Changes between Version 32 and Version 33 of HashSourceCodes

Timestamp:

Jan 5, 2011, 11:15:58 AM (14 years ago)

Author:

os

Comment:

--

HashSourceCodes

@@ -1160 +1160 @@
 Calc_Hash endp
 }}}
+
+== Objective-C ==
+This is implementation of hash for Objective-C for Mac by subsmarine.com
+
+'''OSHashAlgorithm.m'''
+{{{
+#import "OSHashAlgorithm.h"
+
+
+@implementation OSHashAlgorithm
+
++(NSString*)stringForHash:(uint64_t)hash
+{
+        return [[NSString stringWithFormat:@"%qx", hash ] autorelease];
+}
++(VideoHash)hashForPath:(NSString*)path
+{
+        VideoHash hash;
+        hash.fileHash =0;
+        hash.fileSize =0;
+        
+        NSFileHandle *readFile = [NSFileHandle fileHandleForReadingAtPath:path];
+        hash = [OSHashAlgorithm hashForFile:readFile];
+        [readFile closeFile];
+        return hash;    
+}
++(VideoHash)hashForURL:(NSURL*)url
+{
+        VideoHash hash;
+        hash.fileHash =0;
+        hash.fileSize =0;
+        
+        NSFileHandle *readfile = [NSFileHandle fileHandleForReadingFromURL:url error:NULL];
+        hash = [OSHashAlgorithm hashForFile:readfile];
+        return hash;
+}
+
++(VideoHash)hashForFile:(NSFileHandle*)handle
+{
+        VideoHash retHash;
+        retHash.fileHash =0;
+        retHash.fileSize =0;
+        
+        if( handle == nil )
+                return retHash;
+        
+        const NSUInteger CHUNK_SIZE=65536;
+        NSData *fileDataBegin, *fileDataEnd;
+        uint64_t hash=0;
+        
+        
+        fileDataBegin = [handle readDataOfLength:(NSUInteger)CHUNK_SIZE];
+        [handle seekToEndOfFile];
+        unsigned long long fileSize = [handle offsetInFile];
+        if(fileSize < CHUNK_SIZE )
+                return retHash;
+        
+        [handle seekToFileOffset:MAX(0,fileSize-CHUNK_SIZE) ];
+        fileDataEnd = [handle readDataOfLength:(NSUInteger)CHUNK_SIZE];
+        
+        //
+        // Calculate hash
+        //
+        
+        // 1st. File size
+        hash += fileSize;
+        // 2nd. Begining data block
+        uint64_t * data_bytes= (uint64_t*)[fileDataBegin bytes]; 
+        for( int i=0; i< CHUNK_SIZE/sizeof(uint64_t); i++ )
+                hash+=data_bytes[i];;
+        // 3rd. Ending data block
+        data_bytes= (uint64_t*)[fileDataEnd bytes]; 
+        for( int i=0; i< CHUNK_SIZE/sizeof(uint64_t); i++ )
+                hash+= data_bytes[i];
+        
+        retHash.fileHash = hash;
+        retHash.fileSize = fileSize;
+        
+        return retHash;
+        
+}
+
+@end
+}}}
+
+
+
+'''OSHashAlgorithm.h'''
+{{{
+#import <Cocoa/Cocoa.h>
+
+typedef struct 
+{
+        uint64_t fileHash;
+        uint64_t fileSize;
+} VideoHash;
+
+@interface OSHashAlgorithm : NSObject {
+
+}
++(VideoHash)hashForPath:(NSString*)path;
++(VideoHash)hashForURL:(NSURL*)url;
++(VideoHash)hashForFile:(NSFileHandle*)handle;
++(NSString*)stringForHash:(uint64_t)hash;
+
+@end
+}}}