Outside of our Windows-specific code, the end of the environment can be
marked also by a pointer to a NUL character, not only by a NULL pointer
as our code assumed so far.
That led to a buffer overrun in `make_environment_block()` when running
`git-remote-https` in `mintty` (because `curl_global_init()` added the
`CHARSET` environment variable *outside* of `mingw_putenv()`, ending the
environment in a pointer to an empty string).
Side note for future debugging on Windows: when running programs in
`mintty`, the standard input/output/error is not connected to a Win32
Console, but instead is pipe()d. That means that even stderr may not be
written completely before a crash, but has to be fflush()ed explicitly.
For example, when debugging crashes, the developer should insert an
`fflush(stderr);` at the end of the `error()` function defined in
usage.c.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It is unlikely that we have an empty environment, ever, but *if* we do,
when `environ_size - 1` is passed to `bsearchenv()` it is misinterpreted
as a real large integer.
To make the code truly defensive, refuse to do anything at all if the
size is negative (which should not happen, of course).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The `git_terminal_prompt()` function expects the terminal window to be
attached to a Win32 Console. However, this is not the case with terminal
windows other than `cmd.exe`'s, e.g. with MSys2's own `mintty`.
Non-cmd terminals such as `mintty` still have to have a Win32 Console
to be proper console programs, but have to hide the Win32 Console to
be able to provide more flexibility (such as being resizeable not only
vertically but also horizontally). By writing to that Win32 Console,
`git_terminal_prompt()` manages only to send the prompt to nowhere and
to wait for input from a Console to which the user has no access.
This commit introduces a function specifically to support `mintty` -- or
other terminals that are compatible with MSys2's `/dev/tty` emulation. We
use the `TERM` environment variable as an indicator for that: if the value
starts with "xterm" (such as `mintty`'s "xterm_256color"), we prefer to
let `xterm_prompt()` handle the user interaction.
To handle the case when standard input/output are redirected – as is the
case when pushing via HTTPS: `git-remote-https`' standard input and
output are pipes from/to the main Git executable – we make use of the
`MSYS_TTY_HANDLES` environment variable that was introduced to
fix another bug in MSys2-based Git: this environment variable contains
the Win32 `HANDLE`s of the standard input, output and error as originally
passed from MSys2 to the Git executable, enclosed within space
characters, skipping handles that do not refer to the terminal window
(e.g. when they were redirected). We will only use those handles when
that environment variable lists all three handles because then we can be
100% certain that we are running inside a terminal window, and that we
know exactly which Win32 handles to use to communicate with it.
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: nalla <nalla@hamal.uberspace.de>
This reduces the disk footprint of a full Git for Windows setup
dramatically because on Windows, one cannot assume that hard links are
supported.
The net savings are calculated easily: the 32-bit `git.exe` file weighs
in with 7662 kB while the `git-wrapper.exe` file (modified to serve as a
drop-in replacement for builtins) weighs a scant 21 kB. At this point,
there are 109 builtins which results in a total of 813 MB disk space
being freed up by this commit.
Yes, that is really more than half a gigabyte.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Git started out as a bunch of separate commands, in the true Unix spirit.
Over time, more and more functionality was shared between the different
Git commands, though, so it made sense to introduce the notion of
"builtins": programs that are actually integrated into the main Git
executable.
These builtins can be called in two ways: either by specifying a
subcommand as the first command-line argument, or -- for backwards
compatibility -- by calling the Git executable hardlinked to a filename
of the form "git-<subcommand>". Example: the "log" command can be called
via "git log <parameters>" or via "git-log <parameters>". The latter
form is actually deprecated and only supported for scripts; calling
"git-log" interactively will not even work by default because the
libexec/git-core/ directory is not in the PATH.
All of this is well and groovy as long as hard links are supported.
Sadly, this is not the case in general on Windows. So it actually hurts
quite a bit when you have to fall back to copying all of git.exe's
currently 7.5MB 109 times, just for backwards compatibility.
The simple solution would be to install really trivial shell script
wrappers in place of the builtins:
for builtin in $BUILTINS
do
rm git-$builtin.exe
printf '#!/bin/sh\nexec git %s "$@"\n' $builtin > git-builtin
chmod a+x git-builtin
done
This method would work -- even on Windows because Git for Windows ships a
full-fledged Bash. However, the Windows Bash comes at a price: it needs to
spin up a full-fledged POSIX emulation layer everytime it starts.
Therefore, the shell script solution would incur a significant performance
penalty.
The best solution the Git for Windows team could come up with is to extend
the Git wrapper -- that is needed to call Git from cmd.exe anyway, and
that weighs in with a scant 19KB -- to also serve as a drop-in replacement
for the builtins so that the following workaround is satisfactory:
for builtin in $BUILTINS
do
cp git-wrapper.exe git-$builtin.exe
done
This commit allows for this, by extending the module file parsing to
turn builtin command names like `git-log.exe ...` into calls to the main
Git executable: `git.exe log ...`.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This prepares the wrapper for modifications to serve as a drop-in
replacement for the builtins.
