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          * Propagate this setting to external programs.
  30          */
  31         setenv(EXEC_PATH_ENVIRONMENT, exec_path, 1);
  32 }
  33
  34
  35 /* Returns the highest-priority, location to look for git programs. */
  36 const char *git_exec_path(void)
  37 {
  38         const char *env;
  39
  40         if (argv_exec_path)
  41                 return argv_exec_path;
  42
  43         env = getenv(EXEC_PATH_ENVIRONMENT);
  44         if (env && *env) {
  45                 return env;
  46         }
  47
  48         return system_path(GIT_EXEC_PATH);
  49 }
  50
  51 static void add_path(struct strbuf *out, const char *path)
  52 {
  53         if (path && *path) {
  54                 if (is_absolute_path(path))
  55                         strbuf_addstr(out, path);
  56                 else
  57                         strbuf_addstr(out, make_nonrelative_path(path));
  58
  59                 strbuf_addch(out, PATH_SEP);
  60         }
  61 }
  62
  63 void setup_path(void)
  64 {
  65         const char *old_path = getenv("PATH");
  66         struct strbuf new_path = STRBUF_INIT;
  67
  68         add_path(&new_path, argv_exec_path);
  69         add_path(&new_path, getenv(EXEC_PATH_ENVIRONMENT));
  70         add_path(&new_path, system_path(GIT_EXEC_PATH));
  71         add_path(&new_path, argv0_path);
  72
  73         if (old_path)
  74                 strbuf_addstr(&new_path, old_path);
  75         else
  76                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
  77
  78         setenv("PATH", new_path.buf, 1);
  79
  80         strbuf_release(&new_path);
  81 }
  82
  83 const char **prepare_git_cmd(const char **argv)
  84 {
  85         int argc;
  86         const char **nargv;
  87
  88         for (argc = 0; argv[argc]; argc++)
  89                 ; /* just counting */
  90         nargv = xmalloc(sizeof(*nargv) * (argc + 2));
  91
  92         nargv[0] = "git";
  93         for (argc = 0; argv[argc]; argc++)
  94                 nargv[argc + 1] = argv[argc];
  95         nargv[argc + 1] = NULL;
  96         return nargv;
  97 }
  98
  99 int execv_git_cmd(const char **argv) {
 100         const char **nargv = prepare_git_cmd(argv);
 101         trace_argv_printf(nargv, "trace: exec:");
 102
 103         /* execvp() can only ever return if it fails */
 104         execvp("git", (char **)nargv);
 105
 106         trace_printf("trace: exec failed: %s\n", strerror(errno));
 107
 108         free(nargv);
 109         return -1;
 110 }
 111
 112
 113 int execl_git_cmd(const char *cmd,...)
 114 {
 115         int argc;
 116         const char *argv[MAX_ARGS + 1];
 117         const char *arg;
 118         va_list param;
 119
 120         va_start(param, cmd);
 121         argv[0] = cmd;
 122         argc = 1;
 123         while (argc < MAX_ARGS) {
 124                 arg = argv[argc++] = va_arg(param, char *);
 125                 if (!arg)
 126                         break;
 127         }
 128         va_end(param);
 129         if (MAX_ARGS <= argc)
 130                 return error("too many args to run %s", cmd);
 131
 132         argv[argc] = NULL;
 133         return execv_git_cmd(argv);
 134 }