xz/src/lzmadec/lzmadec.c

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2007-12-08 22:42:33 +00:00
///////////////////////////////////////////////////////////////////////////////
//
/// \file lzmadec.c
/// \brief Simple single-threaded tool to uncompress .lzma files
//
// Copyright (C) 2007 Lasse Collin
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
///////////////////////////////////////////////////////////////////////////////
#include "sysdefs.h"
#ifdef HAVE_ERRNO_H
# include <errno.h>
#else
extern int errno;
#endif
#include <stdio.h>
#include <unistd.h>
#include "getopt.h"
#include "physmem.h"
enum return_code {
SUCCESS,
ERROR,
WARNING,
};
enum format_type {
FORMAT_AUTO,
FORMAT_NATIVE,
FORMAT_ALONE,
};
enum {
OPTION_FORMAT = INT_MIN,
};
/// Input buffer
static uint8_t in_buf[BUFSIZ];
/// Output buffer
static uint8_t out_buf[BUFSIZ];
/// Decoder
static lzma_stream strm = LZMA_STREAM_INIT;
/// Number of bytes to use memory at maximum
static size_t mem_limit;
/// Memory allocation hooks
static lzma_allocator allocator = {
.alloc = (void *(*)(void *, size_t, size_t))(&lzma_memlimit_alloc),
.free = (void (*)(void *, void *))(&lzma_memlimit_free),
.opaque = NULL,
};
/// Program name to be shown in error messages
static const char *argv0;
/// File currently being processed
static FILE *file;
/// Name of the file currently being processed
static const char *filename;
static enum return_code exit_status = SUCCESS;
static enum format_type format_type = FORMAT_AUTO;
static bool force = false;
static void lzma_attribute((noreturn))
help(void)
{
printf(
"Usage: %s [OPTION]... [FILE]...\n"
"Uncompress files in the .lzma format to the standard output.\n"
"\n"
" -c, --stdout (ignored)\n"
" -d, --decompress (ignored)\n"
" -k, --keep (ignored)\n"
" -f, --force allow reading compressed data from a terminal\n"
" -M, --memory=NUM use NUM bytes of memory at maximum; the suffixes\n"
" k, M, G, Ki, Mi, and Gi are supported.\n"
" --format=FMT accept only files in the given file format;\n"
" possible FMTs are `auto', `native', `single',\n"
" `multi', and `alone', of which `single' and `multi'\n"
" are aliases for `native'\n"
" -h, --help display this help and exit\n"
" -V, --version display version and license information and exit\n"
"\n"
"With no FILE, or when FILE is -, read standard input.\n"
"\n"
"On this configuration, the tool will use about %zu MiB of memory at maximum.\n"
"\n"
"Report bugs to <" PACKAGE_BUGREPORT "> (in English or Finnish).\n",
argv0, (mem_limit + 512 * 1024) / (1024 * 1024));
exit(0);
}
static void lzma_attribute((noreturn))
version(void)
{
printf(
"lzmadec (LZMA Utils) " PACKAGE_VERSION "\n"
"\n"
"Copyright (C) 1999-2006 Igor Pavlov\n"
"Copyright (C) 2007 Lasse Collin\n"
"\n"
"This program is free software; you can redistribute it and/or\n"
"modify it under the terms of the GNU Lesser General Public\n"
"License as published by the Free Software Foundation; either\n"
"version 2.1 of the License, or (at your option) any later version.\n"
"\n"
"This program is distributed in the hope that it will be useful,\n"
"but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
"MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU\n"
"Lesser General Public License for more details.\n"
"\n");
exit(0);
}
/// Finds out the amount of physical memory in the system, and sets
/// a default memory usage limit.
static void
set_default_mem_limit(void)
{
uint64_t mem = physmem();
if (mem != 0) {
mem /= 3;
#if UINT64_MAX > SIZE_MAX
if (mem > SIZE_MAX)
mem = SIZE_MAX;
#endif
mem_limit = mem / 3;
} else {
// Cannot autodetect, use 10 MiB as the default limit.
