tools/testing/selftests/powerpc/signal/signal.c

   1 /*
   2  * Copyright 2016, Cyril Bur, IBM Corp.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  *
   9  * Sending one self a signal should always get delivered.
  10  */
  11
  12 #include <signal.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <sys/types.h>
  17 #include <sys/wait.h>
  18 #include <unistd.h>
  19
  20 #include <altivec.h>
  21
  22 #include "utils.h"
  23
  24 #define MAX_ATTEMPT 500000
  25 #define TIMEOUT 5
  26
  27 extern long signal_self(pid_t pid, int sig);
  28
  29 static sig_atomic_t signaled;
  30 static sig_atomic_t fail;
  31
  32 static void signal_handler(int sig)
  33 {
  34         if (sig == SIGUSR1)
  35                 signaled = 1;
  36         else
  37                 fail = 1;
  38 }
  39
  40 static int test_signal()
  41 {
  42         int i;
  43         struct sigaction act;
  44         pid_t ppid = getpid();
  45         pid_t pid;
  46
  47         act.sa_handler = signal_handler;
  48         act.sa_flags = 0;
  49         sigemptyset(&act.sa_mask);
  50         if (sigaction(SIGUSR1, &act, NULL) < 0) {
  51                 perror("sigaction SIGUSR1");
  52                 exit(1);
  53         }
  54         if (sigaction(SIGALRM, &act, NULL) < 0) {
  55                 perror("sigaction SIGALRM");
  56                 exit(1);
  57         }
  58
  59         /* Don't do this for MAX_ATTEMPT, its simply too long */
  60         for(i  = 0; i < 1000; i++) {
  61                 pid = fork();
  62                 if (pid == -1) {
  63                         perror("fork");
  64                         exit(1);
  65                 }
  66                 if (pid == 0) {
  67                         signal_self(ppid, SIGUSR1);
  68                         exit(1);
  69                 } else {
  70                         alarm(0); /* Disable any pending */
  71                         alarm(2);
  72                         while (!signaled && !fail)
  73                                 asm volatile("": : :"memory");
  74                         if (!signaled) {
  75                                 fprintf(stderr, "Didn't get signal from child\n");
  76                                 FAIL_IF(1); /* For the line number */
  77                         }
  78                         /* Otherwise we'll loop too fast and fork() will eventually fail */
  79                         waitpid(pid, NULL, 0);
  80                 }
  81         }
  82
  83         for (i = 0; i < MAX_ATTEMPT; i++) {
  84                 long rc;
  85
  86                 alarm(0); /* Disable any pending */
  87                 signaled = 0;
  88                 alarm(TIMEOUT);
  89                 rc = signal_self(ppid, SIGUSR1);
  90                 if (rc) {
  91                         fprintf(stderr, "(%d) Fail reason: %d rc=0x%lx",
  92                                         i, fail, rc);
  93                         FAIL_IF(1); /* For the line number */
  94                 }
  95                 while (!signaled && !fail)
  96                         asm volatile("": : :"memory");
  97                 if (!signaled) {
  98                         fprintf(stderr, "(%d) Fail reason: %d rc=0x%lx",
  99                                         i, fail, rc);
 100                         FAIL_IF(1); /* For the line number */
 101                 }
 102         }
 103
 104         return 0;
 105 }
 106
 107 int main(void)
 108 {
 109         test_harness_set_timeout(300);
 110         return test_harness(test_signal, "signal");
 111 }