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pollymc/depends/pack200/src/coding.cpp
Petr Mrázek f56eff04ef Fix (hopefully) library dependency resolution. 
Installing libs is now enabled, hardcoded.
Enable -Wall for all builds.
Fix many warnings and latent bugs.
2013-12-01 16:34:51 +01:00

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/*
* Copyright (c) 2002, 2009, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
// -*- C++ -*-
// Small program for unpacking specially compressed Java packages.
// John R. Rose
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <assert.h>
#include <stdint.h>
#include "defines.h"
#include "bytes.h"
#include "utils.h"
#include "coding.h"
#include "constants.h"
#include "unpack.h"
extern coding basic_codings[];
#define CODING_PRIVATE(spec) \
int spec_ = spec; \
int B = CODING_B(spec_); \
int H = CODING_H(spec_); \
int L = 256 - H; \
int S = CODING_S(spec_); \
int D = CODING_D(spec_)
#define IS_NEG_CODE(S, codeVal) ((((int)(codeVal) + 1) & ((1 << S) - 1)) == 0)
#define DECODE_SIGN_S1(ux) (((uint32_t)(ux) >> 1) ^ -((int)(ux) & 1))
static int decode_sign(int S, uint32_t ux)
{ // == Coding.decodeSign32
assert(S > 0);
uint32_t sigbits = (ux >> S);
if (IS_NEG_CODE(S, ux))
return (int)(~sigbits);
else
return (int)(ux - sigbits);
// Note that (int)(ux-sigbits) can be negative, if ux is large enough.
}
coding *coding::init()
{
if (umax > 0)
return this; // already done
assert(spec != 0); // sanity
// fill in derived fields
CODING_PRIVATE(spec);
// Return nullptr if 'arb(BHSD)' parameter constraints are not met:
if (B < 1 || B > B_MAX)
return nullptr;
if (H < 1 || H > 256)
return nullptr;
if (S < 0 || S > 2)
return nullptr;
if (D < 0 || D > 1)
return nullptr;
if (B == 1 && H != 256)
return nullptr; // 1-byte coding must be fixed-size
if (B >= 5 && H == 256)
return nullptr; // no 5-byte fixed-size coding
// first compute the range of the coding, in 64 bits
int64_t range = 0;
{
int64_t H_i = 1;
for (int i = 0; i < B; i++)
{
range += H_i;
H_i *= H;
}
range *= L;
range += H_i;
}
assert(range > 0); // no useless codings, please
int this_umax;
// now, compute min and max
if (range >= ((int64_t)1 << 32))
{
this_umax = INT_MAX_VALUE;
this->umin = INT_MIN_VALUE;
this->max = INT_MAX_VALUE;
this->min = INT_MIN_VALUE;
}
else
{
this_umax = (range > INT_MAX_VALUE) ? INT_MAX_VALUE : (int)range - 1;
this->max = this_umax;
this->min = this->umin = 0;
if (S != 0 && range != 0)
{
int64_t maxPosCode = range - 1;
int64_t maxNegCode = range - 1;
while (IS_NEG_CODE(S, maxPosCode))
--maxPosCode;
while (!IS_NEG_CODE(S, maxNegCode))
--maxNegCode;
int maxPos = decode_sign(S, (uint32_t)maxPosCode);
if (maxPos < 0)
this->max = INT_MAX_VALUE; // 32-bit wraparound
else
this->max = maxPos;
if (maxNegCode < 0)
this->min = 0; // No negative codings at all.
else
this->min = decode_sign(S, (uint32_t)maxNegCode);
}
}
assert(!(isFullRange | isSigned | isSubrange)); // init
if (min < 0)
this->isSigned = true;
if (max < INT_MAX_VALUE && range <= INT_MAX_VALUE)
this->isSubrange = true;
if (max == INT_MAX_VALUE && min == INT_MIN_VALUE)
this->isFullRange = true;
// do this last, to reduce MT exposure (should have a membar too)
this->umax = this_umax;
return this;
}
coding *coding::findBySpec(int spec)
{
for (coding *scan = &basic_codings[0];; scan++)
{
if (scan->spec == spec)
return scan->init();
if (scan->spec == 0)
break;
}
coding *ptr = NEW(coding, 1);
if (!ptr)
return nullptr;
coding *c = ptr->initFrom(spec);
if (c == nullptr)
{
::free(ptr);
}
else
// else caller should free it...
