The winsock2 library provides functions that work on different data
types than file descriptors, therefore we wrap them.
But that is not the only difference: they also do not set `errno` but
expect the callers to enquire about errors via `WSAGetLastError()`.
Let's translate that into appropriate `errno` values whenever the socket
operations fail so that Git's code base does not have to change its
expectations.
This closes https://github.com/git-for-windows/git/issues/2404
Helped-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Since commit 0c499ea60f (send-pack: demultiplex a sideband stream with
status data, 2010-02-05) the send-pack builtin uses the side-band-64k
capability if advertised by the server.
Unfortunately this breaks pushing over the dump git protocol if used
over a network connection.
The detailed reasons for this breakage are (by courtesy of Jeff Preshing,
quoted from https://groups.google.com/d/msg/msysgit/at8D7J-h7mw/eaLujILGUWoJ):
MinGW wraps Windows sockets in CRT file descriptors in order to
mimic the functionality of POSIX sockets. This causes msvcrt.dll
to treat sockets as Installable File System (IFS) handles,
calling ReadFile, WriteFile, DuplicateHandle and CloseHandle on
them. This approach works well in simple cases on recent
versions of Windows, but does not support all usage patterns. In
particular, using this approach, any attempt to read & write
concurrently on the same socket (from one or more processes)
will deadlock in a scenario where the read waits for a response
from the server which is only invoked after the write. This is
what send_pack currently attempts to do in the use_sideband
codepath.
The new config option `sendpack.sideband` allows to override the
side-band-64k capability of the server, and thus makes the dumb git
protocol work.
Other transportation methods like ssh and http/https still benefit from
the sideband channel, therefore the default value of `sendpack.sideband`
is still true.
Signed-off-by: Thomas Braun <thomas.braun@byte-physics.de>
Signed-off-by: Oliver Schneider <oliver@assarbad.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Some platforms (e.g. Windows) provide API functions to resolve paths
much quicker. Let's offer a way to short-cut `strbuf_realpath()` on
those platforms.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
NTFS junctions are somewhat similar in spirit to Unix bind mounts: they
point to a different directory and are resolved by the filesystem
driver. As such, they appear to `lstat()` as if they are directories,
not as if they are symbolic links.
_Any_ user can create junctions, while symbolic links can only be
created by non-administrators in Developer Mode on Windows 10. Hence
NTFS junctions are much more common "in the wild" than NTFS symbolic
links.
It was reported in https://github.com/git-for-windows/git/issues/2481
that adding files via an absolute path that traverses an NTFS junction:
since 1e64d18 (mingw: do resolve symlinks in `getcwd()`), we resolve not
only symbolic links but also NTFS junctions when determining the
absolute path of the current directory. The same is not true for `git
add <file>`, where symbolic links are resolved in `<file>`, but not NTFS
junctions.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Thorough benchmarking with repacking a subset of linux.git (the commit
history reachable from 93a6fefe2f ([PATCH] fix the SYSCTL=n compilation,
2007-02-28), to be precise) suggest that this allocator is on par, in
multi-threaded situations maybe even better than nedmalloc:
`git repack -adfq` with mimalloc, 8 threads:
31.166991900 27.576763800 28.712311000 27.373859000 27.163141900
`git repack -adfq` with nedmalloc, 8 threads:
31.915032900 27.149883100 28.244933700 27.240188800 28.580849500
In a different test using GitHub Actions build agents (probably
single-threaded, a core-strength of nedmalloc)):
`git repack -q -d -l -A --unpack-unreachable=2.weeks.ago` with mimalloc:
943.426 978.500 939.709 959.811 954.605
`git repack -q -d -l -A --unpack-unreachable=2.weeks.ago` with nedmalloc:
995.383 952.179 943.253 963.043 980.468
While these measurements were not executed with complete scientific
rigor, as no hardware was set aside specifically for these benchmarks,
it shows that mimalloc and nedmalloc perform almost the same, nedmalloc
with a bit higher variance and also slightly higher average (further
testing suggests that nedmalloc performs worse in multi-threaded
situations than in single-threaded ones).
In short: mimalloc seems to be slightly better suited for our purposes
than nedmalloc.
Seeing that mimalloc is developed actively, while nedmalloc ceased to
see any updates in eight years, let's use mimalloc on Windows instead.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Always use the internal "use_weak" random seed when initializing
the "mimalloc" heap when statically linked on Windows.
The imported "mimalloc" routines support several random sources
to seed the heap data structures, including BCrypt.dll and
RtlGenRandom. Crashes have been reported when using BCrypt.dll
if it initialized during an `atexit()` handler function. Granted,
such DLL initialization should not happen in an atexit handler,
but yet the crashes remain.
