-stash[1]. + stash.showPatch:: If this is set to true, the `git stash show` command without an option will show the stash entry in patch form. Defaults to false. diff --git a/Documentation/config/uploadpack.txt b/Documentation/config/uploadpack.txt index b0d761282c..32fad5bbe8 100644 --- a/Documentation/config/uploadpack.txt +++ b/Documentation/config/uploadpack.txt @@ -59,15 +59,16 @@ uploadpack.allowFilter:: uploadpackfilter.allow:: Provides a default value for unspecified object filters (see: the - below configuration variable). + below configuration variable). If set to `true`, this will also + enable all filters which get added in the future. Defaults to `true`. uploadpackfilter.<filter>.allow:: Explicitly allow or ban the object filter corresponding to `<filter>`, where `<filter>` may be one of: `blob:none`, - `blob:limit`, `tree`, `sparse:oid`, or `combine`. If using - combined filters, both `combine` and all of the nested filter - kinds must be allowed. Defaults to `uploadpackfilter.allow`. + `blob:limit`, `object:type`, `tree`, `sparse:oid`, or `combine`. + If using combined filters, both `combine` and all of the nested + filter kinds must be allowed. Defaults to `uploadpackfilter.allow`. uploadpackfilter.tree.maxDepth:: Only allow `--filter=tree:<n>` when `<n>` is no more than the value of diff --git a/Documentation/date-formats.txt b/Documentation/date-formats.txt index f1097fac69..99c455f51c 100644 --- a/Documentation/date-formats.txt +++ b/Documentation/date-formats.txt @@ -1,10 +1,7 @@ DATE FORMATS ------------ -The `GIT_AUTHOR_DATE`, `GIT_COMMITTER_DATE` environment variables -ifdef::git-commit[] -and the `--date` option -endif::git-commit[] +The `GIT_AUTHOR_DATE` and `GIT_COMMITTER_DATE` environment variables support the following date formats: Git internal format:: @@ -26,3 +23,9 @@ ISO 8601:: + NOTE: In addition, the date part is accepted in the following formats: `YYYY.MM.DD`, `MM/DD/YYYY` and `DD.MM.YYYY`. + +ifdef::git-commit[] +In addition to recognizing all date formats above, the `--date` option +will also try to make sense of other, more human-centric date formats, +such as relative dates like "yesterday" or "last Friday at noon". +endif::git-commit[] diff --git a/Documentation/diff-generate-patch.txt b/Documentation/diff-generate-patch.txt index b10ff4caa6..c78063d4f7 100644 --- a/Documentation/diff-generate-patch.txt +++ b/Documentation/diff-generate-patch.txt @@ -11,7 +11,7 @@ linkgit:git-diff-files[1] with the `-p` option produces patch text. You can customize the creation of patch text via the `GIT_EXTERNAL_DIFF` and the `GIT_DIFF_OPTS` environment variables -(see linkgit:git[1]). +(see linkgit:git[1]), and the `diff` attribute (see linkgit:gitattributes[5]). What the -p option produces is slightly different from the traditional diff format: @@ -74,6 +74,11 @@ separate lines indicate the old and the new mode. rename from b rename to a +5. Hunk headers mention the name of the function to which the hunk + applies. See "Defining a custom hunk-header" in + linkgit:gitattributes[5] for details of how to tailor to this to + specific languages. + Combined diff format -------------------- @@ -81,9 +86,9 @@ Combined diff format Any diff-generating command can take the `-c` or `--cc` option to produce a 'combined diff' when showing a merge. This is the default format when showing merges with linkgit:git-diff[1] or -linkgit:git-show[1]. Note also that you can give the `-m` option to any -of these commands to force generation of diffs with individual parents -of a merge. +linkgit:git-show[1]. Note also that you can give suitable +`--diff-merges` option to any of these commands to force generation of +diffs in specific format. A "combined diff" format looks like this: diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt index 746b144c76..530d115914 100644 --- a/Documentation/diff-options.txt +++ b/Documentation/diff-options.txt @@ -33,6 +33,64 @@ endif::git-diff[] show the patch by default, or to cancel the effect of `--patch`. endif::git-format-patch[] +ifdef::git-log[] +--diff-merges=(off|none|on|first-parent|1|separate|m|combined|c|dense-combined|cc):: +--no-diff-merges:: + Specify diff format to be used for merge commits. Default is + {diff-merges-default} unless `--first-parent` is in use, in which case + `first-parent` is the default. ++ +--diff-merges=(off|none)::: +--no-diff-merges::: + Disable output of diffs for merge commits. Useful to override + implied value. ++ +--diff-merges=on::: +--diff-merges=m::: +-m::: + This option makes diff output for merge commits to be shown in + the default format. `-m` will produce the output only if `-p` + is given as well. The default format could be changed using + `log.diffMerges` configuration parameter, which default value + is `separate`. ++ +--diff-merges=first-parent::: +--diff-merges=1::: + This option makes merge commits show the full diff with + respect to the first parent only. ++ +--diff-merges=separate::: + This makes merge commits show the full diff with respect to + each of the parents. Separate log entry and diff is generated + for each parent. ++ +--diff-merges=combined::: +--diff-merges=c::: +-c::: + With this option, diff output for a merge commit shows the + differences from each of the parents to the merge result + simultaneously instead of showing pairwise diff between a + parent and the result one at a time. Furthermore, it lists + only files which were modified from all parents. `-c` implies + `-p`. ++ +--diff-merges=dense-combined::: +--diff-merges=cc::: +--cc::: + With this option the output produced by + `--diff-merges=combined` is further compressed by omitting + uninteresting hunks whose contents in the parents have only + two variants and the merge result picks one of them without + modification. `--cc` implies `-p`. + +--combined-all-paths:: + This flag causes combined diffs (used for merge commits) to + list the name of the file from all parents. It thus only has + effect when `--diff-merges=[dense-]combined` is in use, and + is likely only useful if filename changes are detected (i.e. + when either rename or copy detection have been requested). +endif::git-log[] + -U<n>:: --unified=<n>:: Generate diffs with <n> lines of context instead of @@ -242,11 +300,14 @@ explained for the configuration variable `core.quotePath` (see linkgit:git-config[1]). --name-only:: - Show only names of changed files. + Show only names of changed files. The file names are often encoded in UTF-8. + For more information see the discussion about encoding in the linkgit:git-log[1] + manual page. --name-status:: Show only names and status of changed files. See the description of the `--diff-filter` option on what the status letters mean. + Just like `--name-only` the file names are often encoded in UTF-8. --submodule[=<format>]:: Specify how differences in submodules are shown. When specifying @@ -649,6 +710,14 @@ matches a pattern if removing any number of the final pathname components matches the pattern. For example, the pattern "`foo*bar`" matches "`fooasdfbar`" and "`foo/bar/baz/asdf`" but not "`foobarx`". +--skip-to=<file>:: +--rotate-to=<file>:: + Discard the files before the named <file> from the output + (i.e. 'skip to'), or move them to the end of the output + (i.e. 'rotate to'). These were invented primarily for use + of the `git difftool` command, and may not be very useful + otherwise. + ifndef::git-format-patch[] -R:: Swap two inputs; that is, show differences from index or diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt index 2bf77b46fd..9e7b4e189c 100644 --- a/Documentation/fetch-options.txt +++ b/Documentation/fetch-options.txt @@ -7,6 +7,10 @@ existing contents of `.git/FETCH_HEAD`. Without this option old data in `.git/FETCH_HEAD` will be overwritten. +--atomic:: + Use an atomic transaction to update local refs. Either all refs are + updated, or on error, no refs are updated. + --depth=<depth>:: Limit fetching to the specified number of commits from the tip of each remote branch history. If fetching to a 'shallow' repository @@ -106,6 +110,11 @@ ifndef::git-pull[] setting `fetch.writeCommitGraph`. endif::git-pull[] +--prefetch:: + Modify the configured refspec to place all refs into the + `refs/prefetch/` namespace. See the `prefetch` task in + linkgit:git-maintenance[1]. + -p:: --prune:: Before fetching, remove any remote-tracking references that no diff --git a/Documentation/git-am.txt b/Documentation/git-am.txt index 06bc063542..8714dfcb76 100644 --- a/Documentation/git-am.txt +++ b/Documentation/git-am.txt @@ -15,6 +15,7 @@ SYNOPSIS [--whitespace=<option>] [-C<n>] [-p<n>] [--directory=<dir>] [--exclude=<path>] [--include=<path>] [--reject] [-q | --quiet] [--[no-]scissors] [-S[<keyid>]] [--patch-format=<format>] + [--quoted-cr=<action>] [(<mbox> | <Maildir>)...] 'git am' (--continue | --skip | --abort | --quit | --show-current-patch[=(diff|raw)]) @@ -59,6 +60,9 @@ OPTIONS --no-scissors:: Ignore scissors lines (see linkgit:git-mailinfo[1]). +--quoted-cr=<action>:: + This flag will be passed down to 'git mailinfo' (see linkgit:git-mailinfo[1]). + -m:: --message-id:: Pass the `-m` flag to 'git mailinfo' (see linkgit:git-mailinfo[1]), @@ -79,7 +83,7 @@ OPTIONS Pass `-u` flag to 'git mailinfo' (see linkgit:git-mailinfo[1]). The proposed commit log message taken from the e-mail is re-coded into UTF-8 encoding (configuration variable - `i18n.commitencoding` can be used to specify project's + `i18n.commitEncoding` can be used to specify project's preferred encoding if it is not UTF-8). + This was optional in prior versions of git, but now it is the diff --git a/Documentation/git-apply.txt b/Documentation/git-apply.txt index 91d9a8601c..aa1ae56a25 100644 --- a/Documentation/git-apply.txt +++ b/Documentation/git-apply.txt @@ -84,12 +84,13 @@ OPTIONS -3:: --3way:: - When the patch does not apply cleanly, fall back on 3-way merge if - the patch records the identity of blobs it is supposed to apply to, - and we have those blobs available locally, possibly leaving the + Attempt 3-way merge if the patch records the identity of blobs it is supposed + to apply to and we have those blobs available locally, possibly leaving the conflict markers in the files in the working tree for the user to - resolve. This option implies the `--index` option, and is incompatible - with the `--reject` and the `--cached` options. + resolve. This option implies the `--index` option unless the + `--cached` option is used, and is incompatible with the `--reject` option. + When used with the `--cached` option, any conflicts are left at higher stages + in the cache. --build-fake-ancestor=<file>:: Newer 'git diff' output has embedded 'index information' diff --git a/Documentation/git-blame.txt b/Documentation/git-blame.txt index 34b496d485..3bf5d5d8b4 100644 --- a/Documentation/git-blame.txt +++ b/Documentation/git-blame.txt @@ -226,7 +226,7 @@ commit commentary), a blame viewer will not care. MAPPING AUTHORS --------------- -include::mailmap.txt[] +See linkgit:gitmailmap[5]. SEE ALSO diff --git a/Documentation/git-branch.txt b/Documentation/git-branch.txt index adaa1782a8..94dc9a54f2 100644 --- a/Documentation/git-branch.txt +++ b/Documentation/git-branch.txt @@ -78,8 +78,8 @@ renaming. If <newbranch> exists, -M must be used to force the rename to happen. The `-c` and `-C` options have the exact same semantics as `-m` and -`-M`, except instead of the branch being renamed it along with its -config and reflog will be copied to a new name. +`-M`, except instead of the branch being renamed, it will be copied to a +new name, along with its config and reflog. With a `-d` or `-D` option, `<branchname>` will be deleted. You may specify more than one branch for deletion. If the branch currently @@ -153,7 +153,7 @@ OPTIONS --column[=<options>]:: --no-column:: Display branch listing in columns. See configuration variable - column.branch for option syntax.`--column` and `--no-column` + `column.branch` for option syntax. `--column` and `--no-column` without options are equivalent to 'always' and 'never' respectively. + This option is only applicable in non-verbose mode. diff --git a/Documentation/git-cat-file.txt b/Documentation/git-cat-file.txt index 8e192d87db..4eb0421b3f 100644 --- a/Documentation/git-cat-file.txt +++ b/Documentation/git-cat-file.txt @@ -35,42 +35,42 @@ OPTIONS -t:: Instead of the content, show the object type identified by - <object>. + `<object>`. -s:: Instead of the content, show the object size identified by - <object>. + `<object>`. -e:: - Exit with zero status if <object> exists and is a valid - object. If <object> is of an invalid format exit with non-zero and + Exit with zero status if `<object>` exists and is a valid + object. If `<object>` is of an invalid format exit with non-zero and emits an error on stderr. -p:: - Pretty-print the contents of <object> based on its type. + Pretty-print the contents of `<object>` based on its type. <type>:: - Typically this matches the real type of <object> but asking + Typically this matches the real type of `<object>` but asking for a type that can trivially be dereferenced from the given - <object> is also permitted. An example is to ask for a - "tree" with <object> being a commit object that contains it, - or to ask for a "blob" with <object> being a tag object that + `<object>` is also permitted. An example is to ask for a + "tree" with `<object>` being a commit object that contains it, + or to ask for a "blob" with `<object>` being a tag object that points at it. --textconv:: Show the content as transformed by a textconv filter. In this case, - <object> has to be of the form <tree-ish>:<path>, or :<path> in + `<object>` has to be of the form `<tree-ish>:<path>`, or `:<path>` in order to apply the filter to the content recorded in the index at - <path>. + `<path>`. --filters:: Show the content as converted by the filters configured in - the current working tree for the given <path> (i.e. smudge filters, - end-of-line conversion, etc). In this case, <object> has to be of - the form <tree-ish>:<path>, or :<path>. + the current working tree for the given `<path>` (i.e. smudge filters, + end-of-line conversion, etc). In this case, `<object>` has to be of + the form `<tree-ish>:<path>`, or `:<path>`. --path=<path>:: - For use with --textconv or --filters, to allow specifying an object + For use with `--textconv` or `--filters`, to allow specifying an object name and a path separately, e.g. when it is difficult to figure out the revision from which the blob came. @@ -115,15 +115,15 @@ OPTIONS repository. --allow-unknown-type:: - Allow -s or -t to query broken/corrupt objects of unknown type. + Allow `-s` or `-t` to query broken/corrupt objects of unknown type. --follow-symlinks:: - With --batch or --batch-check, follow symlinks inside the + With `--batch` or `--batch-check`, follow symlinks inside the repository when requesting objects with extended SHA-1 expressions of the form tree-ish:path-in-tree. Instead of providing output about the link itself, provide output about the linked-to object. If a symlink points outside the - tree-ish (e.g. a link to /foo or a root-level link to ../foo), + tree-ish (e.g. a link to `/foo` or a root-level link to `../foo`), the portion of the link which is outside the tree will be printed. + @@ -175,15 +175,15 @@ respectively print: OUTPUT ------ -If `-t` is specified, one of the <type>. +If `-t` is specified, one of the `<type>`. -If `-s` is specified, the size of the <object> in bytes. +If `-s` is specified, the size of the `<object>` in bytes. -If `-e` is specified, no output, unless the <object> is malformed. +If `-e` is specified, no output, unless the `<object>` is malformed. -If `-p` is specified, the contents of <object> are pretty-printed. +If `-p` is specified, the contents of `<object>` are pretty-printed. -If <type> is specified, the raw (though uncompressed) contents of the <object> +If `<type>` is specified, the raw (though uncompressed) contents of the `<object>` will be returned. BATCH OUTPUT @@ -200,7 +200,7 @@ object, with placeholders of the form `%(atom)` expanded, followed by a newline. The available atoms are: `objectname`:: - The 40-hex object name of the object. + The full hex representation of the object name. `objecttype`:: The type of the object (the same as `cat-file -t` reports). @@ -215,8 +215,9 @@ newline. The available atoms are: `deltabase`:: If the object is stored as a delta on-disk, this expands to the - 40-hex sha1 of the delta base object. Otherwise, expands to the - null sha1 (40 zeroes). See `CAVEATS` below. + full hex representation of the delta base object name. + Otherwise, expands to the null OID (all zeroes). See `CAVEATS` + below. `rest`:: If this atom is used in the output string, input lines are split @@ -235,14 +236,14 @@ newline. For example, `--batch` without a custom format would produce: ------------ -<sha1> SP <type> SP <size> LF +<oid> SP <type> SP <size> LF <contents> LF ------------ Whereas `--batch-check='%(objectname) %(objecttype)'` would produce: ------------ -<sha1> SP <type> LF +<oid> SP <type> LF ------------ If a name is specified on stdin that cannot be resolved to an object in @@ -258,7 +259,7 @@ If a name is specified that might refer to more than one object (an ambiguous sh <object> SP ambiguous LF ------------ -If --follow-symlinks is used, and a symlink in the repository points +If `--follow-symlinks` is used, and a symlink in the repository points outside the repository, then `cat-file` will ignore any custom format and print: @@ -267,11 +268,11 @@ symlink SP <size> LF <symlink> LF ------------ -The symlink will either be absolute (beginning with a /), or relative -to the tree root. For instance, if dir/link points to ../../foo, then -<symlink> will be ../foo. <size> is the size of the symlink in bytes. +The symlink will either be absolute (beginning with a `/`), or relative +to the tree root. For instance, if dir/link points to `../../foo`, then +`<symlink>` will be `../foo`. `<size>` is the size of the symlink in bytes. -If --follow-symlinks is used, the following error messages will be +If `--follow-symlinks` is used, the following error messages will be displayed: ------------ diff --git a/Documentation/git-check-mailmap.txt b/Documentation/git-check-mailmap.txt index aa2055dbeb..02f4418323 100644 --- a/Documentation/git-check-mailmap.txt +++ b/Documentation/git-check-mailmap.txt @@ -36,10 +36,17 @@ name is provided or known to the 'mailmap', ``Name $$<user@host>$$'' is printed; otherwise only ``$$<user@host>$$'' is printed. +CONFIGURATION +------------- + +See `mailmap.file` and `mailmap.blob` in linkgit:git-config[1] for how +to specify a custom `.mailmap` target file or object. + + MAPPING AUTHORS --------------- -include::mailmap.txt[] +See linkgit:gitmailmap[5]. GIT diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt index 02d9c19cec..3fe3810f1c 100644 --- a/Documentation/git-clone.txt +++ b/Documentation/git-clone.txt @@ -15,7 +15,7 @@ SYNOPSIS [--dissociate] [--separate-git-dir <git dir>] [--depth <depth>] [--[no-]single-branch] [--no-tags] [--recurse-submodules[=<pathspec>]] [--[no-]shallow-submodules] - [--[no-]remote-submodules] [--jobs <n>] [--sparse] + [--[no-]remote-submodules] [--jobs <n>] [--sparse] [--[no-]reject-shallow] [--filter=<filter>] [--] <repository> [<directory>] @@ -149,6 +149,11 @@ objects from the source repository into a pack in the cloned repository. --no-checkout:: No checkout of HEAD is performed after the clone is complete. +--[no-]reject-shallow:: + Fail if the source repository is a shallow repository. + The 'clone.rejectShallow' configuration variable can be used to + specify the default. + --bare:: Make a 'bare' Git repository. That is, instead of creating `<directory>` and placing the administrative diff --git a/Documentation/git-commit.txt b/Documentation/git-commit.txt index 17150fa7ea..340c5fbb48 100644 --- a/Documentation/git-commit.txt +++ b/Documentation/git-commit.txt @@ -9,12 +9,13 @@ SYNOPSIS -------- [verse] 'git commit' [-a | --interactive | --patch] [-s] [-v] [-u<mode>] [--amend] - [--dry-run] [(-c | -C | --fixup | --squash) <commit>] + [--dry-run] [(-c | -C | --squash) <commit> | --fixup [(amend|reword):]<commit>)] [-F <file> | -m <msg>] [--reset-author] [--allow-empty] [--allow-empty-message] [--no-verify] [-e] [--author=<author>] [--date=<date>] [--cleanup=<mode>] [--[no-]status] [-i | -o] [--pathspec-from-file=<file> [--pathspec-file-nul]] - [-S[<keyid>]] [--] [<pathspec>...] + [(--trailer <token>[(=|:)<value>])...] [-S[<keyid>]] + [--] [<pathspec>...] DESCRIPTION ----------- @@ -86,11 +87,44 @@ OPTIONS Like '-C', but with `-c` the editor is invoked, so that the user can further edit the commit message. ---fixup=<commit>:: - Construct a commit message for use with `rebase --autosquash`. - The commit message will be the subject line from the specified - commit with a prefix of "fixup! ". See linkgit:git-rebase[1] - for details. +--fixup=[(amend|reword):]<commit>:: + Create a new commit which "fixes up" `<commit>` when applied with + `git rebase --autosquash`. Plain `--fixup=<commit>` creates a + "fixup!" commit which changes the content of `<commit>` but leaves + its log message untouched. `--fixup=amend:<commit>` is similar but + creates an "amend!" commit which also replaces the log message of + `<commit>` with the log message of the "amend!" commit. + `--fixup=reword:<commit>` creates an "amend!" commit which + replaces the log message of `<commit>` with its own log message + but makes no changes to the content of `<commit>`. ++ +The commit created by plain `--fixup=<commit>` has a subject +composed of "fixup!" followed by the subject line from <commit>, +and is recognized specially by `git rebase --autosquash`. The `-m` +option may be used to supplement the log message of the created +commit, but the additional commentary will be thrown away once the +"fixup!" commit is squashed into `<commit>` by +`git rebase --autosquash`. ++ +The commit created by `--fixup=amend:<commit>` is similar but its +subject is instead prefixed with "amend!". The log message of +<commit> is copied into the log message of the "amend!" commit and +opened in an editor so it can be refined. When `git rebase +--autosquash` squashes the "amend!" commit into `<commit>`, the +log message of `<commit>` is replaced by the refined log message +from the "amend!" commit. It is an error for the "amend!" commit's +log message to be empty unless `--allow-empty-message` is +specified. ++ +`--fixup=reword:<commit>` is shorthand for `--fixup=amend:<commit> +--only`. It creates an "amend!" commit with only a log message +(ignoring any changes staged in the index). When squashed by `git +rebase --autosquash`, it replaces the log message of `<commit>` +without making any other changes. ++ +Neither "fixup!" nor "amend!" commits change authorship of +`<commit>` when applied by `git rebase --autosquash`. +See linkgit:git-rebase[1] for details. --squash=<commit>:: Construct a commit message for use with `rebase --autosquash`. @@ -166,6 +200,17 @@ The `-m` option is mutually exclusive with `-c`, `-C`, and `-F`. include::signoff-option.txt[] +--trailer <token>[(=|:)<value>]:: + Specify a (<token>, <value>) pair that should be applied as a + trailer. (e.g. `git commit --trailer "Signed-off-by:C O Mitter \ + <committer@example.com>" --trailer "Helped-by:C O Mitter \ + <committer@example.com>"` will add the "Signed-off-by" trailer + and the "Helped-by" trailer to the commit message.) + The `trailer.*` configuration variables + (linkgit:git-interpret-trailers[1]) can be used to define if + a duplicated trailer is omitted, where in the run of trailers + each trailer would appear, and other details. + -n:: --no-verify:: This option bypasses the pre-commit and commit-msg hooks. diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt index 0e9351d3cb..5cddadafd2 100644 --- a/Documentation/git-config.txt +++ b/Documentation/git-config.txt @@ -340,12 +340,33 @@ GIT_CONFIG:: Using the "--global" option forces this to ~/.gitconfig. Using the "--system" option forces this to $(prefix)/etc/gitconfig. +GIT_CONFIG_GLOBAL:: +GIT_CONFIG_SYSTEM:: + Take the configuration from the given files instead from global or + system-level configuration. See linkgit:git[1] for details. + GIT_CONFIG_NOSYSTEM:: Whether to skip reading settings from the system-wide $(prefix)/etc/gitconfig file. See linkgit:git[1] for details. See also <<FILES>>. +GIT_CONFIG_COUNT:: +GIT_CONFIG_KEY_<n>:: +GIT_CONFIG_VALUE_<n>:: + If GIT_CONFIG_COUNT is set to a positive number, all environment pairs + GIT_CONFIG_KEY_<n> and GIT_CONFIG_VALUE_<n> up to that number will be + added to the process's runtime configuration. The config pairs are + zero-indexed. Any missing key or value is treated as an error. An empty + GIT_CONFIG_COUNT is treated the same as GIT_CONFIG_COUNT=0, namely no + pairs are processed. These environment variables will override values + in configuration files, but will be overridden by any explicit options + passed via `git -c`. ++ +This is useful for cases where you want to spawn multiple git commands +with a common configuration but cannot depend on a configuration file, +for example when writing scripts. + [[EXAMPLES]] EXAMPLES diff --git a/Documentation/git-credential.txt b/Documentation/git-credential.txt index 31c81c4c02..206e3c5f40 100644 --- a/Documentation/git-credential.txt +++ b/Documentation/git-credential.txt @@ -159,3 +159,7 @@ empty string. + Components which are missing from the URL (e.g., there is no username in the example above) will be left unset. