singe/thirdparty/arg_parser/main.cc
2023-10-23 19:38:18 -05:00

171 lines
6.8 KiB
C++

/* Arg_parser - POSIX/GNU command line argument parser. (C++ version)
Copyright (C) 2006-2022 Antonio Diaz Diaz.
This program is free software: you have unlimited permission to
copy, distribute, and modify it.
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.
*/
/*
Exit status: 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
(e.g., bug) which caused arg_parser to panic.
*/
#include <climits>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include "arg_parser.h"
namespace {
const char * const program_name = "arg_parser";
const char * const program_year = "2022";
const char * invocation_name = program_name; // default value
void show_help( const bool verbose )
{
std::printf( "Arg_parser - POSIX/GNU command line argument parser. (C++ version)\n"
"\nArg_parser is an argument parser that follows POSIX and GNU conventions for\n"
"command line arguments. There exist C++ and C versions of Arg_parser. The\n"
"C++ version is implemented as a C++ class, while the C version is\n"
"implemented as a single struct plus associated functions. Both are simpler,\n"
"easier to use, and safer than 'getopt_long'.\n"
"\nFor maximum stability, Arg_parser is self-contained. It extracts all the\n"
"information it needs from its arguments to avoid refering to them later.\n"
"This avoids index-out-of-bounds errors.\n"
"\nArg_parser does not modify its arguments, nor uses any global variables. So\n"
"you may create more than one parser in your program if you need or want to.\n"
"\nThe C++ version of Arg_parser can also parse options from configuration\n"
"files.\n"
"\nTo use Arg_parser in your own programs simply copy the files 'arg_parser.h'\n"
"and 'arg_parser.cc' in your source tree. See the file 'main.cc' for an\n"
"example of use.\n"
"\nUsage: %s [options]\n", invocation_name );
std::printf( "\nOptions:\n"
" -h, --help display this help and exit\n"
" -V, --version output version information and exit\n"
" -a, --append example of option with no argument\n"
" -b, --block=<arg> example of option with required argument\n"
" -c, --casual[=<arg>] example of option with optional argument\n"
" -o <arg> example of short only option\n"
" --orphan example of long only option\n"
" -q, --quiet quiet operation\n"
" -u, --uncaught example of intentional bug\n"
" -v, --verbose verbose operation\n" );
if( verbose )
std::printf( " -H, --hidden example of hidden option (shown with -v -h)\n" );
std::printf( "\nReport bugs to arg-parser-bug@nongnu.org\n"
"Arg_parser home page: http://www.nongnu.org/arg-parser/arg_parser.html\n" );
}
void show_version()
{
std::printf( "%s %s\n", program_name, PROGVERSION );
std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year );
std::printf( "License 2-clause BSD.\n"
"This is free software: you are free to change and redistribute it.\n"
"There is NO WARRANTY, to the extent permitted by law.\n" );
}
void show_error( const char * const msg, const int errcode = 0,
const bool help = false )
{
if( msg && msg[0] )
std::fprintf( stderr, "%s: %s%s%s\n", program_name, msg,
( errcode > 0 ) ? ": " : "",
( errcode > 0 ) ? std::strerror( errcode ) : "" );
if( help )
std::fprintf( stderr, "Try '%s --help' for more information.\n",
invocation_name );
}
void internal_error( const char * const msg )
{
std::fprintf( stderr, "%s: internal error: %s\n", program_name, msg );
std::exit( 3 );
}
} // end namespace
int main( const int argc, const char * const argv[] )
{
bool verbose = false;
if( argc > 0 ) invocation_name = argv[0];
const Arg_parser::Option options[] =
{
{ 'a', "append", Arg_parser::no },
{ 'b', "block", Arg_parser::yes },
{ 'c', "casual", Arg_parser::maybe },
{ 'h', "help", Arg_parser::no },
{ 'H', "hidden", Arg_parser::no },
{ 'o', 0, Arg_parser::yes },
{ 'q', "quiet", Arg_parser::no },
{ 'u', "uncaught", Arg_parser::no },
{ 'v', "verbose", Arg_parser::no },
{ 'V', "version", Arg_parser::no },
{ 256, "orphan", Arg_parser::no },
{ INT_MIN, "int-min", Arg_parser::no },
{ INT_MAX, "int-max", Arg_parser::no },
{ 0, 0, Arg_parser::no } };
const Arg_parser parser( argc, argv, options );
if( parser.error().size() ) // bad option
{ show_error( parser.error().c_str(), 0, true ); return 1; }
for( int argind = 0; argind < parser.arguments(); ++argind )
{
const int code = parser.code( argind );
if( !code ) break; // no more options
switch( code )
{
case 'a': break; // example, do nothing
case 'b': break; // example, do nothing
case 'c': break; // example, do nothing
case 'h': show_help( verbose ); return 0;
case 'H': break; // example, do nothing
case 'o': break; // example, do nothing
case 'q': verbose = false; break;
// case 'u': break; // intentionally not caught
case 'v': verbose = true; break;
case 'V': show_version(); return 0;
case 256: break; // example, do nothing
case INT_MIN: break; // example, do nothing
case INT_MAX: break; // example, do nothing
default : internal_error( "uncaught option." );
}
} // end process options
for( int argind = 0; argind < parser.arguments(); ++argind )
{
const int code = parser.code( argind );
const char * const arg = parser.argument( argind ).c_str();
if( code ) // option
{
std::printf( "option '%s'", parser.parsed_name( argind ).c_str() );
if( arg[0] ) std::printf( " with argument '%s'", arg );
if( code == INT_MIN || code == INT_MAX ) std::printf( " (code 0x%X)", code );
}
else // non-option
std::printf( "non-option argument '%s'", arg );
std::fputc( '\n', stdout );
}
if( !parser.arguments() ) std::fputs( "Hello, world!\n", stdout );
return 0;
}