/* Copyright (C) 2006-2008 MySQL AB

   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; version 2 of the License.

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/*
  TODO: use pthread_join instead of wait_for_thread_count_to_be_zero, like in
  my_atomic-t.c (see BUG#22320).
*/

#include <tap.h>
#include <my_sys.h>
#include <m_string.h>
#include "test_file.h"
#include <tap.h>

#define PCACHE_SIZE (TEST_PAGE_SIZE*1024*8)

#ifndef DBUG_OFF
static const char* default_dbug_option;
#endif

static char *file1_name= (char*)"page_cache_test_file_1";
static PAGECACHE_FILE file1;
static pthread_cond_t COND_thread_count;
static pthread_mutex_t LOCK_thread_count;
static uint thread_count;
static PAGECACHE pagecache;

#ifdef TEST_HIGH_CONCURENCY
static uint number_of_readers= 10;
static uint number_of_writers= 20;
static uint number_of_tests= 30000;
static uint record_length_limit= TEST_PAGE_SIZE/200;
static uint number_of_pages= 20;
static uint flush_divider= 1000;
#else /*TEST_HIGH_CONCURENCY*/
#ifdef TEST_READERS
static uint number_of_readers= 10;
static uint number_of_writers= 1;
static uint number_of_tests= 30000;
static uint record_length_limit= TEST_PAGE_SIZE/200;
static uint number_of_pages= 20;
static uint flush_divider= 1000;
#undef SKIP_BIG_TESTS
#define SKIP_BIG_TESTS(X) /* no-op */
#else /*TEST_READERS*/
#ifdef TEST_WRITERS
static uint number_of_readers= 0;
static uint number_of_writers= 10;
static uint number_of_tests= 30000;
static uint record_length_limit= TEST_PAGE_SIZE/200;
static uint number_of_pages= 20;
static uint flush_divider= 1000;
#undef SKIP_BIG_TESTS
#define SKIP_BIG_TESTS(X) /* no-op */
#else /*TEST_WRITERS*/
static uint number_of_readers= 10;
static uint number_of_writers= 10;
static uint number_of_tests= 50000;
static uint record_length_limit= TEST_PAGE_SIZE/200;
static uint number_of_pages= 20000;
static uint flush_divider= 1000;
#endif /*TEST_WRITERS*/
#endif /*TEST_READERS*/
#endif /*TEST_HIGH_CONCURENCY*/


/**
  @brief Dummy pagecache callback.
*/

static my_bool
dummy_callback(uchar *page __attribute__((unused)),
               pgcache_page_no_t page_no __attribute__((unused)),
               uchar* data_ptr __attribute__((unused)))
{
  return 0;
}


/**
  @brief Dummy pagecache callback.
*/

static void
dummy_fail_callback(uchar* data_ptr __attribute__((unused)))
{
  return;
}


/*
  Get pseudo-random length of the field in (0;limit)

  SYNOPSYS
    get_len()
    limit                limit for generated value

  RETURN
    length where length >= 0 & length < limit
*/

static uint get_len(uint limit)
{
  return (uint)((ulonglong)rand()*(limit-1)/RAND_MAX);
}


/*
  Check page's consistency: layout is
  4 bytes: number 'num' of records in this page, then num occurences of
  { 4 bytes: record's length 'len'; then 4 bytes unchecked ('tag') then
  'len' bytes each equal to the record's sequential number in this page,
  modulo 256 }, then zeroes.
 */
uint check_page(uchar *buff, ulong offset, int page_locked, int page_no,
                int tag)
{
  uint end= sizeof(uint);
  uint num= uint4korr(buff);
  uint i;
  DBUG_ENTER("check_page");

