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-rw-r--r--src/grt/fst/fastlz.c547
1 files changed, 547 insertions, 0 deletions
diff --git a/src/grt/fst/fastlz.c b/src/grt/fst/fastlz.c
new file mode 100644
index 000000000..50bf56a46
--- /dev/null
+++ b/src/grt/fst/fastlz.c
@@ -0,0 +1,547 @@
+/*
+ FastLZ - lightning-fast lossless compression library
+
+ Copyright (C) 2007 Ariya Hidayat (ariya@kde.org)
+ Copyright (C) 2006 Ariya Hidayat (ariya@kde.org)
+ Copyright (C) 2005 Ariya Hidayat (ariya@kde.org)
+
+ Permission is hereby granted, free of charge, to any person obtaining a copy
+ of this software and associated documentation files (the "Software"), to deal
+ in the Software without restriction, including without limitation the rights
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ copies of the Software, and to permit persons to whom the Software is
+ furnished to do so, subject to the following conditions:
+
+ The above copyright notice and this permission notice shall be included in
+ all copies or substantial portions of the Software.
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ THE SOFTWARE.
+*/
+
+#include "fastlz.h"
+
+#if !defined(FASTLZ__COMPRESSOR) && !defined(FASTLZ_DECOMPRESSOR)
+
+/*
+ * Always check for bound when decompressing.
+ * Generally it is best to leave it defined.
+ */
+#define FASTLZ_SAFE
+
+
+/*
+ * Give hints to the compiler for branch prediction optimization.
+ */
+#if defined(__GNUC__) && (__GNUC__ > 2)
+#define FASTLZ_EXPECT_CONDITIONAL(c) (__builtin_expect((c), 1))
+#define FASTLZ_UNEXPECT_CONDITIONAL(c) (__builtin_expect((c), 0))
+#else
+#define FASTLZ_EXPECT_CONDITIONAL(c) (c)
+#define FASTLZ_UNEXPECT_CONDITIONAL(c) (c)
+#endif
+
+/*
+ * Use inlined functions for supported systems.
+ */
+#if defined(__GNUC__) || defined(__DMC__) || defined(__POCC__) || defined(__WATCOMC__) || defined(__SUNPRO_C)
+#define FASTLZ_INLINE inline
+#elif defined(__BORLANDC__) || defined(_MSC_VER) || defined(__LCC__)
+#define FASTLZ_INLINE __inline
+#else
+#define FASTLZ_INLINE
+#endif
+
+/*
+ * Prevent accessing more than 8-bit at once, except on x86 architectures.
+ */
+#if !defined(FASTLZ_STRICT_ALIGN)
+#define FASTLZ_STRICT_ALIGN
+#if defined(__i386__) || defined(__386) /* GNU C, Sun Studio */
+#undef FASTLZ_STRICT_ALIGN
+#elif defined(__i486__) || defined(__i586__) || defined(__i686__) || defined(__amd64) /* GNU C */
+#undef FASTLZ_STRICT_ALIGN
+#elif defined(_M_IX86) /* Intel, MSVC */
+#undef FASTLZ_STRICT_ALIGN
+#elif defined(__386)
+#undef FASTLZ_STRICT_ALIGN
+#elif defined(_X86_) /* MinGW */
+#undef FASTLZ_STRICT_ALIGN
+#elif defined(__I86__) /* Digital Mars */
+#undef FASTLZ_STRICT_ALIGN
+#endif
+#endif
+
+/* prototypes */
+int fastlz_compress(const void* input, int length, void* output);
+int fastlz_compress_level(int level, const void* input, int length, void* output);
+int fastlz_decompress(const void* input, int length, void* output, int maxout);
+
+#define MAX_COPY 32
+#define MAX_LEN 264 /* 256 + 8 */
+#define MAX_DISTANCE 8192
+
+#if !defined(FASTLZ_STRICT_ALIGN)
+#define FASTLZ_READU16(p) *((const flzuint16*)(p))
