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bzip2/decompress.c
Micah Snyder 7b44372099 Project version 1.1.0, libtool version 1:9:0 
Increase the project version to 1.1.0 as this is a new feature version.

As for all new feature versions, increase the libtool .so version.
Only increase the revision, as no API's were added or removed.
It may look like I've increased it by 2, but that's because v1.0.8 used
Makefiles and was at 1:8:0.

See http://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
2022-01-30 11:50:37 -08:00

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/*-------------------------------------------------------------*/
/*--- Decompression machinery ---*/
/*--- decompress.c ---*/
/*-------------------------------------------------------------*/
/* ------------------------------------------------------------------
This file is part of bzip2/libbzip2, a program and library for
lossless, block-sorting data compression.
bzip2/libbzip2 version 1.1.0 of 6 September 2010
Copyright (C) 1996-2010 Julian Seward <jseward@acm.org>
Please read the WARNING, DISCLAIMER and PATENTS sections in the
README file.
This program is released under the terms of the license contained
in the file LICENSE.
------------------------------------------------------------------ */
#include "bzlib_private.h"
/*---------------------------------------------------*/
static
void makeMaps_d ( DState* s )
{
Int32 i;
s->nInUse = 0;
for (i = 0; i < 256; i++)
if (s->inUse[i]) {
s->seqToUnseq[s->nInUse] = i;
s->nInUse++;
}
}
/*---------------------------------------------------*/
#define RETURN(rrr) \
{ retVal = rrr; goto save_state_and_return; };
#define GET_BITS(lll,vvv,nnn) \
case lll: s->state = lll; \
while (True) { \
if (s->bsLive >= nnn) { \
UInt32 v; \
v = (s->bsBuff >> \
(s->bsLive-nnn)) & ((1 << nnn)-1); \
s->bsLive -= nnn; \
vvv = v; \
break; \
} \
if (s->strm->avail_in == 0) RETURN(BZ_OK); \
s->bsBuff \
= (s->bsBuff << 8) | \
((UInt32) \
(*((UChar*)(s->strm->next_in)))); \
s->bsLive += 8; \
s->strm->next_in++; \
s->strm->avail_in--; \
s->strm->total_in_lo32++; \
if (s->strm->total_in_lo32 == 0) \
s->strm->total_in_hi32++; \
}
#define GET_UCHAR(lll,uuu) \
GET_BITS(lll,uuu,8)
#define GET_BIT(lll,uuu) \
GET_BITS(lll,uuu,1)
/*---------------------------------------------------*/
#define GET_MTF_VAL(label1,label2,lval) \
{ \
if (groupPos == 0) { \
groupNo++; \
if (groupNo >= nSelectors) \
RETURN(BZ_DATA_ERROR); \
groupPos = BZ_G_SIZE; \
gSel = s->selector[groupNo]; \
gMinlen = s->minLens[gSel]; \
gLimit = &(s->limit[gSel][0]); \
gPerm = &(s->perm[gSel][0]); \
gBase = &(s->base[gSel][0]); \
} \
groupPos--; \
zn = gMinlen; \
GET_BITS(label1, zvec, zn); \
while (1) { \
if (zn > 20 /* the longest code */) \
RETURN(BZ_DATA_ERROR); \
if (zvec <= gLimit[zn]) break; \
zn++; \
GET_BIT(label2, zj); \
zvec = (zvec << 1) | zj; \
}; \
if (zvec - gBase[zn] < 0 \
|| zvec - gBase[zn] >= BZ_MAX_ALPHA_SIZE) \