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt index 1b1c71ad9d..f2e4a47ebe 100644 --- a/Documentation/git-cvsserver.txt +++ b/Documentation/git-cvsserver.txt @@ -24,6 +24,18 @@ Usage: [verse] 'git-cvsserver' [<options>] [pserver|server] [<directory> ...] +DESCRIPTION +----------- + +This application is a CVS emulation layer for Git. + +It is highly functional. However, not all methods are implemented, +and for those methods that are implemented, +not all switches are implemented. + +Testing has been done using both the CLI CVS client, and the Eclipse CVS +plugin. Most functionality works fine with both of these clients. + OPTIONS ------- @@ -57,18 +69,6 @@ access still needs to be enabled by the `gitcvs.enabled` config option unless `--export-all` was given, too. -DESCRIPTION ------------ - -This application is a CVS emulation layer for Git. - -It is highly functional. However, not all methods are implemented, -and for those methods that are implemented, -not all switches are implemented. - -Testing has been done using both the CLI CVS client, and the Eclipse CVS -plugin. Most functionality works fine with both of these clients. - LIMITATIONS ----------- diff --git a/Documentation/git-difftool.txt b/Documentation/git-difftool.txt index 484c485fd0..143b0c49d7 100644 --- a/Documentation/git-difftool.txt +++ b/Documentation/git-difftool.txt @@ -34,6 +34,14 @@ OPTIONS This is the default behaviour; the option is provided to override any configuration settings. +--rotate-to=<file>:: + Start showing the diff for the given path, + the paths before it will move to end and output. + +--skip-to=<file>:: + Start showing the diff for the given path, skipping all + the paths before it. + -t <tool>:: --tool=<tool>:: Use the diff tool specified by <tool>. Valid values include diff --git a/Documentation/git-for-each-ref.txt b/Documentation/git-for-each-ref.txt index 2962f85a50..2ae2478de7 100644 --- a/Documentation/git-for-each-ref.txt +++ b/Documentation/git-for-each-ref.txt @@ -260,11 +260,9 @@ contents:lines=N:: The first `N` lines of the message. Additionally, the trailers as interpreted by linkgit:git-interpret-trailers[1] -are obtained as `trailers` (or by using the historical alias -`contents:trailers`). Non-trailer lines from the trailer block can be omitted -with `trailers:only`. Whitespace-continuations can be removed from trailers so -that each trailer appears on a line by itself with its full content with -`trailers:unfold`. Both can be used together as `trailers:unfold,only`. +are obtained as `trailers[:options]` (or by using the historical alias +`contents:trailers[:options]`). For valid [:option] values see `trailers` +section of linkgit:git-log[1]. For sorting purposes, fields with numeric values sort in numeric order (`objectsize`, `authordate`, `committerdate`, `creatordate`, `taggerdate`). diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt index 3e49bf2210..fe2f69d36e 100644 --- a/Documentation/git-format-patch.txt +++ b/Documentation/git-format-patch.txt @@ -36,11 +36,28 @@ SYNOPSIS DESCRIPTION ----------- -Prepare each commit with its patch in -one file per commit, formatted to resemble UNIX mailbox format. +Prepare each non-merge commit with its "patch" in +one "message" per commit, formatted to resemble a UNIX mailbox. The output of this command is convenient for e-mail submission or for use with 'git am'. +A "message" generated by the command consists of three parts: + +* A brief metadata header that begins with `From <commit>` + with a fixed `Mon Sep 17 00:00:00 2001` datestamp to help programs + like "file(1)" to recognize that the file is an output from this + command, fields that record the author identity, the author date, + and the title of the change (taken from the first paragraph of the + commit log message). + +* The second and subsequent paragraphs of the commit log message. + +* The "patch", which is the "diff -p --stat" output (see + linkgit:git-diff[1]) between the commit and its parent. + +The log message and the patch is separated by a line with a +three-dash line. + There are two ways to specify which commits to operate on. 1. A single commit, <since>, specifies that the commits leading @@ -221,6 +238,11 @@ populated with placeholder text. `--subject-prefix` option) has ` v<n>` appended to it. E.g. `--reroll-count=4` may produce `v4-0001-add-makefile.patch` file that has "Subject: [PATCH v4 1/20] Add makefile" in it. + `<n>` does not have to be an integer (e.g. "--reroll-count=4.4", + or "--reroll-count=4rev2" are allowed), but the downside of + using such a reroll-count is that the range-diff/interdiff + with the previous version does not state exactly which + version the new interation is compared against. --to=<email>:: Add a `To:` header to the email headers. This is in addition @@ -718,6 +740,14 @@ use it only when you know the recipient uses Git to apply your patch. $ git format-patch -3 ------------ +CAVEATS +------- + +Note that `format-patch` will omit merge commits from the output, even +if they are part of the requested range. A simple "patch" does not +include enough information for the receiving end to reproduce the same +merge commit. + SEE ALSO -------- linkgit:git-am[1], linkgit:git-send-email[1] diff --git a/Documentation/git-gc.txt b/Documentation/git-gc.txt index 0c114ad1ca..853967dea0 100644 --- a/Documentation/git-gc.txt +++ b/Documentation/git-gc.txt @@ -117,12 +117,14 @@ NOTES 'git gc' tries very hard not to delete objects that are referenced anywhere in your repository. In particular, it will keep not only objects referenced by your current set of branches and tags, but also -objects referenced by the index, remote-tracking branches, notes saved -by 'git notes' under refs/notes/, reflogs (which may reference commits -in branches that were later amended or rewound), and anything else in -the refs/* namespace. If you are expecting some objects to be deleted -and they aren't, check all of those locations and decide whether it -makes sense in your case to remove those references. +objects referenced by the index, remote-tracking branches, reflogs +(which may reference commits in branches that were later amended or +rewound), and anything else in the refs/* namespace. Note that a note +(of the kind created by 'git notes') attached to an object does not +contribute in keeping the object alive. If you are expecting some +objects to be deleted and they aren't, check all of those locations +and decide whether it makes sense in your case to remove those +references. On the other hand, when 'git gc' runs concurrently with another process, there is a risk of it deleting an object that the other process is using diff --git a/Documentation/git-grep.txt b/Documentation/git-grep.txt index 4e0ba8234a..3d393fbac1 100644 --- a/Documentation/git-grep.txt +++ b/Documentation/git-grep.txt @@ -38,38 +38,6 @@ are lists of one or more search expressions separated by newline characters. An empty string as search expression matches all lines. -CONFIGURATION -------------- - -grep.lineNumber:: - If set to true, enable `-n` option by default. - -grep.column:: - If set to true, enable the `--column` option by default. - -grep.patternType:: - Set the default matching behavior. Using a value of 'basic', 'extended', - 'fixed', or 'perl' will enable the `--basic-regexp`, `--extended-regexp`, - `--fixed-strings`, or `--perl-regexp` option accordingly, while the - value 'default' will return to the default matching behavior. - -grep.extendedRegexp:: - If set to true, enable `--extended-regexp` option by default. This - option is ignored when the `grep.patternType` option is set to a value - other than 'default'. - -grep.threads:: - Number of grep worker threads to use. If unset (or set to 0), Git will - use as many threads as the number of logical cores available. - -grep.fullName:: - If set to true, enable `--full-name` option by default. - -grep.fallbackToNoIndex:: - If set to true, fall back to git grep --no-index if git grep - is executed outside of a git repository. Defaults to false. - - OPTIONS ------- --cached:: @@ -363,6 +331,38 @@ with multiple threads might perform slower than single threaded if `--textconv` is given and there're too many text conversions. So if you experience low performance in this case, it might be desirable to use `--threads=1`. +CONFIGURATION +------------- + +grep.lineNumber:: + If set to true, enable `-n` option by default. + +grep.column:: + If set to true, enable the `--column` option by default. + +grep.patternType:: + Set the default matching behavior. Using a value of 'basic', 'extended', + 'fixed', or 'perl' will enable the `--basic-regexp`, `--extended-regexp`, + `--fixed-strings`, or `--perl-regexp` option accordingly, while the + value 'default' will return to the default matching behavior. + +grep.extendedRegexp:: + If set to true, enable `--extended-regexp` option by default. This + option is ignored when the `grep.patternType` option is set to a value + other than 'default'. + +grep.threads:: + Number of grep worker threads to use. If unset (or set to 0), Git will + use as many threads as the number of logical cores available. + +grep.fullName:: + If set to true, enable `--full-name` option by default. + +grep.fallbackToNoIndex:: + If set to true, fall back to git grep --no-index if git grep + is executed outside of a git repository. Defaults to false. + + GIT --- Part of the linkgit:git[1] suite diff --git a/Documentation/git-http-fetch.txt b/Documentation/git-http-fetch.txt index 4deb4893f5..9fa17b60e4 100644 --- a/Documentation/git-http-fetch.txt +++ b/Documentation/git-http-fetch.txt @@ -41,11 +41,17 @@ commit-id:: <commit-id>['\t'<filename-as-in--w>] --packfile=<hash>:: - Instead of a commit id on the command line (which is not expected in + For internal use only. Instead of a commit id on the command + line (which is not expected in this case), 'git http-fetch' fetches the packfile directly at the given URL and uses index-pack to generate corresponding .idx and .keep files. The hash is used to determine the name of the temporary file and is - arbitrary. The output of index-pack is printed to stdout. + arbitrary. The output of index-pack is printed to stdout. Requires + --index-pack-args. + +--index-pack-args=<args>:: + For internal use only. The command to run on the contents of the + downloaded pack. Arguments are URL-encoded separated by spaces. --recover:: Verify that everything reachable from target is fetched. Used after diff --git a/Documentation/git-index-pack.txt b/Documentation/git-index-pack.txt index af0c26232c..7fa74b9e79 100644 --- a/Documentation/git-index-pack.txt +++ b/Documentation/git-index-pack.txt @@ -9,17 +9,18 @@ git-index-pack - Build pack index file for an existing packed archive SYNOPSIS -------- [verse] -'git index-pack' [-v] [-o <index-file>] <pack-file> +'git index-pack' [-v] [-o <index-file>] [--[no-]rev-index] <pack-file> 'git index-pack' --stdin [--fix-thin] [--keep] [-v] [-o <index-file>] - [<pack-file>] + [--[no-]rev-index] [<pack-file>] DESCRIPTION ----------- Reads a packed archive (.pack) from the specified file, and -builds a pack index file (.idx) for it. The packed archive -together with the pack index can then be placed in the -objects/pack/ directory of a Git repository. +builds a pack index file (.idx) for it. Optionally writes a +reverse-index (.rev) for the specified pack. The packed +archive together with the pack index can then be placed in +the objects/pack/ directory of a Git repository. OPTIONS @@ -35,6 +36,13 @@ OPTIONS fails if the name of packed archive does not end with .pack). +--[no-]rev-index:: + When this flag is provided, generate a reverse index + (a `.rev` file) corresponding to the given pack. If + `--verify` is given, ensure that the existing + reverse index is correct. Takes precedence over + `pack.writeReverseIndex`. + --stdin:: When this flag is provided, the pack is read from stdin instead and a copy is then written to <pack-file>. If @@ -78,7 +86,12 @@ OPTIONS Die if the pack contains broken links. For internal use only. --fsck-objects:: - Die if the pack contains broken objects. For internal use only. + For internal use only. ++ +Die if the pack contains broken objects. If the pack contains a tree +pointing to a .gitmodules blob that does not exist, prints the hash of +that blob (for the caller to check) after the hash that goes into the +name of the pack/idx file (see "Notes"). --threads=<n>:: Specifies the number of threads to spawn when resolving diff --git a/Documentation/git-interpret-trailers.txt b/Documentation/git-interpret-trailers.txt index 96ec6499f0..956a01d184 100644 --- a/Documentation/git-interpret-trailers.txt +++ b/Documentation/git-interpret-trailers.txt @@ -232,25 +232,38 @@ trailer.<token>.ifmissing:: that option for trailers with the specified <token>. trailer.<token>.command:: - This option can be used to specify a shell command that will - be called to automatically add or modify a trailer with the - specified <token>. + This option behaves in the same way as 'trailer.<token>.cmd', except + that it doesn't pass anything as argument to the specified command. + Instead the first occurrence of substring $ARG is replaced by the + value that would be passed as argument. + -When this option is specified, the behavior is as if a special -'<token>=<value>' argument were added at the beginning of the command -line, where <value> is taken to be the standard output of the -specified command with any leading and trailing whitespace trimmed -off. +The 'trailer.<token>.command' option has been deprecated in favor of +'trailer.<token>.cmd' due to the fact that $ARG in the user's command is +only replaced once and that the original way of replacing $ARG is not safe. + -If the command contains the `$ARG` string, this string will be -replaced with the <value> part of an existing trailer with the same -<token>, if any, before the command is launched. +When both 'trailer.<token>.cmd' and 'trailer.<token>.command' are given +for the same <token>, 'trailer.<token>.cmd' is used and +'trailer.<token>.command' is ignored. + +trailer.<token>.cmd:: + This option can be used to specify a shell command that will be called: + once to automatically add a trailer with the specified <token>, and then + each time a '--trailer <token>=<value>' argument to modify the <value> of + the trailer that this option would produce. + -If some '<token>=<value>' arguments are also passed on the command -line, when a 'trailer.<token>.command' is configured, the command will -also be executed for each of these arguments. And the <value> part of -these arguments, if any, will be used to replace the `$ARG` string in -the command. +When the specified command is first called to add a trailer +with the specified <token>, the behavior is as if a special +'--trailer <token>=<value>' argument was added at the beginning +of the "git interpret-trailers" command, where <value> +is taken to be the standard output of the command with any +leading and trailing whitespace trimmed off. ++ +If some '--trailer <token>=<value>' arguments are also passed +on the command line, the command is called again once for each +of these arguments with the same <token>. And the <value> part +of these arguments, if any, will be passed to the command as its +first argument. This way the command can produce a <value> computed +from the <value> passed in the '--trailer <token>=<value>' argument. EXAMPLES -------- @@ -333,6 +346,55 @@ subject Fix #42 ------------ +* Configure a 'help' trailer with a cmd use a script `glog-find-author` + which search specified author identity from git log in git repository + and show how it works: ++ +------------ +$ cat ~/bin/glog-find-author +#!/bin/sh +test -n "$1" && git log --author="$1" --pretty="%an <%ae>" -1 || true +$ git config trailer.help.key "Helped-by: " +$ git config trailer.help.ifExists "addIfDifferentNeighbor" +$ git config trailer.help.cmd "~/bin/glog-find-author" +$ git interpret-trailers --trailer="help:Junio" --trailer="help:Couder" <<EOF +> subject +> +> message +> +> EOF +subject + +message + +Helped-by: Junio C Hamano <gitster@pobox.com> +Helped-by: Christian Couder <christian.couder@gmail.com> +------------ + +* Configure a 'ref' trailer with a cmd use a script `glog-grep` + to grep last relevant commit from git log in the git repository + and show how it works: ++ +------------ +$ cat ~/bin/glog-grep +#!/bin/sh +test -n "$1" && git log --grep "$1" --pretty=reference -1 || true +$ git config trailer.ref.key "Reference-to: " +$ git config trailer.ref.ifExists "replace" +$ git config trailer.ref.cmd "~/bin/glog-grep" +$ git interpret-trailers --trailer="ref:Add copyright notices." <<EOF +> subject +> +> message +> +> EOF +subject + +message + +Reference-to: 8bc9a0c769 (Add copyright notices., 2005-04-07) +------------ + * Configure a 'see' trailer with a command to show the subject of a commit that is related, and show how it works: + diff --git a/Documentation/git-log.txt b/Documentation/git-log.txt index dd189a353a..1bbf865a1b 100644 --- a/Documentation/git-log.txt +++ b/Documentation/git-log.txt @@ -107,47 +107,15 @@ DIFF FORMATTING By default, `git log` does not generate any diff output. The options below can be used to show the changes made by each commit. -Note that unless one of `-c`, `--cc`, or `-m` is given, merge commits -will never show a diff, even if a diff format like `--patch` is -selected, nor will they match search options like `-S`. The exception is -when `--first-parent` is in use, in which merges are treated like normal -single-parent commits (this can be overridden by providing a -combined-diff option or with `--no-diff-merges`). - --c:: - With this option, diff output for a merge commit - shows the differences from each of the parents to the merge result - simultaneously instead of showing pairwise diff between a parent - and the result one at a time. Furthermore, it lists only files - which were modified from all parents. - ---cc:: - This flag implies the `-c` option and further compresses the - patch output by omitting uninteresting hunks whose contents in - the parents have only two variants and the merge result picks - one of them without modification. - ---combined-all-paths:: - This flag causes combined diffs (used for merge commits) to - list the name of the file from all parents. It thus only has - effect when -c or --cc are specified, and is likely only - useful if filename changes are detected (i.e. when either - rename or copy detection have been requested). - --m:: - This flag makes the merge commits show the full diff like - regular commits; for each merge parent, a separate log entry - and diff is generated. An exception is that only diff against - the first parent is shown when `--first-parent` option is given; - in that case, the output represents the changes the merge - brought _into_ the then-current branch. - ---diff-merges=off:: ---no-diff-merges:: - Disable output of diffs for merge commits (default). Useful to - override `-m`, `-c`, or `--cc`. +Note that unless one of `--diff-merges` variants (including short +`-m`, `-c`, and `--cc` options) is explicitly given, merge commits +will not show a diff, even if a diff format like `--patch` is +selected, nor will they match search options like `-S`. The exception +is when `--first-parent` is in use, in which case `first-parent` is +the default format. :git-log: 1 +:diff-merges-default: `off` include::diff-options.txt[] include::diff-generate-patch.txt[] diff --git a/Documentation/git-ls-files.txt b/Documentation/git-ls-files.txt index 0a3b5265b3..6d11ab506b 100644 --- a/Documentation/git-ls-files.txt +++ b/Documentation/git-ls-files.txt @@ -13,6 +13,7 @@ SYNOPSIS (--[cached|deleted|others|ignored|stage|unmerged|killed|modified])* (-[c|d|o|i|s|u|k|m])* [--eol] + [--deduplicate] [-x <pattern>|--exclude=<pattern>] [-X <file>|--exclude-from=<file>] [--exclude-per-directory=<file>] @@ -80,6 +81,13 @@ OPTIONS \0 line termination on output and do not quote filenames. See OUTPUT below for more information. +--deduplicate:: + When only filenames are shown, suppress duplicates that may + come from having multiple stages during a merge, or giving + `--deleted` and `--modified` option at the same time. + When any of the `-t`, `--unmerged`, or `--stage` option is + in use, this option has no effect. + -x <pattern>:: --exclude=<pattern>:: Skip untracked files matching pattern. diff --git a/Documentation/git-mailinfo.txt b/Documentation/git-mailinfo.txt index 7a6aed0e30..3fcfd965fd 100644 --- a/Documentation/git-mailinfo.txt +++ b/Documentation/git-mailinfo.txt @@ -9,7 +9,9 @@ git-mailinfo - Extracts patch and authorship from a single e-mail message SYNOPSIS -------- [verse] -'git mailinfo' [-k|-b] [-u | --encoding=<encoding> | -n] [--[no-]scissors] <msg> <patch> +'git mailinfo' [-k|-b] [-u | --encoding=<encoding> | -n] + [--[no-]scissors] [--quoted-cr=<action>] + <msg> <patch> DESCRIPTION @@ -53,7 +55,7 @@ character. The commit log message, author name and author email are taken from the e-mail, and after minimally decoding MIME transfer encoding, re-coded in the charset specified by - i18n.commitencoding (defaulting to UTF-8) by transliterating + `i18n.commitEncoding` (defaulting to UTF-8) by transliterating them. This used to be optional but now it is the default. + Note that the patch is always used as-is without charset @@ -61,7 +63,7 @@ conversion, even with this flag. --encoding=<encoding>:: Similar to -u. But when re-coding, the charset specified here is - used instead of the one specified by i18n.commitencoding or UTF-8. + used instead of the one specified by `i18n.commitEncoding` or UTF-8. -n:: Disable all charset re-coding of the metadata. @@ -89,6 +91,23 @@ This can be enabled by default with the configuration option mailinfo.scissors. --no-scissors:: Ignore scissors lines. Useful for overriding mailinfo.scissors settings. +--quoted-cr=<action>:: + Action when processes email messages sent with base64 or + quoted-printable encoding, and the decoded lines end with a CRLF + instead of a simple LF. ++ +The valid actions are: ++ +-- +* `nowarn`: Git will do nothing when such a CRLF is found. +* `warn`: Git will issue a warning for each message if such a CRLF is + found. +* `strip`: Git will convert those CRLF to LF. +-- ++ +The default action could be set by configuration option `mailinfo.quotedCR`. +If no such configuration option has been set, `warn` will be used. + <msg>:: The commit log message extracted from e-mail, usually except the title line which comes from e-mail Subject. diff --git a/Documentation/git-maintenance.txt b/Documentation/git-maintenance.txt index 6fe1e5e105..1e738ad398 100644 --- a/Documentation/git-maintenance.txt +++ b/Documentation/git-maintenance.txt @@ -92,10 +92,8 @@ commit-graph:: prefetch:: The `prefetch` task updates the object directory with the latest objects from all registered remotes. For each remote, a `git fetch` - command is run. The refmap is custom to avoid updating local or remote - branches (those in `refs/heads` or `refs/remotes`). Instead, the - remote refs are stored in `refs/prefetch/<remote>/`. Also, tags are - not updated. + command is run. The configured refspec is modified to place all + requested refs within `refs/prefetch/`. Also, tags are not updated. + This is done to avoid disrupting the remote-tracking branches. The end users expect these refs to stay unmoved unless they initiate a fetch. With prefetch @@ -145,6 +143,12 @@ incremental-repack:: which is a special case that attempts to repack all pack-files into a single pack-file. +pack-refs:: + The `pack-refs` task collects the loose reference files and + collects them into a single file. This speeds up operations that + need to iterate across many references. See linkgit:git-pack-refs[1] + for more information. + OPTIONS ------- --auto:: @@ -218,6 +222,122 @@ Further, the `git gc` command should not be combined with but does not take the lock in the same way as `git maintenance run`. If possible, use `git maintenance run --task=gc` instead of `git gc`. +The following sections describe the mechanisms put in place to run +background maintenance by `git maintenance start` and how to customize +them. + +BACKGROUND MAINTENANCE ON POSIX SYSTEMS +--------------------------------------- + +The standard mechanism for scheduling background tasks on POSIX systems +is cron(8). This tool executes commands based on a given schedule. The +current list of user-scheduled tasks can be found by running `crontab -l`. +The schedule written by `git maintenance start` is similar to this: + +----------------------------------------------------------------------- +# BEGIN GIT MAINTENANCE SCHEDULE +# The following schedule was created by Git +# Any edits made in this region might be +# replaced in the future by a Git command. + +0 1-23 * * * "/<path>/git" --exec-path="/<path>" for-each-repo --config=maintenance.repo maintenance run --schedule=hourly +0 0 * * 1-6 "/<path>/git" --exec-path="/<path>" for-each-repo --config=maintenance.repo maintenance run --schedule=daily +0 0 * * 0 "/<path>/git" --exec-path="/<path>" for-each-repo --config=maintenance.repo maintenance run --schedule=weekly + +# END GIT MAINTENANCE SCHEDULE +----------------------------------------------------------------------- + +The comments are used as a region to mark the schedule as written by Git. +Any modifications within this region will be completely deleted by +`git maintenance stop` or overwritten by `git maintenance start`. + +The `crontab` entry specifies the full path of the `git` executable to +ensure that the executed `git` command is the same one with which +`git maintenance start` was issued independent of `PATH`. If the same user +runs `git maintenance start` with multiple Git executables, then only the +latest executable is used. + +These commands use `git for-each-repo --config=maintenance.repo` to run +`git maintenance run --schedule=<frequency>` on each repository listed in +the multi-valued `maintenance.repo` config option. These are typically +loaded from the user-specific global config. The `git maintenance` process +then determines which maintenance tasks are configured to run on each +repository with each `<frequency>` using the `maintenance.