none/tests/exec-sigmask.c

   1 #include <unistd.h>
   2 #include <signal.h>
   3 #include <errno.h>
   4 #include <string.h>
   5 #include <stdio.h>
   6 #include <sys/wait.h>
   7 #include <sys/types.h>
   8 #include <stdlib.h>
   9
  10 static void do_exec(const char *path, const char *arg, const sigset_t *mask)
  11 {
  12         pid_t pid;
  13         int status;
  14
  15         pid = fork();
  16         if (pid == -1) {
  17                 perror("fork");
  18                 exit(1);
  19         }
  20         if (pid == 0) {
  21                 sigprocmask(SIG_SETMASK, mask, NULL);
  22                 execl(path, path, arg, (char *) NULL);
  23
  24                 fprintf(stderr, "FAILED: execl failed with %s\n",
  25                         strerror(errno));
  26         } else {
  27                 int ret;
  28                 do
  29                         ret = waitpid(pid, &status, 0);
  30                 while(ret == -1 && errno == EINTR);
  31                 if (ret != pid) {
  32                         perror("waitpid");
  33                         exit(1);
  34                 }
  35                 if (status != 0) {
  36                         fprintf(stderr, "child exec failed\n");
  37                         exit(1);
  38                 }
  39         }
  40 }
  41
  42 int main(int argc, char **argv)
  43 {
  44         if (argc == 1) {
  45                 sigset_t mask;
  46
  47                 sigfillset(&mask);
  48                 do_exec(argv[0], "full", &mask);
  49
  50                 sigemptyset(&mask);
  51                 do_exec(argv[0], "empty", &mask);
  52         } else {
  53                 sigset_t mask;
  54                 int i;
  55                 int empty;
  56
  57                 if (strcmp(argv[1], "full") == 0)
  58                         empty = 0;
  59                 else if (strcmp(argv[1], "empty") == 0)
  60                         empty = 1;
  61                 else {
  62                         fprintf(stderr, "empty or full?\n");
  63                         exit(1);
  64                 }
  65
  66                 sigprocmask(SIG_SETMASK, NULL, &mask);
  67
  68                 for(i = 1; i < NSIG; i++) {
  69                         if (i == SIGKILL || i == SIGSTOP)
  70                                 continue;
  71
  72                         if (empty) {
  73                                 if (sigismember(&mask, i))
  74                                         printf("empty: signal %d added to mask\n", i);
  75                         } else {
  76                                 if (!sigismember(&mask, i))
  77                                         printf("full: signal %d missing from mask\n", i);
  78                         }
  79                 }
  80         }
  81
  82         return 0;
  83 }