getopt.cpp

#if _MSC_VER >= 1400
# pragma warning(disable : 4996)
#endif

// included header files
#include <assert.h>
#include <errno.h>
#include <cstdlib>
#include <string.h>
#include <stdarg.h>
#include <stdio.h>
#include <iostream>

#include "utils.hpp"
#include "getopt.hpp"

namespace Util {

    // https://raw.githubusercontent.com/skeeto/getopt/master/getopt.h
    int optind = 0;
    int opterr = 1;
    int optopt;
    int optpos = 1;
    const char* optarg;

	/* A minimal POSIX getopt() implementation in ANSI C
	 *
	 * This is free and unencumbered software released into the public domain.
	 *
	 * This implementation supports the convention of resetting the option
	 * parser by assigning optind to 0. This resets the internal state
	 * appropriately.
	 *
	 * Ref: http://pubs.opengroup.org/onlinepubs/9699919799/functions/getopt.html
	 */

	int getopt(int argc, char * const argv[], const char *optstring)
	{
		const char *arg;
		(void)argc;

		/* Reset? */
		if (optind == 0) {
			optind = 1;
			optpos = 1;
		}

		arg = argv[optind];
		if (arg && strcmp(arg, "--") == 0) {
			optind++;
			return -1;
		} else if (!arg || arg[0] != '-' || !isalnum(arg[1])) {
			return -1;
		} else {
			const char *opt = strchr(optstring, arg[optpos]);
			optopt = arg[optpos];
			if (!opt) {
				if (opterr && *optstring != ':')
					fprintf(stderr, "%s: illegal option: %c\n", argv[0], optopt);
				return '?';
			} else if (opt[1] == ':') {
				if (arg[optpos + 1]) {
					optarg = (char *)arg + optpos + 1;
					optind++;
					optpos = 1;
					return optopt;
				} else if (argv[optind + 1]) {
					optarg = (char *)argv[optind + 1];
					optind += 2;
					optpos = 1;
					return optopt;
				} else {
					if (opterr && *optstring != ':')
						fprintf(stderr,
								"%s: option requires an argument: %c\n",
								argv[0], optopt);
					return *optstring == ':' ? ':' : '?';
				}
			} else {
				if (!arg[++optpos]) {
					optind++;
					optpos = 1;
				}
				return optopt;
			}
		}
	}

// *****************************************************************************
// class Getopt
    Getopt::Getopt()
        : errcnt_(0)
    {
    }

    Getopt::~Getopt()
    {
    }

    int Getopt::getopt(int argc, char* const argv[], const std::string& optstring)
    {
        progname_ = Util::basename(argv[0]);
        Util::optind = 0; // reset the Util::Getopt scanner

        for (;!errcnt_;) {
            int c = Util::getopt(argc, argv, optstring.c_str());
            if (c == -1) {
                break;
            }
            errcnt_ += option(c, Util::optarg == 0 ? "" : Util::optarg, Util::optopt);
            if (c == '?' ) {
                break;
            }
        }
        for (int i = Util::optind; i < argc; i++) {
            errcnt_ += nonoption(argv[i]);
        }

        return errcnt_;
    }

    int Getopt::nonoption(const std::string& /*argv*/)
    {
        return 0;
    }

} // namespace Util