/*-
 * 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 <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sysexits.h>
#include <string.h>
#include <time.h>
#include <err.h>

#include "stress.h"

static opt_t opt;
opt_t *op;

static char path[64];

static void
usage(const char *where)
{
        const char *help;

        if (where != NULL)
                printf("Error in \"%s\"\n", where);
        fprintf(stderr, "Usage: %s [-t | -l | -i | -d | -h | -k | -v]\n", getprogname());
        help =  " t <number><s|m|h|d> : time to run test\n"
                " l <pct>             : load factor 0 - 100%\n"
                " i <number>          : max # of parallel incarnations\n"
                " d <path>            : working directory\n"
                " h                   : hog resources\n"
                " k                   : terminate with SIGHUP + SIGKILL\n"
                " n                   : no startup delay\n"
                " v                   : verbose\n";
        printf("%s", help);
        exit(EX_USAGE);
}

static int
time2sec(const char *string)
{
        int r, s = 0;
        char modifier;
        r = sscanf(string, "%d%c", &s, &modifier);
        if (r == 2)
                switch(modifier) {
                case 's': break;
                case 'm': s = s * 60; break;
                case 'h': s = s * 60 * 60; break;
                case 'd': s = s * 60 * 60 * 24; break;
                default:
                        usage("-t");
                }
        else
                usage("-t");
        return (s);
}

static char *gete(const char *name)
{
        char *cp;
        char help[128];

        snprintf(help, sizeof(help), "%s%s", getprogname(), name);
        cp = getenv(help);
        if (cp == NULL)
                cp = getenv(name);
        return (cp);
}

static void
environment(void)
{
        char *cp;

        if ((cp = gete("INCARNATIONS")) != NULL) {
                if (sscanf(cp, "%d", &op->incarnations) != 1)
                        usage("INCARNATIONS");
        }
        if ((cp = gete("LOAD")) != NULL) {
                if (sscanf(cp, "%d", &op->load) != 1)
                        usage("LOAD");
        }
        if ((cp = gete("RUNTIME")) != NULL) {
                op->run_time = time2sec(cp);
        }
        if ((cp = gete("RUNDIR")) != NULL) {
                op->wd = cp;
        }
        if ((cp = gete("CTRLDIR")) != NULL) {
                op->cd = cp;
        }
        if ((cp = gete("HOG")) != NULL) {
                op->hog = 1;
        }
        if ((cp = gete("KILL")) != NULL) {
                op->kill = 1;
        }
        if ((cp = gete("NODELAY")) != NULL) {
                op->nodelay = 1;
        }
        if ((cp = gete("VERBOSE")) != NULL) {
                if (sscanf(cp, "%d", &op->verbose) != 1)
                        usage("VERBOSE");
        }
        if ((cp = gete("KBLOCKS")) != NULL) {
                if (sscanf(cp, "%jd", &op->kblocks) != 1)
                        usage("KBLOCKS");
        }
        if ((cp = gete("INODES")) != NULL) {
                if (sscanf(cp, "%jd", &op->inodes) != 1)
                        usage("INODES");
        }
}

void
options(int argc, char **argv)
{
        int ch;

        op = &opt;

        op->run_time    = 60;
        op->load        = 100;
        op->wd          = strdup("/tmp/stressX");
        op->cd          = strdup("/tmp/stressX.control");
        op->incarnations        = 1;
        op->hog         = 0;
        op->kill        = 0;
        op->nodelay     = 0;
        op->verbose     = 0;
        op->kblocks     = 0;
        op->inodes      = 0;

        environment();

        while ((ch = getopt(argc, argv, "t:l:i:d:hknv")) != -1)
                switch(ch) {
                case 't':       /* run time */
                        op->run_time = time2sec(optarg);
                        break;
                case 'l':       /* load factor in pct */
                        if (sscanf(optarg, "%d", &op->load) != 1)
                                usage("-l");
                        break;
                case 'i':       /* max incarnations */
                        if (sscanf(optarg, "%d", &op->incarnations) != 1)
                                usage("-i");
                        break;
                case 'd':       /* working directory */
                        op->wd = strdup(optarg);
                        break;
                case 'h':       /* hog flag */
                        op->hog += 1;
                        break;
                case 'k':       /* kill flag */
                        op->kill = 1;
                        break;
                case 'n':       /* no delay flag */
                        op->nodelay = 1;
                        break;
                case 'v':       /* verbose flag */
                        op->verbose += 1;
                        break;
                default:
                        usage(NULL);
                }
        op->argc = argc -= optind;
        op->argv = argv += optind;

        if (op->incarnations < 1)
                op->incarnations = 1;
        if (op->hog == 0)
                op->incarnations = random_int(1, op->incarnations);
        if (op->run_time < 15)
                op->run_time = 15;
        if (op->load < 0 || op->load > 100)
                op->load = 100;
}

void
show_status(void)
{
        char buf[80], pgname[9];
        int days;
        time_t t;

        if (op->verbose > 0) {
                strncpy(pgname, getprogname(), sizeof(pgname));
                pgname[8] = 0;
                t = op->run_time;
                days = t / (60 * 60 * 24);
                t = t % (60 * 60 * 24);
                strftime(buf, sizeof(buf), "%T", gmtime(&t));
                printf("%8s: run time %2d+%s, incarnations %3d, load %3d, "
                        "verbose %d\n",
                        pgname, days, buf, op->incarnations, op->load,
                        op->verbose);
                fflush(stdout);
        }
}

void
rmval(void)
{
        if (snprintf(path, sizeof(path), "%s/%s.conf", op->cd,
            getprogname()) < 0)
                err(1, "snprintf path");
        (void) unlink(path);
}

void
putval(unsigned long v)
{
        char buf[64];

        rmval();
        snprintf(buf, sizeof(buf), "%lu", v);
        if (symlink(buf, path) < 0)
                err(1, "symlink(%s, %s)", path, buf);
}

unsigned long
getval(void)
{
        int i, n;
        unsigned long val;
        char buf[64];

        if ((n = readlink(path, buf, sizeof(buf) -1)) < 0) {
                for (i = 0; i < 60; i++) {
                        sleep(1);
                        if ((n = readlink(path, buf, sizeof(buf) -1)) > 0)
                                break;
                }
                if (n < 0)
                        err(1, "readlink(%s). %s:%d", path, __FILE__,
                            __LINE__);
        }
        buf[n] = '\0';
        if (sscanf(buf, "%ld", &val) != 1)
                err(1, "sscanf(%s)", buf);
        return val;
}