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Diffstat (limited to 'main.cc')
| -rw-r--r-- | main.cc | 688 |
1 files changed, 688 insertions, 0 deletions
@@ -0,0 +1,688 @@ +/* Zutils - A file format detector for compressed files + Copyright (C) 2009 Antonio Diaz Diaz. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ +/* + Return values: 0 for a normal exit, 1 for environmental problems + (file not found, invalid flags, I/O errors, etc), 2 to indicate a + corrupt or invalid input file, 3 for an internal consistency error + (eg, bug) which caused zutils to panic. +*/ + +#define _FILE_OFFSET_BITS 64 + +#include <algorithm> +#include <cerrno> +#include <climits> +#include <csignal> +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <string> +#include <vector> +#include <fcntl.h> +#include <stdint.h> +#include <unistd.h> +#include <utime.h> +#include <sys/stat.h> +#include <sys/time.h> + +#include "arg_parser.h" + +#ifndef LLONG_MAX +#define LLONG_MAX 0x7FFFFFFFFFFFFFFFLL +#endif +#ifndef LLONG_MIN +#define LLONG_MIN (-LLONG_MAX - 1LL) +#endif +#ifndef ULLONG_MAX +#define ULLONG_MAX 0xFFFFFFFFFFFFFFFFULL +#endif + + +namespace { + +const char * invocation_name = 0; +const char * const Program_name = "Zutils"; +const char * const program_name = "zutils"; +const char * const program_year = "2009"; + +struct { const char * from; const char * to; } const known_extensions[] = { + { ".zf", "" }, + { 0, 0 } }; + +enum Mode { m_compress = 0, m_decompress, m_test }; + +std::string output_filename; +int outhandle = -1; +int verbosity = 0; +bool delete_output_on_interrupt = false; + + +class Pretty_print + { + const char * const stdin_name; + const unsigned int stdin_name_len; + unsigned int longest_name; + std::string name_; + mutable bool first_post; + +public: + Pretty_print( const std::vector< std::string > & filenames ) + : stdin_name( "(stdin)" ), stdin_name_len( std::strlen( stdin_name ) ), + longest_name( 0 ), first_post( false ) + { + for( unsigned int i = 0; i < filenames.size(); ++i ) + { + const std::string & s = filenames[i]; + const unsigned int len = ( ( s == "-" ) ? stdin_name_len : s.size() ); + if( len > longest_name ) longest_name = len; + } + if( longest_name == 0 ) longest_name = stdin_name_len; + } + + void set_name( const std::string & filename ) + { + if( filename.size() && filename != "-" ) name_ = filename; + else name_ = stdin_name; + first_post = true; + } + + void reset() const throw() { if( name_.size() ) first_post = true; } + const char * name() const throw() { return name_.c_str(); } + void operator()( const char * const msg = 0 ) const throw(); + }; + + +void Pretty_print::operator()( const char * const msg ) const throw() + { + if( verbosity >= 0 ) + { + if( first_post ) + { + first_post = false; + std::fprintf( stderr, " %s: ", name_.c_str() ); + for( unsigned int i = 0; i < longest_name - name_.size(); ++i ) + std::fprintf( stderr, " " ); + if( !msg ) std::fflush( stderr ); + } + if( msg ) std::fprintf( stderr, "%s.\n", msg ); + } + } + + +void show_help() throw() + { + std::printf( "%s - A file format detector for compressed files.\n", Program_name ); + std::printf( "\nUsage: %s [options] [files]\n", invocation_name ); + std::printf( "\nOptions:\n" ); + std::printf( " -h, --help display this help and exit\n" ); + std::printf( " -V, --version output version information and exit\n" ); +// std::printf( " -c, --stdout send output to standard output\n" ); +// std::printf( " -d, --decompress decompress\n" ); +// std::printf( " -f, --force overwrite existing output files\n" ); +// std::printf( " -k, --keep keep (don't delete) input files\n" ); +// std::printf( " -o, --output=<file> if reading stdin, place the output into <file>\n" ); + std::printf( " -q, --quiet suppress all