From: Johannes Schindelin <johannes.schindelin@gmx.de>
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>
---
compat/mingw.c | 65 +++++++++++++++++++++++++++++
config.mak.uname | 8 +++-
contrib/buildsystems/CMakeLists.txt | 9 +++-
meson.build | 15 ++++++-
meson_options.txt | 4 ++
t/t0060-path-utils.sh | 30 +++++++++++++
6 files changed, 127 insertions(+), 4 deletions(-)
Show changes to 6 files +127 −4
compat/mingw.c, config.mak.uname, contrib/buildsystems/CMakeLists.txt, meson.build, meson_options.txt, t/t0060-path-utils.sh
diff --git a/compat/mingw.c b/compat/mingw.c
index afdc1ef2db..563e6299bc 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -3134,6 +3134,45 @@ int xwcstoutf(char *utf, const wchar_t *wcs, size_t utflen)
return -1;
}
+#ifdef ENSURE_MSYSTEM_IS_SET
+#if !defined(RUNTIME_PREFIX) || !defined(HAVE_WPGMPTR) || !defined(MINGW_PREFIX)
+static size_t append_system_bin_dirs(char *path UNUSED, size_t size UNUSED)
+{
+ return 0;
+}
+#else
+static size_t append_system_bin_dirs(char *path, size_t size)
+{
+ char prefix[32768];
+ const char *slash;
+ size_t len = xwcstoutf(prefix, _wpgmptr, sizeof(prefix)), off = 0;
+
+ if (len == 0 || len >= sizeof(prefix) ||
+ !(slash = find_last_dir_sep(prefix)))
+ return 0;
+ /* strip trailing `git.exe` */
+ len = slash - prefix;
+
+ /* strip trailing `cmd` or `<mingw-prefix>\bin` or `bin` or `libexec\git-core` */
+ if (strip_suffix_mem(prefix, &len, "\\" MINGW_PREFIX "\\libexec\\git-core") ||
+ strip_suffix_mem(prefix, &len, "\\" MINGW_PREFIX "\\bin"))
+ off += xsnprintf(path + off, size - off,
+ "%.*s\\" MINGW_PREFIX "\\bin;", (int)len, prefix);
+ else if (strip_suffix_mem(prefix, &len, "\\cmd") ||
+ strip_suffix_mem(prefix, &len, "\\bin") ||
+ strip_suffix_mem(prefix, &len, "\\libexec\\git-core"))
+ off += xsnprintf(path + off, size - off,
+ "%.*s\\" MINGW_PREFIX "\\bin;", (int)len, prefix);
+ else
+ return 0;
+
+ off += xsnprintf(path + off, size - off,
+ "%.*s\\usr\\bin;", (int)len, prefix);
+ return off;
+}
+#endif
+#endif
+
static void setup_windows_environment(void)
{
char *tmp = getenv("TMPDIR");
@@ -3186,6 +3225,32 @@ static void setup_windows_environment(void)
setenv("HOME", tmp, 1);
}
+ if (!getenv("PLINK_PROTOCOL"))
+ setenv("PLINK_PROTOCOL", "ssh", 0);
+
+#ifdef ENSURE_MSYSTEM_IS_SET
+ if (!(tmp = getenv("MSYSTEM")) || !tmp[0]) {
+ const char *home = getenv("HOME"), *path = getenv("PATH");
+ char buf[32768];
+ size_t off = 0;
+
+ setenv("MSYSTEM", ENSURE_MSYSTEM_IS_SET, 1);
+
+ if (home)
+ off += xsnprintf(buf + off, sizeof(buf) - off,
+ "%s\\bin;", home);
+ off += append_system_bin_dirs(buf + off, sizeof(buf) - off);
+ if (path)
+ off += xsnprintf(buf + off, sizeof(buf) - off,
+ "%s", path);
+ else if (off > 0)
+ buf[off - 1] = '\0';
+ else
+ buf[0] = '\0';
+ setenv("PATH", buf, 1);
+ }
+#endif
+
if (!getenv("LC_ALL") && !getenv("LC_CTYPE") && !getenv("LANG"))
setenv("LC_CTYPE", "C.UTF-8", 1);
}
diff --git a/config.mak.uname b/config.mak.uname
index 2f7d445eb3..0b63be10b7 100644
--- a/config.mak.uname
+++ b/config.mak.uname
@@ -535,7 +535,9 @@ endif
compat/win32/pthread.o compat/win32/syslog.o \
compat/win32/trace2_win32_process_info.o \
compat/win32/dirent.o
- COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
+ COMPAT_CFLAGS = -D__USE_MINGW_ACCESS -DDETECT_MSYS_TTY \
+ -DENSURE_MSYSTEM_IS_SET="\"$(MSYSTEM)\"" -DMINGW_PREFIX="\"$(patsubst /%,%,$(MINGW_PREFIX))\"" \
+ -DNOGDI -DHAVE_STRING_H -Icompat -Icompat/regex -Icompat/win32 -DSTRIP_EXTENSION=\".exe\"
BASIC_LDFLAGS = -IGNORE:4217 -IGNORE:4049 -NOLOGO -ENTRY:wmainCRTStartup -SUBSYSTEM:CONSOLE
# invalidcontinue.obj allows Git's source code to close the same file
# handle twice, or to access the osfhandle of an already-closed stdout
@@ -758,7 +760,9 @@ ifeq ($(uname_S),MINGW)
prefix = $(MINGW_PREFIX)
HOST_CPU = $(patsubst %-w64-mingw32,%,$(MINGW_CHOST))
BASIC_LDFLAGS += -Wl,--pic-executable
- COMPAT_CFLAGS += -DDETECT_MSYS_TTY
+ COMPAT_CFLAGS += -DDETECT_MSYS_TTY \
+ -DENSURE_MSYSTEM_IS_SET="\"$(MSYSTEM)\"" \
+ -DMINGW_PREFIX="\"$(patsubst /%,%,$(MINGW_PREFIX))\""
ifeq (MINGW32,$(MSYSTEM))
BASIC_LDFLAGS += -Wl,--large-address-aware
endif
diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
index a57c4b464f..7285bd9ac2 100644
--- a/contrib/buildsystems/CMakeLists.txt
+++ b/contrib/buildsystems/CMakeLists.txt
@@ -256,7 +256,14 @@ if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
_CONSOLE DETECT_MSYS_TTY STRIP_EXTENSION=".exe" NO_SYMLINK_HEAD UNRELIABLE_FSTAT
NOGDI OBJECT_CREATION_MODE=1 __USE_MINGW_ANSI_STDIO=0
OVERRIDE_STRDUP MMAP_PREVENTS_DELETE USE_WIN32_MMAP
- HAVE_WPGMPTR ENSURE_MSYSTEM_IS_SET HAVE_RTLGENRANDOM)
+ HAVE_WPGMPTR HAVE_RTLGENRANDOM)
+ if(CMAKE_GENERATOR_PLATFORM STREQUAL "x64")
+ add_compile_definitions(ENSURE_MSYSTEM_IS_SET="MINGW64" MINGW_PREFIX="mingw64")
+ elseif(CMAKE_GENERATOR_PLATFORM STREQUAL "arm64")
+ add_compile_definitions(ENSURE_MSYSTEM_IS_SET="CLANGARM64" MINGW_PREFIX="clangarm64")
+ elseif(CMAKE_GENERATOR_PLATFORM STREQUAL "x86")
+ add_compile_definitions(ENSURE_MSYSTEM_IS_SET="MINGW32" MINGW_PREFIX="mingw32")
+ endif()
list(APPEND compat_SOURCES
compat/mingw.c
compat/winansi.c
diff --git a/meson.build b/meson.build
index 7073d5844d..a8aba81e29 100644
--- a/meson.build
+++ b/meson.build
@@ -1318,7 +1318,6 @@ elif host_machine.system() == 'windows'
libgit_c_args += [
'-DDETECT_MSYS_TTY',
- '-DENSURE_MSYSTEM_IS_SET',
'-DNATIVE_CRLF',
'-DNOGDI',
'-DNO_POSIX_GOODIES',
@@ -1328,6 +1327,20 @@ elif host_machine.system() == 'windows'
'-D__USE_MINGW_ANSI_STDIO=0',
]
+ msystem = get_option('msystem')
+ if msystem != ''
+ mingw_prefix = get_option('mingw_prefix')
+ if mingw_prefix == ''
+ mingw_prefix = msystem.to_lower()
+ elif mingw_prefix.startswith('/')
+ mingw_prefix = mingw_prefix.substring(1)
+ endif
+ libgit_c_args += [
+ '-DENSURE_MSYSTEM_IS_SET="' + msystem + '"',
+ '-DMINGW_PREFIX="' + mingw_prefix + '"'
+ ]
+ endif
+
libgit_dependencies += compiler.find_library('ntdll')
libgit_include_directories += 'compat/win32'
if compiler.get_id() == 'msvc'
diff --git a/meson_options.txt b/meson_options.txt
index dc88f130d7..becf4689bf 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -21,6 +21,10 @@ option('runtime_prefix', type: 'boolean', value: false,
description: 'Resolve ancillary tooling and support files relative to the location of the runtime binary instead of hard-coding them into the binary.')
