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2017-09-06lockfile: do not rollback lock on failed closeLibravatar Jeff King1-1/+1
Since the lockfile code is based on the tempfile code, it has some of the same problems, including that close_lock_file() erases the tempfile's filename buf, making it hard for the caller to write a good error message. In practice this comes up less for lockfiles than for straight tempfiles, since we usually just report the refname. But there is at least one buggy case in write_ref_to_lockfile(). Besides, given the coupling between the lockfile and tempfile modules, it's less confusing if their close() functions have the same semantics. Just as the previous commit did for close_tempfile(), let's teach close_lock_file() and its wrapper close_ref() not to rollback on error. And just as before, we'll give them new "gently" names to catch any new callers that are added. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-09-06tempfile: do not delete tempfile on failed closeLibravatar Jeff King1-2/+5
When close_tempfile() fails, we delete the tempfile and reset the fields of the tempfile struct. This makes it easier for callers to return without cleaning up, but it also makes this common pattern: if (close_tempfile(tempfile)) return error_errno("error closing %s", tempfile->filename.buf); wrong, because the "filename" field has been reset after the failed close. And it's not easy to fix, as in many cases we don't have another copy of the filename (e.g., if it was created via one of the mks_tempfile functions, and we just have the original template string). Let's drop the feature that a failed close automatically deletes the file. This puts the burden on the caller to do the deletion themselves, but this isn't that big a deal. Callers which do: if (write(...) || close_tempfile(...)) { delete_tempfile(...); return -1; } already had to call delete when the write() failed, and so aren't affected. Likewise, any caller which just calls die() in the error path is OK; we'll delete the tempfile during the atexit handler. Because this patch changes the semantics of close_tempfile() without changing its signature, all callers need to be manually checked and converted to the new scheme. This patch covers all in-tree callers, but there may be others for not-yet-merged topics. To catch these, we rename the function to close_tempfile_gently(), which will attract compile-time attention to new callers. (Technically the original could be considered "gentle" already in that it didn't die() on errors, but this one is even more so). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-26Merge branch 'kw/write-index-reduce-alloc'Libravatar Junio C Hamano1-28/+34
We used to spend more than necessary cycles allocating and freeing piece of memory while writing each index entry out. This has been optimized. * kw/write-index-reduce-alloc: read-cache: avoid allocating every ondisk entry when writing read-cache: fix memory leak in do_write_index perf: add test for writing the index
2017-08-21read-cache: avoid allocating every ondisk entry when writingLibravatar Kevin Willford1-25/+25
When writing the index for each entry an ondisk struct will be allocated and freed in ce_write_entry. We can do better by using a ondisk struct on the stack for each entry. This is accomplished by using a stack ondisk_cache_entry_extended outside looping through the entries in do_write_index. Only the fixed fields of this struct are used when writing and depending on whether it is extended or not the flags2 field will be written. The name field is not used and instead the cache_entry name field is used directly when writing out the name. Because ce_write is using a buffer and memcpy to fill the buffer before flushing to disk, we don't have to worry about doing multiple ce_write calls. Running the p0007-write-cache.sh tests would save anywhere between 3-7% when the index had over a million entries with no performance degradation on small repos. Signed-off-by: Kevin Willford <kewillf@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-21read-cache: fix memory leak in do_write_indexLibravatar Kevin Willford1-3/+9
The previous_name_buf was never getting released when there was an error in ce_write_entry or allow was false and execution was returned to the caller. Signed-off-by: Kevin Willford <kewillf@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-20sha1_file: convert index_fd to struct object_idLibravatar Patryk Obara1-1/+1
Convert all remaining callers as well. Signed-off-by: Patryk Obara <patryk.obara@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-20sha1_file: convert index_path to struct object_idLibravatar Patryk Obara1-1/+1
