/**********************************************************************
Data dictionary system

(c) 1996 Innobase Oy

Created 1/8/1996 Heikki Tuuri
***********************************************************************/

#include "dict0load.h"
#include "trx0undo.h"
#include "trx0sys.h"

/*************************************************************************
Gets the column data type. */
UNIV_INLINE
dtype_t*
dict_col_get_type(
/*==============*/
	dict_col_t*	col)
{
	ut_ad(col);

	return(&col->type);
}

/*************************************************************************
Gets the column number. */
UNIV_INLINE
ulint
dict_col_get_no(
/*============*/
	dict_col_t*	col)
{
	ut_ad(col);

	return(col->ind);
}

/*************************************************************************
Gets the column position in the clustered index. */
UNIV_INLINE
ulint
dict_col_get_clust_pos(
/*===================*/
	dict_col_t*	col)
{
	ut_ad(col);

	return(col->clust_pos);
}

/************************************************************************
Gets the first index on the table (the clustered index). */
UNIV_INLINE
dict_index_t*
dict_table_get_first_index(
/*=======================*/
				/* out: index, NULL if none exists */
	dict_table_t*	table)	/* in: table */
{
	ut_ad(table);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

	return(UT_LIST_GET_FIRST(table->indexes));
}

/************************************************************************
Gets the next index on the table. */
UNIV_INLINE
dict_index_t*
dict_table_get_next_index(
/*======================*/
				/* out: index, NULL if none left */
	dict_index_t*	index)	/* in: index */
{
	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);

	return(UT_LIST_GET_NEXT(indexes, index));
}

/************************************************************************
Gets the number of user-defined columns in a table in the dictionary
cache. */
UNIV_INLINE
ulint
dict_table_get_n_user_cols(
/*=======================*/
				/* out: number of user-defined (e.g., not
				ROW_ID) columns of a table */
	dict_table_t*	table)	/* in: table */
{
	ut_ad(table);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	ut_ad(table->cached);
	
	return(table->n_cols - DATA_N_SYS_COLS);
}

/************************************************************************
Gets the number of system columns in a table in the dictionary cache. */
UNIV_INLINE
ulint
dict_table_get_n_sys_cols(
/*======================*/
				/* out: number of system (e.g.,
				ROW_ID) columns of a table */
	dict_table_t*	table __attribute__((unused)))	/* in: table */
{
	ut_ad(table);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	ut_ad(table->cached);

	return(DATA_N_SYS_COLS);
}

/************************************************************************
Gets the number of all columns (also system) in a table in the dictionary
cache. */
UNIV_INLINE
ulint
dict_table_get_n_cols(
/*==================*/
				/* out: number of columns of a table */
	dict_table_t*	table)	/* in: table */
{
	ut_ad(table);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);
	ut_ad(table->cached);
	
	return(table->n_cols);
}

/************************************************************************
Gets the nth column of a table. */
UNIV_INLINE
dict_col_t*
dict_table_get_nth_col(
/*===================*/
				/* out: pointer to column object */
	dict_table_t*	table,	/* in: table */
	ulint		pos)	/* in: position of column */
{
	ut_ad(table);
	ut_ad(pos < table->n_def);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

	return((table->cols) + pos);
}

/************************************************************************
Gets the given system column of a table. */
UNIV_INLINE
dict_col_t*
dict_table_get_sys_col(
/*===================*/
				/* out: pointer to column object */
	dict_table_t*	table,	/* in: table */
	ulint		sys)	/* in: DATA_ROW_ID, ... */
{
	dict_col_t*	col;

	ut_ad(table);
	ut_ad(sys < DATA_N_SYS_COLS);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

	col = dict_table_get_nth_col(table, table->n_cols 
					   - DATA_N_SYS_COLS + sys);
	ut_ad(col->type.mtype == DATA_SYS);
	ut_ad(col->type.prtype == (sys | DATA_NOT_NULL));

	return(col);
}

/************************************************************************
Gets the given system column number of a table. */
UNIV_INLINE
ulint
dict_table_get_sys_col_no(
/*======================*/
				/* out: column number */
	dict_table_t*	table,	/* in: table */
	ulint		sys)	/* in: DATA_ROW_ID, ... */
{
	ut_ad(table);
	ut_ad(sys < DATA_N_SYS_COLS);
	ut_ad(table->magic_n == DICT_TABLE_MAGIC_N);

	return(table->n_cols - DATA_N_SYS_COLS + sys);
}

/************************************************************************
Gets the number of fields in the internal representation of an index,
including fields added by the dictionary system. */
UNIV_INLINE
ulint
dict_index_get_n_fields(
/*====================*/
				/* out: number of fields */
	dict_index_t*	index)	/* in: an internal representation of index
				(in the dictionary cache) */
{
	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
	
