dict0load.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

	btr_pcur_t	pcur;
	dtuple_t*	tuple;
	dfield_t*	dfield;
	ulint		pos_and_prefix_len;
	ulint		prefix_len;
	rec_t*		rec;
	byte*		field;
	ulint		len;
	byte*		buf;
	ulint		i;
	mtr_t		mtr;
	
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	UT_NOT_USED(table);

	mtr_start(&mtr);

	sys_fields = dict_table_get_low("SYS_FIELDS");
	sys_index = UT_LIST_GET_FIRST(sys_fields->indexes);
	ut_a(!sys_fields->comp);

	tuple = dtuple_create(heap, 1);
	dfield = dtuple_get_nth_field(tuple, 0);

	buf = mem_heap_alloc(heap, 8);
	mach_write_to_8(buf, index->id);

	dfield_set_data(dfield, buf, 8);
	dict_index_copy_types(tuple, sys_index, 1);

	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
						BTR_SEARCH_LEAF, &pcur, &mtr);
   	for (i = 0; i < index->n_fields; i++) {

		rec = btr_pcur_get_rec(&pcur);

		ut_a(btr_pcur_is_on_user_rec(&pcur, &mtr));
		if (rec_get_deleted_flag(rec, sys_fields->comp)) {
			dict_load_report_deleted_index(table->name, i);
		}
		
		field = rec_get_nth_field_old(rec, 0, &len);
		ut_ad(len == 8);
		ut_a(ut_memcmp(buf, field, len) == 0);

		field = rec_get_nth_field_old(rec, 1, &len);
		ut_a(len == 4);

		/* The next field stores the field position in the index
		and a possible column prefix length if the index field
		does not contain the whole column. The storage format is
		like this: if there is at least one prefix field in the index,
		then the HIGH 2 bytes contain the field number (== i) and the
		low 2 bytes the prefix length for the field. Otherwise the
		field number (== i) is contained in the 2 LOW bytes. */

		pos_and_prefix_len = mach_read_from_4(field);

		ut_a((pos_and_prefix_len & 0xFFFFUL) == i
		     || (pos_and_prefix_len & 0xFFFF0000UL) == (i << 16));

		if ((i == 0 && pos_and_prefix_len > 0)
		    || (pos_and_prefix_len & 0xFFFF0000UL) > 0) {

		        prefix_len = pos_and_prefix_len & 0xFFFFUL;
		} else {
		        prefix_len = 0;
		}

		ut_a(0 == ut_strcmp("COL_NAME",
			dict_field_get_col(
			dict_index_get_nth_field(sys_index, 4))->name));

		field = rec_get_nth_field_old(rec, 4, &len);

		dict_mem_index_add_field(index,
                                         mem_heap_strdupl(heap, (char*) field, len), 0, prefix_len);

		btr_pcur_move_to_next_user_rec(&pcur, &mtr);
	} 

	btr_pcur_close(&pcur);
	mtr_commit(&mtr);
}

/************************************************************************
Loads definitions for table indexes. Adds them to the data dictionary
cache. */
static
ibool
dict_load_indexes(
/*==============*/
				/* out: TRUE if ok, FALSE if corruption
				of dictionary table */
	dict_table_t*	table,	/* in: table */
	mem_heap_t*	heap)	/* in: memory heap for temporary storage */
{
	dict_table_t*	sys_indexes;
	dict_index_t*	sys_index;
	dict_index_t*	index;
	btr_pcur_t	pcur;
	dtuple_t*	tuple;
	dfield_t*	dfield;
	rec_t*		rec;
	byte*		field;
	ulint		len;
	ulint		name_len;
	char*		name_buf;
	ulint		type;
	ulint		space;
	ulint		page_no;
	ulint		n_fields;
	byte*		buf;
	ibool		is_sys_table;
	dulint		id;
	mtr_t		mtr;
	
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	if ((ut_dulint_get_high(table->id) == 0)
	    && (ut_dulint_get_low(table->id) < DICT_HDR_FIRST_ID)) {
		is_sys_table = TRUE;
	} else {
		is_sys_table = FALSE;
	}
	
	mtr_start(&mtr);

	sys_indexes = dict_table_get_low("SYS_INDEXES");
	sys_index = UT_LIST_GET_FIRST(sys_indexes->indexes);
	ut_a(!sys_indexes->comp);

	tuple = dtuple_create(heap, 1);
	dfield = dtuple_get_nth_field(tuple, 0);

	buf = mem_heap_alloc(heap, 8);
	mach_write_to_8(buf, table->id);

	dfield_set_data(dfield, buf, 8);
	dict_index_copy_types(tuple, sys_index, 1);

