From 7c21a96e9afa3408ca0b459a392275aa0ae77608 Mon Sep 17 00:00:00 2001 From: Jens Arnold Date: Sun, 27 Nov 2005 23:41:55 +0000 Subject: Initial check-in of (stripped-down) UCL data compression library v 1.01 git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8087 a1c6a512-1295-4272-9138-f99709370657 --- tools/ucl/src/ucl_swd.ch | 665 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 665 insertions(+) create mode 100755 tools/ucl/src/ucl_swd.ch (limited to 'tools/ucl/src/ucl_swd.ch') diff --git a/tools/ucl/src/ucl_swd.ch b/tools/ucl/src/ucl_swd.ch new file mode 100755 index 0000000000..e40b4a4662 --- /dev/null +++ b/tools/ucl/src/ucl_swd.ch @@ -0,0 +1,665 @@ +/* ucl_swd.c -- sliding window dictionary + + This file is part of the UCL data compression library. + + Copyright (C) 1996-2002 Markus Franz Xaver Johannes Oberhumer + All Rights Reserved. + + The UCL 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 UCL 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 UCL library; see the file COPYING. + If not, write to the Free Software Foundation, Inc., + 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + + Markus F.X.J. Oberhumer + + */ + + +#if (UCL_UINT_MAX < UCL_0xffffffffL) +# error "UCL_UINT_MAX" +#endif + + +/*********************************************************************** +// +************************************************************************/ + +#ifndef SWD_N +# define SWD_N N +#endif +#ifndef SWD_F +# define SWD_F F +#endif +#ifndef SWD_THRESHOLD +# define SWD_THRESHOLD THRESHOLD +#endif + +/* unsigned type for dictionary access - don't waste memory here */ +#if (SWD_N + SWD_F + SWD_F < USHRT_MAX) + typedef unsigned short swd_uint; +# define SWD_UINT_MAX USHRT_MAX +#else + typedef ucl_uint swd_uint; +# define SWD_UINT_MAX UCL_UINT_MAX +#endif +#define SWD_UINT(x) ((swd_uint)(x)) + + +#ifndef SWD_HSIZE +# define SWD_HSIZE 16384 +#endif +#ifndef SWD_MAX_CHAIN +# define SWD_MAX_CHAIN 2048 +#endif + +#if !defined(HEAD3) +#if 1 +# define HEAD3(b,p) \ + (((0x9f5f*(((((ucl_uint32)b[p]<<5)^b[p+1])<<5)^b[p+2]))>>5) & (SWD_HSIZE-1)) +#else +# define HEAD3(b,p) \ + (((0x9f5f*(((((ucl_uint32)b[p+2]<<5)^b[p+1])<<5)^b[p]))>>5) & (SWD_HSIZE-1)) +#endif +#endif + +#if (SWD_THRESHOLD == 1) && !defined(HEAD2) +# if 1 && defined(UCL_UNALIGNED_OK_2) +# define HEAD2(b,p) (* (const ucl_ushortp) &(b[p])) +# else +# define HEAD2(b,p) (b[p] ^ ((unsigned)b[p+1]<<8)) +# endif +# define NIL2 SWD_UINT_MAX +#endif + + +#if defined(__UCL_CHECKER) + /* malloc arrays of the exact size to detect any overrun */ +# ifndef SWD_USE_MALLOC +# define SWD_USE_MALLOC +# endif +#endif + + +typedef struct +{ +/* public - "built-in" */ + ucl_uint n; + ucl_uint f; + ucl_uint threshold; + +/* public - configuration */ + ucl_uint max_chain; + ucl_uint nice_length; + ucl_bool use_best_off; + ucl_uint lazy_insert; + +/* public - output */ + ucl_uint m_len; + ucl_uint m_off; + ucl_uint look; + int b_char; +#if defined(SWD_BEST_OFF) + ucl_uint best_off[ SWD_BEST_OFF ]; +#endif + +/* semi public */ + UCL_COMPRESS_T *c; + ucl_uint m_pos; +#if defined(SWD_BEST_OFF) + ucl_uint best_pos[ SWD_BEST_OFF ]; +#endif + +/* private */ + const ucl_byte *dict; + const ucl_byte *dict_end; + ucl_uint dict_len; + +/* private */ + ucl_uint ip; /* input pointer (lookahead) */ + ucl_uint bp; /* buffer pointer */ + ucl_uint rp; /* remove pointer */ + ucl_uint b_size; + + unsigned char *b_wrap; + + ucl_uint node_count; + ucl_uint first_rp; + +#if defined(SWD_USE_MALLOC) + unsigned char *b; + swd_uint *head3; + swd_uint *succ3; + swd_uint *best3; + swd_uint *llen3; +#ifdef HEAD2 + swd_uint *head2; +#endif +#else + unsigned char b [ SWD_N + SWD_F + SWD_F ]; + swd_uint head3 [ SWD_HSIZE ]; + swd_uint succ3 [ SWD_N + SWD_F ]; + swd_uint best3 [ SWD_N + SWD_F ]; + swd_uint llen3 [ SWD_HSIZE ]; +#ifdef HEAD2 + swd_uint head2 [ UCL_UINT32_C(65536) ]; +#endif +#endif +} +ucl_swd_t; + + +/* Access macro for head3. + * head3[key] may be uninitialized if the list is emtpy, + * but then its value will never be used. + */ +#if defined(__UCL_CHECKER) +# define s_head3(s,key) \ + ((s->llen3[key] == 0) ? SWD_UINT_MAX : s->head3[key]) +#else +# define s_head3(s,key) s->head3[key] +#endif + + +/*********************************************************************** +// +************************************************************************/ + +static +void swd_initdict(ucl_swd_t *s, const ucl_byte *dict, ucl_uint dict_len) +{ + s->dict = s->dict_end = NULL; + s->dict_len = 0; + + if (!dict || dict_len <= 0) + return; + if (dict_len > s->n) + { + dict += dict_len - s->n; + dict_len = s->n; + } + + s->dict = dict; + s->dict_len = dict_len; + s->dict_end = dict + dict_len; + ucl_memcpy(s->b,dict,dict_len); + s->ip = dict_len; +} + + +static +void swd_insertdict(ucl_swd_t *s, ucl_uint node, ucl_uint len) +{ + ucl_uint key; + + s->node_count = s->n - len; + s->first_rp = node; + + while (len-- > 0) + { + key = HEAD3(s->b,node); + s->succ3[node] = s_head3(s,key); + s->head3[key] = SWD_UINT(node); + s->best3[node] = SWD_UINT(s->f + 1); + s->llen3[key]++; + assert(s->llen3[key] <= s->n); + +#ifdef HEAD2 + key = HEAD2(s->b,node); + s->head2[key] = SWD_UINT(node); +#endif + + node++; + } +} + + +/*********************************************************************** +// +************************************************************************/ + +static +int swd_init(ucl_swd_t *s, const ucl_byte *dict, ucl_uint dict_len) +{ + ucl_uint i = 0; + int c = 0; + + if (s->n == 0) + s->n = SWD_N; + if (s->f == 0) + s->f = SWD_F; + s->threshold = SWD_THRESHOLD; + if (s->n > SWD_N || s->f > SWD_F) + return UCL_E_INVALID_ARGUMENT; + +#if defined(SWD_USE_MALLOC) + s->b = (unsigned char *) ucl_alloc(s->n + s->f + s->f, 1); + s->head3 = (swd_uint *) ucl_alloc(SWD_HSIZE, sizeof(*s->head3)); + s->succ3 = (swd_uint *) ucl_alloc(s->n + s->f, sizeof(*s->succ3)); + s->best3 = (swd_uint *) ucl_alloc(s->n + s->f, sizeof(*s->best3)); + s->llen3 = (swd_uint *) ucl_alloc(SWD_HSIZE, sizeof(*s->llen3)); + if (!s->b || !s->head3 || !s->succ3 || !s->best3 || !s->llen3) + return UCL_E_OUT_OF_MEMORY; +#ifdef HEAD2 + s->head2 = (swd_uint *) ucl_alloc(UCL_UINT32_C(65536), sizeof(*s->head2)); + if (!s->head2) + return UCL_E_OUT_OF_MEMORY; +#endif +#endif + + /* defaults */ + s->max_chain = SWD_MAX_CHAIN; + s->nice_length = s->f; + s->use_best_off = 0; + s->lazy_insert = 0; + + s->b_size = s->n + s->f; + if (s->b_size + s->f >= SWD_UINT_MAX) + return UCL_E_ERROR; + s->b_wrap = s->b + s->b_size; + s->node_count = s->n; + + ucl_memset(s->llen3, 0, sizeof(s->llen3[0]) * SWD_HSIZE); +#ifdef