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2021-10-25Merge branch 'jc/doc-commit-header-continuation-line'Libravatar Junio C Hamano1-4/+20
Doc update. * jc/doc-commit-header-continuation-line: signature-format.txt: explain and illustrate multi-line headers
2021-10-13Merge branch 'jh/builtin-fsmonitor-part1'Libravatar Junio C Hamano1-0/+40
Built-in fsmonitor (part 1). * jh/builtin-fsmonitor-part1: t/helper/simple-ipc: convert test-simple-ipc to use start_bg_command run-command: create start_bg_command simple-ipc/ipc-win32: add Windows ACL to named pipe simple-ipc/ipc-win32: add trace2 debugging simple-ipc: move definition of ipc_active_state outside of ifdef simple-ipc: preparations for supporting binary messages. trace2: add trace2_child_ready() to report on background children
2021-10-12signature-format.txt: explain and illustrate multi-line headersLibravatar Junio C Hamano1-4/+20
A signature attached to a signed commit, and the contents of the commit that merged a signed tag, are both recorded as a value of an object header field as a multi-line value, and are subject to the formatting convention for multi-line values in the headers, with a leading SP signaling that the rest of the line is a continuation of the previous line. Most notably, an empty line in such a multi-line value would result in a line with a sole SP on it. Examples in the signature-format technical documentation include a few of these cases but we did not show these otherwise invisible SPs in the example. These trailing spaces cannot be seen on display or on paper, and forces the readers to look for them in their editors or pagers, even if we added them to the document. Extend the overview section to explain the multi-line value formatting and highlight these otherwise invisible SPs by inventing the "a dollar-sign at the end of line that appears after SP merely signals that there is a SP there, and the dollar-sign itself does not appear in the real file" notation, inspired by "cat -e" output, to help readers to learn exactly where such "a single SP that is originally an empty line" appears in the examples. Reported-by: Rob Browning <rlb@defaultvalue.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-06Merge branch 'ew/midx-doc-update'Libravatar Junio C Hamano1-1/+3
Doc tweak. * ew/midx-doc-update: doc/technical: update note about core.multiPackIndex
2021-09-28Merge branch 'jk/reduce-malloc-in-v2-servers'Libravatar Junio C Hamano1-1/+5
Code cleanup to limit memory consumption and tighten protocol message parsing. * jk/reduce-malloc-in-v2-servers: ls-refs: reject unknown arguments serve: reject commands used as capabilities serve: reject bogus v2 "command=ls-refs=foo" docs/protocol-v2: clarify some ls-refs ref-prefix details ls-refs: ignore very long ref-prefix counts serve: drop "keys" strvec serve: provide "receive" function for session-id capability serve: provide "receive" function for object-format capability serve: add "receive" method for v2 capabilities table serve: return capability "value" from get_capability() serve: rename is_command() to parse_command()
2021-09-24doc/technical: update note about core.multiPackIndexLibravatar Eric Wong1-1/+3
MIDX files are used by default since commit 18e449f86b74 (midx: enable core.multiPackIndex by default, 2020-09-25) Helped-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Eric Wong <e@80x24.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-23Merge branch 'ab/retire-option-argument'Libravatar Junio C Hamano1-5/+0
An oddball OPTION_ARGUMENT feature has been removed from the parse-options API. * ab/retire-option-argument: parse-options API: remove OPTION_ARGUMENT feature difftool: use run_command() API in run_file_diff() difftool: prepare "diff" cmdline in cmd_difftool() difftool: prepare "struct child_process" in cmd_difftool()
2021-09-23Merge branch 'jk/http-server-protocol-versions'Libravatar Junio C Hamano1-1/+7
Taking advantage of the CGI interface, http-backend has been updated to enable protocol v2 automatically when the other side asks for it. * jk/http-server-protocol-versions: docs/protocol-v2: point readers transport config discussion docs/git: discuss server-side config for GIT_PROTOCOL docs/http-backend: mention v2 protocol http-backend: handle HTTP_GIT_PROTOCOL CGI variable t5551: test v2-to-v0 http protocol fallback
2021-09-20Merge branch 'ab/serve-cleanup'Libravatar Junio C Hamano2-0/+6
Code clean-up around "git serve". * ab/serve-cleanup: upload-pack: document and rename --advertise-refs serve.[ch]: remove "serve_options", split up --advertise-refs code {upload,receive}-pack tests: add --advertise-refs tests serve.c: move version line to advertise_capabilities() serve: move transfer.advertiseSID check into session_id_advertise() serve.[ch]: don't pass "struct strvec *keys" to commands serve: use designated initializers transport: use designated initializers transport: rename "fetch" in transport_vtable to "fetch_refs" serve: mark has_capability() as static
