aboutsummaryrefslogtreecommitdiffstats
path: root/libarchive/archive_ppmd8.c
diff options
context:
space:
mode:
Diffstat (limited to 'libarchive/archive_ppmd8.c')
-rw-r--r--libarchive/archive_ppmd8.c1287
1 files changed, 1287 insertions, 0 deletions
diff --git a/libarchive/archive_ppmd8.c b/libarchive/archive_ppmd8.c
new file mode 100644
index 000000000000..d1779395dac5
--- /dev/null
+++ b/libarchive/archive_ppmd8.c
@@ -0,0 +1,1287 @@
+/* Ppmd8.c -- PPMdI codec
+2016-05-21 : Igor Pavlov : Public domain
+This code is based on PPMd var.I (2002): Dmitry Shkarin : Public domain */
+
+#include "archive_platform.h"
+
+#include <string.h>
+
+#include "archive_ppmd8_private.h"
+
+const Byte PPMD8_kExpEscape[16] = { 25, 14, 9, 7, 5, 5, 4, 4, 4, 3, 3, 3, 2, 2, 2, 2 };
+static const UInt16 kInitBinEsc[] = { 0x3CDD, 0x1F3F, 0x59BF, 0x48F3, 0x64A1, 0x5ABC, 0x6632, 0x6051};
+
+#define MAX_FREQ 124
+#define UNIT_SIZE 12
+
+#define U2B(nu) ((UInt32)(nu) * UNIT_SIZE)
+#define U2I(nu) (p->Units2Indx[(nu) - 1])
+#define I2U(indx) (p->Indx2Units[indx])
+
+#ifdef PPMD_32BIT
+ #define REF(ptr) (ptr)
+#else
+ #define REF(ptr) ((UInt32)((Byte *)(ptr) - (p)->Base))
+#endif
+
+#define STATS_REF(ptr) ((CPpmd_State_Ref)REF(ptr))
+
+#define CTX(ref) ((CPpmd8_Context *)Ppmd8_GetContext(p, ref))
+#define STATS(ctx) Ppmd8_GetStats(p, ctx)
+#define ONE_STATE(ctx) Ppmd8Context_OneState(ctx)
+#define SUFFIX(ctx) CTX((ctx)->Suffix)
+
+#define kTop (1 << 24)
+#define kBot (1 << 15)
+
+typedef CPpmd8_Context * CTX_PTR;
+
+struct CPpmd8_Node_;
+
+typedef
+ #ifdef PPMD_32BIT
+ struct CPpmd8_Node_ *
+ #else
+ UInt32
+ #endif
+ CPpmd8_Node_Ref;
+
+typedef struct CPpmd8_Node_
+{
+ UInt32 Stamp;
+ CPpmd8_Node_Ref Next;
+ UInt32 NU;
+} CPpmd8_Node;
+
+#ifdef PPMD_32BIT
+ #define NODE(ptr) (ptr)
+#else
+ #define NODE(offs) ((CPpmd8_Node *)(p->Base + (offs)))
+#endif
+
+#define EMPTY_NODE 0xFFFFFFFF
+
+void Ppmd8_Construct(CPpmd8 *p)
+{
+ unsigned i, k, m;
+
+ p->Base = 0;
+
+ for (i = 0, k = 0; i < PPMD_NUM_INDEXES; i++)
+ {
+ unsigned step = (i >= 12 ? 4 : (i >> 2) + 1);
+ do { p->Units2Indx[k++] = (Byte)i; } while (--step);
+ p->Indx2Units[i] = (Byte)k;
+ }
+
+ p->NS2BSIndx[0] = (0 << 1);
+ p->NS2BSIndx[1] = (1 << 1);
+ memset(p->NS2BSIndx + 2, (2 << 1), 9);
+ memset(p->NS2BSIndx + 11, (3 << 1), 256 - 11);
+
+ for (i = 0; i < 5; i++)
+ p->NS2Indx[i] = (Byte)i;
+ for (m = i, k = 1; i < 260; i++)
+ {
+ p->NS2Indx[i] = (Byte)m;
+ if (--k == 0)
+ k = (++m) - 4;
+ }
+}
+
+void Ppmd8_Free(CPpmd8 *p)
+{
+ free(p->Base);
+ p->Size = 0;
+ p->Base = 0;
+}
+
+Bool Ppmd8_Alloc(CPpmd8 *p, UInt32 size)
+{
+ if (p->Base == 0 || p->Size != size)
+ {
+ Ppmd8_Free(p);
+ p->AlignOffset =
+ #ifdef PPMD_32BIT
+ (4 - size) & 3;
+ #else
+ 4 - (size & 3);
+ #endif
+ if ((p->Base = (Byte *)malloc(p->AlignOffset + size)) == 0)
+ return False;
+ p->Size = size;
+ }
+ return True;
+}
+
+static void InsertNode(CPpmd8 *p, void *node, unsigned indx)
+{
+ ((CPpmd8_Node *)node)->Stamp = EMPTY_NODE;
+ ((CPpmd8_Node *)node)->Next = (CPpmd8_Node_Ref)p->FreeList[indx];
+ ((CPpmd8_Node *)node)->NU = I2U(indx);
+ p->FreeList[indx] = REF(node);
+ p->Stamps[indx]++;
+}
+
+static void *RemoveNode(CPpmd8 *p, unsigned indx)
+{
+ CPpmd8_Node *node = NODE((CPpmd8_Node_Ref)p->FreeList[indx]);
+ p->FreeList[indx] = node->Next;
+ p->Stamps[indx]--;
+ return node;
+}
+
+static void SplitBlock(CPpmd8 *p, void *ptr, unsigned oldIndx, unsigned newIndx)
+{
+ unsigned i, nu = I2U(oldIndx) - I2U(newIndx);
+ ptr = (Byte *)ptr + U2B(I2U(newIndx));
+ if (I2U(i = U2I(nu)) != nu)
+ {
+ unsigned k = I2U(--i);
+ InsertNode(p, ((Byte *)ptr) + U2B(k), nu - k - 1);
+ }
+ InsertNode(p, ptr, i);
+}
+
+static void GlueFreeBlocks(CPpmd8 *p)
+{
+ CPpmd8_Node_Ref head = 0;
+ CPpmd8_Node_Ref *prev = &head;
+ unsigned i;
+
+ p->GlueCount = 1 << 13;
+ memset(p->Stamps, 0, sizeof(p->Stamps));
+
+ /* Order-0 context is always at top UNIT, so we don't need guard NODE at the end.
