table_cache-t.cc

/* Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.

   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,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

// First include (the generated) my_config.h, to get correct platform defines.
#include "my_config.h"
#include <gtest/gtest.h>
#include "test_utils.h"

#include "table_cache.h"

#include "ha_example.h"

/*
  We need example_hton to be able short-cut creation of example
  handler instances for mock TABLE objects.
*/
extern handlerton *example_hton;

namespace table_cache_unittest {

using my_testing::Server_initializer;


class TableCacheBasicTest : public ::testing::Test
{
protected:
  static const uint MAX_THREADS= 3;

  virtual void SetUp()
  {
    for (uint i= 0; i < MAX_THREADS; ++i)
    {
      initializer[i].SetUp();
      initializer[i].thd()->thread_id= i + 1;
    }

    ::testing::FLAGS_gtest_death_test_style = "threadsafe";
  }
  virtual void TearDown()
  {
    for (uint i= 0; i < MAX_THREADS; ++i)
      initializer[i].TearDown();
  }

  THD *get_thd(uint index) { return initializer[index].thd(); }

  Server_initializer initializer[MAX_THREADS];
};


class TableCacheSingleCacheTest : public TableCacheBasicTest
{
protected:
  virtual uint CachesNumber() { return 1; }
  virtual void SetUp()
  {
    TableCacheBasicTest::SetUp();

    /*
      In addition to table_cache_manager we want to have initialized
      TDC so we can use its HASH object for calculating hash values
      and be able to free TABLE objects correctly (we need LOCK_open
      initialized for this).
    */
    table_cache_instances= CachesNumber();
    table_cache_size_per_instance= 100;
    ASSERT_FALSE(table_def_init());
  }
  virtual void TearDown()
  {
    table_def_free();
    TableCacheBasicTest::TearDown();
  }
};


class TableCacheDoubleCacheTest : public TableCacheSingleCacheTest
{
protected:
  virtual uint CachesNumber() { return 2; }
};


class Mock_share : public TABLE_SHARE
{
  MEM_ROOT m_mem_root;
  Table_cache_element *cache_element_arr[Table_cache_manager::MAX_TABLE_CACHES];

public:
  Mock_share(const char *key)
  {
    memset((TABLE_SHARE *)this, 0, sizeof(TABLE_SHARE));
    /*
      Both table_cache_key and cache_element array are used by
      Table_cache code.
    */
    table_cache_key.str= (char*)key;
    table_cache_key.length= strlen(key);
    memset(cache_element_arr, 0, sizeof(cache_element_arr));
    cache_element= cache_element_arr;
    // MEM_ROOT is used for constructing ha_example() instances.
    init_alloc_root(&m_mem_root, 1024, 0);
    /*
      Assertion in some of Table_cache methods check that version of
      the share is up-to-date.
    */
    version= refresh_version;
    // Ensure that share is never destroyed.
    ref_count= UINT_MAX;
  }

  ~Mock_share()
  {
    free_root(&m_mem_root, MYF(0));
  }

  TABLE *create_table(THD *thd)
  {
    TABLE *result= (TABLE *)my_malloc(sizeof(TABLE), MYF(0));

    memset(result, 0, sizeof(TABLE));
    result->s= this;
    // We create TABLE which is already marked as used
    result->in_use= thd;
    /*
      Assertions in some of Table_cache methods need non-NULL
      TABLE::file and TABLE::db_stat. Code that frees unused
      TABLE objects needs proper "handler" instance.
    */
    result->file= new (&m_mem_root) ha_example(example_hton, this);
    result->db_stat= HA_READ_ONLY;

    return result;
  }

  void destroy_table(TABLE *table)
  {
    my_free(table);
  }
};

// Google Test recommends DeathTest suffix for classes used in death tests.
typedef TableCacheBasicTest TableCacheBasicDeathTest;
typedef TableCacheDoubleCacheTest TableCacheDoubleCacheDeathTest;

