ReactOS 0.4.15-dev-8236-g99f0937
lzx.h File Reference
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Macros

#define DECR_OK   (0)
 
#define DECR_DATAFORMAT   (1)
 
#define DECR_ILLEGALDATA   (2)
 
#define DECR_NOMEMORY   (3)
 

Functions

struct LZXstateLZXinit (int window)
 
void LZXteardown (struct LZXstate *pState)
 
int LZXreset (struct LZXstate *pState)
 
int LZXdecompress (struct LZXstate *pState, unsigned char *inpos, unsigned char *outpos, int inlen, int outlen)
 

Macro Definition Documentation

◆ DECR_DATAFORMAT

#define DECR_DATAFORMAT   (1)

Definition at line 37 of file lzx.h.

◆ DECR_ILLEGALDATA

#define DECR_ILLEGALDATA   (2)

Definition at line 38 of file lzx.h.

◆ DECR_NOMEMORY

#define DECR_NOMEMORY   (3)

Definition at line 39 of file lzx.h.

◆ DECR_OK

#define DECR_OK   (0)

Definition at line 36 of file lzx.h.

Function Documentation

◆ LZXdecompress()

int LZXdecompress ( struct LZXstate pState,
unsigned char inpos,
unsigned char outpos,
int  inlen,
int  outlen 
)

Definition at line 461 of file lzx.c.