c->isMalloc = true;
return c;
}
coding *coding::findBySpec(int B, int H, int S, int D)
{
if (B < 1 || B > B_MAX)
return nullptr;
if (H < 1 || H > 256)
return nullptr;
if (S < 0 || S > 2)
return nullptr;
if (D < 0 || D > 1)
return nullptr;
return findBySpec(CODING_SPEC(B, H, S, D));
}
void coding::free()
{
if (isMalloc)
{
::free(this);
}
}
void coding_method::reset(value_stream *state)
{
assert(state->rp == state->rplimit); // not in mid-stream, please
// assert(this == vs0.cm);
state[0] = vs0;
if (uValues != nullptr)
{
uValues->reset(state->helper());
}
}
uint32_t coding::parse(byte *&rp, int B, int H)
{
int L = 256 - H;
byte *ptr = rp;
// hand peel the i==0 part of the loop:
uint32_t b_i = *ptr++ & 0xFF;
if (B == 1 || b_i < (uint32_t)L)
{
rp = ptr;
return b_i;
}
uint32_t sum = b_i;
uint32_t H_i = H;
assert(B <= B_MAX);
for (int i = 2; i <= B_MAX; i++)
{ // easy for compilers to unroll if desired
b_i = *ptr++ & 0xFF;
sum += b_i * H_i;
if (i == B || b_i < (uint32_t)L)
{
rp = ptr;
return sum;
}
H_i *= H;
}
assert(false);
return 0;
}
uint32_t coding::parse_lgH(byte *&rp, int B, int H, int lgH)
{
assert(H == (1 << lgH));
int L = 256 - (1 << lgH);
byte *ptr = rp;
// hand peel the i==0 part of the loop:
uint32_t b_i = *ptr++ & 0xFF;
if (B == 1 || b_i < (uint32_t)L)
{
rp = ptr;
return b_i;
}
uint32_t sum = b_i;
uint32_t lg_H_i = lgH;
assert(B <= B_MAX);
for (int i = 2; i <= B_MAX; i++)
{ // easy for compilers to unroll if desired
b_i = *ptr++ & 0xFF;
sum += b_i << lg_H_i;
if (i == B || b_i < (uint32_t)L)
{
rp = ptr;
return sum;
}
lg_H_i += lgH;
}
assert(false);
return 0;
}
static const char ERB[] = "EOF reading band";
void coding::parseMultiple(byte *&rp, int N, byte *limit, int B, int H)
{
if (N < 0)
{
unpack_abort("bad value count");
return;
}
byte *ptr = rp;
if (B == 1 || H == 256)
{
size_t len = (size_t)N * B;
if (len / B != (size_t)N || ptr + len > limit)
{
unpack_abort(ERB);
return;
}
rp = ptr + len;
return;
}
// Note: We assume rp has enough zero-padding.
int L = 256 - H;
int n = B;
while (N > 0)
{
ptr += 1;
if (--n == 0)
{
// end of encoding at B bytes, regardless of byte value
}
else
{
int b = (ptr[-1] & 0xFF);
if (b >= L)
{
// keep going, unless we find a byte < L
continue;
}
}
// found the last byte
N -= 1;
n = B; // reset length counter
// do an error check here
if (ptr > limit)
{
unpack_abort(ERB);
return;
}
}
rp = ptr;
return;
}
bool value_stream::hasHelper()
{
// If my coding method is a pop-style method,
// then I need a second value stream to transmit
// unfavored values.
