Gravatar for Iphone? How to create an MD5 hex hash?

Question

I would like to use gravatar in my application for iPhone. Is there a way to generate the hexadecimal MD5 hash in Objective-C for iPhone? Using openssl on iPhone is non-go.

Answer 1

Here's how I did it before uninstalling it from my application:

#import <CommonCrypto/CommonDigest.h>

NSString* md5( NSString *str ) {
  const char *cStr = [str UTF8String];
  unsigned char result[CC_MD5_DIGEST_LENGTH];

  CC_MD5( cStr, strlen(cStr), result );

  return [[NSString
      stringWithFormat:@"%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X%02X",
      result[0], result[1],
      result[2], result[3],
      result[4], result[5],
      result[6], result[7],
      result[8], result[9],
      result[10], result[11],
      result[12], result[13],
      result[14], result[15]
      ] lowercaseString];
}

One can only add that I myself did not write this. I found it somewhere on the Internet, but I did not record where.

Answer 2

, MD5-, github CommonCrypto. , , CommonCrypto, , base-64 ..

:

NSMutableString * str = [[NSMutableString alloc] initWithCapacity: 33];
int i;
for ( i = 0; i < 16; i++ )
{
  [str appendFormat: @"%02x", result[i]];
}
NSString * output = [str copy];
[str release];
return ( [output autorelease] );

, % 02X % 02x -lowercaseString - , .