1 /* lzo1f_d.ch -- implementation of the LZO1F decompression algorithm
3 This file is part of the LZO real-time data compression library.
5 Copyright (C) 1996-2015 Markus Franz Xaver Johannes Oberhumer
8 The LZO library is free software; you can redistribute it and/or
9 modify it under the terms of the GNU General Public License as
10 published by the Free Software Foundation; either version 2 of
11 the License, or (at your option) any later version.
13 The LZO library is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with the LZO library; see the file COPYING.
20 If not, write to the Free Software Foundation, Inc.,
21 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
23 Markus F.X.J. Oberhumer
24 <markus@oberhumer.com>
25 http://www.oberhumer.com/opensource/lzo/
32 /***********************************************************************
33 // decompress a block of data.
34 ************************************************************************/
37 DO_DECOMPRESS ( const lzo_bytep in , lzo_uint in_len,
38 lzo_bytep out, lzo_uintp out_len,
44 const lzo_bytep m_pos;
46 const lzo_bytep const ip_end = in + in_len;
47 #if defined(HAVE_ANY_OP)
48 lzo_bytep const op_end = out + *out_len;
58 while (TEST_IP_AND_TEST_OP)
78 assert(t > 0); NEED_OP(t); NEED_IP(t+1);
79 #if (LZO_OPT_UNALIGNED32)
84 op += 4; ip += 4; t -= 4;
86 if (t > 0) do *op++ = *ip++; while (--t > 0);
90 do *op++ = *ip++; while (--t > 0);
94 while (TEST_IP_AND_TEST_OP)
99 m_pos = op - 1 - 0x800;
100 m_pos -= (t >> 2) & 7;
102 TEST_LB(m_pos); NEED_OP(3);
103 *op++ = *m_pos++; *op++ = *m_pos++; *op++ = *m_pos++;
111 m_pos -= (t >> 2) & 7;
114 TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
134 #if (LZO_OPT_UNALIGNED16) && (LZO_ABI_LITTLE_ENDIAN)
135 m_pos -= UA_GET_LE16(ip) >> 2;
146 TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
147 #if (LZO_OPT_UNALIGNED32)
148 if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4)
151 op += 4; m_pos += 4; t -= 4 - (3 - 1);
154 op += 4; m_pos += 4; t -= 4;
156 if (t > 0) do *op++ = *m_pos++; while (--t > 0);
162 *op++ = *m_pos++; *op++ = *m_pos++;
163 do *op++ = *m_pos++; while (--t > 0);
171 assert(t > 0); NEED_OP(t); NEED_IP(t+1);
172 do *op++ = *ip++; while (--t > 0);
177 #if defined(HAVE_TEST_IP) || defined(HAVE_TEST_OP)
178 /* no EOF code was found */
179 *out_len = pd(op, out);
180 return LZO_E_EOF_NOT_FOUND;
185 *out_len = pd(op, out);
186 return (ip == ip_end ? LZO_E_OK :
187 (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
190 #if defined(HAVE_NEED_IP)
192 *out_len = pd(op, out);
193 return LZO_E_INPUT_OVERRUN;
196 #if defined(HAVE_NEED_OP)
198 *out_len = pd(op, out);
199 return LZO_E_OUTPUT_OVERRUN;
202 #if defined(LZO_TEST_OVERRUN_LOOKBEHIND)
204 *out_len = pd(op, out);
205 return LZO_E_LOOKBEHIND_OVERRUN;
210 /* vim:set ts=4 sw=4 et: */