It should be noted that on Windows when statically linked, the
mimalloc startup code (called by the GCC CRT to initialize static
data prior to calling `main()`) always uses the internal "weak"
random seed. "mimalloc" does not try to load an alternate
random source until after the OS initialization has completed.
Heap data is stored in `__declspec(thread)` TLS data and in theory
each Git thread will have its own heap data. However, testing
shows that the "mimalloc" library doesn't actually call
`os_random_buf()` (to load a new random source) when creating these
new per-thread heap structures.
However, if an atexit handler is forced to run on a non-main
thread, the "mimalloc" library *WILL* try to create a new heap
and seed it with `os_random_buf()`. (The reason for this is still
a mystery to this author.) The `os_random_buf()` call can cause
the (previously uninitialized BCrypt.dll library) to be dynamically
loaded and a call made into it. Crashes have been reported in
v2.40.1.vfs.0.0 while in this call.
As a workaround, the fix here forces the use of the internal
"use_weak" random code for the subsequent `os_random_buf()` calls.
Since we have been using that random generator for the majority
of the program, it seems safe to use it for the final few mallocs
in the atexit handler (of which there really shouldn't be that many.
Signed-off-by: Jeff Hostetler <jeffhostetler@github.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
By defining `USE_MIMALLOC`, Git can now be compiled with that
nicely-fast and small allocator.
Note that we have to disable a couple `DEVELOPER` options to build
mimalloc's source code, as it makes heavy use of declarations after
statements, among other things that disagree with Git's conventions.
We even have to silence some GCC warnings in non-DEVELOPER mode. For
example, the `-Wno-array-bounds` flag is needed because in `-O2` builds,
trying to call `NtCurrentTeb()` (which `_mi_thread_id()` does on
Windows) causes the bogus warning about a system header, likely related
to https://sourceforge.net/p/mingw-w64/mailman/message/37674519/ and to
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99578:
C:/git-sdk-64-minimal/mingw64/include/psdk_inc/intrin-impl.h:838:1:
error: array subscript 0 is outside array bounds of 'long long unsigned int[0]' [-Werror=array-bounds]
838 | __buildreadseg(__readgsqword, unsigned __int64, "gs", "q")
| ^~~~~~~~~~~~~~
Also: The `mimalloc` library uses C11-style atomics, therefore we must
require that standard when compiling with GCC if we want to use
`mimalloc` (instead of requiring "only" C99). This is what we do in the
CMake definition already, therefore this commit does not need to touch
`contrib/buildsystems/`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We want to compile mimalloc's source code as part of Git, rather than
requiring the code to be built as an external library: mimalloc uses a
CMake-based build, which is not necessarily easy to integrate into the
flavors of Git for Windows (which will be the main benefitting port).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This commit imports mimalloc's source code as per v2.0.9, fetched from
the tag at https://github.com/microsoft/mimalloc.
The .c files are from the src/ subdirectory, and the .h files from the
include/ subdirectory. We will subsequently modify the source code to
accommodate building within Git's context.
Since we plan on using the `mi_*()` family of functions, we skip the
C++-specific source code, some POSIX compliant functions to interact
with mimalloc, and the code that wants to support auto-magic overriding
of the `malloc()` function (mimalloc-new-delete.h, alloc-posix.c,
mimalloc-override.h, alloc-override.c, alloc-override-osx.c,
alloc-override-win.c and static.c).
To appease the `check-whitespace` job of Git's Continuous Integration,
this commit was washed one time via `git rebase --whitespace=fix`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We are about to vendor in `mimalloc`'s source code which we will want to
include `git-compat-util.h` after defining that constant.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The mingw-w64 GCC seems to link implicitly to libwinpthread, which does
implement a pthread emulation (that is more complete than Git's). Let's
keep preferring Git's.
To avoid linker errors where it thinks that the `pthread_self` and the
`pthread_create` symbols are defined twice, let's give our version a
`win32_` prefix, just like we already do for `pthread_join()`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
While Git for Windows does not _ship_ Python (in order to save on
bandwidth), MSYS2 provides very fine Python interpreters that users can
easily take advantage of, by using Git for Windows within its SDK.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Windows' equivalent to "bind mounts", NTFS junction points, can be
unlinked without affecting the mount target. This is clearly what users
expect to happen when they call `git clean -dfx` in a worktree that
contains NTFS junction points: the junction should be removed, and the
target directory of said junction should be left alone (unless it is
inside the worktree).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When specifying an absolute path without a drive prefix, we convert that
path internally. Let's make sure that we handle that case properly, too
;-)
This fixes the command
git clone https://github.com/git-for-windows/git \G4W
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
After importing anything with fast-import, we should always let the
garbage collector do its job, since the objects are written to disk
inefficiently.
