Stuck/leak when allocating data for NSData? - iphone

Question

I'm stuck at this method and I don't know why!
Can anyone point me to some source code?
Thank you so much!
This is my source code:
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc]init];
.......
readData = [readFileHandle readDataOfLength:defaultLen]
NSData *decryptedData = nil;
//check is last buffer of file
NSUInteger exLen = [readData length] % 16;
NSUInteger decryptionLen = [readData length] - exLen;
NSData *dataForDecryption = nil;
if(exLen != 0)
{
stuck at here-> [readData getBytes:dataForDecryption length:decryptionLen];
//
decryptedData = [dataForDecryption AES256DecryptWithKey:KEY];
self.isEndOfFile = YES;
}
else
decryptedData = [readData AES256DecryptWithKey:KEY];
[readFileHandle closeFile];
.......
[pool drain];
I've used some functions such as:
NSData *dataForDecryption = [[[NSData alloc] initWithBytes:readData length:decryptionLen]autorelease];
NSData *dataForDecryption = [NSData dataWithBytes:readData length:decryptionLen];
But I get the same error.
When i'm using
dataForDecryption = [readFileHandle readDataOfLength:decryptionLen];
it's stuck at pos above and the size read is 0, although it's not EOF.
Thanks

Answer 1

stuck at here-> [readData getBytes:dataForDecryption length:decryptionLen];
You're passing dataForDecryption, which is a NSData*, but the parameter is supposed to be a buffer, i.e. void*. If you want a NSData*, you should instead use a method like subdataWithRange:.
dataForEncryption = [readData subdataWithRange:NSRangeMake(0, decryptionLen)];