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-rw-r--r--archival/lzo1x_9x.c921
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diff --git a/archival/lzo1x_9x.c b/archival/lzo1x_9x.c
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--- a/archival/lzo1x_9x.c
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-/* lzo1x_9x.c -- implementation of the LZO1X-999 compression algorithm
-
- This file is part of the LZO real-time data compression library.
-
- Copyright (C) 2008 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2007 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2006 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2005 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2004 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2003 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2002 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2001 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 2000 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 1999 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 1998 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 1997 Markus Franz Xaver Johannes Oberhumer
- Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
- All Rights Reserved.
-
- The LZO library is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of
- the License, or (at your option) any later version.
-
- The LZO library 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 for more details.
-
- You should have received a copy of the GNU General Public License
- along with the LZO library; see the file COPYING.
- If not, write to the Free Software Foundation, Inc.,
- 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
-
- Markus F.X.J. Oberhumer
- <markus@oberhumer.com>
- http://www.oberhumer.com/opensource/lzo/
-*/
-#include "libbb.h"
-
-/* The following is probably only safe on Intel-compatible processors ... */
-#define LZO_UNALIGNED_OK_2
-#define LZO_UNALIGNED_OK_4
-
-#include "liblzo.h"
-
-#define LZO_MAX(a,b) ((a) >= (b) ? (a) : (b))
-#define LZO_MIN(a,b) ((a) <= (b) ? (a) : (b))
-#define LZO_MAX3(a,b,c) ((a) >= (b) ? LZO_MAX(a,c) : LZO_MAX(b,c))
-
-/***********************************************************************
-//
-************************************************************************/
-#define SWD_N M4_MAX_OFFSET /* size of ring buffer */
-#define SWD_F 2048 /* upper limit for match length */
-
-#define SWD_BEST_OFF (LZO_MAX3(M2_MAX_LEN, M3_MAX_LEN, M4_MAX_LEN) + 1)
-
-typedef struct {
- int init;
-
- unsigned look; /* bytes in lookahead buffer */
-
- unsigned m_len;
- unsigned m_off;
-
- const uint8_t *bp;
- const uint8_t *ip;
- const uint8_t *in;
- const uint8_t *in_end;
- uint8_t *out;
-
- unsigned r1_lit;
-
-} lzo1x_999_t;
-
-#define getbyte(c) ((c).ip < (c).in_end ? *((c).ip)++ : (-1))
-
-/* lzo_swd.c -- sliding window dictionary */
-
-/***********************************************************************
-//
-************************************************************************/
-#define SWD_UINT_MAX USHRT_MAX
-
-#ifndef SWD_HSIZE
-# define SWD_HSIZE 16384
-#endif
-#ifndef SWD_MAX_CHAIN
-# define SWD_MAX_CHAIN 2048
-#endif
-
-#define HEAD3(b, p) \
- ( ((0x9f5f * ((((b[p]<<5)^b[p+1])<<5) ^ b[p+2])) >> 5) & (SWD_HSIZE-1) )
-
-#if defined(LZO_UNALIGNED_OK_2)
-# define HEAD2(b,p) (* (uint16_t *) &(b[p]))
-#else
-# define HEAD2(b,p) (b[p] ^ ((unsigned)b[p+1]<<8))
-#endif
-#define NIL2 SWD_UINT_MAX
-
-typedef struct lzo_swd {
- /* public - "built-in" */
-
- /* public - configuration */
- unsigned max_chain;
- int use_best_off;
-
- /* public - output */
- unsigned m_len;
- unsigned m_off;
- unsigned look;
- int b_char;
-#if defined(SWD_BEST_OFF)
- unsigned best_off[SWD_BEST_OFF];
-#endif
-
- /* semi public */
- lzo1x_999_t *c;
- unsigned m_pos;
-#if defined(SWD_BEST_OFF)
- unsigned best_pos[SWD_BEST_OFF];
-#endif
-
- /* private */
- unsigned ip; /* input pointer (lookahead) */
- unsigned bp; /* buffer pointer */
- unsigned rp; /* remove pointer */
-
- unsigned node_count;
- unsigned first_rp;
-
- uint8_t b[SWD_N + SWD_F];
- uint8_t b_wrap[SWD_F]; /* must follow b */
- uint16_t head3[SWD_HSIZE];
- uint16_t succ3[SWD_N + SWD_F];
- uint16_t best3[SWD_N + SWD_F];
- uint16_t llen3[SWD_HSIZE];
-#ifdef HEAD2
- uint16_t head2[65536L];
-#endif
-} lzo_swd_t, *lzo_swd_p;
-
-#define SIZEOF_LZO_SWD_T (sizeof(lzo_swd_t))
-
-
-/* Access macro for head3.
