source/core/getopt.cpp

   1 /* $Id$
   2
   3 This file is part of libmspcore
   4 Copyright © 2006-2009, 2011 Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "getopt.h"
   9
  10 using namespace std;
  11
  12 namespace Msp {
  13
  14 GetOpt::~GetOpt()
  15 {
  16         for(list<OptBase *>::iterator i=opts.begin(); i!=opts.end(); ++i)
  17                 delete *i;
  18 }
  19
  20 GetOpt::OptBase &GetOpt::get_option(char s)
  21 {
  22         for(list<OptBase *>::iterator i=opts.begin(); i!=opts.end(); ++i)
  23                 if((*i)->get_short()==s)
  24                         return **i;
  25         throw UsageError(string("Unknown option -")+s);
  26 }
  27
  28 GetOpt::OptBase &GetOpt::get_option(const string &l)
  29 {
  30         for(list<OptBase *>::iterator i=opts.begin(); i!=opts.end(); ++i)
  31                 if((*i)->get_long()==l)
  32                         return **i;
  33         throw UsageError(string("Unknown option --")+l);
  34 }
  35
  36 void GetOpt::operator()(unsigned argc, const char *const *argv)
  37 {
  38         unsigned i = 1;
  39         for(; i<argc;)
  40         {
  41                 if(argv[i][0]=='-')
  42                 {
  43                         if(argv[i][1]=='-')
  44                         {
  45                                 if(!argv[i][2])
  46                                         break;
  47
  48                                 i += process_long(argv+i);
  49                         }
  50                         else
  51                                 i += process_short(argv+i);
  52                 }
  53                 else
  54                         args.push_back(argv[i++]);
  55         }
  56
  57         for(; i<argc; ++i)
  58                 args.push_back(argv[i]);
  59 }
  60
  61 unsigned GetOpt::process_long(const char *const *argp)
  62 {
  63         // Skip the --
  64         const char *arg = argp[0]+2;
  65
  66         // See if the argument contains an =
  67         unsigned equals = 0;
  68         for(; arg[equals] && arg[equals]!='='; ++equals) ;
  69
  70         OptBase &opt = get_option(string(arg, equals));
  71
  72         if(arg[equals])
  73                 // Process the part after the = as option argument
  74                 opt.process(arg+equals+1);
  75         else if(opt.get_arg_type()==REQUIRED_ARG)
  76         {
  77                 if(!argp[1])
  78                         throw UsageError("Premature end of arguments");
  79
  80                 // Process the next argument as option argument
  81                 opt.process(argp[1]);
  82                 return 2;
  83         }
  84         else
  85                 opt.process();
  86
  87         return 1;
  88 }
  89
  90 unsigned GetOpt::process_short(const char *const *argp)
  91 {
  92         // Skip the -
  93         const char *arg = argp[0]+1;
  94
  95         // Loop through all characters in the argument
  96         for(; *arg; ++arg)
  97         {
  98                 OptBase &opt = get_option(*arg);
  99
 100                 if(arg[1] && opt.get_arg_type()!=NO_ARG)
 101                 {
 102                         // Need an option argument and we have characters left - use them
 103                         opt.process(arg+1);
 104                         return 1;
 105                 }
 106                 else if(opt.get_arg_type()==REQUIRED_ARG)
 107                 {
 108                         if(!argp[1])
 109                                 throw UsageError("Premature end of arguments");
 110
 111                         // Use the next argument as option argument
 112                         opt.process(argp[1]);
 113                         return 2;
 114                 }
 115                 else
 116                         opt.process();
 117         }
 118
 119         return 1;
 120 }
 121
 122 string GetOpt::generate_usage(const string &argv0) const
 123 {
 124         ostringstream line;
 125
 126         line<<argv0;
 127         for(list<OptBase *>::const_iterator i=opts.begin(); i!=opts.end(); ++i)
 128         {
 129                 line<<" [";
 130                 if((*i)->get_short())