// This can be determined by examining fValues.
return cm->fValues != nullptr;
}
void value_stream::init(byte *rp_, byte *rplimit_, coding *defc)
{
rp = rp_;
rplimit = rplimit_;
sum = 0;
cm = nullptr; // no need in the simple case
setCoding(defc);
}
void value_stream::setCoding(coding *defc)
{
if (defc == nullptr)
{
unpack_abort("bad coding");
defc = coding::findByIndex(_meta_canon_min); // random pick for recovery
}
c = (*defc);
// choose cmk
cmk = cmk_ERROR;
switch (c.spec)
{
case BYTE1_spec:
cmk = cmk_BYTE1;
break;
case CHAR3_spec:
cmk = cmk_CHAR3;
break;
case UNSIGNED5_spec:
cmk = cmk_UNSIGNED5;
break;
case DELTA5_spec:
cmk = cmk_DELTA5;
break;
case BCI5_spec:
cmk = cmk_BCI5;
break;
case BRANCH5_spec:
cmk = cmk_BRANCH5;
break;
default:
if (c.D() == 0)
{
switch (c.S())
{
case 0:
cmk = cmk_BHS0;
break;
case 1:
cmk = cmk_BHS1;
break;
default:
cmk = cmk_BHS;
break;
}
}
else
{
if (c.S() == 1)
{
if (c.isFullRange)
cmk = cmk_BHS1D1full;
if (c.isSubrange)
cmk = cmk_BHS1D1sub;
}
if (cmk == cmk_ERROR)
cmk = cmk_BHSD1;
}
}
}
static int getPopValue(value_stream *self, uint32_t uval)
{
if (uval > 0)
{
// note that the initial parse performed a range check
assert(uval <= (uint32_t)self->cm->fVlength);
return self->cm->fValues[uval - 1];
}
else
{
// take an unfavored value
return self->helper()->getInt();
}
}
int coding::sumInUnsignedRange(int x, int y)
{
assert(isSubrange);
int range = (int)(umax + 1);
assert(range > 0);
x += y;
if (x != (int)((int64_t)(x - y) + (int64_t)y))
{
// 32-bit overflow interferes with range reduction.
// Back off from the overflow by adding a multiple of range:
if (x < 0)
{
x -= range;
assert(x >= 0);
}
else
{
x += range;
assert(x < 0);
}
}
if (x < 0)
{
x += range;
if (x >= 0)
return x;
}
else if (x >= range)
{
x -= range;
if (x < range)
return x;
}
else
{
// in range
return x;
}
// do it the hard way
x %= range;
if (x < 0)
x += range;
return x;
}
static int getDeltaValue(value_stream *self, uint32_t uval, bool isSubrange)
{
assert((uint32_t)(self->c.isSubrange) == (uint32_t)isSubrange);
assert(self->c.isSubrange | self->c.isFullRange);
if (isSubrange)
return self->sum = self->c.sumInUnsignedRange(self->sum, (int)uval);
else
return self->sum += (int)uval;
}
bool value_stream::hasValue()
{
if (rp < rplimit)
return true;
if (cm == nullptr)
return false;
if (cm->next == nullptr)
return false;
cm->next->reset(this);
return hasValue();
}
int value_stream::getInt()
{
if (rp >= rplimit)
{
// Advance to next coding segment.
if (rp > rplimit || cm == nullptr || cm->next == nullptr)
{
// Must perform this check and throw an exception on bad input.