461 {
462 UBYTE *endinp = inpos + inlen;
463 UBYTE *window = pState->window;
464 UBYTE *runsrc, *rundest;
465 UWORD *hufftbl; /* used in READ_HUFFSYM macro as chosen decoding table */
466
467 ULONG window_posn = pState->window_posn;
468 ULONG window_size = pState->window_size;
469 ULONG R0 = pState->R0;
470 ULONG R1 = pState->R1;
471 ULONG R2 = pState->R2;
472
473 register ULONG bitbuf;
474 register int bitsleft;
475 ULONG match_offset, i,j,k; /* ijk used in READ_HUFFSYM macro */
476 struct lzx_bits lb; /* used in READ_LENGTHS macro */
477
478 int togo = outlen, this_run, main_element, aligned_bits;
479 int match_length, length_footer, extra, verbatim_bits;
480 int copy_length;
481
483
484 /* read header if necessary */
485 if (!pState->header_read) {
486 i = j = 0;
487 READ_BITS(k, 1); if (k) { READ_BITS(i,16); READ_BITS(j,16); }
488 pState->intel_filesize = (i << 16) | j; /* or 0 if not encoded */
489 pState->header_read = 1;
490 }
491
492 /* main decoding loop */
493 while (togo > 0) {
494 /* last block finished, new block expected */
495 if (pState->block_remaining == 0) {
496 if (pState->block_type == LZX_BLOCKTYPE_UNCOMPRESSED) {
497 if (pState->block_length & 1) inpos++; /* realign bitstream to word */
499 }
500
501 READ_BITS(pState->block_type, 3);
502 READ_BITS(i, 16);
503 READ_BITS(j, 8);
504 pState->block_remaining = pState->block_length = (i << 8) | j;
505
506 switch (pState->block_type) {
508 for (i = 0; i < 8; i++) { READ_BITS(j, 3); LENTABLE(ALIGNED)[i] = j; }
510 /* rest of aligned header is same as verbatim */
511
513 READ_LENGTHS(MAINTREE, 0, 256);
514 READ_LENGTHS(MAINTREE, 256, pState->main_elements);
515 BUILD_TABLE(MAINTREE);
516 if (LENTABLE(MAINTREE)[0xE8] != 0) pState->intel_started = 1;
517
520 break;
521
523 pState->intel_started = 1; /* because we can't assume otherwise */
524 ENSURE_BITS(16); /* get up to 16 pad bits into the buffer */
525 if (bitsleft > 16) inpos -= 2; /* and align the bitstream! */
526 R0 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
527 R1 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
528 R2 = inpos[0]|(inpos[1]<<8)|(inpos[2]<<16)|(inpos[3]<<24);inpos+=4;
529 break;
530
531 default:
532 return DECR_ILLEGALDATA;
533 }
534 }
535
536 /* buffer exhaustion check */
537 if (inpos > endinp) {
538 /* it's possible to have a file where the next run is less than
539 * 16 bits in size. In this case, the READ_HUFFSYM() macro used
540 * in building the tables will exhaust the buffer, so we should
541 * allow for this, but not allow those accidentally read bits to
542 * be used (so we check that there are at least 16 bits
543 * remaining - in this boundary case they aren't really part of
544 * the compressed data)
545 */
546 if (inpos > (endinp+2) || bitsleft < 16) return DECR_ILLEGALDATA;
547 }
548
549 while ((this_run = pState->block_remaining) > 0 && togo > 0) {
550 if (this_run > togo) this_run = togo;
551 togo -= this_run;
552 pState->block_remaining -= this_run;
553
554 /* apply 2^x-1 mask */
555 window_posn &= window_size - 1;
556 /* runs can't straddle the window wraparound */
557 if ((window_posn + this_run) > window_size)
558 return DECR_DATAFORMAT;
559
560 switch (pState->block_type) {
561
563 while (this_run > 0) {
564 READ_HUFFSYM(MAINTREE, main_element);
565
566 if (main_element < LZX_NUM_CHARS) {
567 /* literal: 0 to LZX_NUM_CHARS-1 */
568 window[window_posn++] = main_element;
569 this_run--;
570 }
571 else {
572 /* match: LZX_NUM_CHARS + ((slot<<3) | length_header (3 bits)) */
573 main_element -= LZX_NUM_CHARS;
574
575 match_length = main_element & LZX_NUM_PRIMARY_LENGTHS;
576 if (match_length == LZX_NUM_PRIMARY_LENGTHS) {
577 READ_HUFFSYM(LENGTH, length_footer);
578 match_length += length_footer;
579 }
580 match_length += LZX_MIN_MATCH;
581
582 match_offset = main_element >> 3;
583
584 if (match_offset > 2) {
585 /* not repeated offset */
586 if (match_offset != 3) {
587 extra = extra_bits[match_offset];
588 READ_BITS(verbatim_bits, extra);
589 match_offset = position_base[match_offset] - 2 + verbatim_bits;
590 }
591 else {
592 match_offset = 1;
593 }
594
595 /* update repeated offset LRU queue */
596 R2 = R1; R1 = R0; R0 = match_offset;
597 }
598 else if (match_offset == 0) {
599 match_offset = R0;
600 }
601 else if (match_offset == 1) {
602 match_offset = R1;
603 R1 = R0; R0 = match_offset;
604 }
605 else /* match_offset == 2 */ {
606 match_offset = R2;
607 R2 = R0; R0 = match_offset;
608 }
609
610 rundest = window + window_posn;
611 this_run -= match_length;
612
613 /* copy any wrapped around source data */
614 if (window_posn >= match_offset) {
615 /* no wrap */
616 runsrc = rundest - match_offset;
617 } else {
618 runsrc = rundest + (window_size - match_offset);
619 copy_length = match_offset - window_posn;
620 if (copy_length < match_length) {
621 match_length -= copy_length;
622 window_posn += copy_length;
623 while (copy_length-- > 0) *rundest++ = *runsrc++;
624 runsrc = window;
625 }
626 }
627 window_posn += match_length;
628
629 /* copy match data - no worries about destination wraps */
630 while (match_length-- > 0) *rundest++ = *runsrc++;
631
632 }
633 }
634 break;
635
637 while (this_run > 0) {
638 READ_HUFFSYM(MAINTREE, main_element);
639
640 if (main_element < LZX_NUM_CHARS) {
641 /* literal: 0 to LZX_NUM_CHARS-1 */
642 window[window_posn++] = main_element;
643 this_run--;
644 }
645 else {
646 /* match: LZX_NUM_CHARS + ((slot<<3) | length_header (3 bits)) */
647 main_element -= LZX_NUM_CHARS;
648
649 match_length = main_element & LZX_NUM_PRIMARY_LENGTHS;
650 if (match_length == LZX_NUM_PRIMARY_LENGTHS) {
651 READ_HUFFSYM(LENGTH, length_footer);
652 match_length += length_footer;
653 }
