843 lines
25 KiB
C++
843 lines
25 KiB
C++
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#include "endian.hh" /* For R64 */
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extern "C" {
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#include "C/LzmaDec.h"
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#include "C/LzmaEnc.h"
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}
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#include "lzma.hh"
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#include <algorithm> // min,max,swap
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#include <vector>
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#include <string>
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#include <cstring> // std::memcpy
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#include <cstdio>
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#include <stdint.h>
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/* We don't want threads */
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#ifdef linux
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#include <sched.h>
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#define ForceSwitchThread() sched_yield()
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#else
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#define ForceSwitchThread()
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#endif
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int LZMA_verbose = 0;
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// -fb
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unsigned LZMA_NumFastBytes = 273;
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/*from lzma.txt:
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Set number of fast bytes - [5, 273], default: 273
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Usually big number gives a little bit better compression ratio
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and slower compression process.
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from anonymous:
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This one is hard to explain... To my knowledge (please correct me if I
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am wrong), this refers to the optimal parsing algorithm. The algorithm
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tries many different combinations of matches to find the best one. If a
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match is found that is over the fb value, then it will not be optimised,
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and will just be used straight.
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This speeds up corner cases such as pic.
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*/
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/* apparently, 0 and 1 are valid values. 0 = fast mode */
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unsigned LZMA_AlgorithmNo = 1;
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unsigned LZMA_MatchFinderCycles = 0; // default: 0
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// -pb
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unsigned LZMA_PosStateBits = 0; // default: 2, range: 0..4
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/*from lzma.txt:
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pb switch is intended for periodical data
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when period is equal 2^N.
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*/
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// -lp
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unsigned LZMA_LiteralPosStateBits = 0; // default: 0, range: 0..4
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/*from lzma.txt:
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lp switch is intended for periodical data when period is
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equal 2^N. For example, for 32-bit (4 bytes)
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periodical data you can use lp=2.
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Often it's better to set lc0, if you change lp switch.
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*/
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// -lc
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unsigned LZMA_LiteralContextBits = 1; // default: 3, range: 0..8
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/*from lzma.txt:
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Sometimes lc=4 gives gain for big files.
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from anonymous:
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The context for the literal coder is 2^(lc) long. The longer it is, the
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better the statistics, but also the slower it adapts. A tradeoff, which
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is why 3 or 4 is reccommended.
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*/
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/*
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Discoveries:
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INODES:
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Best LZMA for raw_inotab_inode(40->48): pb0 lp0 lc0
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Best LZMA for raw_root_inode(28->32): pb0 lp0 lc0
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Start LZMA(rootdir, 736 bytes)
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Yay result with pb0 lp0 lc0: 218
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Yay result with pb0 lp0 lc1: 217
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Best LZMA for rootdir(736->217): pb0 lp0 lc1
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Start LZMA(inotab, 379112 bytes)
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Yay result with pb0 lp0 lc0: 24504
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Best LZMA for inotab(379112->24504): pb0 lp0 lc0
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BLKTAB:
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Best LZMA for raw_blktab(10068->2940): pb2 lp2 lc0
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---with fastbytes=128---
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Start LZMA(blktab, 12536608 bytes)
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Yay result with pb0 lp0 lc0: 1386141
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Yay result with pb0 lp1 lc0: 1308137
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Yay result with pb0 lp2 lc0: 1305403
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Yay result with pb0 lp3 lc0: 1303072
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Yay result with pb1 lp1 lc0: 1238990
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Yay result with pb1 lp2 lc0: 1227973
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Yay result with pb1 lp3 lc0: 1221205
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Yay result with pb2 lp1 lc0: 1197035
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Yay result with pb2 lp2 lc0: 1188979
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Yay result with pb2 lp3 lc0: 1184531
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Yay result with pb3 lp1 lc0: 1183866
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Yay result with pb3 lp2 lc0: 1172994
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Yay result with pb3 lp3 lc0: 1169048
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Best LZMA for blktab(12536608->1169048): pb3 lp3 lc0
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It seems, lc=0 and pb=lp=N is a wise choice,
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where N is 2 for packed blktab and 3 for unpacked.
