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;
  67
  68         strbuf_init(&new_path, 0);
  69
  70         add_path(&new_path, argv_exec_path);
  71         add_path(&new_path, getenv(EXEC_PATH_ENVIRONMENT));
  72         add_path(&new_path, system_path(GIT_EXEC_PATH));
  73         add_path(&new_path, argv0_path);
  74
  75         if (old_path)
  76                 strbuf_addstr(&new_path, old_path);
  77         else
  78                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
  79
  80         setenv("PATH", new_path.buf, 1);
  81
  82         strbuf_release(&new_path);
  83 }
  84
  85 const char **prepare_git_cmd(const char **argv)
  86 {
  87         int argc;
  88         const char **nargv;
  89
  90         for (argc = 0; argv[argc]; argc++)
  91                 ; /* just counting */
  92         nargv = xmalloc(sizeof(*nargv) * (argc + 2));
  93
  94         nargv[0] = "git";
  95         for (argc = 0; argv[argc]; argc++)
  96                 nargv[argc + 1] = argv[argc];
  97         nargv[argc + 1] = NULL;
  98         return nargv;
  99 }
 100
 101 int execv_git_cmd(const char **argv) {
 102         const char **nargv = prepare_git_cmd(argv);
 103         trace_argv_printf(nargv, "trace: exec:");
 104
 105         /* execvp() can only ever return if it fails */
 106         execvp("git", (char **)nargv);
 107
 108         trace_printf("trace: exec failed: %s\n", strerror(errno));
 109
 110         free(nargv);
 111         return -1;
 112 }
 113
 114
 115 int execl_git_cmd(const char *cmd,...)
 116 {
 117         int argc;
 118         const char *argv[MAX_ARGS + 1];
 119         const char *arg;
 120         va_list param;
 121
 122         va_start(param, cmd);
 123         argv[0] = cmd;
 124         argc = 1;
 125         while (argc < MAX_ARGS) {
 126                 arg = argv[argc++] = va_arg(param, char *);
 127                 if (!arg)
 128                         break;
 129         }
 130         va_end(param);
 131         if (MAX_ARGS <= argc)
 132                 return error("too many args to run %s", cmd);
 133
 134         argv[argc] = NULL;
 135         return execv_git_cmd(argv);
 136 }