xref: /dragonfly/test/sysperf/pipe1.c (revision 636b1f09)

/*
 * pipe1.c
 *
 * $DragonFly: src/test/sysperf/pipe1.c,v 1.1 2003/08/12 02:29:44 dillon Exp $
 */

#include <sys/types.h>
#include <sys/wait.h>
#include "blib.h"

int
main(int ac, char **av)
{
    long long count = 0;
    long long max;
    char c[1];
    int j;
    int loops;
    int fds[2];

    printf("tests full duplex pipe 1write,2read,2write,1read loop\n");
    if (pipe(fds)) {
	perror("pipe");
	exit(1);
    }
    if (fork() == 0) {
	/*
	 * child process
	 */
	close(fds[0]);
	while (read(fds[1], c, sizeof(c)) == sizeof(c)) {
	    write(fds[1], c, sizeof(c));
	}
	_exit(0);
    } else {
	/*
	 * parent process.
	 */
	close(fds[1]);
	write(fds[0], c, sizeof(c));	/* prime the caches */
	read(fds[0], c, sizeof(c));

	start_timing();
	for (j = 0; ; ++j) {
	    write(fds[0], c, sizeof(c));
	    if (read(fds[0], c, sizeof(c)) != sizeof(c)) {
		fprintf(stderr, "broken pipe during test\n");
		exit(1);
	    }
	   if ((j & 31) == 0 && stop_timing(0, NULL))
		break;
	}
	loops = j;

	start_timing();
	for (j = 0; j < loops; ++j) {
	    write(fds[0], c, sizeof(c));
	    if (read(fds[0], c, sizeof(c)) != sizeof(c)) {
		fprintf(stderr, "broken pipe during test\n");
		exit(1);
	    }
	}
	stop_timing(j, "full duplex pipe / 1char:");
	close(fds[0]);
	while(wait(NULL) >= 0);
    }
    return(0);
}