This brings down an initial import of http://selenic.com/hg from about
230 megabytes to about 14.
In the future, we may want to make this configurable on a per-remote
basis, or maybe teach fast-import about it in the first place.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It seems to be not exactly rare on Windows to install NTFS junction
points (the equivalent of "bind mounts" on Linux/Unix) in worktrees,
e.g. to map some development tools into a subdirectory.
In such a scenario, it is pretty horrible if `git clean -dfx` traverses
into the mapped directory and starts to "clean up".
Let's just not do that. Let's make sure before we traverse into a
directory that it is not a mount point (or junction).
This addresses https://github.com/git-for-windows/git/issues/607
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, there are several categories of absolute paths. One such
category starts with a backslash and is implicitly relative to the
drive associated with the current working directory. Example:
c:
git clone https://github.com/git-for-windows/git \G4W
should clone into C:\G4W.
There is currently a problem with that, in that mingw_mktemp() does not
expect the _wmktemp() function to prefix the absolute path with the
drive prefix, and as a consequence, the resulting path does not fit into
the originally-passed string buffer. The symptom is a "Result too large"
error.
Reported by Juan Carlos Arevalo Baeza.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This happens only when the corresponding commits are not exported in
the current fast-export run. This can happen either when the relevant
commit is already marked, or when the commit is explicitly marked
as UNINTERESTING with a negative ref by another argument.
This breaks fast-export basec remote helpers.
Signed-off-by: Sverre Rabbelier <srabbelier@gmail.com>
This topic branch extends the protections introduced for Git GUI's
CVE-2022-41953 to cover `gitk`, too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Just like CVE-2022-41953 for Git GUI, there exists a vulnerability of
`gitk` where it looks for `taskkill.exe` in the current directory before
searching `PATH`.
Note that the many `exec git` calls are unaffected, due to an obscure
quirk in Tcl's `exec` function. Typically, `git.exe` lives next to
`wish.exe` (i.e. the program that is run to execute `gitk` or Git GUI)
in Git for Windows, and that is the saving grace for `git.exe because
`exec` searches the directory where `wish.exe` lives even before the
current directory, according to
https://www.tcl-lang.org/man/tcl/TclCmd/exec.htm#M24:
If a directory name was not specified as part of the application
name, the following directories are automatically searched in
order when attempting to locate the application:
The directory from which the Tcl executable was loaded.
The current directory.
The Windows 32-bit system directory.
The Windows home directory.
The directories listed in the path.
The same is not true, however, for `taskkill.exe`: it lives in the
Windows system directory (never mind the 32-bit, Tcl's documentation is
outdated on that point, it really means `C:\Windows\system32`).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
"git rev-list --unpacked --objects" failed to exclude packed
non-commit objects, which has been corrected.
* tb/rev-list-unpacked-fix:
pack-bitmap: drop --unpacked non-commit objects from results
list-objects: drop --unpacked non-commit objects from results
Leakfix.
* ps/leakfixes:
setup: fix leaking repository format
setup: refactor `upgrade_repository_format()` to have common exit
shallow: fix memory leak when registering shallow roots
test-bloom: stop setting up Git directory twice
Another step to deprecate test_i18ngrep.
* jc/test-i18ngrep:
tests: teach callers of test_i18ngrep to use test_grep
test framework: further deprecate test_i18ngrep
"git merge-file" learns a mode to read three contents to be merged
from blob objects.
* bc/merge-file-object-input:
merge-file: add an option to process object IDs
git-merge-file doc: drop "-file" from argument placeholders
"git rev-list --missing" did not work for missing commit objects,
which has been corrected.
* kn/rev-list-missing-fix:
rev-list: add commit object support in `--missing` option
rev-list: move `show_commit()` to the bottom
revision: rename bit to `do_not_die_on_missing_objects`
Teach "git show-ref" a mode to check the existence of a ref.
* ps/show-ref:
t: use git-show-ref(1) to check for ref existence
builtin/show-ref: add new mode to check for reference existence
builtin/show-ref: explicitly spell out different modes in synopsis
builtin/show-ref: ensure mutual exclusiveness of subcommands
builtin/show-ref: refactor options for patterns subcommand
builtin/show-ref: stop using global vars for `show_one()`
builtin/show-ref: stop using global variable to count matches
builtin/show-ref: refactor `--exclude-existing` options
builtin/show-ref: fix dead code when passing patterns
builtin/show-ref: fix leaking string buffer
builtin/show-ref: split up different subcommands
builtin/show-ref: convert pattern to a local variable
The codepath to traverse the commit-graph learned to notice that a
commit is missing (e.g., corrupt repository lost an object), even
though it knows something about the commit (like its parents) from
what is in commit-graph.
