testcases/open_posix_testsuite/conformance/interfaces/sigaction/22-4.c

/*

 * Copyright (c) 2002-2003, Intel Corporation. All rights reserved.
 * Created by:  rusty.lynch REMOVE-THIS AT intel DOT com
 * This file is licensed under the GPL license.  For the full content
 * of this license, see the COPYING file at the top level of this
 * source tree.

  Test case for assertion #22 of the sigaction system call that verifies
  that if the SA_NODEFER flag is set for a given signal, then when the
  sa_sigaction signal-catching function is entered, then the signal that
  was caught is not added to the signal mask by raising that signal in the
  signal handler and verifying that the handler is reentered.

  Steps:
  1. Fork a new process
  2. (parent) wait for child
  3. (child) Setup a signal handler for SIGCHLD with SA_NODEFER set
     in the sa_flags field
  4. (child) raise SIGCHLD
  5. (child, signal handler) increment handler count
  6. (child, signal handler) if count is 1 then raise SIGCHLD
  7. (child, signal handler) if count is 1 then set error variable
  8. (child) if error is set then return -1, else return 0
  6. (parent - returning from wait) If child returned 0 then exit 0,
     otherwise exit -1.
*/


#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <unistd.h>
#include "posixtest.h"

int handler_count = 0;

void handler(int signo)
{
	static int inside_handler = 0;

	printf("SIGCHLD caught\n");
	if (inside_handler) {
		printf("Signal caught while inside handler\n");
		exit(0);
	}

	inside_handler++;
	handler_count++;

	if (handler_count == 1) {
		printf("Raising SIGCHLD\n");
		raise(SIGCHLD);
		printf("Returning from raising SIGCHLD\n");
	}

	inside_handler--;
}

int main(void)
{
	if (fork() == 0) {
		/* child */

		struct sigaction act;

		act.sa_handler = handler;
		act.sa_flags = SA_NODEFER;
		sigemptyset(&act.sa_mask);
		if (sigaction(SIGCHLD, &act, 0) == -1) {
			perror("Unexpected error while attempting to "
			       "setup test pre-conditions");
			return PTS_UNRESOLVED;
		}

		if (raise(SIGCHLD) == -1) {
			perror("Unexpected error while attempting to "
			       "setup test pre-conditions");
			return PTS_UNRESOLVED;
		}

		return PTS_FAIL;
	} else {
		int s;

		/* parent */
		if (wait(&s) == -1) {
			perror("Unexpected error while setting up test "
			       "pre-conditions");
			return PTS_UNRESOLVED;
		}

		if (!WEXITSTATUS(s)) {
			printf("Test PASSED\n");
			return PTS_PASS;
		}
	}

	printf("Test FAILED\n");
	return PTS_FAIL;
}