Block device from sleeping during certain activities.

// FREEBIE

Signal.xcodeproj/project.pbxproj

@@ -34,6 +34,7 @@
 		3456710A1E8A9F5D006EE662 /* TSGenericAttachmentAdapter.m in Sources */ = {isa = PBXBuildFile; fileRef = 345671091E8A9F5D006EE662 /* TSGenericAttachmentAdapter.m */; };
 		3471B1DA1EB7C63600F6AEC8 /* NewNonContactConversationViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 3471B1D91EB7C63600F6AEC8 /* NewNonContactConversationViewController.m */; };
 		3472229F1EB22FFE00E53955 /* AddToGroupViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 3472229E1EB22FFE00E53955 /* AddToGroupViewController.m */; };
+		348F2EAE1F0D21BC00D4ECE0 /* DeviceSleepManager.swift in Sources */ = {isa = PBXBuildFile; fileRef = 348F2EAD1F0D21BC00D4ECE0 /* DeviceSleepManager.swift */; };
 		3497DBEC1ECE257500DB2605 /* OWSCountryMetadata.m in Sources */ = {isa = PBXBuildFile; fileRef = 3497DBEB1ECE257500DB2605 /* OWSCountryMetadata.m */; };
 		3497DBEF1ECE2E4700DB2605 /* DomainFrontingCountryViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 3497DBEE1ECE2E4700DB2605 /* DomainFrontingCountryViewController.m */; };
 		34B3F8711E8DF1700035BE1A /* AboutTableViewController.m in Sources */ = {isa = PBXBuildFile; fileRef = 34B3F8351E8DF1700035BE1A /* AboutTableViewController.m */; };
@@ -414,6 +415,7 @@
 		3471B1D91EB7C63600F6AEC8 /* NewNonContactConversationViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = NewNonContactConversationViewController.m; sourceTree = "<group>"; };
 		3472229D1EB22FFE00E53955 /* AddToGroupViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = AddToGroupViewController.h; sourceTree = "<group>"; };
 		3472229E1EB22FFE00E53955 /* AddToGroupViewController.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = AddToGroupViewController.m; sourceTree = "<group>"; };
+		348F2EAD1F0D21BC00D4ECE0 /* DeviceSleepManager.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = DeviceSleepManager.swift; sourceTree = "<group>"; };
 		3497DBEA1ECE257500DB2605 /* OWSCountryMetadata.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OWSCountryMetadata.h; sourceTree = "<group>"; };
 		3497DBEB1ECE257500DB2605 /* OWSCountryMetadata.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OWSCountryMetadata.m; sourceTree = "<group>"; };
 		3497DBED1ECE2E4700DB2605 /* DomainFrontingCountryViewController.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = DomainFrontingCountryViewController.h; sourceTree = "<group>"; };
@@ -1326,6 +1328,7 @@
 				76EB04CF18170B33006006FC /* collections */,
 				B90418E4183E9DD40038554A /* DateUtil.h */,
 				B90418E5183E9DD40038554A /* DateUtil.m */,
+				348F2EAD1F0D21BC00D4ECE0 /* DeviceSleepManager.swift */,
 				45E615151E8C590B0018AD52 /* DisplayableTextFilter.swift */,
 				76EB04EA18170B33006006FC /* FunctionalUtil.h */,
 				76EB04EB18170B33006006FC /* FunctionalUtil.m */,
@@ -2126,6 +2129,7 @@
 				34B3F8931E8DF1710035BE1A /* SignalsNavigationController.m in Sources */,
 				76EB063A18170B33006006FC /* FunctionalUtil.m in Sources */,
 				34F308A21ECB469700BB7697 /* OWSBezierPathView.m in Sources */,
+				348F2EAE1F0D21BC00D4ECE0 /* DeviceSleepManager.swift in Sources */,
 				34E3EF101EFC2684007F6822 /* DebugUIPage.m in Sources */,
 				34E8BF3B1EEB208E00F5F4CA /* DebugUIVerification.m in Sources */,
 				76EB058A18170B33006006FC /* Release.m in Sources */,

Signal/src/ViewControllers/ConversationView/MessagesViewController.m

@@ -3628,6 +3628,18 @@ typedef enum : NSUInteger {
     self.voiceMessageUUID = nil;
 }
 
+- (void)setAudioRecorder:(AVAudioRecorder *)audioRecorder
+{
+    // Prevent device from sleeping while recording a voice message.
+    if (audioRecorder) {
+        [DeviceSleepManager.sharedInstance addBlockWithBlockObject:audioRecorder];
+    } else if (_audioRecorder) {
+        [DeviceSleepManager.sharedInstance removeBlockWithBlockObject:_audioRecorder];
+    }
+
+    _audioRecorder = audioRecorder;
+}
+
 #pragma mark Accessory View
 
 - (void)didPressAccessoryButton:(UIButton *)sender

Signal/src/ViewControllers/OWSAudioAttachmentPlayer.m

@@ -82,6 +82,8 @@ NS_ASSUME_NONNULL_BEGIN
 {
     [[NSNotificationCenter defaultCenter] removeObserver:self];
 