2021-09-20Merge branch 'tb/multi-pack-bitmaps'Libravatar Junio C Hamano2-21/+60
The reachability bitmap file used to be generated only for a single pack, but now we've learned to generate bitmaps for history that span across multiple packfiles. * tb/multi-pack-bitmaps: (29 commits) pack-bitmap: drop bitmap_index argument from try_partial_reuse() pack-bitmap: drop repository argument from prepare_midx_bitmap_git() p5326: perf tests for MIDX bitmaps p5310: extract full and partial bitmap tests midx: respect 'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP' t7700: update to work with MIDX bitmap test knob t5319: don't write MIDX bitmaps in t5319 t5310: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP t0410: disable GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP t5326: test multi-pack bitmap behavior t/helper/test-read-midx.c: add --checksum mode t5310: move some tests to lib-bitmap.sh pack-bitmap: write multi-pack bitmaps pack-bitmap: read multi-pack bitmaps pack-bitmap.c: avoid redundant calls to try_partial_reuse pack-bitmap.c: introduce 'bitmap_is_preferred_refname()' pack-bitmap.c: introduce 'nth_bitmap_object_oid()' pack-bitmap.c: introduce 'bitmap_num_objects()' midx: avoid opening multiple MIDXs when writing midx: close linked MIDXs, avoid leaking memory ...
2021-09-20trace2: add trace2_child_ready() to report on background childrenLibravatar Jeff Hostetler1-0/+40
Create "child_ready" event to capture the state of a child process created in the background. When a child command is started a "child_start" event is generated in the Trace2 log. For normal synchronous children, a "child_exit" event is later generated when the child exits or is terminated. The two events include information, such as the "child_id" and "pid", to allow post analysis to match-up the command line and exit status. When a child is started in the background (and may outlive the parent process), it is not possible for the parent to emit a "child_exit" event. Create a new "child_ready" event to indicate whether the child was successfully started. Also include the "child_id" and "pid" to allow similar post processing. This will be used in a later commit with the new "start_bg_command()". Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-15docs/protocol-v2: clarify some ls-refs ref-prefix detailsLibravatar Jeff King1-1/+5
We've never documented the fact that a client can provide multiple ref-prefix capabilities. Let's describe the behavior. We also never discussed the "best effort" nature of the prefixes. The client side of git.git has always treated them this way, filtering the result with local patterns. And indeed any client must do this, because the prefix patterns are not sufficient to express the usual refspecs (and so for "foo" we ask for "refs/heads/foo", "refs/tags/foo", and so on). So this may be considered a change in the spec with respect to client expectations / requirements, but it's mostly codifying existing behavior. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-14Merge branch 'ab/serve-cleanup' into jk/reduce-malloc-in-v2-serversLibravatar Junio C Hamano2-0/+6
* ab/serve-cleanup: upload-pack: document and rename --advertise-refs serve.[ch]: remove "serve_options", split up --advertise-refs code {upload,receive}-pack tests: add --advertise-refs tests serve.c: move version line to advertise_capabilities() serve: move transfer.advertiseSID check into session_id_advertise() serve.[ch]: don't pass "struct strvec *keys" to commands serve: use designated initializers transport: use designated initializers transport: rename "fetch" in transport_vtable to "fetch_refs" serve: mark has_capability() as static
2021-09-12parse-options API: remove OPTION_ARGUMENT featureLibravatar Ævar Arnfjörð Bjarmason1-5/+0
As was noted in 1a85b49b87a (parse-options: make OPT_ARGUMENT() more useful, 2019-03-14) there's only ever been one user of the OPT_ARGUMENT(), that user was added in 20de316e334 (difftool: allow running outside Git worktrees with --no-index, 2019-03-14). The OPT_ARGUMENT() feature itself was added way back in 580d5bffdea (parse-options: new option type to treat an option-like parameter as an argument., 2008-03-02), but as discussed in 1a85b49b87a wasn't used until 20de316e334 in 2019. Now that the preceding commit has migrated this code over to using "struct strvec" to manage the "args" member of a "struct child_process", we can just use that directly instead of relying on OPT_ARGUMENT. This has a minor change in behavior in that if we'll pass --no-index we'll now always pass it as the first argument, before we'd pass it in whatever position the caller did. Preserving this was the real value of OPT_ARGUMENT(), but as it turns out we didn't need that either. We can always inject it as the first argument, the other end will parse it just the same. Note that we cannot remove the "out" and "cpidx" members of "struct parse_opt_ctx_t" added in 580d5bffdea, while they were introduced with OPT_ARGUMENT() we since used them for other things. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-09-10docs/protocol-v2: point readers transport config discussionLibravatar Jeff King1-1/+7