+#else
+#define FASTLZ_READU16(p) ((p)[0] | (p)[1]<<8)
+#endif
+
+#define HASH_LOG 13
+#define HASH_SIZE (1<< HASH_LOG)
+#define HASH_MASK (HASH_SIZE-1)
+#define HASH_FUNCTION(v,p) { v = FASTLZ_READU16(p); v ^= FASTLZ_READU16(p+1)^(v>>(16-HASH_LOG));v &= HASH_MASK; }
+
+#undef FASTLZ_LEVEL
+#define FASTLZ_LEVEL 1
+
+#undef FASTLZ_COMPRESSOR
+#undef FASTLZ_DECOMPRESSOR
+#define FASTLZ_COMPRESSOR fastlz1_compress
+#define FASTLZ_DECOMPRESSOR fastlz1_decompress
+static FASTLZ_INLINE int FASTLZ_COMPRESSOR(const void* input, int length, void* output);
+static FASTLZ_INLINE int FASTLZ_DECOMPRESSOR(const void* input, int length, void* output, int maxout);
+#include "fastlz.c"
+
+#undef FASTLZ_LEVEL
+#define FASTLZ_LEVEL 2
+
+#undef MAX_DISTANCE
+#define MAX_DISTANCE 8191
+#define MAX_FARDISTANCE (65535+MAX_DISTANCE-1)
+
+#undef FASTLZ_COMPRESSOR
+#undef FASTLZ_DECOMPRESSOR
+#define FASTLZ_COMPRESSOR fastlz2_compress
+#define FASTLZ_DECOMPRESSOR fastlz2_decompress
+static FASTLZ_INLINE int FASTLZ_COMPRESSOR(const void* input, int length, void* output);
+static FASTLZ_INLINE int FASTLZ_DECOMPRESSOR(const void* input, int length, void* output, int maxout);
+#include "fastlz.c"
+
+int fastlz_compress(const void* input, int length, void* output)
+{
+ /* for short block, choose fastlz1 */
+ if(length < 65536)
+ return fastlz1_compress(input, length, output);
+
+ /* else... */
+ return fastlz2_compress(input, length, output);
+}
+
+int fastlz_decompress(const void* input, int length, void* output, int maxout)
+{
+ /* magic identifier for compression level */
+ int level = ((*(const flzuint8*)input) >> 5) + 1;
+
+ if(level == 1)
+ return fastlz1_decompress(input, length, output, maxout);
+ if(level == 2)
+ return fastlz2_decompress(input, length, output, maxout);
+
+ /* unknown level, trigger error */
+ return 0;
+}
+
+int fastlz_compress_level(int level, const void* input, int length, void* output)
+{
+ if(level == 1)
+ return fastlz1_compress(input, length, output);
+ if(level == 2)
+ return fastlz2_compress(input, length, output);
+
+ return 0;
+}
+
+#else /* !defined(FASTLZ_COMPRESSOR) && !defined(FASTLZ_DECOMPRESSOR) */
+
+static FASTLZ_INLINE int FASTLZ_COMPRESSOR(const void* input, int length, void* output)
+{
+ const flzuint8* ip = (const flzuint8*) input;
+ const flzuint8* ip_bound = ip + length - 2;
+ const flzuint8* ip_limit = ip + length - 12;
+ flzuint8* op = (flzuint8*) output;
+
+ const flzuint8* htab[HASH_SIZE];
+ const flzuint8** hslot;
+ flzuint32 hval;
+
+ flzuint32 copy;
+
+ /* sanity check */
+ if(FASTLZ_UNEXPECT_CONDITIONAL(length < 4))
+ {
+ if(length)
+ {
+ /* create literal copy only */
+ *op++ = length-1;
+ ip_bound++;
+ while(ip <= ip_bound)
+ *op++ = *ip++;
+ return length+1;
+ }
+ else
+ return 0;
+ }
+
+ /* initializes hash table */
+ for (hslot = htab; hslot < htab + HASH_SIZE; hslot++)
+ *hslot = ip;
+
+ /* we start with literal copy */
+ copy = 2;
+ *op++ = MAX_COPY-1;
+ *op++ = *ip++;
+ *op++ = *ip++;
+
+ /* main loop */
+ while(FASTLZ_EXPECT_CONDITIONAL(ip < ip_limit))
+ {
+ const flzuint8* ref;
+ flzuint32 distance;
