[PATCH 2/7] system_path(): Add prefix computation at runtime if RUNTIME_PREFIX set
- From
Steffen Prohaska <prohaska@zib.de>
- Date
- Sep 21, 2008, 16:24 UTC
- Message-ID
- <1222014278-11071-3-git-send-email-prohaska@zib.de>
- In-Reply-To
- <1222014278-11071-2-git-send-email-prohaska@zib.de>
This commit modifies system_path() to compute the prefix at runtime if configured to do so. If RUNTIME_PREFIX is defined, system_path() tries to strip known directories that executables can be located in from the path of the executable. If the path is successfully stripped it is used as the prefix. For example, if the executable is "/msysgit/bin/git" and BINDIR is "/bin", then the prefix is computed as "/msysgit".
We report an error if the runtime prefix computation fails, which can happen if the executable is not installed at a known location. The user should know that the global configuration is not picked up, because this can cause unexpected behavior. If we explicitly want to ignore system wide paths, we can set the environment variable GIT_CONFIG_NOSYSTEM, as our tests do.
The implementation requires that argv0_path is set up properly, which is currently the case only on Windows. argv0_path must point to the absolute path of the directory of the executable, which is verified by two calls to assert(). On Windows, the wrapper for main() (see compat/mingw.h) guarantees that this is the case. On Unix, further work is required before RUNTIME_PREFIX can be enabled.
Signed-off-by: Steffen Prohaska <prohaska@zib.de> --- Makefile | 3 +++ exec_cmd.c | 45 +++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 44 insertions(+), 4 deletions(-)
diff --git a/Makefile b/Makefile index 140a2b2..8181f74 100644 --- a/Makefile +++ b/Makefile @@ -1006,6 +1006,9 @@ ifdef INTERNAL_QSORT COMPAT_CFLAGS += -DINTERNAL_QSORT COMPAT_OBJS += compat/qsort.o endif +ifdef RUNTIME_PREFIX + COMPAT_CFLAGS += -DRUNTIME_PREFIX +endif ifdef THREADED_DELTA_SEARCH BASIC_CFLAGS += -DTHREADED_DELTA_SEARCH diff --git a/exec_cmd.c b/exec_cmd.c index ce6741e..9fa89b8 100644 --- a/exec_cmd.c +++ b/exec_cmd.c @@ -9,11 +9,48 @@ static const char *argv0_path; const char *system_path(const char *path) { - if (!is_absolute_path(path) && argv0_path) { - struct strbuf d = STRBUF_INIT; - strbuf_addf(&d, "%s/%s", argv0_path, path); - path = strbuf_detach(&d, NULL); +#ifdef RUNTIME_PREFIX + static const char *prefix; + + assert(argv0_path); + assert(is_absolute_path(argv0_path)); + + if (!prefix) { + const char *strip[] = { + GIT_EXEC_PATH, + BINDIR, + 0 + }; + const char **s; + + for (s = strip; *s; s++) { + const char *sargv = argv0_path + strlen(argv0_path); + const char *ss = *s + strlen(*s); + while (argv0_path < sargv && *s < ss + && (*sargv == *ss || + (is_dir_sep(*sargv) && is_dir_sep(*ss)))) { + sargv--; + ss--; + } + if (*s == ss) { + struct strbuf d = STRBUF_INIT; + strbuf_add(&d, argv0_path, sargv - argv0_path); + prefix = strbuf_detach(&d, NULL); + break; + } + } } + + if (!prefix) { + fprintf(stderr, "RUNTIME_PREFIX requested for path '%s', " + "but prefix computation failed.\n", path); + return path; + } + + struct strbuf d = STRBUF_INIT; + strbuf_addf(&d, "%s/%s", prefix, path); + path = strbuf_detach(&d, NULL); +#endif return path; }
-- 1.6.0.2.GIT