// Fast data compression library // Copyright (C) 2006-2011 Lasse Mikkel Reinhold // lar@quicklz.com // // QuickLZ can be used for free under the GPL 1, 2 or 3 license (where anything // released into public must be open source) or under a commercial license if such // has been acquired (see http://www.quicklz.com/order.html). The commercial license // does not cover derived or ported versions created by third parties under GPL. // 1.5.1 BETA 7 #include "quicklz.h" #if defined _MSC_VER #include #endif #if QLZ_VERSION_MAJOR != 1 || QLZ_VERSION_MINOR != 5 || QLZ_VERSION_REVISION != 1 #error quicklz.c and quicklz.h have different versions #endif #if (defined(__X86__) || defined(__i386__) || defined(i386) || defined(_M_IX86) || defined(__386__) || defined(__x86_64__) || defined(_M_X64)) #define X86X64 #endif #define MINOFFSET 2 #define UNCONDITIONAL_MATCHLEN_COMPRESSOR 12 #define UNCONDITIONAL_MATCHLEN_DECOMPRESSOR 6 #define UNCOMPRESSED_END 4 #define CWORD_LEN 4 #if QLZ_COMPRESSION_LEVEL == 1 && defined QLZ_PTR_64 && QLZ_STREAMING_BUFFER == 0 #define OFFSET_BASE source #define CAST (ui32)(size_t) #else #define OFFSET_BASE 0 #define CAST #endif #if defined(X86X64) && (defined(__GNUC__) || defined(__INTEL_COMPILER)) #define qlz_likely(x) __builtin_expect (x, 1) #define qlz_unlikely(x) __builtin_expect (x, 0) #else #define qlz_likely(x) (x) #define qlz_unlikely(x) (x) #endif int qlz_get_setting(int setting) { switch (setting) { case 0: return QLZ_COMPRESSION_LEVEL; case 1: return sizeof(qlz_state_compress); case 2: return sizeof(qlz_state_decompress); case 3: return QLZ_STREAMING_BUFFER; #ifdef QLZ_MEMORY_SAFE case 6: return 1; #else case 6: return 0; #endif case 7: return QLZ_VERSION_MAJOR; case 8: return QLZ_VERSION_MINOR; case 9: return QLZ_VERSION_REVISION; } return -1; } #if QLZ_COMPRESSION_LEVEL == 1 static int same(const unsigned char *src, size_t n) { while (n > 0 && *(src + n) == *src) n--; return n == 0 ? 1 : 0; } #endif static void reset_table_compress(qlz_state_compress *state) { int i; for (i = 0; i < QLZ_HASH_VALUES; i++) { #if QLZ_COMPRESSION_LEVEL == 1 state->hash[i].offset = 0; #else state->hash_counter[i] = 0; #endif } } static void reset_table_decompress(qlz_state_decompress *state) { int i; (void)state; (void)i; #if QLZ_COMPRESSION_LEVEL == 2 for (i = 0; i < QLZ_HASH_VALUES; i++) { state->hash_counter[i] = 0; } #endif } static __inline ui32 hash_func(ui32 i) { #if QLZ_COMPRESSION_LEVEL == 2 return ((i >> 9) ^(i >> 13) ^ i) & (QLZ_HASH_VALUES - 1); #else return ((i >> 12) ^ i) & (QLZ_HASH_VALUES - 1); #endif } static __inline ui32 fast_read(void const *src, ui32 bytes) { #ifndef X86X64 unsigned char *p = (unsigned char *)src; switch (bytes) { case 4: return(*p | *(p + 1) << 8 | *(p + 2) << 16 | *(p + 3) << 24); case 3: return(*p | *(p + 1) << 8 | *(p + 2) << 16); case 2: return(*p | *(p + 1) << 8); case 1: return(*p); } return 0; #else if (bytes >= 1 && bytes <= 4) return *((ui32 *)src); else return 0; #endif } static __inline ui32 hashat(const unsigned char *src) { ui32 fetch, hash; fetch = fast_read(src, 3); hash = hash_func(fetch); return hash; } static __inline void fast_write(ui32 f, void *dst, size_t bytes) { #ifndef X86X64 unsigned char *p = (unsigned char *)dst; switch (bytes) { case 4: *p = (unsigned char)f; *(p + 1) = (unsigned char)(f >> 8); *(p + 2) = (unsigned char)(f >> 16); *(p + 3) = (unsigned char)(f >> 24); return; case 3: *p = (unsigned char)f; *(p + 1) = (unsigned char)(f >> 8); *(p + 2) = (unsigned char)(f >> 16); return; case 2: *p = (unsigned char)f; *(p + 1) = (unsigned char)(f >> 8); return; case 1: *p = (unsigned char)f; return; } #else switch (bytes) { case 4: *((ui32 *)dst) = f; return; case 3: *((ui32 *)dst) = f; return; case 2: *((ui16 *)dst) = (ui16)f; return; case 1: *((unsigned char *)dst) = (unsigned char)f; return; } #endif } size_t qlz_size_decompressed(const char *source) { ui32 n, r; n = (((*source) & 2) == 2) ? 