+
+ /* minimum match length */
+ flzuint32 len = 3;
+
+ /* comparison starting-point */
+ const flzuint8* anchor = ip;
+
+ /* check for a run */
+#if FASTLZ_LEVEL==2
+ if(ip[0] == ip[-1] && FASTLZ_READU16(ip-1)==FASTLZ_READU16(ip+1))
+ {
+ distance = 1;
+ /* ip += 3; */ /* scan-build, never used */
+ ref = anchor - 1 + 3;
+ goto match;
+ }
+#endif
+
+ /* find potential match */
+ HASH_FUNCTION(hval,ip);
+ hslot = htab + hval;
+ ref = htab[hval];
+
+ /* calculate distance to the match */
+ distance = anchor - ref;
+
+ /* update hash table */
+ *hslot = anchor;
+
+ /* is this a match? check the first 3 bytes */
+ if(distance==0 ||
+#if FASTLZ_LEVEL==1
+ (distance >= MAX_DISTANCE) ||
+#else
+ (distance >= MAX_FARDISTANCE) ||
+#endif
+ *ref++ != *ip++ || *ref++!=*ip++ || *ref++!=*ip++)
+ goto literal;
+
+#if FASTLZ_LEVEL==2
+ /* far, needs at least 5-byte match */
+ if(distance >= MAX_DISTANCE)
+ {
+ if(*ip++ != *ref++ || *ip++!= *ref++)
+ goto literal;
+ len += 2;
+ }
+
+ match:
+#endif
+
+ /* last matched byte */
+ ip = anchor + len;
+
+ /* distance is biased */
+ distance--;
+
+ if(!distance)
+ {
+ /* zero distance means a run */
+ flzuint8 x = ip[-1];
+ while(ip < ip_bound)
+ if(*ref++ != x) break; else ip++;
+ }
+ else
+ for(;;)
+ {
+ /* safe because the outer check against ip limit */
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ if(*ref++ != *ip++) break;
+ while(ip < ip_bound)
+ if(*ref++ != *ip++) break;
+ break;
+ }
+
+ /* if we have copied something, adjust the copy count */
+ if(copy)
+ /* copy is biased, '0' means 1 byte copy */
+ *(op-copy-1) = copy-1;
+ else
+ /* back, to overwrite the copy count */
+ op--;
+
+ /* reset literal counter */
+ copy = 0;
+
+ /* length is biased, '1' means a match of 3 bytes */
+ ip -= 3;
+ len = ip - anchor;
+
+ /* encode the match */
+#if FASTLZ_LEVEL==2
+ if(distance < MAX_DISTANCE)
+ {
+ if(len < 7)
+ {
+ *op++ = (len << 5) + (distance >> 8);
+ *op++ = (distance & 255);
+ }
+ else
+ {
+ *op++ = (7 << 5) + (distance >> 8);
+ for(len-=7; len >= 255; len-= 255)
+ *op++ = 255;
+ *op++ = len;
+ *op++ = (distance & 255);
+ }
+ }
+ else
+ {
+ /* far away, but not yet in the another galaxy... */
+ if(len < 7)
+ {
+ distance -= MAX_DISTANCE;
+ *op++ = (len << 5) + 31;
+ *op++ = 255;
+ *op++ = distance >> 8;
+ *op++ = distance & 255;
+ }
+ else
+ {
+ distance -= MAX_DISTANCE;
+ *op++ = (7 << 5) + 31;
+ for(len-=7; len >= 255; len-= 255)
+ *op++ = 255;
+ *op++ = len;
+ *op++ = 255;
+ *op++ = distance >> 8;
+ *op++ = distance & 255;
+ }
+ }
+#else
+
+ if(FASTLZ_UNEXPECT_CONDITIONAL(len > MAX_LEN-2))
+ while(len > MAX_LEN-2)
+ {
+ *op++ = (7 << 5) + (distance >> 8);
+ *op++ = MAX_LEN - 2 - 7 -2;
+ *op++ = (distance & 255);
+ len -= MAX_LEN-2;
+ }
+
+ if(len < 7)
+ {
+ *op++ = (len << 5) + (distance >> 8);
+ *op++ = (distance & 255);
+ }
+ else
+ {
+ *op++ = (7 << 5) + (distance >> 8);
+ *op++ = len - 7;
+ *op++ = (distance & 255);
+ }
+#endif
+
+ /* update the hash at match boundary */
+ HASH_FUNCTION(hval,ip);
+ htab[hval] = ip++;
+ HASH_FUNCTION(hval,ip);
+ htab[hval] = ip++;
+
+ /* assuming literal copy */