  for (i= 0; i < num; i++)
  {
    uint len= uint4korr(buff + end);
    uint j;
    end+= 4 + 4;
    if (len + end > TEST_PAGE_SIZE)
    {
      diag("incorrect field header #%u by offset %lu\n", i, offset + end);
      goto err;
    }
    for(j= 0; j < len; j++)
    {
      if (buff[end + j] != (uchar)((i+1) % 256))
      {
        diag("incorrect %lu byte\n", offset + end + j);
        goto err;
      }
    }
    end+= len;
  }
  for(i= end; i < TEST_PAGE_SIZE; i++)
  {
    if (buff[i] != 0)
    {
      int h;
      DBUG_PRINT("err",
                 ("byte %lu (%lu + %u), page %u (%s, end: %u, recs: %u, tag: %d) should be 0\n",
                  offset + i, offset, i, page_no,
                  (page_locked ? "locked" : "unlocked"),
                  end, num, tag));
      diag("byte %lu (%lu + %u), page %u (%s, end: %u, recs: %u, tag: %d) should be 0\n",
           offset + i, offset, i, page_no,
           (page_locked ? "locked" : "unlocked"),
           end, num, tag);
      h= my_open("wrong_page", O_CREAT | O_TRUNC | O_RDWR, MYF(0));
      my_pwrite(h, (uchar*) buff, TEST_PAGE_SIZE, 0, MYF(0));
      my_close(h, MYF(0));
      goto err;
    }
  }
  DBUG_RETURN(end);
err:
  DBUG_PRINT("err", ("try to flush"));
  if (page_locked)
  {
    pagecache_delete(&pagecache, &file1, page_no,
                     PAGECACHE_LOCK_LEFT_WRITELOCKED, 1);
  }
  else
  {
    flush_pagecache_blocks(&pagecache, &file1, FLUSH_RELEASE);
  }
  exit(1);
}

void put_rec(uchar *buff, uint end, uint len, uint tag)
{
  uint i;
  uint num;
  num= uint4korr(buff);
  if (!len)
    len= 1;
  if (end + 4*2 + len > TEST_PAGE_SIZE)
    return;
  int4store(buff + end, len);
  end+=  4;
  int4store(buff + end, tag);
  end+=  4;
  num++;
  int4store(buff, num);
  for (i= end; i < (len + end); i++)
  {
    buff[i]= (uchar) num % 256;
  }
}

/*
  Recreate and reopen a file for test

  SYNOPSIS
    reset_file()
    file                 File to reset
    file_name            Path (and name) of file which should be reset
*/

void reset_file(PAGECACHE_FILE file, char *file_name)
{
  flush_pagecache_blocks(&pagecache, &file1, FLUSH_RELEASE);
  if (my_close(file1.file, MYF(0)) != 0)
  {
    diag("Got error during %s closing from close() (errno: %d)\n",
         file_name, errno);
    exit(1);
  }
  my_delete(file_name, MYF(0));
  if ((file.file= my_open(file_name,
                          O_CREAT | O_TRUNC | O_RDWR, MYF(0))) == -1)
  {
    diag("Got error during %s creation from open() (errno: %d)\n",
         file_name, errno);
    exit(1);
  }
}


void reader(int num)
{
  unsigned char *buffr= malloc(TEST_PAGE_SIZE);
  uint i;

  for (i= 0; i < number_of_tests; i++)
  {
    uint page= get_len(number_of_pages);
    pagecache_read(&pagecache, &file1, page, 3, buffr,
                   PAGECACHE_PLAIN_PAGE,
                   PAGECACHE_LOCK_LEFT_UNLOCKED,
                   0);
    check_page(buffr, page * TEST_PAGE_SIZE, 0, page, -num);

