pie.c

   1 /* Cycript - The Truly Universal Scripting Language
   2  * Copyright (C) 2009-2016  Jay Freeman (saurik)
   3 */
   4
   5 /* GNU Affero General Public License, Version 3 {{{ */
   6 /*
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 **/
  20 /* }}} */
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include <dlfcn.h>
  27 #include <unistd.h>
  28
  29 static void fail(const char *error) {
  30     perror(error);
  31     exit(1);
  32 }
  33
  34 int main(int argc, const char *argv[]) {
  35     char buffer[1024];
  36     if (readlink("/proc/self/exe", buffer, sizeof(buffer)) == -1)
  37         fail("cannot read from /proc/self/exe");
  38
  39     char *slash = strrchr(buffer, '/');
  40     if (slash == NULL)
  41         fail("could not find executable folder");
  42
  43     strcpy(slash + 1, "cycript-a32");
  44     void *handle = dlopen(buffer, RTLD_LAZY);
  45     if (handle == NULL) {
  46         fprintf(stderr, "%s\n", dlerror());
  47         fail("could not load actual executable");
  48     }
  49
  50     int (*$main)(int argc, const char *argv[]);
  51     $main = (int (*)(int, const char *[])) dlsym(handle, "main");
  52     if ($main == NULL)
  53         fail("could not locale main symbol");
  54
  55     return $main(argc, argv);
  56 }