/*
  Test initilization/destruction of Table_cache.
*/

TEST_F(TableCacheBasicDeathTest, CacheCreateAndDestroy)
{
  Table_cache table_cache;

  ASSERT_FALSE(table_cache.init());

  // Cache should be empty after creation
  EXPECT_EQ(0U, table_cache.cached_tables());

  // Cache should be not locked after creation
#ifdef SAFE_MUTEX
  EXPECT_DEATH_IF_SUPPORTED(table_cache.assert_owner(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif
  table_cache.destroy();
}


/*
  Test locking for Table_cache object.
*/

TEST_F(TableCacheBasicDeathTest, CacheLockAndUnlock)
{
  Table_cache table_cache;

  ASSERT_FALSE(table_cache.init());

#ifdef SAFE_MUTEX
  // Cache should not be locked after creation
  EXPECT_DEATH_IF_SUPPORTED(table_cache.assert_owner(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif

  // And get locked after we call its lock() method
  table_cache.lock();
  table_cache.assert_owner();

  // And get unlocked after we call its unlock() method
  table_cache.unlock();
#ifdef SAFE_MUTEX
  EXPECT_DEATH_IF_SUPPORTED(table_cache.assert_owner(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif

  table_cache.destroy();
}


/*
  Tests for the rest of methods of Table_cache need to use an
  object controlled by the global instance of Table_cache_manager.
  Let us start testing of Table_cache_manager with test for
  its initialization/destruction. This test also covers well
  Table_cache_manager::get_cache() method.
*/

TEST_F(TableCacheBasicDeathTest, ManagerCreateAndDestroy)
{
  // Request two instances of Table_cache
  table_cache_instances= 2;

  ASSERT_FALSE(table_cache_manager.init());

  // All caches are empty after creation
  EXPECT_EQ(0U, table_cache_manager.cached_tables());

  // There should be two different caches in the manager
  Table_cache *cache_1, *cache_2, *cache_3;
  cache_1= table_cache_manager.get_cache(get_thd(0));
  cache_2= table_cache_manager.get_cache(get_thd(1));
  cache_3= table_cache_manager.get_cache(get_thd(2));
  EXPECT_TRUE(cache_1 != cache_2);
  // And not three !
  EXPECT_TRUE(cache_3 == cache_1);

  // Both caches should be empty
  EXPECT_EQ(0U, cache_1->cached_tables());
  EXPECT_EQ(0U, cache_2->cached_tables());

  // And not locked
#ifdef SAFE_MUTEX
  EXPECT_DEATH_IF_SUPPORTED(cache_1->assert_owner(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
  EXPECT_DEATH_IF_SUPPORTED(cache_2->assert_owner(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif

  table_cache_manager.destroy();
}


/*
  Test addition and removal of TABLE objects to/from the table cache.
*/

TEST_F(TableCacheSingleCacheTest, CacheAddAndRemove)
{
  THD *thd= get_thd(0);

  Mock_share share_1("share_1");
  TABLE *table_1= share_1.create_table(thd);

  Table_cache *table_cache= table_cache_manager.get_cache(thd);
  table_cache->lock();
  EXPECT_FALSE(table_cache->add_used_table(thd, table_1));

  // There should be one TABLE in the cache after we have added table_1.
  EXPECT_EQ(1U, table_cache->cached_tables());

  // There should be no unused TABLE objects for the same table in the
  // cache. OTOH it should contain info about table share of table_1.
  my_hash_value_type hash_value= my_calc_hash(&table_def_cache,
                                   (uchar*)share_1.table_cache_key.str,
                                   share_1.table_cache_key.length);
  TABLE *table_2;
  TABLE_SHARE *share_2;
  table_2= table_cache->get_table(thd, hash_value,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == NULL);
  EXPECT_TRUE(share_2 == &share_1);