messages\n" ); + std::printf( " -t, --test test compressed file type\n" ); + std::printf( " -v, --verbose be verbose (a 2nd -v gives more)\n" ); + std::printf( "\nReport bugs to zutils-bug@nongnu.org\n" ); + std::printf( "Zutils home page: http://www.nongnu.org/zutils/zutils.html\n" ); + } + + +void show_version() throw() + { + std::printf( "%s %s\n", Program_name, PROGVERSION ); + std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year ); + std::printf( "License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>\n" ); + std::printf( "This is free software: you are free to change and redistribute it.\n" ); + std::printf( "There is NO WARRANTY, to the extent permitted by law.\n" ); + } + + +void show_error( const char * msg, const int errcode = 0, const bool help = false ) throw() + { + if( verbosity >= 0 ) + { + if( msg && msg[0] != 0 ) + { + std::fprintf( stderr, "%s: %s", program_name, msg ); + if( errcode > 0 ) std::fprintf( stderr, ": %s", std::strerror( errcode ) ); + std::fprintf( stderr, "\n" ); + } + if( help && invocation_name && invocation_name[0] != 0 ) + std::fprintf( stderr, "Try `%s --help' for more information.\n", invocation_name ); + } + } + + +void internal_error( const char * msg ) + { + std::string s( "internal error: " ); s += msg; + show_error( s.c_str() ); + std::exit( 3 ); + } + + +const char * format_num( long long num, long long limit = 9999, + const int set_prefix = 0 ) throw() + { + const char * const si_prefix[8] = + { "k", "M", "G", "T", "P", "E", "Z", "Y" }; + const char * const binary_prefix[8] = + { "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi", "Yi" }; + static bool si = false; + static char buf[16]; + + if( set_prefix ) si = ( set_prefix > 0 ); + const int factor = ( si ) ? 1000 : 1024; + const char * const *prefix = ( si ) ? si_prefix : binary_prefix; + const char *p = ""; + limit = std::max( 999LL, std::min( 999999LL, limit ) ); + + for( int i = 0; i < 8 && ( llabs( num ) > limit || + ( llabs( num ) >= factor && num % factor == 0 ) ); ++i ) + { num /= factor; p = prefix[i]; } + snprintf( buf, sizeof buf, "%lld %s", num, p ); + return buf; + } + + +long long getnum( const char * ptr, const int bs, + const long long llimit = LLONG_MIN + 1, + const long long ulimit = LLONG_MAX ) throw() + { + errno = 0; + char *tail; + long long result = strtoll( ptr, &tail, 0 ); + if( tail == ptr ) + { + show_error( "bad or missing numerical argument", 0, true ); + std::exit( 1 ); + } + + if( !errno && tail[0] ) + { + int factor = ( tail[1] == 'i' ) ? 1024 : 1000; + int exponent = 0; + bool bad_multiplier = false; + switch( tail[0] ) + { + case ' ': break; + case 'b': if( bs > 0 ) { factor = bs; exponent = 1; } + else bad_multiplier = true; + break; + case 'Y': exponent = 8; break; + case 'Z': exponent = 7; break; + case 'E': exponent = 6; break; + case 'P': exponent = 5; break; + case 'T': exponent = 4; break; + case 'G': exponent = 3; break; + case 'M': exponent = 2; break; + case 'K': if( factor == 1024 ) exponent = 1; else bad_multiplier = true; + break; + case 'k': if( factor == 1000 ) exponent = 1; else bad_multiplier = true; + break; + default: bad_multiplier = true; + } + if( bad_multiplier ) + { + show_error( "bad multiplier in numerical argument", 0, true ); + std::exit( 1 ); + } + for( int i = 0; i < exponent; ++i ) + { + if( LLONG_MAX / factor >= llabs( result ) ) result *= factor; + else { errno = ERANGE; break; } + } + } + if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE; + if( errno ) + { + show_error( "numerical argument out of limits" ); + std::exit( 1 ); + } + return result; + } + + +int extension_index( const std::string & name ) throw() + { + for( int i = 0; known_extensions[i].from; ++i ) + { + const std::string ext( known_extensions[i].from ); + if( name.size() > ext.size() && + name.compare( name.size() - ext.size(), ext.size(), ext ) == 0 ) + return i; + } + return -1; + } + + +int open_instream( const std::string & name, struct stat * in_statsp, + const Mode program_mode, const int eindex, + const bool force, const bool to_stdout ) throw() + { + int inhandle = -1; + if( program_mode == m_compress && !force && eindex >= 0 ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: input file `%s' already has `%s' suffix.