	return(index->n_fields);
}

/************************************************************************
Gets the number of fields in the internal representation of an index
that uniquely determine the position of an index entry in the index, if
we do not take multiversioning into account: in the B-tree use the value
returned by dict_index_get_n_unique_in_tree. */
UNIV_INLINE
ulint
dict_index_get_n_unique(
/*====================*/
				/* out: number of fields */
	dict_index_t*	index)	/* in: an internal representation of index
				(in the dictionary cache) */
{
	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
	ut_ad(index->cached);
	
	return(index->n_uniq);
}

/************************************************************************
Gets the number of fields in the internal representation of an index
which uniquely determine the position of an index entry in the index, if
we also take multiversioning into account. */
UNIV_INLINE
ulint
dict_index_get_n_unique_in_tree(
/*============================*/
				/* out: number of fields */
	dict_index_t*	index)	/* in: an internal representation of index
				(in the dictionary cache) */
{
	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
	ut_ad(index->cached);
	
	if (index->type & DICT_CLUSTERED) {

		return(dict_index_get_n_unique(index));
	}

	return(dict_index_get_n_fields(index));
}

/************************************************************************
Gets the number of user-defined ordering fields in the index. In the internal
representation of clustered indexes we add the row id to the ordering fields
to make a clustered index unique, but this function returns the number of
fields the user defined in the index as ordering fields. */
UNIV_INLINE
ulint
dict_index_get_n_ordering_defined_by_user(
/*======================================*/
				/* out: number of fields */
	dict_index_t*	index)	/* in: an internal representation of index
				(in the dictionary cache) */
{
	return(index->n_user_defined_cols);
}

/************************************************************************
Gets the nth field of an index. */
UNIV_INLINE
dict_field_t*
dict_index_get_nth_field(
/*=====================*/
				/* out: pointer to field object */
	dict_index_t*	index,	/* in: index */
	ulint		pos)	/* in: position of field */
{
	ut_ad(index);
	ut_ad(pos < index->n_def);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);

	return((index->fields) + pos);
}

/************************************************************************
Returns the position of a system column in an index. */
UNIV_INLINE
ulint
dict_index_get_sys_col_pos(
/*=======================*/
				/* out: position, ULINT_UNDEFINED if not
				contained */
	dict_index_t*	index,	/* in: index */
	ulint		type)	/* in: DATA_ROW_ID, ... */
{
	dict_col_t*	col;

	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
	ut_ad(!(index->type & DICT_UNIVERSAL));

	col = dict_table_get_sys_col(index->table, type);

	if (index->type & DICT_CLUSTERED) {

		return(col->clust_pos);
	}

	return(dict_index_get_nth_col_pos(index,
		dict_table_get_sys_col_no(index->table, type)));
}

/*************************************************************************
Gets the index tree where the index is stored. */
UNIV_INLINE
dict_tree_t*
dict_index_get_tree(
/*================*/
				/* out: index tree */
	dict_index_t*	index)	/* in: index */
{
	ut_ad(index);
	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);

	return(index->tree);
}	

/*************************************************************************
Gets the field order criterion. */
UNIV_INLINE
ulint
dict_field_get_order(
/*=================*/
	dict_field_t*	field)
{
	ut_ad(field);

	return(field->order);
}

/*************************************************************************
Gets the field column. */
UNIV_INLINE
dict_col_t*
dict_field_get_col(
/*===============*/
	dict_field_t*	field)
{
	ut_ad(field);

	return(field->col);
}

/************************************************************************
Gets pointer to the nth field data type in an index. */
UNIV_INLINE
dtype_t*
dict_index_get_nth_type(
/*====================*/
				/* out: data type */
	dict_index_t*	index,	/* in: index */
	ulint		pos)	/* in: position of the field */
{
	return(dict_col_get_type(dict_field_get_col(
			dict_index_get_nth_field(index, pos))));
}

/************************************************************************
Gets the column number the nth field in an index. */
UNIV_INLINE
ulint
dict_index_get_nth_col_no(
/*======================*/
				/* out: column number */
	dict_index_t*	index,	/* in: index */
	ulint		pos)	/* in: position of the field */
{
	return(dict_col_get_no(dict_field_get_col(
			dict_index_get_nth_field(index, pos))));
}

/*************************************************************************
Gets the space id of the root of the index tree. */
UNIV_INLINE
ulint
dict_tree_get_space(
/*================*/
				/* out: space id */
	dict_tree_t*	tree)	/* in: tree */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	return(tree->space);
}

/*************************************************************************
Sets the space id of the root of the index tree. */
UNIV_INLINE
void
dict_tree_set_space(
/*================*/
	dict_tree_t*	tree,	/* in: tree */
	ulint		space)	/* in: space id */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	tree->space = space;
}

