Commit Graph

873 Commits

Author SHA1 Message Date
Johannes Schindelin
822bebd773 Merge pull request #3220 from dscho/there-is-no-vs/master-anymore
Let the documentation reflect that there is no vs/master anymore
2021-08-11 18:56:31 -04:00
Johannes Schindelin
a58ee4a400 Merge pull request #3165 from dscho/increase-allowed-length-of-interpreter-path
mingw: allow for longer paths in `parse_interpreter()`
2021-08-11 18:56:30 -04:00
Johannes Schindelin
1190575340 Merge pull request #2915 from dennisameling/windows-arm64-support
Windows arm64 support
2021-08-11 18:56:30 -04:00
Johannes Schindelin
302dda9727 Merge pull request #2351 from PhilipOakley/vcpkg-tip
Vcpkg Install: detect lack of working Git, and note possible vcpkg time outs
2021-08-11 18:56:30 -04:00
Johannes Schindelin
3dea9c36d0 Merge pull request #2974 from derrickstolee/maintenance-and-headless
Include Windows-specific maintenance and headless-git
2021-08-11 18:56:30 -04:00
Johannes Schindelin
6fc97ba376 Merge pull request #2506 from dscho/issue-2283
Allow running Git directly from `C:\Program Files\Git\mingw64\bin\git.exe`
2021-08-11 18:56:29 -04:00
Johannes Schindelin
5ad1378552 Merge pull request #2504 from dscho/access-repo-via-junction
Handle `git add <file>` where <file> traverses an NTFS junction
2021-08-11 18:56:29 -04:00
Johannes Schindelin
aea6b00067 Merge pull request #2501 from jeffhostetler/clink-debug-curl
clink.pl: fix MSVC compile script to handle libcurl-d.lib
2021-08-11 18:56:29 -04:00
Johannes Schindelin
69b23ab834 Merge pull request #2488 from bmueller84/master
mingw: fix fatal error working on mapped network drives on Windows
2021-08-11 18:56:29 -04:00
Johannes Schindelin
516856adf8 Merge pull request #2449 from dscho/mingw-getcwd-and-symlinks
Do resolve symlinks in `getcwd()`
2021-08-11 18:56:28 -04:00
Johannes Schindelin
00953bad0f Merge pull request #2405 from dscho/mingw-setsockopt
Make sure `errno` is set when socket operations fail
2021-08-11 18:56:28 -04:00
Johannes Schindelin
5375666533 Merge branch 'dont-clean-junctions'
This topic branch teaches `git clean` to respect NTFS junctions and Unix
bind mounts: it will now stop at those boundaries.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:28 -04:00
Johannes Schindelin
5a8c40c4d1 Merge branch 'fsync-object-files-always'
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:28 -04:00
Johannes Schindelin
6c61017da7 compat/vcbuild: document preferred way to build in Visual Studio
We used to have that `make vcxproj` hack, but a hack it is. In the
meantime, we have a much cleaner solution: using CMake, either
explicitly, or even more conveniently via Visual Studio's built-in CMake
support (simply open Git's top-level directory via File>Open>Folder...).

Let's let the `README` reflect this.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:25 -04:00
Johannes Schindelin
179555c808 mingw: allow for longer paths in parse_interpreter()
As reported in https://github.com/newren/git-filter-repo/pull/225, it
looks like 99 bytes is not really sufficient to represent e.g. the full
path to Python when installed via Windows Store (and this path is used
in the hasb bang line when installing scripts via `pip`).

Let's increase it to what is probably the maximum sensible path size:
MAX_PATH. This makes `parse_interpreter()` in line with what
`lookup_prog()` handles.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Vilius Šumskas <vilius@sumskas.eu>
2021-08-11 18:56:25 -04:00
Dennis Ameling
802bfcae21 Add schannel to curl installation
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
2021-08-11 18:56:25 -04:00
Philip Oakley
c001eb38e0 vcpkg_install: add comment regarding slow network connections
The vcpkg downloads may not succeed. Warn careful readers of the time out.

