/*-
 * Copyright (c) 2008 Peter Holm <pho@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/param.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <err.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "stress.h"

static char path[MAXPATHLEN+1];
static int bufsize, freespace;

static void
reader(void) {
        fd_set set;
        struct timeval tv;
        int *buf, fd, n;

        setproctitle("reader");
        if ((fd = open(path, O_RDONLY | O_NONBLOCK)) < 0)
                err(1, "open(%s)", path);
        if ((buf = malloc(bufsize)) == NULL)
                        err(1, "malloc(%d), %s:%d", bufsize, __FILE__, __LINE__);
        n = 0;
        FD_ZERO(&set);
        FD_SET(fd, &set);
        tv.tv_sec = 10;
        tv.tv_usec = 0;
        if (select(fd + 1, &set, NULL, NULL, &tv) == 1) {
                if ((n = read(fd, buf, bufsize)) < 0)
                        err(1, "read(), %s:%d", __FILE__, __LINE__);
        }
        close(fd);
        free(buf);
}

static void
writer(void) {
        int *buf, fd;

        setproctitle("writer");
        if ((fd = open(path, O_WRONLY)) < 0) {
                unlink(path);
                err(1, "open(%s)", path);
        }
        if ((buf = malloc(bufsize)) == NULL)
                        err(1, "malloc(%d), %s:%d", bufsize, __FILE__, __LINE__);
        memset(buf, 0, bufsize);

        if (write(fd, buf, bufsize) < 0)
                err(1, "write(%d), %s:%d", fd, __FILE__, __LINE__);
        close(fd);
        free(buf);
}

int
setup(int nb)
{
        int64_t bl;
        int64_t in;
        int64_t reserve_bl;
        int64_t reserve_in;

        if (nb == 0) {
                getdf(&bl, &in);

                /* Resource requirements: */
                reserve_in =  200 * op->incarnations;
                reserve_bl = 2048 * op->incarnations;
                freespace = (reserve_bl <= bl && reserve_in <= in);
                if (!freespace)
                        reserve_bl = reserve_in = 0;

                if (op->verbose > 1)
                        printf("mkfifo(incarnations=%d). Free(%jdk, %jd), reserve(%jdk, %jd)\n",
                            op->incarnations, bl/1024, in, reserve_bl/1024, reserve_in);
                reservedf(reserve_bl, reserve_in);
                putval(freespace);
                fflush(stdout);
        } else {
                freespace = getval();
        }
        if (!freespace)
                _exit(0);
        bufsize = 2 << random_int(2, 12);

        return (0);
}

void
cleanup(void)
{
}

int
test(void)
{
        pid_t pid;
        int i, status;

        for (i = 0; i < 100; i++) {
                if (sprintf(path, "fifo.%d.%d", getpid(), i) < 0)
                        err(1, "sprintf()");
                if (mkfifo(path, 0600) < 0)
                        err(1, "mkfifo(%s)", path);
        }
        for (i = 0; i < 100; i++) {
                if (sprintf(path, "fifo.%d.%d", getpid(), i) < 0)
                        err(1, "sprintf()");
                if (unlink(path) < 0)
                        err(1, "unlink(%s)", path);
        }

        if (sprintf(path, "fifo.%d", getpid()) < 0)
                err(1, "sprintf()");
        if (mkfifo(path, 0600) < 0)
                err(1, "mkfifo(%s)", path);

        if ((pid = fork()) == 0) {
                writer();
                _exit(EXIT_SUCCESS);

        } else if (pid > 0) {
                reader();
                kill(pid, SIGINT);
                if (waitpid(pid, &status, 0) == -1)
                        warn("waitpid(%d)", pid);
        } else
                err(1, "fork(), %s:%d",  __FILE__, __LINE__);

        unlink(path);

        return (0);
}