<task>.schedule` +config options. These values are loaded from the global or repository +config values. + +If the config values are insufficient to achieve your desired background +maintenance schedule, then you can create your own schedule. If you run +`crontab -e`, then an editor will load with your user-specific `cron` +schedule. In that editor, you can add your own schedule lines. You could +start by adapting the default schedule listed earlier, or you could read +the crontab(5) documentation for advanced scheduling techniques. Please +do use the full path and `--exec-path` techniques from the default +schedule to ensure you are executing the correct binaries in your +schedule. + + +BACKGROUND MAINTENANCE ON MACOS SYSTEMS +--------------------------------------- + +While macOS technically supports `cron`, using `crontab -e` requires +elevated privileges and the executed process does not have a full user +context. Without a full user context, Git and its credential helpers +cannot access stored credentials, so some maintenance tasks are not +functional. + +Instead, `git maintenance start` interacts with the `launchctl` tool, +which is the recommended way to schedule timed jobs in macOS. Scheduling +maintenance through `git maintenance (start|stop)` requires some +`launchctl` features available only in macOS 10.11 or later. + +Your user-specific scheduled tasks are stored as XML-formatted `.plist` +files in `~/Library/LaunchAgents/`. You can see the currently-registered +tasks using the following command: + +----------------------------------------------------------------------- +$ ls ~/Library/LaunchAgents/org.git-scm.git* +org.git-scm.git.daily.plist +org.git-scm.git.hourly.plist +org.git-scm.git.weekly.plist +----------------------------------------------------------------------- + +One task is registered for each `--schedule=<frequency>` option. To +inspect how the XML format describes each schedule, open one of these +`.plist` files in an editor and inspect the `<array>` element following +the `<key>StartCalendarInterval</key>` element. + +`git maintenance start` will overwrite these files and register the +tasks again with `launchctl`, so any customizations should be done by +creating your own `.plist` files with distinct names. Similarly, the +`git maintenance stop` command will unregister the tasks with `launchctl` +and delete the `.plist` files. + +To create more advanced customizations to your background tasks, see +launchctl.plist(5) for more information. + + +BACKGROUND MAINTENANCE ON WINDOWS SYSTEMS +----------------------------------------- + +Windows does not support `cron` and instead has its own system for +scheduling background tasks. The `git maintenance start` command uses +the `schtasks` command to submit tasks to this system. You can inspect +all background tasks using the Task Scheduler application. The tasks +added by Git have names of the form `Git Maintenance (<frequency>)`. +The Task Scheduler GUI has ways to inspect these tasks, but you can also +export the tasks to XML files and view the details there. + +Note that since Git is a console application, these background tasks +create a console window visible to the current user. This can be changed +manually by selecting the "Run whether user is logged in or not" option +in Task Scheduler. This change requires a password input, which is why +`git maintenance start` does not select it by default. + +If you want to customize the background tasks, please rename the tasks +so future calls to `git maintenance (start|stop)` do not overwrite your +custom tasks. + GIT --- diff --git a/Documentation/git-mergetool--lib.txt b/Documentation/git-mergetool--lib.txt index 4da9d24096..3e8f59ac0e 100644 --- a/Documentation/git-mergetool--lib.txt +++ b/Documentation/git-mergetool--lib.txt @@ -38,6 +38,10 @@ get_merge_tool_cmd:: get_merge_tool_path:: returns the custom path for a merge tool. +initialize_merge_tool:: + bring merge tool specific functions into scope so they can be used or + overridden. + run_merge_tool:: launches a merge tool given the tool name and a true/false flag to indicate whether a merge base is present. diff --git a/Documentation/git-mergetool.txt b/Documentation/git-mergetool.txt index 6b14702e78..e587c7763a 100644 --- a/Documentation/git-mergetool.txt +++ b/Documentation/git-mergetool.txt @@ -99,6 +99,10 @@ success of the resolution after the custom tool has exited. (see linkgit:git-config[1]). To cancel `diff.orderFile`, use `-O/dev/null`. +CONFIGURATION +------------- +include::config/mergetool.txt[] + TEMPORARY FILES --------------- `git mergetool` creates `*.orig` backup files while resolving merges. diff --git a/Documentation/git-mktag.txt b/Documentation/git-mktag.txt index fa6a756123..466a697519 100644 --- a/Documentation/git-mktag.txt +++ b/Documentation/git-mktag.txt @@ -3,7 +3,7 @@ git-mktag(1) NAME ---- -git-mktag - Creates a tag object +git-mktag - Creates a tag object with extra validation SYNOPSIS @@ -13,23 +13,50 @@ SYNOPSIS DESCRIPTION ----------- -Reads a tag contents on standard input and creates a tag object -that can also be used to sign other objects. -The output is the new tag's <object> identifier. +Reads a tag contents on standard input and creates a tag object. The +output is the new tag's <object> identifier. + +This command is mostly equivalent to linkgit:git-hash-object[1] +invoked with `-t tag -w --stdin`. I.e. both of these will create and +write a tag found in `my-tag`: + + git mktag <my-tag + git hash-object -t tag -w --stdin <my-tag + +The difference is that mktag will die before writing the tag if the +tag doesn't pass a linkgit:git-fsck[1] check. + +The "fsck" check done mktag is stricter than what linkgit:git-fsck[1] +would run by default in that all `fsck.<msg-id>` messages are promoted +from warnings to errors (so e.g. a missing "tagger" line is an error). + +Extra headers in the object are also an error under mktag, but ignored +by linkgit:git-fsck[1]. This extra check can be turned off by setting +the appropriate `fsck.<msg-id>` varible: + + git -c fsck.extraHeaderEntry=ignore mktag <my-tag-with-headers + +OPTIONS +------- + +--strict:: + By default mktag turns on the equivalent of + linkgit:git-fsck[1] `--strict` mode. Use `--no-strict` to + disable it. Tag Format ---------- A tag signature file, to be fed to this command's standard input, has a very simple fixed format: four lines of - object <sha1> + object <hash> type <typename> tag <tagname> tagger <tagger> followed by some 'optional' free-form message (some tags created -by older Git may not have `tagger` line). The message, when +by older Git may not have `tagger` line). The message, when it exists, is separated by a blank line from the header. The message part may contain a signature that Git itself doesn't care about, but that can be verified with gpg. diff --git a/Documentation/git-multi-pack-index.txt b/Documentation/git-multi-pack-index.txt index eb0caa0439..ffd601bc17 100644 --- a/Documentation/git-multi-pack-index.txt +++ b/Documentation/git-multi-pack-index.txt @@ -9,7 +9,8 @@ git-multi-pack-index - Write and verify multi-pack-indexes SYNOPSIS -------- [verse] -'git multi-pack-index' [--object-dir=<dir>] [--[no-]progress] <subcommand> +'git multi-pack-index' [--object-dir=<dir>] [--[no-]progress] + [--preferred-pack=<pack>] <subcommand> DESCRIPTION ----------- @@ -30,7 +31,16 @@ OPTIONS The following subcommands are available: write:: - Write a new MIDX file. + Write a new MIDX file. The following options are available for + the `write` sub-command: ++ +-- + --preferred-pack=<pack>:: + Optionally specify the tie-breaking pack used when + multiple packs contain the same object. If not given, + ties are broken in favor of the pack with the lowest + mtime. +-- verify:: Verify the contents of the MIDX file. diff --git a/Documentation/git-p4.txt b/Documentation/git-p4.txt index f89e68b424..38e5257b2a 100644 --- a/Documentation/git-p4.txt +++ b/Documentation/git-p4.txt @@ -762,3 +762,7 @@ IMPLEMENTATION DETAILS message indicating the p4 depot location and change number. This line is used by later 'git p4 sync' operations to know which p4 changes are new. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git-pack-objects.txt b/Documentation/git-pack-objects.txt index 54d715ead1..25d9fbe37a 100644 --- a/Documentation/git-pack-objects.txt +++ b/Documentation/git-pack-objects.txt @@ -85,6 +85,16 @@ base-name:: reference was included in the resulting packfile. This can be useful to send new tags to native Git clients. +--stdin-packs:: + Read the basenames of packfiles (e.g., `pack-1234abcd.pack`) + from the standard input, instead of object names or revision + arguments. The resulting pack contains all objects listed in the + included packs (those not beginning with `^`), excluding any + objects listed in the excluded packs (beginning with `^`). ++ +Incompatible with `--revs`, or options that imply `--revs` (such as +`--all`), with the exception of `--unpacked`, which is compatible. + --window=<n>:: --depth=<n>:: These two options affect how the objects contained in @@ -400,6 +410,17 @@ Note that we pick a single island for each regex to go into, using "last one wins" ordering (which allows repo-specific config to take precedence over user-wide config, and so forth). + +CONFIGURATION +------------- + +Various configuration variables affect packing, see +linkgit:git-config[1] (search for "pack" and "delta"). + +Notably, delta compression is not used on objects larger than the +`core.bigFileThreshold` configuration variable and on files with the +attribute `delta` set to false. + SEE ALSO -------- linkgit:git-rev-list[1] diff --git a/Documentation/git-push.txt b/Documentation/git-push.txt index ab103c82cf..a953c7c387 100644 --- a/Documentation/git-push.txt +++ b/Documentation/git-push.txt @@ -600,7 +600,7 @@ EXAMPLES `git push origin`:: Without additional configuration, pushes the current branch to - the configured upstream (`remote.origin.merge` configuration + the configured upstream (`branch.<name>.merge` configuration variable) if it has the same name as the current branch, and errors out without pushing otherwise. + diff --git a/Documentation/git-range-diff.txt b/Documentation/git-range-diff.txt index 9701c1e5fd..fe350d7f40 100644 --- a/Documentation/git-range-diff.txt +++ b/Documentation/git-range-diff.txt @@ -10,6 +10,7 @@ SYNOPSIS [verse] 'git range-diff' [--color=[<when>]] [--no-color] [<diff-options>] [--no-dual-color] [--creation-factor=<factor>] + [--left-only | --right-only] ( <range1> <range2> | <rev1>...<rev2> | <base> <rev1> <rev2> ) DESCRIPTION @@ -28,6 +29,17 @@ Finally, the list of matching commits is shown in the order of the second commit range, with unmatched commits being inserted just after all of their ancestors have been shown. +There are three ways to specify the commit ranges: + +- `<range1> <range2>`: Either commit range can be of the form + `<base>..<rev>`, `<rev>^!` or `<rev>^-<n>`. See `SPECIFYING RANGES` + in linkgit:gitrevisions[7] for more details. + +- `<rev1>...<rev2>`. This is equivalent to + `<rev2>..<rev1> <rev1>..<rev2>`. + +- `<base> <rev1> <rev2>`: This is equivalent to `<base>..<rev1> + <base>..<rev2>`. OPTIONS ------- @@ -57,6 +69,14 @@ to revert to color all lines according to the outer diff markers See the ``Algorithm`` section below for an explanation why this is needed. +--left-only:: + Suppress commits that are missing from the first specified range + (or the "left range" when using the `<rev1>...<rev2>` format). + +--right-only:: + Suppress commits that are missing from the second specified range + (or the "right range" when using the `<rev1>...<rev2>` format). + --[no-]notes[=<ref>]:: This flag is passed to the `git log` program (see linkgit:git-log[1]) that generates the patches. diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt index a0487b5cc5..55af6fd24e 100644 --- a/Documentation/git-rebase.txt +++ b/Documentation/git-rebase.txt @@ -200,12 +200,6 @@ Alternatively, you can undo the 'git rebase' with git rebase --abort -CONFIGURATION -------------- - -include::config/rebase.txt[] -include::config/sequencer.txt[] - OPTIONS ------- --onto <newbase>:: @@ -593,16 +587,17 @@ See also INCOMPATIBLE OPTIONS below. --autosquash:: --no-autosquash:: - When the commit log message begins with "squash! ..." (or - "fixup! ..."), and there is already a commit in the todo list that - matches the same `...`, automatically modify the todo list of rebase - -i so that the commit marked for squashing comes right after the - commit to be modified, and change the action of the moved commit - from `pick` to `squash` (or `fixup`). A commit matches the `...` if - the commit subject matches, or if the `...` refers to the commit's - hash. As a fall-back, partial matches of the commit subject work, - too. The recommended way to create fixup/squash commits is by using - the `--fixup`/`--squash` options of linkgit:git-commit[1]. + When the commit log message begins with "squash! ..." or "fixup! ..." + or "amend! ...", and there is already a commit in the todo list that + matches the same `...`, automatically modify the todo list of + `rebase -i`, so that the commit marked for squashing comes right after + the commit to be modified, and change the action of the moved commit + from `pick` to `squash` or `fixup` or `fixup -C` respectively. A commit + matches the `...` if the commit subject matches, or if the `...` refers + to the commit's hash. As a fall-back, partial matches of the commit + subject work, too. The recommended way to create fixup/amend/squash + commits is by using the `--fixup`, `--fixup=amend:` or `--fixup=reword:` + and `--squash` options respectively of linkgit:git-commit[1]. + If the `--autosquash` option is enabled by default using the configuration variable `rebase.autoSquash`, this option can be @@ -622,6 +617,14 @@ See also INCOMPATIBLE OPTIONS below. --no-reschedule-failed-exec:: Automatically reschedule `exec` commands that failed. This only makes sense in interactive mode (or when an `--exec` option was provided). ++ +Even though this option applies once a rebase is started, it's set for +the whole rebase at the start based on either the +`rebase.rescheduleFailedExec` configuration (see linkgit:git-config[1] +or "CONFIGURATION" below) or whether this option is +provided. Otherwise an explicit `--no-reschedule-failed-exec` at the +start would be overridden by the presence of +`rebase.rescheduleFailedExec=true` configuration. INCOMPATIBLE OPTIONS -------------------- @@ -887,9 +890,17 @@ If you want to fold two or more commits into one, replace the command "pick" for the second and subsequent commits with "squash" or "fixup". If the commits had different authors, the folded commit will be attributed to the author of the first commit. The suggested commit -message for the folded commit is the concatenation of the commit -messages of the first commit and of those with the "squash" command, -but omits the commit messages of commits with the "fixup" command. +message for the folded commit is the concatenation of the first +commit's message with those identified by "squash" commands, omitting the +messages of commits identified by "fixup" commands, unless "fixup -c" +is used. In that case the suggested commit message is only the message +of the "fixup -c" commit, and an editor is opened allowing you to edit +the message. The contents (patch) of the "fixup -c" commit are still +incorporated into the folded commit. If there is more than one "fixup -c" +commit, the message from the final one is used. You can also use +"fixup -C" to get the same behavior as "fixup -c" except without opening +an editor. + 'git rebase' will stop when "pick" has been replaced with "edit" or when a command fails due to merge errors. When you are done editing @@ -1257,6 +1268,12 @@ merge tlsv1.3 merge cmake ------------ +CONFIGURATION +------------- + +include::config/rebase.txt[] +include::config/sequencer.txt[] + BUGS ---- The todo list presented by the deprecated `--preserve-merges --interactive` diff --git a/Documentation/git-repack.txt b/Documentation/git-repack.txt index 92f146d27d..ef310f362e 100644 --- a/Documentation/git-repack.txt +++ b/Documentation/git-repack.txt @@ -165,9 +165,35 @@ depth is 4095. Pass the `--delta-islands` option to `git-pack-objects`, see linkgit:git-pack-objects[1]. -Configuration +-g=<factor>:: +--geometric=<factor>:: + Arrange resulting pack structure so that each successive pack + contains at least `<factor>` times the number of objects as the + next-largest pack. ++ +`git repack` ensures this by determining a "cut" of packfiles that need +to be repacked into one in order to ensure a geometric progression. It +picks the smallest set of packfiles such that as many of the larger +packfiles (by count of objects contained in that pack) may be left +intact. ++ +Unlike other repack modes, the set of objects to pack is determined +uniquely by the set of packs being "rolled-up"; in other words, the +packs determined to need to be combined in order to restore a geometric +progression. ++ +When `--unpacked` is specified, loose objects are implicitly included in +this "roll-up", without respect to their reachability. This is subject +to change in the future. This option (implying a drastically different +repack mode) is not guaranteed to work with all other combinations of +option to `git repack`. + +CONFIGURATION ------------- +Various configuration variables affect packing, see +linkgit:git-config[1] (search for "pack" and "delta"). + By default, the command passes `--delta-base-offset` option to 'git pack-objects'; this typically results in slightly smaller packs, but the generated packs are incompatible with versions of Git older than @@ -178,6 +204,10 @@ need to set the configuration variable `repack.UseDeltaBaseOffset` to is unaffected by this option as the conversion is performed on the fly as needed in that case. +Delta compression is not used on objects larger than the +`core.bigFileThreshold` configuration variable and on files with the +attribute `delta` set to false. + SEE ALSO -------- linkgit:git-pack-objects[1] diff --git a/Documentation/git-rev-list.txt b/Documentation/git-rev-list.txt index 5da66232dc..20bb8e8217 100644 --- a/Documentation/git-rev-list.txt +++ b/Documentation/git-rev-list.txt @@ -31,6 +31,99 @@ include::rev-list-options.txt[] include::pretty-formats.txt[] +EXAMPLES +-------- + +* Print the list of commits reachable from the current branch. ++ +---------- +git rev-list HEAD +---------- + +* Print the list of commits on this branch, but not present in the + upstream branch. ++ +---------- +git rev-list @{upstream}..HEAD +---------- + +* Format commits with their author and commit message (see also the + porcelain linkgit:git-log[1]). ++ +---------- +git rev-list --format=medium HEAD +---------- + +* Format commits along with their diffs (see also the porcelain + linkgit:git-log[1], which can do this in a single process). ++ +---------- +git rev-list HEAD | +git diff-tree --stdin --format=medium -p +---------- + +* Print the list of commits on the current branch that touched any + file in the `Documentation` directory. ++ +---------- +git rev-list HEAD -- Documentation/ +---------- + +* Print the list of commits authored by you in the past year, on + any branch, tag, or other ref. ++ +---------- +git rev-list --author=you@example.com --since=1.year.ago --all +---------- + +* Print the list of objects reachable from the current branch (i.e., all + commits and the blobs and trees they contain). ++ +---------- +git rev-list --objects HEAD +---------- + +* Compare the disk size of all reachable objects, versus those + reachable from reflogs, versus the total packed size. This can tell + you whether running `git repack -ad` might reduce the repository size + (by dropping unreachable objects), and whether expiring reflogs might + help. ++ +---------- +# reachable objects +git rev-list --disk-usage --objects --all +# plus reflogs +git rev-list --disk-usage --objects --all --reflog +# total disk size used +du -c .git/objects/pack/*.pack .git/objects/??/* +# alternative to du: add up "size" and "size-pack" fields +git count-objects -v +---------- + +* Report the disk size of each branch, not including objects used by the + current branch. This can find outliers that are contributing to a + bloated repository size (e.g., because somebody accidentally committed + large build artifacts). ++ +---------- +git for-each-ref --format='%(refname)' | +while read branch +do + size=$(git rev-list --disk-usage --objects HEAD..$branch) + echo "$size $branch" +done | +sort -n +---------- + +* Compare the on-disk size of branches in one group of refs, excluding + another. If you co-mingle objects from multiple remotes in a single + repository, this can show which remotes are contributing to the + repository size (taking the size of `origin` as a baseline). ++ +---------- +git rev-list --disk-usage --objects --remotes=$suspect --not --remotes=origin +---------- + GIT --- Part of the linkgit:git[1] suite diff --git a/Documentation/git-rev-parse.txt b/Documentation/git-rev-parse.txt index 5013daa6ef..6b8ca085aa 100644 --- a/Documentation/git-rev-parse.txt +++ b/Documentation/git-rev-parse.txt @@ -212,6 +212,18 @@ Options for Files Only the names of the variables are listed, not their value, even if they are set. +--path-format=(absolute|relative):: + Controls the behavior of certain other options. If specified as absolute, the + paths printed by those options will be absolute and canonical. If specified as + relative, the paths will be relative to the current working directory if that + is possible. The default is option specific. ++ +This option may be specified multiple times and affects only the arguments that +follow it on the command line, either to the end of the command line or the next +instance of this option. + +The following options are modified by `--path-format`: + --git-dir:: Show `$GIT_DIR` if defined. Otherwise show the path to the .git directory. The path shown, when relative, is @@ -221,27 +233,9 @@ If `$GIT_DIR` is not defined and the current directory is not detected to lie in a Git repository or work tree print a message to stderr and exit with nonzero status. ---absolute-git-dir:: - Like `--git-dir`, but its output is always the canonicalized - absolute path. - --git-common-dir:: Show `$GIT_COMMON_DIR` if defined, else `$GIT_DIR`. ---is-inside-git-dir:: - When the current working directory is below the repository - directory print "true", otherwise "false". - ---is-inside-work-tree:: - When the current working directory is inside the work tree of the - repository print "true", otherwise "false". - ---is-bare-repository:: - When the repository is bare print "true", otherwise "false". - ---is-shallow-repository:: - When the repository is shallow print "true", otherwise "false". - --resolve-git-dir <path>:: Check if <path> is a valid repository or a gitfile that points at a valid repository, and print the location of the @@ -255,19 +249,9 @@ print a message to stderr and exit with nonzero status. $GIT_OBJECT_DIRECTORY is set to /foo/bar then "git rev-parse --git-path objects/abc" returns /foo/bar/abc. ---show-cdup:: - When the command is invoked from a subdirectory, show the - path of the top-level directory relative to the current - directory (typically a sequence of "../", or an empty string). - ---show-prefix:: - When the command is invoked from a subdirectory, show the - path of the current directory relative to the top-level - directory. - --show-toplevel:: - Show the absolute path of the top-level directory of the working - tree. If there is no working tree, report an error. + Show the (by default, absolute) path of the top-level directory + of the working tree. If there is no working tree, report an error. --show-superproject-working-tree:: Show the absolute path of the root of the superproject's @@ -279,6 +263,36 @@ print a message to stderr and exit with nonzero status. Show the path to the shared index file in split index mode, or empty if not in split-index mode. +The following options are unaffected by `--path-format`: + +--absolute-git-dir:: + Like `--git-dir`, but its output is always the canonicalized + absolute path. + +--is-inside-git-dir:: + When the current working directory is below the repository + directory print "true", otherwise "false". + +--is-inside-work-tree:: + When the current working directory is inside the work tree of the + repository print "true", otherwise "false". + +--is-bare-repository:: + When the repository is bare print "true", otherwise "false". + +--is-shallow-repository:: + When the repository is shallow print "true", otherwise "false". + +--show-cdup:: + When the command is invoked from a subdirectory, show the + path of the top-level directory relative to the current + directory (typically a sequence of "../", or an empty string). + +--show-prefix:: + When the command is invoked from a subdirectory, show the + path of the current directory relative to the top-level + directory. + --show-object-format[=(storage|input|output)]:: Show the object format (hash algorithm) used for the repository for storage inside the `.git` directory, input, or output. For diff --git a/Documentation/git-rm.txt b/Documentation/git-rm.txt index ab750367fd..26e9b28470 100644 --- a/Documentation/git-rm.txt +++ b/Documentation/git-rm.txt @@ -23,7 +23,9 @@ branch, and no updates to their contents can be staged in the index, though that default behavior can be overridden with the `-f` option. When `--cached` is given, the staged content has to match either the tip of the branch or the file on disk, -allowing the file to be removed from just the index. +allowing the file to be removed from just the index. When +sparse-checkouts are in use (see linkgit:git-sparse-checkout[1]), +`git rm` will only remove paths within the sparse-checkout patterns. OPTIONS diff --git a/Documentation/git-shortlog.txt b/Documentation/git-shortlog.txt index fd93cd41e9..c9c7f3065c 100644 --- a/Documentation/git-shortlog.txt +++ b/Documentation/git-shortlog.txt @@ -111,11 +111,11 @@ include::rev-list-options.txt[] MAPPING AUTHORS --------------- -The `.mailmap` feature is used to coalesce together commits by the same -person in the shortlog, where their name and/or email address was -spelled differently. +See linkgit:gitmailmap[5]. -include::mailmap.txt[] +Note that if `git shortlog` is run outside of a repository (to process +log contents on standard input), it will look for a `.mailmap` file in +the current directory. GIT --- diff --git a/Documentation/git-show.txt b/Documentation/git-show.txt index fcf528c1b3..2b1bc7288d 100644 --- a/Documentation/git-show.txt +++ b/Documentation/git-show.txt @@ -45,10 +45,13 @@ include::pretty-options.txt[] include::pretty-formats.txt[] -COMMON DIFF OPTIONS -------------------- +DIFF FORMATTING +--------------- +The options below can be used to change the way `git show` generates +diff output. :git-log: 1 +:diff-merges-default: `dense-combined` include::diff-options.txt[] include::diff-generate-patch.txt[] diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt index a0eeaeb02e..fdcf43f87c 100644 --- a/Documentation/git-sparse-checkout.txt +++ b/Documentation/git-sparse-checkout.txt @@ -45,6 +45,20 @@ To avoid interfering with other worktrees, it first enables the When `--cone` is provided, the `core.sparseCheckoutCone` setting is also set, allowing for better performance with a limited set of patterns (see 'CONE PATTERN SET' below). ++ +Use the `--[no-]sparse-index` option to toggle the use of the sparse +index format. This reduces the size of the index to be more closely +aligned with your sparse-checkout definition. This can have significant +performance advantages for commands such as `git status` or `git add`. +This feature is still experimental. Some commands might be slower with +a sparse index until they are properly integrated with the feature. ++ +**WARNING:** Using a sparse index requires modifying the index in a way +that is not completely understood by external tools. If you have trouble +with this compatibility, then run `git sparse-checkout init --no-sparse-index` +to rewrite your index to not be sparse. Older versions of Git will not +understand the sparse directory entries index extension and may fail to +interact with your repository until it is disabled. 