 131                 {
 132                         line<<'-'<<(*i)->get_short();
 133                         if(!(*i)->get_long().empty())
 134                                 line<<'|';
 135                         else if((*i)->get_arg_type()==OPTIONAL_ARG)
 136                                 line<<'['<<(*i)->get_metavar()<<']';
 137                         else if((*i)->get_arg_type()==REQUIRED_ARG)
 138                                 line<<' '<<(*i)->get_metavar();
 139                 }
 140                 if(!(*i)->get_long().empty())
 141                 {
 142                         line<<"--"<<(*i)->get_long();
 143
 144                         if((*i)->get_arg_type()==OPTIONAL_ARG)
 145                                 line<<"[="<<(*i)->get_metavar()<<']';
 146                         else if((*i)->get_arg_type()==REQUIRED_ARG)
 147                                 line<<'='<<(*i)->get_metavar();
 148                 }
 149                 line<<']';
 150         }
 151
 152         return line.str();
 153 }
 154
 155 string GetOpt::generate_help() const
 156 {
 157         bool any_short = false;
 158         for(list<OptBase *>::const_iterator i=opts.begin(); (!any_short && i!=opts.end()); ++i)
 159                 any_short = (*i)->get_short();
 160
 161         string::size_type maxw = 0;
 162         list<string> switches;
 163         for(list<OptBase *>::const_iterator i=opts.begin(); i!=opts.end(); ++i)
 164         {
 165                 ostringstream swtch;
 166                 if((*i)->get_short())
 167                 {
 168                         swtch<<'-'<<(*i)->get_short();
 169                         if(!(*i)->get_long().empty())
 170                                 swtch<<", ";
 171                         else if((*i)->get_arg_type()==OPTIONAL_ARG)
 172                                 swtch<<'['<<(*i)->get_metavar()<<']';
 173                         else if((*i)->get_arg_type()==REQUIRED_ARG)
 174                                 swtch<<' '<<(*i)->get_metavar();
 175                 }
 176                 else if(any_short)
 177                         swtch<<"    ";
 178                 if(!(*i)->get_long().empty())
 179                 {
 180                         swtch<<"--"<<(*i)->get_long();
 181
 182                         if((*i)->get_arg_type()==OPTIONAL_ARG)
 183                                 swtch<<"[="<<(*i)->get_metavar()<<']';
 184                         else if((*i)->get_arg_type()==REQUIRED_ARG)
 185                                 swtch<<'='<<(*i)->get_metavar();
 186                 }
 187                 switches.push_back(swtch.str());
 188                 maxw = max(maxw, switches.back().size());
 189         }
 190
 191         string result;
 192         list<string>::const_iterator j = switches.begin();
 193         for(list<OptBase *>::const_iterator i=opts.begin(); i!=opts.end(); ++i, ++j)
 194         {
 195                 result += "  "+*j;
 196                 result += string(maxw+2-j->size(), ' ');
 197                 result += (*i)->get_help();
 198                 result += '\n';
 199         }
 200
 201         return result;
 202 }
 203
 204
 205 GetOpt::OptBase::OptBase(char s, const std::string &l, ArgType a):
 206         shrt(s),
 207         lng(l),
 208         arg_type(a),
 209         seen_count(0),
 210         metavar("ARG")
 211 { }
 212
 213 GetOpt::OptBase &GetOpt::OptBase::set_help(const string &h)
 214 {
 215         help = h;
 216         return *this;
 217 }
 218
 219 GetOpt::OptBase &GetOpt::OptBase::set_help(const string &h, const string &m)
 220 {
 221         help = h;
 222         metavar = m;
 223         return *this;
 224 }
 225
 226 void GetOpt::OptBase::process()
 227 {
 228         if(arg_type==REQUIRED_ARG)
 229                 throw UsageError("--"+lng+" requires an argument");
 230         ++seen_count;
 231
 232         store();
 233 }
 234
 235 void GetOpt::OptBase::process(const string &arg)
 236 {
 237         if(arg_type==NO_ARG)
 238                 throw UsageError("--"+lng+" takes no argument");
 239         ++seen_count;
 240
 241         store(arg);
 242 }
 243
 244 } // namespace Msp