Add oldest rotation type option to RTCFileLogger

BUG=

Review URL: https://codereview.webrtc.org/1432753003

Cr-Commit-Position: refs/heads/master@{#10945}

talk/app/webrtc/objc/RTCFileLogger.mm

@@ -35,15 +35,17 @@
 
 NSString *const kDefaultLogDirName = @"webrtc_logs";
 NSUInteger const kDefaultMaxFileSize = 10 * 1024 * 1024; // 10MB.
+const char *kRTCFileLoggerRotatingLogPrefix = "rotating_log";
 
 @implementation RTCFileLogger {
   BOOL _hasStarted;
   NSString *_dirPath;
   NSUInteger _maxFileSize;
-  rtc::scoped_ptr<rtc::CallSessionFileRotatingLogSink> _logSink;
+  rtc::scoped_ptr<rtc::FileRotatingLogSink> _logSink;
 }
 
 @synthesize severity = _severity;
+@synthesize rotationType = _rotationType;
 
 - (instancetype)init {
   NSArray *paths = NSSearchPathForDirectoriesInDomains(
@@ -57,6 +59,14 @@ NSUInteger const kDefaultMaxFileSize = 10 * 1024 * 1024; // 10MB.
 
 - (instancetype)initWithDirPath:(NSString *)dirPath
                     maxFileSize:(NSUInteger)maxFileSize {
+  return [self initWithDirPath:dirPath
+                   maxFileSize:maxFileSize
+                  rotationType:kRTCFileLoggerTypeCall];
+}
+
+- (instancetype)initWithDirPath:(NSString *)dirPath
+                    maxFileSize:(NSUInteger)maxFileSize
+                   rotationType:(RTCFileLoggerRotationType)rotationType {
   NSParameterAssert(dirPath.length);
   NSParameterAssert(maxFileSize);
   if (self = [super init]) {
@@ -91,8 +101,20 @@ NSUInteger const kDefaultMaxFileSize = 10 * 1024 * 1024; // 10MB.
   if (_hasStarted) {
     return;
   }
-  _logSink.reset(new rtc::CallSessionFileRotatingLogSink(_dirPath.UTF8String,
-                                                         _maxFileSize));
+  switch (_rotationType) {
+    case kRTCFileLoggerTypeApp:
+      _logSink.reset(
+          new rtc::FileRotatingLogSink(_dirPath.UTF8String,
+                                       kRTCFileLoggerRotatingLogPrefix,
+                                       _maxFileSize,
+                                       _maxFileSize / 10));
+      break;
+    case kRTCFileLoggerTypeCall:
+      _logSink.reset(
+          new rtc::CallSessionFileRotatingLogSink(_dirPath.UTF8String,
+                                                  _maxFileSize));
+      break;
+  }
   if (!_logSink->Init()) {
     LOG(LS_ERROR) << "Failed to open log files at path: "
                   << _dirPath.UTF8String;
@@ -120,8 +142,17 @@ NSUInteger const kDefaultMaxFileSize = 10 * 1024 * 1024; // 10MB.
     return nil;
   }
   NSMutableData* logData = [NSMutableData data];
-  rtc::scoped_ptr<rtc::CallSessionFileRotatingStream> stream(
-      new rtc::CallSessionFileRotatingStream(_dirPath.UTF8String));
+  rtc::scoped_ptr<rtc::FileRotatingStream> stream;
+  switch(_rotationType) {
+    case kRTCFileLoggerTypeApp:
+      stream.reset(
+          new rtc::FileRotatingStream(_dirPath.UTF8String,
+                                      kRTCFileLoggerRotatingLogPrefix));
+      break;
+    case kRTCFileLoggerTypeCall:
+      stream.reset(new rtc::CallSessionFileRotatingStream(_dirPath.UTF8String));
+      break;
+  }
   if (!stream->Open()) {
     return logData;
   }

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

@@ -39,21 +39,38 @@ typedef NS_ENUM(NSUInteger, RTCFileLoggerSeverity) {
   kRTCFileLoggerSeverityError
 };
 
+typedef NS_ENUM(NSUInteger, RTCFileLoggerRotationType) {
+  kRTCFileLoggerTypeCall,
+  kRTCFileLoggerTypeApp,
+};
+
 // 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.
+// reached, logs are rotated according to the rotationType specified.
+// For kRTCFileLoggerTypeCall, logs from the beginning and the end
+// are preserved while the middle section is overwritten instead.
+// For kRTCFileLoggerTypeApp, the oldest log is overwritten.
 // This class is not threadsafe.
 @interface RTCFileLogger : NSObject
 
 // The severity level to capture. The default is kRTCFileLoggerSeverityInfo.
 @property(nonatomic, assign) RTCFileLoggerSeverity severity;
 
-// Default constructor provides default settings for dir path and file size.
+// The rotation type for this file logger. The default is
+// kRTCFileLoggerTypeCall.
+@property(nonatomic, readonly) RTCFileLoggerRotationType rotationType;
+
+// Default constructor provides default settings for dir path, file size and
+// rotation type.
 - (instancetype)init;
 
+// Create file logger with default rotation type.
+- (instancetype)initWithDirPath:(NSString *)dirPath
+                    maxFileSize:(NSUInteger)maxFileSize;
+
 - (instancetype)initWithDirPath:(NSString *)dirPath
                     maxFileSize:(NSUInteger)maxFileSize
+                   rotationType:(RTCFileLoggerRotationType)rotationType
     NS_DESIGNATED_INITIALIZER;
 
 // Starts writing WebRTC logs to disk if not already started. Overwrites any

webrtc/base/filerotatingstream.cc

@@ -281,7 +281,7 @@ void FileRotatingStream::RotateFiles() {
   // Rotates the files by deleting the file at |rotation_index_|, which is the
   // oldest file and then renaming the newer files to have an incremented index.
   // See header file comments for example.
-  RTC_DCHECK_LE(rotation_index_, file_names_.size());
+  RTC_DCHECK_LT(rotation_index_, file_names_.size());
   std::string file_to_delete = file_names_[rotation_index_];
   if (Filesystem::IsFile(file_to_delete)) {
     if (!Filesystem::DeleteFile(file_to_delete)) {