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

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2016, Cyril Bur, IBM Corp.
   4  *
   5  * Sending one self a signal should always get delivered.
   6  */
   7
   8 #include <signal.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <sys/types.h>
  13 #include <sys/wait.h>
  14 #include <unistd.h>
  15
  16 #include <altivec.h>
  17
  18 #include "utils.h"
  19
  20 #define MAX_ATTEMPT 500000
  21 #define TIMEOUT 5
  22
  23 extern long signal_self(pid_t pid, int sig);
  24
  25 static sig_atomic_t signaled;
  26 static sig_atomic_t fail;
  27
  28 static void signal_handler(int sig)
  29 {
  30         if (sig == SIGUSR1)
  31                 signaled = 1;
  32         else
  33                 fail = 1;
  34 }
  35
  36 static int test_signal()
  37 {
  38         int i;
  39         struct sigaction act;
  40         pid_t ppid = getpid();
  41         pid_t pid;
  42
  43         act.sa_handler = signal_handler;
  44         act.sa_flags = 0;
  45         sigemptyset(&act.sa_mask);
  46         if (sigaction(SIGUSR1, &act, NULL) < 0) {
  47                 perror("sigaction SIGUSR1");
  48                 exit(1);
  49         }
  50         if (sigaction(SIGALRM, &act, NULL) < 0) {
  51                 perror("sigaction SIGALRM");
  52                 exit(1);
  53         }
  54
  55         /* Don't do this for MAX_ATTEMPT, its simply too long */
  56         for(i  = 0; i < 1000; i++) {
  57                 pid = fork();
  58                 if (pid == -1) {
  59                         perror("fork");
  60                         exit(1);
  61                 }
  62                 if (pid == 0) {
  63                         signal_self(ppid, SIGUSR1);
  64                         exit(1);
  65                 } else {
  66                         alarm(0); /* Disable any pending */
  67                         alarm(2);
  68                         while (!signaled && !fail)
  69                                 asm volatile("": : :"memory");
  70                         if (!signaled) {
  71                                 fprintf(stderr, "Didn't get signal from child\n");
  72                                 FAIL_IF(1); /* For the line number */
  73                         }
  74                         /* Otherwise we'll loop too fast and fork() will eventually fail */
  75                         waitpid(pid, NULL, 0);
  76                 }
  77         }
  78
  79         for (i = 0; i < MAX_ATTEMPT; i++) {
  80                 long rc;
  81
  82                 alarm(0); /* Disable any pending */
  83                 signaled = 0;
  84                 alarm(TIMEOUT);
  85                 rc = signal_self(ppid, SIGUSR1);
  86                 if (rc) {
  87                         fprintf(stderr, "(%d) Fail reason: %d rc=0x%lx",
  88                                         i, fail, rc);
  89                         FAIL_IF(1); /* For the line number */
  90                 }
  91                 while (!signaled && !fail)
  92                         asm volatile("": : :"memory");
  93                 if (!signaled) {
  94                         fprintf(stderr, "(%d) Fail reason: %d rc=0x%lx",
  95                                         i, fail, rc);
  96                         FAIL_IF(1); /* For the line number */
  97                 }
  98         }
  99
 100         return 0;
 101 }
 102
 103 int main(void)
 104 {
 105         test_harness_set_timeout(300);
 106         return test_harness(test_signal, "signal");
 107 }