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-rw-r--r--src/app/Splitter/crc32.cpp69
1 files changed, 69 insertions, 0 deletions
diff --git a/src/app/Splitter/crc32.cpp b/src/app/Splitter/crc32.cpp
new file mode 100644
index 0000000..b6b807b
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+++ b/src/app/Splitter/crc32.cpp
@@ -0,0 +1,69 @@
+/***************************************************************************
+ crc32.cpp - description
+ -------------------
+ copyright : (C) 2003 by Csaba Karai
+ e-mail : krusader@users.sourceforge.net
+ web site : http://krusader.sourceforge.net
+ ---------------------------------------------------------------------------
+ Description
+ ***************************************************************************
+
+ A
+
+ db dD d8888b. db db .d8888. .d8b. d8888b. d88888b d8888b.
+ 88 ,8P' 88 `8D 88 88 88' YP d8' `8b 88 `8D 88' 88 `8D
+ 88,8P 88oobY' 88 88 `8bo. 88ooo88 88 88 88ooooo 88oobY'
+ 88`8b 88`8b 88 88 `Y8b. 88~~~88 88 88 88~~~~~ 88`8b
+ 88 `88. 88 `88. 88b d88 db 8D 88 88 88 .8D 88. 88 `88.
+ YP YD 88 YD ~Y8888P' `8888Y' YP YP Y8888D' Y88888P 88 YD
+
+ S o u r c e F i l e
+
+ ***************************************************************************
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation; either version 2 of the License, or *
+ * (at your option) any later version. *
+ * *
+ ***************************************************************************/
+
+#include "crc32.h"
+
+#define MASK1 0x00FFFFFF
+#define MASK2 0xFFFFFFFF
+#define POLYNOMIAL 0xEDB88320
+
+bool CRC32::crc_initialized = false;
+unsigned long CRC32::crc_table[ 256 ];
+
+CRC32::CRC32( unsigned long initialValue )
+{
+ crc_accum = initialValue;
+
+ if( !crc_initialized )
+ {
+ for( int byte = 0; byte != 256; byte++ )
+ {
+ unsigned long data = byte;
+
+ for( int i = 8; i > 0 ; --i )
+ data = data & 1 ? ( data >> 1 ) ^ POLYNOMIAL : data >> 1;
+
+ crc_table[ byte ] = data;
+ }
+
+ crc_initialized = true;
+ }
+}
+
+void CRC32::update( unsigned char *buffer, int bufferLen )
+{
+ while( bufferLen-- > 0 )
+ crc_accum = ( (crc_accum >> 8) & MASK1 ) ^ crc_table[ (crc_accum & 0xff) ^ *buffer++ ];
+}
+
+unsigned long CRC32::result()
+{
+ return ( ~crc_accum ) & MASK2;
+}