\n", + program_name, name.c_str(), + known_extensions[eindex].from ); + } + else + { + inhandle = open( name.c_str(), O_RDONLY ); + if( inhandle < 0 ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: Can't open input file `%s': %s.\n", + program_name, name.c_str(), std::strerror( errno ) ); + } + else + { + const int i = fstat( inhandle, in_statsp ); + const mode_t & mode = in_statsp->st_mode; + if( i < 0 || !( S_ISREG( mode ) || ( to_stdout && + ( S_ISFIFO( mode ) || S_ISSOCK( mode ) || + S_ISBLK( mode ) || S_ISCHR( mode ) ) ) ) ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: input file `%s' is not a regular file%s.\n", + program_name, name.c_str(), + to_stdout ? "" : " and `--stdout' was not specified" ); + close( inhandle ); + inhandle = -1; + } + } + } + return inhandle; + } + + +void set_c_outname( const std::string & name ) throw() + { + output_filename = name; + output_filename += known_extensions[0].from; + } + + +void set_d_outname( const std::string & name, const int i ) throw() + { + if( i >= 0 ) + { + const std::string from( known_extensions[i].from ); + if( name.size() > from.size() ) + { + output_filename.assign( name, 0, name.size() - from.size() ); + output_filename += known_extensions[i].to; + return; + } + } + output_filename = name; output_filename += ".out"; + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: can't guess original name for `%s' -- using `%s'.\n", + program_name, name.c_str(), output_filename.c_str() ); + } + + +bool open_outstream( const bool /*force*/ ) throw() + { +/* if( force ) + outhandle = open( output_filename.c_str(), O_CREAT | O_TRUNC | O_WRONLY, + S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH ); + else outhandle = open( output_filename.c_str(), O_CREAT | O_EXCL | O_WRONLY, + S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH ); + if( outhandle < 0 ) + { + if( errno == EEXIST ) outhandle = -2; else outhandle = -1; + if( verbosity >= 0 ) + { + if( outhandle == -2 ) + std::fprintf( stderr, "%s: Output file %s already exists, skipping.\n", + program_name, output_filename.c_str() ); + else + std::fprintf( stderr, "%s: Can't create output file `%s': %s.\n", + program_name, output_filename.c_str(), std::strerror( errno ) ); + } + }*/ + return ( outhandle >= 0 ); + } + + +bool check_tty( const int inhandle, const Mode program_mode ) throw() + { + if( program_mode == m_compress && isatty( outhandle ) ) + { + show_error( "I won't write compressed data to a terminal.", 0, true ); + return false; + } + if( ( program_mode == m_decompress || program_mode == m_test ) && + isatty( inhandle ) ) + { + show_error( "I won't read compressed data from a terminal.", 0, true ); + return false; + } + return true; + } + + +void cleanup_and_fail( const int retval ) throw() + { + if( delete_output_on_interrupt ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: Deleting output file `%s', if it exists.