OpenTTD-patches/src/misc/getoptdata.cpp
2019-11-10 17:59:20 +00:00

84 lines
2.7 KiB
C++

/*
* This file is part of OpenTTD.
* OpenTTD 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, version 2.
* OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file getoptdata.cpp Library for parsing command line options. */
#include "../stdafx.h"
#include "getoptdata.h"
#include "../safeguards.h"
/**
* Find the next option.
* @return Function returns one
* - An option letter if it found another option.
* - -1 if option processing is finished. Inspect #argv and #numleft to find the command line arguments.
* - -2 if an error was encountered.
*/
int GetOptData::GetOpt()
{
const OptionData *odata;
char *s = this->cont;
if (s == nullptr) {
if (this->numleft == 0) return -1; // No arguments left -> finished.
s = this->argv[0];
if (*s != '-') return -1; // No leading '-' -> not an option -> finished.
this->argv++;
this->numleft--;
/* Is it a long option? */
for (odata = this->options; odata->flags != ODF_END; odata++) {
if (odata->longname != nullptr && !strcmp(odata->longname, s)) { // Long options always use the entire argument.
this->cont = nullptr;
goto set_optval;
}
}
s++; // Skip leading '-'.
}
/* Is it a short option? */
for (odata = this->options; odata->flags != ODF_END; odata++) {
if (odata->shortname != '\0' && *s == odata->shortname) {
this->cont = (s[1] != '\0') ? s + 1 : nullptr;
set_optval: // Handle option value of *odata .
this->opt = nullptr;
switch (odata->flags) {
case ODF_NO_VALUE:
return odata->id;
case ODF_HAS_VALUE:
case ODF_OPTIONAL_VALUE:
if (this->cont != nullptr) { // Remainder of the argument is the option value.
this->opt = this->cont;
this->cont = nullptr;
return odata->id;
}
/* No more arguments, either return an error or a value-less option. */
if (this->numleft == 0) return (odata->flags == ODF_HAS_VALUE) ? -2 : odata->id;
/* Next argument looks like another option, let's not return it as option value. */
if (odata->flags == ODF_OPTIONAL_VALUE && this->argv[0][0] == '-') return odata->id;
this->opt = this->argv[0]; // Next argument is the option value.
this->argv++;
this->numleft--;
return odata->id;
default: NOT_REACHED();
}
}
}
return -2; // No other ways to interpret the text -> error.
}