This function will be used in the next commit to prevent
`setup_git_directory()` from discovering a repository in a directory
that is owned by someone other than the current user.
Note: We cannot simply use `st.st_uid` on Windows just like we do on
Linux and other Unix-like platforms: according to
https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/stat-functions
this field is always zero on Windows (because Windows' idea of a user ID
does not fit into a single numerical value). Therefore, we have to do
something a little involved to replicate the same functionality there.
Also note: On Windows, a user's home directory is not actually owned by
said user, but by the administrator. For all practical purposes, it is
under the user's control, though, therefore we pretend that it is owned
by the user.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
mingw-w64's pthread_unistd.h had a bug that mistakenly (because there is
no support for the *lockfile() functions required[1]) defined
_POSIX_THREAD_SAFE_FUNCTIONS and that was being worked around since
3ecd153a3b (compat/mingw: support MSys2-based MinGW build, 2016-01-14).
The bug was fixed in winphtreads, but as a side effect, leaves the
reentrant functions from time.h no longer visible and therefore breaks
the build.
Since the intention all along was to avoid using the fallback functions,
formalize the use of POSIX by setting the corresponding feature flag and
compile out the implementation for the fallback functions.
[1] https://unix.org/whitepapers/reentrant.html
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Acked-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint-2.22:
Git 2.22.5
Git 2.21.4
Git 2.20.5
Git 2.19.6
Git 2.18.5
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
* maint-2.21:
Git 2.21.4
Git 2.20.5
Git 2.19.6
Git 2.18.5
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
* maint-2.20:
Git 2.20.5
Git 2.19.6
Git 2.18.5
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
* maint-2.19:
Git 2.19.6
Git 2.18.5
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
* maint-2.18:
Git 2.18.5
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
* maint-2.17:
Git 2.17.6
unpack_trees(): start with a fresh lstat cache
run-command: invalidate lstat cache after a command finished
checkout: fix bug that makes checkout follow symlinks in leading path
Before checking out a file, we have to confirm that all of its leading
components are real existing directories. And to reduce the number of
lstat() calls in this process, we cache the last leading path known to
contain only directories. However, when a path collision occurs (e.g.
when checking out case-sensitive files in case-insensitive file
systems), a cached path might have its file type changed on disk,
leaving the cache on an invalid state. Normally, this doesn't bring
any bad consequences as we usually check out files in index order, and
therefore, by the time the cached path becomes outdated, we no longer
need it anyway (because all files in that directory would have already
been written).
But, there are some users of the checkout machinery that do not always
follow the index order. In particular: checkout-index writes the paths
in the same order that they appear on the CLI (or stdin); and the
delayed checkout feature -- used when a long-running filter process
replies with "status=delayed" -- postpones the checkout of some entries,
thus modifying the checkout order.
When we have to check out an out-of-order entry and the lstat() cache is
invalid (due to a previous path collision), checkout_entry() may end up
using the invalid data and thrusting that the leading components are
real directories when, in reality, they are not. In the best case
scenario, where the directory was replaced by a regular file, the user
will get an error: "fatal: unable to create file 'foo/bar': Not a
directory". But if the directory was replaced by a symlink, checkout
could actually end up following the symlink and writing the file at a
wrong place, even outside the repository. Since delayed checkout is
affected by this bug, it could be used by an attacker to write
arbitrary files during the clone of a maliciously crafted repository.
Some candidate solutions considered were to disable the lstat() cache
during unordered checkouts or sort the entries before passing them to
the checkout machinery. But both ideas include some performance penalty
and they don't future-proof the code against new unordered use cases.
Instead, we now manually reset the lstat cache whenever we successfully
remove a directory. Note: We are not even checking whether the directory
was the same as the lstat cache points to because we might face a
scenario where the paths refer to the same location but differ due to
case folding, precomposed UTF-8 issues, or the presence of `..`
components in the path. Two regression tests, with case-collisions and
utf8-collisions, are also added for both checkout-index and delayed
checkout.
