Adding Crunch at r319.

third_party/crunch/crnlib/lzma_7zCrc.cpp

@@ -0,0 +1,40 @@
+/* 7zCrc.c -- CRC32 calculation
+2008-08-05
+Igor Pavlov
+Public domain */
+#include "crn_core.h"
+
+#include "lzma_7zCrc.h"
+
+namespace crnlib {
+
+#define kCrcPoly 0xEDB88320
+UInt32 g_CrcTable[256];
+
+void MY_FAST_CALL CrcGenerateTable(void)
+{
+  UInt32 i;
+  for (i = 0; i < 256; i++)
+  {
+    UInt32 r = i;
+    int j;
+    for (j = 0; j < 8; j++)
+      r = (r >> 1) ^ (kCrcPoly & ~((r & 1) - 1));
+    g_CrcTable[i] = r;
+  }
+}
+
+UInt32 MY_FAST_CALL CrcUpdate(UInt32 v, const void *data, size_t size)
+{
+  const Byte *p = (const Byte *)data;
+  for (; size > 0 ; size--, p++)
+    v = CRC_UPDATE_BYTE(v, *p);
+  return v;
+}
+
+UInt32 MY_FAST_CALL CrcCalc(const void *data, size_t size)
+{
+  return CrcUpdate(CRC_INIT_VAL, data, size) ^ 0xFFFFFFFF;
+}
+
+}