+ All blocks up to p->LoUnit can be free, so we need guard NODE at LoUnit. */
+ if (p->LoUnit != p->HiUnit)
+ ((CPpmd8_Node *)p->LoUnit)->Stamp = 0;
+
+ /* Glue free blocks */
+ for (i = 0; i < PPMD_NUM_INDEXES; i++)
+ {
+ CPpmd8_Node_Ref next = (CPpmd8_Node_Ref)p->FreeList[i];
+ p->FreeList[i] = 0;
+ while (next != 0)
+ {
+ CPpmd8_Node *node = NODE(next);
+ if (node->NU != 0)
+ {
+ CPpmd8_Node *node2;
+ *prev = next;
+ prev = &(node->Next);
+ while ((node2 = node + node->NU)->Stamp == EMPTY_NODE)
+ {
+ node->NU += node2->NU;
+ node2->NU = 0;
+ }
+ }
+ next = node->Next;
+ }
+ }
+ *prev = 0;
+
+ /* Fill lists of free blocks */
+ while (head != 0)
+ {
+ CPpmd8_Node *node = NODE(head);
+ unsigned nu;
+ head = node->Next;
+ nu = node->NU;
+ if (nu == 0)
+ continue;
+ for (; nu > 128; nu -= 128, node += 128)
+ InsertNode(p, node, PPMD_NUM_INDEXES - 1);
+ if (I2U(i = U2I(nu)) != nu)
+ {
+ unsigned k = I2U(--i);
+ InsertNode(p, node + k, nu - k - 1);
+ }
+ InsertNode(p, node, i);
+ }
+}
+
+static void *AllocUnitsRare(CPpmd8 *p, unsigned indx)
+{
+ unsigned i;
+ void *retVal;
+ if (p->GlueCount == 0)
+ {
+ GlueFreeBlocks(p);
+ if (p->FreeList[indx] != 0)
+ return RemoveNode(p, indx);
+ }
+ i = indx;
+ do
+ {
+ if (++i == PPMD_NUM_INDEXES)
+ {
+ UInt32 numBytes = U2B(I2U(indx));
+ p->GlueCount--;
+ return ((UInt32)(p->UnitsStart - p->Text) > numBytes) ? (p->UnitsStart -= numBytes) : (NULL);
+ }
+ }
+ while (p->FreeList[i] == 0);
+ retVal = RemoveNode(p, i);
+ SplitBlock(p, retVal, i, indx);
+ return retVal;
+}
+
+static void *AllocUnits(CPpmd8 *p, unsigned indx)
+{
+ UInt32 numBytes;
+ if (p->FreeList[indx] != 0)
+ return RemoveNode(p, indx);
+ numBytes = U2B(I2U(indx));
+ if (numBytes <= (UInt32)(p->HiUnit - p->LoUnit))
+ {
+ void *retVal = p->LoUnit;
+ p->LoUnit += numBytes;
+ return retVal;
+ }
+ return AllocUnitsRare(p, indx);
+}
+
+#define MyMem12Cpy(dest, src, num) \
+ { UInt32 *d = (UInt32 *)dest; const UInt32 *z = (const UInt32 *)src; UInt32 n = num; \
+ do { d[0] = z[0]; d[1] = z[1]; d[2] = z[2]; z += 3; d += 3; } while (--n); }
+
+static void *ShrinkUnits(CPpmd8 *p, void *oldPtr, unsigned oldNU, unsigned newNU)
+{
+ unsigned i0 = U2I(oldNU);
+ unsigned i1 = U2I(newNU);
+ if (i0 == i1)
+ return oldPtr;
+ if (p->FreeList[i1] != 0)
+ {
+ void *ptr = RemoveNode(p, i1);
+ MyMem12Cpy(ptr, oldPtr, newNU);
+ InsertNode(p, oldPtr, i0);
+ return ptr;
+ }
+ SplitBlock(p, oldPtr, i0, i1);
+ return oldPtr;
+}
+
+static void FreeUnits(CPpmd8 *p, void *ptr, unsigned nu)
+{
+ InsertNode(p, ptr, U2I(nu));
+}
+
+static void SpecialFreeUnit(CPpmd8 *p, void *ptr)
+{
+ if ((Byte *)ptr != p->UnitsStart)
+ InsertNode(p, ptr, 0);
+ else
+ {
+ #ifdef PPMD8_FREEZE_SUPPORT
+ *(UInt32 *)ptr = EMPTY_NODE; /* it's used for (Flags == 0xFF) check in RemoveBinContexts */
+ #endif
+ p->UnitsStart += UNIT_SIZE;
+ }
+}
+
+static void *MoveUnitsUp(CPpmd8 *p, void *oldPtr, unsigned nu)
+{
+ unsigned indx = U2I(nu);
+ void *ptr;
+ if ((Byte *)oldPtr > p->UnitsStart + 16 * 1024 || REF(oldPtr) > p->FreeList[indx])
+ return oldPtr;
+ ptr = RemoveNode(p, indx);
+ MyMem12Cpy(ptr, oldPtr, nu);
+ if ((Byte*)oldPtr != p->UnitsStart)
+ InsertNode(p, oldPtr, indx);
+ else
+ p->UnitsStart += U2B(I2U(indx));
+ return ptr;
+}
+
+static void ExpandTextArea(CPpmd8 *p)
+{
+ UInt32 count[PPMD_NUM_INDEXES];
+ unsigned i;
+ memset(count, 0, sizeof(count));
+ if (p->LoUnit != p->HiUnit)
+ ((CPpmd8_Node *)p->LoUnit)->Stamp = 0;
+
+ {
+ CPpmd8_Node *node = (CPpmd8_Node *)p->UnitsStart;
+ for (; node->Stamp == EMPTY_NODE; node += node->NU)
+ {
+ node->Stamp = 0;
+ count[U2I(node->NU)]++;
+ }
+ p->UnitsStart = (Byte *)node;
+ }
+
+ for (i = 0; i < PPMD_NUM_INDEXES; i++)
+ {
+ CPpmd8_Node_Ref *next = (CPpmd8_Node_Ref *)&p->FreeList[i];
+ while (count[i] != 0)
+ {