Note: to make the previously mentioned clone attack unfeasible, it would
be sufficient to reset the lstat cache only after the remove_subtree()
call inside checkout_entry(). This is the place where we would remove a
directory whose path collides with the path of another entry that we are
currently trying to check out (possibly a symlink). However, in the
interest of a thorough fix that does not leave Git open to
similar-but-not-identical attack vectors, we decided to intercept
all `rmdir()` calls in one fell swoop.
This addresses CVE-2021-21300.
Co-authored-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Matheus Tavares <matheus.bernardino@usp.br>
When 15b52a44 (compat-util: type-check parameters of no-op
replacement functions, 2020-08-06) turned a handful of no-op
C-preprocessor macros into static inline functions to give the
callers a better type checking for their parameters, it forgot
to return anything from the stubbed out setitimer() function,
even though the function was defined to return an int just like the
real thing.
Since the original C-preprocessor macro implementation was to just
turn the call to the function an empty statement, we know that the
existing callers do not check the return value from it, and it does
not matter what value we return. But it is safer to pretend that
the call succeeded by returning 0 than making it fail by returning -1
and clobbering errno with some value.
Reported-by: Randall S. Becker <rsbecker@nexbridge.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The sleep function is defined in wrapper.c, so it makes more sense to be a in
system compatibility header.
Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The usage, die, warning, and error routines all work with a function
pointer that takes the message to be reported. We usually just mention
the function's full type inline. But this makes the use of these
pointers hard to read, especially because C's syntax for returning a
function pointer is so awful:
void (*get_error_routine(void))(const char *err, va_list params);
Unless you read it very carefully, this looks like a function pointer
declaration. Let's instead use a single typedef to define a reporting
function, which is the same for all four types.
Note that this also removes the "extern" from these declarations to
match the surrounding functions. They were missed in 554544276a (*.[ch]:
remove extern from function declarations using spatch, 2019-04-29)
presumably because of the unusual syntax.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When there is no need to run a specific function on certain platforms,
we often #define an empty function to swallow its parameters and
make it into a no-op, e.g.
#define precompose_argv(c,v) /* no-op */
While this guarantees that no unneeded code is generated, it also
discards type and other checks on these parameters, e.g. a new code
written with the argv-array API (diff_args is of type "struct
argv_array" that has .argc and .argv members):
precompose_argv(diff_args.argc, diff_args.argv);
must be updated to use "struct strvec diff_args" with .nr and .v
members, like so:
precompose_argv(diff_args.nr, diff_args.v);
after the argv-array API has been updated to the strvec API.
However, the "no oop" C preprocessor macro is too aggressive to
discard what is unused, and did not catch such a call that was left
unconverted.
Using a "static inline" function whose body is a no-op should still
result in the same binary with decent compilers yet catch such a
reference to a missing field or passing a value of a wrong type.
While at it, I notice that precompute_str() has never been used
anywhere in the code, since it was introduced at 76759c7d (git on
Mac OS and precomposed unicode, 2012-07-08). Instead of turning it
into a static inline, just remove it.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
SHA-256 migration work continues.
* bc/sha-256-part-2: (44 commits)
remote-testgit: adapt for object-format
bundle: detect hash algorithm when reading refs
t5300: pass --object-format to git index-pack
t5704: send object-format capability with SHA-256
t5703: use object-format serve option
t5702: offer an object-format capability in the test
t/helper: initialize the repository for test-sha1-array
remote-curl: avoid truncating refs with ls-remote
t1050: pass algorithm to index-pack when outside repo
builtin/index-pack: add option to specify hash algorithm
remote-curl: detect algorithm for dumb HTTP by size
builtin/ls-remote: initialize repository based on fetch
t5500: make hash independent
serve: advertise object-format capability for protocol v2
connect: parse v2 refs with correct hash algorithm
connect: pass full packet reader when parsing v2 refs
Documentation/technical: document object-format for protocol v2
t1302: expect repo format version 1 for SHA-256
builtin/show-index: provide options to determine hash algo
t5302: modernize test formatting
...
When parsing capabilities for the pack protocol, there are times we'll
want to compare the value of a capability to a NUL-terminated string.
