Fix BUG#12071: "Windows hang: 'Opening tables' or 'Waiting for

 table' lockup".
 Changes from the innodb-4.1-ss11 snapshot.
 Do not call os_file-create_tmpfile() at runtime. Instead, create
 a tempfile at startup and guard access to it with a mutex.
 Also, fix bugs:
 10511: "Wrong padding of UCS2 CHAR columns in ON UPDATE CASCADE";
 13778: "If FOREIGN_KEY_CHECKS=0, one can create inconsistent FOREIGN
 KEYs". When FOREIGN_KEY_CHECKS=0 we still need to check that
 datatypes between foreign key references are compatible.
 Also, added test cases (also for bug 9802).

innobase/dict/dict0dict.c

@@ -2077,8 +2077,11 @@ dict_foreign_find_index(
 	dict_table_t*	table,	/* in: table */
 	const char**	columns,/* in: array of column names */
 	ulint		n_cols,	/* in: number of columns */
-	dict_index_t*	types_idx)/* in: NULL or an index to whose types the
-				column types must match */
+	dict_index_t*	types_idx, /* in: NULL or an index to whose types the
+				   column types must match */
+	ibool		check_charsets)	/* in: whether to check charsets.
+					only has an effect if types_idx !=
+					NULL. */
 {
 	dict_index_t*	index;
 	const char*	col_name;
@@ -2107,7 +2110,8 @@ dict_foreign_find_index(
 
 				if (types_idx && !cmp_types_are_equal(
 				     dict_index_get_nth_type(index, i),
-				     dict_index_get_nth_type(types_idx, i))) {
+				     dict_index_get_nth_type(types_idx, i),
+				     check_charsets)) {
 
 				  	break;
 				}		
@@ -2178,7 +2182,8 @@ dict_foreign_add_to_cache(
 /*======================*/
 					/* out: DB_SUCCESS or error code */
 	dict_foreign_t*	foreign,	/* in, own: foreign key constraint */
-	ibool		check_types)	/* in: TRUE=check type compatibility */
+	ibool		check_charsets)	/* in: TRUE=check charset
+					compatibility */
 {
 	dict_table_t*	for_table;
 	dict_table_t*	ref_table;
@@ -2214,16 +2219,10 @@ dict_foreign_add_to_cache(
 	}
 
 	if (for_in_cache->referenced_table == NULL && ref_table) {
-		dict_index_t*	types_idx;
-		if (check_types) {
-			types_idx = for_in_cache->foreign_index;
-		} else {
-			types_idx = NULL;
-		}
 		index = dict_foreign_find_index(ref_table,
 			(const char**) for_in_cache->referenced_col_names,
 			for_in_cache->n_fields,
-			types_idx);
+			for_in_cache->foreign_index, check_charsets);
 
 		if (index == NULL) {
 			dict_foreign_error_report(ef, for_in_cache,
@@ -2247,16 +2246,10 @@ dict_foreign_add_to_cache(
 	}
 
 	if (for_in_cache->foreign_table == NULL && for_table) {
-		dict_index_t*	types_idx;
-		if (check_types) {
-			types_idx = for_in_cache->referenced_index;
-		} else {
-			types_idx = NULL;
-		}
 		index = dict_foreign_find_index(for_table,
 			(const char**) for_in_cache->foreign_col_names,
 			for_in_cache->n_fields,
-			types_idx);
+			for_in_cache->referenced_index, check_charsets);
 
 		if (index == NULL) {
 			dict_foreign_error_report(ef, for_in_cache,
@@ -3033,7 +3026,7 @@ dict_create_foreign_constraints_low(
 	/* Try to find an index which contains the columns
 	as the first fields and in the right order */
 