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FBLOCKS:
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For SPC sound+code data, the best results
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are between:
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pb0 lp0 lc0 (10%)
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pb0 lp0 lc1 (90%)
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For inotab, these were observed:
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pb1 lp0 lc1
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pb2 lp0 lc0
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pb1 lp1 lc0
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pb3 lp1 lc0
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pb1 lp2 lc0
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pb2 lp1 lc0
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For C source code data, the best results
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are between:
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pb1 lp0 lc3 (10%)
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pb0 lp0 lc3 (90%)
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Occasionally:
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pb0 lp1 lc0
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pb0 lp0 lc3 (mostly)
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pb0 lp0 lc2
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pb0 lp0 lc4
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Occasionally 2:
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pb0 lp0 lc8
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pb0 lp0 lc4
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BUT:
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Best LZMA for fblock(204944->192060): pb0 lp4 lc8 -- surprise! (INOTAB PROBABLY)
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*/
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static UInt32 SelectDictionarySizeFor(unsigned datasize)
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{
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#if 1
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if(datasize >= (1 << 30U)) return 1 << 30U;
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return datasize;
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#else
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#ifdef __GNUC__
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/* gnu c can optimize this switch statement into a fast binary
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* search, but it cannot do so for the list of the if statements.
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*/
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switch(datasize)
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{
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case 0 ... 512 : return 512;
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case 513 ... 1024: return 2048;
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case 1025 ... 4096: return 8192;
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case 4097 ... 16384: return 32768;
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case 16385 ... 65536: return 528288;
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case 65537 ... 528288: return 1048576*4;
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case 528289 ... 786432: return 1048576*16;
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default: return 1048576*32;
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}
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#else
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if(datasize <= 512) return 512;
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if(datasize <= 1024) return 1024;
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if(datasize <= 4096) return 4096;
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if(datasize <= 16384) return 32768;
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if(datasize <= 65536) return 528288;
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if(datasize <= 528288) return 1048576*4;
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if(datasize <= 786432) reutrn 1048576*16;
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return 32*1048576;
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#endif
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#endif
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}
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static void *SzAlloc(void*, size_t size)
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{ return new unsigned char[size]; }
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static void SzFree(void*, void *address)
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{ unsigned char*a = (unsigned char*)address; delete[] a; }
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static ISzAlloc LZMAalloc = { SzAlloc, SzFree };
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class MemReader: public ISeqInStream
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{
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public:
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const unsigned char* const indata;
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const size_t inlength;
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size_t pos;
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public:
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MemReader(const unsigned char* d, size_t l)
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: ISeqInStream(), indata(d), inlength(l), pos(0)
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{
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Read = ReadMethod;
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}
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static SRes ReadMethod(void *pp, void *buf, size_t *size)
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{
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MemReader& p = *(MemReader*)pp;
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size_t rem = p.inlength-p.pos;
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size_t read = *size;
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if(read > rem) read= rem;
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std::memcpy(buf, &p.indata[p.pos], read);
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*size = read;
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p.pos += read;
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return SZ_OK;
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}
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};
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class MemWriter: public ISeqOutStream
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{
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public:
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std::vector<unsigned char> buf;
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public:
