1 files changed, 85 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/C/Ppmd.h b/other-licenses/7zstub/src/C/Ppmd.h
new file mode 100644
index 000000000..4b9941521
--- /dev/null
+++ b/other-licenses/7zstub/src/C/Ppmd.h
@@ -0,0 +1,85 @@
+/* Ppmd.h -- PPMD codec common code
+2017-04-03 : Igor Pavlov : Public domain
+This code is based on PPMd var.H (2001): Dmitry Shkarin : Public domain */
+
+#ifndef __PPMD_H
+#define __PPMD_H
+
+#include "CpuArch.h"
+
+EXTERN_C_BEGIN
+
+#ifdef MY_CPU_32BIT
+  #define PPMD_32BIT
+#endif
+
+#define PPMD_INT_BITS 7
+#define PPMD_PERIOD_BITS 7
+#define PPMD_BIN_SCALE (1 << (PPMD_INT_BITS + PPMD_PERIOD_BITS))
+
+#define PPMD_GET_MEAN_SPEC(summ, shift, round) (((summ) + (1 << ((shift) - (round)))) >> (shift))
+#define PPMD_GET_MEAN(summ) PPMD_GET_MEAN_SPEC((summ), PPMD_PERIOD_BITS, 2)
+#define PPMD_UPDATE_PROB_0(prob) ((prob) + (1 << PPMD_INT_BITS) - PPMD_GET_MEAN(prob))
+#define PPMD_UPDATE_PROB_1(prob) ((prob) - PPMD_GET_MEAN(prob))
+
+#define PPMD_N1 4
+#define PPMD_N2 4
+#define PPMD_N3 4
+#define PPMD_N4 ((128 + 3 - 1 * PPMD_N1 - 2 * PPMD_N2 - 3 * PPMD_N3) / 4)
+#define PPMD_NUM_INDEXES (PPMD_N1 + PPMD_N2 + PPMD_N3 + PPMD_N4)
+
+#pragma pack(push, 1)
+/* Most compilers works OK here even without #pragma pack(push, 1), but some GCC compilers need it. */
+
+/* SEE-contexts for PPM-contexts with masked symbols */
+typedef struct
+{
+  UInt16 Summ; /* Freq */
+  Byte Shift;  /* Speed of Freq change; low Shift is for fast change */
+  Byte Count;  /* Count to next change of Shift */
+} CPpmd_See;
+
+#define Ppmd_See_Update(p)  if ((p)->Shift < PPMD_PERIOD_BITS && --(p)->Count == 0) \
+    { (p)->Summ <<= 1; (p)->Count = (Byte)(3 << (p)->Shift++); }
+
+typedef struct
+{
+  Byte Symbol;
+  Byte Freq;
+  UInt16 SuccessorLow;
+  UInt16 SuccessorHigh;
+} CPpmd_State;
+
+#pragma pack(pop)
+
+typedef
+  #ifdef PPMD_32BIT
+    CPpmd_State *
+  #else
+    UInt32
+  #endif
+  CPpmd_State_Ref;
+
+typedef
+  #ifdef PPMD_32BIT
+    void *
+  #else
+    UInt32
+  #endif
+  CPpmd_Void_Ref;
+
+typedef
+  #ifdef PPMD_32BIT
+    Byte *
+  #else
+    UInt32
+  #endif
+  CPpmd_Byte_Ref;
+
+#define PPMD_SetAllBitsIn256Bytes(p) \
+  { size_t z; for (z = 0; z < 256 / sizeof(p[0]); z += 8) { \
+  p[z+7] = p[z+6] = p[z+5] = p[z+4] = p[z+3] = p[z+2] = p[z+1] = p[z+0] = ~(size_t)0; }}
+
+EXTERN_C_END
+ 
+#endif