Imported Upstream version 2.03upstream/2.03

1 files changed, 657 insertions, 0 deletions

diff --git a/src/lzo1a.c b/src/lzo1a.c
new file mode 100644
index 0000000..c571359
--- /dev/null
+++ b/src/lzo1a.c
@@ -0,0 +1,657 @@
+/* lzo1a.c -- implementation of the LZO1A 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 "lzo_conf.h"
+#include "lzo/lzo1a.h"
+
+
+/***********************************************************************
+// The next two defines can be changed to customize LZO1A.
+// The default version is LZO1A-5/1.
+************************************************************************/
+
+/* run bits (3 - 5) - the compressor and the decompressor
+ * must use the same value. */
+#if !defined(RBITS)
+#  define RBITS     5
+#endif
+
+/* compression level (1 - 9) - this only affects the compressor.
+ * 1 is fastest, 9 is best compression ratio
+ */
+#if !defined(CLEVEL)
+#  define CLEVEL    1           /* fastest by default */
+#endif
+
+
+/* Collect statistics */
+#if 0 && !defined(LZO_COLLECT_STATS)
+#  define LZO_COLLECT_STATS
+#endif
+
+
+/***********************************************************************
+// You should not have to change anything below this line.
+************************************************************************/
+
+/* check configuration */
+#if (RBITS < 3 || RBITS > 5)
+#  error "invalid RBITS"
+#endif
+#if (CLEVEL < 1 || CLEVEL > 9)
+#  error "invalid CLEVEL"
+#endif
+
+
+/***********************************************************************
+// internal configuration
+// all of these affect compression only
+************************************************************************/
+
+/* choose the hashing strategy */
+#ifndef LZO_HASH
+#define LZO_HASH    LZO_HASH_LZO_INCREMENTAL_A
+#endif
+#define D_INDEX1(d,p)       d = DM(DMUL(0x21,DX2(p,5,5)) >> 5)
+#define D_INDEX2(d,p)       d = d ^ D_MASK
+
+#include "lzo1a_de.h"
+#include "stats1a.h"
+
+
+/* check other constants */
+#if (LBITS < 5 || LBITS > 8)
+#  error "invalid LBITS"
+#endif
+
+
+#if defined(LZO_COLLECT_STATS)
+   static lzo1a_stats_t lzo_statistics;
+   lzo1a_stats_t *lzo1a_stats = &lzo_statistics;
+#  define lzo_stats lzo1a_stats
+#endif
+
+
+/***********************************************************************
+// get algorithm info, return memory required for compression
+************************************************************************/
+
+LZO_EXTERN(lzo_uint) lzo1a_info ( int *rbits, int *clevel );
+
+LZO_PUBLIC(lzo_uint)
+lzo1a_info ( int *rbits, int *clevel )
+{
+    if (rbits)
+        *rbits = RBITS;
+    if (clevel)
+        *clevel = CLEVEL;
+    return D_SIZE * lzo_sizeof(lzo_bytep);
+}
+
+
+/***********************************************************************
+// LZO1A decompress a block of data.
+//
+// Could be easily translated into assembly code.
+************************************************************************/
+
+LZO_PUBLIC(int)
+lzo1a_decompress ( const lzo_bytep in , lzo_uint  in_len,
+                         lzo_bytep out, lzo_uintp out_len,
+                         lzo_voidp wrkmem )
+{
+    register lzo_bytep op;
+    register const lzo_bytep ip;
+    register lzo_uint t;
+    register const lzo_bytep m_pos;
+    const lzo_bytep const ip_end = in + in_len;
+
+    LZO_UNUSED(wrkmem);
+
+    op = out;
+    ip = in;
+    while (ip < ip_end)
+    {
+        t = *ip++;      /* get marker */
+        LZO_STATS(lzo_stats->marker[t]++);
+
+        if (t == 0)             /* a R0 literal run */
+        {
+            t = *ip++;
+            if (t >= R0FAST - R0MIN)            /* a long R0 run */
+            {
+                t -= R0FAST - R0MIN;
+                if (t == 0)
+                    t = R0FAST;
+                else
+                {
+#if 0
+                    t = 256u << ((unsigned) t);
+#else
+                    /* help the optimizer */
+                    lzo_uint tt = 256;
+                    do tt <<= 1; while (--t > 0);
+                    t = tt;
+#endif
+                }
+                MEMCPY8_DS(op,ip,t);
+                continue;
+            }
+            t += R0MIN;
+            goto literal;
+        }
+        else if (t < R0MIN)     /* a short literal run */
+        {
+literal:
+            MEMCPY_DS(op,ip,t);
+
+        /* after a literal a match must follow */
+            while (ip < ip_end)
+            {
+                t = *ip++;          /* get R1 marker */
+                if (t >= R0MIN)
+                    goto match;
+
+            /* R1 match - a context sensitive 3 byte match + 1 byte literal */
