/*-
 * Copyright (C) 2005 IronPort Systems, Inc. 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.
 */

/* 
 * Prerequisities:
 * - AIO support must be compiled into the kernel (see sys/<arch>/NOTES for
 *   more details).
 *
 * Note: it is a good idea to run this against a physical drive to 
 * exercise the physio fast path (ie. aio_kqueue /dev/<something safe>)
 */

#include <sys/types.h>
#include <sys/event.h>
#include <sys/time.h>
#include <assert.h>
#include <aio.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>

#include "local.h"

#define PATH_TEMPLATE   "aio.XXXXXXXXXX"

#define MAX_RUNS 300
/* #define DEBUG */

int
main (int argc, char *argv[])
{
        struct aiocb **iocb, *kq_iocb;
        char *file, pathname[sizeof(PATH_TEMPLATE)+1];
        struct kevent kq_returned;
        struct timespec ts;
        char buffer[32768];
        int max_queue_per_proc;
        size_t max_queue_per_proc_size;
#ifdef DEBUG
        int cancel, error;
#endif
        int failed = 0, fd, kq, pending, result, run;
        int tmp_file = 0;
        int i, j;

        PLAIN_REQUIRE_UNSAFE_AIO(0);

        max_queue_per_proc_size = sizeof(max_queue_per_proc);
        if (sysctlbyname("vfs.aio.max_aio_queue_per_proc",
            &max_queue_per_proc, &max_queue_per_proc_size, NULL, 0) != 0)
                err(1, "sysctlbyname");
        iocb = calloc(max_queue_per_proc, sizeof(struct aiocb*));
        if (iocb == NULL)
                err(1, "calloc");

        kq = kqueue();
        if (kq < 0) {
                perror("No kqeueue\n");
                exit(1);
        }

        if (argc == 1) { 
                strcpy(pathname, PATH_TEMPLATE);
                fd = mkstemp(pathname);
                file = pathname;
                tmp_file = 1;
        } else {
                file = argv[1];
                fd = open(file, O_RDWR|O_CREAT, 0666);
        }
        if (fd == -1)
                err(1, "Can't open %s\n", file);

        for (run = 0; run < MAX_RUNS; run++){
#ifdef DEBUG
                printf("Run %d\n", run);
#endif
                for (i = 0; i < max_queue_per_proc; i++) {
                        iocb[i] = (struct aiocb *)calloc(1,
                            sizeof(struct aiocb));
                        if (iocb[i] == NULL)
                                err(1, "calloc");
                }

                pending = 0;
                for (i = 0; i < max_queue_per_proc; i++) {
                        pending++;
                        iocb[i]->aio_nbytes = sizeof(buffer);
                        iocb[i]->aio_buf = buffer;
                        iocb[i]->aio_fildes = fd;
                        iocb[i]->aio_offset = iocb[i]->aio_nbytes * i * run;

                        iocb[i]->aio_sigevent.sigev_notify_kqueue = kq;
                        iocb[i]->aio_sigevent.sigev_value.sival_ptr = iocb[i];
                        iocb[i]->aio_sigevent.sigev_notify = SIGEV_KEVENT;

                        result = aio_write(iocb[i]);
                        if (result != 0) {
                                perror("aio_write");
                                printf("Result %d iteration %d\n", result, i);
                                exit(1);
                        }
#ifdef DEBUG
                        printf("WRITE %d is at %p\n", i, iocb[i]);
#endif
                        result = rand();
                        if (result < RAND_MAX/32) {
                                if (result > RAND_MAX/64) {
                                        result = aio_cancel(fd, iocb[i]);
#ifdef DEBUG
                                        printf("Cancel %d %p result %d\n", i, iocb[i], result);
#endif
                                        if (result == AIO_CANCELED) {
                                                aio_return(iocb[i]);
                                                iocb[i] = NULL;
                                                pending--;
                                        }
                                }
                        }
                }
#ifdef DEBUG
                cancel = max_queue_per_proc - pending;
#endif

                i = 0;
                while (pending) {

                        for (;;) {

                                bzero(&kq_returned, sizeof(kq_returned));
                                ts.tv_sec = 0;
                                ts.tv_nsec = 1;
                                result = kevent(kq, NULL, 0,
                                                &kq_returned, 1, &ts);
#ifdef DEBUG
                                error = errno;
#endif
                                if (result < 0)
                                        perror("kevent error: ");
                                kq_iocb = kq_returned.udata;
#ifdef DEBUG
                                printf("kevent %d %d errno %d return.ident %p "
                                       "return.data %p return.udata %p %p"
                                       " filter %d flags %#x fflags %#x\n",
                                       i, result, error,
                                       (void*)kq_returned.ident,
                                       (void*)kq_returned.data,
                                       kq_returned.udata,
                                       kq_iocb,
                                       kq_returned.filter,
                                       kq_returned.flags,
                                       kq_returned.fflags);
                                if (result > 0)
                                        printf("\tsigev_notify_kevent_flags %#x\n",
                                       ((struct aiocb*)(kq_returned.ident))->aio_sigevent.sigev_notify_kevent_flags);
#endif

                                if (kq_iocb)
                                        break;
#ifdef DEBUG
                                printf("Try again left %d out of %d %d\n",
                                    pending, max_queue_per_proc, cancel);
#endif
                        }

                        for (j = 0; j < max_queue_per_proc && iocb[j] != kq_iocb;
                           j++) ;
                        assert(j < max_queue_per_proc);
#ifdef DEBUG
                        printf("kq_iocb %p\n", kq_iocb);

                        printf("Error Result for %d is %d pending %d\n",
                            j, result, pending);
#endif
                        result = aio_return(kq_iocb);
#ifdef DEBUG
                        printf("Return Result for %d is %d\n\n", j, result);
#endif
                        if (result != sizeof(buffer)) {
                                printf("FAIL: run %d, operation %d, result %d "
                                    " (errno=%d) should be %zu\n", run, pending,
                                    result, errno, sizeof(buffer));
                                failed++;
                        } else
                                printf("PASS: run %d, left %d\n", run,
                                    pending - 1);

                        free(kq_iocb);
                        iocb[j] = NULL;
                        pending--;
                        i++;
                }

                for (i = 0; i < max_queue_per_proc; i++)
                        free(iocb[i]);

        }

        if (tmp_file)
                unlink(pathname);

        if (failed != 0)
                printf("FAIL: %d tests failed\n", failed);
        else
                printf("PASS: All tests passed\n");

        exit (failed == 0 ? 0 : 1);
}