RETURN(BZ_DATA_ERROR); \
lval = gPerm[zvec - gBase[zn]]; \
}
/*---------------------------------------------------*/
Int32 BZ2_decompress ( DState* s )
{
UChar uc;
Int32 retVal;
Int32 minLen, maxLen;
bz_stream* strm = s->strm;
/* stuff that needs to be saved/restored */
Int32 i;
Int32 j;
Int32 t;
Int32 alphaSize;
Int32 nGroups;
Int32 nSelectors;
Int32 EOB;
Int32 groupNo;
Int32 groupPos;
Int32 nextSym;
Int32 nblockMAX;
Int32 nblock;
Int32 es;
Int32 N;
Int32 curr;
Int32 zt;
Int32 zn;
Int32 zvec;
Int32 zj;
Int32 gSel;
Int32 gMinlen;
Int32* gLimit;
Int32* gBase;
Int32* gPerm;
if (s->state == BZ_X_MAGIC_1) {
/*initialise the save area*/
s->save_i = 0;
s->save_j = 0;
s->save_t = 0;
s->save_alphaSize = 0;
s->save_nGroups = 0;
s->save_nSelectors = 0;
s->save_EOB = 0;
s->save_groupNo = 0;
s->save_groupPos = 0;
s->save_nextSym = 0;
s->save_nblockMAX = 0;
s->save_nblock = 0;
s->save_es = 0;
s->save_N = 0;
s->save_curr = 0;
s->save_zt = 0;
s->save_zn = 0;
s->save_zvec = 0;
s->save_zj = 0;
s->save_gSel = 0;
s->save_gMinlen = 0;
s->save_gLimit = NULL;
s->save_gBase = NULL;
s->save_gPerm = NULL;
}
/*restore from the save area*/
i = s->save_i;
j = s->save_j;
t = s->save_t;
alphaSize = s->save_alphaSize;
nGroups = s->save_nGroups;
nSelectors = s->save_nSelectors;
EOB = s->save_EOB;
groupNo = s->save_groupNo;
groupPos = s->save_groupPos;
nextSym = s->save_nextSym;
nblockMAX = s->save_nblockMAX;
nblock = s->save_nblock;
es = s->save_es;
N = s->save_N;
curr = s->save_curr;
zt = s->save_zt;
zn = s->save_zn;
zvec = s->save_zvec;
zj = s->save_zj;
gSel = s->save_gSel;
gMinlen = s->save_gMinlen;
gLimit = s->save_gLimit;
gBase = s->save_gBase;
gPerm = s->save_gPerm;
retVal = BZ_OK;
switch (s->state) {
GET_UCHAR(BZ_X_MAGIC_1, uc);
if (uc != BZ_HDR_B) RETURN(BZ_DATA_ERROR_MAGIC);
GET_UCHAR(BZ_X_MAGIC_2, uc);
if (uc != BZ_HDR_Z) RETURN(BZ_DATA_ERROR_MAGIC);
GET_UCHAR(BZ_X_MAGIC_3, uc)
if (uc != BZ_HDR_h) RETURN(BZ_DATA_ERROR_MAGIC);
GET_BITS(BZ_X_MAGIC_4, s->blockSize100k, 8)
if (s->blockSize100k < (BZ_HDR_0 + 1) ||
s->blockSize100k > (BZ_HDR_0 + 9)) RETURN(BZ_DATA_ERROR_MAGIC);
s->blockSize100k -= BZ_HDR_0;
if (s->smallDecompress) {
s->ll16 = BZALLOC( s->blockSize100k * 100000 * sizeof(UInt16) );
s->ll4 = BZALLOC(
((1 + s->blockSize100k * 100000) >> 1) * sizeof(UChar)
);
if (s->ll16 == NULL || s->ll4 == NULL) RETURN(BZ_MEM_ERROR);
} else {
s->tt = BZALLOC( s->blockSize100k * 100000 * sizeof(Int32) );
if (s->tt == NULL) RETURN(BZ_MEM_ERROR);
}
GET_UCHAR(BZ_X_BLKHDR_1, uc);
if (uc == 0x17) goto endhdr_2;
if (uc != 0x31) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_BLKHDR_2, uc);
if (uc != 0x41) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_BLKHDR_3, uc);
if (uc != 0x59) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_BLKHDR_4, uc);
if (uc != 0x26) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_BLKHDR_5, uc);
if (uc != 0x53) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_BLKHDR_6, uc);