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MemWriter(): ISeqOutStream(), buf() { Write = WriteMethod; }
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static size_t WriteMethod(void*pp, const void* from, size_t size)
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{
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MemWriter& p = *(MemWriter*)pp;
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const unsigned char* i = (const unsigned char*)from;
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p.buf.insert(p.buf.end(), i, i+size);
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return size;
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}
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};
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const std::vector<unsigned char> LZMACompress(const unsigned char* data, size_t length,
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unsigned pb,
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unsigned lp,
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unsigned lc)
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{
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return LZMACompress(data,length, pb,lp,lc,
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SelectDictionarySizeFor(length));
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}
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const std::vector<unsigned char> LZMACompress(
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const unsigned char* data, size_t length,
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unsigned pb,
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unsigned lp,
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unsigned lc,
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unsigned dictionarysize)
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{
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if(!length) return std::vector<unsigned char>();
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CLzmaEncProps props;
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LzmaEncProps_Init(&props);
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props.dictSize = dictionarysize;
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props.pb = pb;
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props.lp = lp;
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props.lc = lc;
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props.fb = LZMA_NumFastBytes;
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props.mc = LZMA_MatchFinderCycles;
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props.algo = LZMA_AlgorithmNo;
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props.numThreads = 1;
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switch(LZMA_AlgorithmNo)
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{
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case 0: // quick: HC4
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props.btMode = 0;
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props.level = 1;
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break;
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case 1: // full: BT4
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default:
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props.level = 9;
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props.btMode = 1;
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props.numHashBytes = 4;
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break;
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}
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CLzmaEncHandle p = LzmaEnc_Create(&LZMAalloc);
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struct AutoReleaseLzmaEnc
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{
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AutoReleaseLzmaEnc(CLzmaEncHandle pp) : p(pp) { }
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~AutoReleaseLzmaEnc()
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{ LzmaEnc_Destroy(p, &LZMAalloc, &LZMAalloc); }
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CLzmaEncHandle p;
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AutoReleaseLzmaEnc(const AutoReleaseLzmaEnc&);
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void operator=(const AutoReleaseLzmaEnc&);
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} AutoReleaser(p); // Create a destructor that ensures
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// that the CLzmaEncHandle is not leaked, even if an
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// exception happens
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int res = LzmaEnc_SetProps(p, &props);
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if(res != SZ_OK)
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{
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Error:
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return std::vector<unsigned char> ();
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}
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unsigned char propsEncoded[LZMA_PROPS_SIZE + 8];
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size_t propsSize = sizeof propsEncoded;
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res = LzmaEnc_WriteProperties(p, propsEncoded, &propsSize);
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if(res != SZ_OK) goto Error;
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MemReader is(data, length);
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MemWriter os;
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put_64(propsEncoded+LZMA_PROPS_SIZE, length);
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os.buf.insert(os.buf.end(), propsEncoded, propsEncoded+LZMA_PROPS_SIZE+8);
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res = LzmaEnc_Encode(p, &os, &is, 0, &LZMAalloc, &LZMAalloc);
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if(res != SZ_OK) goto Error;
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return os.buf;
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}
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const std::vector<unsigned char> LZMACompress(const unsigned char* data, size_t length)
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{
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return LZMACompress(data, length,
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LZMA_PosStateBits,
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LZMA_LiteralPosStateBits,
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LZMA_LiteralContextBits);
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}
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#undef RC_NORMALIZE
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const std::vector<unsigned char> LZMADeCompress
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(const unsigned char* data, size_t length, bool& ok)
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{
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if(length <= LZMA_PROPS_SIZE+8)