+                assert((t & OMASK) == t);
+                m_pos = op - MIN_OFFSET;
+                m_pos -= t | (((lzo_uint) *ip++) << OBITS);
+                assert(m_pos >= out); assert(m_pos < op);
+                *op++ = *m_pos++;
+                *op++ = *m_pos++;
+                *op++ = *m_pos++;
+                *op++ = *ip++;
+            }
+        }
+        else                    /* a match */
+        {
+match:
+            /* get match offset */
+            m_pos = op - MIN_OFFSET;
+            m_pos -= (t & OMASK) | (((lzo_uint) *ip++) << OBITS);
+            assert(m_pos >= out); assert(m_pos < op);
+
+            /* get match len */
+            if (t < ((MSIZE - 1) << OBITS))         /* a short match */
+            {
+                t >>= OBITS;
+                *op++ = *m_pos++;
+                *op++ = *m_pos++;
+                MEMCPY_DS(op,m_pos,t);
+            }
+            else                                     /* a long match */
+            {
+#if (LBITS < 8)
+                t = (MIN_MATCH_LONG - THRESHOLD) + ((lzo_uint)(*ip++) & LMASK);
+#else
+                t = (MIN_MATCH_LONG - THRESHOLD) + (lzo_uint)(*ip++);
+#endif
+                *op++ = *m_pos++;
+                *op++ = *m_pos++;
+                MEMCPY_DS(op,m_pos,t);
+#if (LBITS < 8)
+                /* a very short literal following a long match */
+                t = ip[-1] >> LBITS;
+                if (t) do
+                    *op++ = *ip++;
+                while (--t);
+#endif
+            }
+        }
+    }
+
+    *out_len = pd(op, out);
+
+    /* the next line is the only check in the decompressor */
+    return (ip == ip_end ? LZO_E_OK :
+           (ip < ip_end  ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
+}
+
+
+
+/***********************************************************************
+// LZO1A compress a block of data.
+//
+// I apologize for the spaghetti code, but it really helps the optimizer.
+************************************************************************/
+
+#include "lzo1a_cr.ch"
+
+static int
+do_compress    ( const lzo_bytep in , lzo_uint  in_len,
+                       lzo_bytep out, lzo_uintp out_len,
+                       lzo_voidp wrkmem )
+{
+    register const lzo_bytep ip;
+#if defined(__LZO_HASH_INCREMENTAL)
+    lzo_xint dv;
+#endif
+    const lzo_bytep m_pos;
+    lzo_bytep op;
+    const lzo_bytep const ip_end = in+in_len - DVAL_LEN - MIN_MATCH_LONG;
+    const lzo_bytep const in_end = in+in_len - DVAL_LEN;
+    const lzo_bytep ii;
+    lzo_dict_p const dict = (lzo_dict_p) wrkmem;
+    const lzo_bytep r1 = ip_end;    /* pointer for R1 match (none yet) */
+#if (LBITS < 8)
+    const lzo_bytep im = ip_end;    /* pointer to last match start */
+#endif
+
+#if !defined(NDEBUG)
+    const lzo_bytep m_pos_sav;
+#endif
+
+    op = out;
+    ip = in;
+    ii = ip;            /* point to start of current literal run */
+
+    /* init dictionary */
+#if defined(LZO_DETERMINISTIC)
+    BZERO8_PTR(wrkmem,sizeof(lzo_dict_t),D_SIZE);
+#endif
+
+    DVAL_FIRST(dv,ip); UPDATE_D(dict,0,dv,ip,in); ip++;
+    DVAL_NEXT(dv,ip);
+
+    do {
+        lzo_uint m_off;
+        lzo_uint dindex;
+
+        DINDEX1(dindex,ip);
+        GINDEX(m_pos,m_off,dict,dindex,in);
+        if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,MAX_OFFSET))
+            goto literal;
+        if (m_pos[0] == ip[0] && m_pos[1] == ip[1] && m_pos[2] == ip[2])
+            goto match;
+        DINDEX2(dindex,ip);
+        GINDEX(m_pos,m_off,dict,dindex,in);
+        if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,MAX_OFFSET))
+            goto literal;
+        if (m_pos[0] == ip[0] && m_pos[1] == ip[1] && m_pos[2] == ip[2])
+            goto match;
+        goto literal;
+
+literal:
+        UPDATE_I(dict,0,dindex,ip,in);
+        if (++ip >= ip_end)
+            break;
+        continue;
+
+match:
+        UPDATE_I(dict,0,dindex,ip,in);
+#if !defined(NDEBUG) && defined(LZO_DICT_USE_PTR)
+        assert(m_pos == NULL || m_pos >= in);
+        m_pos_sav = m_pos;
+#endif
+        m_pos += 3;
+        {
+    /* we have found a match (of at least length 3) */
+
+#if !defined(NDEBUG) && !defined(LZO_DICT_USE_PTR)
+            assert((m_pos_sav = ip - m_off) == (m_pos - 3));
+#endif
+
+            assert(m_pos >= in);
+            assert(ip < ip_end);
+
+            /* 1) store the current literal run */
+            if (pd(ip,ii) > 0)
+            {
+                lzo_uint t = pd(ip,ii);
+
+                if (ip - r1 == MIN_MATCH + 1)
+                {
+                /* Code a context sensitive R1 match.