We recently added tips for server admins to configure various transports to support v2's GIT_PROTOCOL variable. While the protocol-v2 document is pretty technical and not of interest to most admins, it may be a starting point for them to figure out how to turn on v2. Let's put some pointers from there to the other documentation. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-30Merge branch 'en/merge-strategy-docs'Libravatar Junio C Hamano1-6/+8
Documentation updates. * en/merge-strategy-docs: Update error message and code comment merge-strategies.txt: add coverage of the `ort` merge strategy git-rebase.txt: correct out-of-date and misleading text about renames merge-strategies.txt: fix simple capitalization error merge-strategies.txt: avoid giving special preference to patience algorithm merge-strategies.txt: do not imply using copy detection is desired merge-strategies.txt: update wording for the resolve strategy Documentation: edit awkward references to `git merge-recursive` directory-rename-detection.txt: small updates due to merge-ort optimizations git-rebase.txt: correct antiquated claims about --rebase-merges
2021-08-24Merge branch 'es/trace2-log-parent-process-name'Libravatar Junio C Hamano1-0/+14
trace2 logs learned to show parent process name to see in what context Git was invoked. * es/trace2-log-parent-process-name: tr2: log parent process name tr2: make process info collection platform-generic
2021-08-24Documentation: describe MIDX-based bitmapsLibravatar Taylor Blau2-21/+60
Update the technical documentation to describe the multi-pack bitmap format. This patch merely introduces the new format, and describes its high-level ideas. Git does not yet know how to read nor write these multi-pack variants, and so the subsequent patches will: - Introduce code to interpret multi-pack bitmaps, according to this document. - Then, introduce code to write multi-pack bitmaps from the 'git multi-pack-index write' sub-command. Finally, the implementation will gain tests in subsequent patches (as opposed to inline with the patch teaching Git how to write multi-pack bitmaps) to avoid a cyclic dependency. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-05upload-pack: document and rename --advertise-refsLibravatar Ævar Arnfjörð Bjarmason2-0/+6
The --advertise-refs documentation in git-upload-pack added in 9812f2136b3 (upload-pack.c: use parse-options API, 2016-05-31) hasn't been entirely true ever since v2 support was implemented in e52449b6722 (connect: request remote refs using v2, 2018-03-15). Under v2 we don't advertise the refs at all, but rather dump the capabilities header. This option has always been an obscure internal implementation detail, it wasn't even documented for git-receive-pack. Since it has exactly one user let's rename it to --http-backend-info-refs, which is more accurate and points the reader in the right direction. Let's also cross-link this from the protocol v1 and v2 documentation. I'm retaining a hidden --advertise-refs alias in case there's any external users of this, and making both options hidden to the bash completion (as with most other internal-only options). Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-05directory-rename-detection.txt: small updates due to merge-ort optimizationsLibravatar Elijah Newren1-6/+8
In commit 0c4fd732f0 ("Move computation of dir_rename_count from merge-ort to diffcore-rename", 2021-02-27), much of the logic for computing directory renames moved into diffcore-rename. directory-rename-detection.txt had claims that all of that logic was found in merge-recursive. Update the documentation. Acked-by: Derrick Stolee <dstolee@microsoft.com> Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-22tr2: log parent process nameLibravatar Emily Shaffer1-0/+14
It can be useful to tell who invoked Git - was it invoked manually by a user via CLI or script? By an IDE? In some cases - like 'repo' tool - we can influence the source code and set the GIT_TRACE2_PARENT_SID environment variable from the caller process. In 'repo''s case, that parent SID is manipulated to include the string "repo", which means we can positively identify when Git was invoked by 'repo' tool. However, identifying parents that way requires both that we know which tools invoke Git and that we have the ability to modify the source code of those tools. It cannot scale to keep up with the various IDEs and wrappers which use Git, most of which we don't know about. Learning which tools and wrappers invoke Git, and how, would give us insight to decide where to improve Git's usability and performance. Unfortunately, there's no cross-platform reliable way to gather the name of the parent process. If procfs is present, we can use that; otherwise we will need to discover the name another way. However, the process ID should be sufficient to look up the process name on most platforms, so