WASdkImpl_CN.git

			@@ -7,73 +7,78 @@
			//

			#import <Foundation/Foundation.h>
			#import "FMDatabase.h"

			@class FMDatabase;
			NS_ASSUME_NONNULL_BEGIN

			/** To perform queries and updates on multiple threads, you'll want to use `FMDatabaseQueue`.
			/** To perform queries and updates on multiple threads, you'll want to use @c FMDatabaseQueue .

			Using a single instance of `<FMDatabase>` from multiple threads at once is a bad idea. It has always been OK to make a `<FMDatabase>` object per thread. Just don't share a single instance across threads, and definitely not across multiple threads at the same time.
			Using a single instance of @c FMDatabase from multiple threads at once is a bad idea. It has always been OK to make a @c FMDatabase object per thread. Just don't share a single instance across threads, and definitely not across multiple threads at the same time.

			Instead, use `FMDatabaseQueue`. Here's how to use it:
			Instead, use @c FMDatabaseQueue . Here's how to use it:

			First, make your queue.

			FMDatabaseQueue *queue = [FMDatabaseQueue databaseQueueWithPath:aPath];
			@code
			FMDatabaseQueue *queue = [FMDatabaseQueue databaseQueueWithPath:aPath];
			@endcode

			Then use it like so:

			[queue inDatabase:^(FMDatabase *db) {
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:1]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:2]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:3]];
			@code
			[queue inDatabase:^(FMDatabase *db) {
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:1]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:2]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:3]];

			FMResultSet rs = [db executeQuery:@"select from foo"];
			while ([rs next]) {
			//…
			}
			}];
			FMResultSet rs = [db executeQuery:@"select from foo"];
			while ([rs next]) {
			//…
			}
			}];
			@endcode

			An easy way to wrap things up in a transaction can be done like this:

			[queue inTransaction:^(FMDatabase db, BOOL rollback) {
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:1]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:2]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:3]];
			@code
			[queue inTransaction:^(FMDatabase db, BOOL rollback) {
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:1]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:2]];
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:3]];

			if (whoopsSomethingWrongHappened) {
			*rollback = YES;
			return;
			}
			// etc…
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:4]];
			}];
			// if (whoopsSomethingWrongHappened) {
			// *rollback = YES;
			// return;
			// }

			`FMDatabaseQueue` will run the blocks on a serialized queue (hence the name of the class). So if you call `FMDatabaseQueue`'s methods from multiple threads at the same time, they will be executed in the order they are received. This way queries and updates won't step on each other's toes, and every one is happy.
			// etc…
			[db executeUpdate:@"INSERT INTO myTable VALUES (?)", [NSNumber numberWithInt:4]];
			}];
			@endcode

			### See also
			@c FMDatabaseQueue will run the blocks on a serialized queue (hence the name of the class). So if you call @c FMDatabaseQueue 's methods from multiple threads at the same time, they will be executed in the order they are received. This way queries and updates won't step on each other's toes, and every one is happy.

			- `<FMDatabase>`

			@warning Do not instantiate a single `<FMDatabase>` object and use it across multiple threads. Use `FMDatabaseQueue` instead.
			@warning Do not instantiate a single @c FMDatabase object and use it across multiple threads. Use @c FMDatabaseQueue instead.

			@warning The calls to `FMDatabaseQueue`'s methods are blocking. So even though you are passing along blocks, they will not be run on another thread.
			@warning The calls to @c FMDatabaseQueue 's methods are blocking. So even though you are passing along blocks, they will not be run on another thread.

			@sa FMDatabase

			*/

			@interface FMDatabaseQueue : NSObject {
			NSString *_path;
			dispatch_queue_t _queue;
			FMDatabase *_db;
			int _openFlags;
			}
			@interface FMDatabaseQueue : NSObject

			/** Path of database */

			@property (atomic, retain) NSString *path;
			@property (atomic, retain, nullable) NSString *path;

			/** Open flags */

			@property (atomic, readonly) int openFlags;

			/** Custom virtual file system name */

			@property (atomic, copy, nullable) NSString *vfsName;

			///----------------------------------------------------
			/// @name Initialization, opening, and closing of queue
			@@ -83,38 +88,75 @@

			@param aPath The file path of the database.