- * head3[key] may be uninitialized, but then its value will never be used.
- */
-#define s_get_head3(s,key) s->head3[key]
-
-
-/***********************************************************************
-//
-************************************************************************/
-#define B_SIZE (SWD_N + SWD_F)
-
-static int swd_init(lzo_swd_p s)
-{
- /* defaults */
- s->node_count = SWD_N;
-
- memset(s->llen3, 0, sizeof(s->llen3[0]) * (unsigned)SWD_HSIZE);
-#ifdef HEAD2
- memset(s->head2, 0xff, sizeof(s->head2[0]) * 65536L);
- assert(s->head2[0] == NIL2);
-#endif
-
- s->ip = 0;
- s->bp = s->ip;
- s->first_rp = s->ip;
-
- assert(s->ip + SWD_F <= B_SIZE);
- s->look = (unsigned) (s->c->in_end - s->c->ip);
- if (s->look > 0) {
- if (s->look > SWD_F)
- s->look = SWD_F;
- memcpy(&s->b[s->ip], s->c->ip, s->look);
- s->c->ip += s->look;
- s->ip += s->look;
- }
- if (s->ip == B_SIZE)
- s->ip = 0;
-
- s->rp = s->first_rp;
- if (s->rp >= s->node_count)
- s->rp -= s->node_count;
- else
- s->rp += B_SIZE - s->node_count;
-
- return LZO_E_OK;
-}
-
-#define swd_pos2off(s,pos) \
- (s->bp > (pos) ? s->bp - (pos) : B_SIZE - ((pos) - s->bp))
-
-
-/***********************************************************************
-//
-************************************************************************/
-static void swd_getbyte(lzo_swd_p s)
-{
- int c;
-
- if ((c = getbyte(*(s->c))) < 0) {
- if (s->look > 0)
- --s->look;
- } else {
- s->b[s->ip] = c;
- if (s->ip < SWD_F)
- s->b_wrap[s->ip] = c;
- }
- if (++s->ip == B_SIZE)
- s->ip = 0;
- if (++s->bp == B_SIZE)
- s->bp = 0;
- if (++s->rp == B_SIZE)
- s->rp = 0;
-}
-
-
-/***********************************************************************
-// remove node from lists
-************************************************************************/
-static void swd_remove_node(lzo_swd_p s, unsigned node)
-{
- if (s->node_count == 0) {
- unsigned key;
-
- key = HEAD3(s->b,node);
- assert(s->llen3[key] > 0);
- --s->llen3[key];
-
-#ifdef HEAD2
- key = HEAD2(s->b,node);
- assert(s->head2[key] != NIL2);
- if ((unsigned) s->head2[key] == node)
- s->head2[key] = NIL2;
-#endif
- } else
- --s->node_count;
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-static void swd_accept(lzo_swd_p s, unsigned n)
-{
- assert(n <= s->look);
-
- while (n--) {
- unsigned key;
-
- swd_remove_node(s,s->rp);
-
- /* add bp into HEAD3 */
- key = HEAD3(s->b, s->bp);
- s->succ3[s->bp] = s_get_head3(s, key);
- s->head3[key] = s->bp;
- s->best3[s->bp] = SWD_F + 1;
- s->llen3[key]++;
- assert(s->llen3[key] <= SWD_N);
-
-#ifdef HEAD2
- /* add bp into HEAD2 */
- key = HEAD2(s->b, s->bp);
- s->head2[key] = s->bp;
-#endif
-
- swd_getbyte(s);
- }
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-static void swd_search(lzo_swd_p s, unsigned node, unsigned cnt)
-{
- const uint8_t *p1;
- const uint8_t *p2;
- const uint8_t *px;
- unsigned m_len = s->m_len;
- const uint8_t *b = s->b;
- const uint8_t *bp = s->b + s->bp;
- const uint8_t *bx = s->b + s->bp + s->look;
- unsigned char scan_end1;
-
- assert(s->m_len > 0);
-
- scan_end1 = bp[m_len - 1];
- for ( ; cnt-- > 0; node = s->succ3[node]) {
- p1 = bp;
- p2 = b + node;
- px = bx;
-
- assert(m_len < s->look);
-
- if (p2[m_len - 1] == scan_end1