Convert all remaining callers as well. Signed-off-by: Patryk Obara <patryk.obara@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-20read-cache: convert to struct object_idLibravatar Patryk Obara1-3/+3
Replace hashcmp with oidcmp. Signed-off-by: Patryk Obara <patryk.obara@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-17use MOVE_ARRAYLibravatar René Scharfe1-3/+2
Simplify the code for moving members inside of an array and make it more robust by using the helper macro MOVE_ARRAY. It calculates the size based on the specified number of elements for us and supports NULL pointers when that number is zero. Raw memmove(3) calls with NULL can cause the compiler to (over-eagerly) optimize out later NULL checks. This patch was generated with contrib/coccinelle/array.cocci and spatch (Coccinelle). Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-05Merge branch 'cc/shared-index-permfix'Libravatar Junio C Hamano1-0/+8
The split index code did not honor core.sharedrepository setting correctly. * cc/shared-index-permfix: t1700: make sure split-index respects core.sharedrepository t1301: move modebits() to test-lib-functions.sh read-cache: use shared perms when writing shared index
2017-06-25read-cache: use shared perms when writing shared indexLibravatar Christian Couder1-0/+8
Since f6ecc62dbf (write_shared_index(): use tempfile module, 2015-08-10) write_shared_index() has been using mks_tempfile() to create the temporary file that will become the shared index. But even before that, it looks like the functions used to create this file didn't call adjust_shared_perm(), which means that the shared index file has always been created with 600 permissions regardless of the shared permission settings. Because of that, on repositories created with `git init --shared=all` and using the split index feature, one gets an error like: fatal: .git/sharedindex.a52f910b489bc462f187ab572ba0086f7b5157de: index file open failed: Permission denied when another user performs any operation that reads the shared index. Call adjust_shared_perm() on the temporary file created by mks_tempfile() ourselves to adjust the permission bits. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-24Merge branch 'ab/free-and-null'Libravatar Junio C Hamano1-4/+2
A common pattern to free a piece of memory and assign NULL to the pointer that used to point at it has been replaced with a new FREE_AND_NULL() macro. * ab/free-and-null: *.[ch] refactoring: make use of the FREE_AND_NULL() macro coccinelle: make use of the "expression" FREE_AND_NULL() rule coccinelle: add a rule to make "expression" code use FREE_AND_NULL() coccinelle: make use of the "type" FREE_AND_NULL() rule coccinelle: add a rule to make "type" code use FREE_AND_NULL() git-compat-util: add a FREE_AND_NULL() wrapper around free(ptr); ptr = NULL
2017-06-24Merge branch 'bw/config-h'Libravatar Junio C Hamano1-0/+1
Fix configuration codepath to pay proper attention to commondir that is used in multi-worktree situation, and isolate config API into its own header file. * bw/config-h: config: don't implicitly use gitdir or commondir config: respect commondir setup: teach discover_git_directory to respect the commondir config: don't include config.h by default config: remove git_config_iter config: create config.h
2017-06-24Merge branch 'nd/split-index-unshare'Libravatar Junio C Hamano1-2/+8
* nd/split-index-unshare: Revert "split-index: add and use unshare_split_index()"
2017-06-24Revert "split-index: add and use unshare_split_index()"Libravatar Junio C Hamano1-2/+8
This reverts commit f9d7abec2ad2f9eb3d8873169cc28c34273df082; see public-inbox.org/git/CAP8UFD0bOfzY-_hBDKddOcJdPUpP2KEVaX_SrCgvAMYAHtseiQ@mail.gmail.com
2017-06-16coccinelle: make use of the "type" FREE_AND_NULL() ruleLibravatar Ævar Arnfjörð Bjarmason1-4/+2
Apply the result of the just-added coccinelle rule. This manually excludes a few occurrences, mostly things that resulted in many FREE_AND_NULL() on one line, that'll be manually fixed in a subsequent change. Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15config: don't include config.h by defaultLibravatar Brandon Williams1-0/+1
Stop including config.h by default in cache.h. Instead only include config.h in those files which require use of the config system. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-13Merge branch 'jh/close-index-before-stat' into maintLibravatar Junio C Hamano1-4/+9
The timestamp of the index file is now taken after the file is closed, to help Windows, on which a stale timestamp is reported by fstat() on a file that is opened for writing and data was written but not yet closed. * jh/close-index-before-stat: read-cache: close index.lock in do_write_index
2017-06-05Merge branch 'jh/close-index-before-stat'Libravatar Junio C Hamano1-4/+9