  }
  free(buffr);
}


void writer(int num)
{
  unsigned char *buffr= malloc(TEST_PAGE_SIZE);
  uint i;

  for (i= 0; i < number_of_tests; i++)
  {
    uint end;
    uint page= get_len(number_of_pages);
    pagecache_read(&pagecache, &file1, page, 3, buffr,
                   PAGECACHE_PLAIN_PAGE,
                   PAGECACHE_LOCK_WRITE,
                   0);
    end= check_page(buffr, page * TEST_PAGE_SIZE, 1, page, num);
    put_rec(buffr, end, get_len(record_length_limit), num);
    pagecache_write(&pagecache, &file1, page, 3, buffr,
                    PAGECACHE_PLAIN_PAGE,
                    PAGECACHE_LOCK_WRITE_UNLOCK,
                    PAGECACHE_UNPIN,
                    PAGECACHE_WRITE_DELAY,
                    0, LSN_IMPOSSIBLE);

    if (i % flush_divider == 0)
      flush_pagecache_blocks(&pagecache, &file1, FLUSH_FORCE_WRITE);
  }
  free(buffr);
}


static void *test_thread_reader(void *arg)
{
  int param=*((int*) arg);
  my_thread_init();
  {
    DBUG_ENTER("test_reader");
    DBUG_PRINT("enter", ("param: %d", param));

    reader(param);

    DBUG_PRINT("info", ("Thread %s ended", my_thread_name()));
    pthread_mutex_lock(&LOCK_thread_count);
    ok(1, "reader%d: done", param);
    thread_count--;
    VOID(pthread_cond_signal(&COND_thread_count)); /* Tell main we are ready */
    pthread_mutex_unlock(&LOCK_thread_count);
    free((uchar*) arg);
    my_thread_end();
  }
  return 0;
}


static void *test_thread_writer(void *arg)
{
  int param=*((int*) arg);
  my_thread_init();
  {
    DBUG_ENTER("test_writer");
    DBUG_PRINT("enter", ("param: %d", param));

    writer(param);

    DBUG_PRINT("info", ("Thread %s ended", my_thread_name()));
    pthread_mutex_lock(&LOCK_thread_count);
    ok(1, "writer%d: done", param);
    thread_count--;
    VOID(pthread_cond_signal(&COND_thread_count)); /* Tell main we are ready */
    pthread_mutex_unlock(&LOCK_thread_count);
    free((uchar*) arg);
    my_thread_end();
  }
  return 0;
}


int main(int argc __attribute__((unused)),
         char **argv __attribute__((unused)))
{
  pthread_t tid;
  pthread_attr_t thr_attr;
  int *param, error, pagen;

  MY_INIT(argv[0]);

#ifndef DBUG_OFF
#if defined(__WIN__)
  default_dbug_option= "d:t:i:O,\\test_pagecache_consist.trace";
#else
  default_dbug_option= "d:t:i:o,/tmp/test_pagecache_consist.trace";
#endif
  if (argc > 1)
  {
    DBUG_SET(default_dbug_option);
    DBUG_SET_INITIAL(default_dbug_option);
  }
#endif

  {
  DBUG_ENTER("main");
  DBUG_PRINT("info", ("Main thread: %s\n", my_thread_name()));
  plan(number_of_writers + number_of_readers);
  SKIP_BIG_TESTS(number_of_writers + number_of_readers)
  {

  if ((file1.file= my_open(file1_name,
                           O_CREAT | O_TRUNC | O_RDWR, MYF(0))) == -1)
  {
    diag( "Got error during file1 creation from open() (errno: %d)\n",
	    errno);
    exit(1);
  }
  pagecache_file_init(file1, &dummy_callback, &dummy_callback,
                      &dummy_fail_callback, &dummy_callback, NULL);
  DBUG_PRINT("info", ("file1: %d", file1.file));
  if (my_chmod(file1_name, S_IRWXU | S_IRWXG | S_IRWXO, MYF(MY_WME)))
    exit(1);
  my_pwrite(file1.file, (const uchar *)"test file", 9, 0, MYF(0));

  if ((error= pthread_cond_init(&COND_thread_count, NULL)))
  {
    diag( "COND_thread_count: %d from pthread_cond_init (errno: %d)\n",
	    error, errno);
    exit(1);
  }
  if ((error= pthread_mutex_init(&LOCK_thread_count, MY_MUTEX_INIT_FAST)))
  {
    diag( "LOCK_thread_count: %d from pthread_cond_init (errno: %d)\n",
	    error, errno);
    exit(1);
  }

