diff options
Diffstat (limited to 'main.c')
| -rw-r--r-- | main.c | 140 |
1 files changed, 118 insertions, 22 deletions
@@ -54,6 +54,10 @@ #include "lzip.h" #include "decoder.h" +#ifndef O_BINARY +#define O_BINARY 0 +#endif + #if CHAR_BIT != 8 #error "Environments where CHAR_BIT != 8 are not supported." #endif @@ -64,12 +68,6 @@ const char * const program_name = "lunzip"; const char * const program_year = "2013"; const char * invocation_name = 0; -#ifdef O_BINARY -const int o_binary = O_BINARY; -#else -const int o_binary = 0; -#endif - struct { const char * from; const char * to; } const known_extensions[] = { { ".lz", "" }, { ".tlz", ".tar" }, @@ -86,7 +84,18 @@ bool delete_output_on_interrupt = false; static void show_help( void ) { - printf( "%s - Decompressor for lzip files.\n", Program_name ); + printf( "Lunzip is a decompressor for lzip files. It is written in C and its\n" + "small size makes it well suited for embedded devices or software\n" + "installers that need to decompress files but do not need compression\n" + "capabilities. Lunzip is fully compatible with lzip-1.4 or newer.\n" + "\nIf the size of the output buffer is specified with the '--buffer-size'\n" + "option, lunzip uses the decompressed file as dictionary for distances\n" + "beyond the buffer size and is able to decompress any file using as\n" + "little memory as 50 kB, irrespective of the dictionary size used to\n" + "compress the file. Of course, the smaller the output buffer size used in\n" + "relation to the dictionary size, the more accesses to disk are needed\n" + "and the slower the decompression is. This 'low memory' mode only works\n" + "when decompressing to a regular file.\n" ); printf( "\nUsage: %s [options] [files]\n", invocation_name ); printf( "\nOptions:\n" " -h, --help display this help and exit\n" @@ -98,6 +107,7 @@ static void show_help( void ) " -o, --output=<file> if reading stdin, place the output into <file>\n" " -q, --quiet suppress all messages\n" " -t, --test test compressed file integrity\n" + " -u, --buffer-size=<bytes> set output buffer size in bytes\n" " -v, --verbose be verbose (a 2nd -v gives more)\n" "If no file names are given, lunzip decompresses from standard input to\n" "standard output.\n" @@ -137,6 +147,73 @@ static void show_header( const File_header header ) } +static unsigned long getnum( const char * const ptr, + const unsigned long llimit, + const unsigned long ulimit ) + { + unsigned long result; + char * tail; + errno = 0; + result = strtoul( ptr, &tail, 0 ); + if( tail == ptr ) + { + show_error( "Bad or missing numerical argument.", 0, true ); + exit( 1 ); + } + + if( !errno && tail[0] ) + { + int factor = ( tail[1] == 'i' ) ? 1024 : 1000; + int exponent = 0, i; + bool bad_multiplier = false; + switch( tail[0] ) + { + case ' ': 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 ); + exit( 1 ); + } + for( i = 0; i < exponent; ++i ) + { + if( ulimit / factor >= result ) result *= factor; + else { errno = ERANGE; break; } + } + } + if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE; + if( errno ) + { + show_error( "Numerical argument out of limits.", 0, false ); + exit( 1 ); + } + return result; + } + + +static int get_dict_size( const char * const arg ) + { + char * tail; + int bits = strtol( arg, &tail, 0 ); + if( bits >= min_dictionary_bits && + bits <= max_dictionary_bits && *tail == 0 ) + return ( 1 << bits ); + return getnum( arg, min_dictionary_size, max_dictionary_size ); + } + + static int extension_index( const char * const name ) { int i; @@ -152,9 +229,9 @@ static int extension_index( const char * const name ) static int open_instream( const char * const name, struct stat * const in_statsp, - const bool testing, const bool to_stdout ) + const bool no_ofile ) { - int infd = open( name, O_RDONLY | o_binary ); + int infd = open( name, O_RDONLY | O_BINARY ); if( infd < 0 ) { if( verbosity >= 0 ) @@ -168,7 +245,6 @@ static int open_instream( const char * const name, struct stat * const in_statsp const bool can_read = ( i == 0 && ( S_ISBLK( mode ) || S_ISCHR( mode ) || S_ISFIFO( mode ) || S_ISSOCK( mode ) ) ); - const bool no_ofile = to_stdout || testing; if( i != 0 || ( !S_ISREG( mode ) && ( !can_read || !no_ofile ) ) ) { if( verbosity >= 0 ) @@ -224,7 +300,7 @@ static void set_d_outname( const char * const name, const int i ) static bool open_outstream( const bool force ) { - int flags = O_CREAT | O_WRONLY | o_binary; + int flags = O_APPEND | O_CREAT | O_RDWR | O_BINARY; if( force ) flags |= O_TRUNC; else flags |= O_EXCL; outfd = open( output_filename, flags, outfd_mode ); @@ -263,10 +339,14 @@ static void close_and_set_permissions( const struct stat * const in_statsp ) bool warning = false; if( in_statsp ) { + const mode_t mode = in_statsp->st_mode; /* fchown will in many cases return with EPERM, which can be safely ignored. */ - if( ( fchown( outfd, in_statsp->st_uid, in_statsp->st_gid ) != 0 && - errno != EPERM ) || - fchmod( outfd, in_statsp->st_mode ) != 0 ) warning = true; + if( fchown( outfd, in_statsp->st_uid, in_statsp->st_gid ) == 0 ) + { if( fchmod( outfd, mode ) != 0 ) warning = true; } + else + if( errno != EPERM || + fchmod( outfd, mode & ~( S_ISUID | S_ISGID | S_ISVTX ) ) != 0 ) + warning = true; } if( close( outfd ) != 0 ) cleanup_and_fail( 1 ); outfd = -1; @@ -283,8 +363,8 @@ static void close_and_set_permissions( const struct stat * const in_statsp ) } -static int decompress( const int infd, struct Pretty_print * const pp, - const bool testing ) +static int decompress( const int buffer_size, const int infd, + struct Pretty_print * const pp, const bool testing ) { unsigned long long partial_file_pos = 0; struct Range_decoder rdec; @@ -292,7 +372,7 @@ static int decompress( const int infd, struct Pretty_print * const pp, bool first_member; if( !Rd_init( &rdec, infd ) ) { - show_error( "Not enough memory. Find a machine with more memory.", 0, false ); + show_error( "Not enough memory.", 0, false ); cleanup_and_fail( 1 ); } @@ -332,9 +412,9 @@ static int decompress( const int infd, struct Pretty_print * const pp, if( verbosity >= 2 || ( verbosity == 1 && first_member ) ) { Pp_show_msg( pp, 0 ); if( verbosity >= 3 ) show_header( header ); } - if( !LZd_init( &decoder, header, &rdec, outfd ) ) + if( !LZd_init( &decoder, header, &rdec, buffer_size, outfd ) ) { - show_error( "Not enough memory. Find a machine with more memory.", 0, false ); + show_error( "Not enough memory. Try a smaller output buffer size.", 0, false ); cleanup_and_fail( 1 ); } result = LZd_decode_member( &decoder, pp ); @@ -431,6 +511,7 @@ int main( const int argc, const char * const argv[] ) const char * default_output_filename = ""; const char ** filenames = 0; int num_filenames = 0; + int buffer_size = max_dictionary_size; int infd = -1; int argind = 0; int retval = 0; @@ -453,6 +534,7 @@ int main( const int argc, const char * const argv[] ) { 'o', "output", ap_yes }, { 'q', "quiet", ap_no }, { 't', "test", ap_no }, + { 'u', "buffer-size", ap_yes }, { 'v', "verbose", ap_no }, { 'V', "version", ap_no }, { 0 , 0, ap_no } }; @@ -463,7 +545,7 @@ int main( const int argc, const char * const argv[] ) CRC32_init(); if( !ap_init( &parser, argc, argv, options, 0 ) ) - { show_error( "Memory exhausted.", 0, false ); return 1; } + { show_error( "Not enough memory.", 0, false ); return 1; } if( ap_error( &parser ) ) /* bad option */ { show_error( ap_error( &parser ), 0, true ); return 1; } @@ -483,6 +565,7 @@ int main( const int argc, const char * const argv[] ) case 'o': default_output_filename = arg; break; case 'q': verbosity = -1; break; case 't': testing = true; break; + case 'u': buffer_size = get_dict_size( arg ); break; case 'v': if( verbosity < 4 ) ++verbosity; break; case 'V': show_version(); return 0; default : internal_error( "uncaught option" ); @@ -507,6 +590,19 @@ int main( const int argc, const char * const argv[] ) if( strcmp( filenames[i], "-" ) != 0 ) filenames_given = true; } + if( buffer_size < max_dictionary_size ) + { + if( to_stdout || testing ) + { show_error( "'--buffer-size' is incompatible with '--stdout' and '--test'.", 0, false ); + return 1; } + if( !default_output_filename[0] ) + for( i = 0; i < num_filenames; ++i ) + if( !filenames[i][0] || strcmp( filenames[i], "-" ) == 0 ) + { show_error( "Output file must be specified when decompressing from stdin with a\n" + " reduced buffer size.", 0, false ); + return 1; } + } + if( !to_stdout && !testing && ( filenames_given || default_output_filename[0] ) ) set_signals(); @@ -547,7 +643,7 @@ int main( const int argc, const char * const argv[] ) else { input_filename = filenames[i]; - infd = open_instream( input_filename, &in_stats, testing, to_stdout ); + infd = open_instream( input_filename, &in_stats, to_stdout || testing ); if( infd < 0 ) { if( retval < 1 ) retval = 1; continue; } if( !testing ) { @@ -576,7 +672,7 @@ int main( const int argc, const char * const argv[] ) delete_output_on_interrupt = true; in_statsp = input_filename[0] ? &in_stats : 0; Pp_set_name( &pp, input_filename ); - tmp = decompress( infd, &pp, testing ); + tmp = decompress( buffer_size, infd, &pp, testing ); if( tmp > retval ) retval = tmp; if( tmp && !testing ) cleanup_and_fail( retval ); |