All credit goes to Stack Overflow user UrK for the answer here: http://stackoverflow.com/a/19311779/862224
@interface LineNumberLogFormatter : NSObject<DDLogFormatter>
- (NSString *)formatLogMessage:(DDLogMessage *)logMessage;
@end
@implementation LineNumberLogFormatter
- (NSString *)formatLogMessage:(DDLogMessage *)logMessage
{
NSString *path = [NSString stringWithCString:logMessage->file encoding:NSASCIIStringEncoding];
NSString *fileName = [path lastPathComponent];
return [NSString stringWithFormat:@"%@:%d %@", fileName, logMessage->lineNumber, logMessage->logMsg];
}
@end