option('sane_tool_path', type: 'array', value: [],
description: 'An array of paths to pick up tools from in case the normal tools are broken or lacking.')
+option('msystem', type: 'string', value: '',
+ description: 'Fall-back on Windows when MSYSTEM is not set.')
+option('mingw_prefix', type: 'string', value: '',
+ description: 'Fall-back on Windows when MINGW_PREFIX is not set.')
# Build information compiled into Git and other parts like documentation.
option('build_date', type: 'string', value: '',
diff --git a/t/t0060-path-utils.sh b/t/t0060-path-utils.sh
index 8545cdfab5..02906055d3 100755
--- a/t/t0060-path-utils.sh
+++ b/t/t0060-path-utils.sh
@@ -611,4 +611,34 @@ test_expect_success !VALGRIND,RUNTIME_PREFIX,CAN_EXEC_IN_PWD '%(prefix)/ works'
test_cmp expect actual
'
+test_expect_success MINGW,RUNTIME_PREFIX 'MSYSTEM/PATH is adjusted if necessary' '
+ if test -z "$MINGW_PREFIX"
+ then
+ MINGW_PREFIX="/$(echo "${MSYSTEM:-MINGW64}" | tr A-Z a-z)"
+ fi &&
+ mkdir -p "$HOME"/bin pretend"$MINGW_PREFIX"/bin \
+ pretend"$MINGW_PREFIX"/libexec/git-core pretend/usr/bin &&
+ cp "$GIT_EXEC_PATH"/git.exe pretend"$MINGW_PREFIX"/bin/ &&
+ cp "$GIT_EXEC_PATH"/git.exe pretend"$MINGW_PREFIX"/libexec/git-core/ &&
+ # copy the .dll files, if any (happens when building via CMake)
+ if test -n "$(ls "$GIT_EXEC_PATH"/*.dll 2>/dev/null)"
+ then
+ cp "$GIT_EXEC_PATH"/*.dll pretend"$MINGW_PREFIX"/bin/ &&
+ cp "$GIT_EXEC_PATH"/*.dll pretend"$MINGW_PREFIX"/libexec/git-core/
+ fi &&
+ echo "env | grep MSYSTEM=" | write_script "$HOME"/bin/git-test-home &&
+ echo "echo ${MINGW_PREFIX#/}" | write_script pretend"$MINGW_PREFIX"/bin/git-test-bin &&
+ echo "echo usr" | write_script pretend/usr/bin/git-test-bin2 &&
+
+ (
+ MSYSTEM= &&
+ GIT_EXEC_PATH= &&
+ pretend"$MINGW_PREFIX"/libexec/git-core/git.exe test-home >actual &&
+ pretend"$MINGW_PREFIX"/libexec/git-core/git.exe test-bin >>actual &&
+ pretend"$MINGW_PREFIX"/bin/git.exe test-bin2 >>actual
+ ) &&
+ test_write_lines MSYSTEM=$MSYSTEM "${MINGW_PREFIX#/}" usr >expect &&
+ test_cmp expect actual
+'
+
test_done