宏HASH_INSERT

 

调用 方法 

HASH_INSERT(lock_t, hash, lock_sys->rec_hash,lock_rec_fold(space, page_no), lock);

/*******************************************************************//** Inserts a struct to a hash table. */

#define HASH_INSERT(TYPE, NAME, TABLE, FOLD, DATA)\
do {\ hash_cell_t* cell3333;\ //hash_cell_t* 定义 TYPE* struct3333;\ \ HASH_ASSERT_OWNED(TABLE, FOLD)\ \ (DATA)->NAME = NULL;\ \ cell3333 = hash_get_nth_cell(TABLE, hash_calc_hash(FOLD, TABLE));\ //函数定义 \ if (cell3333->node == NULL) {\ cell3333->node = DATA;\ } else {\ struct3333 = (TYPE*) cell3333->node;\ //此时struct3333的类型是lock_t \ while (struct3333->NAME != NULL) {\ //NAME 为 hash_node_t hash; typedef void* hash_node_t;

\ 　　　　　　struct3333 = (TYPE*) struct3333->NAME;\ 
　　　　}\ \ 
　　　　struct3333->NAME = DATA;\ 
}\ 
} while (0)

这里好绕

对于下一个元素, 都习惯于使用struct  结构体名称 *next

/**************************************************************//** Calculates the hash value from a folded value. @return hashed value */ UNIV_INLINE ulint hash_calc_hash( /*===========*/ ulint fold, /*!< in: folded value */ hash_table_t*    table)    /*!< in: hash table */ { ut_ad(table); ut_ad(table->magic_n == HASH_TABLE_MAGIC_N); return(ut_hash_ulint(fold, table->n_cells)); } ulint ut_hash_ulint( /*==========*/ ulint key, /*!< in: value to be hashed */ ulint table_size) /*!< in: hash table size */ { ut_ad(table_size); key = key ^ UT_HASH_RANDOM_MASK2; return(key % table_size); }

 

 

HASH_INSERT(lock_t, hash, lock_sys->rec_hash, lock_rec_fold(space, page_no), lock); /*********************************************************************//** Calculates the fold value of a page file address: used in inserting or searching for a lock in the hash table. @return folded value */ UNIV_INLINE ulint lock_rec_fold( /*==========*/ ulint space, /*!< in: space */ ulint page_no)/*!< in: page number */ { return(ut_fold_ulint_pair(space, page_no)); } /*************************************************************//** Folds a pair of ulints. @return folded value */ UNIV_INLINE ulint ut_fold_ulint_pair( /*===============*/ ulint n1, /*!< in: ulint */ ulint n2) /*!< in: ulint */ { return(((((n1 ^ n2 ^ UT_HASH_RANDOM_MASK2) << 8) + n1) ^ UT_HASH_RANDOM_MASK) + n2); }