+ CPpmd8_Node *node = NODE(*next);
+ while (node->Stamp == 0)
+ {
+ *next = node->Next;
+ node = NODE(*next);
+ p->Stamps[i]--;
+ if (--count[i] == 0)
+ break;
+ }
+ next = &node->Next;
+ }
+ }
+}
+
+#define SUCCESSOR(p) ((CPpmd_Void_Ref)((p)->SuccessorLow | ((UInt32)(p)->SuccessorHigh << 16)))
+
+static void SetSuccessor(CPpmd_State *p, CPpmd_Void_Ref v)
+{
+ (p)->SuccessorLow = (UInt16)((UInt32)(v) & 0xFFFF);
+ (p)->SuccessorHigh = (UInt16)(((UInt32)(v) >> 16) & 0xFFFF);
+}
+
+#define RESET_TEXT(offs) { p->Text = p->Base + p->AlignOffset + (offs); }
+
+static void RestartModel(CPpmd8 *p)
+{
+ unsigned i, k, m, r;
+
+ memset(p->FreeList, 0, sizeof(p->FreeList));
+ memset(p->Stamps, 0, sizeof(p->Stamps));
+ RESET_TEXT(0);
+ p->HiUnit = p->Text + p->Size;
+ p->LoUnit = p->UnitsStart = p->HiUnit - p->Size / 8 / UNIT_SIZE * 7 * UNIT_SIZE;
+ p->GlueCount = 0;
+
+ p->OrderFall = p->MaxOrder;
+ p->RunLength = p->InitRL = -(Int32)((p->MaxOrder < 12) ? p->MaxOrder : 12) - 1;
+ p->PrevSuccess = 0;
+
+ p->MinContext = p->MaxContext = (CTX_PTR)(p->HiUnit -= UNIT_SIZE); /* AllocContext(p); */
+ p->MinContext->Suffix = 0;
+ p->MinContext->NumStats = 255;
+ p->MinContext->Flags = 0;
+ p->MinContext->SummFreq = 256 + 1;
+ p->FoundState = (CPpmd_State *)p->LoUnit; /* AllocUnits(p, PPMD_NUM_INDEXES - 1); */
+ p->LoUnit += U2B(256 / 2);
+ p->MinContext->Stats = REF(p->FoundState);
+ for (i = 0; i < 256; i++)
+ {
+ CPpmd_State *s = &p->FoundState[i];
+ s->Symbol = (Byte)i;
+ s->Freq = 1;
+ SetSuccessor(s, 0);
+ }
+
+ for (i = m = 0; m < 25; m++)
+ {
+ while (p->NS2Indx[i] == m)
+ i++;
+ for (k = 0; k < 8; k++)
+ {
+ UInt16 val = (UInt16)(PPMD_BIN_SCALE - kInitBinEsc[k] / (i + 1));
+ UInt16 *dest = p->BinSumm[m] + k;
+ for (r = 0; r < 64; r += 8)
+ dest[r] = val;
+ }
+ }
+
+ for (i = m = 0; m < 24; m++)
+ {
+ while (p->NS2Indx[i + 3] == m + 3)
+ i++;
+ for (k = 0; k < 32; k++)
+ {
+ CPpmd_See *s = &p->See[m][k];
+ s->Summ = (UInt16)((2 * i + 5) << (s->Shift = PPMD_PERIOD_BITS - 4));
+ s->Count = 7;
+ }
+ }
+}
+
+void Ppmd8_Init(CPpmd8 *p, unsigned maxOrder, unsigned restoreMethod)
+{
+ p->MaxOrder = maxOrder;
+ p->RestoreMethod = restoreMethod;
+ RestartModel(p);
+ p->DummySee.Shift = PPMD_PERIOD_BITS;
+ p->DummySee.Summ = 0; /* unused */
+ p->DummySee.Count = 64; /* unused */
+}
+
+static void Refresh(CPpmd8 *p, CTX_PTR ctx, unsigned oldNU, unsigned scale)
+{
+ unsigned i = ctx->NumStats, escFreq, sumFreq, flags;
+ CPpmd_State *s = (CPpmd_State *)ShrinkUnits(p, STATS(ctx), oldNU, (i + 2) >> 1);
+ ctx->Stats = REF(s);
+ #ifdef PPMD8_FREEZE_SUPPORT
+ /* fixed over Shkarin's code. Fixed code is not compatible with original code for some files in FREEZE mode. */
+ scale |= (ctx->SummFreq >= ((UInt32)1 << 15));
+ #endif
+ flags = (ctx->Flags & (0x10 + 0x04 * scale)) + 0x08 * (s->Symbol >= 0x40);
+ escFreq = ctx->SummFreq - s->Freq;
+ sumFreq = (s->Freq = (Byte)((s->Freq + scale) >> scale));
+ do
+ {
+ escFreq -= (++s)->Freq;
+ sumFreq += (s->Freq = (Byte)((s->Freq + scale) >> scale));
+ flags |= 0x08 * (s->Symbol >= 0x40);
+ }
+ while (--i);
+ ctx->SummFreq = (UInt16)(sumFreq + ((escFreq + scale) >> scale));
+ ctx->Flags = (Byte)flags;
+}
+
+static void SwapStates(CPpmd_State *t1, CPpmd_State *t2)
+{
+ CPpmd_State tmp = *t1;
+ *t1 = *t2;
+ *t2 = tmp;
+}
+
+static CPpmd_Void_Ref CutOff(CPpmd8 *p, CTX_PTR ctx, unsigned order)
+{
+ int i;
+ unsigned tmp;
+ CPpmd_State *s;
+
+ if (!ctx->NumStats)
+ {
+ s = ONE_STATE(ctx);
+ if ((Byte *)Ppmd8_GetPtr(p, SUCCESSOR(s)) >= p->UnitsStart)
+ {
+ if (order < p->MaxOrder)
+ SetSuccessor(s, CutOff(p, CTX(SUCCESSOR(s)), order + 1));
+ else
+ SetSuccessor(s, 0);
+ if (SUCCESSOR(s) || order <= 9) /* O_BOUND */
+ return REF(ctx);
+ }
+ SpecialFreeUnit(p, ctx);
+ return 0;
+ }
+