-	index = dict_foreign_find_index(table, column_names, i, NULL);
+	index = dict_foreign_find_index(table, column_names, i, NULL, TRUE);
 
 	if (!index) {
 		mutex_enter(&dict_foreign_err_mutex);
@@ -3298,8 +3291,7 @@ dict_create_foreign_constraints_low(
 
 	if (referenced_table) {
 		index = dict_foreign_find_index(referenced_table,
-						column_names, i,
-						foreign->foreign_index);
+			column_names, i, foreign->foreign_index, TRUE);
 		if (!index) {
 			dict_foreign_free(foreign);
 			mutex_enter(&dict_foreign_err_mutex);

innobase/dict/dict0load.c

@@ -1094,7 +1094,7 @@ dict_load_foreign(
 				/* out: DB_SUCCESS or error code */
 	const char*	id,	/* in: foreign constraint id as a
 				null-terminated string */
-	ibool		check_types)/* in: TRUE=check type compatibility */
+	ibool		check_charsets)/* in: TRUE=check charset compatibility */
 {	
 	dict_foreign_t*	foreign;
 	dict_table_t*	sys_foreign;
@@ -1205,7 +1205,7 @@ dict_load_foreign(
 	a new foreign key constraint but loading one from the data
 	dictionary. */
 
-	return(dict_foreign_add_to_cache(foreign, check_types));
+	return(dict_foreign_add_to_cache(foreign, check_charsets));
 }
 
 /***************************************************************************
@@ -1220,7 +1220,8 @@ dict_load_foreigns(
 /*===============*/
 					/* out: DB_SUCCESS or error code */
 	const char*	table_name,	/* in: table name */
-	ibool		check_types)	/* in: TRUE=check type compatibility */
+	ibool		check_charsets)	/* in: TRUE=check charset
+					compatibility */
 {
 	btr_pcur_t	pcur;
 	mem_heap_t* 	heap;
@@ -1319,7 +1320,7 @@ dict_load_foreigns(
 
 	/* Load the foreign constraint definition to the dictionary cache */
 	
-	err = dict_load_foreign(id, check_types);
+	err = dict_load_foreign(id, check_charsets);
 
 	if (err != DB_SUCCESS) {
 		btr_pcur_close(&pcur);

innobase/include/dict0dict.h

@@ -197,7 +197,8 @@ dict_foreign_add_to_cache(
 /*======================*/
 					/* out: DB_SUCCESS or error code */
 	dict_foreign_t*	foreign,	/* in, own: foreign key constraint */
-	ibool		check_types);	/* in: TRUE=check type compatibility */
+	ibool		check_charsets);/* in: TRUE=check charset
+					compatibility */
 /*************************************************************************
 Checks if a table is referenced by foreign keys. */
 

innobase/include/dict0load.h

@@ -82,7 +82,8 @@ dict_load_foreigns(
 /*===============*/
 					/* out: DB_SUCCESS or error code */
 	const char*	table_name,	/* in: table name */
-	ibool		check_types);	/* in: TRUE=check type compatibility */
+	ibool		check_charsets);/* in: TRUE=check charsets
+					compatibility */
 /************************************************************************
 Prints to the standard output information on all tables found in the data
 dictionary system table. */

innobase/include/os0file.h

@@ -182,7 +182,7 @@ Creates a temporary file. */
 FILE*
 os_file_create_tmpfile(void);
 /*========================*/
-			/* out: temporary file handle (never NULL) */
+			/* out: temporary file handle, or NULL on error */
 /***************************************************************************
 The os_file_opendir() function opens a directory stream corresponding to the
 directory named by the dirname argument. The directory stream is positioned

innobase/include/rem0cmp.h

@@ -24,7 +24,8 @@ cmp_types_are_equal(
 				/* out: TRUE if the types are considered
 				equal in comparisons */
 	dtype_t*	type1,	/* in: type 1 */
-	dtype_t*	type2);	/* in: type 2 */
+	dtype_t*	type2,	/* in: type 2 */
+	ibool		check_charsets); /* in: whether to check charsets */
 /*****************************************************************
 This function is used to compare two data fields for which we know the
 data type. */

innobase/include/srv0srv.h

@@ -34,6 +34,12 @@ extern ibool	srv_lower_case_table_names;
 extern mutex_t	srv_monitor_file_mutex;
 /* Temporary file for innodb monitor output */
 extern FILE*	srv_monitor_file;
+/* Mutex for locking srv_dict_tmpfile.
+This mutex has a very high rank; threads reserving it should not
+be holding any InnoDB latches. */
+extern mutex_t	srv_dict_tmpfile_mutex;
+/* Temporary file for output from the data dictionary */
+extern FILE*	srv_dict_tmpfile;
 