'set':: Write a set of patterns to the sparse-checkout file, as given as diff --git a/Documentation/git-stash.txt b/Documentation/git-stash.txt index 31f1beb65b..a8c8c32f1e 100644 --- a/Documentation/git-stash.txt +++ b/Documentation/git-stash.txt @@ -8,8 +8,8 @@ git-stash - Stash the changes in a dirty working directory away SYNOPSIS -------- [verse] -'git stash' list [<options>] -'git stash' show [<options>] [<stash>] +'git stash' list [<log-options>] +'git stash' show [-u|--include-untracked|--only-untracked] [<diff-options>] [<stash>] 'git stash' drop [-q|--quiet] [<stash>] 'git stash' ( pop | apply ) [--index] [-q|--quiet] [<stash>] 'git stash' branch <branchname> [<stash>] @@ -67,7 +67,7 @@ save [-p|--patch] [-k|--[no-]keep-index] [-u|--include-untracked] [-a|--all] [-q Instead, all non-option arguments are concatenated to form the stash message. -list [<options>]:: +list [<log-options>]:: List the stash entries that you currently have. Each 'stash entry' is listed with its name (e.g. `stash@{0}` is the latest entry, `stash@{1}` is @@ -83,7 +83,7 @@ stash@{1}: On master: 9cc0589... Add git-stash The command takes options applicable to the 'git log' command to control what is shown and how. See linkgit:git-log[1]. -show [<options>] [<stash>]:: +show [-u|--include-untracked|--only-untracked] [<diff-options>] [<stash>]:: Show the changes recorded in the stash entry as a diff between the stashed contents and the commit back when the stash entry was first @@ -91,8 +91,8 @@ show [<options>] [<stash>]:: By default, the command shows the diffstat, but it will accept any format known to 'git diff' (e.g., `git stash show -p stash@{1}` to view the second most recent entry in patch form). - You can use stash.showStat and/or stash.showPatch config variables - to change the default behavior. + You can use stash.showIncludeUntracked, stash.showStat, and + stash.showPatch config variables to change the default behavior. pop [--index] [-q|--quiet] [<stash>]:: @@ -160,10 +160,18 @@ up with `git clean`. -u:: --include-untracked:: - This option is only valid for `push` and `save` commands. +--no-include-untracked:: + When used with the `push` and `save` commands, + all untracked files are also stashed and then cleaned up with + `git clean`. ++ +When used with the `show` command, show the untracked files in the stash +entry as part of the diff. + +--only-untracked:: + This option is only valid for the `show` command. + -All untracked files are also stashed and then cleaned up with -`git clean`. +Show only the untracked files in the stash entry as part of the diff. --index:: This option is only valid for `pop` and `apply` commands. diff --git a/Documentation/git-status.txt b/Documentation/git-status.txt index c0764e850a..83f38e3198 100644 --- a/Documentation/git-status.txt +++ b/Documentation/git-status.txt @@ -130,7 +130,7 @@ ignored, then the directory is not shown, but all contents are shown. --column[=<options>]:: --no-column:: Display untracked files in columns. See configuration variable - column.status for option syntax.`--column` and `--no-column` + `column.status` for option syntax. `--column` and `--no-column` without options are equivalent to 'always' and 'never' respectively. diff --git a/Documentation/git-svn.txt b/Documentation/git-svn.txt index 67b143cc81..d5776ffcfd 100644 --- a/Documentation/git-svn.txt +++ b/Documentation/git-svn.txt @@ -1061,25 +1061,6 @@ with different name spaces. For example: branches = stable/*:refs/remotes/svn/stable/* branches = debug/*:refs/remotes/svn/debug/* -BUGS ----- - -We ignore all SVN properties except svn:executable. Any unhandled -properties are logged to $GIT_DIR/svn/<refname>/unhandled.log - -Renamed and copied directories are not detected by Git and hence not -tracked when committing to SVN. I do not plan on adding support for -this as it's quite difficult and time-consuming to get working for all -the possible corner cases (Git doesn't do it, either). Committing -renamed and copied files is fully supported if they're similar enough -for Git to detect them. - -In SVN, it is possible (though discouraged) to commit changes to a tag -(because a tag is just a directory copy, thus technically the same as a -branch). When cloning an SVN repository, 'git svn' cannot know if such a -commit to a tag will happen in the future. Thus it acts conservatively -and imports all SVN tags as branches, prefixing the tag name with 'tags/'. - CONFIGURATION ------------- @@ -1166,6 +1147,25 @@ $GIT_DIR/svn/\**/.rev_map.*:: if it is missing or not up to date. 'git svn reset' automatically rewinds it. +BUGS +---- + +We ignore all SVN properties except svn:executable. Any unhandled +properties are logged to $GIT_DIR/svn/<refname>/unhandled.log + +Renamed and copied directories are not detected by Git and hence not +tracked when committing to SVN. I do not plan on adding support for +this as it's quite difficult and time-consuming to get working for all +the possible corner cases (Git doesn't do it, either). Committing +renamed and copied files is fully supported if they're similar enough +for Git to detect them. + +In SVN, it is possible (though discouraged) to commit changes to a tag +(because a tag is just a directory copy, thus technically the same as a +branch). When cloning an SVN repository, 'git svn' cannot know if such a +commit to a tag will happen in the future. Thus it acts conservatively +and imports all SVN tags as branches, prefixing the tag name with 'tags/'. + SEE ALSO -------- linkgit:git-rebase[1] diff --git a/Documentation/git-tag.txt b/Documentation/git-tag.txt index 56656d1be6..31a97a1b6c 100644 --- a/Documentation/git-tag.txt +++ b/Documentation/git-tag.txt @@ -134,7 +134,7 @@ options for details. --column[=<options>]:: --no-column:: Display tag listing in columns. See configuration variable - column.tag for option syntax.`--column` and `--no-column` + `column.tag` for option syntax. `--column` and `--no-column` without options are equivalent to 'always' and 'never' respectively. + This option is only applicable when listing tags without annotation lines. diff --git a/Documentation/git-worktree.txt b/Documentation/git-worktree.txt index af06128cc9..f1bb1fa5f5 100644 --- a/Documentation/git-worktree.txt +++ b/Documentation/git-worktree.txt @@ -97,8 +97,9 @@ list:: List details of each working tree. The main working tree is listed first, followed by each of the linked working trees. The output details include whether the working tree is bare, the revision currently checked out, the -branch currently checked out (or "detached HEAD" if none), and "locked" if -the worktree is locked. +branch currently checked out (or "detached HEAD" if none), "locked" if +the worktree is locked, "prunable" if the worktree can be pruned by `prune` +command. lock:: @@ -143,6 +144,11 @@ locate it. Running `repair` within the recently-moved working tree will reestablish the connection. If multiple linked working trees are moved, running `repair` from any working tree with each tree's new `<path>` as an argument, will reestablish the connection to all the specified paths. ++ +If both the main working tree and linked working trees have been moved +manually, then running `repair` in the main working tree and specifying the +new `<path>` of each linked working tree will reestablish all connections +in both directions. unlock:: @@ -226,9 +232,14 @@ This can also be set up as the default behaviour by using the -v:: --verbose:: With `prune`, report all removals. ++ +With `list`, output additional information about worktrees (see below). --expire <time>:: With `prune`, only expire unused working trees older than `<time>`. ++ +With `list`, annotate missing working trees as prunable if they are +older than `<time>`. --reason <string>:: With `lock`, an explanation why the working tree is locked. @@ -367,13 +378,46 @@ $ git worktree list /path/to/other-linked-worktree 1234abc (detached HEAD) ------------ +The command also shows annotations for each working tree, according to its state. +These annotations are: + + * `locked`, if the working tree is locked. + * `prunable`, if the working tree can be pruned via `git worktree prune`. + +------------ +$ git worktree list +/path/to/linked-worktree abcd1234 [master] +/path/to/locked-worktreee acbd5678 (brancha) locked +/path/to/prunable-worktree 5678abc (detached HEAD) prunable +------------ + +For these annotations, a reason might also be available and this can be +seen using the verbose mode. The annotation is then moved to the next line +indented followed by the additional information. + +------------ +$ git worktree list --verbose +/path/to/linked-worktree abcd1234 [master] +/path/to/locked-worktree-no-reason abcd5678 (detached HEAD) locked +/path/to/locked-worktree-with-reason 1234abcd (brancha) + locked: working tree path is mounted on a portable device +/path/to/prunable-worktree 5678abc1 (detached HEAD) + prunable: gitdir file points to non-existent location +------------ + +Note that the annotation is moved to the next line if the additional +information is available, otherwise it stays on the same line as the +working tree itself. + Porcelain Format ~~~~~~~~~~~~~~~~ The porcelain format has a line per attribute. Attributes are listed with a label and value separated by a single space. Boolean attributes (like `bare` and `detached`) are listed as a label only, and are present only -if the value is true. The first attribute of a working tree is always -`worktree`, an empty line indicates the end of the record. For example: +if the value is true. Some attributes (like `locked`) can be listed as a label +only or with a value depending upon whether a reason is available. The first +attribute of a working tree is always `worktree`, an empty line indicates the +end of the record. For example: ------------ $ git worktree list --porcelain @@ -388,6 +432,33 @@ worktree /path/to/other-linked-worktree HEAD 1234abc1234abc1234abc1234abc1234abc1234a detached +worktree /path/to/linked-worktree-locked-no-reason +HEAD 5678abc5678abc5678abc5678abc5678abc5678c +branch refs/heads/locked-no-reason +locked + +worktree /path/to/linked-worktree-locked-with-reason +HEAD 3456def3456def3456def3456def3456def3456b +branch refs/heads/locked-with-reason +locked reason why is locked + +worktree /path/to/linked-worktree-prunable +HEAD 1233def1234def1234def1234def1234def1234b +detached +prunable gitdir file points to non-existent location + +------------ + +If the lock reason contains "unusual" characters such as newline, they +are escaped and the entire reason is quoted as explained for the +configuration variable `core.quotePath` (see linkgit:git-config[1]). +For Example: + +------------ +$ git worktree list --porcelain +... +locked "reason\nwhy is locked" +... ------------ EXAMPLES diff --git a/Documentation/git.txt b/Documentation/git.txt index a6d4ad0818..6dd241ef83 100644 --- a/Documentation/git.txt +++ b/Documentation/git.txt @@ -13,7 +13,7 @@ SYNOPSIS [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path] [-p|--paginate|-P|--no-pager] [--no-replace-objects] [--bare] [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>] - [--super-prefix=<path>] + [--super-prefix=<path>] [--config-env=<name>=<envvar>] <command> [<args>] DESCRIPTION @@ -80,6 +80,28 @@ config file). Including the equals but with an empty value (like `git -c foo.bar= ...`) sets `foo.bar` to the empty string which `git config --type=bool` will convert to `false`. +--config-env=<name>=<envvar>:: + Like `-c <name>=<value>`, give configuration variable + '<name>' a value, where <envvar> is the name of an + environment variable from which to retrieve the value. Unlike + `-c` there is no shortcut for directly setting the value to an + empty string, instead the environment variable itself must be + set to the empty string. It is an error if the `<envvar>` does not exist + in the environment. `<envvar>` may not contain an equals sign + to avoid ambiguity with `<name>` containing one. ++ +This is useful for cases where you want to pass transitory +configuration options to git, but are doing so on OS's where +other processes might be able to read your cmdline +(e.g. `/proc/self/cmdline`), but not your environ +(e.g. `/proc/self/environ`). That behavior is the default on +Linux, but may not be on your system. ++ +Note that this might add security for variables such as +`http.extraHeader` where the sensitive information is part of +the value, but not e.g. `url.<base>.insteadOf` where the +sensitive information can be part of the key. + --exec-path[=<path>]:: Path to wherever your core Git programs are installed. This can also be controlled by setting the GIT_EXEC_PATH @@ -648,6 +670,16 @@ for further details. If this environment variable is set to `0`, git will not prompt on the terminal (e.g., when asking for HTTP authentication). +`GIT_CONFIG_GLOBAL`:: +`GIT_CONFIG_SYSTEM`:: + Take the configuration from the given files instead from global or + system-level configuration files. If `GIT_CONFIG_SYSTEM` is set, the + system config file defined at build time (usually `/etc/gitconfig`) + will not be read. Likewise, if `GIT_CONFIG_GLOBAL` is set, neither + `$HOME/.gitconfig` nor `$XDG_CONFIG_HOME/git/config` will be read. Can + be set to `/dev/null` to skip reading configuration files of the + respective level. + `GIT_CONFIG_NOSYSTEM`:: Whether to skip reading settings from the system-wide `$(prefix)/etc/gitconfig` file. This environment variable can diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt index e84e104f93..83fd4e19a4 100644 --- a/Documentation/gitattributes.txt +++ b/Documentation/gitattributes.txt @@ -845,6 +845,8 @@ patterns are available: - `rust` suitable for source code in the Rust language. +- `scheme` suitable for source code in the Scheme language. + - `tex` suitable for source code for LaTeX documents. @@ -1174,7 +1176,8 @@ tag then no replacement will be done. The placeholders are the same as those for the option `--pretty=format:` of linkgit:git-log[1], except that they need to be wrapped like this: `$Format:PLACEHOLDERS$` in the file. E.g. the string `$Format:%H$` will be replaced by the -commit hash. +commit hash. However, only one `%(describe)` placeholder is expanded +per archive to avoid denial-of-service attacks. Packing objects @@ -1244,6 +1247,12 @@ to: [attr]binary -diff -merge -text ------------ +NOTES +----- + +Git does not follow symbolic links when accessing a `.gitattributes` +file in the working tree. This keeps behavior consistent when the file +is accessed from the index or a tree versus from the filesystem. EXAMPLES -------- diff --git a/Documentation/gitdiffcore.txt b/Documentation/gitdiffcore.txt index c970d9fe43..0d57f86abc 100644 --- a/Documentation/gitdiffcore.txt +++ b/Documentation/gitdiffcore.txt @@ -74,6 +74,7 @@ into another list. There are currently 5 such transformations: - diffcore-merge-broken - diffcore-pickaxe - diffcore-order +- diffcore-rotate These are applied in sequence. The set of filepairs 'git diff-{asterisk}' commands find are used as the input to diffcore-break, and @@ -168,6 +169,26 @@ a similarity score different from the default of 50% by giving a number after the "-M" or "-C" option (e.g. "-M8" to tell it to use 8/10 = 80%). +Note that when rename detection is on but both copy and break +detection are off, rename detection adds a preliminary step that first +checks if files are moved across directories while keeping their +filename the same. If there is a file added to a directory whose +contents is sufficiently similar to a file with the same name that got +deleted from a different directory, it will mark them as renames and +exclude them from the later quadratic step (the one that pairwise +compares all unmatched files to find the "best" matches, determined by +the highest content similarity). So, for example, if a deleted +docs/ext.txt and an added docs/config/ext.txt are similar enough, they +will be marked as a rename and prevent an added docs/ext.md that may +be even more similar to the deleted docs/ext.txt from being considered +as the rename destination in the later step. For this reason, the +preliminary "match same filename" step uses a bit higher threshold to +mark a file pair as a rename and stop considering other candidates for +better matches. At most, one comparison is done per file in this +preliminary pass; so if there are several remaining ext.txt files +throughout the directory hierarchy after exact rename detection, this +preliminary step may be skipped for those files. + Note. When the "-C" option is used with `--find-copies-harder` option, 'git diff-{asterisk}' commands feed unmodified filepairs to diffcore mechanism as well as modified ones. This lets the copy @@ -276,6 +297,26 @@ Documentation t ------------------------------------------------ +diffcore-rotate: For Changing At Which Path Output Starts +--------------------------------------------------------- + +This transformation takes one pathname, and rotates the set of +filepairs so that the filepair for the given pathname comes first, +optionally discarding the paths that come before it. This is used +to implement the `--skip-to` and the `--rotate-to` options. It is +an error when the specified pathname is not in the set of filepairs, +but it is not useful to error out when used with "git log" family of +commands, because it is unreasonable to expect that a given path +would be modified by each and every commit shown by the "git log" +command. For this reason, when used with "git log", the filepair +that sorts the same as, or the first one that sorts after, the given +pathname is where the output starts. + +Use of this transformation combined with diffcore-order will produce +unexpected results, as the input to this transformation is likely +not sorted when diffcore-order is in effect. + + SEE ALSO -------- linkgit:git-diff[1], diff --git a/Documentation/githooks.txt b/Documentation/githooks.txt index 1f3b57d04d..b51959ff94 100644 --- a/Documentation/githooks.txt +++ b/Documentation/githooks.txt @@ -138,7 +138,7 @@ given); `template` (if a `-t` option was given or the configuration option `commit.template` is set); `merge` (if the commit is a merge or a `.git/MERGE_MSG` file exists); `squash` (if a `.git/SQUASH_MSG` file exists); or `commit`, followed by -a commit SHA-1 (if a `-c`, `-C` or `--amend` option was given). +a commit object name (if a `-c`, `-C` or `--amend` option was given). If the exit status is non-zero, `git commit` will abort. @@ -231,19 +231,19 @@ named remote is not being used both values will be the same. Information about what is to be pushed is provided on the hook's standard input with lines of the form: - <local ref> SP <local sha1> SP <remote ref> SP <remote sha1> LF + <local ref> SP <local object name> SP <remote ref> SP <remote object name> LF For instance, if the command +git push origin master:foreign+ were run the hook would receive a line like the following: refs/heads/master 67890 refs/heads/foreign 12345 -although the full, 40-character SHA-1s would be supplied. If the foreign ref -does not yet exist the `<remote SHA-1>` will be 40 `0`. If a ref is to be -deleted, the `<local ref>` will be supplied as `(delete)` and the `<local -SHA-1>` will be 40 `0`. If the local commit was specified by something other -than a name which could be expanded (such as `HEAD~`, or a SHA-1) it will be -supplied as it was originally given. +although the full object name would be supplied. If the foreign ref does not +yet exist the `<remote object name>` will be the all-zeroes object name. If a +ref is to be deleted, the `<local ref>` will be supplied as `(delete)` and the +`<local object name>` will be the all-zeroes object name. If the local commit +was specified by something other than a name which could be expanded (such as +`HEAD~`, or an object name) it will be supplied as it was originally given. If this hook exits with a non-zero status, `git push` will abort without pushing anything. Information about why the push is rejected may be sent @@ -268,7 +268,7 @@ input a line of the format: where `<old-value>` is the old object name stored in the ref, `<new-value>` is the new object name to be stored in the ref and `<ref-name>` is the full name of the ref. -When creating a new ref, `<old-value>` is 40 `0`. +When creating a new ref, `<old-value>` is the all-zeroes object name. If the hook exits with non-zero status, none of the refs will be updated. If the hook exits with zero, updating of individual refs can @@ -473,7 +473,8 @@ reference-transaction This hook is invoked by any Git command that performs reference updates. It executes whenever a reference transaction is prepared, -committed or aborted and may thus get called multiple times. +committed or aborted and may thus get called multiple times. The hook +does not cover symbolic references (but that may change in the future). The hook takes exactly one argument, which is the current state the given reference transaction is in: @@ -492,6 +493,14 @@ receives on standard input a line of the format: <old-value> SP <new-value> SP <ref-name> LF +where `<old-value>` is the old object name passed into the reference +transaction, `<new-value>` is the new object name to be stored in the +ref and `<ref-name>` is the full name of the ref. When force updating +the reference regardless of its current value or when the reference is +to be created anew, `<old-value>` is the all-zeroes object name. To +distinguish these cases, you can inspect the current value of +`<ref-name>` via `git rev-parse`. + The exit status of the hook is ignored for any state except for the "prepared" state. In the "prepared" state, a non-zero exit status will cause the transaction to be aborted. The hook will not be called with @@ -550,7 +559,7 @@ command-dependent arguments may be passed in the future. The hook receives a list of the rewritten commits on stdin, in the format - <old-sha1> SP <new-sha1> [ SP <extra-info> ] LF + <old-object-name> SP <new-object-name> [ SP <extra-info> ] LF The 'extra-info' is again command-dependent. If it is empty, the preceding SP is also omitted. Currently, no commands pass any @@ -566,7 +575,7 @@ rebase:: For the 'squash' and 'fixup' operation, all commits that were squashed are listed as being rewritten to the squashed commit. This means that there will be several lines sharing the same - 'new-sha1'. + 'new-object-name'. + The commits are guaranteed to be listed in the order that they were processed by rebase. diff --git a/Documentation/gitignore.txt b/Documentation/gitignore.txt index d47b1ae296..53e7d5c914 100644 --- a/Documentation/gitignore.txt +++ b/Documentation/gitignore.txt @@ -149,11 +149,15 @@ not tracked by Git remain untracked. To stop tracking a file that is currently tracked, use 'git rm --cached'. +Git does not follow symbolic links when accessing a `.gitignore` file in +the working tree. This keeps behavior consistent when the file is +accessed from the index or a tree versus from the filesystem. + EXAMPLES -------- - The pattern `hello.*` matches any file or folder - whose name begins with `hello`. If one wants to restrict + whose name begins with `hello.`. If one wants to restrict this only to the directory and not in its subdirectories, one can prepend the pattern with a slash, i.e. `/hello.*`; the pattern now matches `hello.txt`, `hello.c` but not diff --git a/Documentation/gitmailmap.txt b/Documentation/gitmailmap.txt new file mode 100644 index 0000000000..06f4af93fe --- /dev/null +++ b/Documentation/gitmailmap.txt @@ -0,0 +1,130 @@ +gitmailmap(5) +============= + +NAME +---- +gitmailmap - Map author/committer names and/or E-Mail addresses + +SYNOPSIS +-------- +$GIT_WORK_TREE/.mailmap + + +DESCRIPTION +----------- + +If the file `.mailmap` exists at the toplevel of the repository, or at +the location pointed to by the `mailmap.file` or `mailmap.blob` +configuration options (see linkgit:git-config[1]), it +is used to map author and committer names and email addresses to +canonical real names and email addresses. + + +SYNTAX +------ + +The '#' character begins a comment to the end of line, blank lines +are ignored. + +In the simple form, each line in the file consists of the canonical +real name of an author, whitespace, and an email address used in the +commit (enclosed by '<' and '>') to map to the name. For example: +-- + Proper Name <commit@email.xx> +-- + +The more complex forms are: +-- + <proper@email.xx> <commit@email.xx> +-- +which allows mailmap to replace only the email part of a commit, and: +-- + Proper Name <proper@email.xx> <commit@email.xx> +-- +which allows mailmap to replace both the name and the email of a +commit matching the specified commit email address, and: +-- + Proper Name <proper@email.xx> Commit Name <commit@email.xx> +-- +which allows mailmap to replace both the name and the email of a +commit matching both the specified commit name and email address. + +Both E-Mails and names are matched case-insensitively. For example +this would also match the 'Commit Name <commit@email.xx>' above: +-- + Proper Name <proper@email.xx> CoMmIt NaMe <CoMmIt@EmAiL.xX> +-- + +NOTES +----- + +Git does not follow symbolic links when accessing a `.mailmap` file in +the working tree. This keeps behavior consistent when the file is +accessed from the index or a tree versus from the filesystem. + +EXAMPLES +-------- + +Your history contains commits by two authors, Jane +and Joe, whose names appear in the repository under several forms: + +------------ +Joe Developer <joe@example.com> +Joe R. Developer <joe@example.com> +Jane Doe <jane@example.com> +Jane Doe <jane@laptop.(none)> +Jane D. <jane@desktop.(none)> +------------ + +Now suppose that Joe wants his middle name initial used, and Jane +prefers her family name fully spelled out. A `.mailmap` file to +correct the names would look like: + +------------ +Joe R. Developer <joe@example.com> +Jane Doe <jane@example.com> +Jane Doe <jane@desktop.(none)> +------------ + +Note that there's no need to map the name for '<jane@laptop.(none)>' to +only correct the names. However, leaving the obviously broken +'<jane@laptop.(none)>' and '<jane@desktop.(none)>' E-Mails as-is is +usually not what you want. A `.mailmap` file which also corrects those +is: + +------------ +Joe R. Developer <joe@example.com> +Jane Doe <jane@example.com> <jane@laptop.(none)> +Jane Doe <jane@example.com> <jane@desktop.(none)> +------------ + +Finally, let's say that Joe and Jane shared an E-Mail address, but not +a name, e.g. by having these two commits in the history generated by a +bug reporting system. I.e. names appearing in history as: + +------------ +Joe <bugs@example.com> +Jane <bugs@example.com> +------------ + +A full `.mailmap` file which also handles those cases (an addition of +two lines to the above example) would be: + +------------ +Joe R. Developer <joe@example.com> +Jane Doe <jane@example.com> <jane@laptop.(none)> +Jane Doe <jane@example.com> <jane@desktop.(none)> +Joe R. Developer <joe@example.com> Joe <bugs@example.com> +Jane Doe <jane@example.com> Jane <bugs@example.com> +------------ + + + +SEE ALSO +-------- +linkgit:git-check-mailmap[1] + + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/gitmodules.txt b/Documentation/gitmodules.txt index 8e333dde1b..dcee09b500 100644 --- a/Documentation/gitmodules.txt +++ b/Documentation/gitmodules.txt @@ -98,6 +98,14 @@ submodule.