+                 * This is tricky and somewhat difficult to explain:
+                 * multiplex a literal run of length 1 into the previous
+                 * short match of length MIN_MATCH.
+                 * The key idea is:
+                 *  - after a short run a match MUST follow
+                 *  - therefore the value m = 000 in the mmmooooo marker is free
+                 *  - use 000ooooo to indicate a MIN_MATCH match (this
+                 *    is already coded) plus a 1 byte literal
+                 */
+                    assert(t == 1);
+                    /* modify marker byte */
+                    assert((op[-2] >> OBITS) == (MIN_MATCH - THRESHOLD));
+                    op[-2] &= OMASK;
+                    assert((op[-2] >> OBITS) == 0);
+                    /* copy 1 literal */
+                    *op++ = *ii;
+                    LZO_STATS(lzo_stats->r1_matches++);
+                    r1 = ip;                /* set new R1 pointer */
+                }
+                else if (t < R0MIN)
+                {
+                    /* inline the copying of a short run */
+#if (LBITS < 8)
+                    if (t < (1 << (8-LBITS)) && ii - im >= MIN_MATCH_LONG)
+                    {
+                    /* Code a very short literal run into the
+                     * previous long match length byte.
+                     */
+                        LZO_STATS(lzo_stats->lit_runs_after_long_match++);
+                        LZO_STATS(lzo_stats->lit_run_after_long_match[t]++);
+                        assert(ii - im <= MAX_MATCH_LONG);
+                        assert((op[-1] >> LBITS) == 0);
+                        op[-1] |= t << LBITS;
+                        MEMCPY_DS(op, ii, t);
+                    }
+                    else
+#endif
+                    {
+                        LZO_STATS(lzo_stats->lit_runs++);
+                        LZO_STATS(lzo_stats->lit_run[t]++);
+                        *op++ = LZO_BYTE(t);
+                        MEMCPY_DS(op, ii, t);
+                        r1 = ip;                /* set new R1 pointer */
+                    }
+                }
+                else if (t < R0FAST)
+                {
+                    /* inline the copying of a short R0 run */
+                    LZO_STATS(lzo_stats->r0short_runs++);
+                    *op++ = 0; *op++ = LZO_BYTE(t - R0MIN);
+                    MEMCPY_DS(op, ii, t);
+                    r1 = ip;                /* set new R1 pointer */
+                }
+                else
+                    op = store_run(op,ii,t);
+            }
+#if (LBITS < 8)
+            im = ip;
+#endif
+
+
+            /* 2) compute match len */
+            ii = ip;        /* point to start of current match */
+
+            /* we already matched MIN_MATCH bytes,
+             * m_pos also already advanced MIN_MATCH bytes */
+            ip += MIN_MATCH;
+            assert(m_pos < ip);
+
+            /* try to match another MIN_MATCH_LONG - MIN_MATCH bytes
+             * to see if we get a long match */
+
+#define PS  *m_pos++ != *ip++
+
+#if (MIN_MATCH_LONG - MIN_MATCH == 2)                   /* MBITS == 2 */
+            if (PS || PS)
+#elif (MIN_MATCH_LONG - MIN_MATCH == 6)                 /* MBITS == 3 */
+            if (PS || PS || PS || PS || PS || PS)
+#elif (MIN_MATCH_LONG - MIN_MATCH == 14)                /* MBITS == 4 */
+            if (PS || PS || PS || PS || PS || PS || PS ||
+                PS || PS || PS || PS || PS || PS || PS)
+#elif (MIN_MATCH_LONG - MIN_MATCH == 30)                /* MBITS == 5 */
+            if (PS || PS || PS || PS || PS || PS || PS || PS ||
+                PS || PS || PS || PS || PS || PS || PS || PS ||
+                PS || PS || PS || PS || PS || PS || PS || PS ||
