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
   9 #ifdef RUNTIME_PREFIX
  10 static const char *argv0_path;
  11
  12 static const char *system_prefix(void)
  13 {
  14         static const char *prefix;
  15
  16         assert(argv0_path);
  17         assert(is_absolute_path(argv0_path));
  18
  19         if (!prefix &&
  20             !(prefix = strip_path_suffix(argv0_path, GIT_EXEC_PATH)) &&
  21             !(prefix = strip_path_suffix(argv0_path, BINDIR)) &&
  22             !(prefix = strip_path_suffix(argv0_path, "git"))) {
  23                 prefix = PREFIX;
  24                 trace_printf("RUNTIME_PREFIX requested, "
  25                                 "but prefix computation failed.  "
  26                                 "Using static fallback '%s'.\n", prefix);
  27         }
  28         return prefix;
  29 }
  30
  31 void git_extract_argv0_path(const char *argv0)
  32 {
  33         const char *slash;
  34
  35         if (!argv0 || !*argv0)
  36                 return;
  37
  38         slash = find_last_dir_sep(argv0);
  39
  40         if (slash)
  41                 argv0_path = xstrndup(argv0, slash - argv0);
  42 }
  43
  44 #else
  45
  46 static const char *system_prefix(void)
  47 {
  48         return PREFIX;
  49 }
  50
  51 void git_extract_argv0_path(const char *argv0)
  52 {
  53 }
  54
  55 #endif /* RUNTIME_PREFIX */
  56
  57 char *system_path(const char *path)
  58 {
  59         struct strbuf d = STRBUF_INIT;
  60
  61         if (is_absolute_path(path))
  62                 return xstrdup(path);
  63
  64         strbuf_addf(&d, "%s/%s", system_prefix(), path);
  65         return strbuf_detach(&d, NULL);
  66 }
  67
  68 void git_set_argv_exec_path(const char *exec_path)
  69 {
  70         argv_exec_path = exec_path;
  71         /*
  72          * Propagate this setting to external programs.
  73          */
  74         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  75 }
  76
  77
  78 /* Returns the highest-priority, location to look for git programs. */
  79 const char *git_exec_path(void)
  80 {
  81         static char *cached_exec_path;
  82
  83         if (argv_exec_path)
  84                 return argv_exec_path;
  85
  86         if (!cached_exec_path) {
  87                 const char *env = getenv(EXEC_PATH_ENVIRONMENT);
  88                 if (env && *env)
  89                         cached_exec_path = xstrdup(env);
  90                 else
  91                         cached_exec_path = system_path(GIT_EXEC_PATH);
  92         }
  93         return cached_exec_path;
  94 }
  95
  96 static void add_path(struct strbuf *out, const char *path)
  97 {
  98         if (path && *path) {
  99                 strbuf_add_absolute_path(out, path);
 100                 strbuf_addch(out, PATH_SEP);
 101         }
 102 }
 103
 104 void setup_path(void)
 105 {
 106         const char *old_path = getenv("PATH");
 107         struct strbuf new_path = STRBUF_INIT;
 108
 109         add_path(&new_path, git_exec_path());
 110
 111         if (old_path)
 112                 strbuf_addstr(&new_path, old_path);
 113         else
 114                 strbuf_addstr(&new_path, _PATH_DEFPATH);
 115
 116         setenv("PATH", new_path.buf, 1);
 117
 118         strbuf_release(&new_path);
 119 }
 120
 121 const char **prepare_git_cmd(struct argv_array *out, const char **argv)
 122 {
 123         argv_array_push(out, "git");
 124         argv_array_pushv(out, argv);
 125         return out->argv;
 126 }
 127
 128 int execv_git_cmd(const char **argv) {
 129         struct argv_array nargv = ARGV_ARRAY_INIT;
 130
 131         prepare_git_cmd(&nargv, argv);
 132         trace_argv_printf(nargv.argv, "trace: exec:");
 133
 134         /* execvp() can only ever return if it fails */
 135         sane_execvp("git", (char **)nargv.argv);
 136
 137         trace_printf("trace: exec failed: %s\n", strerror(errno));
 138
 139         argv_array_clear(&nargv);
 140         return -1;
 141 }
 142
 143
 144 int execl_git_cmd(const char *cmd,...)
 145 {
 146         int argc;
 147         const char *argv[MAX_ARGS + 1];
 148         const char *arg;
 149         va_list param;
 150
 151         va_start(param, cmd);
 152         argv[0] = cmd;
 153         argc = 1;
 154         while (argc < MAX_ARGS) {
 155                 arg = argv[argc++] = va_arg(param, char *);
 156                 if (!arg)
 157                         break;
 158         }
 159         va_end(param);
 160         if (MAX_ARGS <= argc)
 161                 return error("too many args to run %s", cmd);
 162
 163         argv[argc] = NULL;
 164         return execv_git_cmd(argv);
 165 }