<name>.shallow:: shallow clone (with a history depth of 1) unless the user explicitly asks for a non-shallow clone. +NOTES +----- + +Git does not allow the `.gitmodules` file within a working tree to be a +symbolic link, and will refuse to check out such a tree entry. This +keeps behavior consistent when the file is accessed from the index or a +tree versus from the filesystem, and helps Git reliably enforce security +checks of the file contents. EXAMPLES -------- diff --git a/Documentation/gitnamespaces.txt b/Documentation/gitnamespaces.txt index b614969ad2..1c8d2ecc35 100644 --- a/Documentation/gitnamespaces.txt +++ b/Documentation/gitnamespaces.txt @@ -62,3 +62,7 @@ git clone ext::'git --namespace=foo %s /tmp/prefixed.git' ---------- include::transfer-data-leaks.txt[] + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/gitweb.conf.txt b/Documentation/gitweb.conf.txt index 7963a79ba9..34b1d6e224 100644 --- a/Documentation/gitweb.conf.txt +++ b/Documentation/gitweb.conf.txt @@ -751,6 +751,17 @@ default font sizes or lineheights are changed (e.g. via adding extra CSS stylesheet in `@stylesheets`), it may be appropriate to change these values. +email-privacy:: + Redact e-mail addresses from the generated HTML, etc. content. + This obscures e-mail addresses retrieved from the author/committer + and comment sections of the Git log. + It is meant to hinder web crawlers that harvest and abuse addresses. + Such crawlers may not respect robots.txt. + Note that users and user tools also see the addresses as redacted. + If Gitweb is not the final step in a workflow then subsequent steps + may misbehave because of the redacted information they receive. + Disabled by default. + highlight:: Server-side syntax highlight support in "blob" view. It requires `$highlight_bin` program to be available (see the description of diff --git a/Documentation/howto/coordinate-embargoed-releases.txt b/Documentation/howto/coordinate-embargoed-releases.txt new file mode 100644 index 0000000000..601aae88e9 --- /dev/null +++ b/Documentation/howto/coordinate-embargoed-releases.txt @@ -0,0 +1,131 @@ +Content-type: text/asciidoc +Abstract: When a critical vulnerability is discovered and fixed, we follow this + script to coordinate a public release. + +How we coordinate embargoed releases +==================================== + +To protect Git users from critical vulnerabilities, we do not just release +fixed versions like regular maintenance releases. Instead, we coordinate +releases with packagers, keeping the fixes under an embargo until the release +date. That way, users will have a chance to upgrade on that date, no matter +what Operating System or distribution they run. + +Open a Security Advisory draft +------------------------------ + +The first step is to https://github.com/git/git/security/advisories/new[open an +advisory]. Technically, it is not necessary, but it is convenient and saves a +bit of hassle. This advisory can also be used to obtain the CVE number and it +will give us a private fork associated with it that can be used to collaborate +on a fix. + +Release date of the embargoed version +------------------------------------- + +If the vulnerability affects Windows users, we want to have our friends over at +Visual Studio on board. This means we need to target a "Patch Tuesday" (i.e. a +second Tuesday of the month), at the minimum three weeks from heads-up to +coordinated release. + +If the vulnerability affects the server side, or can benefit from scans on the +server side (i.e. if `git fsck` can detect an attack), it is important to give +all involved Git repository hosting sites enough time to scan all of those +repositories. + +Notifying the Linux distributions +--------------------------------- + +At most two weeks before release date, we need to send a notification to +distros@vs.openwall.org, preferably less than 7 days before the release date. +This will reach most (all?) Linux distributions. See an example below, and the +guidelines for this mailing list at +https://oss-security.openwall.org/wiki/mailing-lists/distros#how-to-use-the-lists[here]. + +Once the version has been published, we send a note about that to oss-security. +As an example, see https://www.openwall.com/lists/oss-security/2019/12/13/1[the +v2.24.1 mail]; +https://oss-security.openwall.org/wiki/mailing-lists/oss-security[Here] are +their guidelines. + +The mail to oss-security should also describe the exploit, and give credit to +the reporter(s): security researchers still receive too little respect for the +invaluable service they provide, and public credit goes a long way to keep them +paid by their respective organizations. + +Technically, describing any exploit can be delayed up to 7 days, but we usually +refrain from doing that, including it right away. + +As a courtesy we typically attach a Git bundle (as `.tar.xz` because the list +will drop `.bundle` attachments) in the mail to distros@ so that the involved +parties can take care of integrating/backporting them. This bundle is typically +created using a command like this: + + git bundle create cve-xxx.bundle ^origin/master vA.B.C vD.E.F + tar cJvf cve-xxx.bundle.tar.xz cve-xxx.bundle + +Example mail to distros@vs.openwall.org +--------------------------------------- + +.... +To: distros@vs.openwall.org +Cc: git-security@googlegroups.com, <other people involved in the report/fix> +Subject: [vs] Upcoming Git security fix release + +Team, + +The Git project will release new versions on <date> at 10am Pacific Time or +soon thereafter. I have attached a Git bundle (embedded in a `.tar.xz` to avoid +it being dropped) which you can fetch into a clone of +https://github.com/git/git via `git fetch --tags /path/to/cve-xxx.bundle`, +containing the tags for versions <versions>. + +You can verify with `git tag -v <tag>` that the versions were signed by +the Git maintainer, using the same GPG key as e.g. v2.24.0. + +Please use these tags to prepare `git` packages for your various +distributions, using the appropriate tagged versions. The added test cases +help verify the correctness. + +The addressed issues are: + +<list of CVEs with a short description, typically copy/pasted from Git's +release notes, usually demo exploit(s), too> + +Credit for finding the vulnerability goes to <reporter>, credit for fixing +it goes to <developer>. + +Thanks, +<name> + +.... + +Example mail to oss-security@lists.openwall.com +----------------------------------------------- + +.... +To: oss-security@lists.openwall.com +Cc: git-security@googlegroups.com, <other people involved in the report/fix> +Subject: git: <copy from security advisory> + +Team, + +The Git project released new versions on <date>, addressing <CVE>. + +All supported platforms are affected in one way or another, and all Git +versions all the way back to <version> are affected. The fixed versions are: +<versions>. + +Link to the announcement: <link to lore.kernel.org/git> + +We highly recommend to upgrade. + +The addressed issues are: +* <list of CVEs and their explanations, along with demo exploits> + +Credit for finding the vulnerability goes to <reporter>, credit for fixing +it goes to <developer>. + +Thanks, +<name> +.... diff --git a/Documentation/i18n.txt b/Documentation/i18n.txt index 7e36e5b55b..6c6baeeeb7 100644 --- a/Documentation/i18n.txt +++ b/Documentation/i18n.txt @@ -38,7 +38,7 @@ mind. a warning if the commit log message given to it does not look like a valid UTF-8 string, unless you explicitly say your project uses a legacy encoding. The way to say this is to - have i18n.commitencoding in `.git/config` file, like this: + have `i18n.commitEncoding` in `.git/config` file, like this: + ------------ [i18n] diff --git a/Documentation/lint-gitlink.perl b/Documentation/lint-gitlink.perl index 476cc30b83..b22a367844 100755 --- a/Documentation/lint-gitlink.perl +++ b/Documentation/lint-gitlink.perl @@ -1,71 +1,67 @@ #!/usr/bin/perl -use File::Find; -use Getopt::Long; +use strict; +use warnings; -my $basedir = "."; -GetOptions("basedir=s" => \$basedir) - or die("Cannot parse command line arguments\n"); +# Parse arguments, a simple state machine for input like: +# +# howto/*.txt config/*.txt --section=1 git.txt git-add.txt [...] --to-lint git-add.txt a-file.txt [...] +my %TXT; +my %SECTION; +my $section; +my $lint_these = 0; +for my $arg (@ARGV) { + if (my ($sec) = $arg =~ /^--section=(\d+)$/s) { + $section = $sec; + next; + } -my $found_errors = 0; + my ($name) = $arg =~ /^(.*?)\.txt$/s; + unless (defined $section) { + $TXT{$name} = $arg; + next; + } -sub report { - my ($where, $what, $error) = @_; - print "$where: $error: $what\n"; - $found_errors = 1; + $SECTION{$name} = $section; } -sub grab_section { - my ($page) = @_; - open my $fh, "<", "$basedir/$page.txt"; - my $firstline = <$fh>; - chomp $firstline; - close $fh; - my ($section) = ($firstline =~ /.*\((\d)\)$/); - return $section; +my $exit_code = 0; +sub report { + my ($pos, $line, $target, $msg) = @_; + substr($line, $pos) = "' <-- HERE"; + $line =~ s/^\s+//; + print "$ARGV:$.: error: $target: $msg, shown with 'HERE' below:\n"; + print "$ARGV:$.:\t'$line\n"; + $exit_code = 1; } -sub lint { - my ($file) = @_; - open my $fh, "<", $file - or return; - while (<$fh>) { - my $where = "$file:$."; - while (s/linkgit:((.*?)\[(\d)\])//) { - my ($target, $page, $section) = ($1, $2, $3); +@ARGV = sort values %TXT; +die "BUG: Nothing to process!" unless @ARGV; +while (<>) { + my $line = $_; + while ($line =~ m/linkgit:((.*?)\[(\d)\])/g) { + my $pos = pos $line; + my ($target, $page, $section) = ($1, $2, $3); - # De-AsciiDoc - $page =~ s/{litdd}/--/g; + # De-AsciiDoc + $page =~ s/{litdd}/--/g; - if ($page !~ /^git/) { - report($where, $target, "nongit link"); - next; - } - if (! -f "$basedir/$page.txt") { - report($where, $target, "no such source"); - next; - } - $real_section = grab_section($page); - if ($real_section != $section) { - report($where, $target, - "wrong section (should be $real_section)"); - next; - } + if (!exists $TXT{$page}) { + report($pos, $line, $target, "link outside of our own docs"); + next; + } + if (!exists $SECTION{$page}) { + report($pos, $line, $target, "link outside of our sectioned docs"); + next; + } + my $real_section = $SECTION{$page}; + if ($section != $SECTION{$page}) { + report($pos, $line, $target, "wrong section (should be $real_section)"); + next; } } - close $fh; -} - -sub lint_it { - lint($File::Find::name) if -f && /\.txt$/; -} - -if (!@ARGV) { - find({ wanted => \&lint_it, no_chdir => 1 }, $basedir); -} else { - for (@ARGV) { - lint($_); - } + # this resets our $. for each file + close ARGV if eof; } -exit $found_errors; +exit $exit_code; diff --git a/Documentation/lint-man-end-blurb.perl b/Documentation/lint-man-end-blurb.perl new file mode 100755 index 0000000000..d69312e5db --- /dev/null +++ b/Documentation/lint-man-end-blurb.perl @@ -0,0 +1,24 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +my $exit_code = 0; +sub report { + my ($target, $msg) = @_; + print "error: $target: $msg\n"; + $exit_code = 1; +} + +local $/; +while (my $slurp = <>) { + report($ARGV, "has no 'Part of the linkgit:git[1] suite' end blurb") + unless $slurp =~ m[ + ^GIT\n + ---\n + \QPart of the linkgit:git[1] suite\E \n + \z + ]mx; +} + +exit $exit_code; diff --git a/Documentation/lint-man-section-order.perl b/Documentation/lint-man-section-order.perl new file mode 100755 index 0000000000..b05f9156dd --- /dev/null +++ b/Documentation/lint-man-section-order.perl @@ -0,0 +1,105 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +my %SECTIONS; +{ + my $order = 0; + %SECTIONS = ( + 'NAME' => { + required => 1, + order => $order++, + }, + 'SYNOPSIS' => { + required => 1, + order => $order++, + }, + 'DESCRIPTION' => { + required => 1, + order => $order++, + }, + 'OPTIONS' => { + order => $order++, + required => 0, + }, + 'CONFIGURATION' => { + order => $order++, + }, + 'BUGS' => { + order => $order++, + }, + 'SEE ALSO' => { + order => $order++, + }, + 'GIT' => { + required => 1, + order => $order++, + }, + ); +} +my $SECTION_RX = do { + my ($names) = join "|", keys %SECTIONS; + qr/^($names)$/s; +}; + +my $exit_code = 0; +sub report { + my ($msg) = @_; + print "$ARGV:$.: $msg\n"; + $exit_code = 1; +} + +my $last_was_section; +my @actual_order; +while (my $line = <>) { + chomp $line; + if ($line =~ $SECTION_RX) { + push @actual_order => $line; + $last_was_section = 1; + # Have no "last" section yet, processing NAME + next if @actual_order == 1; + + my @expected_order = sort { + $SECTIONS{$a}->{order} <=> $SECTIONS{$b}->{order} + } @actual_order; + + my $expected_last = $expected_order[-2]; + my $actual_last = $actual_order[-2]; + if ($actual_last ne $expected_last) { + report("section '$line' incorrectly ordered, comes after '$actual_last'"); + } + next; + } + if ($last_was_section) { + my $last_section = $actual_order[-1]; + if (length $last_section ne length $line) { + report("dashes under '$last_section' should match its length!"); + } + if ($line !~ /^-+$/) { + report("dashes under '$last_section' should be '-' dashes!"); + } + $last_was_section = 0; + } + + if (eof) { + # We have both a hash and an array to consider, for + # convenience + my %actual_sections; + @actual_sections{@actual_order} = (); + + for my $section (sort keys %SECTIONS) { + next if !$SECTIONS{$section}->{required} or exists $actual_sections{$section}; + report("has no required '$section' section!"); + } + + # Reset per-file state + { + @actual_order = (); + # this resets our $. for each file + close ARGV; + } + } +} + +exit $exit_code; diff --git a/Documentation/mailmap.txt b/Documentation/mailmap.txt deleted file mode 100644 index 4a8c276529..0000000000 --- a/Documentation/mailmap.txt +++ /dev/null @@ -1,75 +0,0 @@ -If the file `.mailmap` exists at the toplevel of the repository, or at -the location pointed to by the mailmap.file or mailmap.blob -configuration options, it -is used to map author and committer names and email addresses to -canonical real names and email addresses. - -In the simple form, each line in the file consists of the canonical -real name of an author, whitespace, and an email address used in the -commit (enclosed by '<' and '>') to map to the name. For example: --- - Proper Name <commit@email.xx> --- - -The more complex forms are: --- - <proper@email.xx> <commit@email.xx> --- -which allows mailmap to replace only the email part of a commit, and: --- - Proper Name <proper@email.xx> <commit@email.xx> --- -which allows mailmap to replace both the name and the email of a -commit matching the specified commit email address, and: --- - Proper Name <proper@email.xx> Commit Name <commit@email.xx> --- -which allows mailmap to replace both the name and the email of a -commit matching both the specified commit name and email address. - -Example 1: Your history contains commits by two authors, Jane -and Joe, whose names appear in the repository under several forms: - ------------- -Joe Developer <joe@example.com> -Joe R. Developer <joe@example.com> -Jane Doe <jane@example.com> -Jane Doe <jane@laptop.(none)> -Jane D. <jane@desktop.(none)> ------------- - -Now suppose that Joe wants his middle name initial used, and Jane -prefers her family name fully spelled out. A proper `.mailmap` file -would look like: - ------------- -Jane Doe <jane@desktop.(none)> -Joe R. Developer <joe@example.com> ------------- - -Note how there is no need for an entry for `<jane@laptop.(none)>`, because the -real name of that author is already correct. - -Example 2: Your repository contains commits from the following -authors: - ------------- -nick1 <bugs@company.xx> -nick2 <bugs@company.xx> -nick2 <nick2@company.xx> -santa <me@company.xx> -claus <me@company.xx> -CTO <cto@coompany.xx> ------------- - -Then you might want a `.mailmap` file that looks like: ------------- -<cto@company.xx> <cto@coompany.xx> -Some Dude <some@dude.xx> nick1 <bugs@company.xx> -Other Author <other@author.xx> nick2 <bugs@company.xx> -Other Author <other@author.xx> <nick2@company.xx> -Santa Claus <santa.claus@northpole.xx> <me@company.xx> ------------- - -Use hash '#' for comments that are either on their own line, or after -the email address. diff --git a/Documentation/pretty-formats.txt b/Documentation/pretty-formats.txt index 84bbc7439a..ef6bd420ae 100644 --- a/Documentation/pretty-formats.txt +++ b/Documentation/pretty-formats.txt @@ -190,6 +190,8 @@ The placeholders are: '%ai':: author date, ISO 8601-like format '%aI':: author date, strict ISO 8601 format '%as':: author date, short format (`YYYY-MM-DD`) +'%ah':: author date, human style (like the `--date=human` option of + linkgit:git-rev-list[1]) '%cn':: committer name '%cN':: committer name (respecting .mailmap, see linkgit:git-shortlog[1] or linkgit:git-blame[1]) @@ -206,8 +208,23 @@ The placeholders are: '%ci':: committer date, ISO 8601-like format '%cI':: committer date, strict ISO 8601 format '%cs':: committer date, short format (`YYYY-MM-DD`) +'%ch':: committer date, human style (like the `--date=human` option of + linkgit:git-rev-list[1]) '%d':: ref names, like the --decorate option of linkgit:git-log[1] '%D':: ref names without the " (", ")" wrapping. +'%(describe[:options])':: human-readable name, like + linkgit:git-describe[1]; empty string for + undescribable commits. The `describe` string + may be followed by a colon and zero or more + comma-separated options. Descriptions can be + inconsistent when tags are added or removed at + the same time. ++ +** 'match=<pattern>': Only consider tags matching the given + `glob(7)` pattern, excluding the "refs/tags/" prefix. +** 'exclude=<pattern>': Do not consider tags matching the given + `glob(7)` pattern, excluding the "refs/tags/" prefix. + '%S':: ref name given on the command line by which the commit was reached (like `git log --source`), only works with `git log` '%e':: encoding @@ -252,7 +269,15 @@ endif::git-rev-list[] interpreted by linkgit:git-interpret-trailers[1]. The `trailers` string may be followed by a colon - and zero or more comma-separated options: + and zero or more comma-separated options. + If any option is provided multiple times the + last occurrence wins. ++ +The boolean options accept an optional value `[=<BOOL>]`. The values +`true`, `false`, `on`, `off` etc. are all accepted. See the "boolean" +sub-section in "EXAMPLES" in linkgit:git-config[1]. If a boolean +option is given with no value, it's enabled. ++ ** 'key=<K>': only show trailers with specified key. Matching is done case-insensitively and trailing colon is optional. If option is given multiple times trailer lines matching any of the keys are @@ -261,27 +286,25 @@ endif::git-rev-list[] desired it can be disabled with `only=false`. E.g., `%(trailers:key=Reviewed-by)` shows trailer lines with key `Reviewed-by`. -** 'only[=val]': select whether non-trailer lines from the trailer - block should be included. The `only` keyword may optionally be - followed by an equal sign and one of `true`, `on`, `yes` to omit or - `false`, `off`, `no` to show the non-trailer lines. If option is - given without value it is enabled. If given multiple times the last - value is used. +** 'only[=<BOOL>]': select whether non-trailer lines from the trailer + block should be included. ** 'separator=<SEP>': specify a separator inserted between trailer lines. When this option is not given each trailer line is terminated with a line feed character. The string SEP may contain the literal formatting codes described above. To use comma as separator one must use `%x2C` as it would otherwise be parsed as - next option. If separator option is given multiple times only the - last one is used. E.g., `%(trailers:key=Ticket,separator=%x2C )` + next option. E.g., `%(trailers:key=Ticket,separator=%x2C )` shows all trailer lines whose key is "Ticket" separated by a comma and a space. -** 'unfold[=val]': make it behave as if interpret-trailer's `--unfold` - option was given. In same way as to for `only` it can be followed - by an equal sign and explicit value. E.g., +** 'unfold[=<BOOL>]': make it behave as if interpret-trailer's `--unfold` + option was given. E.g., `%(trailers:only,unfold=true)` unfolds and shows all trailer lines. -** 'valueonly[=val]': skip over the key part of the trailer line and only - show the value part. Also this optionally allows explicit value. +** 'keyonly[=<BOOL>]': only show the key part of the trailer. +** 'valueonly[=<BOOL>]': only show the value part of the trailer. +** 'key_value_separator=<SEP>': specify a separator inserted between + trailer lines. When this option is not given each trailer key-value + pair is separated by ": ". Otherwise it shares the same semantics + as 'separator=<SEP>' above. NOTE: Some placeholders may depend on other options given to the revision traversal engine. For example, the `%g*` reflog options will diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt index 002379056a..5bf2a85f69 100644 --- a/Documentation/rev-list-options.txt +++ b/Documentation/rev-list-options.txt @@ -129,6 +129,11 @@ parents) and `--max-parents=-1` (negative numbers denote no upper limit). adjusting to updated upstream from time to time, and this option allows you to ignore the individual commits brought in to your history by such a merge. +ifdef::git-log[] ++ +This option also changes default diff format for merge commits +to `first-parent`, see `--diff-merges=first-parent` for details. +endif::git-log[] --not:: Reverses the meaning of the '{caret}' prefix (or lack thereof) @@ -222,6 +227,15 @@ ifdef::git-rev-list[] test the exit status to see if a range of objects is fully connected (or not). It is faster than redirecting stdout to `/dev/null` as the output does not have to be formatted. + +--disk-usage:: + Suppress normal output; instead, print the sum of the bytes used + for on-disk storage by the selected commits or objects. This is + equivalent to piping the output into `git cat-file + --batch-check='%(objectsize:disk)'`, except that it runs much + faster (especially with `--use-bitmap-index`). See the `CAVEATS` + section in linkgit:git-cat-file[1] for the limitations of what + "on-disk storage" means. endif::git-rev-list[] --cherry-mark:: @@ -878,6 +892,9 @@ or units. n may be zero. The suffixes k, m, and g can be used to name units in KiB, MiB, or GiB. For example, 'blob:limit=1k' is the same as 'blob:limit=1024'. + +The form '--filter=object:type=(tag|commit|tree|blob)' omits all objects +which are not of the requested type. ++ The form '--filter=sparse:oid=<blob-ish>' uses a sparse-checkout specification contained in the blob (or blob-expression) '<blob-ish>' to omit blobs that would not be not required for a sparse checkout on @@ -916,6 +933,11 @@ equivalent. --no-filter:: Turn off any previous `--filter=` argument. +--filter-provided-objects:: + Filter the list of explicitly provided objects, which would otherwise + always be printed even if they did not match any of the filters. Only + useful with `--filter=`. + --filter-print-omitted:: Only useful with `--filter=`; prints a list of the objects omitted by the filter. Object IDs are prefixed with a ``~'' character. diff --git a/Documentation/technical/api-error-handling.txt b/Documentation/technical/api-error-handling.txt index ceeedd485c..8be4f4d0d6 100644 --- a/Documentation/technical/api-error-handling.txt +++ b/Documentation/technical/api-error-handling.txt @@ -1,8 +1,11 @@ Error reporting in git ====================== -`die`, `usage`, `error`, and `warning` report errors of various -kinds. +`BUG`, `die`, `usage`, `error`, and `warning` report errors of +various kinds. + +- `BUG` is for failed internal assertions that should never happen, + i.e. a bug in git itself. - `die` is for fatal application errors. It prints a message to the user and exits with status 128. @@ -20,6 +23,9 @@ kinds. without running into too many problems. Like `error`, it returns -1 after reporting the situation to the caller. +These reports will be logged via the trace2 facility. See the "error" +event in link:api-trace2.txt[trace2 API]. + Customizable error handlers --------------------------- diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt index c65ffafc48..3f52f981a2 100644 --- a/Documentation/technical/api-trace2.txt +++ b/Documentation/technical/api-trace2.txt @@ -465,7 +465,7 @@ completed.) ------------ `"error"`:: - This event is emitted when one of the `error()`, `die()`, + This event is emitted when one of the `BUG()`, `error()`, `die()`, `warning()`, or `usage()` functions are called. + ------------ diff --git a/Documentation/technical/chunk-format.txt b/Documentation/technical/chunk-format.txt new file mode 100644 index 0000000000..593614fced --- /dev/null +++ b/Documentation/technical/chunk-format.txt @@ -0,0 +1,116 @@ +Chunk-based file formats +======================== + +Some file formats in Git use a common concept of "chunks" to describe +sections of the file. This allows structured access to a large file by +scanning a small "table of contents" for the remaining data. This common +format is used by the `commit-graph` and `multi-pack-index` files. See +link:technical/pack-format.html[the `multi-pack-index` format] and +link:technical/commit-graph-format.html[the `commit-graph` format] for +how they use the chunks to describe structured data. + +A chunk-based file format begins with some header information custom to +that format. That header should include enough information to identify +the file type, format version, and number of chunks in the file. From this +information, that file can determine the start of the chunk-based region. + +The chunk-based region starts with a table of contents describing where +each chunk starts and ends. This consists of (C+1) rows of 12 bytes each, +where C is the number of chunks. Consider the following table: + + | Chunk ID (4 bytes) | Chunk Offset (8 bytes) | + |--------------------|------------------------| + | ID[0] | OFFSET[0] | + | ... | ... | + | ID[C] | OFFSET[C] | + | 0x0000 | OFFSET[C+1] | + +Each row consists of a 4-byte chunk identifier (ID) and an 8-byte offset. +Each integer is stored in network-byte order. + +The chunk identifier `ID[i]` is a label for the data stored within this +fill from `OFFSET[i]` (inclusive) to `OFFSET[i+1]` (exclusive). Thus, the +size of the `i`th chunk is equal to the difference between `OFFSET[i+1]` +and `OFFSET[i]`. This requires that the chunk data appears contiguously +in the same order as the table of contents. + +The final entry in the table of contents must be four zero bytes. This +confirms that the table of contents is ending and provides the offset for +the end of the chunk-based data. + +Note: The chunk-based format expects that the file contains _at least_ a +trailing hash after `OFFSET[C+1]`. + +Functions for working with chunk-based file formats are declared in +`chunk-format.h`. Using these methods provide extra checks that assist +developers when creating new file formats. + +Writing chunk-based file formats +-------------------------------- + +To write a chunk-based file format, create a `struct chunkfile` by +calling `init_chunkfile()` and pass a `struct hashfile` pointer. The +caller is responsible for opening the `hashfile` and writing header +information so the file format is identifiable before the chunk-based +format begins. + +Then, call `add_chunk()` for each chunk that is intended for write. This +populates the `chunkfile` with information about the order and size of +each chunk to write. Provide a `chunk_write_fn` function pointer to +perform the write of the chunk data upon request. + +Call `write_chunkfile()` to write the table of contents to the `hashfile` +followed by each of the chunks. This will verify that each chunk wrote +the expected amount of data so the table of contents is correct. + +Finally, call `free_chunkfile()` to clear the `struct chunkfile` data. The +caller is responsible for finalizing the `hashfile` by writing the trailing +hash and closing the file. + +Reading chunk-based file formats +-------------------------------- + +To read a chunk-based file format, the file must be opened as a +memory-mapped region. The chunk-format API expects that the entire file +is mapped as a contiguous memory region. + +Initialize a `struct chunkfile` pointer with `init_chunkfile(NULL)`. + +After reading the header information from the beginning of the file, +including the chunk count, call `read_table_of_contents()` to populate +the `struct chunkfile` with the list of chunks, their offsets, and their +sizes. + +Extract the data information for each chunk using `pair_chunk()` or +`read_chunk()`: + +* `pair_chunk()` assigns a given pointer with the location inside the + memory-mapped file corresponding to that chunk's offset. If the chunk + does not exist, then the pointer is not modified. + +* `read_chunk()` takes a `chunk_read_fn` function pointer and calls it + with the appropriate initial pointer and size information. The function + is not called if the chunk does not exist. Use this method to read chunks + if you need to perform immediate parsing or if you need to execute logic + based on the size of the chunk. + +After calling these methods, call `free_chunkfile()` to clear the +`struct chunkfile` data. This will not close the memory-mapped region. +Callers are expected to own that data for the timeframe the pointers into +the region are needed. + +Examples +-------- + +These file formats use the chunk-format API, and can be used as examples +for future formats: + +* *commit-graph:* see `write_commit_graph_file()` and `parse_commit_graph()` + in `commit-graph.c` for how the chunk-format API is used to write and + parse the commit-graph file format documented in + link:technical/commit-graph-format.html[the commit-graph file format]. + +* *multi-pack-index:* see `write_midx_internal()` and `load_multi_pack_index()` + in `midx.c` for how the chunk-format API is used to write and + parse the multi-pack-index file format documented in + link:technical/pack-format.html[the multi-pack-index file format]. diff --git a/Documentation/technical/commit-graph-format.txt b/Documentation/technical/commit-graph-format.txt index b3b58880b9..87971c27dd 100644 --- a/Documentation/technical/commit-graph-format.txt +++ b/Documentation/technical/commit-graph-format.txt @@ -4,11 +4,7 @@ Git commit graph format The Git commit graph stores a list of commit OIDs and some associated metadata, including: -- The generation number of the commit. Commits with no parents have - generation number 1; commits with parents have generation number - one more than the maximum generation number of its parents. We - reserve zero as special, and can be used to mark a generation - number invalid or as "not computed". +- The generation number of the commit. - The root tree OID. @@ -65,6 +61,9 @@ CHUNK LOOKUP: the length using the next chunk position if necessary.) Each chunk ID appears at most once. + The CHUNK LOOKUP matches the table of contents from + link:technical/chunk-format.html[the chunk-based file format]. + The remaining data in the body is described one chunk at a time, and these chunks may be given in any order. Chunks are required unless otherwise specified. @@ -86,13 +85,33 @@ CHUNK DATA: position. If there are more than two parents, the second value has its most-significant bit on and the other bits store an array position into the Extra Edge List chunk. - * The next 8 bytes store the generation number of the commit and + * The next 8 bytes store the topological level (generation number v1) + of the commit and the commit time in seconds since EPOCH. The generation number uses the higher 30 bits of the first 4 bytes, while the commit time uses the 32 bits of the second 4 bytes, along with the lowest 2 bits of the lowest byte, storing the 33rd and 34th bit of the commit time. + Generation Data (ID: {'G', 'D', 'A', 'T' }) (N * 4 bytes) [Optional] + * This list of 4-byte values store corrected commit date offsets for the + commits, arranged in the same order as commit data chunk. + * If the corrected commit date offset cannot be stored within 31 bits, + the value has its most-significant bit on and the other bits store + the position of corrected commit date into the Generation Data Overflow + chunk. + * Generation Data chunk is present only when commit-graph file is written + by compatible versions of Git and in case of split commit-graph chains, + the topmost layer also has Generation Data chunk. + + Generation Data Overflow (ID: {'G', 'D', 'O', 'V' }) [Optional] + * This list of 8-byte values stores the corrected commit date offsets + for commits with corrected commit date offsets that cannot be + stored within 31 bits. + * Generation Data Overflow chunk is present only when Generation Data + chunk is present and atleast one corrected commit date offset cannot + be stored within 31 bits. + Extra Edge List (ID: {'E', 'D', 'G', 'E'}) [Optional] This list of 4-byte values store the second through nth parents for all octopus merges. The second parent value in the commit data stores diff --git a/Documentation/technical/commit-graph.txt b/Documentation/technical/commit-graph.txt index f14a7659aa..f05e7bda1a 100644 --- a/Documentation/technical/commit-graph.txt +++ b/Documentation/technical/commit-graph.txt @@ -38,14 +38,31 @@ A consumer may load the following info for a commit from the graph: Values 1-4 satisfy the requirements of parse_commit_gently(). -Define the "generation number" of a commit recursively as follows: +There are two definitions of generation number: +1. Corrected committer dates (generation number v2) +2. Topological levels (generation nummber v1) - * A commit with no parents (a root commit) has generation number one. +Define "corrected committer date" of a commit recursively as follows: - * A commit with at least one parent has generation number one more than - the largest generation number among its parents. + * A commit with no parents (a root commit) has corrected committer date + equal to its committer date. -Equivalently, the generation number of a commit A is one more than the + * A commit with at least one parent has corrected committer date equal to + the maximum of its commiter date and one more than the largest corrected + committer date among its parents. + + * As a special case, a root commit with timestamp zero has corrected commit + date of 1, to be able to distinguish it from GENERATION_NUMBER_ZERO + (that is, an uncomputed corrected commit date). + +Define the "topological level" of a commit recursively as follows: + + * A commit with no parents (a root commit) has topological level of one. + + * A commit with at least one parent has topological level one more than + the largest topological level among its parents. + +Equivalently, the topological level of a commit A is one more than the length of a longest path from A to a root commit. The recursive definition is easier to use for computation and observing the following property: @@ -60,6 +77,9 @@ is easier to use for computation and observing the following property: generation numbers, then we always expand the boundary commit with highest generation number and can easily detect the stopping condition. +The property applies to both versions of generation number, that is both +corrected committer dates and topological levels. + This property can be used to significantly reduce the time it takes to walk commits and determine topological relationships. Without generation numbers, the general heuristic is the following: @@ -67,7 +87,9 @@ numbers, the general heuristic is the following: If A and B are commits with commit time X and Y, respectively, and X < Y, then A _probably_ cannot reach B. -This heuristic is currently used whenever the computation is allowed to +In absence of corrected commit dates (for example, old versions of Git or +mixed generation graph chains), +this heuristic is currently used whenever the computation is allowed to violate topological relationships due to clock skew (such as "git log" with default order), but is not used when the topological order is required (such as merge base calculations, "git log --graph"). @@ -77,7 +99,7 @@ in the commit graph. We can treat these commits as having "infinite" generation number and walk until reaching commits with known generation number. -We use the macro GENERATION_NUMBER_INFINITY = 0xFFFFFFFF to mark commits not +We use the macro GENERATION_NUMBER_INFINITY to mark commits not in the commit-graph file. If a commit-graph file was written by a version of Git that did not compute generation numbers, then those commits will have generation number represented by the macro GENERATION_NUMBER_ZERO = 0. @@ -93,12 +115,12 @@ fully-computed generation numbers. Using strict inequality may result in walking a few extra commits, but the simplicity in dealing with commits with generation number *_INFINITY or *_ZERO is valuable. -We use the macro GENERATION_NUMBER_MAX = 0x3FFFFFFF to for commits whose -generation numbers are computed to be at least this value. We limit at -this value since it is the largest value that can be stored in the -commit-graph file using the 30 bits available to generation numbers. This -presents another case where a commit can have generation number equal to -that of a parent. +We use the macro GENERATION_NUMBER_V1_MAX = 0x3FFFFFFF for commits whose +topological levels (generation number v1) are computed to be at least +this value. We limit at this value since it is the largest value that +can be stored in the commit-graph file using the 30 bits available +to topological levels. This presents another case where a commit can +have generation number equal to that of a parent. Design Details -------------- @@ -267,6 +289,35 @@ The merge strategy values (2 for the size multiple, 64,000 for the maximum number of commits) could be extracted into config settings for full flexibility. +## Handling Mixed Generation Number Chains + +With the introduction of generation number v2 and generation data chunk, the +following scenario is possible: + +1. "New" Git writes a commit-graph with the corrected commit dates. +2. "Old" Git writes a split commit-graph on top without corrected commit dates. + +A naive approach of using the newest available generation number from +each layer would lead to violated expectations: the lower layer would +use corrected commit dates which are much larger than the topological +levels of the higher layer. For this reason, Git inspects the topmost +layer to see if the layer is missing corrected commit dates. In such a case +Git only uses topological level for generation numbers. + +When writing a new layer in split commit-graph, we write corrected commit +dates if the topmost layer has corrected commit dates written. This +guarantees that if a layer has corrected commit dates, all lower layers +must have corrected commit dates as well. + +When merging layers, we do not consider whether the merged layers had corrected +commit dates. Instead, the new layer will have corrected commit dates if the +layer below the new layer has corrected commit dates. + +While writing or merging layers, if the new layer is the only layer, it will +have corrected commit dates when written by compatible versions of Git. Thus, +rewriting split commit-graph as a single file (`--split=replace`) creates a +single layer with corrected commit dates. + ## Deleting graph-{hash} files After a new tip file is written, some `graph-{hash}` files may no longer diff --git a/Documentation/technical/hash-function-transition.txt b/Documentation/technical/hash-function-transition.txt index 6fd20ebbc2..7c1630bf83 100644 --- a/Documentation/technical/hash-function-transition.txt +++ b/Documentation/technical/hash-function-transition.txt @@ -33,16 +33,9 @@ researchers. On 23 February 2017 the SHAttered attack Git v2.13.0 and later subsequently moved to a hardened SHA-1 implementation by default, which isn't vulnerable to the SHAttered -attack. +attack, but SHA-1 is still weak. -Thus Git has in effect already migrated to a new hash that isn't SHA-1 -and doesn't share its vulnerabilities, its new hash function just -happens to produce exactly the same output for all known inputs, -except two PDFs published by the SHAttered researchers, and the new -implementation (written by those researchers) claims to detect future -cryptanalytic collision attacks. - -Regardless, it's considered prudent to move past any variant of SHA-1 +Thus it's considered prudent to move past any variant of SHA-1 to a new hash. There's no guarantee that future attacks on SHA-1 won't be published in the future, and those attacks may not have viable mitigations. @@ -57,6 +50,38 @@ SHA-1 still possesses the other properties such as fast object lookup and safe error checking, but other hash functions are equally suitable that are believed to be cryptographically secure. +Choice of Hash +-------------- +The hash to replace the hardened SHA-1 should be stronger than SHA-1 +was: we would like it to be trustworthy and useful in practice for at +least 10 years. + +Some other relevant properties: + +1. A 256-bit hash (long enough to match common security practice; not + excessively long to hurt performance and disk usage). + +2. High quality implementations should be widely available (e.g., in + OpenSSL and Apple CommonCrypto). + +3. The hash function's properties should match Git's needs (e.g. Git + requires collision and 2nd preimage resistance and does not require + length extension resistance). + +4. As a tiebreaker, the hash should be fast to compute (fortunately + many contenders are faster than SHA-1). + +There were several contenders for a successor hash to SHA-1, including +SHA-256, SHA-512/256, SHA-256x16, K12, and BLAKE2bp-256. + +In late 2018 the project picked SHA-256 as its successor hash. + +See 0ed8d8da374 (doc hash-function-transition: pick SHA-256 as +NewHash, 2018-08-04) and numerous mailing list threads at the time, +particularly the one starting at +https://lore.kernel.org/git/20180609224913.GC38834@genre.crustytoothpaste.net/ +for more information. + Goals ----- 1. The transition to SHA-256 can be done one local repository at a time. @@ -94,7 +119,7 @@ Overview -------- We introduce a new repository format extension. Repositories with this extension enabled use SHA-256 instead of SHA-1 to name their objects. -This affects both object names and object content --- both the names +This affects both object names and object content -- both the names of objects and all references to other objects within an object are switched to the new hash function. @@ -107,7 +132,7 @@ mapping to allow naming objects using either their SHA-1 and SHA-256 names interchangeably. "git cat-file" and "git hash-object" gain options to display an object -in its sha1 form and write an object given its sha1 form. This +in its SHA-1 form and write an object given its SHA-1 form. This requires all objects referenced by that object to be present in the object database so that they can be named using the appropriate name (using the bidirectional hash mapping). @@ -115,7 +140,7 @@ object database so that they can be named using the appropriate name Fetches from a SHA-1 based server convert the fetched objects into SHA-256 form and record the mapping in the bidirectional mapping table (see below for details). Pushes to a SHA-1 based server convert the -objects being pushed into sha1 form so the server does not have to be +objects being pushed into SHA-1 form so the server does not have to be aware of the hash function the client is using. Detailed Design @@ -151,38 +176,38 @@ repository extensions. Object names ~~~~~~~~~~~~ -Objects can be named by their 40 hexadecimal digit sha1-name or 64 -hexadecimal digit sha256-name, plus names derived from those (see +Objects can be named by their 40 hexadecimal digit SHA-1 name or 64 +hexadecimal digit SHA-256 name, plus names derived from those (see gitrevisions(7)). -The sha1-name of an object is the SHA-1 of the concatenation of its -type, length, a nul byte, and the object's sha1-content. This is the +The SHA-1 name of an object is the SHA-1 of the concatenation of its +type, length, a nul byte, and the object's SHA-1 content. This is the traditional <sha1> used in Git to name objects. -The sha256-name of an object is the SHA-256 of the concatenation of its -type, length, a nul byte, and the object's sha256-content. +The SHA-256 name of an object is the SHA-256 of the concatenation of its +type, length, a nul byte, and the object's SHA-256 content. Object format ~~~~~~~~~~~~~ The content as a byte sequence of a tag, commit, or tree object named -by sha1 and sha256 differ because an object named by sha256-name refers to -other objects by their sha256-names and an object named by sha1-name -refers to other objects by their sha1-names. +by SHA-1 and SHA-256 differ because an object named by SHA-256 name refers to +other objects by their SHA-256 names and an object named by SHA-1 name +refers to other objects by their SHA-1 names. -The sha256-content of an object is the same as its sha1-content, except -that objects referenced by the object are named using their sha256-names -instead of sha1-names. Because a blob object does not refer to any -other object, its sha1-content and sha256-content are the same. +The SHA-256 content of an object is the same as its SHA-1 content, except +that objects referenced by the object are named using their SHA-256 names +instead of SHA-1 names. Because a blob object does not refer to any +other object, its SHA-1 content and SHA-256 content are the same. -The format allows round-trip conversion between sha256-content and -sha1-content. +The format allows round-trip conversion between SHA-256 content and +SHA-1 content. Object storage ~~~~~~~~~~~~~~ Loose objects use zlib compression and packed objects use the packed format described in Documentation/technical/pack-format.txt, just like -today. The content that is compressed and stored uses sha256-content -instead of sha1-content. +today. The content that is compressed and stored uses SHA-256 content +instead of SHA-1 content. Pack index ~~~~~~~~~~ @@ -191,21 +216,21 @@ hash functions. They have the following format (all integers are in network byte order): - A header appears at the beginning and consists of the following: - - The 4-byte pack index signature: '\377t0c' - - 4-byte version number: 3 - - 4-byte length of the header section, including the signature and + * The 4-byte pack index signature: '\377t0c' + * 4-byte version number: 3 + * 4-byte length of the header section, including the signature and version number - - 4-byte number of objects contained in the pack - - 4-byte number of object formats in this pack index: 2 - - For each object format: - - 4-byte format identifier (e.g., 'sha1' for SHA-1) - - 4-byte length in bytes of shortened object names. This is the + * 4-byte number of objects contained in the pack + * 4-byte number of object formats in this pack index: 2 + * For each object format: + ** 4-byte format identifier (e.g., 'sha1' for SHA-1) + ** 4-byte length in bytes of shortened object names. This is the shortest possible length needed to make names in the shortened object name table unambiguous. - - 4-byte integer, recording where tables relating to this format + ** 4-byte integer, recording where tables relating to this format are stored in this index file, as an offset from the beginning. - - 4-byte offset to the trailer from the beginning of this file. - - Zero or more additional key/value pairs (4-byte key, 4-byte + * 4-byte offset to the trailer from the beginning of this file. + * Zero or more additional key/value pairs (4-byte key, 4-byte value). Only one key is supported: 'PSRC'. See the "Loose objects and unreachable objects" section for supported values and how this is used. All other keys are reserved. Readers must ignore @@ -213,37 +238,36 @@ network byte order): - Zero or more NUL bytes. This can optionally be used to improve the alignment of the full object name table below. - Tables for the first object format: - - A sorted table of shortened object names. These are prefixes of + * A sorted table of shortened object names. These are prefixes of the names of all objects in this pack file, packed together without offset values to reduce the cache footprint of the binary search for a specific object name. - - A table of full object names in pack order. This allows resolving + * A table of full object names in pack order. This allows resolving a reference to "the nth object in the pack file" (from a reachability bitmap or from the next table of another object format) to its object name. - - A table of 4-byte values mapping object name order to pack order. + * A table of 4-byte values mapping object name order to pack order. For an object in the table of sorted shortened object names, the value at the corresponding index in this table is the index in the previous table for that same object. - This can be used to look up the object in reachability bitmaps or to look up its name in another object format. - - A table of 4-byte CRC32 values of the packed object data, in the + * A table of 4-byte CRC32 values of the packed object data, in the order that the objects appear in the pack file. This is to allow compressed data to be copied directly from pack to pack during repacking without undetected data corruption. - - A table of 4-byte offset values. For an object in the table of + * A table of 4-byte offset values. For an object in the table of sorted shortened object names, the value at the corresponding index in this table indicates where that object can be found in the pack file. These are usually 31-bit pack file offsets, but large offsets are encoded as an index into the next table with the most significant bit set. - - A table of 8-byte offset entries (empty for pack files less than + * A table of 8-byte offset entries (empty for pack files less than 2 GiB). Pack files are organized with heavily used objects toward the front, so most object references should not need to refer to this table. @@ -252,10 +276,10 @@ network byte order): up to and not including the table of CRC32 values. - Zero or more NUL bytes. - The trailer consists of the following: - - A copy of the 20-byte SHA-256 checksum at the end of the + * A copy of the 20-byte SHA-256 checksum at the end of the corresponding packfile. - - 20-byte SHA-256 checksum of all of the above. + * 20-byte SHA-256 checksum of all of the above. Loose object index ~~~~~~~~~~~~~~~~~~ @@ -288,18 +312,18 @@ To remove entries (e.g. in "git pack-refs" or "git-prune"): Translation table ~~~~~~~~~~~~~~~~~ -The index files support a bidirectional mapping between sha1-names -and sha256-names. The lookup proceeds similarly to ordinary object -lookups. For example, to convert a sha1-name to a sha256-name: +The index files support a bidirectional mapping between SHA-1 names +and SHA-256 names. The lookup proceeds similarly to ordinary object +lookups. For example, to convert a SHA-1 name to a SHA-256 name: 1. Look for the object in idx files. If a match is present in the - idx's sorted list of truncated sha1-names, then: - a. Read the corresponding entry in the sha1-name order to pack + idx's sorted list of truncated SHA-1 names, then: + a. Read the corresponding entry in the SHA-1 name order to pack name order mapping. - b. Read the corresponding entry in the full sha1-name table to + b. Read the corresponding entry in the full SHA-1 name table to verify we found the right object. If it is, then - c. Read the corresponding entry in the full sha256-name table. - That is the object's sha256-name. + c. Read the corresponding entry in the full SHA-256 name table. + That is the object's SHA-256 name. 2. Check for a loose object. Read lines from loose-object-idx until we find a match. @@ -313,10 +337,10 @@ Since all operations that make new objects (e.g., "git commit") add the new objects to the corresponding index, this mapping is possible for all objects in the object store. -Reading an object's sha1-content -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The sha1-content of an object can be read by converting all sha256-names -its sha256-content references to sha1-names using the translation table. +Reading an object's SHA-1 content +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The SHA-1 content of an object can be read by converting all SHA-256 names +of its SHA-256 content references to SHA-1 names using the translation table. Fetch ~~~~~ @@ -339,7 +363,7 @@ the following steps: 1. index-pack: inflate each object in the packfile and compute its SHA-1. Objects can contain deltas in OBJ_REF_DELTA format against objects the client has locally. These objects can be looked up - using the translation table and their sha1-content read as + using the translation table and their SHA-1 content read as described above to resolve the deltas. 