open files

/*
 *
 *   Copyright (c) International Business Machines  Corp., 2001
 *
 *   This program is free software;  you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   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 for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program;  if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/*
 * FILE        : openfile.c
 * DESCRIPTION : Create files and open simultaneously
 * HISTORY:
 *   03/21/2001 Paul Larson (plars@us.ibm.com)
 *     -Ported
 *   11/01/2001 Mnaoj Iyer (manjo@austin.ibm.com)
 *     - Modified.
 *     added #inclide <unistd.h>
 *
 */

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>

#include "test.h"
#include "usctest.h"

char *TCID = "openfile01";    /* Test program identifier.    */
int TST_TOTAL = 1;

#define MAXFILES        32768
#define MAXTHREADS      10

/* Control Structure */
struct cb {
    pthread_mutex_t m;
    pthread_cond_t init_cv;
    pthread_cond_t thr_cv;
    int thr_sleeping;
} c;

/* Global Variables */
int numthreads = 10, numfiles = 10;
int debug = 0;
char *filename = "FILETOOPEN";

void setup(void)
{
    tst_tmpdir();
}

void cleanup(void)
{
    tst_rmdir();

}

/* Procedures */
void *threads(void *thread_id);

/* **************************************************************************
 *                              MAIN PROCEDURE                            *
 ************************************************************************** */

int main(int argc, char *argv[])
{
    int i, opt, badopts = 0;
    FILE *fd;
    pthread_t th_id;
    char msg[80] = "";
    extern char *optarg;

    while ((opt = getopt(argc, argv, "df:t:h")) != EOF) {
        switch ((char)opt) {
        case 'd':
            debug = 1;
            break;
        case 'f':
            numfiles = atoi(optarg);
            if (numfiles <= 0)
                badopts = 1;
            break;
        case 't':
            numthreads = atoi(optarg);
            if (numthreads <= 0)
                badopts = 1;
            break;
        case 'h':
        default:
            printf("Usage: openfile [-d] -f FILES -t THREADS
");
            _exit(1);
        }
    }
    if (badopts) {
        printf("Usage: openfile [-d] -f FILES -t THREADS
");
        _exit(1);
    }

    setup();

    /* Check if numthreads is less than MAXFILES */
    if (numfiles > MAXFILES) {
        sprintf(msg, "%s
Cannot use %d files", msg, numfiles);
        sprintf(msg, "%s, used %d files instead
", msg, MAXFILES);
        numfiles = MAXFILES;
    }

    /* Check if numthreads is less than MAXTHREADS */
    if (numthreads > MAXTHREADS) {
        sprintf(msg, "%s
Cannot use %d threads", msg, numthreads);
        sprintf(msg, "%s, used %d threads instead
", msg, MAXTHREADS);
        numthreads = MAXTHREADS;
    }

    /* Create files */
    if ((fd = fopen(filename, "w")) == NULL) {
        tst_resm(TFAIL, "Could not create file");
        cleanup();
    }

    /* Initialize thread control variables, lock & condition */
    pthread_mutex_init(&c.m, NULL);
    pthread_cond_init(&c.init_cv, NULL);
    pthread_cond_init(&c.thr_cv, NULL);
    c.thr_sleeping = 0;

    /* Grab mutex lock */
    if (pthread_mutex_lock(&c.m)) {
        tst_resm(TFAIL, "failed to grab mutex lock");
        fclose(fd);
        unlink(filename);
        cleanup();
    }

    printf("Creating Reading Threads
");

    /* Create threads */
    for (i = 0; i < numthreads; i++)
        if (pthread_create(&th_id, (pthread_attr_t *) NULL, threads,
                   (void *)(uintptr_t) i)) {
            tst_resm(TFAIL,
                 "failed creating a pthread; increase limits");
            fclose(fd);
            unlink(filename);
            cleanup();
        }

    /* Sleep until all threads are created */
    while (c.thr_sleeping != numthreads)
        if (pthread_cond_wait(&c.init_cv, &c.m)) {
            tst_resm(TFAIL,
                 "error while waiting for reading threads");
            fclose(fd);
            unlink(filename);
            cleanup();
        }

    /* Wake up all threads */
    if (pthread_cond_broadcast(&c.thr_cv)) {
        tst_resm(TFAIL, "failed trying to wake up reading threads");
        fclose(fd);
        unlink(filename);
        cleanup();
    }
    /* Release mutex lock */
    if (pthread_mutex_unlock(&c.m)) {
        tst_resm(TFAIL, "failed to release mutex lock");
        fclose(fd);
        unlink(filename);
        cleanup();
    }

    tst_resm(TPASS, "Threads are done reading");

    fclose(fd);
    unlink(filename);
    cleanup();
    _exit(0);
}

/* **************************************************************************
 *                OTHER PROCEDURES                *
 ************************************************************************** */

void close_files(FILE * fd_list[], int len)
{
    int i;
    for (i = 0; i < len; i++) {
        fclose(fd_list[i]);
    }
}

/* threads: Each thread opens the files specified */
void *threads(void *thread_id_)
{
    int thread_id = (uintptr_t) thread_id_;
    char errmsg[80];
    FILE *fd_list[MAXFILES];
    int i;

    /* Open files */
    for (i = 0; i < numfiles; i++) {
        if (debug)
            printf("Thread  %d : Opening file number %d 
",
                   thread_id, i);
        if ((fd_list[i] = fopen(filename, "rw")) == NULL) {
            sprintf(errmsg, "FAIL - Couldn't open file #%d", i);
            perror(errmsg);
            if (i > 0) {
                close_files(fd_list, i - 1);
            }
            unlink(filename);
            pthread_exit((void *)1);
        }
    }

    /* Grab mutex lock */
    if (pthread_mutex_lock(&c.m)) {
        perror("FAIL - failed to grab mutex lock");
        close_files(fd_list, numfiles);
        unlink(filename);
        pthread_exit((void *)1);
    }

    /* Check if you should wake up main thread */
    if (++c.thr_sleeping == numthreads)
        if (pthread_cond_signal(&c.init_cv)) {
            perror("FAIL - failed to signal main thread");
            close_files(fd_list, numfiles);
            unlink(filename);
            pthread_exit((void *)1);
        }

    /* Sleep until woken up */
    if (pthread_cond_wait(&c.thr_cv, &c.m)) {
        perror("FAIL - failed to wake up correctly");
        close_files(fd_list, numfiles);
        unlink(filename);
        pthread_exit((void *)1);
    }

    /* Release mutex lock */
    if (pthread_mutex_unlock(&c.m)) {
        perror("FAIL - failed to release mutex lock");
        close_files(fd_list, numfiles);
        unlink(filename);
        pthread_exit((void *)1);
    }

    /* Close file handles and exit */
    close_files(fd_list, numfiles);
    unlink(filename);
    pthread_exit((void *)0);
}