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yalz.cc
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yalz.cc
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#include <iostream>
#include "lz77.h"
#include <stdio.h>
int main(int argc, char** argv) {
bool compress = false;
bool decompress = false;
bool fastmode = false;
bool smallmode = false;
for (int i = 1; i < argc; ++i) {
std::string arg(argv[i]);
if (arg == "-c")
compress = true;
else if (arg == "-d")
decompress = true;
else if (arg == "-1")
fastmode = true;
else if (arg == "-2")
smallmode = true;
}
const size_t BUFSIZE = (smallmode || decompress ? 100*1024 : 10*1024*1024);
if (compress) {
std::string buff;
size_t searchlen = (fastmode ? 1 : lz77::DEFAULT_SEARCHLEN);
size_t blocksize = (smallmode ? 4096 : lz77::DEFAULT_BLOCKSIZE);
lz77::compress_t compress(searchlen, blocksize);
while (1) {
buff.resize(BUFSIZE);
size_t i = ::fread((void*)buff.data(), 1, buff.size(), stdin);
buff.resize(i);
if (i > 0) {
std::string out = compress.feed(buff);
::fwrite(out.data(), 1, out.size(), stdout);
}
if (i != BUFSIZE)
break;
}
} else if (decompress) {
std::string buff;
buff.resize(BUFSIZE);
size_t buff_size = 0;
lz77::decompress_t decompress;
std::string extra;
while (1) {
buff_size = ::fread((void*)buff.data(), 1, buff.size(), stdin);
if (buff_size == 0)
break;
std::string* what = &buff;
size_t what_size = buff_size;
while (what_size > 0) {
const unsigned char* whatd = (const unsigned char*)what->data();
bool done = decompress.feed(whatd, whatd + what_size, extra);
if (!done)
break;
const std::string& result = decompress.result();
::fwrite(result.data(), 1, result.size(), stdout);
what = &extra;
what_size = extra.size();
}
if (buff_size != BUFSIZE)
break;
}
} else {
fprintf(stderr, "Usage: %s [-1|-2] {-c|-d}, where -c is compression and -d is decompression.\n"
" Input is stdin and and output is stdout.\n"
" Add '-1' when compressing to enable fast and bad compression.\n"
" Add '-2' when compressing to enable a compression mode for small files.\n", argv[0]);
return 1;
}
return 0;
}