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ghcup-hs/3rdparty/libarchive/c/archive_ppmd8.c

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Use libarchive instead of tar-bytestring
2020-07-04 21:33:48 +00:00
/* 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,
};
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