silentbob/silentbob-1.4.1/gclib/gclib_c/dfork.c

   1 /*
   2  * (c) Oleg Puchinin 2006
   3  * graycardinalster@gmail.com
   4  *
   5  */
   6
   7 #include <gclib_c.h>
   8 #define __export
   9
  10 __export int Dfork (char *exec, int *fd_in, int *fd_out, int *fd_err)
  11 {
  12         int ret;
  13         int pipe_in[2];
  14         int pipe_out[2];
  15         int pipe_err[2];
  16
  17         if (fd_in)
  18                 pipe (pipe_in);
  19
  20         if (fd_out)
  21                 pipe (pipe_out);
  22
  23         if (fd_err)
  24                 pipe (pipe_err);
  25
  26         ret = fork ();
  27         if (ret < 0) {
  28                 if (fd_in)
  29                         close_pipe (pipe_in);
  30
  31                 if (fd_out)
  32                         close_pipe (pipe_out);
  33
  34                 if (fd_err)
  35                         close_pipe (pipe_err);
  36
  37                 return ret;
  38         }
  39
  40         if (ret == 0) {
  41                 if (fd_in) {
  42                         dup2 (pipe_in[0], fileno (stdin));
  43                         close (pipe_in[1]);
  44                 }
  45
  46                 if (fd_out) {
  47                         dup2 (pipe_out[1], fileno (stdout));
  48                         close (pipe_out[0]);
  49                 }
  50
  51                 if (fd_err) {
  52                         dup2 (pipe_err[1], fileno (stderr));
  53                         close (pipe_err[0]);
  54                 }
  55
  56                 if (exec)
  57                         execlp ("sh", "sh", "-c", exec, NULL);
  58
  59                 return 0;
  60         }
  61
  62         if (fd_in) {
  63                 close (pipe_in[0]);
  64                 *fd_in = pipe_in[1];
  65         }
  66
  67         if (fd_out) {
  68                 close (pipe_out[1]);
  69                 *fd_out = pipe_out[0];
  70         }
  71
  72         if (fd_err) {
  73                 close (pipe_err[1]);
  74                 *fd_err = pipe_err[0];
  75         }
  76
  77         return ret;
  78 }
  79