			@return The `FMDatabaseQueue` object. `nil` on error.
			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			+ (instancetype)databaseQueueWithPath:(NSString*)aPath;
			+ (nullable instancetype)databaseQueueWithPath:(NSString * _Nullable)aPath;

			/** Create queue using file URL.

			@param url The file @c NSURL of the database.

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			+ (nullable instancetype)databaseQueueWithURL:(NSURL * _Nullable)url;

			/** Create queue using path and specified flags.

			@param aPath The file path of the database.
			@param openFlags Flags passed to the openWithFlags method of the database
			@param openFlags Flags passed to the openWithFlags method of the database.

			@return The `FMDatabaseQueue` object. `nil` on error.
			@return The @c FMDatabaseQueue object. @c nil on error.
			*/
			+ (instancetype)databaseQueueWithPath:(NSString*)aPath flags:(int)openFlags;
			+ (nullable instancetype)databaseQueueWithPath:(NSString * _Nullable)aPath flags:(int)openFlags;

			/** Create queue using file URL and specified flags.

			@param url The file @c NSURL of the database.
			@param openFlags Flags passed to the openWithFlags method of the database.

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/
			+ (nullable instancetype)databaseQueueWithURL:(NSURL * _Nullable)url flags:(int)openFlags;

			/** Create queue using path.


			@param aPath The file path of the database.

			@return The `FMDatabaseQueue` object. `nil` on error.

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (instancetype)initWithPath:(NSString*)aPath;
			- (nullable instancetype)initWithPath:(NSString * _Nullable)aPath;

			/** Create queue using file URL.

			@param url The file `NSURL of the database.

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (nullable instancetype)initWithURL:(NSURL * _Nullable)url;

			/** Create queue using path and specified flags.

			@param aPath The file path of the database.
			@param openFlags Flags passed to the openWithFlags method of the database
			@param openFlags Flags passed to the openWithFlags method of the database.

			@return The `FMDatabaseQueue` object. `nil` on error.
			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (instancetype)initWithPath:(NSString*)aPath flags:(int)openFlags;
			- (nullable instancetype)initWithPath:(NSString * _Nullable)aPath flags:(int)openFlags;

			/** Create queue using file URL and specified flags.

			@param url The file path of the database.
			@param openFlags Flags passed to the openWithFlags method of the database.

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (nullable instancetype)initWithURL:(NSURL * _Nullable)url flags:(int)openFlags;

			/** Create queue using path and specified flags.

			@@ -122,10 +164,21 @@
			@param openFlags Flags passed to the openWithFlags method of the database
			@param vfsName The name of a custom virtual file system

			@return The `FMDatabaseQueue` object. `nil` on error.
			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (instancetype)initWithPath:(NSString)aPath flags:(int)openFlags vfs:(NSString )vfsName;
			- (nullable instancetype)initWithPath:(NSString * _Nullable)aPath flags:(int)openFlags vfs:(NSString * _Nullable)vfsName;

			/** Create queue using file URL and specified flags.

			@param url The file `NSURL of the database.
			@param openFlags Flags passed to the openWithFlags method of the database
			@param vfsName The name of a custom virtual file system

			@return The @c FMDatabaseQueue object. @c nil on error.
			*/

			- (nullable instancetype)initWithURL:(NSURL * _Nullable)url flags:(int)openFlags vfs:(NSString * _Nullable)vfsName;

			/** Returns the Class of 'FMDatabase' subclass, that will be used to instantiate database object.

			@@ -140,30 +193,57 @@

			- (void)close;

			/** Interupt pending database operation. */

			- (void)interrupt;

			///-----------------------------------------------
			/// @name Dispatching database operations to queue
			///-----------------------------------------------

			/** Synchronously perform database operations on queue.

			@param block The code to be run on the queue of `FMDatabaseQueue`
			@param block The code to be run on the queue of @c FMDatabaseQueue
			*/

			- (void)inDatabase:(void (^)(FMDatabase *db))block;
			- (void)inDatabase:(__attribute__((noescape)) void (^)(FMDatabase *db))block;

			/** Synchronously perform database operations on queue, using transactions.

