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Diffstat (limited to 'archival/libarchive/lzo1x_9x.c')
| -rw-r--r-- | archival/libarchive/lzo1x_9x.c | 921 |
1 files changed, 921 insertions, 0 deletions
diff --git a/archival/libarchive/lzo1x_9x.c b/archival/libarchive/lzo1x_9x.c new file mode 100644 index 0000000..4832051 --- /dev/null +++ b/archival/libarchive/lzo1x_9x.c @@ -0,0 +1,921 @@ +/* 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); +} |