/* testfork.c
 *
 * Demonstrates that using area's for shared memory across fork()
 * fails on BeOS.
 *
 * Build using 
 *
 * gcc -g -O0 -Wall -o testfork testfork.c
 *
 */
 
#include <kernel/OS.h>
#include <stdio.h>
#include <unistd.h>

static int *x = NULL;
static sem_id the_lock = -1;

static int increment(int n)
{
	snooze(1000);
	return n + 1;
}

#define KIDS      5
#define LOOPS   100

static void test_fork(void)
{
	int j = 0;
	pid_t pids[KIDS];
	
	*x = 0;	
	printf("x is at %p\n", x);
	
	for (j = 0; j < KIDS; j++) {
		pids[j] = fork();
		if (pids[j] < 0) {
			printf("Error in fork()\n");
			exit(-1);
		} else if (pids[j] == 0) {
			int i;
			printf("child %8ld started: x = %p, *x = %d\n", 
			       find_thread(NULL), x, *x);
			for (i = 0; i < LOOPS; i++) {
				if (acquire_sem(the_lock) < 0) {
					printf("Failed to acquire the lock!\n");
					exit(-1);
				}
				*x = increment(*x);
				if (release_sem(the_lock) < 0) {
					printf("Failed to release the lock!\n");
					exit(-1);
				}
			}
			printf("child %8ld exiting: x = %p, *x = %d\n", 
			       find_thread(NULL), x, *x);
			exit(0);
		}
	}
	
	for (j = 0; j < KIDS; j++) {
		status_t ec = 0;
		wait_for_thread(pids[j], &ec);
	}
	printf("All children completed OK\n");
	if (*x != KIDS * LOOPS) {
		printf("Test FAILED!\n");
		printf("Should have seen *x = %d, instead got %d\n",
		       KIDS * LOOPS, *x);
	} else
		printf("Test passed!!!!\n");
}

int main(int argc, char **argv)
{
	char *addr = NULL;
	
	area_id aid = create_area("x", (void**)&addr, B_ANY_ADDRESS,
	                      B_PAGE_SIZE, B_LAZY_LOCK,
	                      B_READ_AREA | B_WRITE_AREA);
	if (aid < 0) {
		printf("Failed to create an area!\n");
		exit(-1);
	}
	x = (int *)addr;
	*x = 0;
	
	if ((the_lock = create_sem(1, "the_lock")) < 0) {
		printf("Failed to create the_lock :-(\n");
		exit(-1);
	}

	test_fork();
	
	delete_sem(the_lock);
	delete_area(aid);
	
	return 0;
}