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-rwxr-xr-xC/Bcj2.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/C/Bcj2.c b/C/Bcj2.c
new file mode 100755
index 0000000..474bdd4
--- /dev/null
+++ b/C/Bcj2.c
@@ -0,0 +1,132 @@
+/* Bcj2.c -- Converter for x86 code (BCJ2)
+2008-10-04 : Igor Pavlov : Public domain */
+
+#include "Bcj2.h"
+
+#ifdef _LZMA_PROB32
+#define CProb UInt32
+#else
+#define CProb UInt16
+#endif
+
+#define IsJcc(b0, b1) ((b0) == 0x0F && ((b1) & 0xF0) == 0x80)
+#define IsJ(b0, b1) ((b1 & 0xFE) == 0xE8 || IsJcc(b0, b1))
+
+#define kNumTopBits 24
+#define kTopValue ((UInt32)1 << kNumTopBits)
+
+#define kNumBitModelTotalBits 11
+#define kBitModelTotal (1 << kNumBitModelTotalBits)
+#define kNumMoveBits 5
+
+#define RC_READ_BYTE (*buffer++)
+#define RC_TEST { if (buffer == bufferLim) return SZ_ERROR_DATA; }
+#define RC_INIT2 code = 0; range = 0xFFFFFFFF; \
+ { int i; for (i = 0; i < 5; i++) { RC_TEST; code = (code << 8) | RC_READ_BYTE; }}
+
+#define NORMALIZE if (range < kTopValue) { RC_TEST; range <<= 8; code = (code << 8) | RC_READ_BYTE; }
+
+#define IF_BIT_0(p) ttt = *(p); bound = (range >> kNumBitModelTotalBits) * ttt; if (code < bound)
+#define UPDATE_0(p) range = bound; *(p) = (CProb)(ttt + ((kBitModelTotal - ttt) >> kNumMoveBits)); NORMALIZE;
+#define UPDATE_1(p) range -= bound; code -= bound; *(p) = (CProb)(ttt - (ttt >> kNumMoveBits)); NORMALIZE;
+
+int Bcj2_Decode(
+ const Byte *buf0, SizeT size0,
+ const Byte *buf1, SizeT size1,
+ const Byte *buf2, SizeT size2,
+ const Byte *buf3, SizeT size3,
+ Byte *outBuf, SizeT outSize)
+{
+ CProb p[256 + 2];
+ SizeT inPos = 0, outPos = 0;
+
+ const Byte *buffer, *bufferLim;
+ UInt32 range, code;
+ Byte prevByte = 0;
+
+ unsigned int i;
+ for (i = 0; i < sizeof(p) / sizeof(p[0]); i++)
+ p[i] = kBitModelTotal >> 1;
+
+ buffer = buf3;
+ bufferLim = buffer + size3;
+ RC_INIT2
+
+ if (outSize == 0)
+ return SZ_OK;
+
+ for (;;)
+ {
+ Byte b;
+ CProb *prob;
+ UInt32 bound;
+ UInt32 ttt;
+
+ SizeT limit = size0 - inPos;
+ if (outSize - outPos < limit)
+ limit = outSize - outPos;
+ while (limit != 0)
+ {
+ Byte b = buf0[inPos];
+ outBuf[outPos++] = b;
+ if (IsJ(prevByte, b))
+ break;
+ inPos++;
+ prevByte = b;
+ limit--;
+ }
+
+ if (limit == 0 || outPos == outSize)
+ break;
+
+ b = buf0[inPos++];
+
+ if (b == 0xE8)
+ prob = p + prevByte;
+ else if (b == 0xE9)
+ prob = p + 256;
+ else
+ prob = p + 257;
+
+ IF_BIT_0(prob)
+ {
+ UPDATE_0(prob)
+ prevByte = b;
+ }
+ else
+ {
+ UInt32 dest;
+ const Byte *v;
+ UPDATE_1(prob)
+ if (b == 0xE8)
+ {
+ v = buf1;
+ if (size1 < 4)
+ return SZ_ERROR_DATA;
+ buf1 += 4;
+ size1 -= 4;
+ }
+ else
+ {
+ v = buf2;
+ if (size2 < 4)
+ return SZ_ERROR_DATA;
+ buf2 += 4;
+ size2 -= 4;
+ }
+ dest = (((UInt32)v[0] << 24) | ((UInt32)v[1] << 16) |
+ ((UInt32)v[2] << 8) | ((UInt32)v[3])) - ((UInt32)outPos + 4);
+ outBuf[outPos++] = (Byte)dest;
+ if (outPos == outSize)
+ break;
+ outBuf[outPos++] = (Byte)(dest >> 8);
+ if (outPos == outSize)
+ break;
+ outBuf[outPos++] = (Byte)(dest >> 16);
+ if (outPos == outSize)
+ break;
+ outBuf[outPos++] = prevByte = (Byte)(dest >> 24);
+ }
+ }
+ return (outPos == outSize) ? SZ_OK : SZ_ERROR_DATA;
+}