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{
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/*clearly_not_ok:*/
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ok = false;
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return std::vector<unsigned char> ();
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}
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uint_least64_t out_sizemax = get_64(&data[LZMA_PROPS_SIZE]);
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/*if(out_sizemax >= (size_t)~0ULL)
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{
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// cannot even allocate a vector this large.
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goto clearly_not_ok;
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}*/
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std::vector<unsigned char> result(out_sizemax);
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ELzmaStatus status;
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SizeT destlen = result.size();
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SizeT srclen = length-(LZMA_PROPS_SIZE+8);
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int res = LzmaDecode(
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&result[0], &destlen,
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&data[LZMA_PROPS_SIZE+8], &srclen,
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&data[0], LZMA_PROPS_SIZE,
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LZMA_FINISH_END,
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&status,
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&LZMAalloc);
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/*
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std::fprintf(stderr, "res=%d, status=%d, in_done=%d (buf=%d), out_done=%d (max=%d)\n",
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res,
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(int)status,
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(int)srclen, (int)length,
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(int)destlen, (int)out_sizemax);
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*/
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ok = res == SZ_OK && (status == LZMA_STATUS_FINISHED_WITH_MARK
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|| status == LZMA_STATUS_MAYBE_FINISHED_WITHOUT_MARK)
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&& srclen == (length-(LZMA_PROPS_SIZE+8))
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&& destlen == out_sizemax;
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return result;
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}
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const std::vector<unsigned char> LZMADeCompress
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(const unsigned char* data, size_t length)
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{
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bool ok_unused;
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return LZMADeCompress(data, length, ok_unused);
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}
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#if 0
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#include <stdio.h>
|
||
|
|
int main(void)
|
||
|
|
{
|
||
|
|
char Buf[2048*2048];
|
||
|
|
int s = fread(Buf,1,sizeof(Buf),stdin);
|
||
|
|
std::vector<unsigned char> result = LZMADeCompress(std::vector<unsigned char>(Buf,Buf+s));
|
||
|
|
fwrite(&result[0],1,result.size(),stdout);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
const std::vector<unsigned char> LZMACompressHeavy(const unsigned char* data, size_t length,
|
||
|
|
const char* why)
|
||
|
|
{
|
||
|
|
std::vector<unsigned char> bestresult;
|
||
|
|
char best[512];
|
||
|
|
bool first = true;
|
||
|
|
if(LZMA_verbose >= 1)
|
||
|
|
{
|
||
|
|
std::fprintf(stderr, "Start LZMA(%s, %u bytes)\n", why, (unsigned)length);
|
||
|
|
std::fflush(stderr);
|
||
|
|
}
|
||
|
|
|
||
|
|
unsigned minresultsize=0, maxresultsize=0;
|
||
|
|
unsigned sizemap[5][5][9] = {{{0}}};
|
||
|
|
|
||
|
|
bool use_small_dict = false;
|
||
|
|
|
||
|
|
for(int compress_mode = 0; compress_mode < (5*5*9); ++compress_mode)
|
||
|
|
{
|
||
|
|
const unsigned pb = compress_mode % 5;
|
||
|
|
const unsigned lp = (compress_mode / 5) % 5;
|
||
|
|
const unsigned lc = (compress_mode / 5 / 5) % 9;
|
||
|
|
|
||
|
|
std::vector<unsigned char>
|
||
|
|
result = use_small_dict
|
||
|
|
? LZMACompress(data,length,pb,lp,lc, 4096)
|
||
|
|
: LZMACompress(data,length,pb,lp,lc);
|
||
|
|
|
||
|
|
{
|
||
|
|
sizemap[pb][lp][lc] = result.size();
|
||
|
|
|
||
|
|
if(first || result.size() < minresultsize) minresultsize = result.size();
|
||
|
|
if(first || result.size() > maxresultsize) maxresultsize = result.size();
|
||
|
|
if(first || result.size() < bestresult.size())
|
||
|
|
{
|
||
|
|
sprintf(best, "pb%u lp%u lc%u",
|
||
|
|
pb,lp,lc);
|
||
|
|
if(LZMA_verbose >= 1)
|
||
|
|
std::fprintf(stderr, "Yay result with %s: %u\n", best, (unsigned)result.size());
|
||
|
|
bestresult.swap(result);
|
||
|
|
first = false;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
char tmp[512];
|
||
|
|
sprintf(tmp, "pb%u lp%u lc%u",
|
||
|
|
pb,lp,lc);
|
||
|
|
if(LZMA_verbose >= 2)
|
||
|
|
std::fprintf(stderr, "Blaa result with %s: %u\n", tmp, (unsigned)result.size());
|
||
|
|
}
|
||
|
|
if(LZMA_verbose >= 2)
|
||
|
|
{
|
||
|
|
std::fprintf(stderr, "%*s\n", (5 * (4+9+2)), "");
|
||
|
|
/* Visualize the size map: */
|
||
|
|
std::string lines[6] = {};
|
||
|
|
for(unsigned pbt = 0; pbt <= 4; ++pbt)
|
||
|
|
{
|
||
|
|
char buf[64]; sprintf(buf, "pb%u:%11s", pbt,"");
|
||
|
|
lines[0] += buf;
|
||
|
|
|
||
|
|
for(unsigned lpt = 0; lpt <= 4; ++lpt)
|
||
|
|
{
|
||
|
|
char buf[64]; sprintf(buf, "lp%u:", lpt);
|
||
|
|
std::string line;
|
||
|
|
line += buf;
|
||
|
|
for(unsigned lct = 0; lct <= 8; ++lct)
|
||
|
|
{
|
||
|
|
unsigned s = sizemap[pbt][lpt][lct];
|
||
|
|
char c;
|
||
|
|
if(!s) c = '.';
|
||
|
|
else c = 'a' + ('z'-'a'+1)
|
||
|
|
* (s - minresultsize)
|
||
|
|
/ (maxresultsize-minresultsize+1);
|
||
|
|
line += c;
|
||
|
|
}
|
||
|
|
lines[1 + lpt] += line + " ";
|
||
|
|
}
|
||
|
|
}
|
||
|
|
for(unsigned a=0; a<6; ++a) std::fprintf(stderr, "%s\n", lines[a].c_str());
|
||
|
|
std::fprintf(stderr, "\33[%uA", 7);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if(LZMA_verbose >= 2)
|
||
|
|
std::fprintf(stderr, "\n\n\n\n\n\n\n\n");
|
||
|
|
|
||
|
|
if(LZMA_verbose >= 1)
|
||
|
|
{
|
||
|
|
std::fprintf(stderr, "Best LZMA for %s(%u->%u): %s\n",
|
||
|
|
why,
|
||
|
|
(unsigned)length,
|
||
|
|
(unsigned)bestresult.size(),
|
||
|
|
best);
|
||
|
|
}
|
||
|
|
std::fflush(stderr);
|
||
|
|
return bestresult;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
|
||
|
|
The LZMA compression power is controlled by these parameters:
|
||
|
|
Dictionary size (we use the maximum)
|
||
|
|
Compression algorithm (we use BT4, the heaviest available)
|
||
|
|
Number of fast bytes (we use the maximum)
|
||
|
|
pb (0..4), lp (0..4) and lc (0..8) -- the effect of these depends on data.