if (uc != 0x59) RETURN(BZ_DATA_ERROR);
s->currBlockNo++;
if (s->verbosity >= 2)
VPrintf1 ( "\n [%d: huff+mtf ", s->currBlockNo );
s->storedBlockCRC = 0;
GET_UCHAR(BZ_X_BCRC_1, uc);
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_BCRC_2, uc);
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_BCRC_3, uc);
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_BCRC_4, uc);
s->storedBlockCRC = (s->storedBlockCRC << 8) | ((UInt32)uc);
GET_BITS(BZ_X_RANDBIT, s->blockRandomised, 1);
s->origPtr = 0;
GET_UCHAR(BZ_X_ORIGPTR_1, uc);
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
GET_UCHAR(BZ_X_ORIGPTR_2, uc);
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
GET_UCHAR(BZ_X_ORIGPTR_3, uc);
s->origPtr = (s->origPtr << 8) | ((Int32)uc);
if (s->origPtr < 0)
RETURN(BZ_DATA_ERROR);
if (s->origPtr > 10 + 100000*s->blockSize100k)
RETURN(BZ_DATA_ERROR);
/*--- Receive the mapping table ---*/
for (i = 0; i < 16; i++) {
GET_BIT(BZ_X_MAPPING_1, uc);
if (uc == 1)
s->inUse16[i] = True; else
s->inUse16[i] = False;
}
for (i = 0; i < 256; i++) s->inUse[i] = False;
for (i = 0; i < 16; i++)
if (s->inUse16[i])
for (j = 0; j < 16; j++) {
GET_BIT(BZ_X_MAPPING_2, uc);
if (uc == 1) s->inUse[i * 16 + j] = True;
}
makeMaps_d ( s );
if (s->nInUse == 0) RETURN(BZ_DATA_ERROR);
alphaSize = s->nInUse+2;
/*--- Now the selectors ---*/
GET_BITS(BZ_X_SELECTOR_1, nGroups, 3);
if (nGroups < 2 || nGroups > BZ_N_GROUPS) RETURN(BZ_DATA_ERROR);
GET_BITS(BZ_X_SELECTOR_2, nSelectors, 15);
if (nSelectors < 1) RETURN(BZ_DATA_ERROR);
for (i = 0; i < nSelectors; i++) {
j = 0;
while (True) {
GET_BIT(BZ_X_SELECTOR_3, uc);
if (uc == 0) break;
j++;
if (j >= nGroups) RETURN(BZ_DATA_ERROR);
}
/* Having more than BZ_MAX_SELECTORS doesn't make much sense
since they will never be used, but some implementations might
"round up" the number of selectors, so just ignore those. */
if (i < BZ_MAX_SELECTORS)
s->selectorMtf[i] = j;
}
if (nSelectors > BZ_MAX_SELECTORS)
nSelectors = BZ_MAX_SELECTORS;
/*--- Undo the MTF values for the selectors. ---*/
{
UChar pos[BZ_N_GROUPS], tmp, v;
for (v = 0; v < nGroups; v++) pos[v] = v;
for (i = 0; i < nSelectors; i++) {
v = s->selectorMtf[i];
tmp = pos[v];
while (v > 0) { pos[v] = pos[v-1]; v--; }
pos[0] = tmp;
s->selector[i] = tmp;
}
}
/*--- Now the coding tables ---*/
for (t = 0; t < nGroups; t++) {
GET_BITS(BZ_X_CODING_1, curr, 5);
for (i = 0; i < alphaSize; i++) {
while (True) {
if (curr < 1 || curr > 20) RETURN(BZ_DATA_ERROR);
GET_BIT(BZ_X_CODING_2, uc);
if (uc == 0) break;
GET_BIT(BZ_X_CODING_3, uc);
if (uc == 0) curr++; else curr--;
}
s->len[t][i] = curr;
}
}
/*--- Create the Huffman decoding tables ---*/
for (t = 0; t < nGroups; t++) {
minLen = 32;
maxLen = 0;
for (i = 0; i < alphaSize; i++) {
if (s->len[t][i] > maxLen) maxLen = s->len[t][i];
if (s->len[t][i] < minLen) minLen = s->len[t][i];
}
BZ2_hbCreateDecodeTables (
&(s->limit[t][0]),
&(s->base[t][0]),
&(s->perm[t][0]),
&(s->len[t][0]),
minLen, maxLen, alphaSize