unpack_abort(ERB);
return 0;
}
cm->next->reset(this);
return getInt();
}
CODING_PRIVATE(c.spec);
uint32_t uval;
enum
{
B5 = 5,
B3 = 3,
H128 = 128,
H64 = 64,
H4 = 4
};
switch (cmk)
{
case cmk_BHS:
assert(D == 0);
uval = coding::parse(rp, B, H);
if (S == 0)
return (int)uval;
return decode_sign(S, uval);
case cmk_BHS0:
assert(S == 0 && D == 0);
uval = coding::parse(rp, B, H);
return (int)uval;
case cmk_BHS1:
assert(S == 1 && D == 0);
uval = coding::parse(rp, B, H);
return DECODE_SIGN_S1(uval);
case cmk_BYTE1:
assert(c.spec == BYTE1_spec);
assert(B == 1 && H == 256 && S == 0 && D == 0);
return *rp++ & 0xFF;
case cmk_CHAR3:
assert(c.spec == CHAR3_spec);
assert(B == B3 && H == H128 && S == 0 && D == 0);
return coding::parse_lgH(rp, B3, H128, 7);
case cmk_UNSIGNED5:
assert(c.spec == UNSIGNED5_spec);
assert(B == B5 && H == H64 && S == 0 && D == 0);
return coding::parse_lgH(rp, B5, H64, 6);
case cmk_BHSD1:
assert(D == 1);
uval = coding::parse(rp, B, H);
if (S != 0)
uval = (uint32_t)decode_sign(S, uval);
return getDeltaValue(this, uval, (bool)c.isSubrange);
case cmk_BHS1D1full:
assert(S == 1 && D == 1 && c.isFullRange);
uval = coding::parse(rp, B, H);
uval = (uint32_t)DECODE_SIGN_S1(uval);
return getDeltaValue(this, uval, false);
case cmk_BHS1D1sub:
assert(S == 1 && D == 1 && c.isSubrange);
uval = coding::parse(rp, B, H);
uval = (uint32_t)DECODE_SIGN_S1(uval);
return getDeltaValue(this, uval, true);
case cmk_DELTA5:
assert(c.spec == DELTA5_spec);
assert(B == B5 && H == H64 && S == 1 && D == 1 && c.isFullRange);
uval = coding::parse_lgH(rp, B5, H64, 6);
sum += DECODE_SIGN_S1(uval);
return sum;
case cmk_BCI5:
assert(c.spec == BCI5_spec);
assert(B == B5 && H == H4 && S == 0 && D == 0);
return coding::parse_lgH(rp, B5, H4, 2);
case cmk_BRANCH5:
assert(c.spec == BRANCH5_spec);
assert(B == B5 && H == H4 && S == 2 && D == 0);
uval = coding::parse_lgH(rp, B5, H4, 2);
return decode_sign(S, uval);
case cmk_pop:
uval = coding::parse(rp, B, H);
if (S != 0)
{
uval = (uint32_t)decode_sign(S, uval);
}
if (D != 0)
{
assert(c.isSubrange | c.isFullRange);
if (c.isSubrange)
sum = c.sumInUnsignedRange(sum, (int)uval);
else
sum += (int)uval;
uval = (uint32_t)sum;
}
return getPopValue(this, uval);
case cmk_pop_BHS0:
assert(S == 0 && D == 0);
uval = coding::parse(rp, B, H);
return getPopValue(this, uval);
case cmk_pop_BYTE1:
assert(c.spec == BYTE1_spec);
assert(B == 1 && H == 256 && S == 0 && D == 0);
return getPopValue(this, *rp++ & 0xFF);
default:
break;
}
assert(false);
return 0;
}
static int moreCentral(int x, int y)
{ // used to find end of Pop.{F}
// Suggested implementation from the Pack200 specification:
uint32_t kx = (x >> 31) ^ (x << 1);
uint32_t ky = (y >> 31) ^ (y << 1);
return (kx < ky ? x : y);
}
// static maybe_inline
// int moreCentral2(int x, int y, int min) {
// // Strict implementation of buggy 150.7 specification.
// // The bug is that the spec. says absolute-value ties are broken
// // in favor of positive numbers, but the suggested implementation
// // (also mentioned in the spec.) breaks ties in favor of negative numbers.
// if ((x + y) != 0)
// return min;
// else
// // return the other value, which breaks a tie in the positive direction
// return (x > y)? x: y;
//}
static const byte *no_meta[] = {nullptr};
#define NO_META (*(byte **)no_meta)
enum
{
POP_FAVORED_N = -2
};
// mode bits
#define DISABLE_RUN 1 // used immediately inside ACodee
#define DISABLE_POP 2 // used recursively in all pop sub-bands
// This function knows all about meta-coding.