	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
						BTR_SEARCH_LEAF, &pcur, &mtr);
   	for (;;) {
		if (!btr_pcur_is_on_user_rec(&pcur, &mtr)) {

			break;
		}

		rec = btr_pcur_get_rec(&pcur);
		
		field = rec_get_nth_field_old(rec, 0, &len);
		ut_ad(len == 8);

		if (ut_memcmp(buf, field, len) != 0) {
			break;
		}

		if (rec_get_deleted_flag(rec, table->comp)) {
			dict_load_report_deleted_index(table->name,
				ULINT_UNDEFINED);

			btr_pcur_close(&pcur);
			mtr_commit(&mtr);

			return(FALSE);
		}

		field = rec_get_nth_field_old(rec, 1, &len);
		ut_ad(len == 8);
		id = mach_read_from_8(field);

		ut_a(0 == ut_strcmp("NAME",
			dict_field_get_col(
			dict_index_get_nth_field(sys_index, 4))->name));

		field = rec_get_nth_field_old(rec, 4, &name_len);
		name_buf = mem_heap_strdupl(heap, (char*) field, name_len);

		field = rec_get_nth_field_old(rec, 5, &len);
		n_fields = mach_read_from_4(field);

		field = rec_get_nth_field_old(rec, 6, &len);
		type = mach_read_from_4(field);

		field = rec_get_nth_field_old(rec, 7, &len);
		space = mach_read_from_4(field);

		ut_a(0 == ut_strcmp("PAGE_NO",
			dict_field_get_col(
			dict_index_get_nth_field(sys_index, 8))->name));

		field = rec_get_nth_field_old(rec, 8, &len);
		page_no = mach_read_from_4(field);

		if (page_no == FIL_NULL) {

			fprintf(stderr,
		"InnoDB: Error: trying to load index %s for table %s\n"
		"InnoDB: but the index tree has been freed!\n",
				name_buf, table->name);

			btr_pcur_close(&pcur);
			mtr_commit(&mtr);

			return(FALSE);
		}

		if ((type & DICT_CLUSTERED) == 0
			    && NULL == dict_table_get_first_index(table)) {

			fprintf(stderr,
		"InnoDB: Error: trying to load index %s for table %s\n"
		"InnoDB: but the first index is not clustered!\n",
				name_buf, table->name);

			btr_pcur_close(&pcur);
			mtr_commit(&mtr);

			return(FALSE);
		}
		
		if (is_sys_table
		    && ((type & DICT_CLUSTERED)
		        || ((table == dict_sys->sys_tables)
		            && (name_len == (sizeof "ID_IND") - 1)
			    && (0 == ut_memcmp(name_buf, "ID_IND",
							name_len))))) {

			/* The index was created in memory already at booting
			of the database server */
		} else {
 			index = dict_mem_index_create(table->name, name_buf,
						space, type, n_fields);
			index->id = id;
		
			dict_load_fields(table, index, heap);
			dict_index_add_to_cache(table, index, page_no);
		}

		btr_pcur_move_to_next_user_rec(&pcur, &mtr);
	} 

	btr_pcur_close(&pcur);
	mtr_commit(&mtr);

	return(TRUE);
}

/************************************************************************
Loads a table definition and also all its index definitions, and also
the cluster definition if the table is a member in a cluster. Also loads
all foreign key constraints where the foreign key is in the table or where
a foreign key references columns in this table. Adds all these to the data
dictionary cache. */

dict_table_t*
dict_load_table(
/*============*/
				/* out: table, NULL if does not exist;
				if the table is stored in an .ibd file,
				but the file does not exist,
				then we set the ibd_file_missing flag TRUE
				in the table object we return */
	const char*	name)	/* in: table name in the
				databasename/tablename format */
{
	ibool		ibd_file_missing	= FALSE;
	dict_table_t*	table;
	dict_table_t*	sys_tables;
	btr_pcur_t	pcur;
	dict_index_t*	sys_index;
	dtuple_t*	tuple;
	mem_heap_t*	heap;
	dfield_t*	dfield;
	rec_t*		rec;
	byte*		field;
	ulint		len;
	ulint		space;
	ulint		n_cols;
	ulint		err;
	mtr_t		mtr;
	
#ifdef UNIV_SYNC_DEBUG
	ut_ad(mutex_own(&(dict_sys->mutex)));
#endif /* UNIV_SYNC_DEBUG */

	heap = mem_heap_create(1000);
	
	mtr_start(&mtr);

	sys_tables = dict_table_get_low("SYS_TABLES");
	sys_index = UT_LIST_GET_FIRST(sys_tables->indexes);
	ut_a(!sys_tables->comp);

	tuple = dtuple_create(heap, 1);
	dfield = dtuple_get_nth_field(tuple, 0);

	dfield_set_data(dfield, name, ut_strlen(name));
	dict_index_copy_types(tuple, sys_index, 1);

	btr_pcur_open_on_user_rec(sys_index, tuple, PAGE_CUR_GE,
					BTR_SEARCH_LEAF, &pcur, &mtr);
	rec = btr_pcur_get_rec(&pcur);

	if (!btr_pcur_is_on_user_rec(&pcur, &mtr)
			|| rec_get_deleted_flag(rec, sys_tables->comp)) {
		/* Not found */

		btr_pcur_close(&pcur);
		mtr_commit(&mtr);
		mem_heap_free(heap);
		
		return(NULL);
	}	

	field = rec_get_nth_field_old(rec, 0, &len);