  // Table_cache_iterator should be able to find only one TABLE instance
  // in all caches. And this instance should be table_1.
  Table_cache_iterator it(&share_1);
  EXPECT_TRUE(it++ == table_1);
  EXPECT_TRUE(it++ == NULL);

  // We must be able to release TABLE into table cache and reuse it after
  // this.
  table_cache->release_table(thd, table_1);
  table_2= table_cache->get_table(thd, hash_value,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == table_1);
  EXPECT_TRUE(share_2 == &share_1);

  table_cache->remove_table(table_1);

  // Once TABLE is removed from the cache the latter should become empty.
  EXPECT_EQ(0U, table_cache->cached_tables());

  table_2= table_cache->get_table(thd, hash_value,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == NULL);
  EXPECT_TRUE(share_2 == NULL);

  it.rewind();
  EXPECT_TRUE(it++ == NULL);

  // Also it should be possible to remove unused TABLE from the cache
  // Add TABLE instance and mark it as unused
  EXPECT_FALSE(table_cache->add_used_table(thd, table_1));
  table_cache->release_table(thd, table_1);

  table_cache->remove_table(table_1);

  // Once TABLE is removed from cache the latter should become empty.
  EXPECT_EQ(0U, table_cache->cached_tables());

  table_2= table_cache->get_table(thd, hash_value,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == NULL);
  EXPECT_TRUE(share_2 == NULL);

  table_cache->unlock();

  share_1.destroy_table(table_1);
}


/*
  Now let us test how Table_cache handles overflows.
*/

TEST_F(TableCacheSingleCacheTest, CacheOverflow)
{
  THD *thd= get_thd(0);

  // Set cache size low so it will overflow quickly.
  table_cache_size_per_instance= 2;

  Mock_share share_1("share_1");
  Mock_share share_2("share_2");
  TABLE *table_1= share_1.create_table(thd);
  TABLE *table_2= share_1.create_table(thd);
  TABLE *table_3= share_2.create_table(thd);

  Table_cache *table_cache= table_cache_manager.get_cache(thd);

  table_cache->lock();
  table_cache->add_used_table(thd, table_1);
  table_cache->add_used_table(thd, table_2);

  // There should be two TABLE instances in the cache.
  EXPECT_EQ(2U, table_cache->cached_tables());

  table_cache->release_table(thd, table_1);
  table_cache->release_table(thd, table_2);

  // Still there should be two TABLE instances in the cache.
  EXPECT_EQ(2U, table_cache->cached_tables());

  table_cache->add_used_table(thd, table_3);

  // One TABLE was added and one expelled (table_1), so still two TABLE objects.
  EXPECT_EQ(2U, table_cache->cached_tables());

  // Old value of table_1 points to garbage thanks to expelling
  table_1= share_1.create_table(thd);
  table_cache->add_used_table(thd, table_1);

  // Still two TABLE instances (table_2 was expelled).
  EXPECT_EQ(2U, table_cache->cached_tables());

  // Old value of table_2 points to garbage thanks to expelling
  table_2= share_1.create_table(thd);
  table_cache->add_used_table(thd, table_2);

  /*
    Now we should have three TABLE instances in cache since all
    of them are used.
  */
  EXPECT_EQ(3U, table_cache->cached_tables());

  table_cache->release_table(thd, table_2);

  // The first table that gets released is expelled.
  EXPECT_EQ(2U, table_cache->cached_tables());

  table_cache->remove_table(table_1);
  table_cache->remove_table(table_3);

  // Cache should be empty after that
  EXPECT_EQ(0U, table_cache->cached_tables());

  table_cache->unlock();

  share_1.destroy_table(table_1);
  share_1.destroy_table(table_3);
}


TEST_F(TableCacheSingleCacheTest, CacheGetAndRelease)
{
  THD *thd= get_thd(0);

  Table_cache *table_cache= table_cache_manager.get_cache(thd);

  table_cache->lock();

  TABLE *table_1, *table_2, *table_3;
  Mock_share share_1("share_1"), share_0("share_0");
  TABLE_SHARE *share_2;