 /* Server parameters which are read from the initfile */
 

innobase/rem/rem0cmp.c

@@ -98,7 +98,8 @@ cmp_types_are_equal(
 				/* out: TRUE if the types are considered
 				equal in comparisons */
 	dtype_t*	type1,	/* in: type 1 */
-	dtype_t*	type2)	/* in: type 2 */
+	dtype_t*	type2,	/* in: type 2 */
+	ibool		check_charsets) /* in: whether to check charsets */
 {
 	if (dtype_is_non_binary_string_type(type1->mtype, type1->prtype)
 	    && dtype_is_non_binary_string_type(type2->mtype, type2->prtype)) {
@@ -106,12 +107,12 @@ cmp_types_are_equal(
 		/* Both are non-binary string types: they can be compared if
 		and only if the charset-collation is the same */
 
-		if (dtype_get_charset_coll(type1->prtype)
-				== dtype_get_charset_coll(type2->prtype)) {
+		if (check_charsets) {
+			return(dtype_get_charset_coll(type1->prtype)
+			    == dtype_get_charset_coll(type2->prtype));
+		} else {
 			return(TRUE);
 		}
-
-		return(FALSE);
         }
 
 	if (dtype_is_binary_string_type(type1->mtype, type1->prtype)

innobase/row/row0ins.c

@@ -522,7 +522,7 @@ row_ins_cascade_calc_update_vec(
 				    && ufield->new_val.len
 				       < dtype_get_fixed_size(type)) {
 
-                                        ulint cset;
+					ulint	cset;
 
 				        ufield->new_val.data =
 						mem_heap_alloc(heap,
@@ -530,42 +530,42 @@ row_ins_cascade_calc_update_vec(
 					ufield->new_val.len = 
 						dtype_get_fixed_size(type);
 
-                                        /* Handle UCS2 strings differently.
-                                        As no new collations will be
-                                        introduced in 4.1, we hardcode the
-                                        charset-collation codes here.
-                                        In 5.0, the logic is based on
-                                        mbminlen. */
-                                        cset = dtype_get_charset_coll(
-                                          dtype_get_prtype(type));
-
-                                        if (cset == 35/*ucs2_general_ci*/
-                                            || cset == 90/*ucs2_bin*/
-                                            || (cset >= 128/*ucs2_unicode_ci*/
-                                          && cset <= 144
-                                          /*ucs2_persian_ci*/)) {
-                                          /* space=0x0020 */
-                                          ulint i;
-                                          for (i = 0;
-                                               i < ufield->new_val.len;
-                                               i += 2) {
-                                            mach_write_to_2(((byte*)
-                                              ufield->new_val.data)
-                                              + i, 0x0020);
-                                          }
-                                        } else {
-                                          ut_a(dtype_get_pad_char(type)
-                                              != ULINT_UNDEFINED);
-
-                                          memset(ufield->new_val.data,
-                                              (byte)dtype_get_pad_char(
-                                                type),
-                                              ufield->new_val.len);
-                                        }
-
-                                        memcpy(ufield->new_val.data,
-                                          parent_ufield->new_val.data,
-                                          parent_ufield->new_val.len);
+					/* Handle UCS2 strings differently.
+					As no new collations will be
+					introduced in 4.1, we hardcode the
+					charset-collation codes here.
+					In 5.0, the logic is based on
+					mbminlen. */
+					cset = dtype_get_charset_coll(
+						dtype_get_prtype(type));
+
+					if (cset == 35/*ucs2_general_ci*/
+					    || cset == 90/*ucs2_bin*/
+					    || (cset >= 128/*ucs2_unicode_ci*/
+						&& cset <= 144
+						/*ucs2_persian_ci*/)) {
+						/* space=0x0020 */
+						ulint	i;
+						for (i = 0;
+						     i < ufield->new_val.len;
+						     i += 2) {
+						    mach_write_to_2(((byte*)
+							ufield->new_val.data)
+							+ i, 0x0020);
+						}
+					} else {
+						ut_a(dtype_get_pad_char(type)
+						    != ULINT_UNDEFINED);
+
+						memset(ufield->new_val.data,
+						    (byte)dtype_get_pad_char(
+									type),
+						    ufield->new_val.len);
+					}
+
+					memcpy(ufield->new_val.data,
+						parent_ufield->new_val.data,
+						parent_ufield->new_val.len);
 				}
 
