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- /* lzo1b_cr.ch -- implementation of the LZO1B compression algorithm
-
- This file is part of the LZO real-time data compression library.
-
- Copyright (C) 1996 Markus Franz Xaver Johannes Oberhumer
-
- 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.,
- 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
- Markus F.X.J. Oberhumer
- markus.oberhumer@jk.uni-linz.ac.at
- */
-
-
- /* WARNING: this file should *not* be used by applications. It is
- part of the implementation of the library and is subject
- to change.
- */
-
-
-
- /***********************************************************************
- // store the current literal run
- ************************************************************************/
-
- assert(ip < ip_end);
- if (ip - ii > 0)
- {
- lzo_uint t = ip - ii;
-
- #if defined(LZO_HAVE_R1)
- if (ip == r1)
- {
- /* Code a context sensitive R1 match. */
- LZO_STATS(lzo_stats->literals += t);
- LZO_STATS(lzo_stats->r1_matches++);
- assert(t == 1);
- /* modify marker byte */
- assert((op[-2] >> M2O_BITS) == (M2_MARKER >> M2O_BITS));
- op[-2] &= M2O_MASK;
- assert((op[-2] >> M2O_BITS) == 0);
- /* copy 1 literal */
- *op++ = *ii++;
- r1 = ip + (M2_MIN_LEN + 1); /* set new R1 pointer */
- }
- else
- #endif
- if (t < R0MIN)
- {
- /* inline the copying of a short run */
- LZO_STATS(lzo_stats->literals += t);
- LZO_STATS(lzo_stats->lit_runs++);
- LZO_STATS(lzo_stats->lit_run[t]++);
- #if defined(LZO_HAVE_M3)
- if (t < LZO_SIZE(8-M3O_BITS) && op == m3)
- {
- /* Code a very short literal run into the low offset bits
- * of the previous M3/M4 match.
- */
- LZO_STATS(lzo_stats->lit_runs_after_m3_match++);
- LZO_STATS(lzo_stats->lit_run_after_m3_match[t]++);
- assert((m3[-2] >> M3O_BITS) == 0);
- m3[-2] |= LZO_BYTE(t << M3O_BITS);
- }
- else
- #endif
- {
- *op++ = LZO_BYTE(t);
- }
- MEMCPY_DS(op, ii, t);
- #if defined(LZO_HAVE_R1)
- r1 = ip + (M2_MIN_LEN + 1); /* set new R1 pointer */
- #endif
- }
- else if (t < R0FAST)
- {
- /* inline the copying of a short R0 run */
- LZO_STATS(lzo_stats->literals += t);
- LZO_STATS(lzo_stats->r0short_runs++);
- *op++ = 0; *op++ = LZO_BYTE(t - R0MIN);
- MEMCPY_DS(op, ii, t);
- #if defined(LZO_HAVE_R1)
- r1 = ip + (M2_MIN_LEN + 1); /* set new R1 pointer */
- #endif
- }
- else
- {
- op = STORE_RUN(op,ii,t);
- ii = ip;
- }
- }
-
-
- /* ii now points to the start of the current match */
- assert(ii == ip);
-
-
- /*
- vi:ts=4
- */
-