  // There should be no TABLE in cache, nor information about share.
  my_hash_value_type hash_value_1= my_calc_hash(&table_def_cache,
                                     (uchar*)share_1.table_cache_key.str,
                                     share_1.table_cache_key.length);
  table_1= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_1 == NULL);
  EXPECT_TRUE(share_2 == NULL);

  table_1= share_1.create_table(thd);
  table_cache->add_used_table(thd, table_1);

  // There should be no unused TABLE in cache, but there should be
  // information about the share.
  table_2= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == NULL);
  EXPECT_TRUE(share_2 == &share_1);

  // There should be even no information about the share for which
  // TABLE was not added to cache.
  my_hash_value_type hash_value_0= my_calc_hash(&table_def_cache,
                                     (uchar*)share_0.table_cache_key.str,
                                     share_0.table_cache_key.length);
  table_2= table_cache->get_table(thd, hash_value_0,
                                  share_0.table_cache_key.str,
                                  share_0.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_2 == NULL);
  EXPECT_TRUE(share_2 == NULL);

  table_2= share_1.create_table(thd);
  table_cache->add_used_table(thd, table_2);

  // Still there should be no unused TABLE in cache, but there should
  // be information about the share.
  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 == NULL);
  EXPECT_TRUE(share_2 == &share_1);

  table_cache->release_table(thd, table_1);

  // After releasing one of TABLE objects it should be possible to get
  // unused TABLE from cache.
  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 == table_1);
  EXPECT_TRUE(share_2 == &share_1);

  // But only once!
  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 == NULL);
  EXPECT_TRUE(share_2 == &share_1);

  // After releasing of both TABLE objects it should be possible to
  // get two unused TABLE objects from cache (for 'share_1').
  // There should be nothing for 'share_0'.
  table_cache->release_table(thd, table_1);
  table_cache->release_table(thd, table_2);

  table_3= table_cache->get_table(thd, hash_value_0,
                                  share_0.table_cache_key.str,
                                  share_0.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 == NULL);
  EXPECT_TRUE(share_2 == NULL);


  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 != NULL);
  EXPECT_TRUE(share_2 == &share_1);
  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 != NULL);
  EXPECT_TRUE(share_2 == &share_1);
  table_3= table_cache->get_table(thd, hash_value_1,
                                  share_1.table_cache_key.str,
                                  share_1.table_cache_key.length,
                                  &share_2);
  EXPECT_TRUE(table_3 == NULL);
  EXPECT_TRUE(share_2 == &share_1);

  // Clean-up
  table_cache->remove_table(table_1);
  table_cache->remove_table(table_2);

  share_1.destroy_table(table_1);
  share_1.destroy_table(table_2);

  table_cache->unlock();
}


/*
  Test for Table_cache_manager/Table_cache::free_all_unused_tables().
*/

TEST_F(TableCacheDoubleCacheTest, ManagerFreeAllUnused)
{
  THD *thd_1= get_thd(0);
  THD *thd_2= get_thd(1);

  Table_cache *table_cache_1= table_cache_manager.get_cache(thd_1);
  Table_cache *table_cache_2= table_cache_manager.get_cache(thd_2);

  // There should be no TABLE instances in all cachea.
  EXPECT_EQ(0U, table_cache_manager.cached_tables());

  Mock_share share_1("share_1");
  Mock_share share_2("share_2");
  Mock_share share_3("share_2");
  TABLE *table_1= share_1.create_table(thd_1);
  TABLE *table_2= share_1.create_table(thd_1);
  TABLE *table_3= share_2.create_table(thd_1);
  TABLE *table_4= share_2.create_table(thd_1);
  TABLE *table_5= share_1.create_table(thd_2);
  TABLE *table_6= share_3.create_table(thd_2);

  table_cache_manager.lock_all_and_tdc();

  table_cache_1->add_used_table(thd_1, table_1);
  table_cache_1->add_used_table(thd_1, table_2);
  table_cache_1->add_used_table(thd_1, table_3);
  table_cache_1->add_used_table(thd_1, table_4);
  table_cache_2->add_used_table(thd_2, table_5);
  table_cache_2->add_used_table(thd_2, table_6);

