CFStringRef FileMD5HashCreateWithPath(CFStringRef filePath,
size_t chunkSizeForReadingData) { // Declare needed variables
CFStringRef result = NULL;
CFReadStreamRef readStream = NULL; // Get the file URL
CFURLRef fileURL =
CFURLCreateWithFileSystemPath(kCFAllocatorDefault,
(CFStringRef)filePath,
kCFURLPOSIXPathStyle,
(Boolean)false);
if (!fileURL) goto done; // Create and open the read stream
readStream = CFReadStreamCreateWithFile(kCFAllocatorDefault,
(CFURLRef)fileURL);
if (!readStream) goto done;
bool didSucceed = (bool)CFReadStreamOpen(readStream);
if (!didSucceed) goto done; // Initialize the hash object
CC_MD5_CTX hashObject;
CC_MD5_Init(&hashObject); // Make sure chunkSizeForReadingData is valid
if (!chunkSizeForReadingData) {
chunkSizeForReadingData = FileHashDefaultChunkSizeForReadingData;
} // Feed the data to the hash object
bool hasMoreData = true;
while (hasMoreData) {
uint8_t buffer[chunkSizeForReadingData];
CFIndex readBytesCount = CFReadStreamRead(readStream,
(UInt8 *)buffer,
(CFIndex)sizeof(buffer));
if (readBytesCount == -) break;
if (readBytesCount == ) {
hasMoreData = false;
continue;
}
CC_MD5_Update(&hashObject,(const void *)buffer,(CC_LONG)readBytesCount);
} // Check if the read operation succeeded
didSucceed = !hasMoreData; // Compute the hash digest
unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5_Final(digest, &hashObject); // Abort if the read operation failed
if (!didSucceed) goto done; // Compute the string result
char hash[ * sizeof(digest) + ];
for (size_t i = ; i < sizeof(digest); ++i) {
snprintf(hash + ( * i), , "%02x", (int)(digest[i]));
}
result = CFStringCreateWithCString(kCFAllocatorDefault,
(const char *)hash,
kCFStringEncodingUTF8); done: if (readStream) {
CFReadStreamClose(readStream);
CFRelease(readStream);
}
if (fileURL) {
CFRelease(fileURL);
}
return result;
} +(NSString*)fileMD5:(NSString*)path
{
return (__bridge_transfer NSString *)FileMD5HashCreateWithPath((__bridge CFStringRef)path, FileHashDefaultChunkSizeForReadingData);
}