Since the data we're reading will be space-terminated, not
NUL-terminated, we need a function that compares the two strings, but
also checks that they're the same length. Otherwise, if we used strncmp
to compare these strings, we might accidentally accept a parameter that
was a prefix of the expected value.
Add a function, xstrncmpz, that takes a NUL-terminated string and a
non-NUL-terminated string, plus a length, and compares them, ensuring
that they are the same length.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
ccd469450a (date.c: switch to reentrant {gm,local}time_r, 2019-11-28)
removes the only gmtime() call we had and moves to gmtime_r() which
doesn't have the same portability problems.
Remove the compat gmtime code since it is no longer needed, and confirm
by successfull running t4212 in FreeBSD 9.3 amd64 (the oldest I could
get a hold off).
Further work might be needed to ensure 32bit time_t systems (like FreeBSD
i386) will handle correctly the overflows tested in t4212, but that is
orthogonal to this change, and it doesn't change the current behaviour
as neither gmtime() or gmtime_r() will ever return NULL on those systems
because time_t is unsigned.
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
On Cygwin, the codepath for POSIX-like systems is taken in
run-command.c::start_command(). The prepare_cmd() helper
function is called to decide if the command needs to be looked
up in the PATH. The logic there is to do the PATH-lookup if
and only if it does not have any slash '/' in it. If this test
passes we end up attempting to run the command by appending the
string after each colon-separated component of PATH.
The Cygwin environment supports both Windows and POSIX style
paths, so both forwardslahes '/' and back slashes '\' can be
used as directory separators for any external program the user
supplies.
Examples for path strings which are being incorrectly searched
for in the PATH instead of being executed as is:
- "C:\Program Files\some-program.exe"
- "a\b\c.exe"
To handle these, the PATH lookup detection logic in prepare_cmd()
is taught to know about this Cygwin quirk, by introducing
has_dir_sep(path) helper function to abstract away the difference
between true POSIX and Cygwin systems.
Signed-off-by: Andras Kucsma <r0maikx02b@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* maint-2.23: (44 commits)
Git 2.23.1
Git 2.22.2
Git 2.21.1
mingw: sh arguments need quoting in more circumstances
mingw: fix quoting of empty arguments for `sh`
mingw: use MSYS2 quoting even when spawning shell scripts
mingw: detect when MSYS2's sh is to be spawned more robustly
t7415: drop v2.20.x-specific work-around
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
...
* maint-2.22: (43 commits)
Git 2.22.2
Git 2.21.1
mingw: sh arguments need quoting in more circumstances
mingw: fix quoting of empty arguments for `sh`
mingw: use MSYS2 quoting even when spawning shell scripts
mingw: detect when MSYS2's sh is to be spawned more robustly
t7415: drop v2.20.x-specific work-around
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
...
* maint-2.21: (42 commits)
Git 2.21.1
mingw: sh arguments need quoting in more circumstances
mingw: fix quoting of empty arguments for `sh`
mingw: use MSYS2 quoting even when spawning shell scripts
mingw: detect when MSYS2's sh is to be spawned more robustly
t7415: drop v2.20.x-specific work-around
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
...
* maint-2.20: (36 commits)
Git 2.20.2
t7415: adjust test for dubiously-nested submodule gitdirs for v2.20.x
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
...
* maint-2.19: (34 commits)
Git 2.19.3
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
...
* maint-2.18: (33 commits)
Git 2.18.2
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
...
* maint-2.17: (32 commits)
Git 2.17.3
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
...
* maint-2.16: (31 commits)
Git 2.16.6
test-drop-caches: use `has_dos_drive_prefix()`
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
path: safeguard `.git` against NTFS Alternate Streams Accesses
...
* maint-2.15: (29 commits)
Git 2.15.4
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
path: safeguard `.git` against NTFS Alternate Streams Accesses
clone --recurse-submodules: prevent name squatting on Windows
is_ntfs_dotgit(): only verify the leading segment
...
