/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
 * vim:expandtab:shiftwidth=8:tabstop=8:
 *
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 */

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <time.h>
#include <errno.h>
#include <string.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <getopt.h>

static void usage(char *prog)
{
        printf("usage: %s {-o|-m|-d|-l<tgt>} [-r altpath ] filenamefmt count\n", prog);
        printf("       %s {-o|-m|-d|-l<tgt>} [-r altpath ] filenamefmt ] -seconds\n", prog);
        printf("       %s {-o|-m|-d|-l<tgt>} [-r altpath ] filenamefmt start count\n", prog);
        exit(EXIT_FAILURE);
}

static char *get_file_name(const char *fmt, long n, int has_fmt_spec)
{
        static char filename[4096];
        int bytes;

        bytes = has_fmt_spec ? snprintf(filename, 4095, fmt, n) :
                snprintf(filename, 4095, "%s%ld", fmt, n);
        if (bytes >= 4095) {
                printf("file name too long\n");
                exit(EXIT_FAILURE);
        }
        return filename;
}

double now(void)
{
        struct timeval tv;
        gettimeofday(&tv, NULL);
        return (double)tv.tv_sec + (double)tv.tv_usec / 1000000;
}

int main(int argc, char ** argv)
{
        long i;
        int rc = 0, do_open = 0, do_link = 0, do_mkdir = 0;
        int do_unlink = 0, do_mknod = 0;
        char *filename;
        char *fmt = NULL, *fmt_unlink = NULL, *tgt = NULL;
        double start, last;
        long begin = 0, end = ~0UL >> 1, count = ~0UL >> 1;
        int c, has_fmt_spec = 0, unlink_has_fmt_spec = 0;

        /* Handle the last argument in form of "-seconds" */
        if (argc > 1 && argv[argc - 1][0] == '-') {
                char *endp;

                argc--;
                end = strtol(argv[argc] + 1, &endp, 0);
                if (end <= 0 || *endp != '\0')
                        usage(argv[0]);
                end = end + time(NULL);
        }

        while ((c = getopt(argc, argv, "omdl:r:")) != -1) {
                switch(c) {
                case 'o':
                        do_open++;
                        break;
                case 'm':
                        do_mknod++;
                        break;
                case 'd':
                        do_mkdir++;
                        break;
                case 'l':
                        do_link++;
                        tgt = optarg;
                        break;
                case 'r':
                        do_unlink++;
                        fmt_unlink = optarg;
                        break;
                case '?':
                        printf("Unknown option '%c'\n", optopt);
                        usage(argv[0]);
                }
        }

        if (do_open + do_mkdir + do_link + do_mknod != 1 ||
            do_unlink > 1)
                usage(argv[0]);

        switch (argc - optind) {
        case 3:
                begin = strtol(argv[argc - 2], NULL, 0);
        case 2:
                count = strtol(argv[argc - 1], NULL, 0);
                if (end != ~0UL >> 1)
                        usage(argv[0]);
        case 1:
                fmt = argv[optind];
                break;
        default:
                usage(argv[0]);
        }

        start = last = now();

        has_fmt_spec = strchr(fmt, '%') != NULL;
        if (do_unlink)
                unlink_has_fmt_spec = strchr(fmt_unlink, '%') != NULL;

        for (i = 0; i < count && time(NULL) < end; i++, begin++) {
                filename = get_file_name(fmt, begin, has_fmt_spec);
                if (do_open) {
                        int fd = open(filename, O_CREAT|O_RDWR, 0644);
                        if (fd < 0) {
                                printf("open(%s) error: %s\n", filename,
                                       strerror(errno));
                                rc = errno;
                                break;
                        }
                        close(fd);
                } else if (do_link) {
                        rc = link(tgt, filename);
                        if (rc) {
                                printf("link(%s, %s) error: %s\n",
                                       tgt, filename, strerror(errno));
                                rc = errno;
                                break;
                        }
                } else if (do_mkdir) {
                        rc = mkdir(filename, 0755);
                        if (rc) {
                                printf("mkdir(%s) error: %s\n",
                                       filename, strerror(errno));
                                rc = errno;
                                break;
                        }
                } else {
                        rc = mknod(filename, S_IFREG| 0444, 0);
                        if (rc) {
                                printf("mknod(%s) error: %s\n",
                                       filename, strerror(errno));
                                rc = errno;
                                break;
                        }
                }
                if (do_unlink) {
                        filename = get_file_name(fmt_unlink, begin,
                                      unlink_has_fmt_spec);
                        rc = do_mkdir ? rmdir(filename) : unlink(filename);
                        if (rc) {
                                printf("unlink(%s) error: %s\n",
                                       filename, strerror(errno));
                                rc = errno;
                                break;
                        }
                }

                if (i && (i % 10000) == 0) {
                        printf(" - created %ld (time %.2f total %.2f last %.2f)"
                               "\n", i, now(), now() - start, now() - last);
                        last = now();
                }
        }
        printf("total: %ld creates%s in %.2f seconds: %.2f creates/second\n", i,
               do_unlink ? "/deletions" : "",
               now() - start, ((double)i / (now() - start)));

        return rc;
}