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 const char *git_extract_argv0_path(const char *argv0)
  42 {
  43         const char *slash;
  44
  45         if (!argv0 || !*argv0)
  46                 return NULL;
  47         slash = argv0 + strlen(argv0);
  48
  49         while (argv0 <= slash && !is_dir_sep(*slash))
  50                 slash--;
  51
  52         if (slash >= argv0) {
  53                 argv0_path = xstrndup(argv0, slash - argv0);
  54                 return slash + 1;
  55         }
  56
  57         return argv0;
  58 }
  59
  60 void git_set_argv_exec_path(const char *exec_path)
  61 {
  62         argv_exec_path = exec_path;
  63         /*
  64          * Propagate this setting to external programs.
  65          */
  66         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  67 }
  68
  69
  70 /* Returns the highest-priority, location to look for git programs. */
  71 const char *git_exec_path(void)
  72 {
  73         const char *env;
  74
  75         if (argv_exec_path)
  76                 return argv_exec_path;
  77
  78         env = getenv(EXEC_PATH_ENVIRONMENT);
  79         if (env && *env) {
  80                 return env;
  81         }
  82
  83         return system_path(GIT_EXEC_PATH);
  84 }
  85
  86 static void add_path(struct strbuf *out, const char *path)
  87 {
  88         if (path && *path) {
  89                 strbuf_add_absolute_path(out, path);
  90                 strbuf_addch(out, PATH_SEP);
  91         }
  92 }
  93
  94 void setup_path(void)
  95 {
  96         const char *old_path = getenv("PATH");
  97         struct strbuf new_path = STRBUF_INIT;
  98
  99         add_path(&new_path, git_exec_path());
 100
 101         if (old_path)
 102                 strbuf_addstr(&new_path, old_path);
 103         else
 104                 strbuf_addstr(&new_path, _PATH_DEFPATH);
 105
 106         setenv("PATH", new_path.buf, 1);
 107
 108         strbuf_release(&new_path);
 109 }
 110
 111 const char **prepare_git_cmd(struct argv_array *out, const char **argv)
 112 {
 113         argv_array_push(out, "git");
 114         argv_array_pushv(out, argv);
 115         return out->argv;
 116 }
 117
 118 int execv_git_cmd(const char **argv) {
 119         struct argv_array nargv = ARGV_ARRAY_INIT;
 120
 121         prepare_git_cmd(&nargv, argv);
 122         trace_argv_printf(nargv.argv, "trace: exec:");
 123
 124         /* execvp() can only ever return if it fails */
 125         sane_execvp("git", (char **)nargv.argv);
 126
 127         trace_printf("trace: exec failed: %s\n", strerror(errno));
 128
 129         argv_array_clear(&nargv);
 130         return -1;
 131 }
 132
 133
 134 int execl_git_cmd(const char *cmd,...)
 135 {
 136         int argc;
 137         const char *argv[MAX_ARGS + 1];
 138         const char *arg;
 139         va_list param;
 140
 141         va_start(param, cmd);
 142         argv[0] = cmd;
 143         argc = 1;
 144         while (argc < MAX_ARGS) {
 145                 arg = argv[argc++] = va_arg(param, char *);
 146                 if (!arg)
 147                         break;
 148         }
 149         va_end(param);
 150         if (MAX_ARGS <= argc)
 151                 return error("too many args to run %s", cmd);
 152
 153         argv[argc] = NULL;
 154         return execv_git_cmd(argv);
 155 }