mem_limit = (1U << 23) + (1U << 21);
}
return;
}
/// \brief Converts a string to size_t
///
/// This is rudely copied from src/lzma/util.c and modified a little. :-(
///
static size_t
str_to_size(const char *value)
{
size_t result = 0;
if (*value < '0' || *value > '9') {
fprintf(stderr, "%s: %s: Not a number", argv0, value);
exit(ERROR);
}
do {
// Don't overflow.
if (result > (SIZE_MAX - 9) / 10)
return SIZE_MAX;
result *= 10;
result += *value - '0';
++value;
} while (*value >= '0' && *value <= '9');
if (*value != '\0') {
// Look for suffix.
static const struct {
const char *name;
size_t multiplier;
} suffixes[] = {
{ "k", 1000 },
{ "M", 1000000 },
{ "G", 1000000000 },
{ "Ki", 1024 },
{ "Mi", 1048576 },
{ "Gi", 1073741824 },
{ NULL, 0 }
};
size_t multiplier = 0;
for (size_t i = 0; suffixes[i].name != NULL; ++i) {
if (strcmp(value, suffixes[i].name) == 0) {
multiplier = suffixes[i].multiplier;
break;
}
}
if (multiplier == 0) {
fprintf(stderr, "%s: %s: Invalid suffix",
argv0, value);
exit(ERROR);
}
// Don't overflow here either.
if (result > SIZE_MAX / multiplier)
return SIZE_MAX;
result *= multiplier;
}
return result;
}
/// Parses command line options.
static void
parse_options(int argc, char **argv)
{
static const char short_opts[] = "cdkfM:hV";
static const struct option long_opts[] = {
{ "stdout", no_argument, NULL, 'c' },
{ "to-stdout", no_argument, NULL, 'c' },
{ "decompress", no_argument, NULL, 'd' },
{ "uncompress", no_argument, NULL, 'd' },
{ "force", no_argument, NULL, 'f' },
{ "keep", no_argument, NULL, 'k' },
{ "memory", required_argument, NULL, 'M' },
{ "format", required_argument, NULL, OPTION_FORMAT },
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ NULL, 0, NULL, 0 }
};
int c;
while ((c = getopt_long(argc, argv, short_opts, long_opts, NULL))
!= -1) {
switch (c) {
case 'c':
case 'd':
case 'k':
break;
case 'f':
force = true;
break;
case 'M':
mem_limit = str_to_size(optarg);
break;
case 'h':
help();
case 'V':
version();
case OPTION_FORMAT: {
if (strcmp("auto", optarg) == 0) {
format_type = FORMAT_AUTO;
} else if (strcmp("native", optarg) == 0
|| strcmp("single", optarg) == 0
|| strcmp("multi", optarg) == 0) {
format_type = FORMAT_NATIVE;
} else if (strcmp("alone", optarg) == 0) {
format_type = FORMAT_ALONE;
} else {
fprintf(stderr, "%s: %s: Unknown file format "
"name\n", argv0, optarg);
exit(ERROR);
}
break;
}
default:
exit(ERROR);
}
}
return;
}
/// Initializes lzma_stream structure for decoding of a new Stream.
static void
init(void)
{
lzma_ret ret;
switch (format_type) {
case FORMAT_AUTO:
ret = lzma_auto_decoder(&strm, NULL, NULL);
break;
case FORMAT_NATIVE:
ret = lzma_stream_decoder(&strm, NULL, NULL);
break;
case FORMAT_ALONE:
ret = lzma_alone_decoder(&strm);
break;
default:
assert(0);
ret = LZMA_PROG_ERROR;
}
if (ret != LZMA_OK) {
fprintf(stderr, "%s: ", argv0);
if (ret == LZMA_MEM_ERROR)
fprintf(stderr, "%s\n", strerror(ENOMEM));
else
fprintf(stderr, "Internal program error (bug)\n");
exit(ERROR);
}
return;
}
static void
read_input(void)
{
strm.next_in = in_buf;
strm.avail_in = fread(in_buf, 1, BUFSIZ, file);
if (ferror(file)) {
// POSIX says that fread() sets errno if an error occurred.
