| commit | author | age | ||
| 6e1425 | 1 | // |
| H | 2 | // FMDatabasePool.h |
| 3 | // fmdb | |
| 4 | // | |
| 5 | // Created by August Mueller on 6/22/11. | |
| 6 | // Copyright 2011 Flying Meat Inc. All rights reserved. | |
| 7 | // | |
| 8 | ||
| 9 | #import <Foundation/Foundation.h> | |
| 10 | ||
| 11 | @class FMDatabase; | |
| 12 | ||
| 13 | /** Pool of `<FMDatabase>` objects. | |
| 14 | ||
| 15 | ### See also | |
| 16 | ||
| 17 | - `<FMDatabaseQueue>` | |
| 18 | - `<FMDatabase>` | |
| 19 | ||
| 20 | @warning Before using `FMDatabasePool`, please consider using `<FMDatabaseQueue>` instead. | |
| 21 | ||
| 22 | If you really really really know what you're doing and `FMDatabasePool` is what | |
| 23 | you really really need (ie, you're using a read only database), OK you can use | |
| 24 | it. But just be careful not to deadlock! | |
| 25 | ||
| 26 | For an example on deadlocking, search for: | |
| 27 | `ONLY_USE_THE_POOL_IF_YOU_ARE_DOING_READS_OTHERWISE_YOULL_DEADLOCK_USE_FMDATABASEQUEUE_INSTEAD` | |
| 28 | in the main.m file. | |
| 29 | */ | |
| 30 | ||
| 31 | @interface FMDatabasePool : NSObject { | |
| 32 | NSString *_path; | |
| 33 | ||
| 34 | dispatch_queue_t _lockQueue; | |
| 35 | ||
| 36 | NSMutableArray *_databaseInPool; | |
| 37 | NSMutableArray *_databaseOutPool; | |
| 38 | ||
| 39 | __unsafe_unretained id _delegate; | |
| 40 | ||
| 41 | NSUInteger _maximumNumberOfDatabasesToCreate; | |
| 42 | int _openFlags; | |
| 43 | } | |
| 44 | ||
| 45 | /** Database path */ | |
| 46 | ||
| 47 | @property (atomic, retain) NSString *path; | |
| 48 | ||
| 49 | /** Delegate object */ | |
| 50 | ||
| 51 | @property (atomic, assign) id delegate; | |
| 52 | ||
| 53 | /** Maximum number of databases to create */ | |
| 54 | ||
| 55 | @property (atomic, assign) NSUInteger maximumNumberOfDatabasesToCreate; | |
| 56 | ||
| 57 | /** Open flags */ | |
| 58 | ||
| 59 | @property (atomic, readonly) int openFlags; | |
| 60 | ||
| 61 | ||
| 62 | ///--------------------- | |
| 63 | /// @name Initialization | |
| 64 | ///--------------------- | |
| 65 | ||
| 66 | /** Create pool using path. | |
| 67 | ||
| 68 | @param aPath The file path of the database. | |
| 69 | ||
| 70 | @return The `FMDatabasePool` object. `nil` on error. | |
| 71 | */ | |
| 72 | ||
| 73 | + (instancetype)databasePoolWithPath:(NSString*)aPath; | |
| 74 | ||
| 75 | /** Create pool using path and specified flags | |
| 76 | ||
| 77 | @param aPath The file path of the database. | |
| 78 | @param openFlags Flags passed to the openWithFlags method of the database | |
| 79 | ||
| 80 | @return The `FMDatabasePool` object. `nil` on error. | |
| 81 | */ | |
| 82 | ||
| 83 | + (instancetype)databasePoolWithPath:(NSString*)aPath flags:(int)openFlags; | |
| 84 | ||
| 85 | /** Create pool using path. | |
| 86 | ||
| 87 | @param aPath The file path of the database. | |
| 88 | ||
| 89 | @return The `FMDatabasePool` object. `nil` on error. | |
| 90 | */ | |
| 91 | ||
| 92 | - (instancetype)initWithPath:(NSString*)aPath; | |
| 93 | ||
| 94 | /** Create pool using path and specified flags. | |
| 95 | ||
| 96 | @param aPath The file path of the database. | |
| 97 | @param openFlags Flags passed to the openWithFlags method of the database | |
| 98 | ||
| 99 | @return The `FMDatabasePool` object. `nil` on error. | |
| 100 | */ | |
| 101 | ||
| 102 | - (instancetype)initWithPath:(NSString*)aPath flags:(int)openFlags; | |
| 103 | ||
| 104 | ///------------------------------------------------ | |
