Merge pull request #1535 from nextcloud/add-optional-filedescriptor-l…

…ogging

Add optional logging of socket file descriptors

NextcloudTalk/AppDelegate.m

@@ -52,6 +52,7 @@ @interface AppDelegate ()
 @property (nonatomic, strong) BGTaskHelper *keepAliveBGTask;
 @property (nonatomic, strong) UILabel *debugLabel;
 @property (nonatomic, strong) NSTimer *debugLabelTimer;
+@property (nonatomic, strong) NSTimer *fileDescriptorTimer;
 
 @end
 
@@ -107,6 +108,13 @@ - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(
         }];
     }
 
+    // Comment out the following code to log the number of open socket file descriptors
+    /*
+     self.fileDescriptorTimer = [NSTimer scheduledTimerWithTimeInterval:1 repeats:YES block:^(NSTimer * _Nonnull timer) {
+        [[WebRTCCommon shared] printNumberOfOpenSocketDescriptors];
+    }];
+     */
+
     // When we include VLCKit we need to manually call this because otherwise, device rotation might not work
     [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications];
 
@@ -167,6 +175,8 @@ - (void)applicationWillTerminate:(UIApplication *)application
 
     // Invalidate a potentially existing label timer
     [self.debugLabelTimer invalidate];
+
+    [self.fileDescriptorTimer invalidate];
 }
 
 - (BOOL)application:(UIApplication *)app openURL:(NSURL *)url options:(NSDictionary<UIApplicationOpenURLOptionsKey,id> *)options

NextcloudTalk/WebRTCCommon.swift

@@ -51,4 +51,27 @@ import Foundation
     public func assertQueue() {
         dispatchPrecondition(condition: .onQueue(webrtcClientDispatchQueue))
     }
+
+    public func printNumberOfOpenSocketDescriptors() {
+        print("File descriptors: \(self.openFilePaths().filter { $0 == "?" }.count)")
+    }
+
+    private func openFilePaths() -> [String] {
+        // from https://developer.apple.com/forums/thread/655225?answerId=623114022#623114022
+        (0..<getdtablesize()).map { fd in
+            // Return "" for invalid file descriptors.
+            var flags: CInt = 0
+            guard fcntl(fd, F_GETFL, &flags) >= 0 else {
+                return ""
+            }
+            // Return "?" for file descriptors not associated with a path, for
+            // example, a socket.
+            var path = [CChar](repeating: 0, count: Int(MAXPATHLEN))
+            guard fcntl(fd, F_GETPATH, &path) >= 0 else {
+                return "?"
+            }
+
+            return String(cString: path)
+        }
+    }
 }