/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
 *
 * RWLock tests
 *
 *  Several threads are created to access and modify data arrays using
 *  PRRWLocks for synchronization. Two data arrays, array_A and array_B, are
 *  initialized with random data and a third array, array_C, is initialized
 *  with the sum of the first 2 arrays.
 *
 *  Each one of the threads acquires a read lock to verify that the sum of
 *  the arrays A and B is equal to array C, and acquires a write lock to
 *  consistently update arrays A and B so that their is equal to array C.
 *
 */

#include "nspr.h"
#include "plgetopt.h"
#include "prrwlock.h"

static int _debug_on;
static void rwtest(void* args);
static PRInt32 *array_A, *array_B, *array_C;
static void update_array(void);
static void check_array(void);

typedef struct thread_args {
    PRRWLock* rwlock;
    PRInt32 loop_cnt;
} thread_args;

PRFileDesc* output;
PRFileDesc* errhandle;

#define DEFAULT_THREAD_CNT 4
#define DEFAULT_LOOP_CNT 100
#define TEST_ARRAY_SIZE 100

int
main(int argc, char** argv)
{
    PRInt32 cnt;
    PRStatus rc;
    PRInt32 i;

    PRInt32 thread_cnt = DEFAULT_THREAD_CNT;
    PRInt32 loop_cnt = DEFAULT_LOOP_CNT;
    PRThread** threads;
    thread_args* params;
    PRRWLock* rwlock1;

    PLOptStatus os;
    PLOptState* opt = PL_CreateOptState(argc, argv, "dt:c:");

    while (PL_OPT_EOL != (os = PL_GetNextOpt(opt))) {
        if (PL_OPT_BAD == os) {
            continue;
        }
        switch (opt->option) {
            case 'd': /* debug mode */
                _debug_on = 1;
                break;
            case 't': /* thread count */
                thread_cnt = atoi(opt->value);
                break;
            case 'c': /* loop count */
                loop_cnt = atoi(opt->value);
                break;
            default:
                break;
        }
    }
    PL_DestroyOptState(opt);

    PR_SetConcurrency(4);

    output = PR_GetSpecialFD(PR_StandardOutput);
    errhandle = PR_GetSpecialFD(PR_StandardError);

    rwlock1 = PR_NewRWLock(0, "Lock 1");
    if (rwlock1 == NULL) {
        PR_fprintf(errhandle, "PR_NewRWLock failed - error %d\n", PR_GetError());
        return 1;
    }

    threads = (PRThread**)PR_CALLOC(sizeof(PRThread*) * thread_cnt);
    params = (thread_args*)PR_CALLOC(sizeof(thread_args) * thread_cnt);

    /*
     * allocate and initialize data arrays
     */
    array_A = (PRInt32*)PR_MALLOC(sizeof(PRInt32) * TEST_ARRAY_SIZE);
    array_B = (PRInt32*)PR_MALLOC(sizeof(PRInt32) * TEST_ARRAY_SIZE);
    array_C = (PRInt32*)PR_MALLOC(sizeof(PRInt32) * TEST_ARRAY_SIZE);
    cnt = 0;
    for (i = 0; i < TEST_ARRAY_SIZE; i++) {
        array_A[i] = cnt++;
        array_B[i] = cnt++;
        array_C[i] = array_A[i] + array_B[i];
    }

    if (_debug_on)
        PR_fprintf(output, "%s: thread_cnt = %d loop_cnt = %d\n", argv[0],
                   thread_cnt, loop_cnt);
    for (cnt = 0; cnt < thread_cnt; cnt++) {
        PRThreadScope scope;

        params[cnt].rwlock = rwlock1;
        params[cnt].loop_cnt = loop_cnt;

        /*
         * create LOCAL and GLOBAL threads alternately
         */
        if (cnt & 1) {
            scope = PR_LOCAL_THREAD;
        } else {
            scope = PR_GLOBAL_THREAD;
        }

        threads[cnt] =
            PR_CreateThread(PR_USER_THREAD, rwtest, &params[cnt],
                            PR_PRIORITY_NORMAL, scope, PR_JOINABLE_THREAD, 0);
        if (threads[cnt] == NULL) {
            PR_fprintf(errhandle, "PR_CreateThread failed - error %d\n",
                       PR_GetError());
            PR_ProcessExit(2);
        }
        if (_debug_on)
            PR_fprintf(output, "%s: created thread = %p\n", argv[0], threads[cnt]);
    }

    for (cnt = 0; cnt < thread_cnt; cnt++) {
        rc = PR_JoinThread(threads[cnt]);
        PR_ASSERT(rc == PR_SUCCESS);
    }

    PR_DELETE(threads);
    PR_DELETE(params);

    PR_DELETE(array_A);
    PR_DELETE(array_B);
    PR_DELETE(array_C);

    PR_DestroyRWLock(rwlock1);

    printf("PASS\n");
    return 0;
}

static void
rwtest(void* args)
{
    PRInt32 index;
    thread_args* arg = (thread_args*)args;

    for (index = 0; index < arg->loop_cnt; index++) {
        /*
         * verify sum, update arrays and verify sum again
         */

        PR_RWLock_Rlock(arg->rwlock);
        check_array();
        PR_RWLock_Unlock(arg->rwlock);

        PR_RWLock_Wlock(arg->rwlock);
        update_array();
        PR_RWLock_Unlock(arg->rwlock);

        PR_RWLock_Rlock(arg->rwlock);
        check_array();
        PR_RWLock_Unlock(arg->rwlock);
    }
    if (_debug_on)
        PR_fprintf(output, "Thread[0x%x] lock = 0x%x exiting\n",
                   PR_GetCurrentThread(), arg->rwlock);
}

static void
check_array(void)
{
    PRInt32 i;

    for (i = 0; i < TEST_ARRAY_SIZE; i++)
        if (array_C[i] != (array_A[i] + array_B[i])) {
            PR_fprintf(output, "Error - data check failed\n");
            PR_ProcessExit(1);
        }
}

static void
update_array(void)
{
    PRInt32 i;

    for (i = 0; i < TEST_ARRAY_SIZE; i++) {
        array_A[i] += i;
        array_B[i] -= i;
    }
}