The timestamp of the index file is now taken after the file is closed, to help Windows, on which a stale timestamp is reported by fstat() on a file that is opened for writing and data was written but not yet closed. * jh/close-index-before-stat: read-cache: close index.lock in do_write_index
2017-05-30Merge branch 'dt/unpack-save-untracked-cache-extension'Libravatar Junio C Hamano1-0/+6
When "git checkout", "git merge", etc. manipulates the in-core index, various pieces of information in the index extensions are discarded from the original state, as it is usually not the case that they are kept up-to-date and in-sync with the operation on the main index. The untracked cache extension is copied across these operations now, which would speed up "git status" (as long as the cache is properly invalidated). * dt/unpack-save-untracked-cache-extension: unpack-trees: preserve index extensions
2017-05-29Merge branch 'nd/split-index-unshare'Libravatar Junio C Hamano1-8/+2
Plug some leaks and updates internal API used to implement the split index feature to make it easier to avoid such a leak in the future. * nd/split-index-unshare: p3400: add perf tests for rebasing many changes split-index: add and use unshare_split_index()
2017-05-20unpack-trees: preserve index extensionsLibravatar David Turner1-0/+6
Make git checkout (and other unpack_tree operations) preserve the untracked cache. This is valuable for two reasons: 1. Often, an unpack_tree operation will not touch large parts of the working tree, and thus most of the untracked cache will continue to be valid. 2. Even if the untracked cache were entirely invalidated by such an operation, the user has signaled their intention to have such a cache, and we don't want to throw it away. [jes: backed out the watchman-specific parts] Signed-off-by: David Turner <dturner@twopensource.com> Signed-off-by: Ben Peart <benpeart@microsoft.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-16Merge branch 'jk/no-null-sha1-in-cache-tree'Libravatar Junio C Hamano1-1/+4
Code to update the cache-tree has been tightened so that we won't accidentally write out any 0{40} entry in the tree object. * jk/no-null-sha1-in-cache-tree: cache-tree: reject entries with null sha1
2017-05-08split-index: add and use unshare_split_index()Libravatar Nguyễn Thái Ngọc Duy1-8/+2
When split-index is being used, we have two cache_entry arrays in index_state->cache[] and index_state->split_index->base->cache[]. index_state->cache[] may share the same entries with base->cache[] so we can quickly determine what entries are shared. This makes memory management tricky, we can't free base->cache[] until we know index_state->cache[] does not point to any of those entries. unshare_split_index() is added for this purpose, to find shared entries and either duplicate them in index_state->cache[], or discard them. Either way it should be safe to free base->cache[] after unshare_split_index(). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-01i18n: read-cache: typofixLibravatar Peter Krefting1-1/+1
Signed-off-by: Peter Krefting <peter@softwolves.pp.se> Signed-off-by: Jean-Noel Avila <jn.avila@free.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-28read-cache: close index.lock in do_write_indexLibravatar Jeff Hostetler1-4/+9
Teach do_write_index() to close the index.lock file before getting the mtime and updating the istate.timestamp fields. On Windows, a file's mtime is not updated until the file is closed. On Linux, the mtime is set after the last flush. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-26Merge branch 'cc/split-index-config'Libravatar Junio C Hamano1-1/+2
The split-index code configuration code used an unsafe git_path() function without copying its result out. * cc/split-index-config: read-cache: avoid using git_path() in freshen_shared_index()
2017-04-26Merge branch 'jh/add-index-entry-optim'Libravatar Junio C Hamano1-2/+137
"git checkout" that handles a lot of paths has been optimized by reducing the number of unnecessary checks of paths in the has_dir_name() function. * jh/add-index-entry-optim: read-cache: speed up has_dir_name (part 2) read-cache: speed up has_dir_name (part 1) read-cache: speed up add_index_entry during checkout p0006-read-tree-checkout: perf test to time read-tree read-cache: add strcmp_offset function
2017-04-23cache-tree: reject entries with null sha1Libravatar Jeff King1-1/+4