- && p2[m_len] == p1[m_len]
- && p2[0] == p1[0]
- && p2[1] == p1[1]
- ) {
- unsigned i;
- assert(lzo_memcmp(bp, &b[node], 3) == 0);
-
- p1 += 2; p2 += 2;
- do {} while (++p1 < px && *p1 == *++p2);
- i = p1-bp;
-
- assert(lzo_memcmp(bp, &b[node], i) == 0);
-
-#if defined(SWD_BEST_OFF)
- if (i < SWD_BEST_OFF) {
- if (s->best_pos[i] == 0)
- s->best_pos[i] = node + 1;
- }
-#endif
- if (i > m_len) {
- s->m_len = m_len = i;
- s->m_pos = node;
- if (m_len == s->look)
- return;
- if (m_len >= SWD_F)
- return;
- if (m_len > (unsigned) s->best3[node])
- return;
- scan_end1 = bp[m_len - 1];
- }
- }
- }
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-#ifdef HEAD2
-
-static int swd_search2(lzo_swd_p s)
-{
- unsigned key;
-
- assert(s->look >= 2);
- assert(s->m_len > 0);
-
- key = s->head2[HEAD2(s->b, s->bp)];
- if (key == NIL2)
- return 0;
- assert(lzo_memcmp(&s->b[s->bp], &s->b[key], 2) == 0);
-#if defined(SWD_BEST_OFF)
- if (s->best_pos[2] == 0)
- s->best_pos[2] = key + 1;
-#endif
-
- if (s->m_len < 2) {
- s->m_len = 2;
- s->m_pos = key;
- }
- return 1;
-}
-
-#endif
-
-
-/***********************************************************************
-//
-************************************************************************/
-static void swd_findbest(lzo_swd_p s)
-{
- unsigned key;
- unsigned cnt, node;
- unsigned len;
-
- assert(s->m_len > 0);
-
- /* get current head, add bp into HEAD3 */
- key = HEAD3(s->b,s->bp);
- node = s->succ3[s->bp] = s_get_head3(s, key);
- cnt = s->llen3[key]++;
- assert(s->llen3[key] <= SWD_N + SWD_F);
- if (cnt > s->max_chain)
- cnt = s->max_chain;
- s->head3[key] = s->bp;
-
- s->b_char = s->b[s->bp];
- len = s->m_len;
- if (s->m_len >= s->look) {
- if (s->look == 0)
- s->b_char = -1;
- s->m_off = 0;
- s->best3[s->bp] = SWD_F + 1;
- } else {
-#ifdef HEAD2
- if (swd_search2(s))
-#endif
- if (s->look >= 3)
- swd_search(s, node, cnt);
- if (s->m_len > len)
- s->m_off = swd_pos2off(s,s->m_pos);
- s->best3[s->bp] = s->m_len;
-
-#if defined(SWD_BEST_OFF)
- if (s->use_best_off) {
- int i;
- for (i = 2; i < SWD_BEST_OFF; i++) {
- if (s->best_pos[i] > 0)
- s->best_off[i] = swd_pos2off(s, s->best_pos[i]-1);
- else
- s->best_off[i] = 0;
- }
- }
-#endif
- }
-
- swd_remove_node(s,s->rp);
-
-#ifdef HEAD2
- /* add bp into HEAD2 */
- key = HEAD2(s->b, s->bp);
- s->head2[key] = s->bp;
-#endif
-}
-
-#undef HEAD3
-#undef HEAD2
-#undef s_get_head3
-
-
-/***********************************************************************
-//
-************************************************************************/
-static int init_match(lzo1x_999_t *c, lzo_swd_p s, uint32_t use_best_off)
-{
- int r;
-
- assert(!c->init);
- c->init = 1;
-
- s->c = c;
-
- r = swd_init(s);
- if (r != 0)
- return r;
-
- s->use_best_off = use_best_off;
- return r;
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-static int find_match(lzo1x_999_t *c, lzo_swd_p s,
- unsigned this_len, unsigned skip)
-{
- assert(c->init);
-
- if (skip > 0) {
- assert(this_len >= skip);
- swd_accept(s, this_len - skip);
- } else {
- assert(this_len <= 1);
- }
-
- s->m_len = 1;
- s->m_len = 1;
-#ifdef SWD_BEST_OFF
- if (s->use_best_off)
- memset(s->best_pos, 0, sizeof(s->best_pos));
-#endif
- swd_findbest(s);
- c->m_len = s->m_len;
- c->m_off = s->m_off;