  EXPECT_EQ(4U, table_cache_1->cached_tables());
  EXPECT_EQ(2U, table_cache_2->cached_tables());
  EXPECT_EQ(6U, table_cache_manager.cached_tables());

  table_cache_manager.free_all_unused_tables();

  // All TABLE instances should stay around in caches as
  // all of them are used.
  EXPECT_EQ(4U, table_cache_1->cached_tables());
  EXPECT_EQ(2U, table_cache_2->cached_tables());
  EXPECT_EQ(6U, table_cache_manager.cached_tables());

  table_cache_1->release_table(thd_1, table_1);

  table_cache_manager.free_all_unused_tables();

  // One table should be freed. So there should be 3 + 2 TABLE instances.
  EXPECT_EQ(3U, table_cache_1->cached_tables());
  EXPECT_EQ(2U, table_cache_2->cached_tables());
  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  table_cache_1->release_table(thd_1, table_2);
  table_cache_1->release_table(thd_1, table_3);
  table_cache_2->release_table(thd_2, table_5);

  table_cache_manager.free_all_unused_tables();

  // Now there should be 1 + 1 used TABLE instances left.
  EXPECT_EQ(1U, table_cache_1->cached_tables());
  EXPECT_EQ(1U, table_cache_2->cached_tables());
  EXPECT_EQ(2U, table_cache_manager.cached_tables());

  table_cache_1->release_table(thd_1, table_4);

  table_cache_manager.free_all_unused_tables();

  // There should be 0 + 1 TABLE instances around.
  EXPECT_EQ(0U, table_cache_1->cached_tables());
  EXPECT_EQ(1U, table_cache_2->cached_tables());
  EXPECT_EQ(1U, table_cache_manager.cached_tables());

  table_cache_2->release_table(thd_2, table_6);

  table_cache_manager.free_all_unused_tables();

  // All caches should become empty.
  EXPECT_EQ(0U, table_cache_1->cached_tables());
  EXPECT_EQ(0U, table_cache_2->cached_tables());
  EXPECT_EQ(0U, table_cache_manager.cached_tables());

  table_cache_manager.unlock_all_and_tdc();
}


/*
  Test for Table_cache_manager/Table_cache::cached_tables().
*/

TEST_F(TableCacheDoubleCacheTest, ManagerCachedTables)
{
  THD *thd_1= get_thd(0);
  THD *thd_2= get_thd(1);

  Table_cache *table_cache_1= table_cache_manager.get_cache(thd_1);
  Table_cache *table_cache_2= table_cache_manager.get_cache(thd_2);

  // There should be no TABLE instances in all cachea.
  EXPECT_EQ(0U, table_cache_1->cached_tables());
  EXPECT_EQ(0U, table_cache_2->cached_tables());
  EXPECT_EQ(0U, table_cache_manager.cached_tables());

  Mock_share share_1("share_1");
  Mock_share share_2("share_2");
  TABLE *table_1= share_1.create_table(thd_1);
  TABLE *table_2= share_1.create_table(thd_1);
  TABLE *table_3= share_2.create_table(thd_1);
  TABLE *table_4= share_1.create_table(thd_2);
  TABLE *table_5= share_2.create_table(thd_2);

  table_cache_manager.lock_all_and_tdc();

  table_cache_1->add_used_table(thd_1, table_1);
  table_cache_1->add_used_table(thd_1, table_2);
  table_cache_1->add_used_table(thd_1, table_3);