|
||
|
|
|
||
|
|
Since the only parameters whose effect depends on the data to be compressed
|
||
|
|
are the three (pb, lp, lc), the "auto" and "full" compression algorithms
|
||
|
|
only try to find the optimal values for those.
|
||
|
|
|
||
|
|
The "auto" LZMA compression algorithm is based on these two assumptions:
|
||
|
|
- It is possible to find the best value for each component (pb, lp, lc)
|
||
|
|
by individually testing the most effective one of them while keeping
|
||
|
|
the others static.
|
||
|
|
I.e., step 1: pb=<find best>, lp=0, lc=0
|
||
|
|
step 2: pb=<use result>, lp=<find best>, lc=0
|
||
|
|
step 3: pb=<use result>, lp=<use result>, lc=<find best>
|
||
|
|
final: pb=<use result>, lp=<use result>, lc=<use result>
|
||
|
|
- That the effect of each of these components forms a parabolic function
|
||
|
|
that has a starting point, ending point, and possibly a mountain or a
|
||
|
|
valley somewhere in the middle, but never a valley _and_ a mountain, nor
|
||
|
|
two valleys nor two mountains.
|
||
|
|
These assumptions are not always true, but it gets very close to the optimum.
|
||
|
|
|
||
|
|
The ParabolicFinder class below finds the lowest point in a parabolic curve
|
||
|
|
with a small number of tests, determining the shape of the curve by sampling
|
||
|
|
a few cue values as needed.
|
||
|
|
|
||
|
|
The algorithm is like this:
|
||
|
|
Never check any value more than once.
|
||
|
|
Check the first two values.
|
||
|
|
If they differ, then check the last in sequence.
|
||
|
|
If not, then check everything in sequential order.
|
||
|
|
If the first two values and the last form an ascending sequence, accept the first value.
|
||
|
|
If they form a descending sequence, start Focus Mode
|
||
|
|
such that the focus lower limit is index 2 and upper
|
||
|
|
limit is the second last. Then check the second last.
|
||
|
|
If they don't, then check the third value of sequence,
|
||
|
|
and everything else in sequential order.
|
||
|
|
If in Focus Mode, check if being in the lower or upper end of the focus.
|
||
|
|
If in upper end, check if the current value is bigger than the next one.
|
||
|
|
If it is, end the process, because the smallest value has already been found.
|
||
|
|
If not, next check the value at focus_low, and increase focus_low.
|
||
|
|
If in lower end, check if the current value is bigger than the previous one.
|
||
|
|
If it is, end the process, because the smallest value has already been found.
|
||
|
|
If not, next check the value at focus_high, and decrease focus_high.
|
||
|
|
|
||
|
|
For any sample space, it generally does 3 tests, but if it detects a curve
|
||
|
|
forming a valley, it may do more.
|
||
|
|
|
||
|
|
Note that ParabolicFinder does not _indicate_ the lowest value. It leaves that
|
||
|
|
to the caller. It just stops searching when it thinks that no lower value will
|
||
|
|
be found.
|
||
|
|
|
||
|
|
Note: The effect of pb, lp and lc depend also on the dictionary size setting
|
||
|
|
and compression algorithm. You cannot estimate the optimal value for those
|
||
|
|
parameters reliably using different compression settings than in the actual case.
