branches/zip: Make innodb_file_per_table a settable global variable.

There is one consideration: fil_init() chooses the tablespace hash size
based on the initial value of srv_file_per_table.  However, this is nothing
new: InnoDB could be started with innodb_file_per_table=0 even though
*.ibd files exist.

srv_file_per_table: Declare as my_bool instead of ibool, because
MYSQL_SYSVAR_BOOL() expects a pointer to my_bool.  Document the
variable also in srv0srv.h.

innobase_start_or_create_for_mysql(): Note why it is OK to temporarily
clear srv_file_per_table.

innobase_file_per_table: Remove.

handler/ha_innodb.cc

@@ -139,7 +139,6 @@ static char*	innobase_log_arch_dir			= NULL;
 #endif /* UNIV_LOG_ARCHIVE */
 static my_bool	innobase_use_doublewrite		= TRUE;
 static my_bool	innobase_use_checksums			= TRUE;
-static my_bool	innobase_file_per_table			= FALSE;
 static my_bool	innobase_locks_unsafe_for_binlog	= FALSE;
 static my_bool	innobase_rollback_on_timeout		= FALSE;
 static my_bool	innobase_create_status_file		= FALSE;
@@ -1751,7 +1750,6 @@ innobase_init(
 
 	row_rollback_on_timeout = (ibool) innobase_rollback_on_timeout;
 
-	srv_file_per_table = (ibool) innobase_file_per_table;
 	srv_locks_unsafe_for_binlog = (ibool) innobase_locks_unsafe_for_binlog;
 
 	srv_max_n_open_files = (ulint) innobase_open_files;
@@ -8320,8 +8318,8 @@ static MYSQL_SYSVAR_ULONG(fast_shutdown, innobase_fast_shutdown,
   ".",
   NULL, NULL, 1, 0, IF_NETWARE(1,2), 0);
 
-static MYSQL_SYSVAR_BOOL(file_per_table, innobase_file_per_table,
-  PLUGIN_VAR_NOCMDARG | PLUGIN_VAR_READONLY,
+static MYSQL_SYSVAR_BOOL(file_per_table, srv_file_per_table,
+  PLUGIN_VAR_NOCMDARG,
   "Stores each InnoDB table to an .ibd file in the database dir.",
   NULL, NULL, FALSE);
 

include/srv0srv.h

@@ -57,7 +57,11 @@ extern char*	srv_data_home;
 extern char*	srv_arch_dir;
 #endif /* UNIV_LOG_ARCHIVE */
 
-extern ibool	srv_file_per_table;
+/* store to its own file each table created by an user; data
+dictionary tables are in the system tablespace 0 */
+extern my_bool	srv_file_per_table;
+/* Place locks to records only i.e. do not use next-key locking except
+on duplicate key checking and foreign key checking */
 extern ibool	srv_locks_unsafe_for_binlog;
 
 extern ulint	srv_n_data_files;

srv/srv0srv.c

@@ -87,7 +87,7 @@ UNIV_INTERN char*	srv_arch_dir	= NULL;
 
 /* store to its own file each table created by an user; data
 dictionary tables are in the system tablespace 0 */
-UNIV_INTERN ibool	srv_file_per_table = FALSE;
+UNIV_INTERN my_bool	srv_file_per_table;
 /* Place locks to records only i.e. do not use next-key locking except
 on duplicate key checking and foreign key checking */
 UNIV_INTERN ibool	srv_locks_unsafe_for_binlog = FALSE;

srv/srv0start.c

@@ -979,7 +979,7 @@ innobase_start_or_create_for_mysql(void)
 	ulint		tablespace_size_in_header;
 	ulint		err;
 	ulint		i;
-	ibool		srv_file_per_table_original_value
+	my_bool		srv_file_per_table_original_value
 		= srv_file_per_table;
 	mtr_t		mtr;
 #ifdef HAVE_DARWIN_THREADS
@@ -1015,8 +1015,11 @@ innobase_start_or_create_for_mysql(void)
 			(ulong)sizeof(ulint), (ulong)sizeof(void*));
 	}
 
-	srv_file_per_table = FALSE; /* system tables are created in tablespace
-				    0 */
+	/* System tables are created in tablespace 0.  Thus, we must
+	temporarily clear srv_file_per_table.  This is ok, because the
+	server will not accept connections (which could modify
+	innodb_file_per_table) until this function has returned. */
+	srv_file_per_table = FALSE;
 #ifdef UNIV_DEBUG
 	fprintf(stderr,
 		"InnoDB: !!!!!!!! UNIV_DEBUG switched on !!!!!!!!!\n");