-
- swd_getbyte(s);
-
- if (s->b_char < 0) {
- c->look = 0;
- c->m_len = 0;
- } else {
- c->look = s->look + 1;
- }
- c->bp = c->ip - c->look;
-
- return LZO_E_OK;
-}
-
-/* this is a public functions, but there is no prototype in a header file */
-static int lzo1x_999_compress_internal(const uint8_t *in , unsigned in_len,
- uint8_t *out, unsigned *out_len,
- void *wrkmem,
- unsigned good_length,
- unsigned max_lazy,
- unsigned max_chain,
- uint32_t use_best_off);
-
-
-/***********************************************************************
-//
-************************************************************************/
-static uint8_t *code_match(lzo1x_999_t *c,
- uint8_t *op, unsigned m_len, unsigned m_off)
-{
- assert(op > c->out);
- if (m_len == 2) {
- assert(m_off <= M1_MAX_OFFSET);
- assert(c->r1_lit > 0);
- assert(c->r1_lit < 4);
- m_off -= 1;
- *op++ = M1_MARKER | ((m_off & 3) << 2);
- *op++ = m_off >> 2;
- } else if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
- assert(m_len >= 3);
- m_off -= 1;
- *op++ = ((m_len - 1) << 5) | ((m_off & 7) << 2);
- *op++ = m_off >> 3;
- assert(op[-2] >= M2_MARKER);
- } else if (m_len == M2_MIN_LEN && m_off <= MX_MAX_OFFSET && c->r1_lit >= 4) {
- assert(m_len == 3);
- assert(m_off > M2_MAX_OFFSET);
- m_off -= 1 + M2_MAX_OFFSET;
- *op++ = M1_MARKER | ((m_off & 3) << 2);
- *op++ = m_off >> 2;
- } else if (m_off <= M3_MAX_OFFSET) {
- assert(m_len >= 3);
- m_off -= 1;
- if (m_len <= M3_MAX_LEN)
- *op++ = M3_MARKER | (m_len - 2);
- else {
- m_len -= M3_MAX_LEN;
- *op++ = M3_MARKER | 0;
- while (m_len > 255) {
- m_len -= 255;
- *op++ = 0;
- }
- assert(m_len > 0);
- *op++ = m_len;
- }
- *op++ = m_off << 2;
- *op++ = m_off >> 6;
- } else {
- unsigned k;
-
- assert(m_len >= 3);
- assert(m_off > 0x4000);
- assert(m_off <= 0xbfff);
- m_off -= 0x4000;
- k = (m_off & 0x4000) >> 11;
- if (m_len <= M4_MAX_LEN)
- *op++ = M4_MARKER | k | (m_len - 2);
- else {
- m_len -= M4_MAX_LEN;
- *op++ = M4_MARKER | k | 0;
- while (m_len > 255) {
- m_len -= 255;
- *op++ = 0;
- }
- assert(m_len > 0);
- *op++ = m_len;
- }
- *op++ = m_off << 2;
- *op++ = m_off >> 6;
- }
-
- return op;
-}
-
-
-static uint8_t *STORE_RUN(lzo1x_999_t *c, uint8_t *op,
- const uint8_t *ii, unsigned t)
-{
- if (op == c->out && t <= 238) {
- *op++ = 17 + t;
- } else if (t <= 3) {
- op[-2] |= t;
- } else if (t <= 18) {
- *op++ = t - 3;
- } else {
- unsigned tt = t - 18;
-
- *op++ = 0;
- while (tt > 255) {
- tt -= 255;
- *op++ = 0;
- }
- assert(tt > 0);
- *op++ = tt;
- }
- do *op++ = *ii++; while (--t > 0);
-
- return op;
-}
-
-
-static uint8_t *code_run(lzo1x_999_t *c, uint8_t *op, const uint8_t *ii,
- unsigned lit)
-{
- if (lit > 0) {
- assert(m_len >= 2);
- op = STORE_RUN(c, op, ii, lit);
- } else {
- assert(m_len >= 3);
- }
- c->r1_lit = lit;
-
- return op;
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-static int len_of_coded_match(unsigned m_len, unsigned m_off, unsigned lit)
-{
- int n = 4;
-
- if (m_len < 2)
- return -1;
- if (m_len == 2)
- return (m_off <= M1_MAX_OFFSET && lit > 0 && lit < 4) ? 2 : -1;
- if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET)
- return 2;
- if (m_len == M2_MIN_LEN && m_off <= MX_MAX_OFFSET && lit >= 4)
- return 2;
- if (m_off <= M3_MAX_OFFSET) {