* maint-2.14: (28 commits)
Git 2.14.6
mingw: handle `subst`-ed "DOS drives"
mingw: refuse to access paths with trailing spaces or periods
mingw: refuse to access paths with illegal characters
unpack-trees: let merged_entry() pass through do_add_entry()'s errors
quote-stress-test: offer to test quoting arguments for MSYS2 sh
t6130/t9350: prepare for stringent Win32 path validation
quote-stress-test: allow skipping some trials
quote-stress-test: accept arguments to test via the command-line
tests: add a helper to stress test argument quoting
mingw: fix quoting of arguments
Disallow dubiously-nested submodule git directories
protect_ntfs: turn on NTFS protection by default
path: also guard `.gitmodules` against NTFS Alternate Data Streams
is_ntfs_dotgit(): speed it up
mingw: disallow backslash characters in tree objects' file names
path: safeguard `.git` against NTFS Alternate Streams Accesses
clone --recurse-submodules: prevent name squatting on Windows
is_ntfs_dotgit(): only verify the leading segment
test-path-utils: offer to run a protectNTFS/protectHFS benchmark
...
When creating a directory on Windows whose path ends in a space or a
period (or chains thereof), the Win32 API "helpfully" trims those. For
example, `mkdir("abc ");` will return success, but actually create a
directory called `abc` instead.
This stems back to the DOS days, when all file names had exactly 8
characters plus exactly 3 characters for the file extension, and the
only way to have shorter names was by padding with spaces.
Sadly, this "helpful" behavior is a bit inconsistent: after a successful
`mkdir("abc ");`, a `mkdir("abc /def")` will actually _fail_ (because
the directory `abc ` does not actually exist).
Even if it would work, we now have a serious problem because a Git
repository could contain directories `abc` and `abc `, and on Windows,
they would be "merged" unintentionally.
As these paths are illegal on Windows, anyway, let's disallow any
accesses to such paths on that Operating System.
For practical reasons, this behavior is still guarded by the
config setting `core.protectNTFS`: it is possible (and at least two
regression tests make use of it) to create commits without involving the
worktree. In such a scenario, it is of course possible -- even on
Windows -- to create such file names.
Among other consequences, this patch disallows submodules' paths to end
in spaces on Windows (which would formerly have confused Git enough to
try to write into incorrect paths, anyway).
While this patch does not fix a vulnerability on its own, it prevents an
attack vector that was exploited in demonstrations of a number of
recently-fixed security bugs.
The regression test added to `t/t7417-submodule-path-url.sh` reflects
that attack vector.
Note that we have to adjust the test case "prevent git~1 squatting on
Windows" in `t/t7415-submodule-names.sh` because of a very subtle issue.
It tries to clone two submodules whose names differ only in a trailing
period character, and as a consequence their git directories differ in
the same way. Previously, when Git tried to clone the second submodule,
it thought that the git directory already existed (because on Windows,
when you create a directory with the name `b.` it actually creates `b`),
but with this patch, the first submodule's clone will fail because of
the illegal name of the git directory. Therefore, when cloning the
second submodule, Git will take a different code path: a fresh clone
(without an existing git directory). Both code paths fail to clone the
second submodule, both because the the corresponding worktree directory
exists and is not empty, but the error messages are worded differently.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git's code base already seems to be using `PRIdMAX` without any such
fallback definition for quite a while (75459410ed (json_writer: new
routines to create JSON data, 2018-07-13), to be precise, and the
first Git version to include that commit was v2.19.0). Having a
fallback definition only for `PRIuMAX` is a bit inconsistent.
We do sometimes get portability reports more than a year after the
problem was introduced. This one should be fairly safe. PRIuMAX is
in C99 (for that matter, SCNuMAX, PRIu32 and others also are), and
we've been picking up other C99-isms without complaint.
The PRIuMAX fallback definition was originally added in 3efb1f343a
(Check for PRIuMAX rather than NO_C99_FORMAT in fast-import.c.,
2007-02-20). But it was replacing a construct that was introduced in
an even earlier commit, 579d1fbfaf (Add NO_C99_FORMAT to support
older compilers., 2006-07-30), which talks about gcc 2.95.
That's pretty ancient at this point.
