options.cc

//  Copyright (c) 2010-2018 David Caldwell <david@porkrind.org>
//  Licenced under the GPL 3.0 or any later version. See LICENSE file for details.

#include "options.h"
#include <vector>
#include <string>
#include <algorithm>
#include <stdio.h>

using namespace std;

class option_match {
    public: string &lopt, &sopt;
            option_match(string &lopt, string &sopt) : lopt(lopt), sopt(sopt) {}
            bool operator()(string s) {
                return s == "--"+lopt ||
                       s.find("--"+lopt+"=") == 0 ||
                       sopt.size() && s[0] == '-' && s[1] != '-' && s.find(sopt) != s.npos;
            }
};

options::options(int c, char **v, size_t _end)
{
    v++; c--;
    end = _end;
    for (int i=0; i<c; i++)
        if (string(v[i]) == "--" && end == (size_t) -1)
            end = i;
        else
            args.push_back(v[i]);
    if (end == (size_t) -1)
        end = args.size();
}

bool options::get(string long_opt, char short_opt_char, arg_type type)
{
    string short_opt; short_opt += short_opt_char;
    arg="";
    argm.clear();
    vector<string>::iterator o = args.begin();
    while(1) {
        o = find_if(o, args.begin()+end, option_match(long_opt, short_opt));
        if (o == args.begin()+end)
            break;

        vector<string>::iterator argi;
        string opt = *o;
        bool islong = opt.find("--") == 0;
        if (!islong) {
            o->erase(o->find(short_opt),1); // Remove option from bundle.
            if (o->size() == 1)
                goto drop_arg;
            argi = o+1;
        } else {
          drop_arg:
            o = args.erase(o);
            end--;
            argi = o;
        }

#define opt_name()  (islong ? "--"+long_opt : "-"+short_opt)

        string val;
        if (type == arg_none) {
            if (islong && opt.find("=") != opt.npos) {
                bad.push_back("\""+opt_name()+"\" does not take an argument");
                continue;
            }
            val = opt;
        }
        if (type == arg_required) {
            size_t vo;
            if (islong && (vo = opt.find('=')) != opt.npos) {
                val = opt.substr(vo+1);
            } else {
                if (argi == args.begin()+end) {
                    bad.push_back("missing argument for "+opt_name());
                    continue;
                }
                val = *argi;
                argi = args.erase(argi);
                end--;
            }
        }
        argm.push_back(val);
        arg = val;
    }
    return argm.size();
}

bool options::get(string long_opt, arg_type type)
{
    return get(long_opt, 0, type);
}

bool options::bad_args()
{
    bool is_bad = false;
    for (vector<string>::iterator ba = bad.begin(); ba != bad.end(); ba++)
        fprintf(stderr, "%s\n", ba->c_str());

    for (vector<string>::iterator a = args.begin(); a != args.begin()+end; a++)
        if (a->size() && a->at(0) == '-') {
            fprintf(stderr, "Unknown argument \"%s\"\n", a->c_str());
            is_bad = true;
        }
    return bad.size() || is_bad;
}


#ifdef TEST
// test-build-flags: -x c++ -lstdc++
int main(int c, char **v)
{
    options o(c, v);
    if (o.get("long",           "long only option"))               { printf("Long "); }
    if (o.get("short",    's',  "short option"))                   { printf("Short "); }
    if (o.get("count",    'c',  "counting option"))                { printf("Count=%zd ", o.argm.size()); }
    if (o.get("long-arg",       "long arg option",  arg_required)) { printf("Long-Arg=%s ", o.arg.c_str()); }
    if (o.get("short-arg",'a',  "short arg option", arg_required)) { printf("Short-Arg=%s ", o.arg.c_str()); }
    if (o.get("help",           "Show Help"))                      { o.usage("", EXIT_SUCCESS); }

    if (o.bad_args()) printf("Bad args! ");
    if (o.args.size())
        printf("Extra:");
    for (vector<string>::iterator a = o.args.begin(); a != o.args.end(); a++)
        printf(" %s", a->c_str());
    printf("\n");
}

/* test-cases:
   * --long --short -c -c -c --count --long-arg=david -a rules
     > Long Short Count=4 Long-Arg=david Short-Arg=rules 
   * --short-arg=hi -c 1 --short 2 --count
     > Short Count=2 Short-Arg=hi Extra: 1 2
   * bundling -ccaccs short
     > Short Count=4 Short-Arg=short Extra: bundling
   * --long-arg no=
     > Long-Arg=no= 
   * --long-arg
    2> missing argument for --long-arg
     > Bad args! 
   * --short-arg
    2> missing argument for --short-arg
     > Bad args! 
   * -a
    2> missing argument for -a
     > Bad args! 
   * --long=short
    2> "--long" does not take an argument
     > Bad args! 
   * -a=short
    2> missing argument for -a
    2> Unknown argument "-=hort"
     > Short Bad args! Extra: -=hort
   * -a 1 -- -s -ccc --long-arg
     > Short-Arg=1 Extra: -s -ccc --long-arg
   * -a -- 1 -s -ccc --long-arg
    2> missing argument for -a
     > Bad args! Extra: 1 -s -ccc --long-arg
*/
#endif