 				ufield->extern_storage = FALSE;

innobase/row/row0mysql.c

@@ -1804,7 +1804,7 @@ row_table_add_foreign_constraints(
 
 	if (err == DB_SUCCESS) {
 		/* Check that also referencing constraints are ok */
-		err = dict_load_foreigns(name, trx->check_foreigns);
+		err = dict_load_foreigns(name, TRUE);
 	}
 
 	if (err != DB_SUCCESS) {
@@ -2963,7 +2963,8 @@ row_rename_table_for_mysql(
 	mem_heap_t*	heap			= NULL;
 	const char**	constraints_to_drop	= NULL;
 	ulint		n_constraints_to_drop	= 0;
-        ibool           recovering_temp_table   = FALSE;
+	ibool           recovering_temp_table   = FALSE;
+	ibool		old_is_tmp, new_is_tmp;
 	ulint		len;
 	ulint		i;
         ibool		success;
@@ -3003,6 +3004,9 @@ row_rename_table_for_mysql(
 	trx->op_info = "renaming table";
 	trx_start_if_not_started(trx);
 
+	old_is_tmp = row_is_mysql_tmp_table_name(old_name);
+	new_is_tmp = row_is_mysql_tmp_table_name(new_name);
+	
 	if (row_mysql_is_recovered_tmp_table(new_name)) {
 
                 recovering_temp_table = TRUE;
@@ -3047,7 +3051,7 @@ row_rename_table_for_mysql(
 	len = (sizeof str1) + (sizeof str2) + (sizeof str3) + (sizeof str5) - 4
 		+ ut_strlenq(new_name, '\'') + ut_strlenq(old_name, '\'');
 
-	if (row_is_mysql_tmp_table_name(new_name)) {
+	if (new_is_tmp) {
 		db_name_len = dict_get_db_name_len(old_name) + 1;
 
 		/* MySQL is doing an ALTER TABLE command and it renames the
@@ -3200,7 +3204,7 @@ row_rename_table_for_mysql(
 		the table is stored in a single-table tablespace */
 
 		success = dict_table_rename_in_cache(table, new_name,
-				!row_is_mysql_tmp_table_name(new_name));
+				!new_is_tmp);
 		if (!success) {
 			trx->error_state = DB_SUCCESS;
 			trx_general_rollback_for_mysql(trx, FALSE, NULL);
@@ -3217,19 +3221,16 @@ row_rename_table_for_mysql(
 			goto funct_exit;
 		}
 
-		err = dict_load_foreigns(new_name, trx->check_foreigns);
-
-		if (row_is_mysql_tmp_table_name(old_name)) {
+		/* We only want to switch off some of the type checking in
+		an ALTER, not in a RENAME. */
+		
+		err = dict_load_foreigns(new_name,
+			old_is_tmp ? trx->check_foreigns : TRUE);
 
-			/* MySQL is doing an ALTER TABLE command and it
-			renames the created temporary table to the name
-			of the original table. In the ALTER TABLE we maybe
-			created some FOREIGN KEY constraints for the temporary
-			table. But we want to load also the foreign key
-			constraint definitions for the original table name. */
+		if (err != DB_SUCCESS) {
+			ut_print_timestamp(stderr);
 