- if (m_len <= M3_MAX_LEN)
- return 3;
- m_len -= M3_MAX_LEN;
- } else if (m_off <= M4_MAX_OFFSET) {
- if (m_len <= M4_MAX_LEN)
- return 3;
- m_len -= M4_MAX_LEN;
- } else
- return -1;
- while (m_len > 255) {
- m_len -= 255;
- n++;
- }
- return n;
-}
-
-
-static int min_gain(unsigned ahead, unsigned lit1,
- unsigned lit2, int l1, int l2, int l3)
-{
- int lazy_match_min_gain = 0;
-
- assert (ahead >= 1);
- lazy_match_min_gain += ahead;
-
- if (lit1 <= 3)
- lazy_match_min_gain += (lit2 <= 3) ? 0 : 2;
- else if (lit1 <= 18)
- lazy_match_min_gain += (lit2 <= 18) ? 0 : 1;
-
- lazy_match_min_gain += (l2 - l1) * 2;
- if (l3 > 0)
- lazy_match_min_gain -= (ahead - l3) * 2;
-
- if (lazy_match_min_gain < 0)
- lazy_match_min_gain = 0;
-
- return lazy_match_min_gain;
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-#if defined(SWD_BEST_OFF)
-
-static void better_match(const lzo_swd_p swd,
- unsigned *m_len, unsigned *m_off)
-{
- if (*m_len <= M2_MIN_LEN)
- return;
-
- if (*m_off <= M2_MAX_OFFSET)
- return;
-
- /* M3/M4 -> M2 */
- if (*m_off > M2_MAX_OFFSET
- && *m_len >= M2_MIN_LEN + 1 && *m_len <= M2_MAX_LEN + 1
- && swd->best_off[*m_len-1] && swd->best_off[*m_len-1] <= M2_MAX_OFFSET
- ) {
- *m_len = *m_len - 1;
- *m_off = swd->best_off[*m_len];
- return;
- }
-
- /* M4 -> M2 */
- if (*m_off > M3_MAX_OFFSET
- && *m_len >= M4_MAX_LEN + 1 && *m_len <= M2_MAX_LEN + 2
- && swd->best_off[*m_len-2] && swd->best_off[*m_len-2] <= M2_MAX_OFFSET
- ) {
- *m_len = *m_len - 2;
- *m_off = swd->best_off[*m_len];
- return;
- }
- /* M4 -> M3 */
- if (*m_off > M3_MAX_OFFSET
- && *m_len >= M4_MAX_LEN + 1 && *m_len <= M3_MAX_LEN + 1
- && swd->best_off[*m_len-1] && swd->best_off[*m_len-1] <= M3_MAX_OFFSET
- ) {
- *m_len = *m_len - 1;
- *m_off = swd->best_off[*m_len];
- }
-}
-
-#endif
-
-
-/***********************************************************************
-//
-************************************************************************/
-static int lzo1x_999_compress_internal(const uint8_t *in, unsigned in_len,
- uint8_t *out, unsigned *out_len,
- void *wrkmem,
- unsigned good_length,
- unsigned max_lazy,
- unsigned max_chain,
- uint32_t use_best_off)
-{
- uint8_t *op;
- const uint8_t *ii;
- unsigned lit;
- unsigned m_len, m_off;
- lzo1x_999_t cc;
- lzo1x_999_t *const c = &cc;
- const lzo_swd_p swd = (lzo_swd_p) wrkmem;
- int r;
-
- c->init = 0;
- c->ip = c->in = in;
- c->in_end = in + in_len;
- c->out = out;
-
- op = out;
- ii = c->ip; /* point to start of literal run */
- lit = 0;
- c->r1_lit = 0;
-
- r = init_match(c, swd, use_best_off);
- if (r != 0)
- return r;
- swd->max_chain = max_chain;
-
- r = find_match(c, swd, 0, 0);
- if (r != 0)
- return r;
-
- while (c->look > 0) {
- unsigned ahead;
- unsigned max_ahead;
- int l1, l2, l3;
-
- m_len = c->m_len;
- m_off = c->m_off;
-
- assert(c->bp == c->ip - c->look);
- assert(c->bp >= in);
- if (lit == 0)
- ii = c->bp;
- assert(ii + lit == c->bp);
- assert(swd->b_char == *(c->bp));
-
- if (m_len < 2
- || (m_len == 2 && (m_off > M1_MAX_OFFSET || lit == 0 || lit >= 4))
- /* Do not accept this match for compressed-data compatibility
- * with LZO v1.01 and before
- * [ might be a problem for decompress() and optimize() ]
- */
- || (m_len == 2 && op == out)
