diff options
author | Denys Vlasenko <vda.linux@googlemail.com> | 2010-11-03 04:38:31 +0300 |
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committer | Denys Vlasenko <vda.linux@googlemail.com> | 2010-11-03 04:38:31 +0300 |
commit | 833d4e7f84f59099ee66eabfa3457ebb7d37eaa8 (patch) | |
tree | 3be84e1049707ce8077291065fe3689497c69b9c /archival/libarchive/lzo1x_c.c | |
parent | 5e9934028aa030312a1a2e2e32d5ceade8672beb (diff) |
rename archival/libunarchive -> archival/libarchive; move bz/ into it
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival/libarchive/lzo1x_c.c')
-rw-r--r-- | archival/libarchive/lzo1x_c.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/archival/libarchive/lzo1x_c.c b/archival/libarchive/lzo1x_c.c new file mode 100644 index 000000000..cc86f74b1 --- /dev/null +++ b/archival/libarchive/lzo1x_c.c @@ -0,0 +1,296 @@ +/* implementation of the LZO1[XY]-1 compression algorithm + + This file is part of the LZO real-time data compression library. + + Copyright (C) 1996..2008 Markus Franz Xaver Johannes Oberhumer + All Rights Reserved. + + Markus F.X.J. Oberhumer <markus@oberhumer.com> + http://www.oberhumer.com/opensource/lzo/ + + 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. + */ + +/*********************************************************************** +// compress a block of data. +************************************************************************/ +static NOINLINE unsigned +do_compress(const uint8_t* in, unsigned in_len, + uint8_t* out, unsigned* out_len, + void* wrkmem) +{ + register const uint8_t* ip; + uint8_t* op; + const uint8_t* const in_end = in + in_len; + const uint8_t* const ip_end = in + in_len - M2_MAX_LEN - 5; + const uint8_t* ii; + const void* *const dict = (const void**) wrkmem; + + op = out; + ip = in; + ii = ip; + + ip += 4; + for (;;) { + register const uint8_t* m_pos; + unsigned m_off; + unsigned m_len; + unsigned dindex; + + D_INDEX1(dindex,ip); + GINDEX(m_pos,m_off,dict,dindex,in); + if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,M4_MAX_OFFSET)) + goto literal; +#if 1 + if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3]) + goto try_match; + D_INDEX2(dindex,ip); +#endif + GINDEX(m_pos,m_off,dict,dindex,in); + if (LZO_CHECK_MPOS_NON_DET(m_pos,m_off,in,ip,M4_MAX_OFFSET)) + goto literal; + if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3]) + goto try_match; + goto literal; + + try_match: +#if 1 && defined(LZO_UNALIGNED_OK_2) + if (* (const lzo_ushortp) m_pos != * (const lzo_ushortp) ip) +#else + if (m_pos[0] != ip[0] || m_pos[1] != ip[1]) +#endif + { + } else { + if (m_pos[2] == ip[2]) { +#if 0 + if (m_off <= M2_MAX_OFFSET) + goto match; + if (lit <= 3) + goto match; + if (lit == 3) { /* better compression, but slower */ + assert(op - 2 > out); op[-2] |= (uint8_t)(3); + *op++ = *ii++; *op++ = *ii++; *op++ = *ii++; + goto code_match; + } + if (m_pos[3] == ip[3]) +#endif + goto match; + } + else { + /* still need a better way for finding M1 matches */ +#if 0 + /* a M1 match */ +#if 0 + if (m_off <= M1_MAX_OFFSET && lit > 0 && lit <= 3) +#else + if (m_off <= M1_MAX_OFFSET && lit == 3) +#endif + { + register unsigned t; + + t = lit; + assert(op - 2 > out); op[-2] |= (uint8_t)(t); + do *op++ = *ii++; while (--t > 0); + assert(ii == ip); + m_off -= 1; + *op++ = (uint8_t)(M1_MARKER | ((m_off & 3) << 2)); + *op++ = (uint8_t)(m_off >> 2); + ip += 2; + goto match_done; + } +#endif + } + } + + /* a literal */ + literal: + UPDATE_I(dict, 0, dindex, ip, in); + ++ip; + if (ip >= ip_end) + break; + continue; + + /* a