);
s->minLens[t] = minLen;
}
/*--- Now the MTF values ---*/
EOB = s->nInUse+1;
nblockMAX = 100000 * s->blockSize100k;
groupNo = -1;
groupPos = 0;
for (i = 0; i <= 255; i++) s->unzftab[i] = 0;
/*-- MTF init --*/
{
Int32 ii, jj, kk;
kk = MTFA_SIZE-1;
for (ii = 256 / MTFL_SIZE - 1; ii >= 0; ii--) {
for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
s->mtfa[kk] = (UChar)(ii * MTFL_SIZE + jj);
kk--;
}
s->mtfbase[ii] = kk + 1;
}
}
/*-- end MTF init --*/
nblock = 0;
GET_MTF_VAL(BZ_X_MTF_1, BZ_X_MTF_2, nextSym);
while (True) {
if (nextSym == EOB) break;
if (nextSym == BZ_RUNA || nextSym == BZ_RUNB) {
es = -1;
N = 1;
do {
/* Check that N doesn't get too big, so that es doesn't
go negative. The maximum value that can be
RUNA/RUNB encoded is equal to the block size (post
the initial RLE), viz, 900k, so bounding N at 2
million should guard against overflow without
rejecting any legitimate inputs. */
if (N >= 2*1024*1024) RETURN(BZ_DATA_ERROR);
if (nextSym == BZ_RUNA) es = es + (0+1) * N; else
if (nextSym == BZ_RUNB) es = es + (1+1) * N;
N = N * 2;
GET_MTF_VAL(BZ_X_MTF_3, BZ_X_MTF_4, nextSym);
}
while (nextSym == BZ_RUNA || nextSym == BZ_RUNB);
es++;
uc = s->seqToUnseq[ s->mtfa[s->mtfbase[0]] ];
s->unzftab[uc] += es;
if (s->smallDecompress)
while (es > 0) {
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
s->ll16[nblock] = (UInt16)uc;
nblock++;
es--;
}
else
while (es > 0) {
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
s->tt[nblock] = (UInt32)uc;
nblock++;
es--;
};
continue;
} else {
if (nblock >= nblockMAX) RETURN(BZ_DATA_ERROR);
/*-- uc = MTF ( nextSym-1 ) --*/
{
Int32 ii, jj, kk, pp, lno, off;
UInt32 nn;
nn = (UInt32)(nextSym - 1);
if (nn < MTFL_SIZE) {
/* avoid general-case expense */
pp = s->mtfbase[0];
uc = s->mtfa[pp+nn];
while (nn > 3) {
Int32 z = pp+nn;
s->mtfa[(z) ] = s->mtfa[(z)-1];
s->mtfa[(z)-1] = s->mtfa[(z)-2];
s->mtfa[(z)-2] = s->mtfa[(z)-3];
s->mtfa[(z)-3] = s->mtfa[(z)-4];
nn -= 4;
}
while (nn > 0) {
s->mtfa[(pp+nn)] = s->mtfa[(pp+nn)-1]; nn--;
};
s->mtfa[pp] = uc;
} else {
/* general case */
lno = nn / MTFL_SIZE;
off = nn % MTFL_SIZE;
pp = s->mtfbase[lno] + off;
uc = s->mtfa[pp];
while (pp > s->mtfbase[lno]) {
s->mtfa[pp] = s->mtfa[pp-1]; pp--;
};
s->mtfbase[lno]++;
while (lno > 0) {
s->mtfbase[lno]--;
s->mtfa[s->mtfbase[lno]]
= s->mtfa[s->mtfbase[lno-1] + MTFL_SIZE - 1];
lno--;
}
s->mtfbase[0]--;
s->mtfa[s->mtfbase[0]] = uc;
if (s->mtfbase[0] == 0) {
kk = MTFA_SIZE-1;
for (ii = 256 / MTFL_SIZE-1; ii >= 0; ii--) {
for (jj = MTFL_SIZE-1; jj >= 0; jj--) {
s->mtfa[kk] = s->mtfa[s->mtfbase[ii] + jj];
kk--;
}
s->mtfbase[ii] = kk + 1;
}
}
}
}
/*-- end uc = MTF ( nextSym-1 ) --*/
s->unzftab[s->seqToUnseq[uc]]++;
if (s->smallDecompress)
s->ll16[nblock] = (UInt16)(s->seqToUnseq[uc]); else
s->tt[nblock] = (UInt32)(s->seqToUnseq[uc]);
nblock++;
GET_MTF_VAL(BZ_X_MTF_5, BZ_X_MTF_6, nextSym);
continue;
}
}
/* Now we know what nblock is, we can do a better sanity
check on s->origPtr.