- || (op == out && lit == 0)
- ) {
- /* a literal */
- m_len = 0;
- }
- else if (m_len == M2_MIN_LEN) {
- /* compression ratio improves if we code a literal in some cases */
- if (m_off > MX_MAX_OFFSET && lit >= 4)
- m_len = 0;
- }
-
- if (m_len == 0) {
- /* a literal */
- lit++;
- swd->max_chain = max_chain;
- r = find_match(c, swd, 1, 0);
- assert(r == 0);
- continue;
- }
-
- /* a match */
-#if defined(SWD_BEST_OFF)
- if (swd->use_best_off)
- better_match(swd, &m_len, &m_off);
-#endif
-
- /* shall we try a lazy match ? */
- ahead = 0;
- if (m_len >= max_lazy) {
- /* no */
- l1 = 0;
- max_ahead = 0;
- } else {
- /* yes, try a lazy match */
- l1 = len_of_coded_match(m_len, m_off, lit);
- assert(l1 > 0);
- max_ahead = LZO_MIN(2, (unsigned)l1 - 1);
- }
-
-
- while (ahead < max_ahead && c->look > m_len) {
- int lazy_match_min_gain;
-
- if (m_len >= good_length)
- swd->max_chain = max_chain >> 2;
- else
- swd->max_chain = max_chain;
- r = find_match(c, swd, 1, 0);
- ahead++;
-
- assert(r == 0);
- assert(c->look > 0);
- assert(ii + lit + ahead == c->bp);
-
- if (c->m_len < m_len)
- continue;
- if (c->m_len == m_len && c->m_off >= m_off)
- continue;
-#if defined(SWD_BEST_OFF)
- if (swd->use_best_off)
- better_match(swd, &c->m_len, &c->m_off);
-#endif
- l2 = len_of_coded_match(c->m_len, c->m_off, lit+ahead);
- if (l2 < 0)
- continue;
-
- /* compressed-data compatibility [see above] */
- l3 = (op == out) ? -1 : len_of_coded_match(ahead, m_off, lit);
-
- lazy_match_min_gain = min_gain(ahead, lit, lit+ahead, l1, l2, l3);
- if (c->m_len >= m_len + lazy_match_min_gain) {
- if (l3 > 0) {
- /* code previous run */
- op = code_run(c, op, ii, lit);
- lit = 0;
- /* code shortened match */
- op = code_match(c, op, ahead, m_off);
- } else {
- lit += ahead;
- assert(ii + lit == c->bp);
- }
- goto lazy_match_done;
- }
- }
-
- assert(ii + lit + ahead == c->bp);
-
- /* 1 - code run */
- op = code_run(c, op, ii, lit);
- lit = 0;
-
- /* 2 - code match */
- op = code_match(c, op, m_len, m_off);
- swd->max_chain = max_chain;
- r = find_match(c, swd, m_len, 1+ahead);
- assert(r == 0);
-
- lazy_match_done: ;
- }
-
- /* store final run */
- if (lit > 0)
- op = STORE_RUN(c, op, ii, lit);
-
-#if defined(LZO_EOF_CODE)
- *op++ = M4_MARKER | 1;
- *op++ = 0;
- *op++ = 0;
-#endif
-
- *out_len = op - out;
-
- return LZO_E_OK;
-}
-
-
-/***********************************************************************
-//
-************************************************************************/
-int lzo1x_999_compress_level(const uint8_t *in, unsigned in_len,
- uint8_t *out, unsigned *out_len,
- void *wrkmem,
- int compression_level)
-{
- static const struct {
- uint16_t good_length;
- uint16_t max_lazy;
- uint16_t max_chain;
- uint16_t use_best_off;
- } c[3] = {
- { 8, 32, 256, 0 },
- { 32, 128, 2048, 1 },
- { SWD_F, SWD_F, 4096, 1 } /* max. compression */
- };
-
- if (compression_level < 7 || compression_level > 9)
- return LZO_E_ERROR;
-
- compression_level -= 7;
- return lzo1x_999_compress_internal(in, in_len, out, out_len, wrkmem,
- c[compression_level].good_length,
- c[compression_level].max_lazy,
- c[compression_level].max_chain,
- c[compression_level].use_best_off);
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-05 23:01:53 +0000