2. topological sort: starting at the "want"s from the negotiation phase, walk through objects in the pack and emit a list of them, @@ -348,12 +372,12 @@ the following steps: (This list only contains objects reachable from the "wants". If the pack from the server contained additional extraneous objects, then they will be discarded.) -3. convert to sha256: open a new (sha256) packfile. Read the topologically +3. convert to SHA-256: open a new SHA-256 packfile. Read the topologically sorted list just generated. For each object, inflate its - sha1-content, convert to sha256-content, and write it to the sha256 - pack. Record the new sha1<->sha256 mapping entry for use in the idx. + SHA-1 content, convert to SHA-256 content, and write it to the SHA-256 + pack. Record the new SHA-1<-->SHA-256 mapping entry for use in the idx. 4. sort: reorder entries in the new pack to match the order of objects - in the pack the server generated and include blobs. Write a sha256 idx + in the pack the server generated and include blobs. Write a SHA-256 idx file 5. clean up: remove the SHA-1 based pack file, index, and topologically sorted list obtained from the server in steps 1 @@ -378,19 +402,20 @@ experimenting to get this to perform well. Push ~~~~ Push is simpler than fetch because the objects referenced by the -pushed objects are already in the translation table. The sha1-content +pushed objects are already in the translation table. The SHA-1 content of each object being pushed can be read as described in the "Reading -an object's sha1-content" section to generate the pack written by git +an object's SHA-1 content" section to generate the pack written by git send-pack. Signed Commits ~~~~~~~~~~~~~~ We add a new field "gpgsig-sha256" to the commit object format to allow signing commits without relying on SHA-1. It is similar to the -existing "gpgsig" field. Its signed payload is the sha256-content of the +existing "gpgsig" field. Its signed payload is the SHA-256 content of the commit object with any "gpgsig" and "gpgsig-sha256" fields removed. This means commits can be signed + 1. using SHA-1 only, as in existing signed commit objects 2. using both SHA-1 and SHA-256, by using both gpgsig-sha256 and gpgsig fields. @@ -404,10 +429,11 @@ Signed Tags ~~~~~~~~~~~ We add a new field "gpgsig-sha256" to the tag object format to allow signing tags without relying on SHA-1. Its signed payload is the -sha256-content of the tag with its gpgsig-sha256 field and "-----BEGIN PGP +SHA-256 content of the tag with its gpgsig-sha256 field and "-----BEGIN PGP SIGNATURE-----" delimited in-body signature removed. This means tags can be signed + 1. using SHA-1 only, as in existing signed tag objects 2. using both SHA-1 and SHA-256, by using gpgsig-sha256 and an in-body signature. @@ -415,11 +441,11 @@ This means tags can be signed Mergetag embedding ~~~~~~~~~~~~~~~~~~ -The mergetag field in the sha1-content of a commit contains the -sha1-content of a tag that was merged by that commit. +The mergetag field in the SHA-1 content of a commit contains the +SHA-1 content of a tag that was merged by that commit. -The mergetag field in the sha256-content of the same commit contains the -sha256-content of the same tag. +The mergetag field in the SHA-256 content of the same commit contains the +SHA-256 content of the same tag. Submodules ~~~~~~~~~~ @@ -494,7 +520,7 @@ Caveats ------- Invalid objects ~~~~~~~~~~~~~~~ -The conversion from sha1-content to sha256-content retains any +The conversion from SHA-1 content to SHA-256 content retains any brokenness in the original object (e.g., tree entry modes encoded with leading 0, tree objects whose paths are not sorted correctly, and commit objects without an author or committer). This is a deliberate @@ -513,15 +539,15 @@ allow lifting this restriction. Alternates ~~~~~~~~~~ -For the same reason, a sha256 repository cannot borrow objects from a -sha1 repository using objects/info/alternates or +For the same reason, a SHA-256 repository cannot borrow objects from a +SHA-1 repository using objects/info/alternates or $GIT_ALTERNATE_OBJECT_REPOSITORIES. git notes ~~~~~~~~~ -The "git notes" tool annotates objects using their sha1-name as key. +The "git notes" tool annotates objects using their SHA-1 name as key. This design does not describe a way to migrate notes trees to use -sha256-names. That migration is expected to happen separately (for +SHA-256 names. That migration is expected to happen separately (for example using a file at the root of the notes tree to describe which hash it uses). @@ -555,7 +581,7 @@ unclear: Git 2.12 -Does this mean Git v2.12.0 is the commit with sha1-name +Does this mean Git v2.12.0 is the commit with SHA-1 name e7e07d5a4fcc2a203d9873968ad3e6bd4d7419d7 or the commit with new-40-digit-hash-name e7e07d5a4fcc2a203d9873968ad3e6bd4d7419d7? @@ -598,44 +624,12 @@ The user can also explicitly specify which format to use for a particular revision specifier and for output, overriding the mode. For example: -git --output-format=sha1 log abac87a^{sha1}..f787cac^{sha256} - -Choice of Hash --------------- -In early 2005, around the time that Git was written, Xiaoyun Wang, -Yiqun Lisa Yin, and Hongbo Yu announced an attack finding SHA-1 -collisions in 2^69 operations. In August they published details. -Luckily, no practical demonstrations of a collision in full SHA-1 were -published until 10 years later, in 2017. - -Git v2.13.0 and later subsequently moved to a hardened SHA-1 -implementation by default that mitigates the SHAttered attack, but -SHA-1 is still believed to be weak. - -The hash to replace this hardened SHA-1 should be stronger than SHA-1 -was: we would like it to be trustworthy and useful in practice for at -least 10 years. - -Some other relevant properties: - -1. A 256-bit hash (long enough to match common security practice; not - excessively long to hurt performance and disk usage). - -2. High quality implementations should be widely available (e.g., in - OpenSSL and Apple CommonCrypto). - -3. The hash function's properties should match Git's needs (e.g. Git - requires collision and 2nd preimage resistance and does not require - length extension resistance). - -4. As a tiebreaker, the hash should be fast to compute (fortunately - many contenders are faster than SHA-1). - -We choose SHA-256. + git --output-format=sha1 log abac87a^{sha1}..f787cac^{sha256} Transition plan --------------- Some initial steps can be implemented independently of one another: + - adding a hash function API (vtable) - teaching fsck to tolerate the gpgsig-sha256 field - excluding gpgsig-* from the fields copied by "git commit --amend" @@ -647,9 +641,9 @@ Some initial steps can be implemented independently of one another: - introducing index v3 - adding support for the PSRC field and safer object pruning - The first user-visible change is the introduction of the objectFormat extension (without compatObjectFormat). This requires: + - teaching fsck about this mode of operation - using the hash function API (vtable) when computing object names - signing objects and verifying signatures @@ -657,6 +651,7 @@ extension (without compatObjectFormat). This requires: repository Next comes introduction of compatObjectFormat: + - implementing the loose-object-idx - translating object names between object formats - translating object content between object formats @@ -669,10 +664,11 @@ Next comes introduction of compatObjectFormat: "Object names on the command line" above) The next step is supporting fetches and pushes to SHA-1 repositories: + - allow pushes to a repository using the compat format - generate a topologically sorted list of the SHA-1 names of fetched objects -- convert the fetched packfile to sha256 format and generate an idx +- convert the fetched packfile to SHA-256 format and generate an idx file - re-sort to match the order of objects in the fetched packfile @@ -734,6 +730,7 @@ Using hash functions in parallel Objects newly created would be addressed by the new hash, but inside such an object (e.g. commit) it is still possible to address objects using the old hash function. + * You cannot trust its history (needed for bisectability) in the future without further work * Maintenance burden as the number of supported hash functions grows @@ -743,36 +740,38 @@ using the old hash function. Signed objects with multiple hashes ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Instead of introducing the gpgsig-sha256 field in commit and tag objects -for sha256-content based signatures, an earlier version of this design -added "hash sha256 <sha256-name>" fields to strengthen the existing -sha1-content based signatures. +for SHA-256 content based signatures, an earlier version of this design +added "hash sha256 <SHA-256 name>" fields to strengthen the existing +SHA-1 content based signatures. In other words, a single signature was used to attest to the object content using both hash functions. This had some advantages: + * Using one signature instead of two speeds up the signing process. * Having one signed payload with both hashes allows the signer to - attest to the sha1-name and sha256-name referring to the same object. + attest to the SHA-1 name and SHA-256 name referring to the same object. * All users consume the same signature. Broken signatures are likely to be detected quickly using current versions of git. However, it also came with disadvantages: -* Verifying a signed object requires access to the sha1-names of all + +* Verifying a signed object requires access to the SHA-1 names of all objects it references, even after the transition is complete and translation table is no longer needed for anything else. To support - this, the design added fields such as "hash sha1 tree <sha1-name>" - and "hash sha1 parent <sha1-name>" to the sha256-content of a signed + this, the design added fields such as "hash sha1 tree <SHA-1 name>" + and "hash sha1 parent <SHA-1 name>" to the SHA-256 content of a signed commit, complicating the conversion process. -* Allowing signed objects without a sha1 (for after the transition is +* Allowing signed objects without a SHA-1 (for after the transition is complete) complicated the design further, requiring a "nohash sha1" - field to suppress including "hash sha1" fields in the sha256-content + field to suppress including "hash sha1" fields in the SHA-256 content and signed payload. Lazily populated translation table ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Some of the work of building the translation table could be deferred to push time, but that would significantly complicate and slow down pushes. -Calculating the sha1-name at object creation time at the same time it is -being streamed to disk and having its sha256-name calculated should be +Calculating the SHA-1 name at object creation time at the same time it is +being streamed to disk and having its SHA-256 name calculated should be an acceptable cost. Document History @@ -782,18 +781,19 @@ Document History bmwill@google.com, jonathantanmy@google.com, jrnieder@gmail.com, sbeller@google.com -Initial version sent to -http://lore.kernel.org/git/20170304011251.GA26789@aiede.mtv.corp.google.com +* Initial version sent to https://lore.kernel.org/git/20170304011251.GA26789@aiede.mtv.corp.google.com 2017-03-03 jrnieder@gmail.com Incorporated suggestions from jonathantanmy and sbeller: -* describe purpose of signed objects with each hash type -* redefine signed object verification using object content under the + +* Describe purpose of signed objects with each hash type +* Redefine signed object verification using object content under the first hash function 2017-03-06 jrnieder@gmail.com + * Use SHA3-256 instead of SHA2 (thanks, Linus and brian m. carlson).[1][2] -* Make sha3-based signatures a separate field, avoiding the need for +* Make SHA3-based signatures a separate field, avoiding the need for "hash" and "nohash" fields (thanks to peff[3]). * Add a sorting phase to fetch (thanks to Junio for noticing the need for this). @@ -805,23 +805,26 @@ Incorporated suggestions from jonathantanmy and sbeller: especially Junio). 2017-09-27 jrnieder@gmail.com, sbeller@google.com -* use placeholder NewHash instead of SHA3-256 -* describe criteria for picking a hash function. -* include a transition plan (thanks especially to Brandon Williams + +* Use placeholder NewHash instead of SHA3-256 +* Describe criteria for picking a hash function. +* Include a transition plan (thanks especially to Brandon Williams for fleshing these ideas out) -* define the translation table (thanks, Shawn Pearce[5], Jonathan +* Define the translation table (thanks, Shawn Pearce[5], Jonathan Tan, and Masaya Suzuki) -* avoid loose object overhead by packing more aggressively in +* Avoid loose object overhead by packing more aggressively in "git gc --auto" Later history: - See the history of this file in git.git for the history of subsequent - edits. This document history is no longer being maintained as it - would now be superfluous to the commit log +* See the history of this file in git.git for the history of subsequent + edits. This document history is no longer being maintained as it + would now be superfluous to the commit log + +References: -[1] http://lore.kernel.org/git/CA+55aFzJtejiCjV0e43+9oR3QuJK2PiFiLQemytoLpyJWe6P9w@mail.gmail.com/ -[2] http://lore.kernel.org/git/CA+55aFz+gkAsDZ24zmePQuEs1XPS9BP_s8O7Q4wQ7LV7X5-oDA@mail.gmail.com/ -[3] http://lore.kernel.org/git/20170306084353.nrns455dvkdsfgo5@sigill.intra.peff.net/ -[4] http://lore.kernel.org/git/20170304224936.rqqtkdvfjgyezsht@genre.crustytoothpaste.net -[5] https://lore.kernel.org/git/CAJo=hJtoX9=AyLHHpUJS7fueV9ciZ_MNpnEPHUz8Whui6g9F0A@mail.gmail.com/ + [1] https://lore.kernel.org/git/CA+55aFzJtejiCjV0e43+9oR3QuJK2PiFiLQemytoLpyJWe6P9w@mail.gmail.com/ + [2] https://lore.kernel.org/git/CA+55aFz+gkAsDZ24zmePQuEs1XPS9BP_s8O7Q4wQ7LV7X5-oDA@mail.gmail.com/ + [3] https://lore.kernel.org/git/20170306084353.nrns455dvkdsfgo5@sigill.intra.peff.net/ + [4] https://lore.kernel.org/git/20170304224936.rqqtkdvfjgyezsht@genre.crustytoothpaste.net + [5] https://lore.kernel.org/git/CAJo=hJtoX9=AyLHHpUJS7fueV9ciZ_MNpnEPHUz8Whui6g9F0A@mail.gmail.com/ diff --git a/Documentation/technical/index-format.txt b/Documentation/technical/index-format.txt index 69edf46c03..65da0daaa5 100644 --- a/Documentation/technical/index-format.txt +++ b/Documentation/technical/index-format.txt @@ -26,7 +26,7 @@ Git index format Extensions are identified by signature. Optional extensions can be ignored if Git does not understand them. - Git currently supports cached tree and resolve undo extensions. + Git currently supports cache tree and resolve undo extensions. 4-byte extension signature. If the first byte is 'A'..'Z' the extension is optional and can be ignored. @@ -44,6 +44,13 @@ Git index format localization, no special casing of directory separator '/'). Entries with the same name are sorted by their stage field. + An index entry typically represents a file. However, if sparse-checkout + is enabled in cone mode (`core.sparseCheckoutCone` is enabled) and the + `extensions.sparseIndex` extension is enabled, then the index may + contain entries for directories outside of the sparse-checkout definition. + These entries have mode `040000`, include the `SKIP_WORKTREE` bit, and + the path ends in a directory separator. + 32-bit ctime seconds, the last time a file's metadata changed this is stat(2) data @@ -136,14 +143,35 @@ Git index format == Extensions -=== Cached tree - - Cached tree extension contains pre-computed hashes for trees that can - be derived from the index. It helps speed up tree object generation - from index for a new commit. - - When a path is updated in index, the path must be invalidated and - removed from tree cache. +=== Cache tree + + Since the index does not record entries for directories, the cache + entries cannot describe tree objects that already exist in the object + database for regions of the index that are unchanged from an existing + commit. The cache tree extension stores a recursive tree structure that + describes the trees that already exist and completely match sections of + the cache entries. This speeds up tree object generation from the index + for a new commit by only computing the trees that are "new" to that + commit. It also assists when comparing the index to another tree, such + as `HEAD^{tree}`, since sections of the index can be skipped when a tree + comparison demonstrates equality. + + The recursive tree structure uses nodes that store a number of cache + entries, a list of subnodes, and an object ID (OID). The OID references + the existing tree for that node, if it is known to exist. The subnodes + correspond to subdirectories that themselves have cache tree nodes. The + number of cache entries corresponds to the number of cache entries in + the index that describe paths within that tree's directory. + + The extension tracks the full directory structure in the cache tree + extension, but this is generally smaller than the full cache entry list. + + When a path is updated in index, Git invalidates all nodes of the + recursive cache tree corresponding to the parent directories of that + path. We store these tree nodes as being "invalid" by using "-1" as the + number of cache entries. Invalid nodes still store a span of index + entries, allowing Git to focus its efforts when reconstructing a full + cache tree. The signature for this extension is { 'T', 'R', 'E', 'E' }. @@ -174,7 +202,8 @@ Git index format first entry represents the root level of the repository, followed by the first subtree--let's call this A--of the root level (with its name relative to the root level), followed by the first subtree of A (with - its name relative to A), ... + its name relative to A), and so on. The specified number of subtrees + indicates when the current level of the recursive stack is complete. === Resolve undo @@ -251,14 +280,14 @@ Git index format - Stat data of $GIT_DIR/info/exclude. See "Index entry" section from ctime field until "file size". - - Stat data of core.excludesfile + - Stat data of core.excludesFile - 32-bit dir_flags (see struct dir_struct) - Hash of $GIT_DIR/info/exclude. A null hash means the file does not exist. - - Hash of core.excludesfile. A null hash means the file does + - Hash of core.excludesFile. A null hash means the file does not exist. - NUL-terminated string of per-dir exclude file name. This usually @@ -363,3 +392,15 @@ The remaining data of each directory block is grouped by type: in this block of entries. - 32-bit count of cache entries in this block + +== Sparse Directory Entries + + When using sparse-checkout in cone mode, some entire directories within + the index can be summarized by pointing to a tree object instead of the + entire expanded list of paths within that tree. An index containing such + entries is a "sparse index". Index format versions 4 and less were not + implemented with such entries in mind. Thus, for these versions, an + index containing sparse directory entries will include this extension + with signature { 's', 'd', 'i', 'r' }. Like the split-index extension, + tools should avoid interacting with a sparse index unless they understand + this extension. diff --git a/Documentation/technical/multi-pack-index.txt b/Documentation/technical/multi-pack-index.txt index e8e377a59f..fb688976c4 100644 --- a/Documentation/technical/multi-pack-index.txt +++ b/Documentation/technical/multi-pack-index.txt @@ -43,8 +43,9 @@ Design Details a change in format. - The MIDX keeps only one record per object ID. If an object appears - in multiple packfiles, then the MIDX selects the copy in the most- - recently modified packfile. + in multiple packfiles, then the MIDX selects the copy in the + preferred packfile, otherwise selecting from the most-recently + modified packfile. - If there exist packfiles in the pack directory not registered in the MIDX, then those packfiles are loaded into the `packed_git` diff --git a/Documentation/technical/pack-format.txt b/Documentation/technical/pack-format.txt index 96d2fc589f..8d2f42f29e 100644 --- a/Documentation/technical/pack-format.txt +++ b/Documentation/technical/pack-format.txt @@ -274,6 +274,26 @@ Pack file entry: <+ Index checksum of all of the above. +== pack-*.rev files have the format: + + - A 4-byte magic number '0x52494458' ('RIDX'). + + - A 4-byte version identifier (= 1). + + - A 4-byte hash function identifier (= 1 for SHA-1, 2 for SHA-256). + + - A table of index positions (one per packed object, num_objects in + total, each a 4-byte unsigned integer in network order), sorted by + their corresponding offsets in the packfile. + + - A trailer, containing a: + + checksum of the corresponding packfile, and + + a checksum of all of the above. + +All 4-byte numbers are in network order. + == multi-pack-index (MIDX) files have the following format: The multi-pack-index files refer to multiple pack-files and loose objects. @@ -316,6 +336,9 @@ CHUNK LOOKUP: (Chunks are provided in file-order, so you can infer the length using the next chunk position if necessary.) + The CHUNK LOOKUP matches the table of contents from + link:technical/chunk-format.html[the chunk-based file format]. + The remaining data in the body is described one chunk at a time, and these chunks may be given in any order. Chunks are required unless otherwise specified. @@ -356,3 +379,86 @@ CHUNK DATA: TRAILER: Index checksum of the above contents. + +== multi-pack-index reverse indexes + +Similar to the pack-based reverse index, the multi-pack index can also +be used to generate a reverse index. + +Instead of mapping between offset, pack-, and index position, this +reverse index maps between an object's position within the MIDX, and +that object's position within a pseudo-pack that the MIDX describes +(i.e., the ith entry of the multi-pack reverse index holds the MIDX +position of ith object in pseudo-pack order). + +To clarify the difference between these orderings, consider a multi-pack +reachability bitmap (which does not yet exist, but is what we are +building towards here). Each bit needs to correspond to an object in the +MIDX, and so we need an efficient mapping from bit position to MIDX +position. + +One solution is to let bits occupy the same position in the oid-sorted +index stored by the MIDX. But because oids are effectively random, their +resulting reachability bitmaps would have no locality, and thus compress +poorly. (This is the reason that single-pack bitmaps use the pack +ordering, and not the .idx ordering, for the same purpose.) + +So we'd like to define an ordering for the whole MIDX based around +pack ordering, which has far better locality (and thus compresses more +efficiently). We can think of a pseudo-pack created by the concatenation +of all of the packs in the MIDX. E.g., if we had a MIDX with three packs +(a, b, c), with 10, 15, and 20 objects respectively, we can imagine an +ordering of the objects like: + + |a,0|a,1|...|a,9|b,0|b,1|...|b,14|c,0|c,1|...|c,19| + +where the ordering of the packs is defined by the MIDX's pack list, +and then the ordering of objects within each pack is the same as the +order in the actual packfile. + +Given the list of packs and their counts of objects, you can +naïvely reconstruct that pseudo-pack ordering (e.g., the object at +position 27 must be (c,1) because packs "a" and "b" consumed 25 of the +slots). But there's a catch. Objects may be duplicated between packs, in +which case the MIDX only stores one pointer to the object (and thus we'd +want only one slot in the bitmap). + +Callers could handle duplicates themselves by reading objects in order +of their bit-position, but that's linear in the number of objects, and +much too expensive for ordinary bitmap lookups. Building a reverse index +solves this, since it is the logical inverse of the index, and that +index has already removed duplicates. But, building a reverse index on +the fly can be expensive. Since we already have an on-disk format for +pack-based reverse indexes, let's reuse it for the MIDX's pseudo-pack, +too. + +Objects from the MIDX are ordered as follows to string together the +pseudo-pack. Let `pack(o)` return the pack from which `o` was selected +by the MIDX, and define an ordering of packs based on their numeric ID +(as stored by the MIDX). Let `offset(o)` return the object offset of `o` +within `pack(o)`. Then, compare `o1` and `o2` as follows: + + - If one of `pack(o1)` and `pack(o2)` is preferred and the other + is not, then the preferred one sorts first. ++ +(This is a detail that allows the MIDX bitmap to determine which +pack should be used by the pack-reuse mechanism, since it can ask +the MIDX for the pack containing the object at bit position 0). + + - If `pack(o1) ≠ pack(o2)`, then sort the two objects in descending + order based on the pack ID. + + - Otherwise, `pack(o1) = pack(o2)`, and the objects are sorted in + pack-order (i.e., `o1` sorts ahead of `o2` exactly when `offset(o1) + < offset(o2)`). + +In short, a MIDX's pseudo-pack is the de-duplicated concatenation of +objects in packs stored by the MIDX, laid out in pack order, and the +packs arranged in MIDX order (with the preferred pack coming first). + +Finally, note that the MIDX's reverse index is not stored as a chunk in +the multi-pack-index itself. This is done because the reverse index +includes the checksum of the pack or MIDX to which it belongs, which +makes it impossible to write in the MIDX. To avoid races when rewriting +the MIDX, a MIDX reverse index includes the MIDX's checksum in its +filename (e.g., `multi-pack-index-xyz.rev`). diff --git a/Documentation/technical/parallel-checkout.txt b/Documentation/technical/parallel-checkout.txt new file mode 100644 index 0000000000..e790258a1a --- /dev/null +++ b/Documentation/technical/parallel-checkout.txt @@ -0,0 +1,270 @@ +Parallel Checkout Design Notes +============================== + +The "Parallel Checkout" feature attempts to use multiple processes to +parallelize the work of uncompressing the blobs, applying in-core +filters, and writing the resulting contents to the working tree during a +checkout operation. It can be used by all checkout-related commands, +such as `clone`, `checkout`, `reset`, `sparse-checkout`, and others. + +These commands share the following basic structure: + +* Step 1: Read the current index file into memory. + +* Step 2: Modify the in-memory index based upon the command, and + temporarily mark all cache entries that need to be updated. + +* Step 3: Populate the working tree to match the new candidate index. + This includes iterating over all of the to-be-updated cache entries + and delete, create, or overwrite the associated files in the working + tree. + +* Step 4: Write the new index to disk. + +Step 3 is the focus of the "parallel checkout" effort described here. + +Sequential Implementation +------------------------- + +For the purposes of discussion here, the current sequential +implementation of Step 3 is divided in 3 parts, each one implemented in +its own function: + +* Step 3a: `unpack-trees.c:check_updates()` contains a series of + sequential loops iterating over the `cache_entry`'s array. The main + loop in this function calls the Step 3b function for each of the + to-be-updated entries. + +* Step 3b: `entry.c:checkout_entry()` examines the existing working tree + for file conflicts, collisions, and unsaved changes. It removes files + and creates leading directories as necessary. It calls the Step 3c + function for each entry to be written. + +* Step 3c: `entry.c:write_entry()` loads the blob into memory, smudges + it if necessary, creates the file in the working tree, writes the + smudged contents, calls `fstat()` or `lstat()`, and updates the + associated `cache_entry` struct with the stat information gathered. + +It wouldn't be safe to perform Step 3b in parallel, as there could be +race conditions between file creations and removals. Instead, the +parallel checkout framework lets the sequential code handle Step 3b, +and uses parallel workers to replace the sequential +`entry.c:write_entry()` calls from Step 3c. + +Rejected Multi-Threaded Solution +-------------------------------- + +The most "straightforward" implementation would be to