AppRTCDemo file logging.

talk/app/webrtc/objc/public/RTCFileLogger.h

Index: talk/app/webrtc/objc/public/RTCFileLogger.h
diff --git a/talk/examples/objc/AppRTCDemo/ARDSDPUtils.h b/talk/app/webrtc/objc/public/RTCFileLogger.h
similarity index 62%
copy from talk/examples/objc/AppRTCDemo/ARDSDPUtils.h
copy to talk/app/webrtc/objc/public/RTCFileLogger.h
index 2f14e6dec0b40b77b1f6d03be0ef639387b4d0db..59c52052c54621f54a5fb19aca69eb3addfceeec 100644
--- a/talk/examples/objc/AppRTCDemo/ARDSDPUtils.h
+++ b/talk/app/webrtc/objc/public/RTCFileLogger.h
@@ -27,15 +27,31 @@
 
 #import <Foundation/Foundation.h>
 
-@class RTCSessionDescription;
+// TODO(tkchin): Move this to a common location.
+#ifndef NS_DESIGNATED_INITIALIZER
+#define NS_DESIGNATED_INITIALIZER
+#endif
 
-@interface ARDSDPUtils : NSObject
+// This class intercepts WebRTC logs and saves them to a file. The file size
+// will not exceed the given maximum bytesize. When the maximum bytesize is
+// reached logs from the beginning and the end are preserved while the middle
+// section is overwritten instead.
+@interface RTCFileLogger : NSObject
 
-// Updates the original SDP description to instead prefer the specified video
-// codec. We do this by placing the specified codec at the beginning of the
-// codec list if it exists in the sdp.
-+ (RTCSessionDescription *)
-    descriptionForDescription:(RTCSessionDescription *)description
-          preferredVideoCodec:(NSString *)codec;
+// Default constructor provides default settings for file path and file size.
+- (instancetype)init;
+
+- (instancetype)initWithFilePath:(NSString *)filePath
+                     maxFileSize:(NSUInteger)maxFileSize NS_DESIGNATED_INITIALIZER;
+
+// Starts writing WebRTC logs to file if not already started. Overwrites any
+// existing file.
+- (void)start;
+
+// Stops writing WebRTC logs to file.
+- (void)stop;
+
+// Returns the contents of the written log file.
+- (NSString *)log;
 
 @end