+ *op++ = MAX_COPY-1;
+
+ continue;
+
+ literal:
+ *op++ = *anchor++;
+ ip = anchor;
+ copy++;
+ if(FASTLZ_UNEXPECT_CONDITIONAL(copy == MAX_COPY))
+ {
+ copy = 0;
+ *op++ = MAX_COPY-1;
+ }
+ }
+
+ /* left-over as literal copy */
+ ip_bound++;
+ while(ip <= ip_bound)
+ {
+ *op++ = *ip++;
+ copy++;
+ if(copy == MAX_COPY)
+ {
+ copy = 0;
+ *op++ = MAX_COPY-1;
+ }
+ }
+
+ /* if we have copied something, adjust the copy length */
+ if(copy)
+ *(op-copy-1) = copy-1;
+ else
+ op--;
+
+#if FASTLZ_LEVEL==2
+ /* marker for fastlz2 */
+ *(flzuint8*)output |= (1 << 5);
+#endif
+
+ return op - (flzuint8*)output;
+}
+
+static FASTLZ_INLINE int FASTLZ_DECOMPRESSOR(const void* input, int length, void* output, int maxout)
+{
+ const flzuint8* ip = (const flzuint8*) input;
+ const flzuint8* ip_limit = ip + length;
+ flzuint8* op = (flzuint8*) output;
+ flzuint8* op_limit = op + maxout;
+ flzuint32 ctrl = (*ip++) & 31;
+ int loop = 1;
+
+ do
+ {
+ const flzuint8* ref = op;
+ flzuint32 len = ctrl >> 5;
+ flzuint32 ofs = (ctrl & 31) << 8;
+
+ if(ctrl >= 32)
+ {
+#if FASTLZ_LEVEL==2
+ flzuint8 code;
+#endif
+ len--;
+ ref -= ofs;
+ if (len == 7-1)
+#if FASTLZ_LEVEL==1
+ len += *ip++;
+ ref -= *ip++;
+#else
+ do
+ {
+ code = *ip++;
+ len += code;
+ } while (code==255);
+ code = *ip++;
+ ref -= code;
+
+ /* match from 16-bit distance */
+ if(FASTLZ_UNEXPECT_CONDITIONAL(code==255))
+ if(FASTLZ_EXPECT_CONDITIONAL(ofs==(31 << 8)))
+ {
+ ofs = (*ip++) << 8;
+ ofs += *ip++;
+ ref = op - ofs - MAX_DISTANCE;
+ }
+#endif
+
+#ifdef FASTLZ_SAFE
+ if (FASTLZ_UNEXPECT_CONDITIONAL(op + len + 3 > op_limit))
+ return 0;
+
+ if (FASTLZ_UNEXPECT_CONDITIONAL(ref-1 < (flzuint8 *)output))
+ return 0;
+#endif
+
+ if(FASTLZ_EXPECT_CONDITIONAL(ip < ip_limit))
+ ctrl = *ip++;
+ else
+ loop = 0;
+
+ if(ref == op)
+ {
+ /* optimize copy for a run */
+ flzuint8 b = ref[-1];
+ *op++ = b;
+ *op++ = b;
+ *op++ = b;
+ for(; len; --len)
+ *op++ = b;
+ }
+ else
+ {
+#if !defined(FASTLZ_STRICT_ALIGN)
+ const flzuint16* p;
+ flzuint16* q;
+#endif
+ /* copy from reference */
+ ref--;
+ *op++ = *ref++;
+ *op++ = *ref++;
+ *op++ = *ref++;
+
+#if !defined(FASTLZ_STRICT_ALIGN)
+ /* copy a byte, so that now it's word aligned */
+ if(len & 1)
+ {
+ *op++ = *ref++;
+ len--;
+ }
+
+ /* copy 16-bit at once */
+ q = (flzuint16*) op;
+ op += len;
+ p = (const flzuint16*) ref;
+ for(len>>=1; len > 4; len-=4)
+ {
+ *q++ = *p++;
+ *q++ = *p++;
+ *q++ = *p++;
+ *q++ = *p++;
+ }
+ for(; len; --len)
+ *q++ = *p++;
+#else
+ for(; len; --len)
+ *op++ = *ref++;
+#endif
+ }
+ }
+ else
+ {
+ ctrl++;
+#ifdef FASTLZ_SAFE
+ if (FASTLZ_UNEXPECT_CONDITIONAL(op + ctrl > op_limit))
+ return 0;
+ if (FASTLZ_UNEXPECT_CONDITIONAL(ip + ctrl > ip_limit))
+ return 0;
+#endif
+
+ *op++ = *ip++;
+ for(--ctrl; ctrl; ctrl--)
+ *op++ = *ip++;
+
+ loop = FASTLZ_EXPECT_CONDITIONAL(ip < ip_limit);
+ if(loop)
+ ctrl = *ip++;
+ }
+ }
+ while(FASTLZ_EXPECT_CONDITIONAL(loop));
+
+ return op - (flzuint8*)output;
+}
+
+#endif /* !defined(FASTLZ_COMPRESSOR) && !defined(FASTLZ_DECOMPRESSOR) */
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