void coding_method::init(byte *&band_rp, byte *band_limit, byte *&meta_rp, int mode,
coding *defc, int N, intlist *valueSink)
{
assert(N != 0);
assert(u != nullptr); // must be pre-initialized
// if (u == nullptr) u = unpacker::current(); // expensive
int op = (meta_rp == nullptr) ? _meta_default : (*meta_rp++ & 0xFF);
coding *foundc = nullptr;
coding *to_free = nullptr;
if (op == _meta_default)
{
foundc = defc;
// and fall through
}
else if (op >= _meta_canon_min && op <= _meta_canon_max)
{
foundc = coding::findByIndex(op);
// and fall through
}
else if (op == _meta_arb)
{
int args = (*meta_rp++ & 0xFF);
// args = (D:[0..1] + 2*S[0..2] + 8*(B:[1..5]-1))
int D = ((args >> 0) & 1);
int S = ((args >> 1) & 3);
int B = ((args >> 3) & -1) + 1;
// & (H[1..256]-1)
int H = (*meta_rp++ & 0xFF) + 1;
foundc = coding::findBySpec(B, H, S, D);
to_free = foundc; // findBySpec may dynamically allocate
if (foundc == nullptr)
{
unpack_abort("illegal arbitrary coding");
return;
}
// and fall through
}
else if (op >= _meta_run && op < _meta_pop)
{
int args = (op - _meta_run);
// args: KX:[0..3] + 4*(KBFlag:[0..1]) + 8*(ABDef:[0..2])
int KX = ((args >> 0) & 3);
int KBFlag = ((args >> 2) & 1);
int ABDef = ((args >> 3) & -1);
assert(ABDef <= 2);
// & KB: one of [0..255] if KBFlag=1
int KB = (!KBFlag ? 3 : (*meta_rp++ & 0xFF));
int K = (KB + 1) << (KX * 4);
int N2 = (N >= 0) ? N - K : N;
if (N == 0 || (N2 <= 0 && N2 != N))
{
unpack_abort("illegal run encoding");
}
if ((mode & DISABLE_RUN) != 0)
{
unpack_abort("illegal nested run encoding");
}
// & Enc{ ACode } if ADef=0 (ABDef != 1)
// No direct nesting of 'run' in ACode, but in BCode it's OK.
int disRun = mode | DISABLE_RUN;
if (ABDef == 1)
{
this->init(band_rp, band_limit, NO_META, disRun, defc, K, valueSink);
}
else
{
this->init(band_rp, band_limit, meta_rp, disRun, defc, K, valueSink);
}
// & Enc{ BCode } if BDef=0 (ABDef != 2)
coding_method *tail = U_NEW(coding_method, 1);
if (!tail)
return;
tail->u = u;
// The 'run' codings may be nested indirectly via 'pop' codings.
// This means that this->next may already be filled in, if
// ACode was of type 'pop' with a 'run' token coding.
// No problem: Just chain the upcoming BCode onto the end.
for (coding_method *self = this;; self = self->next)
{
if (self->next == nullptr)
{
self->next = tail;
break;
}
}
if (ABDef == 2)
{
tail->init(band_rp, band_limit, NO_META, mode, defc, N2, valueSink);
}
else
{
tail->init(band_rp, band_limit, meta_rp, mode, defc, N2, valueSink);
}
// Note: The preceding calls to init should be tail-recursive.
return; // done; no falling through
}
else if (op >= _meta_pop && op < _meta_limit)
{
int args = (op - _meta_pop);
// args: (FDef:[0..1]) + 2*UDef:[0..1] + 4*(TDefL:[0..11])
int FDef = ((args >> 0) & 1);
int UDef = ((args >> 1) & 1);
int TDefL = ((args >> 2) & -1);
assert(TDefL <= 11);
int TDef = (TDefL > 0);
int TL = (TDefL <= 6) ? (2 << TDefL) : (256 - (4 << (11 - TDefL)));
int TH = (256 - TL);
if (N <= 0)
{
unpack_abort("illegal pop encoding");
}
if ((mode & DISABLE_POP) != 0)
{
unpack_abort("illegal nested pop encoding");
}
// No indirect nesting of 'pop', but 'run' is OK.