-			if (err != DB_SUCCESS) {
-	    			ut_print_timestamp(stderr);
+			if (old_is_tmp) {
 				fputs("  InnoDB: Error: in ALTER TABLE ",
 					stderr);
 				ut_print_name(stderr, trx, new_name);
@@ -3237,36 +3238,23 @@ row_rename_table_for_mysql(
 	"InnoDB: has or is referenced in foreign key constraints\n"
 	"InnoDB: which are not compatible with the new table definition.\n",
 					stderr);
-
-				ut_a(dict_table_rename_in_cache(table,
-					old_name, FALSE));
-				trx->error_state = DB_SUCCESS;
-				trx_general_rollback_for_mysql(trx, FALSE,
-									NULL);
-				trx->error_state = DB_SUCCESS;
-			}
-		} else {
-			if (err != DB_SUCCESS) {
-
-	    			ut_print_timestamp(stderr);
-
+			} else {
 				fputs(
 				"  InnoDB: Error: in RENAME TABLE table ",
 					stderr);
 				ut_print_name(stderr, trx, new_name);
 				fputs("\n"
-     "InnoDB: is referenced in foreign key constraints\n"
-     "InnoDB: which are not compatible with the new table definition.\n",
+	"InnoDB: is referenced in foreign key constraints\n"
+	"InnoDB: which are not compatible with the new table definition.\n",
 					stderr);
-     
-				ut_a(dict_table_rename_in_cache(table,
-					old_name, FALSE));
-						
-				trx->error_state = DB_SUCCESS;
-				trx_general_rollback_for_mysql(trx, FALSE,
-									NULL);
-				trx->error_state = DB_SUCCESS;
 			}
+
+			ut_a(dict_table_rename_in_cache(table,
+					old_name, FALSE));
+			trx->error_state = DB_SUCCESS;
+			trx_general_rollback_for_mysql(trx, FALSE,
+				NULL);
+			trx->error_state = DB_SUCCESS;
 		}
 	}
 funct_exit:	

innobase/srv/srv0srv.c

@@ -334,6 +334,12 @@ mutex_t	srv_innodb_monitor_mutex;
 mutex_t	srv_monitor_file_mutex;
 /* Temporary file for innodb monitor output */
 FILE*	srv_monitor_file;
+/* Mutex for locking srv_dict_tmpfile.
+This mutex has a very high rank; threads reserving it should not
+be holding any InnoDB latches. */
+mutex_t	srv_dict_tmpfile_mutex;
+/* Temporary file for output from the data dictionary */
+FILE*	srv_dict_tmpfile;
 
 ulint	srv_main_thread_process_no	= 0;
 ulint	srv_main_thread_id		= 0;

innobase/srv/srv0start.c

@@ -1178,6 +1178,13 @@ NetWare. */
 		}
 	}
 
+	mutex_create(&srv_dict_tmpfile_mutex);
+	mutex_set_level(&srv_dict_tmpfile_mutex, SYNC_DICT_OPERATION);
+	srv_dict_tmpfile = os_file_create_tmpfile();
+	if (!srv_dict_tmpfile) {
+		return(DB_ERROR);
+	}
+
 	/* Restrict the maximum number of file i/o threads */
 	if (srv_n_file_io_threads > SRV_MAX_N_IO_THREADS) {
 
@@ -1804,8 +1811,13 @@ innobase_shutdown_for_mysql(void)
 			mem_free(srv_monitor_file_name);
 		}
 	}
-	
+	if (srv_dict_tmpfile) {
+		fclose(srv_dict_tmpfile);
+		srv_dict_tmpfile = 0;
+	}
+
 	mutex_free(&srv_monitor_file_mutex);
+	mutex_free(&srv_dict_tmpfile_mutex);
 
 	/* 3. Free all InnoDB's own mutexes and the os_fast_mutexes inside
 	them */

mysql-test/r/innodb.result

@@ -1722,3 +1722,35 @@ checksum table test_checksum;
 Table	Checksum
 test.test_checksum	2050879373
 drop table test_checksum;
+set foreign_key_checks=0;
+create table t2 (a int primary key, b int, foreign key (b) references t1(a)) engine = innodb;
+create table t1(a char(10) primary key, b varchar(20)) engine = innodb;
+ERROR HY000: Can't create table './test/t1.frm' (errno: 150)
+set foreign_key_checks=1;
+drop table t2;
+set foreign_key_checks=0;
+create table t1(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=latin1;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=utf8;
+ERROR HY000: Can't create table './test/t2.frm' (errno: 150)
+set foreign_key_checks=1;
+drop table t1;
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb;
+create table t1(a varchar(10) primary key) engine = innodb;
+alter table t1 modify column a int;
+Got one of the listed errors
+set foreign_key_checks=1;
+drop table t2,t1;
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=latin1;
+create table t1(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=latin1;
+alter table t1 convert to character set utf8;
+set foreign_key_checks=1;
+drop table t2,t1;
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=latin1;
+create table t3(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=utf8;
+rename table t3 to t1;
+ERROR HY000: Error on rename of './test/t3' to './test/t1' (errno: 150)
+set foreign_key_checks=1;
+drop table t2,t3;

