MultiMC5/depends/xz-embedded/xzminidec.c

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/*
* Simple XZ decoder command line tool
*
* Author: Lasse Collin <lasse.collin@tukaani.org>
*
* This file has been put into the public domain.
* You can do whatever you want with this file.
*/
/*
* This is really limited: Not all filters from .xz format are supported,
* only CRC32 is supported as the integrity check, and decoding of
* concatenated .xz streams is not supported. Thus, you may want to look
* at xzdec from XZ Utils if a few KiB bigger tool is not a problem.
*/
#include <stdbool.h>
#include <stdio.h>
#include <string.h>
#include "xz.h"
static uint8_t in[BUFSIZ];
static uint8_t out[BUFSIZ];
int main(int argc, char **argv)
{
struct xz_buf b;
struct xz_dec *s;
enum xz_ret ret;
const char *msg;
if (argc >= 2 && strcmp(argv[1], "--help") == 0)
{
fputs("Uncompress a .xz file from stdin to stdout.\n"
"Arguments other than `--help' are ignored.\n",
stdout);
return 0;
}
xz_crc32_init();
#ifdef XZ_USE_CRC64
xz_crc64_init();
#endif
/*
* Support up to 64 MiB dictionary. The actually needed memory
* is allocated once the headers have been parsed.
*/
s = xz_dec_init(XZ_DYNALLOC, 1 << 26);
if (s == NULL)
{
msg = "Memory allocation failed\n";
goto error;
}
b.in = in;
b.in_pos = 0;
b.in_size = 0;
b.out = out;
b.out_pos = 0;
b.out_size = BUFSIZ;
while (true)
{
if (b.in_pos == b.in_size)
{
b.in_size = fread(in, 1, sizeof(in), stdin);
b.in_pos = 0;
}
ret = xz_dec_run(s, &b);
if (b.out_pos == sizeof(out))
{
if (fwrite(out, 1, b.out_pos, stdout) != b.out_pos)
{
msg = "Write error\n";
goto error;
}
b.out_pos = 0;
}
if (ret == XZ_OK)
continue;
#ifdef XZ_DEC_ANY_CHECK
if (ret == XZ_UNSUPPORTED_CHECK)
{
fputs(argv[0], stderr);
fputs(": ", stderr);
fputs("Unsupported check; not verifying "
"file integrity\n",
stderr);
continue;
}
#endif
if (fwrite(out, 1, b.out_pos, stdout) != b.out_pos || fclose(stdout))
{
msg = "Write error\n";
goto error;
}
switch (ret)
{
case XZ_STREAM_END:
xz_dec_end(s);
return 0;
case XZ_MEM_ERROR:
msg = "Memory allocation failed\n";
goto error;
case XZ_MEMLIMIT_ERROR:
msg = "Memory usage limit reached\n";
goto error;
case XZ_FORMAT_ERROR:
msg = "Not a .xz file\n";
goto error;
case XZ_OPTIONS_ERROR:
msg = "Unsupported options in the .xz headers\n";
goto error;
case XZ_DATA_ERROR:
case XZ_BUF_ERROR:
msg = "File is corrupt\n";
goto error;
default:
msg = "Bug!\n";
goto error;
}
}
error:
xz_dec_end(s);
fputs(argv[0], stderr);
fputs(": ", stderr);
fputs(msg, stderr);
return 1;
}