A simple retry will usually resolve the issue.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:25 -04:00
Philip Oakley
50512fc8ba vcpkg_install: detect lack of Git
The vcpkg_install batch file depends on the availability of a
working Git on the CMD path. This may not be present if the user
has selected the 'bash only' option during Git-for-Windows install.

Detect and tell the user about their lack of a working Git in the CMD
window.

Fixes #2348.
A separate PR https://github.com/git-for-windows/build-extra/pull/258
now highlights the recommended path setting during install.

Signed-off-by: Philip Oakley <philipoakley@iee.email>
2021-08-11 18:56:25 -04:00
Johannes Schindelin
69bf72c5f9 win32: add a helper to run git.exe without a foreground window
On Windows, there are two kinds of executables, console ones and
non-console ones. Git's executables are all console ones.

When launching the former e.g. in a scheduled task, a CMD window pops
up. This is not what we want for the tasks installed via the `git
maintenance` command.

To work around this, let's introduce `headless-git.exe`, which is a
non-console program that does _not_ pop up any window. All it does is to
re-launch `git.exe`, suppressing that console window, passing through
all command-line arguments as-are.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
2021-08-11 18:56:25 -04:00
Ian Bearman
ea85804661 vcbuild: add an option to install individual 'features'
In this context, a "feature" is a dependency combined with its own
dependencies.

Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:25 -04:00
Ian Bearman
ffa020cac6 vcbuild: install ARM64 dependencies when building ARM64 binaries
Co-authored-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Ian Bearman <ianb@microsoft.com>
Signed-off-by: Dennis Ameling <dennis@dennisameling.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:25 -04:00
Johannes Schindelin
0e7927b4f3 mingw: implement a platform-specific strbuf_realpath()
There is a Win32 API function to resolve symbolic links, and we can use
that instead of resolving them manually. Even better, this function also
resolves NTFS junction points (which are somewhat similar to bind
mounts).

This fixes https://github.com/git-for-windows/git/issues/2481.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Jeff Hostetler
c16ee02e03 clink.pl: fix MSVC compile script to handle libcurl-d.lib
Update clink.pl to link with either libcurl.lib or libcurl-d.lib
depending on whether DEBUG=1 is set.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Bjoern Mueller
7325995571 mingw: fix fatal error working on mapped network drives on Windows
In 1e64d18 (mingw: do resolve symlinks in `getcwd()`) a problem was
introduced that causes git for Windows to stop working with certain
mapped network drives (in particular, drives that are mapped to
locations with long path names). Error message was "fatal: Unable to
read current working directory: No such file or directory". Present
change fixes this issue as discussed in
https://github.com/git-for-windows/git/issues/2480

Signed-off-by: Bjoern Mueller <bjoernm@gmx.de>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
42f7bd0b7e mingw: do resolve symlinks in getcwd()
As pointed out in https://github.com/git-for-windows/git/issues/1676,
the `git rev-parse --is-inside-work-tree` command currently fails when
the current directory's path contains symbolic links.

The underlying reason for this bug is that `getcwd()` is supposed to
resolve symbolic links, but our `mingw_getcwd()` implementation did not.

We do have all the building blocks for that, though: the
`GetFinalPathByHandleW()` function will resolve symbolic links. However,
we only called that function if `GetLongPathNameW()` failed, for
historical reasons: the latter function was supported for a long time,
but the former API function was introduced only with Windows Vista, and
we used to support also Windows XP. With that support having been
dropped, we are free to call the symbolic link-resolving function right
away.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
00025282da mingw: make sure errno is set correctly when socket operations fail
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>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
e6dd54e2cb mingw: ignore HOMEDRIVE/HOMEPATH if it points to Windows' system directory
Internally, Git expects the environment variable `HOME` to be set, and
to point to the current user's home directory.