+                PS || PS || PS || PS || PS || PS)
+#else
+#  error "MBITS not yet implemented"
+#endif
+            {
+            /* we've found a short match */
+                lzo_uint m_len;
+
+            /* 2a) compute match parameters */
+                    assert(ip-m_pos == (int)m_off);
+                --ip;   /* ran one too far, point back to non-match */
+                m_len = pd(ip, ii);
+                    assert(m_len >= MIN_MATCH_SHORT);
+                    assert(m_len <= MAX_MATCH_SHORT);
+                    assert(m_off >= MIN_OFFSET);
+                    assert(m_off <= MAX_OFFSET);
+                    assert(ii-m_off == m_pos_sav);
+                    assert(lzo_memcmp(m_pos_sav,ii,m_len) == 0);
+                m_off -= MIN_OFFSET;
+
+            /* 2b) code a short match */
+                /* code short match len + low offset bits */
+                *op++ = LZO_BYTE(((m_len - THRESHOLD) << OBITS) |
+                                 (m_off & OMASK));
+                /* code high offset bits */
+                *op++ = LZO_BYTE(m_off >> OBITS);
+
+
+#if defined(LZO_COLLECT_STATS)
+                lzo_stats->short_matches++;
+                lzo_stats->short_match[m_len]++;
+                if (m_off < OSIZE)
+                    lzo_stats->short_match_offset_osize[m_len]++;
+                if (m_off < 256)
+                    lzo_stats->short_match_offset_256[m_len]++;
+                if (m_off < 1024)
+                    lzo_stats->short_match_offset_1024[m_len]++;
+#endif
+
+
+            /* 2c) Insert phrases (beginning with ii+1) into the dictionary. */
+
+#define SI      /* nothing */
+#define DI      ++ii; DVAL_NEXT(dv,ii); UPDATE_D(dict,0,dv,ii,in);
+#define XI      assert(ii < ip); ii = ip; DVAL_FIRST(dv,(ip));
+
+#if (CLEVEL == 9) || (CLEVEL >= 7 && MBITS <= 4) || (CLEVEL >= 5 && MBITS <= 3)
+            /* Insert the whole match (ii+1)..(ip-1) into dictionary.  */
+                ++ii;
+                do {
+                    DVAL_NEXT(dv,ii);
+                    UPDATE_D(dict,0,dv,ii,in);
+                } while (++ii < ip);
+                DVAL_NEXT(dv,ii);
+                assert(ii == ip);
+                DVAL_ASSERT(dv,ip);
+#elif (CLEVEL >= 3)
+                SI   DI DI   XI
+#elif (CLEVEL >= 2)
+                SI   DI      XI
+#else
+                             XI
+#endif
+
+            }
+            else
+            {
+            /* we've found a long match - see how far we can still go */
+                const lzo_bytep end;
+                lzo_uint m_len;
+
+                assert(ip <= in_end);
+                assert(ii == ip - MIN_MATCH_LONG);
+
+                if (pd(in_end,ip) <= (MAX_MATCH_LONG - MIN_MATCH_LONG))
+                    end = in_end;
+                else
+                {
+                    end = ip + (MAX_MATCH_LONG - MIN_MATCH_LONG);
+                    assert(end < in_end);
+                }
+
+                while (ip < end  &&  *m_pos == *ip)
+                    m_pos++, ip++;
+                assert(ip <= in_end);
+
+            /* 2a) compute match parameters */
+                m_len = pd(ip, ii);
+                    assert(m_len >= MIN_MATCH_LONG);
+                    assert(m_len <= MAX_MATCH_LONG);
+                    assert(m_off >= MIN_OFFSET);
+                    assert(m_off <= MAX_OFFSET);
+                    assert(ii-m_off == m_pos_sav);
+                    assert(lzo_memcmp(m_pos_sav,ii,m_len) == 0);
+                    assert(pd(ip,m_pos) == m_off);
+                m_off -= MIN_OFFSET;
+
+            /* 2b) code the long match */
+                /* code long match flag + low offset bits */
+                *op++ = LZO_BYTE(((MSIZE - 1) << OBITS) | (m_off & OMASK));