	/* Check if the table name in record is the searched one */
	if (len != ut_strlen(name) || ut_memcmp(name, field, len) != 0) {
		btr_pcur_close(&pcur);
		mtr_commit(&mtr);
		mem_heap_free(heap);
		
		return(NULL);
	}

	ut_a(0 == ut_strcmp("SPACE",
		dict_field_get_col(
		dict_index_get_nth_field(sys_index, 9))->name));
	
	field = rec_get_nth_field_old(rec, 9, &len);
	space = mach_read_from_4(field);

	/* Check if the tablespace exists and has the right name */
	if (space != 0) {
		if (fil_space_for_table_exists_in_mem(space, name, FALSE,
							FALSE, FALSE)) {
			/* Ok; (if we did a crash recovery then the tablespace
			can already be in the memory cache) */
		} else {
			/* In >= 4.1.9, InnoDB scans the data dictionary also
			at a normal mysqld startup. It is an error if the
			space object does not exist in memory. */

			ut_print_timestamp(stderr);
			fprintf(stderr,
"  InnoDB: error: space object of table %s,\n"
"InnoDB: space id %lu did not exist in memory. Retrying an open.\n",
							name, (ulong)space);
			/* Try to open the tablespace */
			if (!fil_open_single_table_tablespace(TRUE,
							space, name)) {
				/* We failed to find a sensible tablespace
				file */

				ibd_file_missing = TRUE;
			}
		}
	}

	ut_a(0 == ut_strcmp("N_COLS",
		dict_field_get_col(
		dict_index_get_nth_field(sys_index, 4))->name));

	field = rec_get_nth_field_old(rec, 4, &len);
	n_cols = mach_read_from_4(field);

	/* The high-order bit of N_COLS is the "compact format" flag. */
	table = dict_mem_table_create(name, space,
					n_cols & ~0x80000000UL,
					!!(n_cols & 0x80000000UL));

	table->ibd_file_missing = ibd_file_missing;

	ut_a(0 == ut_strcmp("ID",
		dict_field_get_col(
		dict_index_get_nth_field(sys_index, 3))->name));

	field = rec_get_nth_field_old(rec, 3, &len);
	table->id = mach_read_from_8(field);

	field = rec_get_nth_field_old(rec, 5, &len);
	table->type = mach_read_from_4(field);

	if (table->type == DICT_TABLE_CLUSTER_MEMBER) {
		ut_error;
#if 0 /* clustered tables have not been implemented yet */
		field = rec_get_nth_field_old(rec, 6, &len);
		table->mix_id = mach_read_from_8(field);

		field = rec_get_nth_field_old(rec, 8, &len);
		table->cluster_name = mem_heap_strdupl(heap, (char*) field, len);
#endif
	}

	if ((table->type == DICT_TABLE_CLUSTER)
	    || (table->type == DICT_TABLE_CLUSTER_MEMBER)) {

		field = rec_get_nth_field_old(rec, 7, &len);
		ut_a(len == 4);
		table->mix_len = mach_read_from_4(field);
	}

	btr_pcur_close(&pcur);
	mtr_commit(&mtr);

	if (table->type == DICT_TABLE_CLUSTER_MEMBER) {
		/* Load the cluster table definition if not yet in
		memory cache */
		dict_table_get_low(table->cluster_name);
	}

	dict_load_columns(table, heap);

	dict_table_add_to_cache(table);
	
	dict_load_indexes(table, heap);
	
	err = dict_load_foreigns(table->name, TRUE);
/*
	if (err != DB_SUCCESS) {
	
 		mutex_enter(&dict_foreign_err_mutex);

 		ut_print_timestamp(stderr);
 		
		fprintf(stderr,
"  InnoDB: Error: could not make a foreign key definition to match\n"
"InnoDB: the foreign key table or the referenced table!\n"
"InnoDB: The data dictionary of InnoDB is corrupt. You may need to drop\n"
"InnoDB: and recreate the foreign key table or the referenced table.\n"
"InnoDB: Submit a detailed bug report to http://bugs.mysql.com\n"
"InnoDB: Latest foreign key error printout:\n%s\n", dict_foreign_err_buf);
				
		mutex_exit(&dict_foreign_err_mutex);
	}
*/
	mem_heap_free(heap);

	return(table);
}

/***************************************************************************
Loads a table object based on the table id. */

dict_table_t*
dict_load_table_on_id(
/*==================*/
				/* out: table; NULL if table does not exist */
	dulint	table_id)	/* in: table id */