int disPop = DISABLE_POP;
// & Enc{ FCode } if FDef=0
int FN = POP_FAVORED_N;
assert(valueSink == nullptr);
intlist fValueSink;
fValueSink.init();
coding_method fval;
BYTES_OF(fval).clear();
fval.u = u;
if (FDef != 0)
{
fval.init(band_rp, band_limit, NO_META, disPop, defc, FN, &fValueSink);
}
else
{
fval.init(band_rp, band_limit, meta_rp, disPop, defc, FN, &fValueSink);
}
bytes fvbuf;
fValues = (u->saveTo(fvbuf, fValueSink.b), (int *)fvbuf.ptr);
fVlength = fValueSink.length(); // i.e., the parameter K
fValueSink.free();
// Skip the first {F} run in all subsequent passes.
// The next call to this->init(...) will set vs0.rp to point after the {F}.
// & Enc{ TCode } if TDef=0 (TDefL==0)
if (TDef != 0)
{
coding *tcode = coding::findBySpec(1, 256); // BYTE1
// find the most narrowly sufficient code:
for (int B = 2; B <= B_MAX; B++)
{
if (fVlength <= tcode->umax)
break; // found it
tcode->free();
tcode = coding::findBySpec(B, TH);
if (!tcode)
return;
}
if (!(fVlength <= tcode->umax))
{
unpack_abort("pop.L value too small");
}
this->init(band_rp, band_limit, NO_META, disPop, tcode, N, nullptr);
tcode->free();
}
else
{
this->init(band_rp, band_limit, meta_rp, disPop, defc, N, nullptr);
}
// Count the number of zero tokens right now.
// Also verify that they are in bounds.
int UN = 0; // one {U} for each zero in {T}
value_stream vs = vs0;
for (int i = 0; i < N; i++)
{
uint32_t val = vs.getInt();
if (val == 0)
UN += 1;
if (!(val <= (uint32_t)fVlength))
{
unpack_abort("pop token out of range");
}
}
vs.done();
// & Enc{ UCode } if UDef=0
if (UN != 0)
{
uValues = U_NEW(coding_method, 1);
if (uValues == nullptr)
return;
uValues->u = u;
if (UDef != 0)
{
uValues->init(band_rp, band_limit, NO_META, disPop, defc, UN, nullptr);
}
else
{
uValues->init(band_rp, band_limit, meta_rp, disPop, defc, UN, nullptr);
}
}
else
{
if (UDef == 0)
{
int uop = (*meta_rp++ & 0xFF);
if (uop > _meta_canon_max)
// %%% Spec. requires the more strict (uop != _meta_default).
unpack_abort("bad meta-coding for empty pop/U");
}
}
// Bug fix for 6259542
// Last of all, adjust vs0.cmk to the 'pop' flavor
for (coding_method *self = this; self != nullptr; self = self->next)
{
coding_method_kind cmk2 = cmk_pop;
switch (self->vs0.cmk)
{
case cmk_BHS0:
cmk2 = cmk_pop_BHS0;
break;
case cmk_BYTE1:
cmk2 = cmk_pop_BYTE1;
break;
default:
break;
}
self->vs0.cmk = cmk2;
if (self != this)
{
assert(self->fValues == nullptr); // no double init
self->fValues = this->fValues;
self->fVlength = this->fVlength;
assert(self->uValues == nullptr); // must stay nullptr
}
}
return; // done; no falling through
}
else
{
unpack_abort("bad meta-coding");
}
// Common code here skips a series of values with one coding.
assert(foundc != nullptr);
assert(vs0.cmk == cmk_ERROR); // no garbage, please
assert(vs0.rp == nullptr); // no garbage, please
assert(vs0.rplimit == nullptr); // no garbage, please
assert(vs0.sum == 0); // no garbage, please
vs0.init(band_rp, band_limit, foundc);
// Done with foundc. Free if necessary.