We generally disallow null sha1s from entering the index, due to 4337b5856 (do not write null sha1s to on-disk index, 2012-07-28). However, we loosened that in 83bd7437c (write_index: optionally allow broken null sha1s, 2013-08-27) so that tools like filter-branch could be used to repair broken history. However, we should make sure that these broken entries do not get propagated into new trees. For most entries, we'd catch them with the missing-object check (since presumably the null sha1 does not exist in our object database). But gitlink entries do not need reachability, so we may blindly copy the entry into a bogus tree. This patch rejects all null sha1s (with the same "invalid entry" message that missing objects get) when building trees from the index. It does so even for non-gitlinks, and even when "write-tree" is given the --missing-ok flag. The null sha1 is a special sentinel value that is already rejected in trees by fsck; whether the object exists or not, it is an error to put it in a tree. Note that for this to work, we must also avoid reusing an existing cache-tree that contains the null sha1. This patch does so by just refusing to write out any cache tree when the index contains a null sha1. This is blunter than we need to be; we could just reject the subtree that contains the offending entry. But it's not worth the complexity. The behavior is unchanged unless you have a broken index entry, and even then we'd refuse the whole index write unless the emergency GIT_ALLOW_NULL_SHA1 is in use. And even then the end result is only a performance drop (any write-tree will have to generate the whole cache-tree from scratch). The tests bear some explanation. The existing test in t7009 doesn't catch this problem, because our index-filter runs "git rm --cached", which will try to rewrite the updated index and barf on the bogus entry. So we never even make it to write-tree. The new test there adds a noop index-filter, which does show the problem. The new tests in t1601 are slightly redundant with what filter-branch is doing under the hood in t7009. But as they're much more direct, they're easier to reason about. And should filter-branch ever change or go away, we'd want to make sure that these plumbing commands behave sanely. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-20read-cache: avoid using git_path() in freshen_shared_index()Libravatar Christian Couder1-1/+2
When performing an interactive rebase in split-index mode, the commit message that one should rework when squashing commits can contain some garbage instead of the usual concatenation of both of the commit messages. The code uses git_path() to compute the shared index filename, and passes it to check_and_freshen_file() as its argument; there is no guarantee that the rotating pathname buffer passed as argument will stay valid during the life of this call. Make our own copy before calling the function and pass the copy as its argument to avoid this risky pattern. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-19read-cache: speed up has_dir_name (part 2)Libravatar Jeff Hostetler1-1/+62
Teach has_dir_name() to see if the path of the new item is greater than the last path in the index array before attempting to search for it. has_dir_name() is looking for file/directory collisions in the index and has to consider each sub-directory prefix in turn. This can cause multiple binary searches for each path. During operations like checkout, merge_working_tree() populates the new index in sorted order, so we expect to be able to append in many cases. This commit is part 2 of 2. This commit handles the additional possible short-cuts as we look at each sub-directory prefix. The net-net gains for add_index_entry_with_check() and both had_dir_name() commits are best seen for very large repos. Here are results for an INFLATED version of linux.git with 1M files. $ GIT_PERF_REPO=/mnt/test/linux_inflated.git/ ./run upstream/base HEAD ./p0006-read-tree-checkout.sh Test upstream/base HEAD 0006.2: read-tree br_base br_ballast (1043893) 3.79(3.63+0.15) 2.68(2.52+0.15) -29.3% 0006.3: switch between br_base br_ballast (1043893) 7.55(6.58+0.44) 6.03(4.60+0.43) -20.1% 0006.4: switch between br_ballast br_ballast_plus_1 (1043893) 10.84(9.26+0.59) 8.44(7.06+0.65) -22.1% 0006.5: switch between aliases (1043893) 10.93(9.39+0.58) 10.24(7.04+0.63) -6.3% Here are results for a synthetic repo with 4.2M files. $ GIT_PERF_REPO=~/work/gfw/t/perf/repos/gen-many-files-10.4.3.git/ ./run HEAD~3 HEAD ./p0006-read-tree-checkout.sh Test HEAD~3 HEAD 0006.2: read-tree br_base br_ballast (4194305) 29.96(19.26+10.50) 23.76(13.42+10.12) -20.7% 0006.3: switch between br_base br_ballast (4194305) 56.95(36.08+16.83) 45.54(25.94+15.68) -20.0% 0006.4: switch between br_ballast br_ballast_plus_1 (4194305) 90.94(51.50+31.52) 78.22(39.39+30.70) -14.0% 0006.5: switch between aliases (4194305) 93.72(51.63+34.09) 77.94(39.00+30.88) -16.8% Results for medium repos (like linux.git) are mixed and have more variance (probably do to disk IO unrelated to this test. $ GIT_PERF_REPO=/mnt/test/linux.git/ ./run HEAD~3 HEAD ./p0006-read-tree-checkout.sh Test HEAD~3 HEAD 0006.2: read-tree br_base br_ballast (57994) 0.25(0.21+0.03) 0.20(0.17+0.02) -20.0% 0006.3: switch between