*/
if (s->origPtr < 0 || s->origPtr >= nblock)
RETURN(BZ_DATA_ERROR);
/*-- Set up cftab to facilitate generation of T^(-1) --*/
/* Check: unzftab entries in range. */
for (i = 0; i <= 255; i++) {
if (s->unzftab[i] < 0 || s->unzftab[i] > nblock)
RETURN(BZ_DATA_ERROR);
}
/* Actually generate cftab. */
s->cftab[0] = 0;
for (i = 1; i <= 256; i++) s->cftab[i] = s->unzftab[i-1];
for (i = 1; i <= 256; i++) s->cftab[i] += s->cftab[i-1];
/* Check: cftab entries in range. */
for (i = 0; i <= 256; i++) {
if (s->cftab[i] < 0 || s->cftab[i] > nblock) {
/* s->cftab[i] can legitimately be == nblock */
RETURN(BZ_DATA_ERROR);
}
}
/* Check: cftab entries non-descending. */
for (i = 1; i <= 256; i++) {
if (s->cftab[i-1] > s->cftab[i]) {
RETURN(BZ_DATA_ERROR);
}
}
s->state_out_len = 0;
s->state_out_ch = 0;
BZ_INITIALISE_CRC ( s->calculatedBlockCRC );
s->state = BZ_X_OUTPUT;
if (s->verbosity >= 2) VPrintf0 ( "rt+rld" );
if (s->smallDecompress) {
/*-- Make a copy of cftab, used in generation of T --*/
for (i = 0; i <= 256; i++) s->cftabCopy[i] = s->cftab[i];
/*-- compute the T vector --*/
for (i = 0; i < nblock; i++) {
uc = (UChar)(s->ll16[i]);
SET_LL(i, s->cftabCopy[uc]);
s->cftabCopy[uc]++;
}
/*-- Compute T^(-1) by pointer reversal on T --*/
i = s->origPtr;
j = GET_LL(i);
do {
Int32 tmp = GET_LL(j);
SET_LL(j, i);
i = j;
j = tmp;
}
while (i != s->origPtr);
s->tPos = s->origPtr;
s->nblock_used = 0;
if (s->blockRandomised) {
BZ_RAND_INIT_MASK;
BZ_GET_SMALL(s->k0); s->nblock_used++;
BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
} else {
BZ_GET_SMALL(s->k0); s->nblock_used++;
}
} else {
/*-- compute the T^(-1) vector --*/
for (i = 0; i < nblock; i++) {
uc = (UChar)(s->tt[i] & 0xff);
s->tt[s->cftab[uc]] |= (i << 8);
s->cftab[uc]++;
}
s->tPos = s->tt[s->origPtr] >> 8;
s->nblock_used = 0;
if (s->blockRandomised) {
BZ_RAND_INIT_MASK;
BZ_GET_FAST(s->k0); s->nblock_used++;
BZ_RAND_UPD_MASK; s->k0 ^= BZ_RAND_MASK;
} else {
BZ_GET_FAST(s->k0); s->nblock_used++;
}
}
RETURN(BZ_OK);
endhdr_2:
GET_UCHAR(BZ_X_ENDHDR_2, uc);
if (uc != 0x72) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_ENDHDR_3, uc);
if (uc != 0x45) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_ENDHDR_4, uc);
if (uc != 0x38) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_ENDHDR_5, uc);
if (uc != 0x50) RETURN(BZ_DATA_ERROR);
GET_UCHAR(BZ_X_ENDHDR_6, uc);
if (uc != 0x90) RETURN(BZ_DATA_ERROR);
s->storedCombinedCRC = 0;
GET_UCHAR(BZ_X_CCRC_1, uc);
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_CCRC_2, uc);
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_CCRC_3, uc);
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
GET_UCHAR(BZ_X_CCRC_4, uc);
s->storedCombinedCRC = (s->storedCombinedCRC << 8) | ((UInt32)uc);
s->state = BZ_X_IDLE;
RETURN(BZ_STREAM_END);
default: AssertH ( False, 4001 );
}
AssertH ( False, 4002 );
save_state_and_return:
s->save_i = i;
s->save_j = j;
s->save_t = t;
s->save_alphaSize = alphaSize;
s->save_nGroups = nGroups;
s->save_nSelectors = nSelectors;
s->save_EOB = EOB;
s->save_groupNo = groupNo;
s->save_groupPos = groupPos;
s->save_nextSym = nextSym;
s->save_nblockMAX = nblockMAX;
s->save_nblock = nblock;
s->save_es = es;
s->save_N = N;
s->save_curr = curr;
s->save_zt = zt;
s->save_zn = zn;
s->save_zvec = zvec;
s->save_zj = zj;
s->save_gSel = gSel;
s->save_gMinlen = gMinlen;
s->save_gLimit = gLimit;
s->save_gBase = gBase;
s->save_gPerm = gPerm;
return retVal;
}
/*-------------------------------------------------------------*/
/*--- end decompress.c ---*/
/*-------------------------------------------------------------*/
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