match */ +match: + UPDATE_I(dict, 0, dindex, ip, in); + /* store current literal run */ + if (pd(ip, ii) > 0) { + register unsigned t = pd(ip, ii); + + if (t <= 3) { + assert(op - 2 > out); + op[-2] |= (uint8_t)(t); + } + else if (t <= 18) + *op++ = (uint8_t)(t - 3); + else { + register unsigned tt = t - 18; + + *op++ = 0; + while (tt > 255) { + tt -= 255; + *op++ = 0; + } + assert(tt > 0); + *op++ = (uint8_t)(tt); + } + do *op++ = *ii++; while (--t > 0); + } + + /* code the match */ + assert(ii == ip); + ip += 3; + if (m_pos[3] != *ip++ || m_pos[4] != *ip++ || m_pos[5] != *ip++ + || m_pos[6] != *ip++ || m_pos[7] != *ip++ || m_pos[8] != *ip++ +#ifdef LZO1Y + || m_pos[ 9] != *ip++ || m_pos[10] != *ip++ || m_pos[11] != *ip++ + || m_pos[12] != *ip++ || m_pos[13] != *ip++ || m_pos[14] != *ip++ +#endif + ) { + --ip; + m_len = pd(ip, ii); + assert(m_len >= 3); + assert(m_len <= M2_MAX_LEN); + + if (m_off <= M2_MAX_OFFSET) { + m_off -= 1; +#if defined(LZO1X) + *op++ = (uint8_t)(((m_len - 1) << 5) | ((m_off & 7) << 2)); + *op++ = (uint8_t)(m_off >> 3); +#elif defined(LZO1Y) + *op++ = (uint8_t)(((m_len + 1) << 4) | ((m_off & 3) << 2)); + *op++ = (uint8_t)(m_off >> 2); +#endif + } + else if (m_off <= M3_MAX_OFFSET) { + m_off -= 1; + *op++ = (uint8_t)(M3_MARKER | (m_len - 2)); + goto m3_m4_offset; + } else { +#if defined(LZO1X) + m_off -= 0x4000; + assert(m_off > 0); + assert(m_off <= 0x7fff); + *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11) | (m_len - 2)); + goto m3_m4_offset; +#elif defined(LZO1Y) + goto m4_match; +#endif + } + } + else { + { + const uint8_t* end = in_end; + const uint8_t* m = m_pos + M2_MAX_LEN + 1; + while (ip < end && *m == *ip) + m++, ip++; + m_len = pd(ip, ii); + } + assert(m_len > M2_MAX_LEN); + + if (m_off <= M3_MAX_OFFSET) { + m_off -= 1; + if (m_len <= 33) + *op++ = (uint8_t)(M3_MARKER | (m_len - 2)); + else { + m_len -= 33; + *op++ = M3_MARKER | 0; + goto m3_m4_len; + } + } else { +#if defined(LZO1Y) + m4_match: +#endif + m_off -= 0x4000; + assert(m_off > 0); + assert(m_off <= 0x7fff); + if (m_len <= M4_MAX_LEN) + *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11) | (m_len - 2)); + else { + m_len -= M4_MAX_LEN; + *op++ = (uint8_t)(M4_MARKER | ((m_off & 0x4000) >> 11)); + m3_m4_len: + while (m_len > 255) { + m_len -= 255; + *op++ = 0; + } + assert(m_len > 0); + *op++ = (uint8_t)(m_len); + } + } + m3_m4_offset: + *op++ = (uint8_t)((m_off & 63) << 2); + *op++ = (uint8_t)(m_off >> 6); + } +#if 0 + match_done: +#endif + ii = ip; + if (ip >= ip_end) + break; + } + + *out_len = pd(op, out); + return pd(in_end, ii); +} + +/*********************************************************************** +// public entry point +************************************************************************/ +int DO_COMPRESS(const uint8_t* in, unsigned in_len, + uint8_t* out, unsigned* out_len, + void* wrkmem) +{ + uint8_t* op = out; + unsigned t; + + if (in_len <= M2_MAX_LEN + 5) + t = in_len; + else { + t = do_compress(in,in_len,op,out_len,wrkmem); + op += *out_len; + } + + if (t > 0) { + const uint8_t* ii = in + in_len - t; + + if (op == out && t <= 238) + *op++ = (uint8_t)(17 + t); + else if (t <= 3) + op[-2] |= (uint8_t)(t); + else if (t <= 18) + *op++ = (uint8_t)(t - 3); + else { + unsigned tt = t - 18; + + *op++ = 0; + while (tt > 255) { + tt -= 255; + *op++ = 0; + } + assert(tt > 0); + *op++ = (uint8_t)(tt); + } + do *op++ = *ii++; while (--t > 0); + } + + *op++ = M4_MARKER | 1; + *op++ = 0; + *op++ = 0; + + *out_len = pd(op, out); + return 0; /*LZO_E_OK*/ +} |