src/regression/daemon-failure.c

   1 // commit: 19e35c500bd2b5e6146e42705ab9b69c155a2006 2011-02-17
   2 // commit: 187fe29d5b89644b68cade75a34257a1c32a75f6 2011-02-17
   3 // non-standard musl specific behaviour
   4 // daemon should not fork in case of failure of chdir or open, but
   5 // since setsid and fork may still fail after fork this behaviour
   6 // is not very useful
   7 #define _DEFAULT_SOURCE 1
   8 #define _BSD_SOURCE 1
   9 #include <string.h>
  10 #include <errno.h>
  11 #include <sys/wait.h>
  12 #include <fcntl.h>
  13 #include <unistd.h>
  14 #include "test.h"
  15
  16 int daemon(int, int);
  17
  18 int main(void)
  19 {
  20         int r, pid, fd[2], fdout, s;
  21         char c;
  22
  23         r = pipe(fd);
  24         if (r == -1) {
  25                 t_error("pipe failed: %s\n", strerror(errno));
  26                 return 1;
  27         }
  28         fdout = dup(1);
  29         if (fdout == -1) {
  30                 t_error("dup(1) failed: %s\n", strerror(errno));
  31                 return 1;
  32         }
  33         r = fork();
  34         if (r == -1) {
  35                 t_error("fork failed: %s\n", strerror(errno));
  36                 return 1;
  37         }
  38
  39         if (r == 0) {
  40                 /* exhausting all fds makes open("/dev/null") fail in daemon */
  41                 t_fdfill();
  42                 pid = getpid();
  43                 errno = 0;
  44                 r = daemon(0, 0);
  45                 if (dup2(fdout,1) == -1) {
  46                         write(fdout, "ERROR:\n", 7);
  47                         t_error("failed to dup pipe fd for communicating results: %s\n", strerror(errno));
  48                 }
  49                 if (r != -1)
  50                         t_error("daemon should have failed\n");
  51                 if (errno != EMFILE)
  52                         t_error("daemon should have failed with %d [EMFILE] got %d [%s]\n", EMFILE, errno, strerror(errno));
  53                 if (getpid() != pid || getppid() == 1)
  54                         t_error("daemon forked despite failure: ppid is %d, pid is %d, old pid is %d\n",
  55                                 getppid(), getpid(), pid);
  56                 if (write(fd[1], "1" + !t_status, 1) != 1)
  57                         t_error("write failed: %s\n", strerror(errno));
  58                 return t_status;
  59         }
  60         close(fd[1]);
  61         if (waitpid(r, &s, 0) != r)
  62                 t_error("waitpid failed: %s\n", strerror(errno));
  63         else if (!WIFEXITED(s))
  64                 t_error("child exited abnormally (signal %d)\n", WIFSIGNALED(s) ? WTERMSIG(s) : 0);
  65         else if (WEXITSTATUS(s))
  66                 t_error("child exited with %d\n", WEXITSTATUS(s));
  67         r = read(fd[0], &c, 1);
  68         if (r == -1)
  69                 t_error("read failed: %s\n", strerror(errno));
  70         else if (r == 0)
  71                 t_error("read failed: child did not send its exit status\n");
  72         else if (c != 0)
  73                 t_error("child failed\n");
  74
  75         return t_status;
  76 }