|
||
|
|
|
||
|
|
*/
|
||
|
|
class ParabolicFinder
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
enum QueryState { Unknown, Pending, Done };
|
||
|
|
enum InstructionType { HereYouGo, WaitingResults, End };
|
||
|
|
public:
|
||
|
|
ParabolicFinder(unsigned Start, unsigned End)
|
||
|
|
: begin(Start),
|
||
|
|
results(End-Start+1, 0),
|
||
|
|
state (End-Start+1, Unknown),
|
||
|
|
LeftRightSwap(false)
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
InstructionType GetNextInstruction(unsigned& attempt)
|
||
|
|
{
|
||
|
|
InstructionType result = End;
|
||
|
|
|
||
|
|
const int Last = begin + results.size()-1;
|
||
|
|
|
||
|
|
#define RetIns(n) do{ result = (n); goto DoneCrit; }while(0)
|
||
|
|
#define RetVal(n) do{ state[attempt = (n)] = Pending; RetIns(HereYouGo); }while(0)
|
||
|
|
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
std::fprintf(stderr, "NextInstruction...");
|
||
|
|
for(unsigned a=0; a<state.size(); ++a)
|
||
|
|
std::fprintf(stderr, " %u=%s", a,
|
||
|
|
state[a]==Unknown?"??"
|
||
|
|
:state[a]==Done?"Ok"
|
||
|
|
:"..");
|
||
|
|
std::fprintf(stderr, "\n");*/
|
||
|
|
|
||
|
|
if(CountUnknown() == 0)
|
||
|
|
{
|
||
|
|
// No unassigned slots remain. Don't need more workers.
|
||
|
|
RetIns(End);
|
||
|
|
}
|
||
|
|
|
||
|
|
if(1) // scope for local variables
|
||
|
|
{
|
||
|
|
// Alternate which side to do next if both are available.
|
||
|
|
bool LeftSideFirst = LeftRightSwap ^= 1;
|
||
|
|
|
||
|
|
// Check left side descend type
|
||
|
|
int LeftSideNext = -1; bool LeftSideDoable = false;
|
||
|
|
for(int c=0; c<=Last; ++c)
|
||
|
|
switch(state[c])
|
||
|
|
{
|
||
|
|
case Unknown: LeftSideNext = c; LeftSideDoable = true; goto ExitLeftSideFor;
|
||
|
|
case Pending: LeftSideNext = c; LeftSideDoable = false; goto ExitLeftSideFor;
|
||
|
|
case Done:
|
||
|
|
if(c == 0) continue;
|
||
|
|
if(results[c] > results[c-1])
|
||
|
|
{
|
||
|
|
// Left side stopped descending.
|
||
|
|
if(state[Last] != Unknown) RetIns(End);
|
||
|
|
goto ExitLeftSideFor;
|
||
|
|
}
|
||
|
|
else if(results[c] == results[c-1])
|
||
|
|
LeftSideFirst = true;
|
||
|
|
}
|
||
|
|
ExitLeftSideFor: ;
|
||
|
|
|
||
|
|
// Check right side descend type
|
||
|
|
int RightSideNext = -1; bool RightSideDoable = false;
|
||
|
|
for(int c=Last; c>=0; --c)
|
||
|
|
switch(state[c])
|
||
|
|
{
|
||
|
|
case Unknown: RightSideNext = c; RightSideDoable = true; goto ExitRightSideFor;
|
||
|
|
case Pending: RightSideNext = c; RightSideDoable = false; goto ExitRightSideFor;
|
||
|
|
case Done:
|
||
|
|
if(c == Last) continue;
|
||
|
|
if(results[c] > results[c+1])
|
||
|
|
{
|
||
|
|
// Right side stopped descending.