  if ((error= pthread_attr_init(&thr_attr)))
  {
    diag("Got error: %d from pthread_attr_init (errno: %d)\n",
	    error,errno);
    exit(1);
  }
  if ((error= pthread_attr_setdetachstate(&thr_attr, PTHREAD_CREATE_DETACHED)))
  {
    diag(
	    "Got error: %d from pthread_attr_setdetachstate (errno: %d)\n",
	    error,errno);
    exit(1);
  }

#ifdef HAVE_THR_SETCONCURRENCY
  VOID(thr_setconcurrency(2));
#endif

  if ((pagen= init_pagecache(&pagecache, PCACHE_SIZE, 0, 0,
                             TEST_PAGE_SIZE, 0)) == 0)
  {
    diag("Got error: init_pagecache() (errno: %d)\n",
            errno);
    exit(1);
  }
  DBUG_PRINT("info", ("Page cache %d pages", pagen));
  {
    unsigned char *buffr= malloc(TEST_PAGE_SIZE);
    uint i;
    memset(buffr, '\0', TEST_PAGE_SIZE);
    for (i= 0; i < number_of_pages; i++)
    {
      pagecache_write(&pagecache, &file1, i, 3, buffr,
                      PAGECACHE_PLAIN_PAGE,
                      PAGECACHE_LOCK_LEFT_UNLOCKED,
                      PAGECACHE_PIN_LEFT_UNPINNED,
                      PAGECACHE_WRITE_DELAY,
                      0, LSN_IMPOSSIBLE);
    }
    flush_pagecache_blocks(&pagecache, &file1, FLUSH_FORCE_WRITE);
    free(buffr);
  }
  pthread_mutex_lock(&LOCK_thread_count);
  while (number_of_readers != 0 || number_of_writers != 0)
  {
    if (number_of_readers != 0)
    {
      param=(int*) malloc(sizeof(int));
      *param= number_of_readers;
      if ((error= pthread_create(&tid, &thr_attr, test_thread_reader,
                                 (void*) param)))
      {
        diag("Got error: %d from pthread_create (errno: %d)\n",
                error,errno);
        exit(1);
      }
      thread_count++;
      number_of_readers--;
    }
    if (number_of_writers != 0)
    {
      param=(int*) malloc(sizeof(int));
      *param= number_of_writers;
      if ((error= pthread_create(&tid, &thr_attr, test_thread_writer,
                                 (void*) param)))
      {
        diag("Got error: %d from pthread_create (errno: %d)\n",
                error,errno);
        exit(1);
      }
      thread_count++;
      number_of_writers--;
    }
  }
  DBUG_PRINT("info", ("Thread started"));
  pthread_mutex_unlock(&LOCK_thread_count);

  pthread_attr_destroy(&thr_attr);

  /* wait finishing */
  pthread_mutex_lock(&LOCK_thread_count);
  while (thread_count)
  {
    if ((error= pthread_cond_wait(&COND_thread_count,&LOCK_thread_count)))
      diag("COND_thread_count: %d from pthread_cond_wait\n",error);
  }
  pthread_mutex_unlock(&LOCK_thread_count);
  DBUG_PRINT("info", ("thread ended"));

  end_pagecache(&pagecache, 1);
  DBUG_PRINT("info", ("Page cache ended"));

  if (my_close(file1.file, MYF(0)) != 0)
  {
    diag( "Got error during file1 closing from close() (errno: %d)\n",
	    errno);
    exit(1);
  }
  my_delete(file1_name, MYF(0));

  DBUG_PRINT("info", ("file1 (%d) closed", file1.file));
  DBUG_PRINT("info", ("Program end"));

  } /* SKIP_BIG_TESTS */
  my_end(0);

  return exit_status();
  }
}