mysql-test/t/innodb.test

@@ -1280,4 +1280,53 @@ connection a;
 checksum table test_checksum;
 drop table test_checksum;
 
+# tests for bugs #9802 and #13778
+
+# test that FKs between invalid types are not accepted
+
+set foreign_key_checks=0;
+create table t2 (a int primary key, b int, foreign key (b) references t1(a)) engine = innodb;
+-- error 1005
+create table t1(a char(10) primary key, b varchar(20)) engine = innodb;
+set foreign_key_checks=1;
+drop table t2;
+
+# test that FKs between different charsets are not accepted in CREATE even
+# when f_k_c is 0
+
+set foreign_key_checks=0;
+create table t1(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=latin1;
+-- error 1005
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=utf8;
+set foreign_key_checks=1;
+drop table t1;
+
+# test that invalid datatype conversions with ALTER are not allowed
+
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb;
+create table t1(a varchar(10) primary key) engine = innodb;
+-- error 1025,1025
+alter table t1 modify column a int;
+set foreign_key_checks=1;
+drop table t2,t1;
+
+# test that charset conversions with ALTER are allowed when f_k_c is 0
+
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=latin1;
+create table t1(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=latin1;
+alter table t1 convert to character set utf8;
+set foreign_key_checks=1;
+drop table t2,t1;
+
+# test that RENAME does not allow invalid charsets when f_k_c is 0
+
+set foreign_key_checks=0;
+create table t2 (a varchar(10), foreign key (a) references t1(a)) engine = innodb DEFAULT CHARSET=latin1;
+create table t3(a varchar(10) primary key) engine = innodb DEFAULT CHARSET=utf8;
+-- error 1025
+rename table t3 to t1;
+set foreign_key_checks=1;
+drop table t2,t3;
 # End of 4.1 tests

sql/ha_innodb.cc

@@ -4729,6 +4729,7 @@ ha_innobase::update_table_comment(
 	uint	length			= strlen(comment);
 	char*				str;
 	row_prebuilt_t*	prebuilt	= (row_prebuilt_t*)innobase_prebuilt;
+	long	flen;
 
 	/* We do not know if MySQL can call this function before calling
 	external_lock(). To be safe, update the thd of the current table
@@ -4748,43 +4749,43 @@ ha_innobase::update_table_comment(
 	trx_search_latch_release_if_reserved(prebuilt->trx);
 	str = NULL;
 
-	if (FILE* file = os_file_create_tmpfile()) {
-		long	flen;
+	/* output the data to a temporary file */
 
-		/* output the data to a temporary file */
-		fprintf(file, "InnoDB free: %lu kB",
+	mutex_enter_noninline(&srv_dict_tmpfile_mutex);
+	rewind(srv_dict_tmpfile);
+
+	fprintf(srv_dict_tmpfile, "InnoDB free: %lu kB",
       		   (ulong) fsp_get_available_space_in_free_extents(
       					prebuilt->table->space));
 
-		dict_print_info_on_foreign_keys(FALSE, file,
+	dict_print_info_on_foreign_keys(FALSE, srv_dict_tmpfile,
 				prebuilt->trx, prebuilt->table);
-		flen = ftell(file);
-		if (flen < 0) {
-			flen = 0;
-		} else if (length + flen + 3 > 64000) {
-			flen = 64000 - 3 - length;
-		}
+	flen = ftell(srv_dict_tmpfile);
+	if (flen < 0) {
+		flen = 0;
+	} else if (length + flen + 3 > 64000) {
+		flen = 64000 - 3 - length;
+	}
 
