VPatch 3.0

git-svn-id: https://svn.code.sf.net/p/nsis/code/NSIS/trunk@4271 212acab6-be3b-0410-9dea-997c60f758d6

Contrib/VPatch/Source/Plugin/checksum.c

@@ -0,0 +1,115 @@
+//---------------------------------------------------------------------------
+// checksum.c
+//---------------------------------------------------------------------------
+//                           -=* VPatch *=-
+//---------------------------------------------------------------------------
+// Copyright (C) 2001-2005 Koen van de Sande / Van de Sande Productions
+//---------------------------------------------------------------------------
+// Website: http://www.tibed.net/vpatch
+//
+// This software is provided 'as-is', without any express or implied
+// warranty.  In no event will the authors be held liable for any damages
+// arising from the use of this software.
+//
+// Permission is granted to anyone to use this software for any purpose,
+// including commercial applications, and to alter it and redistribute it
+// freely, subject to the following restrictions:
+//
+// 1. The origin of this software must not be misrepresented; you must not
+//    claim that you wrote the original software. If you use this software
+//    in a product, an acknowledgment in the product documentation would be
+//    appreciated but is not required.
+// 2. Altered source versions must be plainly marked as such, and must not be
+//    misrepresented as being the original software.
+// 3. This notice may not be removed or altered from any source distribution.
+
+#include "checksum.h"
+
+/* ------------------------ CRC32 checksum calculation ----------------- */
+
+UINT CRCTable[256];
+BOOL bInitCRC = FALSE;
+
+_inline void InitCRC() {
+  int i, j; unsigned long c;
+  for (c = i = 0; i < 256; c = ++i) {
+    for (j = 0; j < 8; j++) {
+      if (c & 1) c = (c>>1) ^ 0xEDB88320;
+      else       c >>= 1;
+    }
+    CRCTable[i] = c;
+  }
+  bInitCRC = TRUE;
+}
+
+#define CRCBLOCKSIZE    4096
+
+BOOL FileCRC(HANDLE hFile, DWORD *crc) {
+  static BYTE crcblock[CRCBLOCKSIZE];
+  DWORD read;
+  BYTE *p;
+
+  UINT c = 0xFFFFFFFF;
+  if (bInitCRC == FALSE)
+    InitCRC();
+  
+  SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+  do {
+    if (ReadFile(hFile, crcblock, CRCBLOCKSIZE, &read, NULL) == FALSE)
+      return FALSE;
+    for (p = crcblock; p < crcblock + read; p++)
+      c = CRCTable[(c & 0xFF) ^ *p] ^ (c >> 8);
+  } while (read);
+
+  *crc = (c ^ 0xFFFFFFFF);
+
+  return TRUE;
+}
+
+void CRC32ToString(char* string, DWORD crc) {
+  int i = 0;
+  int j = 7;
+  int a1, a2;
+  for(i = 0; i < 4; i++) {
+    a1 = (crc >> 4) % 16;
+    a2 = crc % 16;
+    string[j--] = a2 < 10 ? ('0' + a2) : ('A' + a2 - 10);
+    string[j--] = a1 < 10 ? ('0' + a1) : ('A' + a1 - 10);
+    crc = crc >> 8;
+  }
+}
+
+/* ------------------------ MD5 checksum calculation ----------------- */
+
+#define MD5BLOCKSIZE    16384
+
+BOOL FileMD5(HANDLE hFile, md5_byte_t digest[16]) {
+  static BYTE md5block[MD5BLOCKSIZE];
+  DWORD read;
+
+  md5_state_t state;
+  
+  md5_init(&state);
+ 
+  SetFilePointer(hFile, 0, NULL, FILE_BEGIN);
+  do {
+    if (ReadFile(hFile, md5block, MD5BLOCKSIZE, &read, NULL) == FALSE)
+      return FALSE;
+    md5_append(&state, md5block, read);
+  } while (read);
+
+  md5_finish(&state, digest);
+  return TRUE;
+}
+
+void MD5ToString(char* string, md5_byte_t checksum[16]) {
+  int i = 0;
+  int j = 0;
+  int a1, a2;
+  for(i = 0; i < 16; i++) {
+    a1 = (checksum[i] >> 4) % 16;
+    a2 = checksum[i] % 16;
+    string[j++] = a1 < 10 ? ('0' + a1) : ('A' + a1 - 10);
+    string[j++] = a2 < 10 ? ('0' + a2) : ('A' + a2 - 10);
+  }
+}