/*
|
* This file is part of the SDWebImage package.
|
* (c) Olivier Poitrey <rs@dailymotion.com>
|
*
|
* For the full copyright and license information, please view the LICENSE
|
* file that was distributed with this source code.
|
*/
|
|
|
#import "SDWebImageCompat.h"
|
|
/// SDCallbackPolicy controls how we execute the block on the queue, like whether to use `dispatch_async/dispatch_sync`, check if current queue match target queue, or just invoke without any context.
|
typedef NS_ENUM(NSUInteger, SDCallbackPolicy) {
|
/// When the current queue is equal to callback queue, sync/async will just invoke `block` directly without dispatch. Else it use `dispatch_async`/`dispatch_sync` to dispatch block on queue. This is useful for UIKit rendering to ensure all blocks executed in the same runloop
|
SDCallbackPolicySafeExecute = 0,
|
/// Follow async/sync using the correspond `dispatch_async`/`dispatch_sync` to dispatch block on queue
|
SDCallbackPolicyDispatch = 1,
|
/// Ignore any async/sync and just directly invoke `block` in current queue (without `dispatch_async`/`dispatch_sync`)
|
SDCallbackPolicyInvoke = 2
|
};
|
|
/// SDCallbackQueue is a wrapper used to control how the completionBlock should perform on queues, used by our `Cache`/`Manager`/`Loader`.
|
/// Useful when you call SDWebImage in non-main queue and want to avoid it callback into main queue, which may cause issue.
|
@interface SDCallbackQueue : NSObject
|
|
/// The shared main queue. This is the default value, has the same effect when passing `nil` to `SDWebImageContextCallbackQueue`
|
@property (nonnull, class, readonly) SDCallbackQueue *mainQueue;
|
|
/// The caller current queue. Using `dispatch_get_current_queue`. This is not a dynamic value and only keep the first call time queue.
|
@property (nonnull, class, readonly) SDCallbackQueue *currentQueue;
|
|
/// The global concurrent queue (user-initiated QoS). Using `dispatch_get_global_queue`.
|
@property (nonnull, class, readonly) SDCallbackQueue *globalQueue;
|
|
/// The current queue's callback policy, defaults to `SDCallbackPolicySafeExecute`, which behaves like the old macro `dispatch_main_async_safe`
|
@property (assign, readwrite) SDCallbackPolicy policy;
|
|
- (nonnull instancetype)init NS_UNAVAILABLE;
|
+ (nonnull instancetype)new NS_UNAVAILABLE;
|
/// Create the callback queue with a GCD queue
|
/// - Parameter queue: The GCD queue, should not be NULL
|
- (nonnull instancetype)initWithDispatchQueue:(nonnull dispatch_queue_t)queue NS_DESIGNATED_INITIALIZER;
|
|
#pragma mark - Execution Entry
|
|
/// Submits a block for execution and returns after that block finishes executing.
|
/// - Parameter block: The block that contains the work to perform.
|
- (void)sync:(nonnull dispatch_block_t)block;
|
|
/// Schedules a block asynchronously for execution.
|
/// - Parameter block: The block that contains the work to perform.
|
- (void)async:(nonnull dispatch_block_t)block;
|
|
@end
|
