/* 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/. */

/*
 *
 * Test atomic stack operations
 *
 *      Two stacks are created and threads add data items (each containing
 *      one of the first n integers) to the first stack, remove data items
 *      from the first stack and add them to the second stack. The primordial
 *      thread compares the sum of the first n integers to the sum of the
 *      integers in the data items in the second stack. The test succeeds if
 *      they are equal.
 */

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

typedef struct _DataRecord {
  PRInt32 data;
  PRStackElem link;
} DataRecord;

#define RECORD_LINK_PTR(lp) \
  ((DataRecord*)((char*)(lp) - offsetof(DataRecord, link)))

#define MAX_THREAD_CNT 100
#define DEFAULT_THREAD_CNT 4
#define DEFAULT_DATA_CNT 100
#define DEFAULT_LOOP_CNT 10000

/*
 * sum of the first n numbers using the formula n*(n+1)/2
 */
#define SUM_OF_NUMBERS(n) ((n & 1) ? (((n + 1) / 2) * n) : ((n / 2) * (n + 1)))

typedef struct stack_data {
  PRStack* list1;
  PRStack* list2;
  PRInt32 initial_data_value;
  PRInt32 data_cnt;
  PRInt32 loops;
} stack_data;

static void stackop(void* arg);

static int _debug_on;

PRFileDesc* output;
PRFileDesc* errhandle;

int main(int argc, char** argv) {
  PRInt32 rv, cnt, sum;
  DataRecord* Item;
  PRStack *list1, *list2;
  PRStackElem* node;
  PRStatus rc;

  PRInt32 thread_cnt = DEFAULT_THREAD_CNT;
  PRInt32 data_cnt = DEFAULT_DATA_CNT;
  PRInt32 loops = DEFAULT_LOOP_CNT;
  PRThread** threads;
  stack_data* thread_args;

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

  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': /* data count */
        data_cnt = atoi(opt->value);
        break;
      case 'l': /* loop count */
        loops = atoi(opt->value);
        break;
      default:
        break;
    }
  }
  PL_DestroyOptState(opt);

  PR_SetConcurrency(4);

  output = PR_GetSpecialFD(PR_StandardOutput);
  errhandle = PR_GetSpecialFD(PR_StandardError);
  list1 = PR_CreateStack("Stack_1");
  if (list1 == NULL) {
    PR_fprintf(errhandle, "PR_CreateStack failed - error %d\n", PR_GetError());
    return 1;
  }

  list2 = PR_CreateStack("Stack_2");
  if (list2 == NULL) {
    PR_fprintf(errhandle, "PR_CreateStack failed - error %d\n", PR_GetError());
    return 1;
  }

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

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

    thread_args[cnt].list1 = list1;
    thread_args[cnt].list2 = list2;
    thread_args[cnt].loops = loops;
    thread_args[cnt].data_cnt = data_cnt;
    thread_args[cnt].initial_data_value = 1 + cnt * data_cnt;

    if (cnt & 1) {
      scope = PR_GLOBAL_THREAD;
    } else {
      scope = PR_LOCAL_THREAD;
    }

    threads[cnt] =
        PR_CreateThread(PR_USER_THREAD, stackop, &thread_args[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 = 0x%x\n", argv[0], threads[cnt]);
  }

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

  node = PR_StackPop(list1);
  /*
   * list1 should be empty
   */
  if (node != NULL) {
    PR_fprintf(errhandle, "Error - Stack 1 not empty\n");
    PR_ASSERT(node == NULL);
    PR_ProcessExit(4);
  }

  cnt = data_cnt * thread_cnt;
  sum = 0;
  while (cnt-- > 0) {
    node = PR_StackPop(list2);
    /*
     * There should be at least 'cnt' number of records
     */
    if (node == NULL) {
      PR_fprintf(errhandle, "Error - PR_StackPop returned NULL\n");
      PR_ProcessExit(3);
    }
    Item = RECORD_LINK_PTR(node);
    sum += Item->data;
  }
  node = PR_StackPop(list2);
  /*
   * there should be exactly 'cnt' number of records
   */
  if (node != NULL) {
    PR_fprintf(errhandle, "Error - Stack 2 not empty\n");
    PR_ASSERT(node == NULL);
    PR_ProcessExit(4);
  }
  PR_DELETE(threads);
  PR_DELETE(thread_args);

  PR_DestroyStack(list1);
  PR_DestroyStack(list2);

  if (sum == SUM_OF_NUMBERS(data_cnt * thread_cnt)) {
    PR_fprintf(output, "%s successful\n", argv[0]);
    PR_fprintf(output, "\t\tsum = 0x%x, expected = 0x%x\n", sum,
               SUM_OF_NUMBERS(thread_cnt * data_cnt));
    return 0;
  } else {
    PR_fprintf(output, "%s failed: sum = 0x%x, expected = 0x%x\n", argv[0], sum,
               SUM_OF_NUMBERS(data_cnt * thread_cnt));
    return 2;
  }
}

static void stackop(void* thread_arg) {
  PRInt32 val, cnt, index, loops;
  DataRecord *Items, *Item;
  PRStack *list1, *list2;
  PRStackElem* node;
  stack_data* arg = (stack_data*)thread_arg;

  val = arg->initial_data_value;
  cnt = arg->data_cnt;
  loops = arg->loops;
  list1 = arg->list1;
  list2 = arg->list2;

  /*
   * allocate memory for the data records
   */
  Items = (DataRecord*)PR_CALLOC(sizeof(DataRecord) * cnt);
  PR_ASSERT(Items != NULL);
  index = 0;

  if (_debug_on)
    PR_fprintf(
        output,
        "Thread[0x%x] init_val = %d cnt = %d data1 = 0x%x datan = 0x%x\n",
        PR_GetCurrentThread(), val, cnt, &Items[0], &Items[cnt - 1]);

  /*
   * add the data records to list1
   */
  while (cnt-- > 0) {
    Items[index].data = val++;
    PR_StackPush(list1, &Items[index].link);
    index++;
  }

  /*
   * pop data records from list1 and add them back to list1
   * generates contention for the stack accesses
   */
  while (loops-- > 0) {
    cnt = arg->data_cnt;
    while (cnt-- > 0) {
      node = PR_StackPop(list1);
      if (node == NULL) {
        PR_fprintf(errhandle, "Error - PR_StackPop returned NULL\n");
        PR_ASSERT(node != NULL);
        PR_ProcessExit(3);
      }
      PR_StackPush(list1, node);
    }
  }
  /*
   * remove the data records from list1 and add them to list2
   */
  cnt = arg->data_cnt;
  while (cnt-- > 0) {
    node = PR_StackPop(list1);
    if (node == NULL) {
      PR_fprintf(errhandle, "Error - PR_StackPop returned NULL\n");
      PR_ASSERT(node != NULL);
      PR_ProcessExit(3);
    }
    PR_StackPush(list2, node);
  }
  if (_debug_on)
    PR_fprintf(output, "Thread[0x%x] init_val = %d cnt = %d exiting\n",
               PR_GetCurrentThread(), val, cnt);
}