This environment variable is not set by default on Windows, and
therefore Git tries its best to construct one if it finds `HOME` unset.

There are actually two different approaches Git tries: first, it looks
at `HOMEDRIVE`/`HOMEPATH` because this is widely used in corporate
environments with roaming profiles, and a user generally wants their
global Git settings to be in a roaming profile.

Only when `HOMEDRIVE`/`HOMEPATH` is either unset or does not point to a
valid location, Git will fall back to using `USERPROFILE` instead.

However, starting with Windows Vista, for secondary logons and services,
the environment variables `HOMEDRIVE`/`HOMEPATH` point to Windows'
system directory (usually `C:\Windows\system32`).

That is undesirable, and that location is usually write-protected anyway.

So let's verify that the `HOMEDRIVE`/`HOMEPATH` combo does not point to
Windows' system directory before using it, falling back to `USERPROFILE`
if it does.

This fixes git-for-windows#2709

Initial-Path-by: Ivan Pozdeev <vano@mail.mipt.ru>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
5c779e95d0 mingw: allow git.exe to be used instead of the "Git wrapper"
Git for Windows wants to add `git.exe` to the users' `PATH`, without
cluttering the latter with unnecessary executables such as `wish.exe`.
To that end, it invented the concept of its "Git wrapper", i.e. a tiny
executable located in `C:\Program Files\Git\cmd\git.exe` (originally a
CMD script) whose sole purpose is to set up a couple of environment
variables and then spawn the _actual_ `git.exe` (which nowadays lives in
`C:\Program Files\Git\mingw64\bin\git.exe` for 64-bit, and the obvious
equivalent for 32-bit installations).

Currently, the following environment variables are set unless already
initialized:

- `MSYSTEM`, to make sure that the MSYS2 Bash and the MSYS2 Perl
  interpreter behave as expected, and

- `PLINK_PROTOCOL`, to force PuTTY's `plink.exe` to use the SSH
  protocol instead of Telnet,

- `PATH`, to make sure that the `bin` folder in the user's home
  directory, as well as the `/mingw64/bin` and the `/usr/bin`
  directories are included. The trick here is that the `/mingw64/bin/`
  and `/usr/bin/` directories are relative to the top-level installation
  directory of Git for Windows (which the included Bash interprets as
  `/`, i.e. as the MSYS pseudo root directory).

Using the absence of `MSYSTEM` as a tell-tale, we can detect in
`git.exe` whether these environment variables have been initialized
properly. Therefore we can call `C:\Program Files\Git\mingw64\bin\git`
in-place after this change, without having to call Git through the Git
wrapper.

Obviously, above-mentioned directories must be _prepended_ to the `PATH`
variable, otherwise we risk picking up executables from unrelated Git
installations. We do that by constructing the new `PATH` value from
scratch, appending `$HOME/bin` (if `HOME` is set), then the MSYS2 system
directories, and then appending the original `PATH`.

Side note: this modification of the `PATH` variable is independent of
the modification necessary to reach the executables and scripts in
`/mingw64/libexec/git-core/`, i.e. the `GIT_EXEC_PATH`. That
modification is still performed by Git, elsewhere, long after making the
changes described above.

While we _still_ cannot simply hard-link `mingw64\bin\git.exe` to `cmd`
(because the former depends on a couple of `.dll` files that are only in
`mingw64\bin`, i.e. calling `...\cmd\git.exe` would fail to load due to
missing dependencies), at least we can now avoid that extra process of
running the Git wrapper (which then has to wait for the spawned
`git.exe` to finish) by calling `...\mingw64\bin\git.exe` directly, via
its absolute path.

Testing this is in Git's test suite tricky: we set up a "new" MSYS
pseudo-root and copy the `git.exe` file into the appropriate location,
then verify that `MSYSTEM` is set properly, and also that the `PATH` is
modified so that scripts can be found in `$HOME/bin`, `/mingw64/bin/`
and `/usr/bin/`.