\n", + program_name, output_filename.c_str() ); + if( outhandle >= 0 ) { close( outhandle ); outhandle = -1; } + if( std::remove( output_filename.c_str() ) != 0 ) + show_error( "WARNING: deletion of output file (apparently) failed." ); + } + std::exit( retval ); + } + + + // Set permissions, owner and times. +void close_and_set_permissions( const struct stat * in_statsp, int * retvalp ) + { + int tmp = 0; + if( in_statsp ) + { + if( fchmod( outhandle, in_statsp->st_mode ) != 0 ) tmp = 1; + if( !tmp ) (void)fchown( outhandle, in_statsp->st_uid, in_statsp->st_gid ); + // fchown will in many cases return with EPERM, which can be safely ignored. + } + if( close( outhandle ) == 0 ) outhandle = -1; + else cleanup_and_fail( 1 ); + delete_output_on_interrupt = false; + if( !in_statsp ) return; + if( !tmp ) + { + struct utimbuf t; + t.actime = in_statsp->st_atime; + t.modtime = in_statsp->st_mtime; + tmp = utime( output_filename.c_str(), &t ); + } + if( tmp ) + { + if( tmp > *retvalp ) *retvalp = tmp; + show_error( "I can't change output file attributes." ); + cleanup_and_fail( *retvalp ); + } + } + + +// Returns the number of bytes really read. +// If (returned value < size) and (errno == 0), means EOF was reached. +// +int readblock( const int fd, char * buf, const int size ) throw() + { + int rest = size; + errno = 0; + while( rest > 0 ) + { + errno = 0; + const int n = read( fd, buf + size - rest, rest ); + if( n > 0 ) rest -= n; + else if( n == 0 ) break; + else if( errno != EINTR && errno != EAGAIN ) break; + } + return ( rest > 0 ) ? size - rest : size; + } + + +// Returns the number of bytes really written. +// If (returned value < size), it is always an error. +// +int writeblock( const int fd, const char * buf, const int size ) throw() + { + int rest = size; + errno = 0; + while( rest > 0 ) + { + errno = 0; + const int n = write( fd, buf + size - rest, rest ); + if( n > 0 ) rest -= n; + else if( errno && errno != EINTR && errno != EAGAIN ) break; + } + return ( rest > 0 ) ? size - rest : size; + } + +/* +int compress( const int inhandle, const Pretty_print & pp, + const struct stat * in_statsp, int * retvalp ) + { + long long in_size = 0, out_size = 0; + if( verbosity >= 1 ) + { + pp(); + if( in_size <= 0 || out_size <= 0 ) + std::fprintf( stderr, "no data compressed.\n" ); + else + std::fprintf( stderr, "%6.3f:1, %6.3f bits/byte, " + "%5.2f%% saved, %lld in, %lld out.\n", + (double)in_size / out_size, + ( 8.0 * out_size ) / in_size, + 100.0 * ( 1.0 - ( (double)out_size / in_size ) ), + in_size, out_size ); + } + return 0; + } + + +int decompress( const int inhandle, const Pretty_print & pp ) + { + if( verbosity >= 1 ) + std::fprintf( stderr, "done\n" ); + return 0; + } +*/ + +int test_type( const int inhandle, const Pretty_print & pp ) + { + unsigned char buf[5]; + const char * msg = 0; + const int size = readblock( inhandle, (char *)buf, sizeof buf ); + if( size == (int)sizeof buf ) + { + if( buf[0] == 0x1F && buf[1] == 0x8B ) + msg = "gzip"; + else if( buf[0] == 'B' && buf[1] == 'Z' && buf[2] == 'h' ) + msg = "bzip2"; + else if( buf[0] == 'L' && buf[1] == 'Z' && buf[2] == 'I' && buf[3] == 'P' ) + msg = "lzip"; + else if( buf[1] == '7' && buf[2] == 'z' && buf[3] == 'X' && buf[4] == 'Z' ) + msg = "xz"; + } + const int retval = ( msg ? 0 : 1 ); + if( verbosity >= 0 ) + { + if( verbosity >= 1 ) pp(); + if( !msg ) msg = "unknown"; + std::printf( "%s\n", msg ); + } + return retval; + } + + +extern "C" void signal_handler( int ) throw() + { + show_error( "Control-C or similar caught, quitting." ); + cleanup_and_fail( 0 ); + } + + +void set_signals() throw() + { + signal( SIGHUP, signal_handler ); + signal( SIGINT, signal_handler ); + signal( SIGTERM, signal_handler ); + } + +} // end namespace + + +int main( const int argc, const char * argv[] ) + { + int inhandle = -1; + Mode program_mode = m_compress; + bool force = false; + bool keep_input_files = false; + bool to_stdout = false; + std::string input_filename; + std::string default_output_filename; + std::vector< std::string > filenames; + invocation_name = argv[0]; + + const Arg_parser::Option options[] = + { + { 'c', "stdout", Arg_parser::no }, + { 'd', "decompress", Arg_parser::no }, + { 