René ScharfeOn Windows the environment variable PATH contains a semicolon-separated list of directories to search for, in order, when looking for the location of a binary to run. get_path_split() parses it and returns an array of string copies, which is iterated by path_lookup(), which in turn passes each entry to lookup_prog().
Change lookup_prog() to take the directory name as a length-limited string instead of as a NUL-terminated one and parse PATH directly in path_lookup(). This avoids memory allocations, simplifying the code.
Signed-off-by: Rene Scharfe <l.s.r@web.de> --- compat/mingw.c | 96 ++++++++++++++-------------------------------------------- 1 file changed, 22 insertions(+), 74 deletions(-)
Show changes to compat/mingw.c +22 −74
diff --git a/compat/mingw.c b/compat/mingw.c index 5113071bc7..7bc61d4066 100644 --- a/compat/mingw.c +++ b/compat/mingw.c @@ -1154,67 +1154,15 @@ static const char *parse_interpreter(const char *cmd) } /* - * Splits the PATH into parts. - */ -static char **get_path_split(void) -{ - char *p, **path, *envpath = mingw_getenv("PATH"); - int i, n = 0; - - if (!envpath || !*envpath) - return NULL; - - envpath = xstrdup(envpath); - p = envpath; - while (p) { - char *dir = p; - p = strchr(p, ';'); - if (p) *p++ = '\0'; - if (*dir) { /* not earlier, catches series of ; */ - ++n; - } - } - if (!n) { - free(envpath); - return NULL; - } - - ALLOC_ARRAY(path, n + 1); - p = envpath; - i = 0; - do { - if (*p) - path[i++] = xstrdup(p); - p = p+strlen(p)+1; - } while (i < n); - path[i] = NULL; - - free(envpath); - - return path; -} - -static void free_path_split(char **path) -{ - char **p = path; - - if (!path) - return; - - while (*p) - free(*p++); - free(path); -} - -/* * exe_only means that we only want to detect .exe files, but not scripts * (which do not have an extension) */ -static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only) +static char *lookup_prog(const char *dir, int dirlen, const char *cmd, + int isexe, int exe_only) { char path[MAX_PATH]; wchar_t wpath[MAX_PATH]; - snprintf(path, sizeof(path), "%s\\%s.exe", dir, cmd); + snprintf(path, sizeof(path), "%.*s\\%s.exe", dirlen, dir, cmd); if (xutftowcs_path(wpath, path) < 0) return NULL; @@ -1235,17 +1183,27 @@ static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_on * Determines the absolute path of cmd using the split path in path. * If cmd contains a slash or backslash, no lookup is performed. */ -static char *path_lookup(const char *cmd, char **path, int exe_only) +static char *path_lookup(const char *cmd, int exe_only) { + const char *path; char *prog = NULL; int len = strlen(cmd); int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe"); if (strchr(cmd, '/') || strchr(cmd, '\\')) - prog = xstrdup(cmd); + return xstrdup(cmd); - while (!prog && *path) - prog = lookup_prog(*path++, cmd, isexe, exe_only); + path = mingw_getenv("PATH"); + if (!path) + return NULL; + + for (; !prog && *path; path++) { + const char *sep = strchrnul(path, ';'); + if (sep == path) + continue; + prog = lookup_prog(path, sep - path, cmd, isexe, exe_only); + path = sep; + } return prog; } @@ -1569,13 +1527,10 @@ static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **deltaen } if (getenv("GIT_STRACE_COMMANDS")) { - char **path = get_path_split(); - char *p = path_lookup("strace.exe", path, 1); + char *p = path_lookup("strace.exe", 1); if (!p) { - free_path_split(path); return error("strace not found!"); } - free_path_split(path); if (xutftowcs_path(wcmd, p) < 0) { free(p); return -1; @@ -1634,8 +1589,7 @@ pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **deltaenv, int fhin, int fhout, int fherr) { pid_t pid; - char **path = get_path_split(); - char *prog = path_lookup(cmd, path, 0); + char *prog = path_lookup(cmd, 0); if (!prog) { errno = ENOENT; @@ -1646,7 +1600,7 @@ pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **deltaenv, if (interpr) { const char *argv0 = argv[0]; - char *iprog = path_lookup(interpr, path, 1); + char *iprog = path_lookup(interpr, 1); argv[0] = prog; if (!iprog) { errno = ENOENT; @@ -1664,21 +1618,18 @@ pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **deltaenv, fhin, fhout, fherr); free(prog); } - free_path_split(path); return pid; } static int try_shell_exec(const char *cmd, char *const *argv) { const char *interpr = parse_interpreter(cmd); - char **path; char *prog; int pid = 0; if (!interpr) return 0; - path = get_path_split(); - prog = path_lookup(interpr, path, 1); + prog = path_lookup(interpr, 1); if (prog) { int argc = 0; #ifndef _MSC_VER @@ -1700,7 +1651,6 @@ static int try_shell_exec(const char *cmd, char *const *argv) free(prog); free(argv2); } - free_path_split(path); return pid; } @@ -1722,8 +1672,7 @@ int mingw_execv(const char *cmd, char *const *argv) int mingw_execvp(const char *cmd, char *const *argv) { - char **path = get_path_split(); - char *prog = path_lookup(cmd, path, 0); + char *prog = path_lookup(cmd, 0); if (prog) { mingw_execv(prog, argv); @@ -1731,7 +1680,6 @@ int mingw_execvp(const char *cmd, char *const *argv) } else errno = ENOENT; - free_path_split(path); return -1; }
-- 2.12.1.windows.1