+ ctx->Stats = STATS_REF(MoveUnitsUp(p, STATS(ctx), tmp = ((unsigned)ctx->NumStats + 2) >> 1));
+
+ for (s = STATS(ctx) + (i = ctx->NumStats); s >= STATS(ctx); s--)
+ if ((Byte *)Ppmd8_GetPtr(p, SUCCESSOR(s)) < p->UnitsStart)
+ {
+ CPpmd_State *s2 = STATS(ctx) + (i--);
+ SetSuccessor(s, 0);
+ SwapStates(s, s2);
+ }
+ else if (order < p->MaxOrder)
+ SetSuccessor(s, CutOff(p, CTX(SUCCESSOR(s)), order + 1));
+ else
+ SetSuccessor(s, 0);
+
+ if (i != ctx->NumStats && order)
+ {
+ ctx->NumStats = (Byte)i;
+ s = STATS(ctx);
+ if (i < 0)
+ {
+ FreeUnits(p, s, tmp);
+ SpecialFreeUnit(p, ctx);
+ return 0;
+ }
+ if (i == 0)
+ {
+ ctx->Flags = (Byte)((ctx->Flags & 0x10) + 0x08 * (s->Symbol >= 0x40));
+ *ONE_STATE(ctx) = *s;
+ FreeUnits(p, s, tmp);
+ /* 9.31: the code was fixed. It's was not BUG, if Freq <= MAX_FREQ = 124 */
+ ONE_STATE(ctx)->Freq = (Byte)(((unsigned)ONE_STATE(ctx)->Freq + 11) >> 3);
+ }
+ else
+ Refresh(p, ctx, tmp, ctx->SummFreq > 16 * i);
+ }
+ return REF(ctx);
+}
+
+#ifdef PPMD8_FREEZE_SUPPORT
+static CPpmd_Void_Ref RemoveBinContexts(CPpmd8 *p, CTX_PTR ctx, unsigned order)
+{
+ CPpmd_State *s;
+ if (!ctx->NumStats)
+ {
+ s = ONE_STATE(ctx);
+ if ((Byte *)Ppmd8_GetPtr(p, SUCCESSOR(s)) >= p->UnitsStart && order < p->MaxOrder)
+ SetSuccessor(s, RemoveBinContexts(p, CTX(SUCCESSOR(s)), order + 1));
+ else
+ SetSuccessor(s, 0);
+ /* Suffix context can be removed already, since different (high-order)
+ Successors may refer to same context. So we check Flags == 0xFF (Stamp == EMPTY_NODE) */
+ if (!SUCCESSOR(s) && (!SUFFIX(ctx)->NumStats || SUFFIX(ctx)->Flags == 0xFF))
+ {
+ FreeUnits(p, ctx, 1);
+ return 0;
+ }
+ else
+ return REF(ctx);
+ }
+
+ for (s = STATS(ctx) + ctx->NumStats; s >= STATS(ctx); s--)
+ if ((Byte *)Ppmd8_GetPtr(p, SUCCESSOR(s)) >= p->UnitsStart && order < p->MaxOrder)
+ SetSuccessor(s, RemoveBinContexts(p, CTX(SUCCESSOR(s)), order + 1));
+ else
+ SetSuccessor(s, 0);
+
+ return REF(ctx);
+}
+#endif
+
+static UInt32 GetUsedMemory(const CPpmd8 *p)
+{
+ UInt32 v = 0;
+ unsigned i;
+ for (i = 0; i < PPMD_NUM_INDEXES; i++)
+ v += p->Stamps[i] * I2U(i);
+ return p->Size - (UInt32)(p->HiUnit - p->LoUnit) - (UInt32)(p->UnitsStart - p->Text) - U2B(v);
+}
+
+#ifdef PPMD8_FREEZE_SUPPORT
+ #define RESTORE_MODEL(c1, fSuccessor) RestoreModel(p, c1, fSuccessor)
+#else
+ #define RESTORE_MODEL(c1, fSuccessor) RestoreModel(p, c1)
+#endif
+
+static void RestoreModel(CPpmd8 *p, CTX_PTR c1
+ #ifdef PPMD8_FREEZE_SUPPORT
+ , CTX_PTR fSuccessor
+ #endif
+ )
+{
+ CTX_PTR c;
+ CPpmd_State *s;
+ RESET_TEXT(0);
+ for (c = p->MaxContext; c != c1; c = SUFFIX(c))
+ if (--(c->NumStats) == 0)
+ {
+ s = STATS(c);
+ c->Flags = (Byte)((c->Flags & 0x10) + 0x08 * (s->Symbol >= 0x40));
+ *ONE_STATE(c) = *s;
+ SpecialFreeUnit(p, s);
+ ONE_STATE(c)->Freq = (Byte)(((unsigned)ONE_STATE(c)->Freq + 11) >> 3);
+ }
+ else
+ Refresh(p, c, (c->NumStats+3) >> 1, 0);
+
+ for (; c != p->MinContext; c = SUFFIX(c))
+ if (!c->NumStats)
+ ONE_STATE(c)->Freq = (Byte)(ONE_STATE(c)->Freq - (ONE_STATE(c)->Freq >> 1));
+ else if ((c->SummFreq += 4) > 128 + 4 * c->NumStats)
+ Refresh(p, c, (c->NumStats + 2) >> 1, 1);
+
+ #ifdef PPMD8_FREEZE_SUPPORT
+ if (p->RestoreMethod > PPMD8_RESTORE_METHOD_FREEZE)
+ {
+ p->MaxContext = fSuccessor;
+ p->GlueCount += !(p->Stamps[1] & 1);
+ }
+ else if (p->RestoreMethod == PPMD8_RESTORE_METHOD_FREEZE)
+ {
+ while (p->MaxContext->Suffix)
+ p->MaxContext = SUFFIX(p->MaxContext);
+ RemoveBinContexts(p, p->MaxContext, 0);
+ p->RestoreMethod++;
+ p->GlueCount = 0;
+ p->OrderFall = p->MaxOrder;
+ }
+ else
+ #endif
+ if (p->RestoreMethod == PPMD8_RESTORE_METHOD_RESTART || GetUsedMemory(p) < (p->Size >> 1))
+ RestartModel(p);
+ else
+ {
+ while (p->MaxContext->Suffix)
+ p->MaxContext = SUFFIX(p->MaxContext);
+ do
+ {
+ CutOff(p, p->MaxContext, 0);
+ ExpandTextArea(p);