This addresses https://github.com/git-for-windows/git/issues/2283

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
4ebae43188 mingw: ensure valid CTYPE
A change between versions 2.4.1 and 2.6.0 of the MSYS2 runtime modified
how Cygwin's runtime (and hence Git for Windows' MSYS2 runtime
derivative) handles locales: d16a56306d (Consolidate wctomb/mbtowc calls
for POSIX-1.2008, 2016-07-20).

An unintended side-effect is that "cold-calling" into the POSIX
emulation will start with a locale based on the current code page,
something that Git for Windows is very ill-prepared for, as it expects
to be able to pass a command-line containing non-ASCII characters to the
shell without having those characters munged.

One symptom of this behavior: when `git clone` or `git fetch` shell out
to call `git-upload-pack` with a path that contains non-ASCII
characters, the shell tried to interpret the entire command-line
(including command-line parameters) as executable path, which obviously
must fail.

This fixes https://github.com/git-for-windows/git/issues/1036

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:24 -04:00
Jeff Hostetler
c1fc640821 clink.pl: move default linker options for MSVC=1 builds
Move the default `-ENTRY` and `-SUBSYSTEM` arguments for
MSVC=1 builds from `config.mak.uname` into `clink.pl`.
These args are constant for console-mode executables.

Add support to `clink.pl` for generating a Win32 GUI application
using the `-mwindows` argument (to match how GCC does it).  This
changes the `-ENTRY` and `-SUBSYSTEM` arguments accordingly.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
2021-08-11 18:56:24 -04:00
Jeff Hostetler
53690669ad clink.pl: ignore no-stack-protector arg on MSVC=1 builds
Ignore the `-fno-stack-protector` compiler argument when building
with MSVC.  This will be used in a later commit that needs to build
a Win32 GUI app.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
2021-08-11 18:56:24 -04:00
Jeff Hostetler
1f2f630cf6 vcbuild: add support for compiling Windows resource files
Create a wrapper for the Windows Resource Compiler (RC.EXE)
for use by the MSVC=1 builds. This is similar to the CL.EXE
and LIB.EXE wrappers used for the MSVC=1 builds.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
2021-08-11 18:56:24 -04:00
Jeff Hostetler
266f3aa22c clink.pl: fix libexpatd.lib link error when using MSVC
When building with `make MSVC=1 DEBUG=1`, link to `libexpatd.lib`
rather than `libexpat.lib`.

It appears that the `vcpkg` package for "libexpat" has changed and now
creates `libexpatd.lib` for debug mode builds.  Previously, both debug
and release builds created a ".lib" with the same basename.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
2021-08-11 18:56:24 -04:00
Johannes Schindelin
1b93e9bc5e clean: remove mount points when possible
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>
2021-08-11 18:56:23 -04:00
Johannes Schindelin
e4be86c5a3 mingw: change core.fsyncObjectFiles = 1 by default
From the documentation of said setting:

	This boolean will enable fsync() when writing object files.

	This is a total waste of time and effort on a filesystem that
	orders data writes properly, but can be useful for filesystems
	that do not use journalling (traditional UNIX filesystems) or
	that only journal metadata and not file contents (OS X’s HFS+,
	or Linux ext3 with "data=writeback").

The most common file system on Windows (NTFS) does not guarantee that
order, therefore a sudden loss of power (or any other event causing an
unclean shutdown) would cause corrupt files (i.e. files filled with
NULs). Therefore we need to change the default.

Note that the documentation makes it sound as if this causes really bad
performance. In reality, writing loose objects is something that is done
only rarely, and only a handful of files at a time.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2021-08-11 18:56:23 -04:00
Johannes Schindelin
59bb1cf4dc mingw: allow absolute paths without drive prefix
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>
2021-08-11 18:56:23 -04:00
Johannes Schindelin
e78c33356f clean: do not traverse mount points
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>
2021-08-11 18:56:23 -04:00
Thomas Bétous
3e7d4888e5 mingw: align symlinks-related rmdir() behavior with Linux
When performing a rebase, rmdir() is called on the folder .git/logs. On
Unix rmdir() exits without deleting anything in case .git/logs is a
symbolic link but the equivalent functions on Windows (_rmdir, _wrmdir
and RemoveDirectoryW) do not behave the same and remove the folder if it
is symlinked even if it is not empty.

