Commit Graph

31 Commits

Author SHA1 Message Date
Johannes Schindelin
136446ae7b mingw: let the Git wrapper determine the top-level directory
The Git wrapper is also used as a redirector for Git for Windows'
bin\bash.exe dropin: for backwards-compatibility, bin\bash.exe exists
and simply sets up the environment variables before executing the
*real* bash.

However, due to our logic to use the directory in which the `.exe`
lives as top-level directory (or one directory below for certain, known
basenames such as `git.exe` and `gitk.exe`), the `PATH` environment
variable was prefixed with the `/bin/bin` and `/bin/mingw/bin`
directories -- which makes no sense.

Instead, let's just auto-detect the top-level directory in the common
case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:47 +02:00
Johannes Schindelin
0aad30a263 mingw: clean up the Git wrapper a bit
We should not conflate the 'exepath' with the 'top-level
directory'. The former should be the directory in which the executable
lives while the latter should be the top-level directory ("POSIX root
directory") as far as Git is concerned.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:47 +02:00
Johannes Schindelin
97be855990 git-wrapper: also allow setting the application ID
Windows 7 allows users to pin running applications to the task bar. By
setting the application ID, multiple processes can share a single task
bar entry, and this is exactly what we need for `git-bash.exe` which
wants to share the task bar entry with the `mintty.exe` instance it
launches.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:46 +02:00
Johannes Schindelin
431c6635f7 git-wrapper: leave the working directory alone by default
The idea of `git-bash.exe` automatically running the Git Bash in the
home directory was to support the start menu item `Git Bash` (which
should not start in C:\Program Files\Git, but in $HOME), and to make
that behavior consistent with double-clicking in `git-bash.exe`
portable Git.

However, it turns out that one of the main use cases of portable Git is
to run the Git Bash in GitHub for Windows, and it should start in the
top-level directory of a given project. Therefore, the concern to keep
double-clicking `git-bash.exe` consistent with the start menu item was
actually unfounded.

As to the start menu item: it can easily be changed to launch
`git-bash.exe` with a command-line option. So let's introduce the
--cd-to-home option for that purpose.

As a bonus, the Git wrapper can now also serve as a drop-in redirector
/bin/bash.exe to provide backwards-compatibility of Git for Windows 2.x
with 1.x: some 3rd-party software expects to find that executable there,
and it also expects it to leave the working directory unchanged.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:45 +02:00
Johannes Schindelin
c205287d42 git-wrapper: allow overriding the command to spawn via command-line args
By embedding string resources into the Git wrapper executable, it
can be configured to execute custom commands (after setting up the
environment in the way required for Git for Windows to work properly).
This feature is used e.g. for `git-bash.exe` which launches a Bash in
the configured terminal window.

Here, we introduce command-line options to override those string
resources. That way, a user can call `git-bash.exe` (which is a copy of
the Git wrapper with `usr\bin\bash.exe --login -i` embedded as string
resource) with command-line options that will override what command is
run.

ConEmu, for example, might want to call

	...\git-bash.exe --needs-console --no-hide --minimal-search-path ^
		--command=usr\\bin\\bash.exe --login -i

In particular, the following options are supported now:

--command=<command-line>::
	Executes `<command-line>` instead of the embedded string resource

--[no-]minimal-search-path::
	Ensures that only `/cmd/` is added to the `PATH` instead of
	`/mingw??/bin` and `/usr/bin/`, or not

--[no-]needs-console::
	Ensures that there is a Win32 console associated with the spawned
	process, or not

--[no-]hide::
	Hides the console window, or not

Helped-by: Eli Young <elyscape@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:44 +02:00
Johannes Schindelin
e33d433cc4 git wrapper: auto-grow buffer in expand_variables()
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:44 +02:00
Johannes Schindelin
714799ae60 git wrapper: refactor @@VAR@@ expansion into its own function
We will enhance the function in the next commit to support @@VAR@@
expansion in the upcoming `--command=<command>` option.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:43 +02:00
Johannes Schindelin
f44e8264aa git wrapper: refactor extraction of 1st arg into its own function
This will be reused by the upcoming `--command=<command>` option.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:43 +02:00
Nico Rieck
5e404f5440 git-wrapper: let git gui run in the background
This fixes https://github.com/git-for-windows/git/issues/172.

Signed-off-by: Nico Rieck <nico.rieck@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:42 +02:00
Karsten Blees
6f42d91b3d git-wrapper: don't set the console input code page
Using different code pages for console input (SetConsoleCP()) and console
output (SetConsoleOutputCP()) doesn't make much sense and may be hazardous
for native Windows programs.

Git uses UTF-8 internally, so it actually needs 'SetConsoleCP(CP_UTF8)'
rather than 'SetConsoleCP(GetACP())'. However, ReadFile() / ReadConsoleA()
are broken with CP_UTF8 (and thus any higher level APIs such as fgetc(),
getchar() etc.). Unicode-aware console input would have to be implemented
via mingw_* wrappers using ReadConsoleW(). As Git typically launches an
editor for anything more complex than ASCII-only, yes/no-style questions,
this is currently not a problem.