* ps/do-not-trust-commit-graph-blindly-for-existence:
commit: detect commits that exist in commit-graph but not in the ODB
commit-graph: introduce envvar to disable commit existence checks
Further limit tree depth max to avoid Windows build running out of
the stack space.
* jk/tree-name-and-depth-limit:
max_tree_depth: lower it for MSVC to avoid stack overflows
When performing revision queries with `--objects` and
`--use-bitmap-index`, the output may incorrectly contain objects which
are packed, even when the `--unpacked` option is given. This affects
traversals, but also other querying operations, like `--count`,
`--disk-usage`, etc.
Like in the previous commit, the fix is to exclude those objects from
the result set before they are shown to the user (or, in this case,
before the bitmap containing the result of the traversal is enumerated
and its objects listed).
This is performed by a new function in pack-bitmap.c, called
`filter_packed_objects_from_bitmap()`. Note that we do not have to
inspect individual bits in the result bitmap, since we know that the
first N (where N is the number of objects in the bitmap's pack/MIDX)
bits correspond to objects which packed by definition.
In other words, for an object to have a bitmap position (not in the
extended index), it must appear in either the bitmap's pack or one of
the packs in its MIDX.
This presents an appealing optimization to us, which is that we can
simply memset() the corresponding number of `eword_t`'s to zero,
provided that we handle any objects which spill into the next word (but
don't occupy all 64 bits of the word itself).
We only have to handle objects in the bitmap's extended index. These
objects may (or may not) appear in one or more pack(s). Since these
objects are known to not appear in either the bitmap's MIDX or pack,
they may be stored as loose, appear in other pack(s), or both.
Before returning a bitmap containing the result of the traversal back to
the caller, drop any bits from the extended index which appear in one or
more packs. This implements the correct behavior for rev-list operations
which use the bitmap index to compute their result.
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>
In git-rev-list(1), we describe the `--unpacked` option as:
Only useful with `--objects`; print the object IDs that are not in
packs.
This is true of commits, which we discard via get_commit_action(), but
not of the objects they reach. So if we ask for an --objects traversal
with --unpacked, we may get arbitrarily many objects which are indeed
packed.
I am nearly certain this behavior dates back to the introduction of
`--unpacked` via 12d2a18780 ("git rev-list --unpacked" shows only
unpacked commits, 2005-07-03), but I couldn't get that revision of Git
to compile for me. At least as early as v2.0.0 this has been subtly
broken:
$ git.compile --version
git version 2.0.0
$ git.compile rev-list --objects --all --unpacked
72791fe96c93f9ec5c311b8bc966ab349b3b5bbe
05713d991c18bbeef7e154f99660005311b5004d v1.0
153ed8b7719c6f5a68ce7ffc43133e95a6ac0fdb
8e4020bb5a8d8c873b25de15933e75cc0fc275df one
9200b628cf9dc883a85a7abc8d6e6730baee589c two
3e6b46e1b7e3b91acce99f6a823104c28aae0b58 unpacked.t
There, only the first, third, and sixth entries are loose, with the
remaining set of objects belonging to at least one pack.
The implications for this are relatively benign: bare 'git repack'
invocations which invoke pack-objects with --unpacked are impacted, and
at worst we'll store a few extra objects that should have been excluded.
Arguably changing this behavior is a backwards-incompatible change,
since it alters the set of objects emitted from rev-list queries with
`--objects` and `--unpacked`. But I argue that this change is still
sensible, since the existing implementation deviates from
clearly-written documentation.
The fix here is straightforward: avoid showing any non-commit objects
which are contained in packs by discarding them within list-objects.c,
before they are shown to the user. Note that similar treatment for
`list-objects.c::show_commit()` is not needed, since that case is
already handled by `revision.c::get_commit_action()`.
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>
Offer a slightly more verbose description of the issue fixed by
7144dee3ec (credential/libsecret: erase matching creds only, 2023-07-26)
and cb626f8e5c (credential/wincred: erase matching creds only,
2023-07-26).
Signed-off-by: Todd Zullinger <tmz@pobox.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git bugreport" learned to complain when it received a command line
argument that it will not use.
* es/bugreport-no-extra-arg:
bugreport: reject positional arguments
t0091-bugreport: stop using i18ngrep
"git send-email" did not have certain pieces of data computed yet
when it tried to validate the outging messages and its recipient
addresses, which has been sorted out.
* ms/send-email-validate-fix:
send-email: move validation code below process_address_list
"git reflog expire --single-worktree" has been broken for the past
20 months or so, which has been corrected.
* rs/reflog-expire-single-worktree-fix:
reflog: fix expire --single-worktree