			@param block The code to be run on the queue of `FMDatabaseQueue`
			@param block The code to be run on the queue of @c FMDatabaseQueue

			@warning Unlike SQLite's `BEGIN TRANSACTION`, this method currently performs
			an exclusive transaction, not a deferred transaction. This behavior
			is likely to change in future versions of FMDB, whereby this method
			will likely eventually adopt standard SQLite behavior and perform
			deferred transactions. If you really need exclusive tranaction, it is
			recommended that you use `inExclusiveTransaction`, instead, not only
			to make your intent explicit, but also to future-proof your code.

			*/

			- (void)inTransaction:(void (^)(FMDatabase db, BOOL rollback))block;
			- (void)inTransaction:(__attribute__((noescape)) void (^)(FMDatabase db, BOOL rollback))block;

			/** Synchronously perform database operations on queue, using deferred transactions.

			@param block The code to be run on the queue of `FMDatabaseQueue`

			@param block The code to be run on the queue of @c FMDatabaseQueue
			*/

			- (void)inDeferredTransaction:(void (^)(FMDatabase db, BOOL rollback))block;
			- (void)inDeferredTransaction:(__attribute__((noescape)) void (^)(FMDatabase db, BOOL rollback))block;

			/** Synchronously perform database operations on queue, using exclusive transactions.

			@param block The code to be run on the queue of @c FMDatabaseQueue
			*/

			- (void)inExclusiveTransaction:(__attribute__((noescape)) void (^)(FMDatabase db, BOOL rollback))block;

			/** Synchronously perform database operations on queue, using immediate transactions.

			@param block The code to be run on the queue of @c FMDatabaseQueue
			*/

			- (void)inImmediateTransaction:(__attribute__((noescape)) void (^)(FMDatabase db, BOOL rollback))block;

			///-----------------------------------------------
			/// @name Dispatching database operations to queue
			@@ -171,12 +251,45 @@

			/** Synchronously perform database operations using save point.

			@param block The code to be run on the queue of `FMDatabaseQueue`
			@param block The code to be run on the queue of @c FMDatabaseQueue
			*/

			// NOTE: you can not nest these, since calling it will pull another database out of the pool and you'll get a deadlock.
			// If you need to nest, use FMDatabase's startSavePointWithName:error: instead.
			- (NSError)inSavePoint:(void (^)(FMDatabase db, BOOL *rollback))block;
			- (NSError * _Nullable)inSavePoint:(__attribute__((noescape)) void (^)(FMDatabase db, BOOL rollback))block;

			///-----------------
			/// @name Checkpoint
			///-----------------

			/** Performs a WAL checkpoint

			@param checkpointMode The checkpoint mode for sqlite3_wal_checkpoint_v2
			@param error The NSError corresponding to the error, if any.
			@return YES on success, otherwise NO.
			*/
			- (BOOL)checkpoint:(FMDBCheckpointMode)checkpointMode error:(NSError * _Nullable *)error;

			/** Performs a WAL checkpoint

			@param checkpointMode The checkpoint mode for sqlite3_wal_checkpoint_v2
			@param name The db name for sqlite3_wal_checkpoint_v2
			@param error The NSError corresponding to the error, if any.
			@return YES on success, otherwise NO.
			*/
			- (BOOL)checkpoint:(FMDBCheckpointMode)checkpointMode name:(NSString * _Nullable)name error:(NSError * _Nullable *)error;

			/** Performs a WAL checkpoint

			@param checkpointMode The checkpoint mode for sqlite3_wal_checkpoint_v2
			@param name The db name for sqlite3_wal_checkpoint_v2
			@param error The NSError corresponding to the error, if any.
			@param logFrameCount If not NULL, then this is set to the total number of frames in the log file or to -1 if the checkpoint could not run because of an error or because the database is not in WAL mode.
			@param checkpointCount If not NULL, then this is set to the total number of checkpointed frames in the log file (including any that were already checkpointed before the function was called) or to -1 if the checkpoint could not run due to an error or because the database is not in WAL mode.
			@return YES on success, otherwise NO.
			*/
			- (BOOL)checkpoint:(FMDBCheckpointMode)checkpointMode name:(NSString * _Nullable)name logFrameCount:(int * _Nullable)logFrameCount checkpointCount:(int * _Nullable)checkpointCount error:(NSError * _Nullable *)error;

			@end

			NS_ASSUME_NONNULL_END