654 match_length += LZX_MIN_MATCH;
655
656 match_offset = main_element >> 3;
657
658 if (match_offset > 2) {
659 /* not repeated offset */
660 extra = extra_bits[match_offset];
661 match_offset = position_base[match_offset] - 2;
662 if (extra > 3) {
663 /* verbatim and aligned bits */
664 extra -= 3;
665 READ_BITS(verbatim_bits, extra);
666 match_offset += (verbatim_bits << 3);
667 READ_HUFFSYM(ALIGNED, aligned_bits);
668 match_offset += aligned_bits;
669 }
670 else if (extra == 3) {
671 /* aligned bits only */
672 READ_HUFFSYM(ALIGNED, aligned_bits);
673 match_offset += aligned_bits;
674 }
675 else if (extra > 0) { /* extra==1, extra==2 */
676 /* verbatim bits only */
677 READ_BITS(verbatim_bits, extra);
678 match_offset += verbatim_bits;
679 }
680 else /* extra == 0 */ {
681 /* ??? */
682 match_offset = 1;
683 }
684
685 /* update repeated offset LRU queue */
686 R2 = R1; R1 = R0; R0 = match_offset;
687 }
688 else if (match_offset == 0) {
689 match_offset = R0;
690 }
691 else if (match_offset == 1) {
692 match_offset = R1;
693 R1 = R0; R0 = match_offset;
694 }
695 else /* match_offset == 2 */ {
696 match_offset = R2;
697 R2 = R0; R0 = match_offset;
698 }
699
700 rundest = window + window_posn;
701 this_run -= match_length;
702
703 /* copy any wrapped around source data */
704 if (window_posn >= match_offset) {
705 /* no wrap */
706 runsrc = rundest - match_offset;
707 } else {
708 runsrc = rundest + (window_size - match_offset);
709 copy_length = match_offset - window_posn;
710 if (copy_length < match_length) {
711 match_length -= copy_length;
712 window_posn += copy_length;
713 while (copy_length-- > 0) *rundest++ = *runsrc++;
714 runsrc = window;
715 }
716 }
717 window_posn += match_length;
718
719 /* copy match data - no worries about destination wraps */
720 while (match_length-- > 0) *rundest++ = *runsrc++;
721
722 }
723 }
724 break;
725
727 if ((inpos + this_run) > endinp) return DECR_ILLEGALDATA;
728 memcpy(window + window_posn, inpos, (size_t) this_run);
729 inpos += this_run; window_posn += this_run;
730 break;
731
732 default:
733 return DECR_ILLEGALDATA; /* might as well */
734 }
735
736 }
737 }
738
739 if (togo != 0) return DECR_ILLEGALDATA;
740 memcpy(outpos, window + ((!window_posn) ? window_size : window_posn) - outlen, (size_t) outlen);
741
742 pState->window_posn = window_posn;
743 pState->R0 = R0;
744 pState->R1 = R1;
745 pState->R2 = R2;
746
747 /* intel E8 decoding */
748 if ((pState->frames_read++ < 32768) && pState->intel_filesize != 0) {
749 if (outlen <= 6 || !pState->intel_started) {
750 pState->intel_curpos += outlen;
751 }
752 else {
753 UBYTE *data = outpos;
754 UBYTE *dataend = data + outlen - 10;
755 LONG curpos = pState->intel_curpos;
756 LONG filesize = pState->intel_filesize;
757 LONG abs_off, rel_off;
758
759 pState->intel_curpos = curpos + outlen;
760
761 while (data < dataend) {
762 if (*data++ != 0xE8) { curpos++; continue; }
763 abs_off = data[0] | (data[1]<<8) | (data[2]<<16) | (data[3]<<24);
764 if ((abs_off >= -curpos) && (abs_off < filesize)) {
765 rel_off = (abs_off >= 0) ? abs_off - curpos : abs_off + filesize;
766 data[0] = (UBYTE) rel_off;
767 data[1] = (UBYTE) (rel_off >> 8);
768 data[2] = (UBYTE) (rel_off >> 16);
769 data[3] = (UBYTE) (rel_off >> 24);
770 }
771 data += 4;
772 curpos += 5;
773 }
774 }
775 }
776 return DECR_OK;
777}
#define DECR_OK
Definition: mszip.h:79
#define DECR_ILLEGALDATA
Definition: mszip.h:81
#define DECR_DATAFORMAT
Definition: mszip.h:80
@ LENGTH
Definition: inflate.c:185
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: gl.h:1950
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint GLint GLint j
Definition: glfuncs.h:250
@ extra
Definition: id3.c:95
#define LZX_NUM_CHARS
Definition: lzx.c:54
unsigned char UBYTE
Definition: lzx.c:48
#define READ_LENGTHS(tbl, first, last)
Definition: lzx.c:319
#define LZX_BLOCKTYPE_ALIGNED
Definition: lzx.c:57
#define LZX_NUM_SECONDARY_LENGTHS
Definition: lzx.c:62
#define READ_BITS(v, n)
Definition: lzx.c:272
#define LENTABLE(tbl)
Definition: lzx.c:284
#define LZX_BLOCKTYPE_VERBATIM
Definition: lzx.c:56
#define LZX_NUM_PRIMARY_LENGTHS
Definition: lzx.c:61
#define READ_HUFFSYM(tbl, var)
Definition: lzx.c:300
#define LZX_BLOCKTYPE_UNCOMPRESSED
Definition: lzx.c:58
static const ULONG position_base[51]
Definition: lzx.c:165
#define INIT_BITSTREAM
Definition: lzx.c:261
#define BUILD_TABLE(tbl)
Definition: lzx.c:291
unsigned short UWORD
Definition: lzx.c:49
#define LZX_MIN_MATCH
Definition: lzx.c:52
#define ENSURE_BITS(n)
Definition: lzx.c:263
static const UBYTE extra_bits[51]
Definition: lzx.c:158
#define memcpy(s1, s2, n)
Definition: mkisofs.h:878
static IHTMLWindow2 * window
Definition: events.c:77
int k
Definition: mpi.c:3369
#define ALIGNED(a)
Definition: optimize.h:190
long LONG
Definition: pedump.c:60
#define R1(v, w, x, y, z, i)
Definition: sha1.c:36
#define R2(v, w, x, y, z, i)
Definition: sha1.c:37
#define R0(v, w, x, y, z, i)
Definition: sha1.c:35
cab_ULONG block_remaining
Definition: cabinet.h:222
int header_read
Definition: cabinet.h:219
cab_UWORD main_elements
Definition: cabinet.h:218
cab_LONG intel_filesize
Definition: cabinet.h:224
cab_ULONG R0
Definition: cabinet.h:217
cab_LONG intel_curpos
Definition: cabinet.h:225
cab_UWORD block_type
Definition: cabinet.h:220
cab_ULONG R2
Definition: cabinet.h:217
cab_ULONG frames_read
Definition: cabinet.h:223
int intel_started
Definition: cabinet.h:226
cab_ULONG R1
Definition: cabinet.h:217
cab_UBYTE * window
Definition: cabinet.h:213
cab_ULONG window_size
Definition: cabinet.h:214
cab_ULONG block_length
Definition: cabinet.h:221
cab_ULONG window_posn
Definition: cabinet.h:216
uint32_t ULONG
Definition: typedefs.h:59