| 105 | /// @name Keeping track of checked in/out databases | |
| 106 | ///------------------------------------------------ | |
| 107 | ||
| 108 | /** Number of checked-in databases in pool | |
| 109 | ||
| 110 | @returns Number of databases | |
| 111 | */ | |
| 112 | ||
| 113 | - (NSUInteger)countOfCheckedInDatabases; | |
| 114 | ||
| 115 | /** Number of checked-out databases in pool | |
| 116 | ||
| 117 | @returns Number of databases | |
| 118 | */ | |
| 119 | ||
| 120 | - (NSUInteger)countOfCheckedOutDatabases; | |
| 121 | ||
| 122 | /** Total number of databases in pool | |
| 123 | ||
| 124 | @returns Number of databases | |
| 125 | */ | |
| 126 | ||
| 127 | - (NSUInteger)countOfOpenDatabases; | |
| 128 | ||
| 129 | /** Release all databases in pool */ | |
| 130 | ||
| 131 | - (void)releaseAllDatabases; | |
| 132 | ||
| 133 | ///------------------------------------------ | |
| 134 | /// @name Perform database operations in pool | |
| 135 | ///------------------------------------------ | |
| 136 | ||
| 137 | /** Synchronously perform database operations in pool. | |
| 138 | ||
| 139 | @param block The code to be run on the `FMDatabasePool` pool. | |
| 140 | */ | |
| 141 | ||
| 142 | - (void)inDatabase:(void (^)(FMDatabase *db))block; | |
| 143 | ||
| 144 | /** Synchronously perform database operations in pool using transaction. | |
| 145 | ||
| 146 | @param block The code to be run on the `FMDatabasePool` pool. | |
| 147 | */ | |
| 148 | ||
| 149 | - (void)inTransaction:(void (^)(FMDatabase *db, BOOL *rollback))block; | |
| 150 | ||
| 151 | /** Synchronously perform database operations in pool using deferred transaction. | |
| 152 | ||
| 153 | @param block The code to be run on the `FMDatabasePool` pool. | |
| 154 | */ | |
| 155 | ||
| 156 | - (void)inDeferredTransaction:(void (^)(FMDatabase *db, BOOL *rollback))block; | |
| 157 | ||
| 158 | /** Synchronously perform database operations in pool using save point. | |
| 159 | ||
| 160 | @param block The code to be run on the `FMDatabasePool` pool. | |
| 161 | ||
| 162 | @return `NSError` object if error; `nil` if successful. | |
| 163 | ||
| 164 | @warning 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 startSavePointWithName:error:]>` instead. | |
| 165 | */ | |
| 166 | ||
| 167 | - (NSError*)inSavePoint:(void (^)(FMDatabase *db, BOOL *rollback))block; | |
| 168 | ||
| 169 | @end | |
| 170 | ||
| 171 | ||
| 172 | /** FMDatabasePool delegate category | |
| 173 | ||
| 174 | This is a category that defines the protocol for the FMDatabasePool delegate | |
| 175 | */ | |
| 176 | ||
| 177 | @interface NSObject (FMDatabasePoolDelegate) | |
| 178 | ||
| 179 | /** Asks the delegate whether database should be added to the pool. | |
| 180 | ||
| 181 | @param pool The `FMDatabasePool` object. | |
| 182 | @param database The `FMDatabase` object. | |
| 183 | ||
| 184 | @return `YES` if it should add database to pool; `NO` if not. | |
| 185 | ||
| 186 | */ | |
| 187 | ||
| 188 | - (BOOL)databasePool:(FMDatabasePool*)pool shouldAddDatabaseToPool:(FMDatabase*)database; | |
| 189 | ||
| 190 | /** Tells the delegate that database was added to the pool. | |
| 191 | ||
| 192 | @param pool The `FMDatabasePool` object. | |
| 193 | @param database The `FMDatabase` object. | |
| 194 | ||
| 195 | */ | |
| 196 | ||
| 197 | - (void)databasePool:(FMDatabasePool*)pool didAddDatabase:(FMDatabase*)database; | |
| 198 | ||
| 199 | @end | |
| 200 | ||