This creates issues when folders in .git/ are symlinks which is
especially the case when git-repo[1] is used: It replaces `.git/logs/`
with a symlink.

One such issue is that the _target_ of that symlink is removed e.g.
during a `git rebase`, where `delete_reflog("REBASE_HEAD")` will not
only try to remove `.git/logs/REBASE_HEAD` but then recursively try to
remove the parent directories until an error occurs, a technique that
obviously relies on `rmdir()` refusing to remove a symlink.

This was reported in https://github.com/git-for-windows/git/issues/2967.

This commit updates mingw_rmdir() so that its behavior is the same as
Linux rmdir() in case of symbolic links.

To verify that Git does not regress on the reported issue, this patch
adds a regression test for the `git rebase` symptom, even if the same
`rmdir()` behavior is quite likely to cause potential problems in other
Git commands as well.

[1]: git-repo is a python tool built on top of Git which helps manage
many Git repositories. It stores all the .git/ folders in a central
place by taking advantage of symbolic links.
More information: https://gerrit.googlesource.com/git-repo/

Signed-off-by: Thomas Bétous <tomspycell@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-08-02 15:10:58 -07:00
Junio C Hamano
6aae0e2ad2 Merge branch 'jh/simple-ipc-sans-pthread'
The "simple-ipc" did not compile without pthreads support, but the
build procedure was not properly account for it.

* jh/simple-ipc-sans-pthread:
  simple-ipc: correct ifdefs when NO_PTHREADS is defined
2021-05-22 18:29:01 +09:00
Jeff Hostetler
6aac70a870 simple-ipc: correct ifdefs when NO_PTHREADS is defined
Simple IPC always requires threads (in addition to various
platform-specific IPC support).  Fix the ifdefs in the Makefile
to define SUPPORTS_SIMPLE_IPC when appropriate.

Previously, the Unix version of the code would only verify that
Unix domain sockets were available.

This problem was reported here:
https://lore.kernel.org/git/YKN5lXs4AoK%2FJFTO@coredump.intra.peff.net/T/#m08be8f1942ea8a2c36cfee0e51cdf06489fdeafc

Reported-by: Randall S. Becker <rsbecker@nexbridge.com>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-21 07:55:00 +09:00
Junio C Hamano
4090b6973b Merge branch 'js/access-nul-emulation-on-windows'
Portability fix.

* js/access-nul-emulation-on-windows:
  msvc: avoid calling `access("NUL", flags)`
2021-04-20 17:23:37 -07:00
Johannes Schindelin
9160068ac6 msvc: avoid calling access("NUL", flags)
Apparently this is not supported with Microsoft's Universal C Runtime.
So let's not actually do that.

Instead, just return success because we _know_ that we expect the `NUL`
device to be present.

Side note: it is possible to turn off the "Null device driver" and
thereby disable `NUL`. Too many things are broken if this driver is
disabled, therefore it is not worth bothering to try to detect its
presence when `access()` is called.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-16 12:05:32 -07:00
Junio C Hamano
4c6ac2da2c Merge branch 'tb/precompose-prefix-simplify'
Streamline the codepath to fix the UTF-8 encoding issues in the
argv[] and the prefix on macOS.

* tb/precompose-prefix-simplify:
  macOS: precompose startup_info->prefix
  precompose_utf8: make precompose_string_if_needed() public
2021-04-13 15:28:51 -07:00
Torsten Bögershausen
5020774aef precompose_utf8: make precompose_string_if_needed() public
commit 5c327502 (MacOS: precompose_argv_prefix(), 2021-02-03) uses
the function precompose_string_if_needed() internally.  It is only
used from precompose_argv_prefix() and therefore static in
compat/precompose_utf8.c

Expose this function, it will be used in the next commit.