// ferror() doesn't touch errno.
fprintf(stderr, "%s: %s: Error reading input file: %s\n",
argv0, filename, strerror(errno));
exit(ERROR);
}
return;
}
static bool
skip_padding(void)
{
// Handle concatenated Streams. There can be arbitrary number of
// nul-byte padding between the Streams, which must be ignored.
//
// NOTE: Concatenating LZMA_Alone files works only if at least
// one of lc, lp, and pb is non-zero. Using the concatenation
// on LZMA_Alone files is strongly discouraged.
while (true) {
while (strm.avail_in > 0) {
if (*strm.next_in != '\0')
return true;
++strm.next_in;
--strm.avail_in;
}
if (feof(file))
return false;
read_input();
}
}
static void
uncompress(void)
{
if (file == stdin && !force && isatty(STDIN_FILENO)) {
fprintf(stderr, "%s: Compressed data not read from "
"a terminal.\n%s: Use `-f' to force reading "
"from a terminal, or `-h' for help.\n",
argv0, argv0);
exit(ERROR);
}
init();
strm.avail_in = 0;
while (true) {
if (strm.avail_in == 0)
read_input();
strm.next_out = out_buf;
strm.avail_out = BUFSIZ;
const lzma_ret ret = lzma_code(&strm, LZMA_RUN);
// Write and check write error before checking decoder error.
// This way as much data as possible gets written to output
// even if decoder detected an error. Checking write error
// needs to be done before checking decoder error due to
// how concatenated Streams are handled a few lines later.
const size_t write_size = BUFSIZ - strm.avail_out;
if (fwrite(out_buf, 1, write_size, stdout) != write_size) {
// Wouldn't be a surprise if writing to stderr would
// fail too but at least try to show an error message.
fprintf(stderr, "%s: Cannot write to "
"standard output: %s\n", argv0,
strerror(errno));
exit(ERROR);
}
if (ret != LZMA_OK) {
if (ret == LZMA_STREAM_END) {
if (skip_padding()) {
init();
continue;
}
return;
}
fprintf(stderr, "%s: %s: ", argv0, filename);
switch (ret) {
case LZMA_DATA_ERROR:
fprintf(stderr, "File is corrupt\n");
exit(ERROR);
case LZMA_HEADER_ERROR:
fprintf(stderr, "Unsupported file "
"format or filters\n");
exit(ERROR);
case LZMA_MEM_ERROR:
fprintf(stderr, "%s\n", strerror(ENOMEM));
exit(ERROR);
case LZMA_BUF_ERROR:
fprintf(stderr, "Unexpected end of input\n");
exit(ERROR);
case LZMA_UNSUPPORTED_CHECK:
fprintf(stderr, "Unsupported type of "
"integrity check; not "
"verifying file integrity\n");
exit_status = WARNING;
break;
case LZMA_PROG_ERROR:
default:
fprintf(stderr, "Internal program "
"error (bug)\n");
exit(ERROR);
}
}
}
}
int
main(int argc, char **argv)
{
argv0 = argv[0];
set_default_mem_limit();
parse_options(argc, argv);
lzma_init_decoder();
lzma_memlimit *mem_limitter = lzma_memlimit_create(mem_limit);
if (mem_limitter == NULL) {
fprintf(stderr, "%s: %s\n", argv0, strerror(ENOMEM));
exit(ERROR);
}
allocator.opaque = mem_limitter;
strm.allocator = &allocator;
if (optind == argc) {
file = stdin;
filename = "(stdin)";
uncompress();
} else {
do {
if (strcmp(argv[optind], "-") == 0) {
file = stdin;
filename = "(stdin)";
uncompress();
} else {
filename = argv[optind];
file = fopen(filename, "rb");
if (file == NULL) {
fprintf(stderr, "%s: %s: %s\n",
argv0, filename,
strerror(errno));
exit(ERROR);
}
uncompress();
fclose(file);
}
} while (++optind < argc);
}
return exit_status;
}