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         static const char *prefix = PREFIX;
  13         struct strbuf d = STRBUF_INIT;
  14
  15         if (is_absolute_path(path))
  16                 return path;
  17
  18         strbuf_addf(&d, "%s/%s", prefix, path);
  19         path = strbuf_detach(&d, NULL);
  20         return path;
  21 }
  22
  23 const char *git_extract_argv0_path(const char *argv0)
  24 {
  25         const char *slash;
  26
  27         if (!argv0 || !*argv0)
  28                 return NULL;
  29         slash = argv0 + strlen(argv0);
  30
  31         while (argv0 <= slash && !is_dir_sep(*slash))
  32                 slash--;
  33
  34         if (slash >= argv0) {
  35                 argv0_path = xstrndup(argv0, slash - argv0);
  36                 return slash + 1;
  37         }
  38
  39         return argv0;
  40 }
  41
  42 void git_set_argv_exec_path(const char *exec_path)
  43 {
  44         argv_exec_path = exec_path;
  45 }
  46
  47
  48 /* Returns the highest-priority, location to look for git programs. */
  49 const char *git_exec_path(void)
  50 {
  51         const char *env;
  52
  53         if (argv_exec_path)
  54                 return argv_exec_path;
  55
  56         env = getenv(EXEC_PATH_ENVIRONMENT);
  57         if (env && *env) {
  58                 return env;
  59         }
  60
  61         return system_path(GIT_EXEC_PATH);
  62 }
  63
  64 static void add_path(struct strbuf *out, const char *path)
  65 {
  66         if (path && *path) {
  67                 if (is_absolute_path(path))
  68                         strbuf_addstr(out, path);
  69                 else
  70                         strbuf_addstr(out, make_nonrelative_path(path));
  71
  72                 strbuf_addch(out, PATH_SEP);
  73         }
  74 }
  75
  76 void setup_path(void)
  77 {
  78         const char *old_path = getenv("PATH");
  79         struct strbuf new_path = STRBUF_INIT;
  80
  81         add_path(&new_path, git_exec_path());
  82         add_path(&new_path, argv0_path);
  83
  84         if (old_path)
  85                 strbuf_addstr(&new_path, old_path);
  86         else
  87                 strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
  88
  89         setenv("PATH", new_path.buf, 1);
  90
  91         strbuf_release(&new_path);
  92 }
  93
  94 const char **prepare_git_cmd(const char **argv)
  95 {
  96         int argc;
  97         const char **nargv;
  98
  99         for (argc = 0; argv[argc]; argc++)
 100                 ; /* just counting */
 101         nargv = xmalloc(sizeof(*nargv) * (argc + 2));
 102
 103         nargv[0] = "git";
 104         for (argc = 0; argv[argc]; argc++)
 105                 nargv[argc + 1] = argv[argc];
 106         nargv[argc + 1] = NULL;
 107         return nargv;
 108 }
 109
 110 int execv_git_cmd(const char **argv) {
 111         const char **nargv = prepare_git_cmd(argv);
 112         trace_argv_printf(nargv, "trace: exec:");
 113
 114         /* execvp() can only ever return if it fails */
 115         execvp("git", (char **)nargv);
 116
 117         trace_printf("trace: exec failed: %s\n", strerror(errno));
 118
 119         free(nargv);
 120         return -1;
 121 }
 122
 123
 124 int execl_git_cmd(const char *cmd,...)
 125 {
 126         int argc;
 127         const char *argv[MAX_ARGS + 1];
 128         const char *arg;
 129         va_list param;
 130
 131         va_start(param, cmd);
 132         argv[0] = cmd;
 133         argc = 1;
 134         while (argc < MAX_ARGS) {
 135                 arg = argv[argc++] = va_arg(param, char *);
 136                 if (!arg)
 137                         break;
 138         }
 139         va_end(param);
 140         if (MAX_ARGS <= argc)
 141                 return error("too many args to run %s", cmd);
 142
 143         argv[argc] = NULL;
 144         return execv_git_cmd(argv);
 145 }