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 }
108