diff options
Diffstat (limited to 'zcmp.cc')
| -rw-r--r-- | zcmp.cc | 74 |
1 files changed, 39 insertions, 35 deletions
@@ -1,18 +1,18 @@ -/* Zcmp - decompress and compare two files byte by byte - Copyright (C) 2010-2019 Antonio Diaz Diaz. +/* Zcmp - decompress and compare two files byte by byte + Copyright (C) 2010-2020 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 2 of the License, or - (at your option) any later version. + 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 2 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. + 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/>. + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ #define _FILE_OFFSET_BITS 64 @@ -50,22 +50,21 @@ namespace { void show_help() { - std::printf( "Zcmp compares two files ('-' means standard input), and if they differ,\n" - "tells the first byte and line number where they differ. Bytes and lines\n" - "are numbered starting with 1. If any given file is compressed, its\n" - "decompressed content is used. Compressed files are decompressed on the\n" - "fly; no temporary files are created.\n" - "\nThe formats supported are bzip2, gzip, lzip and xz.\n" + std::printf( "zcmp compares two files and, if they differ, writes to standard output the\n" + "first byte and line number where they differ. Bytes and lines are numbered\n" + "starting with 1. A hyphen '-' used as a file argument means standard input.\n" + "If any file given is compressed, its decompressed content is used. Compressed\n" + "files are decompressed on the fly; no temporary files are created.\n" + "\nThe formats supported are bzip2, gzip, lzip, and xz.\n" "\nUsage: zcmp [options] file1 [file2]\n" - "\nZcmp compares file1 to file2. If file2 is omitted zcmp tries the\n" + "\nzcmp compares file1 to file2. The standard input is used only if file1 or\n" + "file2 refers to standard input. If file2 is omitted zcmp tries the\n" "following:\n" - "\n 1. If file1 is compressed, compares its decompressed contents with\n" + "\n - If file1 is compressed, compares its decompressed contents with\n" " the corresponding uncompressed file (the name of file1 with the\n" " extension removed).\n" - "\n 2. If file1 is uncompressed, compares it with the decompressed\n" + "\n - If file1 is uncompressed, compares it with the decompressed\n" " contents of file1.[lz|bz2|gz|xz] (the first one that is found).\n" - "\n 3. If no suitable file is found, compares file1 with data read from\n" - " standard input.\n" "\nExit status is 0 if inputs are identical, 1 if different, 2 if trouble.\n" "\nOptions:\n" " -h, --help display this help and exit\n" @@ -76,7 +75,7 @@ void show_help() " -M, --format=<list> process only the formats in <list>\n" " -n, --bytes=<n> compare at most <n> bytes\n" " -N, --no-rcfile don't read runtime configuration file\n" - " -O, --force-format=[<f1>][,<f2>] force given formats (bz2, gz, lz, xz)\n" + " -O, --force-format=[<f1>][,<f2>] force the formats given (bz2, gz, lz, xz)\n" " -q, --quiet suppress all messages\n" " -s, --silent (same as --quiet)\n" " -v, --verbose verbose mode (same as --list)\n" @@ -84,7 +83,7 @@ void show_help() " --gz=<command> set compressor and options for gzip format\n" " --lz=<command> set compressor and options for lzip format\n" " --xz=<command> set compressor and options for xz format\n" - "Numbers may be followed by a multiplier: k = kB = 10^3 = 1000,\n" + "\nNumbers may be followed by a multiplier: k = kB = 10^3 = 1000,\n" "Ki = KiB = 2^10 = 1024, M = 10^6, Mi = 2^20, G = 10^9, Gi = 2^30, etc...\n" ); show_help_addr(); } @@ -326,8 +325,8 @@ int main( const int argc, const char * const argv[] ) long long max_size = -1; // < 0 means unlimited size int format_types[2] = { -1, -1 }; bool print_bytes = false; - invocation_name = argv[0]; program_name = "zcmp"; + invocation_name = ( argc > 0 ) ? argv[0] : program_name; const Arg_parser::Option options[] = { @@ -403,28 +402,33 @@ int main( const int argc, const char * const argv[] ) STDIN_FILENO : open_instream( filenames[0] ); if( infd[0] < 0 ) return 2; - if( ( files == 1 && filenames[0] == "-" ) || - ( files == 2 && check_identical( filenames[0].c_str(), - filenames[1].c_str() ) ) ) - { - if( ignore_initial[0] == ignore_initial[1] ) return 0; - else { show_error( "Can't compare parts of same file." ); return 2; } - } - if( files == 2 ) { + if( check_identical( filenames[0].c_str(), filenames[1].c_str() ) ) + { + if( ignore_initial[0] == ignore_initial[1] ) return 0; + else { show_error( "Can't compare parts of same file." ); return 2; } + } infd[1] = ( filenames[1] == "-" ) ? STDIN_FILENO : open_instream( filenames[1] ); if( infd[1] < 0 ) return 2; } else { + if( filenames[0] == "-" ) + { show_error( "Missing operand after '-'.", 0, true ); return 2; } if( format_types[0] >= 0 || format_types[1] >= 0 ) { show_error( "Two files must be given when format is specified.", 0, true ); return 2; } filenames[1] = filenames[0]; infd[1] = open_other_instream( filenames[1] ); - if( infd[1] < 0 ) { infd[1] = STDIN_FILENO; filenames[1] = "-"; } + if( infd[1] < 0 ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: Can't find file to compare with '%s'.\n", + program_name, filenames[0].c_str() ); + show_error( 0, 0, true ); return 2; + } } int old_infd[2]; // copy of file descriptors of the two files |