|
||
|
|
if(state[0] != Unknown) RetIns(End);
|
||
|
|
goto ExitRightSideFor;
|
||
|
|
}
|
||
|
|
else if(results[c] == results[c+1])
|
||
|
|
LeftSideFirst = false;
|
||
|
|
}
|
||
|
|
ExitRightSideFor: ;
|
||
|
|
|
||
|
|
if(!LeftSideFirst)
|
||
|
|
{ std::swap(LeftSideDoable, RightSideDoable);
|
||
|
|
std::swap(LeftSideNext, RightSideNext); }
|
||
|
|
|
||
|
|
if(LeftSideDoable) RetVal(LeftSideNext);
|
||
|
|
if(RightSideDoable) RetVal(RightSideNext);
|
||
|
|
|
||
|
|
// If we have excess threads and work to do, give them something
|
||
|
|
if(CountHandled() > 2) if(LeftSideNext >= 0) RetVal(LeftSideNext);
|
||
|
|
if(CountHandled() > 3) if(RightSideNext >= 0) RetVal(RightSideNext);
|
||
|
|
|
||
|
|
RetIns(WaitingResults);
|
||
|
|
}
|
||
|
|
|
||
|
|
DoneCrit: ;
|
||
|
|
}
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
void GotResult(unsigned attempt, unsigned value)
|
||
|
|
{
|
||
|
|
{
|
||
|
|
results[attempt] = value;
|
||
|
|
state[attempt] = Done;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
unsigned CountUnknown() const
|
||
|
|
{
|
||
|
|
unsigned result=0;
|
||
|
|
for(size_t a=0, b=state.size(); a<b; ++a)
|
||
|
|
if(state[a] == Unknown) ++result;
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
unsigned CountHandled() const
|
||
|
|
{
|
||
|
|
return state.size() - CountUnknown();
|
||
|
|
}
|
||
|
|
private:
|
||
|
|
unsigned begin;
|
||
|
|
std::vector<unsigned> results;
|
||
|
|
std::vector<QueryState> state;
|
||
|
|
bool LeftRightSwap;
|
||
|
|
};
|
||
|
|
|
||
|
|
static void LZMACompressAutoHelper(
|
||
|
|
const unsigned char* data, size_t length,
|
||
|
|
bool use_small_dict,
|
||
|
|
const char* why,
|
||
|
|
unsigned& pb, unsigned& lp, unsigned& lc,
|
||
|
|
unsigned& which_iterate, ParabolicFinder& finder,
|
||
|
|
bool&first, std::vector<unsigned char>& bestresult)
|
||
|
|
{
|
||
|
|
for(;;)
|
||
|
|
{
|
||
|
|
unsigned t=0;
|
||
|
|
switch(finder.GetNextInstruction(t))
|
||
|
|
{
|
||
|
|
case ParabolicFinder::End:
|
||
|
|
return;
|
||
|
|
case ParabolicFinder::HereYouGo:
|
||
|
|
break;
|
||
|
|
case ParabolicFinder::WaitingResults:
|
||
|
|
ForceSwitchThread();
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
const unsigned try_pb = &which_iterate == &pb ? t : pb;
|
||
|
|
const unsigned try_lp = &which_iterate == &lp ? t : lp;
|
||
|
|
const unsigned try_lc = &which_iterate == &lc ? t : lc;
|
||
|
|
|
||
|
|
if(LZMA_verbose >= 2)
|
||
|
|
std::fprintf(stderr, "%s:Trying pb%u lp%u lc%u\n",
|
||
|
|
why,try_pb,try_lp,try_lc);
|
||
|
|
|
||
|
|
std::vector<unsigned char> result = use_small_dict
|
||
|
|
? LZMACompress(data,length,try_pb,try_lp,try_lc, 65536)
|
||
|
|
: LZMACompress(data,length,try_pb,try_lp,try_lc);
|
||
|
|
|
||
|
|
if(LZMA_verbose >= 2)
|
||
|
|
std::fprintf(stderr, "%s: pb%u lp%u lc%u -> %u\n",
|
||
|
|
why,try_pb,try_lp,try_lc, (unsigned)result.size());
|
||
|
|
|
||
|
|
finder.GotResult(t, result.size());
|
||
|
|
|
||
|
|
{
|
||
|
|
if(first || result.size() <= bestresult.size())
|
||
|
|
{
|
||
|
|
first = false;
|
||
|
|
bestresult.swap(result);
|
||
|
|
which_iterate = t;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
const std::vector<unsigned char> LZMACompressAuto(const unsigned char* data, size_t length,
|
||
|
|
const char* why)
|
||
|
|
{
|
||
|
|
if(LZMA_verbose >= 1)
|
||
|
|
{
|
||
|
|
std::fprintf(stderr, "Start LZMA(%s, %u bytes)\n", why, (unsigned)length);
|
||
|
|
std::fflush(stderr);
|
||
|
|
}
|
||
|
|
|
||
|
|
unsigned backup_algorithm = LZMA_AlgorithmNo;
|
||
|
|
|
||
|
|
bool use_small_dict = false;//length >= 1048576;
|
||