  // There should be 3 + 0 TABLE objects in cache
  EXPECT_EQ(3U, table_cache_1->cached_tables());
  EXPECT_EQ(0U, table_cache_2->cached_tables());
  EXPECT_EQ(3U, table_cache_manager.cached_tables());

  table_cache_2->add_used_table(thd_2, table_4);
  table_cache_2->add_used_table(thd_2, table_5);

  // There should be 3 + 2 TABLE objects in cache
  EXPECT_EQ(3U, table_cache_1->cached_tables());
  EXPECT_EQ(2U, table_cache_2->cached_tables());
  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  table_cache_1->release_table(thd_1, table_1);
  table_cache_2->release_table(thd_2, table_4);

  // There should be the same number of TABLE objects - 3 + 2
  EXPECT_EQ(3U, table_cache_1->cached_tables());
  EXPECT_EQ(2U, table_cache_2->cached_tables());
  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  table_cache_2->remove_table(table_5);

  // There should be 3 + 1 TABLE objects in cache
  EXPECT_EQ(3U, table_cache_1->cached_tables());
  EXPECT_EQ(1U, table_cache_2->cached_tables());
  EXPECT_EQ(4U, table_cache_manager.cached_tables());

  table_cache_1->remove_table(table_1);
  table_cache_2->remove_table(table_4);

  // There should be 2 + 0 TABLE objects in cache
  EXPECT_EQ(2U, table_cache_1->cached_tables());
  EXPECT_EQ(0U, table_cache_2->cached_tables());
  EXPECT_EQ(2U, table_cache_manager.cached_tables());

  table_cache_1->remove_table(table_2);
  table_cache_1->remove_table(table_3);

  // Caches should be empty
  EXPECT_EQ(0U, table_cache_1->cached_tables());
  EXPECT_EQ(0U, table_cache_2->cached_tables());
  EXPECT_EQ(0U, table_cache_manager.cached_tables());

  table_cache_manager.unlock_all_and_tdc();

  share_1.destroy_table(table_1);
  share_1.destroy_table(table_2);
  share_2.destroy_table(table_3);
  share_1.destroy_table(table_4);
  share_2.destroy_table(table_5);
}


/*
  Coverage for lock and unlock methods of Table_cache_manager class.
*/

TEST_F(TableCacheDoubleCacheDeathTest, ManagerLockAndUnlock)
{
  // Nor caches nor LOCK_open should not be locked after initialization
#ifdef SAFE_MUTEX
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.assert_owner_all(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.assert_owner_all_and_tdc(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif

  // And get locked after we call its lock_all_and_tdc() method.
  table_cache_manager.lock_all_and_tdc();
  table_cache_manager.assert_owner_all();
  table_cache_manager.assert_owner_all_and_tdc();

  // In addition to Table_cache_manager method we check this by
  // calling Table_cache methods and asserting state of LOCK_open.
  Table_cache *cache_1= table_cache_manager.get_cache(get_thd(0));
  Table_cache *cache_2= table_cache_manager.get_cache(get_thd(1));

  cache_1->assert_owner();
  cache_2->assert_owner();
  mysql_mutex_assert_owner(&LOCK_open);

  // Locks should be unlocked after we call unlock method
  table_cache_manager.unlock_all_and_tdc();

#ifdef SAFE_MUTEX
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.assert_owner_all(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.assert_owner_all_and_tdc(),
                            ".*Assertion.*count > 0.*pthread_equal.*");
#endif
}


/*
  Coverage for Table_cache_manager::free_table();
*/

TEST_F(TableCacheDoubleCacheDeathTest, ManagerFreeTable)
{
  THD *thd_1= get_thd(0);
  THD *thd_2= get_thd(1);

  Table_cache *table_cache_1= table_cache_manager.get_cache(thd_1);
  Table_cache *table_cache_2= table_cache_manager.get_cache(thd_2);

  Mock_share share_1("share_1");
  Mock_share share_2("share_2");
  TABLE *table_1= share_1.create_table(thd_1);
  TABLE *table_2= share_1.create_table(thd_1);
  TABLE *table_3= share_2.create_table(thd_1);
  TABLE *table_4= share_1.create_table(thd_2);
  TABLE *table_5= share_2.create_table(thd_2);

  table_cache_manager.lock_all_and_tdc();

