exec_cmd.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "quote.h"
   4 #define MAX_ARGS        32
   5
   6 extern char **environ;
   7 static const char *argv_exec_path;
   8 static const char *argv0_path;
   9
  10 const char *system_path(const char *path)
  11 {
  12         if (!is_absolute_path(path) && argv0_path) {
  13                 struct strbuf d = STRBUF_INIT;
  14                 strbuf_addf(&d, "%s/%s", argv0_path, path);
  15                 path = strbuf_detach(&d, NULL);
  16         }
  17         return path;
  18 }
  19
  20 void git_set_argv0_path(const char *path)
  21 {
  22         argv0_path = path;
  23 }
  24
  25 void git_set_argv_exec_path(const char *exec_path)
  26 {
  27         argv_exec_path = exec_path;
  28 }
  29
  30
  31 /* Returns the highest-priority, location to look for git programs. */
  32 const char *git_exec_path(void)
  33 {
  34         const char *env;
  35
  36         if (argv_exec_path)
  37                 return argv_exec_path;
  38
  39         env = getenv(EXEC_PATH_ENVIRONMENT);
  40         if (env && *env) {
  41                 return env;
  42         }
  43
  44         return system_path(GIT_EXEC_PATH);
  45 }
  46
  47 static void add_path(struct strbuf *out, const char *path)
  48 {
  49         if (path && *path) {
  50                 if (is_absolute_path(path))
  51                         strbuf_addstr(out, path);
  52                 else
  53                         strbuf_addstr(out, make_nonrelative_path(path));
  54
  55                 strbuf_addch(out, PATH_SEP);
  56         }
  57 }
  58
  59 void setup_path(void)
  60 {
  61         const char *old_path = getenv("PATH");
  62         struct strbuf new_path = STRBUF_INIT;
  63
  64         add_path(&new_path, argv_exec_path);
  65         add_path(&new_path, getenv(EXEC_PATH_ENVIRONMENT));
  66         add_path(&new_path, system_path(GIT_EXEC_PATH));
  67         add_path(&new_path, argv0_path);
  68
  69         if (old_path)
  70                 strbuf_addstr(&new_path, old_path);
  71         else
  72                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
  73
  74         setenv("PATH", new_path.buf, 1);
  75
  76         strbuf_release(&new_path);
  77 }
  78
  79 const char **prepare_git_cmd(const char **argv)
  80 {
  81         int argc;
  82         const char **nargv;
  83
  84         for (argc = 0; argv[argc]; argc++)
  85                 ; /* just counting */
  86         nargv = xmalloc(sizeof(*nargv) * (argc + 2));
  87
  88         nargv[0] = "git";
  89         for (argc = 0; argv[argc]; argc++)
  90                 nargv[argc + 1] = argv[argc];
  91         nargv[argc + 1] = NULL;
  92         return nargv;
  93 }
  94
  95 int execv_git_cmd(const char **argv) {
  96         const char **nargv = prepare_git_cmd(argv);
  97         trace_argv_printf(nargv, "trace: exec:");
  98
  99         /* execvp() can only ever return if it fails */
 100         execvp("git", (char **)nargv);
 101
 102         trace_printf("trace: exec failed: %s\n", strerror(errno));
 103
 104         free(nargv);
 105         return -1;
 106 }
 107
 108
 109 int execl_git_cmd(const char *cmd,...)
 110 {
 111         int argc;
 112         const char *argv[MAX_ARGS + 1];
 113         const char *arg;
 114         va_list param;
 115
 116         va_start(param, cmd);
 117         argv[0] = cmd;
 118         argc = 1;
 119         while (argc < MAX_ARGS) {
 120                 arg = argv[argc++] = va_arg(param, char *);
 121                 if (!arg)
 122                         break;
 123         }
 124         va_end(param);
 125         if (MAX_ARGS <= argc)
 126                 return error("too many args to run %s", cmd);
 127
 128         argv[argc] = NULL;
 129         return execv_git_cmd(argv);
 130 }