|
|
|
||
|
|
if(use_small_dict) LZMA_AlgorithmNo = 0;
|
||
|
|
|
||
|
|
unsigned pb=0, lp=0, lc=0;
|
||
|
|
|
||
|
|
std::vector<unsigned char> bestresult;
|
||
|
|
|
||
|
|
{
|
||
|
|
ParabolicFinder pb_finder(0,4);
|
||
|
|
ParabolicFinder lp_finder(0,4);
|
||
|
|
ParabolicFinder lc_finder(0,8);
|
||
|
|
bool first=true;
|
||
|
|
{
|
||
|
|
/* Using parallelism here. However, we need barriers after
|
||
|
|
* each step, because the comparisons are made based on the
|
||
|
|
* result size, and if the pb/lp/lc values other than the
|
||
|
|
* one being focused change, it won't work. Only one parameter
|
||
|
|
* must change in the loop.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/* step 1: find best value in pb axis */
|
||
|
|
LZMACompressAutoHelper(data,length,use_small_dict,why,
|
||
|
|
pb, lp, lc,
|
||
|
|
pb, pb_finder, first, bestresult);
|
||
|
|
|
||
|
|
|
||
|
|
lp_finder.GotResult(lp, bestresult.size());
|
||
|
|
|
||
|
|
/* step 2: find best value in lp axis */
|
||
|
|
LZMACompressAutoHelper(data,length,use_small_dict,why,
|
||
|
|
pb, lp, lc,
|
||
|
|
lp, lp_finder, first, bestresult);
|
||
|
|
|
||
|
|
lc_finder.GotResult(lc, bestresult.size());
|
||
|
|
|
||
|
|
/* step 3: find best value in lc axis */
|
||
|
|
LZMACompressAutoHelper(data,length,use_small_dict,why,
|
||
|
|
pb, lp, lc,
|
||
|
|
lc, lc_finder, first, bestresult);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
if(use_small_dict || LZMA_AlgorithmNo != backup_algorithm)
|
||
|
|
{
|
||
|
|
LZMA_AlgorithmNo = backup_algorithm;
|
||
|
|
bestresult = LZMACompress(data,length, pb,lp,lc);
|
||
|
|
}
|
||
|
|
|
||
|
|
if(LZMA_verbose >= 1)
|
||
|
|
{
|
||
|
|
std::fprintf(stderr, "Best LZMA for %s(%u->%u): pb%u lp%u lc%u\n",
|
||
|
|
why,
|
||
|
|
(unsigned)length,
|
||
|
|
(unsigned)bestresult.size(),
|
||
|
|
pb,lp,lc);
|
||
|
|
}
|
||
|
|
std::fflush(stderr);
|
||
|
|
|
||
|
|
return bestresult;
|
||
|
|
}
|
||
|
|
|
||
|
|
const std::vector<unsigned char>
|
||
|
|
DoLZMACompress(int HeavyLevel,
|
||
|
|
const unsigned char* data, size_t length,
|
||
|
|
const char* why)
|
||
|
|
{
|
||
|
|
if(HeavyLevel >= 2) return LZMACompressHeavy(data,length, why);
|
||
|
|
if(HeavyLevel >= 1) return LZMACompressAuto(data,length, why);
|
||
|
|
return LZMACompress(data,length);
|
||
|
|
}
|
||
|
|
|
||
|
|
extern "C" {
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Compress a buffer with lzma
|
||
|
|
* Don't copy the result back if it is too large.
|
||
|
|
* @param in a pointer to the buffer
|
||
|
|
* @param in_len the length in bytes
|
||
|
|
* @param out a pointer to a buffer of at least size in_len
|
||
|
|
* @param out_len a pointer to the compressed length of in
|
||
|
|
*/
|
||
|
|
|
||
|
|
void do_lzma_compress(char *in, int in_len, char *out, int *out_len) {
|
||
|
|
std::vector<unsigned char> result;
|
||
|
|
result = LZMACompress(std::vector<unsigned char>(in, in + in_len));
|
||
|
|
*out_len = result.size();
|
||
|
|
if (*out_len < in_len)
|
||
|
|
std::memcpy(out, &result[0], *out_len);
|
||
|
|
}
|
||
|
|
|
||
|
|
void do_lzma_uncompress(char *dst, int dst_len, char *src, int src_len) {
|
||
|
|
std::vector<unsigned char> result;
|
||
|
|
result = LZMADeCompress(std::vector<unsigned char>(src, src + src_len));
|
||
|
|
if (result.size() <= (SizeT)dst_len)
|
||
|
|
std::memcpy(dst, &result[0], result.size());
|
||
|
|
else
|
||
|
|
{
|
||
|
|
fprintf(stderr, "Not copying %d bytes to %d-byte buffer!\n",
|
||
|
|
(unsigned int)result.size(), dst_len);
|
||
|
|
exit(1);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
}
|
||
|
|
|