br_base br_ballast (57994) 10.67(6.06+2.92) 10.51(5.94+2.91) -1.5% 0006.4: switch between br_ballast br_ballast_plus_1 (57994) 0.59(0.47+0.16) 0.52(0.40+0.13) -11.9% 0006.5: switch between aliases (57994) 0.59(0.44+0.17) 0.51(0.38+0.14) -13.6% $ GIT_PERF_REPO=/mnt/test/linux.git/ ./run HEAD~3 HEAD ./p0006-read-tree-checkout.sh Test HEAD~3 HEAD 0006.2: read-tree br_base br_ballast (57994) 0.24(0.21+0.02) 0.21(0.18+0.02) -12.5% 0006.3: switch between br_base br_ballast (57994) 10.42(5.98+2.91) 10.66(5.86+3.09) +2.3% 0006.4: switch between br_ballast br_ballast_plus_1 (57994) 0.59(0.49+0.13) 0.53(0.37+0.16) -10.2% 0006.5: switch between aliases (57994) 0.59(0.43+0.17) 0.50(0.37+0.14) -15.3% Results for smaller repos (like git.git) are not significant. $ ./run HEAD~3 HEAD ./p0006-read-tree-checkout.sh Test HEAD~3 HEAD 0006.2: read-tree br_base br_ballast (3043) 0.01(0.00+0.00) 0.01(0.00+0.00) +0.0% 0006.3: switch between br_base br_ballast (3043) 0.31(0.17+0.11) 0.29(0.19+0.08) -6.5% 0006.4: switch between br_ballast br_ballast_plus_1 (3043) 0.03(0.02+0.00) 0.03(0.02+0.00) +0.0% 0006.5: switch between aliases (3043) 0.03(0.02+0.00) 0.03(0.02+0.00) +0.0% Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-19read-cache: speed up has_dir_name (part 1)Libravatar Jeff Hostetler1-0/+45
Teach has_dir_name() to see if the path of the new item is greater than the last path in the index array before attempting to search for it. has_dir_name() is looking for file/directory collisions in the index and has to consider each sub-directory prefix in turn. This can cause multiple binary searches for each path. During operations like checkout, merge_working_tree() populates the new index in sorted order, so we expect to be able to append in many cases. This commit is part 1 of 2. This commit handles the top of has_dir_name() and the trivial optimization. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-19read-cache: speed up add_index_entry during checkoutLibravatar Jeff Hostetler1-1/+10
Teach add_index_entry_with_check() to see if the path of the new item is greater than the last path in the index array before attempting to search for it. During checkout, merge_working_tree() populates the new index in sorted order, so this change will save a binary lookups per file. This preserves the original behavior but simply checks the last element before starting the search. This helps performance on very large repositories. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-15read-cache: add strcmp_offset functionLibravatar Jeff Hostetler1-0/+20
Add strcmp_offset() function to also return the offset of the first change. Add unit test and helper to verify. Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-15read-cache: force_verify_index_checksumLibravatar Jeff Hostetler1-0/+7
Teach git to skip verification of the SHA1-1 checksum at the end of the index file in verify_hdr() which is called from read_index() unless the "force_verify_index_checksum" global variable is set. Teach fsck to force this verification. The checksum verification is for detecting disk corruption, and for small projects, the time it takes to compute SHA-1 is not that significant, but for gigantic repositories this calculation adds significant time to every command. These effect can be seen using t/perf/p0002-read-cache.sh: Test HEAD~1 HEAD -------------------------------------------------------------------------------------- 0002.1: read_cache/discard_cache 1000 times 0.66(0.44+0.20) 0.30(0.27+0.02) -54.5% Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-17Merge branch 'cc/split-index-config'Libravatar Junio C Hamano1-10/+147
The experimental "split index" feature has gained a few configuration variables to make it easier to use. * cc/split-index-config: (22 commits) Documentation/git-update-index: explain splitIndex.* Documentation/config: add splitIndex.sharedIndexExpire read-cache: use freshen_shared_index() in read_index_from() read-cache: refactor read_index_from() t1700: test shared index file expiration read-cache: unlink old sharedindex files config: add git_config_get_expiry() from gc.c read-cache: touch shared index files when used sha1_file: make check_and_freshen_file() non static Documentation/config: add splitIndex.maxPercentChange t1700: add tests for splitIndex.maxPercentChange read-cache: regenerate shared index if necessary config: add git_config_get_max_percent_split_change() Documentation/git-update-index: talk about core.splitIndex config var Documentation/config: add information for core.splitIndex t1700: add tests for core.splitIndex update-index: warn in case of split-index incoherency read-cache: add and then use tweak_split_index() split-index: add {add,remove}_split_index() functions config: add git_config_get_split_index() ...