Drop 'SetConsoleCP()' from the git-wrapper, so that input and output code
pages stay in sync.

Signed-off-by: Karsten Blees <blees@dcon.de>
2016-06-07 09:09:42 +02:00
Johannes Schindelin
e57e97cc45 git-wrapper: support the non-mintty fall-back for Git Bash
When we fall back to starting the Git Bash in the regular Windows
console, we need to show said console's window... So let's introduce yet
another configuration knob for use via string resources.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:41 +02:00
Johannes Schindelin
4b39e93498 git wrapper: allow _Git Bash_ to run with a newly allocated console
With a recent change in Cygwin (which is the basis of the msys2-runtime),
a GUI process desiring to launch an MSys2 executable needs to allocate a
console for the new process (otherwise the process will just hang on
Windows XP). _Git Bash_ is such a GUI process.

While at it, use correct handles when inheriting the stdin/stdout/stderr
handles: `GetStdHandle()` returns NULL for invalid handles, but the
STARTUPINFO must specify `INVALID_HANDLE_VALUE` instead.

Originally, the hope was that only this `NULL` => `INVALID_HANDLE_VALUE`
conversion would be required to fix the Windows XP issue mentioned above
(extensive debugging revealed that starting _Git Bash_ on Windows XP would
yield invalid handles for `stdin` and `stderr`, but *not* for `stdout`).

However, while _Git Bash_ eventually showed a `mintty` when not allocating
a new console, it took around one second to show it, and several seconds
to close it. So let's just include both fixes.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:41 +02:00
Johannes Schindelin
6bf3b09f2f git-wrapper: prepare to allow more options than MINIMAL_PATH
With the resource-driven command-line configuration, we introduced the
option to ensure that only the PATH environment variable is edited only
minimally, i.e. only /cmd/ is added (as appropriate for _Git CMD_).

We are about to add another option, so let's refactor the equivalent of
Git's `strip_prefix()` function; It is not *quite* the same because we
have to `memmove()` the remainder to the beginning of the buffer.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:40 +02:00
Karsten Blees
9b3bfd746c git-wrapper: remove redundant TERM initialization
Remove redundant TERM initialization from git-wrapper in favor of TERM
initialization in git itself.

Signed-off-by: Karsten Blees <blees@dcon.de>
2016-06-07 09:09:40 +02:00
Karsten Blees
73ea3b724b git-wrapper: fix HOME initialization
git-wrapper fails to initialize HOME correctly if $HOMEDRIVE$HOMEPATH
points to a disconnected network drive.

Check if the directory exists before using $HOMEDRIVE$HOMEPATH.

Signed-off-by: Karsten Blees <blees@dcon.de>
2016-06-07 09:09:39 +02:00
Vitaly Takmazov
ecc4edcd29 git-wrapper: case-insensitive path comparison 2016-06-07 09:09:39 +02:00
Johannes Schindelin
e2cb5b8342 git-wrapper: interpret --cd=<directory> when configured via resources
This change accompanies the `--no-cd` option when configured via
resources. It is required to support `Git Bash Here`: when
right-clicking an icon in the Explorer to start a Bash, the working
directory is actually the directory that is displayed in the Explorer.
That means if the clicked icon actually refers to a directory, the
working directory would be its *parent* directory.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:39 +02:00
Johannes Schindelin
131c023c53 git-wrapper: serve as git-gui.exe, too
To avoid that ugly Console window when calling \cmd\git.exe gui...

To avoid confusion with builtins, we need to move the code block
handling gitk (and now git-gui, too) to intercept before git-gui is
mistaken for a builtin.

Unfortunately, git-gui is in libexec/git-core/ while gitk is in bin/,
therefore we need slightly more adjustments than just moving and
augmenting the gitk case.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:38 +02:00
nalla
a8b5dec4bc git-wrapper: support git.exe and gitk.exe to be in a spaced dir
When *Git for Windows* is installed into a directory that has spaces in
it, e.g. `C:\Program Files\Git`, the `git-wrapper` appends this directory
unquoted when fixing up the command line. To resolve this, just quote the
provided `execpath`.

Signed-off-by: nalla <nalla@hamal.uberspace.de>
2016-06-07 09:09:38 +02:00
Johannes Schindelin
5107d040b4 git-wrapper: Allow git-cmd.exe to add only /cmd/ to the PATH
The idea of having the Git wrapper in the /cmd/ directory is to allow
adding only a *tiny* set of executables to the search path, to allow
minimal interference with other software applications. It is quite
likely, for example, that other software applications require their own
version of zlib1.dll and would not be overly happy to find the version
Git for Windows ships.

The /cmd/ directory also gives us the opportunity to let the Git wrapper
handle the `gitk` script. It is a Tcl/Tk script that is not recognized
by Windows, therefore calling `gitk` in `cmd.exe` would not work, even
if we add all of Git for Windows' bin/ directories.

So let's use the /cmd/ directory instead of adding /mingw??/bin/ and
/usr/bin/ to the PATH when launching Git CMD.

