LXR linux/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
  23extern long signal_self(pid_t pid, int sig);
  24
  25static sig_atomic_t signaled;
  26static sig_atomic_t fail;
  27
  28static void signal_handler(int sig)
  29{
  30        if (sig == SIGUSR1)
  31                signaled = 1;
  32        else
  33                fail = 1;
  34}
  35
  36static 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
 103int main(void)
 104{
 105        test_harness_set_timeout(300);
 106        return test_harness(test_signal, "signal");
 107}
 108