that code may be shareable. Git for Windows gathers similar information and logs it as a "data_json" event. However, since "data_json" has a variable format, it is difficult to parse effectively in some languages; instead, let's pursue a dedicated "cmd_ancestry" event to record information about the ancestry of the current process and a consistent, parseable way. Git for Windows also gathers information about more than one generation of parent. In Linux further ancestry info can be gathered with procfs, but it's unwieldy to do so. In the interest of later moving Git for Windows ancestry logging to the 'cmd_ancestry' event, and in the interest of later adding more ancestry to the Linux implementation - or of adding this functionality to other platforms which have an easier time walking the process tree - let's make 'cmd_ancestry' accept an array of parentage. Signed-off-by: Emily Shaffer <emilyshaffer@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-07-08Merge branch 'ar/typofix'Libravatar Junio C Hamano2-2/+2
Typofixes. * ar/typofix: *: fix typos which duplicate a word
2021-07-08Merge branch 'js/trace2-discard-event-docfix'Libravatar Junio C Hamano1-2/+2
Docfix. * js/trace2-discard-event-docfix: docs: fix api-trace2 doc for "too_many_files" event
2021-07-08Merge branch 'tk/partial-clone-repack-doc'Libravatar Junio C Hamano1-5/+1
Docfix. * tk/partial-clone-repack-doc: Remove warning that repack only works on non-promisor packfiles
2021-06-14Merge branch 'en/ort-perf-batch-11'Libravatar Junio C Hamano1-0/+671
Optimize out repeated rename detection in a sequence of mergy operations. * en/ort-perf-batch-11: merge-ort, diffcore-rename: employ cached renames when possible merge-ort: handle interactions of caching and rename/rename(1to1) cases merge-ort: add helper functions for using cached renames merge-ort: preserve cached renames for the appropriate side merge-ort: avoid accidental API mis-use merge-ort: add code to check for whether cached renames can be reused merge-ort: populate caches of rename detection results merge-ort: add data structures for in-memory caching of rename detection t6429: testcases for remembering renames fast-rebase: write conflict state to working tree, index, and HEAD fast-rebase: change assert() to BUG() Documentation/technical: describe remembering renames optimization t6423: rename file within directory that other side renamed
2021-06-14*: fix typos which duplicate a wordLibravatar Andrei Rybak2-2/+2
Fix typos in documentation, code comments, and RelNotes which repeat various words. In trivial cases, just delete the duplicated word and rewrap text, if needed. Reword the affected sentence in Documentation/RelNotes/1.8.4.txt for it to make sense. Signed-off-by: Andrei Rybak <rybak.a.v@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-10Merge branch 'tl/fix-packfile-uri-doc'Libravatar Junio C Hamano1-7/+8
Doc fix. * tl/fix-packfile-uri-doc: packfile-uri.txt: fix blobPackfileUri description
2021-06-04docs: fix api-trace2 doc for "too_many_files" eventLibravatar Josh Steadmon1-2/+2
In 87db61a (trace2: write discard message to sentinel files, 2019-10-04), we added a new "too_many_files" event for when trace2 logging would create too many files in an output directory. Unfortunately, the api-trace2 doc described a "discard" event instead. Fix the doc to use the correct event name. Signed-off-by: Josh Steadmon <steadmon@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-06-04Remove warning that repack only works on non-promisor packfilesLibravatar Tao Klerks1-5/+1
The git-repack doc clearly states that it *does* operate on promisor packfiles (in a separate partition), with "-a" specified. Presumably the statements here are outdated, as they feature from the first doc in 2017 (and the repack support was added in 2018) Signed-off-by: Tao Klerks <tao@klerks.biz> Reviewed-by: Taylor Blau <me@ttaylorr.com> Acked-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-25packfile-uri.txt: fix blobPackfileUri descriptionLibravatar Teng Long1-7/+8
Fix the 'uploadpack.blobPackfileUri' description in packfile-uri.txt and the correct format also can be seen in t5702. Signed-off-by: Teng Long <dyroneteng@gmail.com> Reviewed-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-20t6429: testcases for remembering renamesLibravatar Elijah Newren1-6/+8
We will soon be adding an optimization that caches (in memory only, never written to disk) upstream renames during a sequence of merges such as occurs during a cherry-pick or rebase operation. Add several tests meant to stress such an implementation to ensure it does the right thing, and include a test whose outcome we will later change due to this optimization as well. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-20Documentation/technical: describe remembering renames optimizationLibravatar Elijah Newren1-0/+669