This commit's diff is best viewed with the `-w` flag.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
We take care to embed the manifest, too, because we will modify the
wrapper in the next few commits to serve as a drop-in replacement for
the built-ins, i.e. we will want to call the wrapper under names such
as 'git-patch-id.exe', too.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, Git is faced by the challenge that it has to set up certain
environment variables before running Git under special circumstances
such as when Git is called directly from cmd.exe (i.e. outside any
Bash environment).
This source code was taken from msysGit's commit 74a198d:
https://github.com/msysgit/msysgit/blob/74a198d/src/git-wrapper/git-wrapper.c
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows >= Vista, not having an application manifest with a
requestedExecutionLevel can cause several kinds of confusing behavior.
The first and more obvious behavior is "Installer Detection", where
Windows sometimes decides (by looking at things like the file name and
even sequences of bytes within the executable) that an executable is an
installer and should run elevated (causing the well-known popup dialog
to appear). In Git's context, subcommands such as "git patch-id" or "git
update-index" fall prey to this behavior.
The second and more confusing behavior is "File Virtualization". It
means that when files are written without having write permission, it
does not fail (as expected), but they are instead redirected to
somewhere else. When the files are read, the original contents are
returned, though, not the ones that were just written somewhere else.
Even more confusing, not all write accesses are redirected; Trying to
write to write-protected .exe files, for example, will fail instead of
redirecting.
In addition to being unwanted behavior, File Virtualization causes
dramatic slowdowns in Git (see for instance
http://code.google.com/p/msysgit/issues/detail?id=320).
There are two ways to prevent those two behaviors: Either you embed an
application manifest within all your executables, or you add an external
manifest (a file with the same name followed by .manifest) to all your
executables. Since Git's builtins are hardlinked (or copied), it is
simpler and more robust to embed a manifest.
A recent enough MSVC compiler should already embed a working internal
manifest, but for MinGW you have to do so by hand.
Very lightly tested on Wine, where like on Windows XP it should not make
any difference.
References:
- New UAC Technologies for Windows Vista
http://msdn.microsoft.com/en-us/library/bb756960.aspx
- Create and Embed an Application Manifest (UAC)
http://msdn.microsoft.com/en-us/library/bb756929.aspx
[js: simplified the embedding dramatically by reusing Git for Windows'
existing Windows resource file, removed the optional (and dubious)
processorArchitecture attribute of the manifest's assemblyIdentity
section.]
Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When the rename function tries to move a directory it fails if the target
directory exists. It should check if it can delete the (possibly empty)
target directory and then try again to move the directory.
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: 마누엘 <nalla@users.noreply.github.com>
With MSys2, the sigset_t type is defined in sys/types.h, therefore we
need to #include said file.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This test assumed that there are no two equivalent directory separators.
However, on Windows, the back slash and the forward slash *are*
equivalent. Let's paper over this issue by converting the backward
slashes to forward ones in the test that fails with MSys2 otherwise.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When shell scripts access a $TMP variable containing backslashes, they
will be mistaken for escape characters. Let's not let that happen by
converting them to forward slashes.
This fixes t7800 with MSys2.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
There is a really useful debugging technique developed by Sverre
Rabbelier that inserts "bash &&" somewhere in the test scripts, letting
the developer interact at given points with the current state.
Another debugging technique, used a lot by this here coder, is to run
certain executables via gdb by guarding a "gdb -args" call in
bin-wrappers/git.
Both techniques were disabled by 781f76b1(test-lib: redirect stdin of
tests).
Let's reinstate the ability to run an interactive shell by making the
redirection optional: setting the TEST_NO_REDIRECT environment variable
will skip the redirection.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This test is susceptible to MSys2's posix-to-windows path mangling; Let's
just use POSIX paths throughout and let the tests pass.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With MSys2, there is actually an implementation of mkfifo available. The
only problem is that it is only emulating named pipes through the MSys2
runtime; The Win32 API has no idea about named pipes, hence the Git
executable cannot access those pipes either.
The symptom is that Git fails with a '<name>: No such file or directory'
because MSys2 emulates named pipes through special-crafted '.lnk' files.
The solution is to tell the test suite explicitly that we cannot use
named pipes when we want to test a MinGW Git.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
MSys2 actually allows to create files or directories whose names contain
tabs, newlines or colors, even if plain Win32 API cannot access them.