'f', "force", Arg_parser::no }, + { 'h', "help", Arg_parser::no }, + { 'k', "keep", Arg_parser::no }, + { 'o', "output", Arg_parser::yes }, + { 'q', "quiet", Arg_parser::no }, + { 't', "test", Arg_parser::no }, + { 'v', "verbose", Arg_parser::no }, + { 'V', "version", Arg_parser::no }, + { 0 , 0, Arg_parser::no } }; + + Arg_parser parser( argc, argv, options ); + if( parser.error().size() ) // bad option + { show_error( parser.error().c_str(), 0, true ); return 1; } + + int argind = 0; + for( ; argind < parser.arguments(); ++argind ) + { + const int code = parser.code( argind ); + if( !code ) break; // no more options + const char * arg = parser.argument( argind ).c_str(); + switch( code ) + { + case 'c': to_stdout = true; break; + case 'd': program_mode = m_decompress; break; + case 'f': force = true; break; + case 'h': show_help(); return 0; + case 'k': keep_input_files = true; break; + case 'o': default_output_filename = arg; break; + case 'q': verbosity = -1; break; + case 't': program_mode = m_test; break; + case 'v': if( verbosity < 4 ) ++verbosity; break; + case 'V': show_version(); return 0; + default : internal_error( "uncaught option" ); + } + } + + bool filenames_given = false; + for( ; argind < parser.arguments(); ++argind ) + { + if( parser.argument( argind ) != "-" ) filenames_given = true; + filenames.push_back( parser.argument( argind ) ); + } + + if( filenames.empty() ) filenames.push_back("-"); + if( filenames_given ) set_signals(); + + Pretty_print pp( filenames ); + if( program_mode == m_test ) + outhandle = -1; + + int retval = 0; + for( unsigned int i = 0; i < filenames.size(); ++i ) + { + struct stat in_stats; + output_filename.clear(); + + if( !filenames[i].size() || filenames[i] == "-" ) + { + input_filename.clear(); + inhandle = STDIN_FILENO; + if( program_mode != m_test ) + { + if( to_stdout || !default_output_filename.size() ) + outhandle = STDOUT_FILENO; + else + { + if( program_mode == m_compress ) + set_c_outname( default_output_filename ); + else output_filename = default_output_filename; + if( !open_outstream( force ) ) + { + if( outhandle == -1 && retval < 1 ) retval = 1; + close( inhandle ); inhandle = -1; + continue; + } + } + } + } + else + { + input_filename = filenames[i]; + const int eindex = extension_index( input_filename ); + inhandle = open_instream( input_filename, &in_stats, program_mode, + eindex, force, to_stdout ); + if( inhandle < 0 ) { if( retval < 1 ) retval = 1; continue; } + if( program_mode != m_test ) + { + if( to_stdout ) outhandle = STDOUT_FILENO; + else + { + if( program_mode == m_compress ) + set_c_outname( input_filename ); + else set_d_outname( input_filename, eindex ); + if( !open_outstream( force ) ) + { + if( outhandle == -1 && retval < 1 ) retval = 1; + close( inhandle ); inhandle = -1; + continue; + } + } + } + } + + if( !check_tty( inhandle, program_mode ) ) return 1; + + if( output_filename.size() && !to_stdout && program_mode != m_test ) + delete_output_on_interrupt = true; +// const struct stat * in_statsp = input_filename.size() ? &in_stats : 0; + pp.set_name( input_filename ); + int tmp = 0; + switch( program_mode ) + { + case m_compress: + /*tmp = compress( inhandle, pp, in_statsp, &retval );*/ break; + case m_decompress: + /*tmp = decompress( inhandle, pp );*/ break; + case m_test: + tmp = test_type( inhandle, pp ); break; + } + if( tmp > retval ) retval = tmp; + if( tmp && program_mode != m_test ) cleanup_and_fail( retval ); +/* + if( delete_output_on_interrupt ) + close_and_set_permissions( in_statsp, &retval ); + if( input_filename.size() ) + { + close( inhandle ); inhandle = -1; + if( !keep_input_files && !to_stdout && program_mode != m_test ) + std::remove( input_filename.c_str() ); + }*/ + } + if( outhandle >= 0 ) close( outhandle ); + return retval; + } |