+ }
+ while (GetUsedMemory(p) > 3 * (p->Size >> 2));
+ p->GlueCount = 0;
+ p->OrderFall = p->MaxOrder;
+ }
+}
+
+static CTX_PTR CreateSuccessors(CPpmd8 *p, Bool skip, CPpmd_State *s1, CTX_PTR c)
+{
+ CPpmd_State upState;
+ Byte flags;
+ CPpmd_Byte_Ref upBranch = (CPpmd_Byte_Ref)SUCCESSOR(p->FoundState);
+ /* fixed over Shkarin's code. Maybe it could work without + 1 too. */
+ CPpmd_State *ps[PPMD8_MAX_ORDER + 1];
+ unsigned numPs = 0;
+
+ if (!skip)
+ ps[numPs++] = p->FoundState;
+
+ while (c->Suffix)
+ {
+ CPpmd_Void_Ref successor;
+ CPpmd_State *s;
+ c = SUFFIX(c);
+ if (s1)
+ {
+ s = s1;
+ s1 = NULL;
+ }
+ else if (c->NumStats != 0)
+ {
+ for (s = STATS(c); s->Symbol != p->FoundState->Symbol; s++);
+ if (s->Freq < MAX_FREQ - 9)
+ {
+ s->Freq++;
+ c->SummFreq++;
+ }
+ }
+ else
+ {
+ s = ONE_STATE(c);
+ s->Freq = (Byte)(s->Freq + (!SUFFIX(c)->NumStats & (s->Freq < 24)));
+ }
+ successor = SUCCESSOR(s);
+ if (successor != upBranch)
+ {
+ c = CTX(successor);
+ if (numPs == 0)
+ return c;
+ break;
+ }
+ ps[numPs++] = s;
+ }
+
+ upState.Symbol = *(const Byte *)Ppmd8_GetPtr(p, upBranch);
+ SetSuccessor(&upState, upBranch + 1);
+ flags = (Byte)(0x10 * (p->FoundState->Symbol >= 0x40) + 0x08 * (upState.Symbol >= 0x40));
+
+ if (c->NumStats == 0)
+ upState.Freq = ONE_STATE(c)->Freq;
+ else
+ {
+ UInt32 cf, s0;
+ CPpmd_State *s;
+ for (s = STATS(c); s->Symbol != upState.Symbol; s++);
+ cf = s->Freq - 1;
+ s0 = c->SummFreq - c->NumStats - cf;
+ upState.Freq = (Byte)(1 + ((2 * cf <= s0) ? (5 * cf > s0) : ((cf + 2 * s0 - 3) / s0)));
+ }
+
+ do
+ {
+ /* Create Child */
+ CTX_PTR c1; /* = AllocContext(p); */
+ if (p->HiUnit != p->LoUnit)
+ c1 = (CTX_PTR)(p->HiUnit -= UNIT_SIZE);
+ else if (p->FreeList[0] != 0)
+ c1 = (CTX_PTR)RemoveNode(p, 0);
+ else
+ {
+ c1 = (CTX_PTR)AllocUnitsRare(p, 0);
+ if (!c1)
+ return NULL;
+ }
+ c1->NumStats = 0;
+ c1->Flags = flags;
+ *ONE_STATE(c1) = upState;
+ c1->Suffix = REF(c);
+ SetSuccessor(ps[--numPs], REF(c1));
+ c = c1;
+ }
+ while (numPs != 0);
+
+ return c;
+}
+
+static CTX_PTR ReduceOrder(CPpmd8 *p, CPpmd_State *s1, CTX_PTR c)
+{
+ CPpmd_State *s = NULL;
+ CTX_PTR c1 = c;
+ CPpmd_Void_Ref upBranch = REF(p->Text);
+
+ #ifdef PPMD8_FREEZE_SUPPORT
+ /* The BUG in Shkarin's code was fixed: ps could overflow in CUT_OFF mode. */
+ CPpmd_State *ps[PPMD8_MAX_ORDER + 1];
+ unsigned numPs = 0;
+ ps[numPs++] = p->FoundState;
+ #endif
+
+ SetSuccessor(p->FoundState, upBranch);
+ p->OrderFall++;
+
+ for (;;)
+ {
+ if (s1)
+ {
+ c = SUFFIX(c);
+ s = s1;
+ s1 = NULL;
+ }
+ else
+ {
+ if (!c->Suffix)
+ {
+ #ifdef PPMD8_FREEZE_SUPPORT
+ if (p->RestoreMethod > PPMD8_RESTORE_METHOD_FREEZE)
+ {
+ do { SetSuccessor(ps[--numPs], REF(c)); } while (numPs);
+ RESET_TEXT(1);
+ p->OrderFall = 1;
+ }
+ #endif
+ return c;
+ }
+ c = SUFFIX(c);
+ if (c->NumStats)
+ {
+ if ((s = STATS(c))->Symbol != p->FoundState->Symbol)
+ do { s++; } while (s->Symbol != p->FoundState->Symbol);
+ if (s->Freq < MAX_FREQ - 9)
+ {
+ s->Freq += 2;
+ c->SummFreq += 2;
+ }
+ }
+ else
+ {
+ s = ONE_STATE(c);
+ s->Freq = (Byte)(s->Freq + (s->Freq < 32));
+ }
+ }
+ if (SUCCESSOR(s))
+ break;
+ #ifdef PPMD8_FREEZE_SUPPORT
+ ps[numPs++] = s;
+ #endif
+ SetSuccessor(s, upBranch);
+ p->OrderFall++;
+ }
+
+ #ifdef PPMD8_FREEZE_SUPPORT
+ if (p->RestoreMethod > PPMD8_RESTORE_METHOD_FREEZE)
+ {
+ c = CTX(SUCCESSOR(s));
+ do { SetSuccessor(ps[--numPs], REF(c)); } while (numPs);
+ RESET_TEXT(1);
+ p->OrderFall = 1;
+ return c;
+ }
+ else
+ #endif
+ if (SUCCESSOR(s) <= upBranch)
+ {
+ CTX_PTR successor;
+ CPpmd_State *s2 = p->FoundState;
+ p->FoundState = s;
+
+ successor = CreateSuccessors(p, False, NULL, c);
+ if (successor == NULL)
+ SetSuccessor(s, 0);
+ else
+ SetSuccessor(s, REF(successor));
+ p->FoundState = s2;
+ }
+
