FileSize Problem - Cocoa

Question

Hello,

I've written methods that help me get the size of files/folders and translate the result in a human readable string. Problem is, when this size exceeds about 2.1GB, the number returned changes to a random negative number, like "-4324234423 bytes", which is useless.

Things I've found out about & done about this issue:

• 32GB is limited to this size, so I compile in 64bit instead.
• I've tried using both CGFloat and NSUInteger, but both still return the same value as NSInteger.

I am quite frustrated, I don't know what I am missing. Here are my methods:

- (NSString *)stringFromFileSize:(int)theSize
{
 CGFloat floatSize = theSize;
 if (theSize<1023)
  return([NSString stringWithFormat:@"%i bytes",theSize]);
 floatSize = floatSize / 1024;
 if (floatSize<1023)
  return([NSString stringWithFormat:@"%1.1f KB",floatSize]);
 floatSize = floatSize / 1024;
 if (floatSize<1023)
  return([NSString stringWithFormat:@"%1.2f MB",floatSize]);
 floatSize = floatSize / 1024;

 return([NSString stringWithFormat:@"%1.2f GB",floatSize]);
}

- (NSUInteger)sizeOfFile:(NSString *)path
{
 NSDictionary *fattrib = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil];
 NSUInteger fileSize = (NSUInteger)[fattrib fileSize];
 return fileSize;
}

- (NSUInteger)sizeOfFolder:(NSString*)folderPath
{
 NSArray *contents;
 NSEnumerator *enumerator;
 NSString *path;
 contents = [[NSFileManager defaultManager] subpathsAtPath:folderPath];
 enumerator = [contents objectEnumerator];
 NSUInteger fileSizeInt = 0;
 while (path = [enumerator nextObject]) {
  NSDictionary *fattrib = [[NSFileManager defaultManager] attributesOfItemAtPath:[folderPath stringByAppendingPathComponent:path] error:nil];
  fileSizeInt +=[fattrib fileSize];
 }
 return fileSizeInt;
}

What am I missing? Is NSFileManager returning a 32bit value? What's causing this?

Thanks!

Answer 1

Alas, nearly all systems have "int" being 32-bit, even if you "compile for 64-bit". (Windows, Mac and Linux work this way). See http://en.wikipedia.org/wiki/64-bit#Specific_C-language_data_models.

You can either pass long to your stringFromFileSize method, or you can pass a NSUInteger.