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