+ if (p->OrderFall == 1 && c1 == p->MaxContext)
+ {
+ SetSuccessor(p->FoundState, SUCCESSOR(s));
+ p->Text--;
+ }
+ if (SUCCESSOR(s) == 0)
+ return NULL;
+ return CTX(SUCCESSOR(s));
+}
+
+static void UpdateModel(CPpmd8 *p)
+{
+ CPpmd_Void_Ref successor, fSuccessor = SUCCESSOR(p->FoundState);
+ CTX_PTR c;
+ unsigned s0, ns, fFreq = p->FoundState->Freq;
+ Byte flag, fSymbol = p->FoundState->Symbol;
+ CPpmd_State *s = NULL;
+
+ if (p->FoundState->Freq < MAX_FREQ / 4 && p->MinContext->Suffix != 0)
+ {
+ c = SUFFIX(p->MinContext);
+
+ if (c->NumStats == 0)
+ {
+ s = ONE_STATE(c);
+ if (s->Freq < 32)
+ s->Freq++;
+ }
+ else
+ {
+ s = STATS(c);
+ if (s->Symbol != p->FoundState->Symbol)
+ {
+ do { s++; } while (s->Symbol != p->FoundState->Symbol);
+ if (s[0].Freq >= s[-1].Freq)
+ {
+ SwapStates(&s[0], &s[-1]);
+ s--;
+ }
+ }
+ if (s->Freq < MAX_FREQ - 9)
+ {
+ s->Freq += 2;
+ c->SummFreq += 2;
+ }
+ }
+ }
+
+ c = p->MaxContext;
+ if (p->OrderFall == 0 && fSuccessor)
+ {
+ CTX_PTR cs = CreateSuccessors(p, True, s, p->MinContext);
+ if (cs == 0)
+ {
+ SetSuccessor(p->FoundState, 0);
+ RESTORE_MODEL(c, CTX(fSuccessor));
+ }
+ else
+ {
+ SetSuccessor(p->FoundState, REF(cs));
+ p->MaxContext = cs;
+ }
+ return;
+ }
+
+ *p->Text++ = p->FoundState->Symbol;
+ successor = REF(p->Text);
+ if (p->Text >= p->UnitsStart)
+ {
+ RESTORE_MODEL(c, CTX(fSuccessor)); /* check it */
+ return;
+ }
+
+ if (!fSuccessor)
+ {
+ CTX_PTR cs = ReduceOrder(p, s, p->MinContext);
+ if (cs == NULL)
+ {
+ RESTORE_MODEL(c, 0);
+ return;
+ }
+ fSuccessor = REF(cs);
+ }
+ else if ((Byte *)Ppmd8_GetPtr(p, fSuccessor) < p->UnitsStart)
+ {
+ CTX_PTR cs = CreateSuccessors(p, False, s, p->MinContext);
+ if (cs == NULL)
+ {
+ RESTORE_MODEL(c, 0);
+ return;
+ }
+ fSuccessor = REF(cs);
+ }
+
+ if (--p->OrderFall == 0)
+ {
+ successor = fSuccessor;
+ p->Text -= (p->MaxContext != p->MinContext);
+ }
+ #ifdef PPMD8_FREEZE_SUPPORT
+ else if (p->RestoreMethod > PPMD8_RESTORE_METHOD_FREEZE)
+ {
+ successor = fSuccessor;
+ RESET_TEXT(0);
+ p->OrderFall = 0;
+ }
+ #endif
+
+ s0 = p->MinContext->SummFreq - (ns = p->MinContext->NumStats) - fFreq;
+ flag = (Byte)(0x08 * (fSymbol >= 0x40));
+
+ for (; c != p->MinContext; c = SUFFIX(c))
+ {
+ unsigned ns1;
+ UInt32 cf, sf;
+ if ((ns1 = c->NumStats) != 0)
+ {
+ if ((ns1 & 1) != 0)
+ {
+ /* Expand for one UNIT */
+ unsigned oldNU = (ns1 + 1) >> 1;
+ unsigned i = U2I(oldNU);
+ if (i != U2I(oldNU + 1))
+ {
+ void *ptr = AllocUnits(p, i + 1);
+ void *oldPtr;
+ if (!ptr)
+ {
+ RESTORE_MODEL(c, CTX(fSuccessor));
+ return;
+ }
+ oldPtr = STATS(c);
+ MyMem12Cpy(ptr, oldPtr, oldNU);
+ InsertNode(p, oldPtr, i);
+ c->Stats = STATS_REF(ptr);
+ }
+ }
+ c->SummFreq = (UInt16)(c->SummFreq + (3 * ns1 + 1 < ns));
+ }
+ else
+ {
+ CPpmd_State *s2 = (CPpmd_State*)AllocUnits(p, 0);
+ if (!s2)
+ {
+ RESTORE_MODEL(c, CTX(fSuccessor));
+ return;
+ }
+ *s2 = *ONE_STATE(c);
+ c->Stats = REF(s2);
+ if (s2->Freq < MAX_FREQ / 4 - 1)
+ s2->Freq <<= 1;
+ else
+ s2->Freq = MAX_FREQ - 4;
+ c->SummFreq = (UInt16)(s2->Freq + p->InitEsc + (ns > 2));
+ }
+ cf = 2 * fFreq * (c->SummFreq + 6);
+ sf = (UInt32)s0 + c->SummFreq;
+ if (cf < 6 * sf)
+ {
+ cf = 1 + (cf > sf) + (cf >= 4 * sf);
+ c->SummFreq += 4;
+ }
+ else
+ {
+ cf = 4 + (cf > 9 * sf) + (cf > 12 * sf) + (cf > 15 * sf);
+ c->SummFreq = (UInt16)(c->SummFreq + cf);
+ }
+ {
+ CPpmd_State *s2 = STATS(c) + ns1 + 1;
+ SetSuccessor(s2, successor);
+ s2->Symbol = fSymbol;
+ s2->Freq = (Byte)cf;
+ c->Flags |= flag;
+ c->NumStats = (Byte)(ns1 + 1);
+ }
+ }
+ p->MaxContext = p->MinContext = CTX(fSuccessor);
+}
+
+static void Rescale(CPpmd8 *p)
+{
+ unsigned i, adder, sumFreq, escFreq;
+ CPpmd_State *stats = STATS(p->MinContext);
+ CPpmd_State *s = p->FoundState;
+ {
+ CPpmd_State tmp = *s;
+ for (; s != stats; s--)
+ s[0] = s[-1];
