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author | Denys Vlasenko | 2010-11-03 02:27:49 +0100 |
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committer | Denys Vlasenko | 2010-11-03 02:27:49 +0100 |
commit | 5e9934028aa030312a1a2e2e32d5ceade8672beb (patch) | |
tree | 52f384d6c8e695fa2be1dbbc0a7e21e85033f3b2 /archival/lzo1x_9x.c | |
parent | db5fe62b6d9977304b864f961dae71232091b26c (diff) | |
download | busybox-5e9934028aa030312a1a2e2e32d5ceade8672beb.zip busybox-5e9934028aa030312a1a2e2e32d5ceade8672beb.tar.gz |
*: move lzo compressor code to archival/libunarchive/. No code changes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival/lzo1x_9x.c')
-rw-r--r-- | archival/lzo1x_9x.c | 921 |
1 files changed, 0 insertions, 921 deletions
diff --git a/archival/lzo1x_9x.c b/archival/lzo1x_9x.c deleted file mode 100644 index 4832051..0000000 --- a/archival/lzo1x_9x.c +++ /dev/null @@ -1,921 +0,0 @@ -/* 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); -} |