nsz Git - musl/blob - src/process/system.c

   1 #include <unistd.h>
   2 #include <fcntl.h>
   3 #include <signal.h>
   4 #include <sys/wait.h>
   5 #include <errno.h>
   6
   7 int system(const char *cmd)
   8 {
   9         pid_t pid;
  10         sigset_t old, new;
  11         struct sigaction sa, oldint, oldquit;
  12         int status;
  13
  14         if (!cmd) return 1;
  15
  16         sa.sa_handler = SIG_IGN;
  17         sigemptyset(&sa.sa_mask);
  18         sa.sa_flags = 0;
  19
  20         sigaction(SIGINT, &sa, &oldint);
  21         sigaction(SIGQUIT, &sa, &oldquit);
  22         sigaddset(&sa.sa_mask, SIGCHLD);
  23         sigprocmask(SIG_BLOCK, &new, &old);
  24
  25         pid = fork();
  26         if (pid <= 0) {
  27                 sigaction(SIGINT, &oldint, NULL);
  28                 sigaction(SIGQUIT, &oldquit, NULL);
  29                 sigprocmask(SIG_SETMASK, &old, NULL);
  30                 if (pid == 0) {
  31                         execl("/bin/sh", "sh", "-c", cmd, (char *)0);
  32                         _exit(127);
  33                 }
  34                 return -1;
  35         }
  36         while (waitpid(pid, &status, 0) == -1)
  37                 if (errno != EINTR) {
  38                         status = -1;
  39                         break;
  40                 }
  41         sigaction(SIGINT, &oldint, NULL);
  42         sigaction(SIGQUIT, &oldquit, NULL);
  43         sigprocmask(SIG_SETMASK, &old, NULL);
  44         return status;
  45 }