4 : 1; r = fast_read(source + 1 + n, n); r = r & (0xffffffff >> ((4 - n)*8)); return r; } size_t qlz_size_compressed(const char *source) { ui32 n, r; n = (((*source) & 2) == 2) ? 4 : 1; r = fast_read(source + 1, n); r = r & (0xffffffff >> ((4 - n)*8)); return r; } size_t qlz_size_header(const char *source) { size_t n = 2*((((*source) & 2) == 2) ? 4 : 1) + 1; return n; } static __inline void memcpy_up(unsigned char *dst, const unsigned char *src, ui32 n) { // Caution if modifying memcpy_up! Overlap of dst and src must be special handled. #ifndef X86X64 unsigned char *end = dst + n; while (dst < end) { *dst = *src; dst++; src++; } #else ui32 f = 0; do { *(ui32 *)(dst + f) = *(ui32 *)(src + f); f += MINOFFSET + 1; } while (f < n); #endif } static __inline void update_hash(qlz_state_decompress *state, const unsigned char *s) { #if QLZ_COMPRESSION_LEVEL == 1 ui32 hash; hash = hashat(s); state->hash[hash].offset = s; state->hash_counter[hash] = 1; #elif QLZ_COMPRESSION_LEVEL == 2 ui32 hash; unsigned char c; hash = hashat(s); c = state->hash_counter[hash]; state->hash[hash].offset[c & (QLZ_POINTERS - 1)] = s; c++; state->hash_counter[hash] = c; #endif (void)state; (void)s; } #if QLZ_COMPRESSION_LEVEL <= 2 static void update_hash_upto(qlz_state_decompress *state, unsigned char **lh, const unsigned char *max) { while (*lh < max) { (*lh)++; update_hash(state, *lh); } } #endif static size_t qlz_compress_core(const unsigned char *source, unsigned char *destination, size_t size, qlz_state_compress *state) { const unsigned char *last_byte = source + size - 1; const unsigned char *src = source; unsigned char *cword_ptr = destination; unsigned char *dst = destination + CWORD_LEN; ui32 cword_val = 1U << 31; const unsigned char *last_matchstart = last_byte - UNCONDITIONAL_MATCHLEN_COMPRESSOR - UNCOMPRESSED_END; ui32 fetch = 0; unsigned int lits = 0; (void) lits; if (src <= last_matchstart) fetch = fast_read(src, 3); while (qlz_likely(src <= last_matchstart)) { if (qlz_unlikely((cword_val & 1) == 1)) { // store uncompressed if compression ratio is too low if (src > source + (size >> 1) && dst - destination > src - source - ((src - source) >> 5)) return 0; fast_write((cword_val >> 1) | (1U << 31), cword_ptr, CWORD_LEN); cword_ptr = dst; dst += CWORD_LEN; cword_val = 1U << 31; fetch = fast_read(src, 3); } #if QLZ_COMPRESSION_LEVEL == 1 { const unsigned char *o; ui32 hash, cached; hash = hash_func(fetch); cached = fetch ^ state->hash[hash].cache; state->hash[hash].cache = fetch; o = state->hash[hash].offset + OFFSET_BASE; state->hash[hash].offset = CAST(src - OFFSET_BASE); #ifdef X86X64 if ((cached & 0xffffff) == 0 && o != OFFSET_BASE && (src - o > MINOFFSET || (src == o + 1 && lits >= 3 && src > source + 3 && same(src - 3, 6)))) { #else if (cached == 0 && o != OFFSET_BASE && (src - o > MINOFFSET || (src == o + 1 && lits >= 3 && src > source + 3 && same(src - 3, 6)))) { #endif size_t matchlen = 3; hash <<= 4; cword_val = (cword_val >> 1) | (1U << 31); #if defined X86X64 && defined QLZ_PTR_64 { #ifdef __GNUC__ unsigned long long a = *(unsigned long long *)(src + matchlen); unsigned long long b = *(unsigned long long *)(o + matchlen); unsigned long long c = a^b; #else unsigned int a = *(unsigned int *)(src + matchlen); unsigned int b = *(unsigned int *)(o + matchlen); unsigned int c = a^b; #endif if (qlz_unlikely(c == 0)) { size_t q = last_byte - UNCOMPRESSED_END - src + 1; size_t remaining = q > 255 ? 