Signed-off-by: Hariom Verma <hariom18599@gmail.com>
Helped-by: Jeff King <peff@peff.net>
[jc: tweaked both message and code, taking what peff wrote]
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The parameter marker for x was garbled in its introduction in 89c855ed3c
("git-compat-util.h: implement a different ARRAY_SIZE macro for for
safely deriving the size of array", 2015-04-30).
Signed-off-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The rename detection logic sorts a list of rename source candidates
by similarity to pick the best candidate, which means that a tie
between sources with the same similarity is broken by the original
location in the original candidate list (which is sorted by path).
Force the sorting by similarity done with a stable sort, which is
not promised by system supplied qsort(3), to ensure consistent
results across platforms.
* js/diff-rename-force-stable-sort:
diffcore_rename(): use a stable sort
Move git_sort(), a stable sort, into into libgit.a
While we cannot rely on a `__typeof__' operator being portable
to use with `offsetof'; we can calculate the pointer offset
using an existing pointer and the address of a member using
pointer arithmetic for compilers without `__typeof__'.
This allows us to simplify usage of hashmap iterator macros
by not having to specify a type when a pointer of that type
is already given.
In the future, list iterator macros (e.g. list_for_each_entry)
may also be implemented using OFFSETOF_VAR to save hackers the
trouble of using container_of/list_entry macros and without
relying on non-portable `__typeof__'.
v3: use `__typeof__' to avoid clang warnings
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Using `container_of' can be verbose and choosing names for
intermediate "struct hashmap_entry" pointers is a hard problem.
So introduce "*_entry" APIs inspired by similar linked-list
APIs in the Linux kernel.
Unfortunately, `__typeof__' is not portable C, so we need an
extra parameter to specify the type.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This macro is popular within the Linux kernel for supporting
intrusive data structures such as linked lists, red-black trees,
and chained hash tables while allowing the compiler to do
type checking.
Later patches will use container_of() to remove the limitation
of "hashmap_entry" being location-dependent. This will complete
the transition to compile-time type checking for the hashmap API.
This macro already exists in our source as "list_entry" in
list.h and making "list_entry" an alias to "container_of"
as the Linux kernel has done is a possibility.
Signed-off-by: Eric Wong <e@80x24.org>
Reviewed-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `qsort()` function is not guaranteed to be stable, i.e. it does not
promise to maintain the order of items it is told to consider equal. In
contrast, the `git_sort()` function we carry in `compat/qsort.c` _is_
stable, by virtue of implementing a merge sort algorithm.
In preparation for using a stable sort in Git's rename detection, move
the stable sort into `libgit.a` so that it is compiled in
unconditionally, and rename it to `git_stable_qsort()`.
Note: this also makes the hack obsolete that was introduced in
fe21c6b285 (mingw: reencode environment variables on the fly (UTF-16
<-> UTF-8), 2018-10-30), where we included `compat/qsort.c` directly in
`compat/mingw.c` to use the stable sort.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When 'git name-rev' is invoked with commit-ish parameters, it tries to
save some work, and doesn't visit commits older than the committer
date of the oldest given commit minus a one day worth of slop. Since
our 'timestamp_t' is an unsigned type, this leads to a timestamp
underflow when the committer date of the oldest given commit is within
a day of the UNIX epoch. As a result the cutoff timestamp ends up
far-far in the future, and 'git name-rev' doesn't visit any commits,
and names each given commit as 'undefined'.
Check whether subtracting the slop from the oldest committer date
would lead to an underflow, and use no cutoff in that case. We don't
have a TIME_MIN constant, dddbad728c (timestamp_t: a new data type for
timestamps, 2017-04-26) didn't add one, so do it now.
Note that the type of the cutoff timestamp variable used to be signed
before 5589e87fd8 (name-rev: change a "long" variable to timestamp_t,
2017-05-20). The behavior was still the same even back then, but the
underflow didn't happen when substracting the slop from the oldest
committer date, but when comparing the signed cutoff timestamp with
unsigned committer dates in name_rev(). IOW, this underflow bug is as
old as 'git name-rev' itself.
Helped-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