As we are using an MSys2 bash to run the tests, such files or
directories are created successfully, but Git has no chance to work with
them because it is a regular Windows program, hence limited by the Win32
API.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
With MSys2, the "TZ" environment variable gets filtered out when calling
non-MSys2 executables. The reason is that Windows' time zone handling is
substantially different from the POSIX one.
However, we just taught Git for Windows' fork of the MSys2 runtime to
pass on the timezone in a different environment variable, MSYS2_TZ for
the sole purpose of Git being able to reinterpret it correctly.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The unsetenv code has no idea to update our environ_size, therefore
causing segmentation faults when environment variables are removed
without compat/mingw.c's knowing (MinGW's optimized lookup would try
to strcmp() against NULL in such a case).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It does not quite work because it produces DOS line endings which the
shell does not like at all.
This lets t3406, t3903, t4254, t7400, t7401, t7406 and t7407 pass.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This just makes things compile, the test suite most likely needs extra
tender loving care in addition to this change.
While at it, also allow building MSys2 Git (i.e. a Git that uses MSys2's
POSIX emulation layer).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The excellent MSys2 project brings a substantially updated MinGW
environment including newer GCC versions and new headers. To support
compiling Git, let's special-case the new MinGW (tell-tale: the
_MINGW64_VERSION_MAJOR constant is defined).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
MSys2's strace facility is very useful for debugging... With this patch,
the bash will be executed through strace if the environment variable
GIT_STRACE_COMMANDS is set, which comes in real handy when investigating
issues in the test suite.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
This way the libraries get properly installed into the "site_perl"
directory and we just have to move them out of the "mingw" directory.
Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
On Windows, we would like to be able to have a default http.sslCAinfo
that points to an MSys path (i.e. relative to the installation root of
Git). As Git is a MinGW program, it has to handle the conversion
of the MSys path into a MinGW32 path itself.
Since system_path() considers paths starting with '/' as absolute, we
have to convince it to make a Windows path by stripping the leading
slash.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
"git log --decorate" did not reset colors correctly around the
branch names.
* jc/decorate-leaky-separator-color:
log --decorate: do not leak "commit" color into the next item
Documentation/config.txt: simplify boolean description in the syntax section
Documentation/config.txt: describe 'color' value type in the "Values" section
Documentation/config.txt: have a separate "Values" section
Documentation/config.txt: describe the structure first and then meaning
Documentation/config.txt: explain multi-valued variables once
Documentation/config.txt: avoid unnecessary negation
"git -C '' subcmd" refused to work in the current directory, unlike
"cd ''" which silently behaves as a no-op.
* kn/git-cd-to-empty:
git: treat "git -C '<path>'" as a no-op when <path> is empty
"git imap-send" learned to optionally talk with an IMAP server via
libcURL; because there is no other option when Git is built with
NO_OPENSSL option, use that codepath by default under such
configuration.
* km/imap-send-libcurl-options:
imap-send: use cURL automatically when NO_OPENSSL defined
Workarounds for certain build of GPG that triggered false breakage
in a test.
* mg/verify-commit:
t7510: do not fail when gpg warns about insecure memory
"git rebase -i" recently started to include the number of
commits in the insn sheet to be processed, but on a platform
that prepends leading whitespaces to "wc -l" output, the numbers
are shown with extra whitespaces that aren't necessary.
* es/rebase-i-count-todo:
rebase-interactive: re-word "item count" comment
rebase-interactive: suppress whitespace preceding item count
We did not parse username followed by literal IPv6 address in SSH
transport URLs, e.g. ssh://user@[2001:db8::1]:22/repo.git
correctly.
* tb/connect-ipv6-parse-fix:
t5500: show user name and host in diag-url
t5601: add more test cases for IPV6
connect.c: allow ssh://user@[2001:db8::1]/repo.git
The environment is modified in most surprising circumstances, and not
all of them are under Git's control. For example, calling
curl_global_init() on Windows will ensure that the CHARSET variable is
set, adding one if necessary.
While the previous commit worked around crashes triggered by such
outside changes of the environment by relaxing the requirement that the
environment be terminated by a NULL pointer, the other assumption made
by `mingw_getenv()` and `mingw_putenv()` is that the environment is
sorted, for efficient lookup via binary search.
Let's make real sure that our environment is intact before querying or
modifying it, and reinitialize our idea of the environment if necessary.
With this commit, before working on the environment we look briefly for
indicators that the environment was modified outside of our control, and
to ensure that it is terminated with a NULL pointer and sorted again in
that case.
Note: the indicators are maybe not sufficient. For example, when a
variable is removed, it will not be noticed. It might also be a problem
if outside changes to the environment result in a modified `environ`
pointer: it is unclear whether such a modification could result in a
problem when `mingw_putenv()` needs to `realloc()` the environment
buffer.
For the moment, however, the current fix works well enough, so let's
only face the potential problems when (and if!) they occur.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