255 : q; matchlen += sizeof(c); while (src[matchlen] == o[matchlen] && matchlen < remaining) matchlen++; } else { #if defined _MSC_VER || defined __INTEL_COMPILER unsigned int index = 0; _BitScanForward((unsigned long *)&index, c); matchlen += index >> 3; #else matchlen += __builtin_ctzll(c) >> 3; #endif } } #else if (src[matchlen] == o[matchlen]) { size_t q = last_byte - UNCOMPRESSED_END - src + 1; size_t remaining = q > 255 ? 255 : q; matchlen ++; while (src[matchlen] == o[matchlen] && matchlen < remaining) matchlen++; } #endif src += matchlen; if (qlz_likely(matchlen < 18)) { fast_write((ui32)(matchlen - 2) | hash, dst, 2); dst += 2; } else { fast_write((ui32)(matchlen << 16) | hash, dst, 3); dst += 3; } fetch = fast_read(src, 3); lits = 0; } else { lits++; *dst = *src; src++; dst++; cword_val = (cword_val >> 1); #ifdef X86X64 fetch = fast_read(src, 3); #else fetch = (fetch >> 8 & 0xffff) | (*(src + 2) << 16); #endif } } #elif QLZ_COMPRESSION_LEVEL >= 2 { const unsigned char *o, *offset2; ui32 hash, matchlen, k, m, best_k = 0; unsigned char c; size_t remaining = (last_byte - UNCOMPRESSED_END - src + 1) > 255 ? 255 : (last_byte - UNCOMPRESSED_END - src + 1); (void)best_k; fetch = fast_read(src, 3); hash = hash_func(fetch); c = state->hash_counter[hash]; offset2 = state->hash[hash].offset[0]; if (offset2 < src - MINOFFSET && c > 0 && ((fast_read(offset2, 3) ^ fetch) & 0xffffff) == 0) { matchlen = 3; if (*(offset2 + matchlen) == *(src + matchlen)) { matchlen = 4; while (*(offset2 + matchlen) == *(src + matchlen) && matchlen < remaining) matchlen++; } } else matchlen = 0; for (k = 1; k < QLZ_POINTERS && c > k; k++) { o = state->hash[hash].offset[k]; #if QLZ_COMPRESSION_LEVEL == 3 if (((fast_read(o, 3) ^ fetch) & 0xffffff) == 0 && o < src - MINOFFSET) #elif QLZ_COMPRESSION_LEVEL == 2 if (*(src + matchlen) == *(o + matchlen) && ((fast_read(o, 3) ^ fetch) & 0xffffff) == 0 && o < src - MINOFFSET) #endif { m = 3; while (*(o + m) == *(src + m) && m < remaining) m++; #if QLZ_COMPRESSION_LEVEL == 3 if ((m > matchlen) || (m == matchlen && o > offset2)) #elif QLZ_COMPRESSION_LEVEL == 2 if (m > matchlen) #endif { offset2 = o; matchlen = m; best_k = k; } } } o = offset2; state->hash[hash].offset[c & (QLZ_POINTERS - 1)] = src; c++; state->hash_counter[hash] = c; #if QLZ_COMPRESSION_LEVEL == 3 if (matchlen > 2 && src - o < 131071) { ui32 u; size_t offset = src - o; for (u = 1; u < matchlen; u++) { hash = hashat(src + u); c = state->hash_counter[hash]++; state->hash[hash].offset[c & (QLZ_POINTERS - 1)] = src + u; } cword_val = (cword_val >> 1) | (1U << 31); src += matchlen; if (matchlen == 3 && offset <= 63) { *dst = (unsigned char)(offset << 2); dst++; } else if (matchlen == 3 && offset <= 16383) { ui32 f = (ui32)((offset << 2) | 1); fast_write(f, dst, 2); dst += 2; } else if (matchlen <= 18 && offset <= 1023) { ui32 f = ((matchlen - 3) << 2) | ((ui32)offset << 6) | 2; fast_write(f, dst, 2); dst += 2; } else if (matchlen <= 33) { ui32 f = ((matchlen - 2) << 2) | ((ui32)offset << 7) | 3; fast_write(f, dst, 3); dst += 3; } else { ui32 f = ((matchlen - 3) << 7) | ((ui32)offset << 15) | 3; fast_write(f, dst, 4); dst += 4; } } else { *dst = *src; src++; dst++; cword_val = (cword_val >> 1); } #elif QLZ_COMPRESSION_LEVEL == 2 if (matchlen > 2) { cword_val = (cword_val >> 1) | (1U << 31); src += matchlen; if (matchlen < 10) { ui32 f = best_k | ((matchlen - 2) << 2) | (hash << 5); fast_write(f, dst, 2); dst += 2; } else { ui32 f = best_k | (matchlen << 