-		/* allocate buffer for the full string, and
-		read the contents of the temporary file */
+	/* allocate buffer for the full string, and
+	read the contents of the temporary file */
 
-		str = my_malloc(length + flen + 3, MYF(0));
+	str = my_malloc(length + flen + 3, MYF(0));
 
-		if (str) {
-			char* pos	= str + length;
-			if(length) {
-				memcpy(str, comment, length);
-				*pos++ = ';';
-				*pos++ = ' ';
-			}
-			rewind(file);
-			flen = fread(pos, 1, flen, file);
-			pos[flen] = 0;
+	if (str) {
+		char* pos	= str + length;
+		if (length) {
+			memcpy(str, comment, length);
+			*pos++ = ';';
+			*pos++ = ' ';
 		}
-
-		fclose(file);
+		rewind(srv_dict_tmpfile);
+		flen = (uint) fread(pos, 1, flen, srv_dict_tmpfile);
+		pos[flen] = 0;
 	}
 
+	mutex_exit_noninline(&srv_dict_tmpfile_mutex);
+
         prebuilt->trx->op_info = (char*)"";
 
   	return(str ? str : (char*) comment);
@@ -4802,6 +4803,7 @@ ha_innobase::get_foreign_key_create_info(void)
 {
 	row_prebuilt_t* prebuilt = (row_prebuilt_t*)innobase_prebuilt;
 	char*	str	= 0;
+	long	flen;
 
 	ut_a(prebuilt != NULL);
 
@@ -4811,47 +4813,42 @@ ha_innobase::get_foreign_key_create_info(void)
 
 	update_thd(current_thd);
 
-	if (FILE* file = os_file_create_tmpfile()) {
-		long	flen;
+	prebuilt->trx->op_info = (char*)"getting info on foreign keys";
 
-		prebuilt->trx->op_info = (char*)"getting info on foreign keys";
+	/* In case MySQL calls this in the middle of a SELECT query,
+	release possible adaptive hash latch to avoid
+	deadlocks of threads */
 
-		/* In case MySQL calls this in the middle of a SELECT query,
-		release possible adaptive hash latch to avoid
-		deadlocks of threads */
+	trx_search_latch_release_if_reserved(prebuilt->trx);
 
-		trx_search_latch_release_if_reserved(prebuilt->trx);
+	mutex_enter_noninline(&srv_dict_tmpfile_mutex);
+	rewind(srv_dict_tmpfile);
 
-		/* output the data to a temporary file */
-		dict_print_info_on_foreign_keys(TRUE, file,
+	/* output the data to a temporary file */
+	dict_print_info_on_foreign_keys(TRUE, srv_dict_tmpfile,
 				prebuilt->trx, prebuilt->table);
-		prebuilt->trx->op_info = (char*)"";
-
-		flen = ftell(file);
-		if (flen < 0) {
-			flen = 0;
-		} else if(flen > 64000 - 1) {
-			flen = 64000 - 1;
-		}
+	prebuilt->trx->op_info = (char*)"";
 
-		/* allocate buffer for the string, and
-		read the contents of the temporary file */
+	flen = ftell(srv_dict_tmpfile);
+	if (flen < 0) {
+		flen = 0;
+	} else if (flen > 64000 - 1) {
+		flen = 64000 - 1;
+	}
 
-		str = my_malloc(flen + 1, MYF(0));
+	/* allocate buffer for the string, and
+	read the contents of the temporary file */
 
-		if (str) {
-			rewind(file);
-			flen = fread(str, 1, flen, file);
-			str[flen] = 0;
-		}
+	str = my_malloc(flen + 1, MYF(0));
 
-		fclose(file);
-	} else {
-		/* unable to create temporary file */
-          	str = my_strdup(
-"/* Error: cannot display foreign key constraints */", MYF(0));
+	if (str) {
+		rewind(srv_dict_tmpfile);
+		flen = (uint) fread(str, 1, flen, srv_dict_tmpfile);
+		str[flen] = 0;
 	}
 
+	mutex_exit_noninline(&srv_dict_tmpfile_mutex);
+
   	return(str);
 }