Remembering renames on the upstream side of history in an early merge of a rebase or cherry-pick for re-use in a latter merge of the same operation makes pretty good intuitive sense. However, trying to show that it doesn't cause some subtle behavioral difference or some funny edge or corner case is much more involved. And, in fact, it does introduce a subtle behavioral change. Document all the assumptions, special cases, and logic involved in such an optimization, and describe why this optimization is safe under the current optimizations/features/etc. -- even when the subtle behavioral change is triggered. Part of the point of adding this document that goes over the optimization in such laborious detail, is that it is possible that significant future changes (optimizations or feature changes) could interact with this optimization in interesting ways; this document is here to help folks making big changes sanity check that the assumptions and arguments underlying this optimization are still valid. (As a side note, creating this document forced me to review things in sufficient detail that I found I was not properly caching directory-rename-induced renames, resulting in the code not being aware of those renames and causing unnecessary diffcore_rename_extended() calls in subsequent merges.) A subsequent commit will add several testcases based on this document meant to stress-test the implementation and also document the case with the subtle behavioral change. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-16Merge branch 'jt/push-negotiation'Libravatar Junio C Hamano1-0/+8
"git push" learns to discover common ancestor with the receiving end over protocol v2. * jt/push-negotiation: send-pack: support push negotiation fetch: teach independent negotiation (no packfile) fetch-pack: refactor command and capability write fetch-pack: refactor add_haves() fetch-pack: refactor process_acks()
2021-05-14Merge branch 'ba/object-info'Libravatar Junio C Hamano1-0/+31
Over-the-wire protocol learns a new request type to ask for object sizes given a list of object names. * ba/object-info: object-info: support for retrieving object info
2021-05-05fetch: teach independent negotiation (no packfile)Libravatar Jonathan Tan1-0/+8
Currently, the packfile negotiation step within a Git fetch cannot be done independent of sending the packfile, even though there is at least one application wherein this is useful. Therefore, make it possible for this negotiation step to be done independently. A subsequent commit will use this for one such application - push negotiation. This feature is for protocol v2 only. (An implementation for protocol v0 would require a separate implementation in the fetch, transport, and transport helper code.) In the protocol, the main hindrance towards independent negotiation is that the server can unilaterally decide to send the packfile. This is solved by a "wait-for-done" argument: the server will then wait for the client to say "done". In practice, the client will never say it; instead it will cease requests once it is satisfied. In the client, the main change lies in the transport and transport helper code. fetch_refs_via_pack() performs everything needed - protocol version and capability checks, and the negotiation itself. There are 2 code paths that do not go through fetch_refs_via_pack() that needed to be individually excluded: the bundle transport (excluded through requiring smart_options, which the bundle transport doesn't support) and transport helpers that do not support takeover. If or when we support independent negotiation for protocol v0, we will need to modify these 2 code paths to support it. But for now, report failure if independent negotiation is requested in these cases. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-30Merge branch 'mt/parallel-checkout-part-2'Libravatar Junio C Hamano1-0/+270
The checkout machinery has been taught to perform the actual write-out of the files in parallel when able. * mt/parallel-checkout-part-2: parallel-checkout: add design documentation parallel-checkout: support progress displaying parallel-checkout: add configuration options parallel-checkout: make it truly parallel unpack-trees: add basic support for parallel checkout
2021-04-30Merge branch 'ds/sparse-index-protections'Libravatar Junio C Hamano2-0/+227
Builds on top of the sparse-index infrastructure to mark operations that are not ready to mark with the sparse index, causing them to fall back on fully-populated index that they always have worked with. * ds/sparse-index-protections: (47 commits) name-hash: use expand_to_path() sparse-index: expand_to_path() name-hash: don't add directories to name_hash revision: ensure full index resolve-undo: ensure full index read-cache: ensure full index pathspec: ensure full index merge-recursive: ensure full index entry: ensure full index dir: ensure full index update-index: ensure full index stash: ensure full index rm: ensure full index merge-index: ensure full index ls-files: ensure full index grep: ensure full index fsck: ensure full index difftool: ensure full index commit: ensure full index checkout: ensure full index ...