The way we implemented Git CMD is to embed the appropriate command line
as string resource into a copy of the Git wrapper. Therefore we extended
that syntax to allow for configuring a minimal search path.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:37 +02:00
Johannes Schindelin
0d11d3db2b git-wrapper: optionally skip cd $HOME when configured via resources
We recently added the ability to configure copies of the Git wrapper to
launch custom command-lines, configured via plain old Windows resources.
The main user is Git for Windows' `git-bash.exe`, of course. When the
user double-clicks the `git bash` icon, it makes sense to start the Bash
in the user's home directory.

Third-party software, such as TortoiseGit or GitHub for Windows, may
want to start the Git Bash in another directory, though.

Now, when third-party software wants to call Git, they already have to
construct a command-line, and can easily pass a command-line option
`--no-cd` (which this commit introduces), and since that option is not
available when the user double-clicks an icon on the Desktop or in the
Explorer, let's keep the default to switch to the home directory if the
`--no-cd` flag was not passed along.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:37 +02:00
Johannes Schindelin
7cd7f40ba2 git-wrapper: make command-line argument skipping more robust
When we rewrite the command-line to call the *real* Git, we want to skip
the first command-line parameter. The previous code worked in most
circumstances, but was a bit fragile because it assumed that no fancy
quoting would take place.

In the next commit, we will want to have the option to skip more than
just one command-line parameter, so we have to be much more careful with
the command-line handling.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:36 +02:00
Johannes Schindelin
1c56ef2f09 git-wrapper: remove 'gui' and 'citool' handling
In the meantime, Git for Windows learned to handle those subcommands
quite well itself; There is no longer a need to special-case them in the
wrapper.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:36 +02:00
Johannes Schindelin
342d115864 Let the Git wrapper replace cmd\gitk.cmd, too
In a push to polish Git for Windows more, we are moving away from
scripts toward proper binaries.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:35 +02:00
Johannes Schindelin
5cd810ca41 Git wrapper: allow overriding what executable is called
The Git wrapper does one thing, and does it well: setting up the
environment required to run Git and its scripts, and then hand off to
another program.

We already do this for the Git executable itself; in Git for Windows'
context, we have exactly the same need also when calling the Git Bash or
Git CMD. However, both are tied to what particular shell environment you
use, though: MSys or MSys2 (or whatever else cunning developers make
work for them). This means that the Git Bash and Git CMD need to be
compiled in the respective context (e.g. when compiling the
mingw-w64-git package in the MSys2 context).

Happily, Windows offers a way to configure compiled executables:
resources. So let's just look whether the current executable has a
string resource and use it as the command-line to execute after the
environment is set up. To support MSys2's Git Bash better (where
`mintty` should, but might not, be available), we verify whether the
specified executable exists, and keep looking for string resources if it
does not.

For even more flexibility, we expand environment variables specified as
`@@<VARIABLE-NAME>@@`, and for convenience `@@EXEPATH@@` expands into
the directory in which the executable resides.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:35 +02:00
Johannes Schindelin
8a6acc1fec git-wrapper: inherit stdin/stdout/stderr even without a console
Otherwise the output of Git commands cannot be caught by, say, Git GUI
(because it is running detached from any console, which would make
`git.exe` inherit the standard handles implicitly).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:35 +02:00
Johannes Schindelin
6c44ca587b git-wrapper: prepare for executing configurable command-lines
We are about to use the Git wrapper to call the Git Bash of Git for
Windows. All the wrapper needs to do for that is to set up the
environment variables, use the home directory as working directory and
then hand off to a user-specified command-line.

We prepare the existing code for this change by introducing flags to set
up the environment variables, to launch a non-Git program, and to use
the home directory as working directory.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:34 +02:00
Johannes Schindelin
dcd15a39ef git-wrapper: support MSys2
The original purpose of the Git wrapper is to run from inside Git for
Windows' /cmd/ directory, to allow setting up some environment variables
before Git is allowed to take over.

Due to differences in the file system layout, MSys2 requires some
changes for that to work.

In addition, we must take care to set the `MSYSTEM` environment variable
to `MINGW32` or `MINGW64`, respectively, to allow MSys2 to be configured
correctly in case Git launches a shell or Perl script.

We also need to change the `TERM` variable to `cygwin` instead of
`msys`, otherwise the pager `less.exe` (spawned e.g. by `git log`) will
simply crash with a message similar to this one:

	1 [main] less 9832 cygwin_exception::open_stackdumpfile:
	Dumping stack trace to less.exe.stackdump

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
2016-06-07 09:09:34 +02:00
Johannes Schindelin
dcfe38d2a7 Let the Git wrapper serve as a drop-in replacement for builtins
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>
2016-06-07 09:09:33 +02:00
Johannes Schindelin
eb2559896f Refactor git-wrapper into more functions
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>
2016-06-07 09:09:33 +02:00
Johannes Schindelin
e4ce26b38f Add Git for Windows' wrapper executable
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>
2016-06-07 09:09:32 +02:00