spread the set of +to-be-updated cache entries across multiple threads. But due to the +thread-unsafe functions in the ODB code, we would have to use locks to +coordinate the parallel operation. An early prototype of this solution +showed that the multi-threaded checkout would bring performance +improvements over the sequential code, but there was still too much lock +contention. A `perf` profiling indicated that around 20% of the runtime +during a local Linux clone (on an SSD) was spent in locking functions. +For this reason this approach was rejected in favor of using multiple +child processes, which led to a better performance. + +Multi-Process Solution +---------------------- + +Parallel checkout alters the aforementioned Step 3 to use multiple +`checkout--worker` background processes to distribute the work. The +long-running worker processes are controlled by the foreground Git +command using the existing run-command API. + +Overview +~~~~~~~~ + +Step 3b is only slightly altered; for each entry to be checked out, the +main process performs the following steps: + +* M1: Check whether there is any untracked or unclean file in the + working tree which would be overwritten by this entry, and decide + whether to proceed (removing the file(s)) or not. + +* M2: Create the leading directories. + +* M3: Load the conversion attributes for the entry's path. + +* M4: Check, based on the entry's type and conversion attributes, + whether the entry is eligible for parallel checkout (more on this + later). If it is eligible, enqueue the entry and the loaded + attributes to later write the entry in parallel. If not, write the + entry right away, using the default sequential code. + +Note: we save the conversion attributes associated with each entry +because the workers don't have access to the main process' index state, +so they can't load the attributes by themselves (and the attributes are +needed to properly smudge the entry). Additionally, this has a positive +impact on performance as (1) we don't need to load the attributes twice +and (2) the attributes machinery is optimized to handle paths in +sequential order. + +After all entries have passed through the above steps, the main process +checks if the number of enqueued entries is sufficient to spread among +the workers. If not, it just writes them sequentially. Otherwise, it +spawns the workers and distributes the queued entries uniformly in +continuous chunks. This aims to minimize the chances of two workers +writing to the same directory simultaneously, which could increase lock +contention in the kernel. + +Then, for each assigned item, each worker: + +* W1: Checks if there is any non-directory file in the leading part of + the entry's path or if there already exists a file at the entry' path. + If so, mark the entry with `PC_ITEM_COLLIDED` and skip it (more on + this later). + +* W2: Creates the file (with O_CREAT and O_EXCL). + +* W3: Loads the blob into memory (inflating and delta reconstructing + it). + +* W4: Applies any required in-process filter, like end-of-line + conversion and re-encoding. + +* W5: Writes the result to the file descriptor opened at W2. + +* W6: Calls `fstat()` or lstat()` on the just-written path, and sends + the result back to the main process, together with the end status of + the operation and the item's identification number. + +Note that, when possible, steps W3 to W5 are delegated to the streaming +machinery, removing the need to keep the entire blob in memory. + +If the worker fails to read the blob or to write it to the working tree, +it removes the created file to avoid leaving empty files behind. This is +the *only* time a worker is allowed to remove a file. + +As mentioned earlier, it is the responsibility of the main process to +remove any file that blocks the checkout operation (or abort if the +removal(s) would cause data loss and the user didn't ask to `--force`). +This is crucial to avoid race conditions and also to properly detect +path collisions at Step W1. + +After the workers finish writing the items and sending back the required +information, the main process handles the results in two steps: + +- First, it updates the in-memory index with the `lstat()` information + sent by the workers. (This must be done first as this information + might me required in the following step.) + +- Then it writes the items which collided on disk (i.e. items marked + with `PC_ITEM_COLLIDED`). More on this below. + +Path Collisions +--------------- + +Path collisions happen when two different paths correspond to the same +entry in the file system. E.g. the paths 'a' and 'A' would collide in a +case-insensitive file system. + +The sequential checkout deals with collisions in the same way that it +deals with files that were already present in the working tree before +checkout. Basically, it checks if the path that it wants to write +already exists on disk, makes sure the existing file doesn't have +unsaved data, and then overwrites it. (To be more pedantic: it deletes +the existing file and creates the new one.) So, if there are multiple +colliding files to be checked out, the sequential code will write each +one of them but only the last will actually survive on disk. + +Parallel checkout aims to reproduce the same behavior. However, we +cannot let the workers racily write to the same file on disk. Instead, +the workers detect when the entry that they want to check out would +collide with an existing file, and mark it with `PC_ITEM_COLLIDED`. +Later, the main process can sequentially feed these entries back to +`checkout_entry()` without the risk of race conditions. On clone, this +also has the effect of marking the colliding entries to later emit a +warning for the user, like the classic sequential checkout does. + +The workers are able to detect both collisions among the entries being +concurrently written and collisions between a parallel-eligible entry +and an ineligible entry. The general idea for collision detection is +quite straightforward: for each parallel-eligible entry, the main +process must remove all files that prevent this entry from being written +(before enqueueing it). This includes any non-directory file in the +leading path of the entry. Later, when a worker gets assigned the entry, +it looks again for the non-directories files and for an already existing +file at the entry's path. If any of these checks finds something, the +worker knows that there was a path collision. + +Because parallel checkout can distinguish path collisions from the case +where the file was already present in the working tree before checkout, +we could alternatively choose to skip the checkout of colliding entries. +However, each entry that doesn't get written would have NULL `lstat()` +fields on the index. This could cause performance penalties for +subsequent commands that need to refresh the index, as they would have +to go to the file system to see if the entry is dirty. Thus, if we have +N entries in a colliding group and we decide to write and `lstat()` only +one of them, every subsequent `git-status` will have to read, convert, +and hash the written file N - 1 times. By checking out all colliding +entries (like the sequential code does), we only pay the overhead once, +during checkout. + +Eligible Entries for Parallel Checkout +-------------------------------------- + +As previously mentioned, not all entries passed to `checkout_entry()` +will be considered eligible for parallel checkout. More specifically, we +exclude: + +- Symbolic links; to avoid race conditions that, in combination with + path collisions, could cause workers to write files at the wrong + place. For example, if we were to concurrently check out a symlink + 'a' -> 'b' and a regular file 'A/f' in a case-insensitive file system, + we could potentially end up writing the file 'A/f' at 'a/f', due to a + race condition. + +- Regular files that require external filters (either "one shot" filters + or long-running process filters). These filters are black-boxes to Git + and may have their own internal locking or non-concurrent assumptions. + So it might not be safe to run multiple instances in parallel. ++ +Besides, long-running filters may use the delayed checkout feature to +postpone the return of some filtered blobs. The delayed checkout queue +and the parallel checkout queue are not compatible and should remain +separate. ++ +Note: regular files that only require internal filters, like end-of-line +conversion and re-encoding, are eligible for parallel checkout. + +Ineligible entries are checked out by the classic sequential codepath +*before* spawning workers. + +Note: submodules's files are also eligible for parallel checkout (as +long as they don't fall into any of the excluding categories mentioned +above). But since each submodule is checked out in its own child +process, we don't mix the superproject's and the submodules' files in +the same parallel checkout process or queue. + +The API +------- + +The parallel checkout API was designed with the goal of minimizing +changes to the current users of the checkout machinery. This means that +they don't have to call a different function for sequential or parallel +checkout. As already mentioned, `checkout_entry()` will automatically +insert the given entry in the parallel checkout queue when this feature +is enabled and the entry is eligible; otherwise, it will just write the +entry right away, using the sequential code. In general, callers of the +parallel checkout API should look similar to this: + +---------------------------------------------- +int pc_workers, pc_threshold, err = 0; +struct checkout state; + +get_parallel_checkout_configs(&pc_workers, &pc_threshold); + +/* + * This check is not strictly required, but it + * should save some time in sequential mode. + */ +if (pc_workers > 1) + init_parallel_checkout(); + +for (each cache_entry ce to-be-updated) + err |= checkout_entry(ce, &state, NULL, NULL); + +err |= run_parallel_checkout(&state, pc_workers, pc_threshold, NULL, NULL); +---------------------------------------------- diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt index 85daeb5d9e..a1e31367f4 100644 --- a/Documentation/technical/protocol-v2.txt +++ b/Documentation/technical/protocol-v2.txt @@ -33,8 +33,8 @@ In protocol v2 these special packets will have the following semantics: * '0000' Flush Packet (flush-pkt) - indicates the end of a message * '0001' Delimiter Packet (delim-pkt) - separates sections of a message - * '0002' Message Packet (response-end-pkt) - indicates the end of a response - for stateless connections + * '0002' Response End Packet (response-end-pkt) - indicates the end of a + response for stateless connections Initial Client Request ---------------------- @@ -192,11 +192,20 @@ ls-refs takes in the following arguments: When specified, only references having a prefix matching one of the provided prefixes are displayed. +If the 'unborn' feature is advertised the following argument can be +included in the client's request. + + unborn + The server will send information about HEAD even if it is a symref + pointing to an unborn branch in the form "unborn HEAD + symref-target:<target>". + The output of ls-refs is as follows: output = *ref flush-pkt - ref = PKT-LINE(obj-id SP refname *(SP ref-attribute) LF) + obj-id-or-unborn = (obj-id | "unborn") + ref = PKT-LINE(obj-id-or-unborn SP refname *(SP ref-attribute) LF) ref-attribute = (symref | peeled) symref = "symref-target:" symref-target peeled = "peeled:" obj-id @@ -337,6 +346,14 @@ explained below. client should download from all given URIs. Currently, the protocols supported are "http" and "https". +If the 'wait-for-done' feature is advertised, the following argument +can be included in the client's request. + + wait-for-done + Indicates to the server that it should never send "ready", but + should wait for the client to say "done" before sending the + packfile. + The response of `fetch` is broken into a number of sections separated by delimiter packets (0001), with each section beginning with its section header. Most sections are sent only when the packfile is sent. @@ -505,3 +522,34 @@ packet-line, and must not contain non-printable or whitespace characters. The current implementation uses trace2 session IDs (see link:api-trace2.html[api-trace2] for details), but this may change and users of the session ID should not rely on this fact. + +object-info +~~~~~~~~~~~ + +`object-info` is the command to retrieve information about one or more objects. +Its main purpose is to allow a client to make decisions based on this +information without having to fully fetch objects. Object size is the only +information that is currently supported. + +An `object-info` request takes the following arguments: + + size + Requests size information to be returned for each listed object id. + + oid <oid> + Indicates to the server an object which the client wants to obtain + information for. + +The response of `object-info` is a list of the the requested object ids +and associated requested information, each separated by a single space. + + output = info flush-pkt + + info = PKT-LINE(attrs) LF) + *PKT-LINE(obj-info LF) + + attrs = attr | attrs SP attrs + + attr = "size" + + obj-info = obj-id SP obj-size diff --git a/Documentation/technical/reftable.txt b/Documentation/technical/reftable.txt index 8095ab2590..d7c3b645cf 100644 --- a/Documentation/technical/reftable.txt +++ b/Documentation/technical/reftable.txt @@ -872,17 +872,11 @@ A repository must set its `$GIT_DIR/config` to configure reftable: Layout ^^^^^^ -A collection of reftable files are stored in the `$GIT_DIR/reftable/` -directory: - -.... -00000001-00000001.log -00000002-00000002.ref -00000003-00000003.ref -.... - -where reftable files are named by a unique name such as produced by the -function `${min_update_index}-${max_update_index}.ref`. +A collection of reftable files are stored in the `$GIT_DIR/reftable/` directory. +Their names should have a random element, such that each filename is globally +unique; this helps avoid spurious failures on Windows, where open files cannot +be removed or overwritten. It suggested to use +`${min_update_index}-${max_update_index}-${random}.ref` as a naming convention. Log-only files use the `.log` extension, while ref-only and mixed ref and log files use `.ref`. extension. @@ -893,9 +887,9 @@ current files, one per line, in order, from oldest (base) to newest .... $ cat .git/reftable/tables.list -00000001-00000001.log -00000002-00000002.ref -00000003-00000003.ref +00000001-00000001-RANDOM1.log +00000002-00000002-RANDOM2.ref +00000003-00000003-RANDOM3.ref .... Readers must read `$GIT_DIR/reftable/tables.list` to determine which @@ -940,7 +934,7 @@ new reftable and atomically appending it to the stack: 3. Select `update_index` to be most recent file's `max_update_index + 1`. 4. Prepare temp reftable `tmp_XXXXXX`, including log entries. -5. Rename `tmp_XXXXXX` to `${update_index}-${update_index}.ref`. +5. Rename `tmp_XXXXXX` to `${update_index}-${update_index}-${random}.ref`. 6. Copy `tables.list` to `tables.list.lock`, appending file from (5). 7. Rename `tables.list.lock` to `tables.list`. @@ -993,7 +987,7 @@ prevents other processes from trying to compact these files. should always be the case, assuming that other processes are adhering to the locking protocol. 7. Rename `${min_update_index}-${max_update_index}_XXXXXX` to -`${min_update_index}-${max_update_index}.ref`. +`${min_update_index}-${max_update_index}-${random}.ref`. 8. Write the new stack to `tables.list.lock`, replacing `B` and `C` with the file from (4). 9. Rename `tables.list.lock` to `tables.list`. @@ -1005,6 +999,27 @@ This strategy permits compactions to proceed independently of updates. Each reftable (compacted or not) is uniquely identified by its name, so open reftables can be cached by their name. +Windows +^^^^^^^ + +On windows, and other systems that do not allow deleting or renaming to open +files, compaction may succeed, but other readers may prevent obsolete tables +from being deleted. + +On these platforms, the following strategy can be followed: on closing a +reftable stack, reload `tables.list`, and delete any tables no longer mentioned +in `tables.list`. + +Irregular program exit may still leave about unused files. In this case, a +cleanup operation should proceed as follows: + +* take a lock `tables.list.lock` to prevent concurrent modifications +* refresh the reftable stack, by reading `tables.list` +* for each `*.ref` file, remove it if +** it is not mentioned in `tables.list`, and +** its max update_index is not beyond the max update_index of the stack + + Alternatives considered ~~~~~~~~~~~~~~~~~~~~~~~ diff --git a/Documentation/technical/sparse-index.txt b/Documentation/technical/sparse-index.txt new file mode 100644 index 0000000000..3b24c1a219 --- /dev/null +++ b/Documentation/technical/sparse-index.txt @@ -0,0 +1,208 @@ +Git Sparse-Index Design Document +================================ + +The sparse-checkout feature allows users to focus a working directory on +a subset of the files at HEAD. The cone mode patterns, enabled by +`core.sparseCheckoutCone`, allow for very fast pattern matching to +discover which files at HEAD belong in the sparse-checkout cone. + +Three important scale dimensions for a Git working directory are: + +* `HEAD`: How many files are present at `HEAD`? + +* Populated: How many files are within the sparse-checkout cone. + +* Modified: How many files has the user modified in the working directory? + +We will use big-O notation -- O(X) -- to denote how expensive certain +operations are in terms of these dimensions. + +These dimensions are ordered by their magnitude: users (typically) modify +fewer files than are populated, and we can only populate files at `HEAD`. + +Problems occur if there is an extreme imbalance in these dimensions. For +example, if `HEAD` contains millions of paths but the populated set has +only tens of thousands, then commands like `git status` and `git add` can +be dominated by operations that require O(`HEAD`) operations instead of +O(Populated). Primarily, the cost is in parsing and rewriting the index, +which is filled primarily with files at `HEAD` that are marked with the +`SKIP_WORKTREE` bit. + +The sparse-index intends to take these commands that read and modify the +index from O(`HEAD`) to O(Populated). To do this, we need to modify the +index format in a significant way: add "sparse directory" entries. + +With cone mode patterns, it is possible to detect when an entire +directory will have its contents outside of the sparse-checkout definition. +Instead of listing all of the files it contains as individual entries, a +sparse-index contains an entry with the directory name, referencing the +object ID of the tree at `HEAD` and marked with the `SKIP_WORKTREE` bit. +If we need to discover the details for paths within that directory, we +can parse trees to find that list. + +At time of writing, sparse-directory entries violate expectations about the +index format and its in-memory data structure. There are many consumers in +the codebase that expect to iterate through all of the index entries and +see only files. In fact, these loops expect to see a reference to every +staged file. One way to handle this is to parse trees to replace a +sparse-directory entry with all of the files within that tree as the index +is loaded. However, parsing trees is slower than parsing the index format, +so that is a slower operation than if we left the index alone. The plan is +to make all of these integrations "sparse aware" so this expansion through +tree parsing is unnecessary and they use fewer resources than when using a +full index. + +The implementation plan below follows four phases to slowly integrate with +the sparse-index. The intention is to incrementally update Git commands to +interact safely with the sparse-index without significant slowdowns. This +may not always be possible, but the hope is that the primary commands that +users need in their daily work are dramatically improved. + +Phase I: Format and initial speedups +------------------------------------ + +During this phase, Git learns to enable the sparse-index and safely parse +one. Protections are put in place so that every consumer of the in-memory +data structure can operate with its current assumption of every file at +`HEAD`. + +At first, every index parse will call a helper method, +`ensure_full_index()`, which scans the index for sparse-directory entries +(pointing to trees) and replaces them with the full list of paths (with +blob contents) by parsing tree objects. This will be slower in all cases. +The only noticeable change in behavior will be that the serialized index +file contains sparse-directory entries. + +To start, we use a new required index extension, `sdir`, to allow +inserting sparse-directory entries into indexes with file format +versions 2, 3, and 4. This prevents Git versions that do not understand +the sparse-index from operating on one, while allowing tools that do not +understand the sparse-index to operate on repositories as long as they do +not interact with the index. A new format, index v5, will be introduced +that includes sparse-directory entries by default. It might also +introduce other features that have been considered for improving the +index, as well. + +Next, consumers of the index will be guarded against operating on a +sparse-index by inserting calls to `ensure_full_index()` or +`expand_index_to_path()`. If a specific path is requested, then those will +be protected from within the `index_file_exists()` and `index_name_pos()` +API calls: they will call `ensure_full_index()` if necessary. The +intention here is to preserve existing behavior when interacting with a +sparse-checkout. We don't want a change to happen by accident, without +tests. Many of these locations may not need any change before removing the +guards, but we should not do so without tests to ensure the expected +behavior happens. + +It may be desirable to _change_ the behavior of some commands in the +presence of a sparse index or more generally in any sparse-checkout +scenario. In such cases, these should be carefully communicated and +tested. No such behavior changes are intended during this phase. + +During a scan of the codebase, not every iteration of the cache entries +needs an `ensure_full_index()` check. The basic reasons include: + +1. The loop is scanning for entries with non-zero stage. These entries + are not collapsed into a sparse-directory entry. + +2. The loop is scanning for submodules. These entries are not collapsed + into a sparse-directory entry. + +3. The loop is part of the index API, especially around reading or + writing the format. + +4. The loop is checking for correct order of cache entries and that is + correct if and only if the sparse-directory entries are in the correct + location. + +5. The loop ignores entries with the `SKIP_WORKTREE` bit set, or is + otherwise already aware of sparse directory entries. + +6. The sparse-index is disabled at this point when using the split-index + feature, so no effort is made to protect the split-index API. + +Even after inserting these guards, we will keep expanding sparse-indexes +for most Git commands using the `command_requires_full_index` repository +setting. This setting will be on by default and disabled one builtin at a +time until we have sufficient confidence that all of the index operations +are properly guarded. + +To complete this phase, the commands `git status` and `git add` will be +integrated with the sparse-index so that they operate with O(Populated) +performance. They will be carefully tested for operations within and +outside the sparse-checkout definition. + +Phase II: Careful integrations +------------------------------ + +This phase focuses on ensuring that all index extensions and APIs work +well with a sparse-index. This requires significant increases to our test +coverage, especially for operations that interact with the working +directory outside of the sparse-checkout definition. Some of these +behaviors may not be the desirable ones, such as some tests already +marked for failure in `t1092-sparse-checkout-compatibility.sh`. + +The index extensions that may require special integrations are: + +* FS Monitor +* Untracked cache + +While integrating with these features, we should look for patterns that +might lead to better APIs for interacting with the index. Coalescing +common usage patterns into an API call can reduce the number of places +where sparse-directories need to be handled carefully. + +Phase III: Important command speedups +------------------------------------- + +At this point, the patterns for testing and implementing sparse-directory +logic should be relatively stable. This phase focuses on updating some of +the most common builtins that use the index to operate as O(Populated). +Here is a potential list of commands that could be valuable to integrate +at this point: + +* `git commit` +* `git checkout` +* `git merge` +* `git rebase` + +Hopefully, commands such as `git merge` and `git rebase` can benefit +instead from merge algorithms that do not use the index as a data +structure, such as the merge-ORT strategy. As these topics mature, we +may enable the ORT strategy by default for repositories using the +sparse-index feature. + +Along with `git status` and `git add`, these commands cover the majority +of users' interactions with the working directory. In addition, we can +integrate with these commands: + +* `git grep` +* `git rm` + +These have been proposed as some whose behavior could change when in a +repo with a sparse-checkout definition. It would be good to include this +behavior automatically when using a sparse-index. Some clarity is needed +to make the behavior switch clear to the user. + +This phase is the first where parallel work might be possible without too +much conflicts between topics. + +Phase IV: The long tail +----------------------- + +This last phase is less a "phase" and more "the new normal" after all of +the previous work. + +To start, the `command_requires_full_index` option could be removed in +favor of expanding only when hitting an API guard. + +There are many Git commands that could use special attention to operate as +O(Populated), while some might be so rare that it is acceptable to leave +them with additional overhead when a sparse-index is present. + +Here are some commands that might be useful to update: + +* `git sparse-checkout set` +* `git am` +* `git clean` +* `git stash` diff --git a/Documentation/user-manual.txt b/Documentation/user-manual.txt index fd480b8645..f9e54b8674 100644 --- a/Documentation/user-manual.txt +++ b/Documentation/user-manual.txt @@ -1,5 +1,8 @@ = Git User Manual +[preface] +== Introduction + Git is a fast distributed revision control system. This manual is designed to be readable by someone with basic UNIX |