63 lines
1.9 KiB
Objective-C
63 lines
1.9 KiB
Objective-C
//
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// Copyright (c) 2018 Open Whisper Systems. All rights reserved.
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//
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#import <Foundation/Foundation.h>
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NS_ASSUME_NONNULL_BEGIN
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typedef NS_ENUM(NSUInteger, BackgroundTaskState) {
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BackgroundTaskState_Success,
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BackgroundTaskState_CouldNotStart,
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BackgroundTaskState_Expired,
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};
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typedef void (^BackgroundTaskCompletionBlock)(BackgroundTaskState backgroundTaskState);
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// This class can be safely accessed and used from any thread.
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@interface OWSBackgroundTaskManager : NSObject
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- (instancetype)init NS_UNAVAILABLE;
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+ (instancetype)sharedManager;
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- (void)observeNotifications;
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@end
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#pragma mark -
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// This class makes it easier and safer to use background tasks.
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//
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// * Uses RAII (Resource Acquisition Is Initialization) pattern.
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// * Ensures completion block is called exactly once and on main thread,
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// to facilitate handling "background task timed out" case, for example.
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// * Ensures we properly handle the "background task could not be created"
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// case.
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//
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// Usage:
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//
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// * Use factory method to start a background task.
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// * Retain a strong reference to the OWSBackgroundTask during the "work".
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// * Clear all references to the OWSBackgroundTask when the work is done,
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// if possible.
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@interface OWSBackgroundTask : NSObject
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- (instancetype)init NS_UNAVAILABLE;
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+ (OWSBackgroundTask *)backgroundTaskWithLabelStr:(const char *)labelStr;
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// completionBlock will be called exactly once on the main thread.
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+ (OWSBackgroundTask *)backgroundTaskWithLabelStr:(const char *)labelStr
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completionBlock:(BackgroundTaskCompletionBlock)completionBlock;
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+ (OWSBackgroundTask *)backgroundTaskWithLabel:(NSString *)label;
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// completionBlock will be called exactly once on the main thread.
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+ (OWSBackgroundTask *)backgroundTaskWithLabel:(NSString *)label
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completionBlock:(BackgroundTaskCompletionBlock)completionBlock;
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@end
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NS_ASSUME_NONNULL_END
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