2021-04-20object-info: support for retrieving object infoLibravatar Bruno Albuquerque1-0/+31
Sometimes it is useful to get information of an object without having to download it completely. Add the "object-info" capability that lets the client ask for object-related information with their full hexadecimal object names. Only sizes are returned for now. Signed-off-by: Bruno Albuquerque <bga@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-20Merge branch 'ab/usage-error-docs'Libravatar Junio C Hamano2-3/+9
Documentation updates, with unrelated comment updates, too. * ab/usage-error-docs: api docs: document that BUG() emits a trace2 error event api docs: document BUG() in api-error-handling.txt usage.c: don't copy/paste the same comment three times
2021-04-20Merge branch 'hn/reftable-tables-doc-update'Libravatar Junio C Hamano1-2/+7
Doc updte. * hn/reftable-tables-doc-update: reftable: document an alternate cleanup method on Windows
2021-04-19parallel-checkout: add design documentationLibravatar Matheus Tavares1-0/+270
Co-authored-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-14sparse-index: API protection strategyLibravatar Derrick Stolee1-2/+35
Edit and expand the sparse-index design document with the plan for guarding index operations with ensure_full_index(). Notably, the plan has changed to not have an expand_to_path() method in favor of checking for a sparse-directory hit inside of the index_path_pos() API. The changes that follow this one will incrementally add ensure_full_index() guards to iterations over all cache entries. Some iterations over the cache entries are not protected due to a few categories listed in the document. Since these are not being modified, here is a short list of the files and methods that will not receive these guards: Looking for non-zero stage: * builtin/add.c:chmod_pathspec() * builtin/merge.c:count_unmerged_entries() * merge-ort.c:record_conflicted_index_entries() * read-cache.c:unmerged_index() * rerere.c:check_one_conflict(), find_conflict(), rerere_remaining() * revision.c:prepare_show_merge() * sequencer.c:append_conflicts_hint() * wt-status.c:wt_status_collect_changes_initial() Looking for submodules: * builtin/submodule--helper.c:module_list_compute() * submodule.c: several methods * worktree.c:validate_no_submodules() Part of the index API: * name-hash.c: lazy init methods * preload-index.c:preload_thread(), preload_index() * read-cache.c: file format methods Checking for correct order of cache entries: * read-cache.c:check_ce_order() Ignores SKIP_WORKTREE entries or already aware: * unpack-trees.c:mark_new_skip_worktree() * wt-status.c:wt_status_check_sparse_checkout() Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-13api docs: document that BUG() emits a trace2 error eventLibravatar Ævar Arnfjörð Bjarmason2-1/+4
Correct documentation added in e544221d97a (trace2: Documentation/technical/api-trace2.txt, 2019-02-22) to state that calling BUG() also emits an "error" event. See ee4512ed481 (trace2: create new combined trace facility, 2019-02-22) for the initial implementation. The BUG() function did not emit an event then however, that was only changed later in 0a9dde4a04c (usage: trace2 BUG() invocations, 2021-02-05), that commit changed the code, but didn't update any of the docs. Let's also add a cross-reference from api-error-handling.txt. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-13api docs: document BUG() in api-error-handling.txtLibravatar Ævar Arnfjörð Bjarmason1-2/+5
When the BUG() function was added in d8193743e08 (usage.c: add BUG() function, 2017-05-12) these docs added in 1f23cfe0ef5 (doc: document error handling functions and conventions, 2014-12-03) were not updated. Let's do that. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-12reftable: document an alternate cleanup method on WindowsLibravatar Han-Wen Nienhuys1-2/+7
The new method uses the update_index counter, which isn't susceptible to clock inaccuracies. Signed-off-by: Han-Wen Nienhuys <hanwen@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-08Merge branch 'tb/reverse-midx'Libravatar Junio C Hamano2-2/+86