  /*
    Coverage for TDC_RT_REMOVE_ALL case.
  */
  table_cache_1->add_used_table(thd_1, table_1);
  table_cache_1->add_used_table(thd_1, table_2);
  table_cache_1->release_table(thd_1, table_2);
  table_cache_1->add_used_table(thd_1, table_3);
  table_cache_2->add_used_table(thd_2, table_4);
  table_cache_2->add_used_table(thd_2, table_5);

  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  // There should be assert failure since we are trying
  // to free all tables for share_1, while some tables
  // are in use.
#ifndef DBUG_OFF
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.free_table(thd_1,
                                                           TDC_RT_REMOVE_ALL,
                                                           &share_1),
                            ".*Assertion.*is_empty.*");
#endif

  table_cache_1->release_table(thd_1, table_1);
  table_cache_2->release_table(thd_2, table_4);

  // After all tables for share_1 marked as unused freeing
  // all tables should succeed.
  table_cache_manager.free_table(thd_1, TDC_RT_REMOVE_ALL, &share_1);

  // We still should have 2 TABLE objects for share_2.
  EXPECT_EQ(2U, table_cache_manager.cached_tables());

  /*
    Coverage for TDC_RT_REMOVE_NOT_OWN case.
  */
  table_1= share_1.create_table(thd_1);
  table_2= share_1.create_table(thd_1);
  table_4= share_1.create_table(thd_2);

  table_cache_1->add_used_table(thd_1, table_1);
  table_cache_1->add_used_table(thd_1, table_2);
  table_cache_1->release_table(thd_1, table_2);
  table_cache_2->add_used_table(thd_2, table_4);

  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  // There should be assert failure since we are trying
  // to free all not own TABLEs for share_1, while thd_2
  // has a TABLE object for it in used
#ifndef DBUG_OFF
  EXPECT_DEATH_IF_SUPPORTED(table_cache_manager.free_table(thd_1,
                                                           TDC_RT_REMOVE_NOT_OWN,
                                                           &share_1),
                            ".*Assertion.*0.*");
#endif

  table_cache_2->release_table(thd_2, table_4);

  // After TABLE owned by thd_2 is marked as unused, the below
  // call should succeed.
  table_cache_manager.free_table(thd_1, TDC_RT_REMOVE_NOT_OWN, &share_1);

  // We still have 1 TABLE object for share_1 in thd_1 and
  // 2 TABLE objects for share_2.
  EXPECT_EQ(3U, table_cache_manager.cached_tables());

  /*
    Coverage for TDC_RT_REMOVE_UNUSED case.
  */
  table_2= share_1.create_table(thd_1);
  table_4= share_1.create_table(thd_2);

  table_cache_1->add_used_table(thd_1, table_2);
  table_cache_1->release_table(thd_1, table_2);
  table_cache_2->add_used_table(thd_2, table_4);

  EXPECT_EQ(5U, table_cache_manager.cached_tables());

  table_cache_manager.free_table(thd_1, TDC_RT_REMOVE_UNUSED, &share_1);

  // The above call should have been freed only 1 table.
  EXPECT_EQ(4U, table_cache_manager.cached_tables());

  // Mark all remaining TABLE objects for share_1 as unused
  table_cache_1->release_table(thd_1, table_1);
  table_cache_2->release_table(thd_2, table_4);

  table_cache_manager.free_table(thd_1, TDC_RT_REMOVE_UNUSED, &share_1);

  // The above call should free all unused TABLE objects for share_1.
  // Therefore only 2 objects for share_2 should be remaining
  EXPECT_EQ(2U, table_cache_manager.cached_tables());

