iOS Core Foundation Memory Leak in External Library - ios

Question

I'm currently trying to write an application using an open-source, external library. I have the source code available to it, and can build myself a fresh copy whenever needed.
Anyway, while profiling my application - I noticed that some memory was leaking in the library. It's small - 128b a shot - but still, I'd prefer not to have memory leaks to begin with.
Here's the code. The modified code that I wrote is on top (that leaks), and the original code is on bottom (that leaks).
CFURLRef getURLFromPath(const char * path) {
//modified code to hopefully clean up after myself
CFStringRef cfTotalPath = CFStringCreateWithCString (NULL, path, kCFStringEncodingUTF8);
CFURLRef cURL = CFURLCreateWithFileSystemPath(NULL, cfTotalPath, kCFURLPOSIXPathStyle, false);
CFRelease(cfTotalPath);
return cURL;
//original code
/*CFStringRef cfTotalPath = CFStringCreateWithCString (kCFAllocatorDefault,
path, kCFStringEncodingUTF8);
return CFURLCreateWithFileSystemPath(kCFAllocatorDefault, cfTotalPath,
kCFURLPOSIXPathStyle, false);*/
}
I'm relatively new to iOS programming; I'm debugging on an actual device, and I know that sometimes Instruments gives false-positives when it comes to leaks.
This is infuriating, because this one block of code is the last step in the stack trace for my leaks... and I honestly do not know how to fix it.
EDIT: From what I've read, Apple doesn't mind the occasional memory leak here and there; I'll continue programming, because this process only happens once per music file in my application - analyzing a track for the BPM (it gets saved once analyzed).
Edit2: Here's the referring code. I've added all of the CFRelease(fileURL), but it still leaks:
uint_t aubio_sink_apple_audio_open(aubio_sink_apple_audio_t *s) {
if (s->samplerate == 0 || s->channels == 0) return AUBIO_FAIL;
AudioStreamBasicDescription clientFormat;
memset(&clientFormat, 0, sizeof(AudioStreamBasicDescription));
clientFormat.mFormatID = kAudioFormatLinearPCM;
clientFormat.mSampleRate = (Float64)(s->samplerate);
clientFormat.mFormatFlags = kAudioFormatFlagIsSignedInteger | kAudioFormatFlagIsPacked;
clientFormat.mChannelsPerFrame = s->channels;
clientFormat.mBitsPerChannel = sizeof(short) * 8;
clientFormat.mFramesPerPacket = 1;
clientFormat.mBytesPerFrame = clientFormat.mBitsPerChannel * clientFormat.mChannelsPerFrame / 8;
clientFormat.mBytesPerPacket = clientFormat.mFramesPerPacket * clientFormat.mBytesPerFrame;
clientFormat.mReserved = 0;
AudioFileTypeID fileType = kAudioFileWAVEType;
CFURLRef fileURL = getURLFromPath(s->path);
bool overwrite = true;
OSStatus err = noErr;
err = ExtAudioFileCreateWithURL(fileURL, fileType, &clientFormat, NULL,
overwrite ? kAudioFileFlags_EraseFile : 0, &s->audioFile);
if (err) {
char_t errorstr[20];
AUBIO_ERR("sink_apple_audio: error when trying to create %s with "
"ExtAudioFileCreateWithURL (%s)\n", s->path,
getPrintableOSStatusError(errorstr, err));
goto beach;
}
if (createAubioBufferList(&s->bufferList, s->channels, s->max_frames * s->channels)) {
AUBIO_ERR("sink_apple_audio: error when creating buffer list for %s, "
"out of memory? \n", s->path);
goto beach;
}
//added release code
CFRelease(fileURL);
return AUBIO_OK;
beach:
//added release code
CFRelease(fileURL);
return AUBIO_FAIL;
}
EDIT3: Here's a screenshot
EDIT4: The original solution actually works, XCode refused to load the new version of my framework even though I kept recompiling it. So, I had to purge all references of the framework - including scrubbing the Build info pages - and re-add the "fixed" version.

Answer 1

You are leaking the returned CFURLRef created with CFURLCreateWithFileSystemPath.
You should rename the function from getURLFromPath to createURLFromPath to indicate that ownership of the returned CFURLRef is being passed on to the caller. Then any code that calls the method is responsible for releasing the CFURLRef when done with it.