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-rw-r--r--archival/libarchive/lzo1x_c.c296
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diff --git a/archival/libarchive/lzo1x_c.c b/archival/libarchive/lzo1x_c.c
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+/* 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*/
+}
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