2017-03-06read-cache: use freshen_shared_index() in read_index_from()Libravatar Christian Couder1-0/+1
This way a share index file will not be garbage collected if we still read from an index it is based from. As we need to read the current index before creating a new one, the tests have to be adjusted, so that we don't expect an old shared index file to be deleted right away when we create a new one. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-06read-cache: refactor read_index_from()Libravatar Christian Couder1-6/+8
It looks better and is simpler to review when we don't compute the same things many times in the function. It will also help make the following commit simpler. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-06read-cache: unlink old sharedindex filesLibravatar Christian Couder1-1/+63
Everytime split index is turned on, it creates a "sharedindex.XXXX" file in the git directory. This change makes sure that shared index files that haven't been used for a long time are removed when a new shared index file is created. The new "splitIndex.sharedIndexExpire" config variable is created to tell the delay after which an unused shared index file can be deleted. It defaults to "2.weeks.ago". A previous commit made sure that each time a split index file is created the mtime of the shared index file it references is updated. This makes sure that recently used shared index file will not be deleted. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-01read-cache: touch shared index files when usedLibravatar Christian Couder1-3/+26
When a split-index file is created, let's update the mtime of the shared index file that the split-index file is referencing. In a following commit we will make shared index file expire depending on their mtime, so updating the mtime makes sure that the shared index file will not be deleted soon. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-01read-cache: regenerate shared index if necessaryLibravatar Christian Couder1-0/+32
When writing a new split-index and there is a big number of cache entries in the split-index compared to the shared index, it is a good idea to regenerate the shared index. By default when the ratio reaches 20%, we will push back all the entries from the split-index into a new shared index file instead of just creating a new split-index file. The threshold can be configured using the "splitIndex.maxPercentChange" config variable. We need to adjust the existing tests in t1700 by setting "splitIndex.maxPercentChange" to 100 at the beginning of t1700, as the existing tests are assuming that the shared index is regenerated only when `git update-index --split-index` is used. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-01read-cache: add and then use tweak_split_index()Libravatar Christian Couder1-0/+17
This will make us use the split-index feature or not depending on the value of the "core.splitIndex" config variable. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-31Merge branch 'sb/in-core-index-doc'Libravatar Junio C Hamano1-1/+0
Documentation and in-code comments updates. * sb/in-core-index-doc: documentation: retire unfinished documentation cache.h: document add_[file_]to_index cache.h: document remove_index_entry_at cache.h: document index_name_pos
2017-01-19cache.h: document remove_index_entry_atLibravatar Stefan Beller1-1/+0
Do this by moving the existing documentation from read-cache.c to cache.h. Signed-off-by: Stefan Beller <sbeller@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-11index: improve constness for reading blob dataLibravatar Brandon Williams1-1/+2
Improve constness of the index_state parameter to the 'read_blob_data_from_index' function. Signed-off-by: Brandon Williams <bmwill@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-01-10Merge branch 'jc/git-open-cloexec'Libravatar Junio C Hamano1-8/+1
The codeflow of setting NOATIME and CLOEXEC on file descriptors Git opens has been simplified. We may want to drop the tip one, but we'll see. * jc/git-open-cloexec: sha1_file: stop opening files with O_NOATIME git_open_cloexec(): use fcntl(2) w/ FD_CLOEXEC fallback git_open(): untangle possible NOATIME and CLOEXEC interactions
2016-12-07hold_locked_index(): align error handling with hold_lockfile_for_update()Libravatar Junio C Hamano1-5/+2