16) | (hash << 5); fast_write(f, dst, 3); dst += 3; } } else { *dst = *src; src++; dst++; cword_val = (cword_val >> 1); } #endif } #endif } while (src <= last_byte) { if ((cword_val & 1) == 1) { fast_write((cword_val >> 1) | (1U << 31), cword_ptr, CWORD_LEN); cword_ptr = dst; dst += CWORD_LEN; cword_val = 1U << 31; } #if QLZ_COMPRESSION_LEVEL < 3 if (src <= last_byte - 3) { #if QLZ_COMPRESSION_LEVEL == 1 ui32 hash, fetch; fetch = fast_read(src, 3); hash = hash_func(fetch); state->hash[hash].offset = CAST(src - OFFSET_BASE); state->hash[hash].cache = fetch; #elif QLZ_COMPRESSION_LEVEL == 2 ui32 hash; unsigned char c; hash = hashat(src); c = state->hash_counter[hash]; state->hash[hash].offset[c & (QLZ_POINTERS - 1)] = src; c++; state->hash_counter[hash] = c; #endif } #endif *dst = *src; src++; dst++; cword_val = (cword_val >> 1); } while ((cword_val & 1) != 1) cword_val = (cword_val >> 1); fast_write((cword_val >> 1) | (1U << 31), cword_ptr, CWORD_LEN); // min. size must be 9 bytes so that the qlz_size functions can take 9 bytes as argument return dst - destination < 9 ? 9 : dst - destination; } static size_t qlz_decompress_core(const unsigned char *source, unsigned char *destination, size_t size, qlz_state_decompress *state, const unsigned char *history) { const unsigned char *src = source + qlz_size_header((const char *)source); unsigned char *dst = destination; const unsigned char *last_destination_byte = destination + size - 1; ui32 cword_val = 1; const unsigned char *last_matchstart = last_destination_byte - UNCONDITIONAL_MATCHLEN_DECOMPRESSOR - UNCOMPRESSED_END; unsigned char *last_hashed = destination - 1; const unsigned char *last_source_byte = source + qlz_size_compressed((const char *)source) - 1; static const ui32 bitlut[16] = {4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0}; (void) last_source_byte; (void) last_hashed; (void) state; (void) history; for (;;) { ui32 fetch; if (cword_val == 1) { #ifdef QLZ_MEMORY_SAFE if (src + CWORD_LEN - 1 > last_source_byte) return 0; #endif cword_val = fast_read(src, CWORD_LEN); src += CWORD_LEN; } #ifdef QLZ_MEMORY_SAFE if (src + 4 - 1 > last_source_byte) return 0; #endif fetch = fast_read(src, 4); if ((cword_val & 1) == 1) { ui32 matchlen; const unsigned char *offset2; #if QLZ_COMPRESSION_LEVEL == 1 ui32 hash; cword_val = cword_val >> 1; hash = (fetch >> 4) & 0xfff; offset2 = (const unsigned char *)(size_t)state->hash[hash].offset; if ((fetch & 0xf) != 0) { matchlen = (fetch & 0xf) + 2; src += 2; } else { matchlen = *(src + 2); src += 3; } #elif QLZ_COMPRESSION_LEVEL == 2 ui32 hash; unsigned char c; cword_val = cword_val >> 1; hash = (fetch >> 5) & 0x7ff; c = (unsigned char)(fetch & 0x3); offset2 = state->hash[hash].offset[c]; if ((fetch & (28)) != 0) { matchlen = ((fetch >> 2) & 0x7) + 2; src += 2; } else { matchlen = *(src + 2); src += 3; } #elif QLZ_COMPRESSION_LEVEL == 3 ui32 offset; cword_val = cword_val >> 1; if ((fetch & 3) == 0) { offset = (fetch & 0xff) >> 2; matchlen = 3; src++; } else if ((fetch & 2) == 0) { offset = (fetch & 0xffff) >> 2; matchlen = 3; src += 2; } else if ((fetch & 1) == 0) { offset = (fetch & 0xffff) >> 6; matchlen = ((fetch >> 2) & 15) + 3; src += 2; } else if ((fetch & 127) != 3) { offset = (fetch >> 7) & 0x1ffff; matchlen = ((fetch >> 2) & 0x1f) + 2; src += 3; } else { offset = (fetch >> 15); matchlen = ((fetch >> 7) & 255) + 3; src += 4; } offset2 = dst - offset; #endif #ifdef QLZ_MEMORY_SAFE if (offset2 < history || offset2 > dst - MINOFFSET - 1) return 0; if (matchlen > (ui32)(last_destination_byte - dst - UNCOMPRESSED_END + 1)) return 0; #endif memcpy_up(dst, offset2, matchlen); dst += matchlen; #if QLZ_COMPRESSION_LEVEL <= 2 update_hash_upto(state, &last_hashed, dst - matchlen); last_hashed = dst - 1; #endif } else { if (dst < last_matchstart) { unsigned int n = bitlut[cword_val & 0xf]; #ifdef X86X64 *(ui32 *)dst = *(ui32 *)src; #else memcpy_up(dst, src, 4); #endif cword_val = cword_val >> n; dst += n; src += n; #if QLZ_COMPRESSION_LEVEL <= 2 update_hash_upto(state, &last_hashed, dst - 3); #endif } else { while (dst <= last_destination_byte) { if (cword_val == 1) { src += CWORD_LEN; cword_val = 1U << 31; } #ifdef QLZ_MEMORY_SAFE if (src >= last_source_byte + 1) return 0; #endif *dst = *src; dst++; src++; cword_val = cword_val >> 1; } #if QLZ_COMPRESSION_LEVEL <= 2 update_hash_upto(state, &last_hashed, last_destination_byte - 3); // todo, use constant #endif return size; } } } } size_t qlz_compress(const void *source, char *destination, size_t size, qlz_state_compress *state) { size_t r; ui32 compressed; size_t base; if (size == 0 || size > 0xffffffff - 400) return 0; if (size < 216) base = 3; else base = 9; #if QLZ_STREAMING_BUFFER > 0 if (state->stream_counter + size - 1 >= QLZ_STREAMING_BUFFER) #endif { reset_table_compress(state); r = base + qlz_compress_core((const unsigned char *)source, (unsigned char *)destination + base, size, state); #if QLZ_STREAMING_BUFFER > 0 reset_table_compress(state); #endif if (r == base) { memcpy(destination + base, source, size); r = size + base; compressed = 0; } else { compressed = 1; } state->stream_counter = 0; } #if QLZ_STREAMING_BUFFER > 0 else { unsigned char *src = state->stream_buffer + state->stream_counter; memcpy(src, source, size); r = base + qlz_compress_core(src, (unsigned char *)destination + base, size, state); if (r == base) { memcpy(destination + base, src, size); r = size + base; compressed = 0; reset_table_compress(state); } else { compressed = 1; } state->stream_counter += size; } #endif if (base == 3) { *destination = (unsigned char)(0 | compressed); *(destination + 1) = (unsigned char)r; *(destination + 2) = (unsigned char)size; } else { *destination = (unsigned char)(2 | compressed); fast_write((ui32)r, destination + 1, 4); fast_write((ui32)size, destination + 5, 4); } *destination |= (QLZ_COMPRESSION_LEVEL << 2); *destination |= (1 << 6); *destination |= ((QLZ_STREAMING_BUFFER == 0 ? 0 : (QLZ_STREAMING_BUFFER == 100000 ? 1 : (QLZ_STREAMING_BUFFER == 1000000 ? 2 : 3))) << 4); // 76543210 // 01SSLLHC return r; } size_t qlz_decompress(const char *source, void *destination, qlz_state_decompress *state) { size_t dsiz = qlz_size_decompressed(source); size_t csiz = qlz_size_compressed(source); #if QLZ_STREAMING_BUFFER > 0 if (state->stream_counter + qlz_size_decompressed(source) - 1 >= QLZ_STREAMING_BUFFER) #endif { if ((*source & 1) == 1) { reset_table_decompress(state); dsiz = qlz_decompress_core((const unsigned char *)source, (unsigned char *)destination, dsiz, state, (const unsigned char *)destination); } else { if (csiz != dsiz + qlz_size_header(source)) return 0; memcpy(destination, source + qlz_size_header(source), dsiz); } state->stream_counter = 0; reset_table_decompress(state); } #if QLZ_STREAMING_BUFFER > 0 else { unsigned char *dst = state->stream_buffer + state->stream_counter; if ((*source & 1) == 1) { dsiz = qlz_decompress_core((const unsigned char *)source, dst, dsiz, state, (const unsigned char *)state->stream_buffer); } else { // if(csiz != dsiz + qlz_size_header(source)) // return 0; memcpy(dst, source + qlz_size_header(source), dsiz); reset_table_decompress(state); } memcpy(destination, dst, dsiz); state->stream_counter += dsiz; } #endif return dsiz; }