HEAD2 +#if 1 + ucl_memset(s->head2, 0xff, sizeof(s->head2[0]) * UCL_UINT32_C(65536)); + assert(s->head2[0] == NIL2); +#else + for (i = 0; i < UCL_UINT32_C(65536); i++) + s->head2[i] = NIL2; +#endif +#endif + + s->ip = 0; + swd_initdict(s,dict,dict_len); + s->bp = s->ip; + s->first_rp = s->ip; + + assert(s->ip + s->f <= s->b_size); +#if 1 + s->look = (ucl_uint) (s->c->in_end - s->c->ip); + if (s->look > 0) + { + if (s->look > s->f) + s->look = s->f; + ucl_memcpy(&s->b[s->ip],s->c->ip,s->look); + s->c->ip += s->look; + s->ip += s->look; + } +#else + s->look = 0; + while (s->look < s->f) + { + if ((c = getbyte(*(s->c))) < 0) + break; + s->b[s->ip] = UCL_BYTE(c); + s->ip++; + s->look++; + } +#endif + if (s->ip == s->b_size) + s->ip = 0; + + if (s->look >= 2 && s->dict_len > 0) + swd_insertdict(s,0,s->dict_len); + + s->rp = s->first_rp; + if (s->rp >= s->node_count) + s->rp -= s->node_count; + else + s->rp += s->b_size - s->node_count; + +#if defined(__UCL_CHECKER) + /* initialize memory for the first few HEAD3 (if s->ip is not far + * enough ahead to do this job for us). The value doesn't matter. */ + if (s->look < 3) + ucl_memset(&s->b[s->bp+s->look],0,3); +#endif + + UCL_UNUSED(i); + UCL_UNUSED(c); + return UCL_E_OK; +} + + +static +void swd_exit(ucl_swd_t *s) +{ +#if defined(SWD_USE_MALLOC) + /* free in reverse order of allocations */ +#ifdef HEAD2 + ucl_free(s->head2); s->head2 = NULL; +#endif + ucl_free(s->llen3); s->llen3 = NULL; + ucl_free(s->best3); s->best3 = NULL; + ucl_free(s->succ3); s->succ3 = NULL; + ucl_free(s->head3); s->head3 = NULL; + ucl_free(s->b); s->b = NULL; +#else + UCL_UNUSED(s); +#endif +} + + +#define swd_pos2off(s,pos) \ + (s->bp > (pos) ? s->bp - (pos) : s->b_size - ((pos) - s->bp)) + + +/*********************************************************************** +// +************************************************************************/ + +static __inline__ +void swd_getbyte(ucl_swd_t *s) +{ + int c; + + if ((c = getbyte(*(s->c))) < 0) + { + if (s->look > 0) + --s->look; +#if defined(__UCL_CHECKER) + /* initialize memory - value doesn't matter */ + s->b[s->ip] = 0; + if (s->ip < s->f) + s->b_wrap[s->ip] = 0; +#endif + } + else + { + s->b[s->ip] = UCL_BYTE(c); + if (s->ip < s->f) + s->b_wrap[s->ip] = UCL_BYTE(c); + } + if (++s->ip == s->b_size) + s->ip = 0; + if (++s->bp == s->b_size) + s->bp = 0; + if (++s->rp == s->b_size) + s->rp = 0; +} + + +/*********************************************************************** +// remove node from lists +************************************************************************/ + +static __inline__ +void swd_remove_node(ucl_swd_t *s, ucl_uint node) +{ + if (s->node_count == 0) + { + ucl_uint key; + +#ifdef UCL_DEBUG + if (s->first_rp != UCL_UINT_MAX) + { + if (node != s->first_rp) + printf("Remove %5d: %5d %5d %5d %5d %6d %6d\n", + node, s->rp, s->ip, s->bp, s->first_rp, + s->ip - node, s->ip - s->bp); + assert(node == s->first_rp); + s->first_rp = UCL_UINT_MAX; + } +#endif + + 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 ((ucl_uint) s->head2[key] == node) + s->head2[key] = NIL2; +#endif + } + else + --s->node_count; +} + + +/*********************************************************************** +// +************************************************************************/ + +static +void swd_accept(ucl_swd_t *s, ucl_uint n) +{ + assert(n <= s->look); + + if (n > 0) do + { + ucl_uint key; + + swd_remove_node(s,s->rp); + + /* add bp into HEAD3 */ + key = HEAD3(s->b,s->bp); + s->succ3[s->bp] = s_head3(s,key); + s->head3[key] = SWD_UINT(s->bp); + s->best3[s->bp] = SWD_UINT(s->f + 1); + s->llen3[key]++; + assert(s->llen3[key] <= s->n); + +#ifdef HEAD2 + /* add bp into HEAD2 */ + key = HEAD2(s->b,s->bp); + s->head2[key] = SWD_UINT(s->bp); +#endif + + swd_getbyte(s); + } while (--n > 0); +} + + +/*********************************************************************** +// +************************************************************************/ + +static +void swd_search(ucl_swd_t *s, ucl_uint node, ucl_uint cnt) +{ +#if 0 && defined(__GNUC__) && defined(__i386__) + register const unsigned char *p1 __asm__("%edi"); + register const unsigned char *p2 __asm__("%esi"); + register const unsigned char *px __asm__("%edx"); +#else + const unsigned char *p1; + const unsigned char *p2; + const unsigned char *px; +#endif + ucl_uint m_len = s->m_len; + const unsigned char * b = s->b; + const unsigned char * bp = s->b + s->bp; + const unsigned char * 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 ( +#if 1 + p2[m_len - 1] == scan_end1 && + p2[m_len] == p1[m_len] && +#endif + p2[0] == p1[0] && + p2[1] == p1[1]) + { + ucl_uint i; + assert(ucl_memcmp(bp,&b[node],3) == 0); + +#if 0 && defined(UCL_UNALIGNED_OK_4) + p1 += 3; p2 += 3; + while (p1 < px && * (const ucl_uint32p) p1 == * (const ucl_uint32p) p2) + p1 += 4, p2 += 4; + while (p1 < px && *p1 == *p2) + p1 += 1, p2 += 1; +#else + p1 += 2; p2 += 2; + do {} while (++p1 < px && *p1 == *++p2); +#endif + i = p1 - bp; + +#ifdef UCL_DEBUG + if (ucl_memcmp(bp,&b[node],i) != 0) + printf("%5ld %5ld %02x%02x %02x%02x\n", + (long)s->bp, (long) node, + bp[0], bp[1], b[node], b[node+1]); +#endif + assert(ucl_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 >= s->nice_length) + return; + if (m_len > (ucl_uint) s->best3[node]) + return; + scan_end1 = bp[m_len - 1]; + } + } + } +} + + +/*********************************************************************** +// +************************************************************************/ + +#ifdef HEAD2 + +static +ucl_bool swd_search2(ucl_swd_t *s) +{ + ucl_uint key; + + assert(s->look >= 2); + assert(s->m_len > 0); + + key = s->head2[ HEAD2(s->b,s->bp) ]; + if (key == NIL2) + return 0; +#ifdef UCL_DEBUG + if (ucl_memcmp(&s->b[s->bp],&s->b[key],2) != 0) + printf("%5ld %5ld %02x%02x %02x%02x\n", (long)s->bp, (long)key, + s->b[s->bp], s->b[s->bp+1], s->b[key], s->b[key+1]); +#endif + assert(ucl_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(ucl_swd_t *s) +{ + ucl_uint key; + ucl_uint cnt, node; + ucl_uint 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_head3(s,key); + cnt = s->llen3[key]++; + assert(s->llen3[key] <= s->n + s->f); + if (cnt > s->max_chain && s->max_chain > 0) + cnt = s->max_chain; + s->head3[key] = SWD_UINT(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_UINT(s->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] = SWD_UINT(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] = SWD_UINT(s->bp); +#endif +} + + +#undef HEAD3 +#undef HEAD2 +#undef s_head3 + + +/* +vi:ts=4:et +*/ + -- cgit v1.2.3