Callers of the hold_locked_index() function pass 0 when they want to prepare to write a new version of the index file without wishing to die or emit an error message when the request fails (e.g. somebody else already held the lock), and pass 1 when they want the call to die upon failure. This option is called LOCK_DIE_ON_ERROR by the underlying lockfile API, and the hold_locked_index() function translates the paramter to LOCK_DIE_ON_ERROR when calling the hold_lock_file_for_update(). Replace these hardcoded '1' with LOCK_DIE_ON_ERROR and stop translating. Callers other than the ones that are replaced with this change pass '0' to the function; no behaviour change is intended with this patch. Signed-off-by: Junio C Hamano <gitster@pobox.com> --- Among the callers of hold_locked_index() that passes 0: - diff.c::refresh_index_quietly() at the end of "git diff" is an opportunistic update; it leaks the lockfile structure but it is just before the program exits and nobody should care. - builtin/describe.c::cmd_describe(), builtin/commit.c::cmd_status(), sequencer.c::read_and_refresh_cache() are all opportunistic updates and they are OK. - builtin/update-index.c::cmd_update_index() takes a lock upfront but we may end up not needing to update the index (i.e. the entries may be fully up-to-date), in which case we do not need to issue an error upon failure to acquire the lock. We do diagnose and die if we indeed need to update, so it is OK. - wt-status.c::require_clean_work_tree() IS BUGGY. It asks silence, does not check the returned value. Compare with callsites like cmd_describe() and cmd_status() to notice that it is wrong to call update_index_if_able() unconditionally.
2016-10-28git_open(): untangle possible NOATIME and CLOEXEC interactionsLibravatar Junio C Hamano1-8/+1
The way we structured the fallback/retry mechanism for opening with O_NOATIME and O_CLOEXEC meant that if we failed due to lack of support to open the file with O_NOATIME option (i.e. EINVAL), we would still try to drop O_CLOEXEC first and retry, and then drop O_NOATIME. A platform on which O_NOATIME is defined in the header without support from the kernel wouldn't have a chance to open with O_CLOEXEC option due to this code structure. Arguably, O_CLOEXEC is more important than O_NOATIME, as the latter is mostly about performance, while the former can affect correctness. Instead use O_CLOEXEC to open the file, and then use fcntl(2) to set O_NOATIME on the resulting file descriptor. open(2) itself does not cause atime to be updated according to Linus [*1*]. The helper to do the former can be usable in the codepath in ce_compare_data() that was recently added to open a file descriptor with O_CLOEXEC; use it while we are at it. *1* <CA+55aFw83E+zOd+z5h-CA-3NhrLjVr-anL6pubrSWttYx3zu8g@mail.gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-10-25read-cache: make sure file handles are not inherited by child processesLibravatar Lars Schneider1-1/+8
This fixes "convert: add filter.<driver>.process option" (edcc8581) on Windows. Consider the case of a file that requires filtering and is present in branch A but not in branch B. If A is the current HEAD and we checkout B then the following happens: 1. ce_compare_data() opens the file 2. index_fd() detects that the file requires to run a clean filter and calls index_stream_convert_blob() 4. index_stream_convert_blob() calls convert_to_git_filter_fd() 5. convert_to_git_filter_fd() calls apply_filter() which creates a new long running filter process (in case it is the first file of this kind to be filtered) 6. The new filter process inherits all file handles. This is the default on Linux/OSX and is explicitly defined in the `CreateProcessW` call in `mingw.c` on Windows. 7. ce_compare_data() closes the file 8. Git unlinks the file as it is not present in B The unlink operation does not work on Windows because the filter process has still an open handle to the file. On Linux/OSX the unlink operation succeeds but the file descriptors still leak into the child process. Fix this problem by opening files in read-cache with the O_CLOEXEC flag to ensure that the file descriptor does not remain open in a newly spawned process similar to 05d1ed6148 ("mingw: ensure temporary file handles are not inherited by child processes", 2016-08-22). Signed-off-by: Lars Schneider <larsxschneider@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-09-26Merge branch 'tg/add-chmod+x-fix'Libravatar Junio C Hamano1-8/+35
"git add --chmod=+x <pathspec>" added recently only toggled the executable bit for paths that are either new or modified. This has been corrected to flip the executable bit for all paths that match the given pathspec. * tg/add-chmod+x-fix: t3700-add: do not check working tree file mode without POSIXPERM t3700-add: create subdirectory gently add: modify already added files when --chmod is given read-cache: introduce chmod_index_entry update-index: add test for chmod flags