+ *s = tmp;
+ }
+ escFreq = p->MinContext->SummFreq - s->Freq;
+ s->Freq += 4;
+ adder = (p->OrderFall != 0
+ #ifdef PPMD8_FREEZE_SUPPORT
+ || p->RestoreMethod > PPMD8_RESTORE_METHOD_FREEZE
+ #endif
+ );
+ s->Freq = (Byte)((s->Freq + adder) >> 1);
+ sumFreq = s->Freq;
+
+ i = p->MinContext->NumStats;
+ do
+ {
+ escFreq -= (++s)->Freq;
+ s->Freq = (Byte)((s->Freq + adder) >> 1);
+ sumFreq += s->Freq;
+ if (s[0].Freq > s[-1].Freq)
+ {
+ CPpmd_State *s1 = s;
+ CPpmd_State tmp = *s1;
+ do
+ s1[0] = s1[-1];
+ while (--s1 != stats && tmp.Freq > s1[-1].Freq);
+ *s1 = tmp;
+ }
+ }
+ while (--i);
+
+ if (s->Freq == 0)
+ {
+ unsigned numStats = p->MinContext->NumStats;
+ unsigned n0, n1;
+ do { i++; } while ((--s)->Freq == 0);
+ escFreq += i;
+ p->MinContext->NumStats = (Byte)(p->MinContext->NumStats - i);
+ if (p->MinContext->NumStats == 0)
+ {
+ CPpmd_State tmp = *stats;
+ tmp.Freq = (Byte)((2 * tmp.Freq + escFreq - 1) / escFreq);
+ if (tmp.Freq > MAX_FREQ / 3)
+ tmp.Freq = MAX_FREQ / 3;
+ InsertNode(p, stats, U2I((numStats + 2) >> 1));
+ p->MinContext->Flags = (Byte)((p->MinContext->Flags & 0x10) + 0x08 * (tmp.Symbol >= 0x40));
+ *(p->FoundState = ONE_STATE(p->MinContext)) = tmp;
+ return;
+ }
+ n0 = (numStats + 2) >> 1;
+ n1 = (p->MinContext->NumStats + 2) >> 1;
+ if (n0 != n1)
+ p->MinContext->Stats = STATS_REF(ShrinkUnits(p, stats, n0, n1));
+ p->MinContext->Flags &= ~0x08;
+ p->MinContext->Flags |= 0x08 * ((s = STATS(p->MinContext))->Symbol >= 0x40);
+ i = p->MinContext->NumStats;
+ do { p->MinContext->Flags |= 0x08*((++s)->Symbol >= 0x40); } while (--i);
+ }
+ p->MinContext->SummFreq = (UInt16)(sumFreq + escFreq - (escFreq >> 1));
+ p->MinContext->Flags |= 0x4;
+ p->FoundState = STATS(p->MinContext);
+}
+
+CPpmd_See *Ppmd8_MakeEscFreq(CPpmd8 *p, unsigned numMasked1, UInt32 *escFreq)
+{
+ CPpmd_See *see;
+ if (p->MinContext->NumStats != 0xFF)
+ {
+ see = p->See[(unsigned)p->NS2Indx[(unsigned)p->MinContext->NumStats + 2] - 3] +
+ (p->MinContext->SummFreq > 11 * ((unsigned)p->MinContext->NumStats + 1)) +
+ 2 * (unsigned)(2 * (unsigned)p->MinContext->NumStats <
+ ((unsigned)SUFFIX(p->MinContext)->NumStats + numMasked1)) +
+ p->MinContext->Flags;
+ {
+ unsigned r = (see->Summ >> see->Shift);
+ see->Summ = (UInt16)(see->Summ - r);
+ *escFreq = r + (r == 0);
+ }
+ }
+ else
+ {
+ see = &p->DummySee;
+ *escFreq = 1;
+ }
+ return see;
+}
+
+static void NextContext(CPpmd8 *p)
+{
+ CTX_PTR c = CTX(SUCCESSOR(p->FoundState));
+ if (p->OrderFall == 0 && (Byte *)c >= p->UnitsStart)
+ p->MinContext = p->MaxContext = c;
+ else
+ {
+ UpdateModel(p);
+ p->MinContext = p->MaxContext;
+ }
+}
+
+void Ppmd8_Update1(CPpmd8 *p)
+{
+ CPpmd_State *s = p->FoundState;
+ s->Freq += 4;
+ p->MinContext->SummFreq += 4;
+ if (s[0].Freq > s[-1].Freq)
+ {
+ SwapStates(&s[0], &s[-1]);
+ p->FoundState = --s;
+ if (s->Freq > MAX_FREQ)
+ Rescale(p);
+ }
+ NextContext(p);
+}
+
+void Ppmd8_Update1_0(CPpmd8 *p)
+{
+ p->PrevSuccess = (2 * p->FoundState->Freq >= p->MinContext->SummFreq);
+ p->RunLength += p->PrevSuccess;
+ p->MinContext->SummFreq += 4;
+ if ((p->FoundState->Freq += 4) > MAX_FREQ)
+ Rescale(p);
+ NextContext(p);
+}
+
+void Ppmd8_UpdateBin(CPpmd8 *p)
+{
+ p->FoundState->Freq = (Byte)(p->FoundState->Freq + (p->FoundState->Freq < 196));
+ p->PrevSuccess = 1;
+ p->RunLength++;
+ NextContext(p);
+}
+
+void Ppmd8_Update2(CPpmd8 *p)
+{
+ p->MinContext->SummFreq += 4;
+ if ((p->FoundState->Freq += 4) > MAX_FREQ)
+ Rescale(p);
+ p->RunLength = p->InitRL;
+ UpdateModel(p);
+ p->MinContext = p->MaxContext;
+}
+
+/* Ppmd8Dec.c -- PPMdI Decoder
+2010-04-16 : Igor Pavlov : Public domain
+This code is based on:
+ PPMd var.I (2002): Dmitry Shkarin : Public domain
+ Carryless rangecoder (1999): Dmitry Subbotin : Public domain */
+
+Bool Ppmd8_RangeDec_Init(CPpmd8 *p)