An on-disk reverse-index to map the in-pack location of an object back to its object name across multiple packfiles is introduced. * tb/reverse-midx: midx.c: improve cache locality in midx_pack_order_cmp() pack-revindex: write multi-pack reverse indexes pack-write.c: extract 'write_rev_file_order' pack-revindex: read multi-pack reverse indexes Documentation/technical: describe multi-pack reverse indexes midx: make some functions non-static midx: keep track of the checksum midx: don't free midx_name early midx: allow marking a pack as preferred t/helper/test-read-midx.c: add '--show-objects' builtin/multi-pack-index.c: display usage on unrecognized command builtin/multi-pack-index.c: don't enter bogus cmd_mode builtin/multi-pack-index.c: split sub-commands builtin/multi-pack-index.c: define common usage with a macro builtin/multi-pack-index.c: don't handle 'progress' separately builtin/multi-pack-index.c: inline 'flags' with options
2021-04-02Merge branch 'jh/simple-ipc'Libravatar Junio C Hamano1-0/+105
A simple IPC interface gets introduced to build services like fsmonitor on top. * jh/simple-ipc: t0052: add simple-ipc tests and t/helper/test-simple-ipc tool simple-ipc: add Unix domain socket implementation unix-stream-server: create unix domain socket under lock unix-socket: disallow chdir() when creating unix domain sockets unix-socket: add backlog size option to unix_stream_listen() unix-socket: eliminate static unix_stream_socket() helper function simple-ipc: add win32 implementation simple-ipc: design documentation for new IPC mechanism pkt-line: add options argument to read_packetized_to_strbuf() pkt-line: add PACKET_READ_GENTLE_ON_READ_ERROR option pkt-line: do not issue flush packets in write_packetized_*() pkt-line: eliminate the need for static buffer in packet_write_gently()
2021-04-01Documentation/technical: describe multi-pack reverse indexesLibravatar Taylor Blau1-0/+83
As a prerequisite to implementing multi-pack bitmaps, motivate and describe the format and ordering of the multi-pack reverse index. The subsequent patch will implement reading this format, and the patch after that will implement writing it while producing a multi-pack index. Co-authored-by: Jeff King <peff@peff.net> Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-01midx: allow marking a pack as preferredLibravatar Taylor Blau1-2/+3
When multiple packs in the multi-pack index contain the same object, the MIDX machinery must make a choice about which pack it associates with that object. Prior to this patch, the lowest-ordered[1] pack was always selected. Pack selection for duplicate objects is relatively unimportant today, but it will become important for multi-pack bitmaps. This is because we can only invoke the pack-reuse mechanism when all of the bits for reused objects come from the reuse pack (in order to ensure that all reused deltas can find their base objects in the same pack). To encourage the pack selection process to prefer one pack over another (the pack to be preferred is the one a caller would like to later use as a reuse pack), introduce the concept of a "preferred pack". When provided, the MIDX code will always prefer an object found in a preferred pack over any other. No format changes are required to store the preferred pack, since it will be able to be inferred with a corresponding MIDX bitmap, by looking up the pack associated with the object in the first bit position (this ordering is described in detail in a subsequent commit). [1]: the ordering is specified by MIDX internals; for our purposes we can consider the "lowest ordered" pack to be "the one with the most-recent mtime. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-30sparse-index: add 'sdir' index extensionLibravatar Derrick Stolee1-0/+12
The index format does not currently allow for sparse directory entries. This violates some expectations that older versions of Git or third-party tools might not understand. We need an indicator inside the index file to warn these tools to not interact with a sparse index unless they are aware of sparse directory entries. Add a new _required_ index extension, 'sdir', that indicates that the index may contain sparse directory entries. This allows us to continue to use the differences in index formats 2, 3, and 4 before we create a new index version 5 in a later change. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>