  // Clean-up.
  table_cache_1->remove_table(table_3);
  table_cache_2->remove_table(table_5);

  share_2.destroy_table(table_3);
  share_2.destroy_table(table_5);

  table_cache_manager.unlock_all_and_tdc();
}


/*
  Coverage for Table_cache_iterator
*/

TEST_F(TableCacheDoubleCacheTest, Iterator)
{
  THD *thd_1= get_thd(0);
  THD *thd_2= get_thd(1);

  table_cache_manager.lock_all_and_tdc();

  Mock_share share_1("share_1");
  Mock_share share_2("share_2");

  // There is no TABLE objects for share_1 so the below iterator
  // should not find anything.
  Table_cache_iterator it(&share_1);
  EXPECT_TRUE(it++ == NULL);
  // Attempt to iterate behind the end should not give anything.
  EXPECT_TRUE(it++ == NULL);

  Table_cache *table_cache_1= table_cache_manager.get_cache(thd_1);
  Table_cache *table_cache_2= table_cache_manager.get_cache(thd_2);
  TABLE *table_1= share_1.create_table(thd_1);
  TABLE *table_2= share_1.create_table(thd_1);
  TABLE *table_3= share_2.create_table(thd_1);
  TABLE *table_4= share_1.create_table(thd_2);
  TABLE *table_5= share_2.create_table(thd_2);

  table_cache_2->add_used_table(thd_2, table_4);

  // Now the iterato should see table_4.
  it.rewind();
  TABLE *table_r1= it++;
  EXPECT_TRUE(table_r1 == table_4);
  // But only it.
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->add_used_table(thd_1, table_1);

  // Now we should see two tables:
  it.rewind();
  table_r1= it++;
  EXPECT_TRUE(table_r1 != NULL);
  TABLE *table_r2= it++;
  EXPECT_TRUE(table_r2 != NULL);
  EXPECT_TRUE(table_r1 != table_r2);
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->add_used_table(thd_1, table_2);

  // And now three !
  it.rewind();
  table_r1= it++;
  EXPECT_TRUE(table_r1 != NULL);
  table_r2= it++;
  EXPECT_TRUE(table_r2 != NULL);
  TABLE *table_r3= it++;
  EXPECT_TRUE(table_r3 != NULL);
  EXPECT_TRUE(table_r1 != table_r2 && table_r1 != table_r3 && table_r2 != table_r3);
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->release_table(thd_1, table_1);

  // We should be seeing only used TABLE objects, so two tables now
  it.rewind();
  table_r1= it++;
  EXPECT_TRUE(table_r1 != NULL);
  table_r2= it++;
  EXPECT_TRUE(table_r2 != NULL);
  EXPECT_TRUE(table_r1 != table_r2);
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->add_used_table(thd_1, table_3);
  table_cache_2->add_used_table(thd_2, table_5);

  // We also should not be seeing TABLE objects for share_2
  it.rewind();
  table_r1= it++;
  EXPECT_TRUE(table_r1 != NULL);
  table_r2= it++;
  EXPECT_TRUE(table_r2 != NULL);
  EXPECT_TRUE(table_r1 != table_r2);
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->remove_table(table_2);

  // Now we should se only one used TABLE
  it.rewind();
  table_r1= it++;
  EXPECT_TRUE(table_r1 == table_4);
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->remove_table(table_4);

  // And now no used TABLE objects for share_1 at all
  it.rewind();
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->remove_table(table_1);

  // Still the same
  it.rewind();
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_1->remove_table(table_3);
  table_cache_2->remove_table(table_5);

  // Cache is empty so iterator should not show any TABLE objects.
  it.rewind();
  EXPECT_TRUE(it++ == NULL);
  EXPECT_TRUE(it++ == NULL);

  table_cache_manager.unlock_all_and_tdc();

  share_1.destroy_table(table_1);
  share_1.destroy_table(table_2);
  share_2.destroy_table(table_3);
  share_1.destroy_table(table_4);
  share_2.destroy_table(table_5);
}

}