if (to_free != nullptr)
{
to_free->free();
to_free = nullptr;
}
foundc = nullptr;
coding &c = vs0.c;
CODING_PRIVATE(c.spec);
// assert sane N
assert((uint32_t)N < INT_MAX_VALUE || N == POP_FAVORED_N);
// Look at the values, or at least skip over them quickly.
if (valueSink == nullptr)
{
// Skip and ignore values in the first pass.
c.parseMultiple(band_rp, N, band_limit, B, H);
}
else if (N >= 0)
{
// Pop coding, {F} sequence, initial run of values...
assert((mode & DISABLE_POP) != 0);
value_stream vs = vs0;
for (int n = 0; n < N; n++)
{
int val = vs.getInt();
valueSink->add(val);
}
band_rp = vs.rp;
}
else
{
// Pop coding, {F} sequence, final run of values...
assert((mode & DISABLE_POP) != 0);
assert(N == POP_FAVORED_N);
int min = INT_MIN_VALUE; // farthest from the center
// min2 is based on the buggy specification of centrality in version 150.7
// no known implementations transmit this value, but just in case...
// int min2 = INT_MIN_VALUE;
int last = 0;
// if there were initial runs, find the potential sentinels in them:
for (int i = 0; i < valueSink->length(); i++)
{
last = valueSink->get(i);
min = moreCentral(min, last);
// min2 = moreCentral2(min2, last, min);
}
value_stream vs = vs0;
for (;;)
{
int val = vs.getInt();
if (valueSink->length() > 0 && (val == last || val == min)) //|| val == min2
break;
valueSink->add(val);
last = val;
min = moreCentral(min, last);
// min2 = moreCentral2(min2, last, min);
}
band_rp = vs.rp;
}
// Get an accurate upper limit now.
vs0.rplimit = band_rp;
vs0.cm = this;
return; // success
}
coding basic_codings[] = {
// This one is not a usable irregular coding, but is used by cp_Utf8_chars.
CODING_INIT(3, 128, 0, 0),
// Fixed-length codings:
CODING_INIT(1, 256, 0, 0), CODING_INIT(1, 256, 1, 0), CODING_INIT(1, 256, 0, 1),
CODING_INIT(1, 256, 1, 1), CODING_INIT(2, 256, 0, 0), CODING_INIT(2, 256, 1, 0),
CODING_INIT(2, 256, 0, 1), CODING_INIT(2, 256, 1, 1), CODING_INIT(3, 256, 0, 0),
CODING_INIT(3, 256, 1, 0), CODING_INIT(3, 256, 0, 1), CODING_INIT(3, 256, 1, 1),
CODING_INIT(4, 256, 0, 0), CODING_INIT(4, 256, 1, 0), CODING_INIT(4, 256, 0, 1),
CODING_INIT(4, 256, 1, 1),
// Full-range variable-length codings:
CODING_INIT(5, 4, 0, 0), CODING_INIT(5, 4, 1, 0), CODING_INIT(5, 4, 2, 0),
CODING_INIT(5, 16, 0, 0), CODING_INIT(5, 16, 1, 0), CODING_INIT(5, 16, 2, 0),
CODING_INIT(5, 32, 0, 0), CODING_INIT(5, 32, 1, 0), CODING_INIT(5, 32, 2, 0),
CODING_INIT(5, 64, 0, 0), CODING_INIT(5, 64, 1, 0), CODING_INIT(5, 64, 2, 0),
CODING_INIT(5, 128, 0, 0), CODING_INIT(5, 128, 1, 0), CODING_INIT(5, 128, 2, 0),
CODING_INIT(5, 4, 0, 1), CODING_INIT(5, 4, 1, 1), CODING_INIT(5, 4, 2, 1),