+                /* code high offset bits */
+                *op++ = LZO_BYTE(m_off >> OBITS);
+                /* code match len */
+                *op++ = LZO_BYTE(m_len - MIN_MATCH_LONG);
+
+
+#if defined(LZO_COLLECT_STATS)
+                lzo_stats->long_matches++;
+                lzo_stats->long_match[m_len]++;
+#endif
+
+
+            /* 2c) Insert phrases (beginning with ii+1) into the dictionary. */
+#if (CLEVEL == 9)
+            /* Insert the whole match (ii+1)..(ip-1) into dictionary.  */
+            /* This is not recommended because it is slow. */
+                ++ii;
+                do {
+                    DVAL_NEXT(dv,ii);
+                    UPDATE_D(dict,0,dv,ii,in);
+                } while (++ii < ip);
+                DVAL_NEXT(dv,ii);
+                assert(ii == ip);
+                DVAL_ASSERT(dv,ip);
+#elif (CLEVEL >= 8)
+                SI   DI DI DI DI DI DI DI DI   XI
+#elif (CLEVEL >= 7)
+                SI   DI DI DI DI DI DI DI      XI
+#elif (CLEVEL >= 6)
+                SI   DI DI DI DI DI DI         XI
+#elif (CLEVEL >= 5)
+                SI   DI DI DI DI               XI
+#elif (CLEVEL >= 4)
+                SI   DI DI DI                  XI
+#elif (CLEVEL >= 3)
+                SI   DI DI                     XI
+#elif (CLEVEL >= 2)
+                SI   DI                        XI
+#else
+                                               XI
+#endif
+            }
+
+            /* ii now points to the start of the next literal run */
+            assert(ii == ip);
+        }
+
+    } while (ip < ip_end);
+
+    assert(ip <= in_end);
+
+
+#if defined(LZO_RETURN_IF_NOT_COMPRESSIBLE)
+    /* return -1 if op == out to indicate that we
+     * couldn't compress and didn't copy anything.
+     */
+    if (op == out)
+    {
+        *out_len = 0;
+        return LZO_E_NOT_COMPRESSIBLE;
+    }
+#endif
+
+    /* store the final literal run */
+    if (pd(in_end+DVAL_LEN,ii) > 0)
+        op = store_run(op,ii,pd(in_end+DVAL_LEN,ii));
+
+    *out_len = pd(op, out);
+    return 0;               /* compression went ok */
+}
+
+
+/***********************************************************************
+// LZO1A compress public entry point.
+************************************************************************/
+
+LZO_PUBLIC(int)
+lzo1a_compress ( const lzo_bytep in , lzo_uint  in_len,
+                       lzo_bytep out, lzo_uintp out_len,
+                       lzo_voidp wrkmem )
+{
+    int r = LZO_E_OK;
+
+
+#if defined(LZO_COLLECT_STATS)
+    lzo_memset(lzo_stats,0,sizeof(*lzo_stats));
+    lzo_stats->rbits  = RBITS;
+    lzo_stats->clevel = CLEVEL;
+    lzo_stats->dbits  = DBITS;
+    lzo_stats->lbits  = LBITS;
+    lzo_stats->min_match_short = MIN_MATCH_SHORT;
+    lzo_stats->max_match_short = MAX_MATCH_SHORT;
+    lzo_stats->min_match_long  = MIN_MATCH_LONG;
+    lzo_stats->max_match_long  = MAX_MATCH_LONG;
+    lzo_stats->min_offset      = MIN_OFFSET;
+    lzo_stats->max_offset      = MAX_OFFSET;
+    lzo_stats->r0min  = R0MIN;
+    lzo_stats->r0fast = R0FAST;
+    lzo_stats->r0max  = R0MAX;
+    lzo_stats->in_len = in_len;
+#endif
+
+
+    /* don't try to compress a block that's too short */
+    if (in_len <= 0)
+        *out_len = 0;
+    else if (in_len <= MIN_MATCH_LONG + DVAL_LEN + 1)
+    {
+#if defined(LZO_RETURN_IF_NOT_COMPRESSIBLE)
+        r = LZO_E_NOT_COMPRESSIBLE;
+#else
+        *out_len = pd(store_run(out,in,in_len), out);
+#endif
+    }
+    else
+        r = do_compress(in,in_len,out,out_len,wrkmem);
+
+
+#if defined(LZO_COLLECT_STATS)
+    lzo_stats->short_matches -= lzo_stats->r1_matches;
+    lzo_stats->short_match[MIN_MATCH] -= lzo_stats->r1_matches;
+    lzo_stats->out_len = *out_len;
+#endif
+
+    return r;
+}
+
+
+/*
+vi:ts=4:et
+*/