While there, allow passing a NULL pointer, which will return NULL.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-05 17:30:04 -07:00
Junio C Hamano
861794b60d Merge branch 'jh/simple-ipc'
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()
2021-04-02 14:43:14 -07:00
Jeff Hostetler
7cd5dbcaba simple-ipc: add Unix domain socket implementation
Create Unix domain socket based implementation of "simple-ipc".

A set of `ipc_client` routines implement a client library to connect
to an `ipc_server` over a Unix domain socket, send a simple request,
and receive a single response.  Clients use blocking IO on the socket.

A set of `ipc_server` routines implement a thread pool to listen for
and concurrently service client connections.

The server creates a new Unix domain socket at a known location.  If a
socket already exists with that name, the server tries to determine if
another server is already listening on the socket or if the socket is
dead.  If socket is busy, the server exits with an error rather than
stealing the socket.  If the socket is dead, the server creates a new
one and starts up.

If while running, the server detects that its socket has been stolen
by another server, it automatically exits.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-22 11:52:54 -07:00
Jeff Hostetler
59c7b88198 simple-ipc: add win32 implementation
Create Windows implementation of "simple-ipc" using named pipes.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-15 14:32:50 -07:00
Junio C Hamano
56a57652ef Sync with Git 2.30.2 for CVE-2021-21300
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-08 16:09:07 -08:00
Junio C Hamano
921846fa22 Merge branch 'jk/open-returns-eintr'
Work around platforms whose open() is reported to return EINTR (it
shouldn't, as we do our signals with SA_RESTART).

* jk/open-returns-eintr:
  config.mak.uname: enable OPEN_RETURNS_EINTR for macOS Big Sur
  Makefile: add OPEN_RETURNS_EINTR knob
2021-03-04 15:34:45 -08:00
Jeff King
2b08101204 Makefile: add OPEN_RETURNS_EINTR knob
On some platforms, open() reportedly returns EINTR when opening regular
files and we receive a signal (usually SIGALRM from our progress meter).
This shouldn't happen, as open() should be a restartable syscall, and we
specify SA_RESTART when setting up the alarm handler. So it may actually
be a kernel or libc bug for this to happen. But it has been reported on
at least one version of Linux (on a network filesystem):

  https://lore.kernel.org/git/c8061cce-71e4-17bd-a56a-a5fed93804da@neanderfunk.de/

as well as on macOS starting with Big Sur even on a regular filesystem.

We can work around it by retrying open() calls that get EINTR, just as
we do for read(), etc. Since we don't ever _want_ to interrupt an open()
call, we can get away with just redefining open, rather than insisting
all callsites use xopen().

We actually do have an xopen() wrapper already (and it even does this
retry, though there's no indication of it being an observed problem back
then; it seems simply to have been lifted from xread(), etc). But it is
used hardly anywhere, and isn't suitable for general use because it will
die() on error. In theory we could combine the two, but it's awkward to
do so because of the variable-args interface of open().

This patch adds a Makefile knob for enabling the workaround. It's not
enabled by default for any platforms in config.mak.uname yet, as we
don't have enough data to decide how common this is (I have not been
able to reproduce on either Linux or Big Sur myself). It may be worth
enabling preemptively anyway, since the cost is pretty low (if we don't
see an EINTR, it's just an extra conditional).

However, note that we must not enable this on Windows. It doesn't do
anything there, and the macro overrides the existing mingw_open()
redirection. I've added a preemptive #undef here in the mingw header
(which is processed first) to just quietly disable it (we could also
make it an #error, but there is little point in being so aggressive).

Reported-by: Aleksey Kliger <alklig@microsoft.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-26 14:15:51 -08:00