CODING_INIT(5, 16, 0, 1), CODING_INIT(5, 16, 1, 1), CODING_INIT(5, 16, 2, 1),
CODING_INIT(5, 32, 0, 1), CODING_INIT(5, 32, 1, 1), CODING_INIT(5, 32, 2, 1),
CODING_INIT(5, 64, 0, 1), CODING_INIT(5, 64, 1, 1), CODING_INIT(5, 64, 2, 1),
CODING_INIT(5, 128, 0, 1), CODING_INIT(5, 128, 1, 1), CODING_INIT(5, 128, 2, 1),
// Variable length subrange codings:
CODING_INIT(2, 192, 0, 0), CODING_INIT(2, 224, 0, 0), CODING_INIT(2, 240, 0, 0),
CODING_INIT(2, 248, 0, 0), CODING_INIT(2, 252, 0, 0), CODING_INIT(2, 8, 0, 1),
CODING_INIT(2, 8, 1, 1), CODING_INIT(2, 16, 0, 1), CODING_INIT(2, 16, 1, 1),
CODING_INIT(2, 32, 0, 1), CODING_INIT(2, 32, 1, 1), CODING_INIT(2, 64, 0, 1),
CODING_INIT(2, 64, 1, 1), CODING_INIT(2, 128, 0, 1), CODING_INIT(2, 128, 1, 1),
CODING_INIT(2, 192, 0, 1), CODING_INIT(2, 192, 1, 1), CODING_INIT(2, 224, 0, 1),
CODING_INIT(2, 224, 1, 1), CODING_INIT(2, 240, 0, 1), CODING_INIT(2, 240, 1, 1),
CODING_INIT(2, 248, 0, 1), CODING_INIT(2, 248, 1, 1), CODING_INIT(3, 192, 0, 0),
CODING_INIT(3, 224, 0, 0), CODING_INIT(3, 240, 0, 0), CODING_INIT(3, 248, 0, 0),
CODING_INIT(3, 252, 0, 0), CODING_INIT(3, 8, 0, 1), CODING_INIT(3, 8, 1, 1),
CODING_INIT(3, 16, 0, 1), CODING_INIT(3, 16, 1, 1), CODING_INIT(3, 32, 0, 1),
CODING_INIT(3, 32, 1, 1), CODING_INIT(3, 64, 0, 1), CODING_INIT(3, 64, 1, 1),
CODING_INIT(3, 128, 0, 1), CODING_INIT(3, 128, 1, 1), CODING_INIT(3, 192, 0, 1),
CODING_INIT(3, 192, 1, 1), CODING_INIT(3, 224, 0, 1), CODING_INIT(3, 224, 1, 1),
CODING_INIT(3, 240, 0, 1), CODING_INIT(3, 240, 1, 1), CODING_INIT(3, 248, 0, 1),
CODING_INIT(3, 248, 1, 1), CODING_INIT(4, 192, 0, 0), CODING_INIT(4, 224, 0, 0),
CODING_INIT(4, 240, 0, 0), CODING_INIT(4, 248, 0, 0), CODING_INIT(4, 252, 0, 0),
CODING_INIT(4, 8, 0, 1), CODING_INIT(4, 8, 1, 1), CODING_INIT(4, 16, 0, 1),
CODING_INIT(4, 16, 1, 1), CODING_INIT(4, 32, 0, 1), CODING_INIT(4, 32, 1, 1),
CODING_INIT(4, 64, 0, 1), CODING_INIT(4, 64, 1, 1), CODING_INIT(4, 128, 0, 1),
CODING_INIT(4, 128, 1, 1), CODING_INIT(4, 192, 0, 1), CODING_INIT(4, 192, 1, 1),
CODING_INIT(4, 224, 0, 1), CODING_INIT(4, 224, 1, 1), CODING_INIT(4, 240, 0, 1),
CODING_INIT(4, 240, 1, 1), CODING_INIT(4, 248, 0, 1), CODING_INIT(4, 248, 1, 1),
CODING_INIT(0, 0, 0, 0)};
#define BASIC_INDEX_LIMIT (int)(sizeof(basic_codings) / sizeof(basic_codings[0]) - 1)
coding *coding::findByIndex(int idx)
{
int index_limit = BASIC_INDEX_LIMIT;
assert(_meta_canon_min == 1 && _meta_canon_max + 1 == index_limit);
if (idx >= _meta_canon_min && idx <= _meta_canon_max)
return basic_codings[idx].init();
else
return nullptr;
}
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