exec_cmd.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "quote.h"
   4 #include "argv-array.h"
   5 #define MAX_ARGS        32
   6
   7 static const char *argv_exec_path;
   8 static const char *argv0_path;
   9
  10 char *system_path(const char *path)
  11 {
  12 #ifdef RUNTIME_PREFIX
  13         static const char *prefix;
  14 #else
  15         static const char *prefix = PREFIX;
  16 #endif
  17         struct strbuf d = STRBUF_INIT;
  18
  19         if (is_absolute_path(path))
  20                 return xstrdup(path);
  21
  22 #ifdef RUNTIME_PREFIX
  23         assert(argv0_path);
  24         assert(is_absolute_path(argv0_path));
  25
  26         if (!prefix &&
  27             !(prefix = strip_path_suffix(argv0_path, GIT_EXEC_PATH)) &&
  28             !(prefix = strip_path_suffix(argv0_path, BINDIR)) &&
  29             !(prefix = strip_path_suffix(argv0_path, "git"))) {
  30                 prefix = PREFIX;
  31                 trace_printf("RUNTIME_PREFIX requested, "
  32                                 "but prefix computation failed.  "
  33                                 "Using static fallback '%s'.\n", prefix);
  34         }
  35 #endif
  36
  37         strbuf_addf(&d, "%s/%s", prefix, path);
  38         return strbuf_detach(&d, NULL);
  39 }
  40
  41 void git_extract_argv0_path(const char *argv0)
  42 {
  43         const char *slash;
  44
  45         if (!argv0 || !*argv0)
  46                 return;
  47
  48         slash = find_last_dir_sep(argv0);
  49
  50         if (slash)
  51                 argv0_path = xstrndup(argv0, slash - argv0);
  52 }
  53
  54 void git_set_argv_exec_path(const char *exec_path)
  55 {
  56         argv_exec_path = exec_path;
  57         /*
  58          * Propagate this setting to external programs.
  59          */
  60         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  61 }
  62
  63
  64 /* Returns the highest-priority, location to look for git programs. */
  65 const char *git_exec_path(void)
  66 {
  67         static char *cached_exec_path;
  68
  69         if (argv_exec_path)
  70                 return argv_exec_path;
  71
  72         if (!cached_exec_path) {
  73                 const char *env = getenv(EXEC_PATH_ENVIRONMENT);
  74                 if (env && *env)
  75                         cached_exec_path = xstrdup(env);
  76                 else
  77                         cached_exec_path = system_path(GIT_EXEC_PATH);
  78         }
  79         return cached_exec_path;
  80 }
  81
  82 static void add_path(struct strbuf *out, const char *path)
  83 {
  84         if (path && *path) {
  85                 strbuf_add_absolute_path(out, path);
  86                 strbuf_addch(out, PATH_SEP);
  87         }
  88 }
  89
  90 void setup_path(void)
  91 {
  92         const char *old_path = getenv("PATH");
  93         struct strbuf new_path = STRBUF_INIT;
  94
  95         add_path(&new_path, git_exec_path());
  96
  97         if (old_path)
  98                 strbuf_addstr(&new_path, old_path);
  99         else
 100                 strbuf_addstr(&new_path, _PATH_DEFPATH);
 101
 102         setenv("PATH", new_path.buf, 1);
 103
 104         strbuf_release(&new_path);
 105 }
 106
 107 const char **prepare_git_cmd(struct argv_array *out, const char **argv)
 108 {
 109         argv_array_push(out, "git");
 110         argv_array_pushv(out, argv);
 111         return out->argv;
 112 }
 113
 114 int execv_git_cmd(const char **argv) {
 115         struct argv_array nargv = ARGV_ARRAY_INIT;
 116
 117         prepare_git_cmd(&nargv, argv);
 118         trace_argv_printf(nargv.argv, "trace: exec:");
 119
 120         /* execvp() can only ever return if it fails */
 121         sane_execvp("git", (char **)nargv.argv);
 122
 123         trace_printf("trace: exec failed: %s\n", strerror(errno));
 124
 125         argv_array_clear(&nargv);
 126         return -1;
 127 }
 128
 129
 130 int execl_git_cmd(const char *cmd,...)
 131 {
 132         int argc;
 133         const char *argv[MAX_ARGS + 1];
 134         const char *arg;
 135         va_list param;
 136
 137         va_start(param, cmd);
 138         argv[0] = cmd;
 139         argc = 1;
 140         while (argc < MAX_ARGS) {
 141                 arg = argv[argc++] = va_arg(param, char *);
 142                 if (!arg)
 143                         break;
 144         }
 145         va_end(param);
 146         if (MAX_ARGS <= argc)
 147                 return error("too many args to run %s", cmd);
 148
 149         argv[argc] = NULL;
 150         return execv_git_cmd(argv);
 151 }