/*************************************************************************
Gets the page number of the root of the index tree. */
UNIV_INLINE
ulint
dict_tree_get_page(
/*===============*/
				/* out: page number */
	dict_tree_t*	tree)	/* in: tree */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	return(tree->page);
}

/*************************************************************************
Sets the page number of the root of index tree. */
UNIV_INLINE
void
dict_tree_set_page(
/*===============*/
	dict_tree_t*	tree,	/* in: tree */
	ulint		page)	/* in: page number */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	tree->page = page;
}

/*************************************************************************
Gets the type of the index tree. */
UNIV_INLINE
ulint
dict_tree_get_type(
/*===============*/
				/* out: type */
	dict_tree_t*	tree)	/* in: tree */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	return(tree->type);
}

/*************************************************************************
Gets the read-write lock of the index tree. */
UNIV_INLINE
rw_lock_t*
dict_tree_get_lock(
/*===============*/
				/* out: read-write lock */
	dict_tree_t*	tree)	/* in: tree */
{
	ut_ad(tree);
	ut_ad(tree->magic_n == DICT_TREE_MAGIC_N);

	return(&(tree->lock));
}

/************************************************************************
Returns free space reserved for future updates of records. This is
relevant only in the case of many consecutive inserts, as updates
which make the records bigger might fragment the index. */
UNIV_INLINE
ulint
dict_tree_get_space_reserve(
/*========================*/
				/* out: number of free bytes on page,
				reserved for updates */
	dict_tree_t*	tree)	/* in: a tree */
{
	ut_ad(tree);

	UT_NOT_USED(tree);

	return(UNIV_PAGE_SIZE / 16);
}

/**************************************************************************
Checks if a table is in the dictionary cache. */
UNIV_INLINE
dict_table_t*
dict_table_check_if_in_cache_low(
/*==============================*/
					/* out: table, NULL if not found */
	const char*	table_name)	/* in: table name */
{
	dict_table_t*	table;
	ulint		table_fold;
	
	ut_ad(table_name);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	/* Look for the table name in the hash table */
	table_fold = ut_fold_string(table_name);

	HASH_SEARCH(name_hash, dict_sys->table_hash, table_fold, table,
				ut_strcmp(table->name, table_name) == 0);
	return(table);
}

/**************************************************************************
Gets a table; loads it to the dictionary cache if necessary. A low-level
function. */
UNIV_INLINE
dict_table_t*
dict_table_get_low(
/*===============*/
					/* out: table, NULL if not found */
	const char*	table_name)	/* in: table name */
{
	dict_table_t*	table;
	
	ut_ad(table_name);
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	table = dict_table_check_if_in_cache_low(table_name);
	
	if (table == NULL) {
		table = dict_load_table(table_name);
	}

	return(table);
}

/**************************************************************************
Returns a table object, based on table id, and memoryfixes it. */
UNIV_INLINE
dict_table_t*
dict_table_get_on_id_low(
/*=====================*/
				/* out: table, NULL if does not exist */
	dulint	table_id,	/* in: table id */
	trx_t*	trx)		/* in: transaction handle */
{
	dict_table_t*	table;
	ulint		fold;

#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */
	UT_NOT_USED(trx);
	
	/* Look for the table name in the hash table */
	fold = ut_fold_dulint(table_id);

	HASH_SEARCH(id_hash, dict_sys->table_id_hash, fold, table,
				ut_dulint_cmp(table->id, table_id) == 0);
	if (table == NULL) {
		table = dict_load_table_on_id(table_id);
	}

	if (table != NULL) {
		table->mem_fix++;

		/* lock_push(trx, table, LOCK_DICT_MEM_FIX) */
	}
	
	/* TODO: should get the type information from MySQL */
	
	return(table);
}

/**************************************************************************
Releases a table from being memoryfixed. Currently this has no relevance. */
UNIV_INLINE
void
dict_table_release(
/*===============*/
	dict_table_t*	table)	/* in: table to be released */
{
	mutex_enter(&(dict_sys->mutex));
	
	table->mem_fix--;	
	
	mutex_exit(&(dict_sys->mutex));
}

/**************************************************************************
Returns an index object. */
UNIV_INLINE
dict_index_t*
dict_table_get_index(
/*=================*/
				/* out: index, NULL if does not exist */
	dict_table_t*	table,	/* in: table */
	const char*	name)	/* in: index name */
{
	dict_index_t*	index	= NULL;
	
	index = dict_table_get_first_index(table);

	while (index != NULL) {
		if (ut_strcmp(name, index->name) == 0) {

			break;
		}

		index = dict_table_get_next_index(index);
	}	
	
	return(index);
}