+{
+ unsigned i;
+ p->Low = 0;
+ p->Range = 0xFFFFFFFF;
+ p->Code = 0;
+ for (i = 0; i < 4; i++)
+ p->Code = (p->Code << 8) | p->Stream.In->Read(p->Stream.In);
+ return (p->Code < 0xFFFFFFFF);
+}
+
+static UInt32 RangeDec_GetThreshold(CPpmd8 *p, UInt32 total)
+{
+ return p->Code / (p->Range /= total);
+}
+
+static void RangeDec_Decode(CPpmd8 *p, UInt32 start, UInt32 size)
+{
+ start *= p->Range;
+ p->Low += start;
+ p->Code -= start;
+ p->Range *= size;
+
+ while ((p->Low ^ (p->Low + p->Range)) < kTop ||
+ (p->Range < kBot && ((p->Range = (0 - p->Low) & (kBot - 1)), 1)))
+ {
+ p->Code = (p->Code << 8) | p->Stream.In->Read(p->Stream.In);
+ p->Range <<= 8;
+ p->Low <<= 8;
+ }
+}
+
+#define MASK(sym) ((signed char *)charMask)[sym]
+
+int Ppmd8_DecodeSymbol(CPpmd8 *p)
+{
+ size_t charMask[256 / sizeof(size_t)];
+ if (p->MinContext->NumStats != 0)
+ {
+ CPpmd_State *s = Ppmd8_GetStats(p, p->MinContext);
+ unsigned i;
+ UInt32 count, hiCnt;
+ if ((count = RangeDec_GetThreshold(p, p->MinContext->SummFreq)) < (hiCnt = s->Freq))
+ {
+ Byte symbol;
+ RangeDec_Decode(p, 0, s->Freq);
+ p->FoundState = s;
+ symbol = s->Symbol;
+ Ppmd8_Update1_0(p);
+ return symbol;
+ }
+ p->PrevSuccess = 0;
+ i = p->MinContext->NumStats;
+ do
+ {
+ if ((hiCnt += (++s)->Freq) > count)
+ {
+ Byte symbol;
+ RangeDec_Decode(p, hiCnt - s->Freq, s->Freq);
+ p->FoundState = s;
+ symbol = s->Symbol;
+ Ppmd8_Update1(p);
+ return symbol;
+ }
+ }
+ while (--i);
+ if (count >= p->MinContext->SummFreq)
+ return -2;
+ RangeDec_Decode(p, hiCnt, p->MinContext->SummFreq - hiCnt);
+ PPMD_SetAllBitsIn256Bytes(charMask);
+ MASK(s->Symbol) = 0;
+ i = p->MinContext->NumStats;
+ do { MASK((--s)->Symbol) = 0; } while (--i);
+ }
+ else
+ {
+ UInt16 *prob = Ppmd8_GetBinSumm(p);
+ if (((p->Code / (p->Range >>= 14)) < *prob))
+ {
+ Byte symbol;
+ RangeDec_Decode(p, 0, *prob);
+ *prob = (UInt16)PPMD_UPDATE_PROB_0(*prob);
+ symbol = (p->FoundState = Ppmd8Context_OneState(p->MinContext))->Symbol;
+ Ppmd8_UpdateBin(p);
+ return symbol;
+ }
+ RangeDec_Decode(p, *prob, (1 << 14) - *prob);
+ *prob = (UInt16)PPMD_UPDATE_PROB_1(*prob);
+ p->InitEsc = PPMD8_kExpEscape[*prob >> 10];
+ PPMD_SetAllBitsIn256Bytes(charMask);
+ MASK(Ppmd8Context_OneState(p->MinContext)->Symbol) = 0;
+ p->PrevSuccess = 0;
+ }
+ for (;;)
+ {
+ CPpmd_State *ps[256], *s;
+ UInt32 freqSum, count, hiCnt;
+ CPpmd_See *see;
+ unsigned i, num, numMasked = p->MinContext->NumStats;
+ do
+ {
+ p->OrderFall++;
+ if (!p->MinContext->Suffix)
+ return -1;
+ p->MinContext = Ppmd8_GetContext(p, p->MinContext->Suffix);
+ }
+ while (p->MinContext->NumStats == numMasked);
+ hiCnt = 0;
+ s = Ppmd8_GetStats(p, p->MinContext);
+ i = 0;
+ num = p->MinContext->NumStats - numMasked;
+ do
+ {
+ int k = (int)(MASK(s->Symbol));
+ hiCnt += (s->Freq & k);
+ ps[i] = s++;
+ i -= k;
+ }
+ while (i != num);
+
+ see = Ppmd8_MakeEscFreq(p, numMasked, &freqSum);
+ freqSum += hiCnt;
+ count = RangeDec_GetThreshold(p, freqSum);
+
+ if (count < hiCnt)
+ {
+ Byte symbol;
+ CPpmd_State **pps = ps;
+ for (hiCnt = 0; (hiCnt += (*pps)->Freq) <= count; pps++);
+ s = *pps;
+ RangeDec_Decode(p, hiCnt - s->Freq, s->Freq);
+ Ppmd_See_Update(see);
+ p->FoundState = s;
+ symbol = s->Symbol;
+ Ppmd8_Update2(p);
+ return symbol;
+ }
+ if (count >= freqSum)
+ return -2;
+ RangeDec_Decode(p, hiCnt, freqSum - hiCnt);
+ see->Summ = (UInt16)(see->Summ + freqSum);
+ do { MASK(ps[--i]->Symbol) = 0; } while (i != 0);
+ }
+}
+
+/* H->I changes:
+ NS2Indx
+ GlewCount, and Glue method
+ BinSum
+ See / EscFreq
+ CreateSuccessors updates more suffix contexts
+ UpdateModel consts.
+ PrevSuccess Update
+*/
+
+const IPpmd8 __archive_ppmd8_functions =
+{
+ &Ppmd8_Construct,
+ &Ppmd8_Alloc,
+ &Ppmd8_Free,
+ &Ppmd8_Init,
+ &Ppmd8_RangeDec_Init,
+ &Ppmd8_DecodeSymbol,
+};