+    [DeviceSleepManager.sharedInstance removeBlockWithBlockObject:self];
+
     [self stop];
 }
 
@@ -133,6 +135,9 @@ NS_ASSUME_NONNULL_BEGIN
                                                                 selector:@selector(audioPlayerUpdated:)
                                                                 userInfo:nil
                                                                  repeats:YES];
+
+    // Prevent device from sleeping while playing audio.
+    [DeviceSleepManager.sharedInstance addBlockWithBlockObject:self];
 }
 
 - (void)pause
@@ -145,6 +150,8 @@ NS_ASSUME_NONNULL_BEGIN
     [self.audioPlayerPoller invalidate];
     [self.delegate setAudioProgress:[self.audioPlayer currentTime] duration:[self.audioPlayer duration]];
     [self.delegate setAudioIconToPlay];
+
+    [DeviceSleepManager.sharedInstance removeBlockWithBlockObject:self];
 }
 
 - (void)stop
@@ -157,6 +164,8 @@ NS_ASSUME_NONNULL_BEGIN
     [self.delegate setAudioIconToPlay];
     self.delegate.isAudioPlaying = NO;
     self.delegate.isPaused = NO;
+
+    [DeviceSleepManager.sharedInstance removeBlockWithBlockObject:self];
 }
 
 - (void)togglePlayState

Signal/src/call/CallService.swift

@@ -138,7 +138,16 @@ protocol CallServiceObserver: class {
             call?.addObserverAndSyncState(observer: self)
 
             updateIsVideoEnabled()
-            updateLockTimerEnabling()
+
+            // Prevent device from sleeping while we have an active call.
+            if oldValue != call {
+                if let oldValue = oldValue {
+                    DeviceSleepManager.sharedInstance.removeBlock(blockObject: oldValue)
+                }
+                if let call = call {
+                    DeviceSleepManager.sharedInstance.addBlock(blockObject: call)
+                }
+            }
 
             Logger.debug("\(self.TAG) .call setter: \(oldValue?.identifiersForLogs as Optional) -> \(call?.identifiersForLogs as Optional)")
 
@@ -1351,16 +1360,6 @@ protocol CallServiceObserver: class {
                                                  remoteVideoTrack:remoteVideoTrack)
         }
     }
-
-    private func updateLockTimerEnabling() {
-        AssertIsOnMainThread()
-
-        // Prevent screen from dimming during call.
-        //
-        // Note that this state has no effect if app is in the background.
-        let hasCall = call != nil
-        UIApplication.shared.isIdleTimerDisabled = hasCall
-    }
 }
 
 fileprivate extension MessageSender {

Signal/src/util/DeviceSleepManager.swift

@@ -0,0 +1,81 @@
+//
+//  Copyright (c) 2017 Open Whisper Systems. All rights reserved.
+//
+
+import Foundation
+
+// This entity has responsibility for blocking the device from sleeping if
+// certain behaviors (e.g. recording or playing voice messages) are in progress.
+// 
+// Sleep blocking is keyed using "block objects" whose lifetime correponds to
+// the duration of the block.  For example, sleep blocking during audio playback
+// can be keyed to the audio player.  This provides a measure of robustness.
+// On the one hand, we can use weak references to track block objects and stop
+// blocking if the block object is deallocated even if removeBlock() is not
+// called.  On the other hand, we will also get correct behavior to addBlock()
+// being called twice with the same block object.
+@objc class DeviceSleepManager: NSObject {
+
+    let TAG = "[DeviceSleepManager]"
+
+    static let sharedInstance = DeviceSleepManager()
+
+    private class SleepBlock {
+        weak var blockObject: NSObject?
+
+        init(blockObject: NSObject) {
+            self.blockObject = blockObject
+        }
+    }
+    private var blocks: [SleepBlock] = []
+
+    override init() {
+        super.init()
+
+        NotificationCenter.default.addObserver(self,
+                                               selector:#selector(didEnterBackground),
+                                               name:NSNotification.Name.UIApplicationDidEnterBackground,
+                                               object:nil)
+    }
+
+    deinit {
+        NotificationCenter.default.removeObserver(self)
+    }
+
+    func didEnterBackground() {
+        AssertIsOnMainThread()
+
+        ensureSleepBlocking()
+    }
+
+    public func addBlock(blockObject: NSObject) {
+        blocks.append(SleepBlock(blockObject: blockObject))
+
+        ensureSleepBlocking()
+    }
+
+    public func removeBlock(blockObject: NSObject) {
+        blocks = blocks.filter {
+         $0.blockObject != nil && $0.blockObject != blockObject
+        }
+
+        ensureSleepBlocking()
+    }
+
+    private func ensureSleepBlocking() {
+        // Cull expired blocks.
+        blocks = blocks.filter {
+            $0.blockObject != nil
+        }
+        let shouldBlock = blocks.count > 0
+
+        if UIApplication.shared.isIdleTimerDisabled != shouldBlock {
+            if shouldBlock {
+                Logger.info("\(self.TAG) \(#function): Blocking sleep")
+            } else {
+                Logger.info("\(self.TAG) \(#function): Unblocking sleep")
+            }
+        }
+        UIApplication.shared.isIdleTimerDisabled = shouldBlock
+    }
+}