◆ LZXinit()

struct LZXstate * LZXinit ( int  window)

alternatively

Definition at line 172 of file lzx.c.

173{
174 struct LZXstate *pState=NULL;
175 int i, posn_slots;
176
177 /* allocate state and associated window */
178 pState = HeapAlloc(GetProcessHeap(), 0, sizeof(struct LZXstate));
179 if (!(pState->window = HeapAlloc(GetProcessHeap(), 0, wndsize)))
180 {
181 HeapFree(GetProcessHeap(), 0, pState);
182 return NULL;
183 }
184 pState->actual_size = wndsize;
185 pState->window_size = wndsize;
186
187 /* calculate required position slots */
188 posn_slots = i = 0;
189 while (i < wndsize) i += 1 << extra_bits[posn_slots++];
190
191 /* initialize other state */
192 pState->R0 = pState->R1 = pState->R2 = 1;
193 pState->main_elements = LZX_NUM_CHARS + (posn_slots << 3);
194 pState->header_read = 0;
195 pState->frames_read = 0;
196 pState->block_remaining = 0;
198 pState->intel_curpos = 0;
199 pState->intel_started = 0;
200 pState->window_posn = 0;
201
202 /* initialise tables to 0 (because deltas will be applied to them) */
203 for (i = 0; i < LZX_MAINTREE_MAXSYMBOLS; i++) pState->MAINTREE_len[i] = 0;
204 for (i = 0; i < LZX_LENGTH_MAXSYMBOLS; i++) pState->LENGTH_len[i] = 0;
205
206 return pState;
207}
#define NULL
Definition: types.h:112
#define GetProcessHeap()
Definition: compat.h:736
#define HeapAlloc
Definition: compat.h:733
#define HeapFree(x, y, z)
Definition: compat.h:735
#define LZX_BLOCKTYPE_INVALID
Definition: lzx.c:55
#define LZX_MAINTREE_MAXSYMBOLS
Definition: lzx.c:67
#define LZX_LENGTH_MAXSYMBOLS
Definition: lzx.c:69
#define for
Definition: utility.h:88
cab_ULONG actual_size
Definition: cabinet.h:215

◆ LZXreset()

int LZXreset ( struct LZXstate pState)

Definition at line 218 of file lzx.c.

219{
220 int i;
221
222 pState->R0 = pState->R1 = pState->R2 = 1;
223 pState->header_read = 0;
224 pState->frames_read = 0;
225 pState->block_remaining = 0;
227 pState->intel_curpos = 0;
228 pState->intel_started = 0;
229 pState->window_posn = 0;
230
231 for (i = 0; i < LZX_MAINTREE_MAXSYMBOLS + LZX_LENTABLE_SAFETY; i++) pState->MAINTREE_len[i] = 0;
232 for (i = 0; i < LZX_LENGTH_MAXSYMBOLS + LZX_LENTABLE_SAFETY; i++) pState->LENGTH_len[i] = 0;
233
234 return DECR_OK;
235}
#define LZX_LENTABLE_SAFETY
Definition: lzx.c:74

◆ LZXteardown()

void LZXteardown ( struct LZXstate pState)

Definition at line 209 of file lzx.c.

210{
211 if (pState)
212 {
213 HeapFree(GetProcessHeap(), 0, pState->window);
214 HeapFree(GetProcessHeap(), 0, pState);
215 }
216}