lib/ccan/read_write_all/test/run-read_all.c

   1 /* FIXME: Do something tricky to ensure we really do loop in read_all. */
   2
   3 #include <ccan/read_write_all/read_write_all.h>
   4 #include <ccan/read_write_all/read_write_all.c>
   5 #include <ccan/tap/tap.h>
   6 #include <unistd.h>
   7 #include <sys/types.h>
   8 #include <signal.h>
   9 #include <sys/wait.h>
  10 #include <limits.h>
  11 #include <err.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14
  15 static volatile int sigcount;
  16 static int p2c[2], c2p[2];
  17 static void got_signal(int sig)
  18 {
  19         char c = 0;
  20         if (write(p2c[1], &c, 1) == 1)
  21                 sigcount++;
  22 }
  23
  24 /* < PIPE_BUF *will* be atomic.  But > PIPE_BUF only *might* be non-atomic. */
  25 #define BUFSZ (1024*1024)
  26
  27 int main(int argc, char *argv[])
  28 {
  29         char *buffer;
  30         char c = 0;
  31         int status;
  32         pid_t child;
  33
  34         buffer = calloc(BUFSZ, 2);
  35         plan_tests(6);
  36
  37         /* We fork and torture parent. */
  38         if (pipe(p2c) != 0 || pipe(c2p) != 0)
  39                 err(1, "pipe");
  40         child = fork();
  41
  42         if (!child) {
  43                 close(p2c[1]);
  44                 close(c2p[0]);
  45                 /* Child.  Make sure parent ready, then write in two parts. */
  46                 if (read(p2c[0], &c, 1) != 1)
  47                         exit(1);
  48                 memset(buffer, 0xff, BUFSZ*2);
  49                 if (!write_all(c2p[1], buffer, BUFSZ))
  50                         exit(2);
  51                 if (kill(getppid(), SIGUSR1) != 0)
  52                         exit(3);
  53                 /* Make sure they get signal. */
  54                 if (read(p2c[0], &c, 1) != 1)
  55                         exit(4);
  56                 if (write(c2p[1], buffer, BUFSZ) != BUFSZ)
  57                         exit(5);
  58                 exit(0);
  59         }
  60         if (child == -1)
  61                 err(1, "forking");
  62
  63         close(p2c[0]);
  64         close(c2p[1]);
  65         signal(SIGUSR1, got_signal);
  66         ok1(write(p2c[1], &c, 1) == 1);
  67         ok1(read_all(c2p[0], buffer, BUFSZ*2));
  68         ok1(memchr(buffer, 0, BUFSZ*2) == NULL);
  69         ok1(sigcount == 1);
  70         ok1(wait(&status) == child);
  71         ok(WIFEXITED(status) && WEXITSTATUS(status) == 0,
  72            "WIFEXITED(status) = %u, WEXITSTATUS(status) = %u",
  73            WIFEXITED(status), WEXITSTATUS(status));
  74         free(buffer);
  75         return exit_status();
  76 }