I’ve got a large (read: nightmare) method which has grown over the years to support my project’s ever growing list of commandline arguments. I mean several pages of readme docs for brief blurbs per argument.
As I’ve added each feature, I’ve simply “registered” a way of handling that argument by adding a few lines to that method.
However, that method is now unsightly, bug prone, and difficult to understand. Here’s an example of the shorter of the two methods currently handling this:
//All double dash arguments modify global options of the program,
//such as --all --debug --timeout etc.
void consoleParser::wordArgParse(std::vector<criterion *> *results)
{
TCHAR const *compareCurWordArg = curToken.c_str()+2;
if (!_tcsicmp(compareCurWordArg,_T("all")))
{
globalOptions::showall = TRUE;
} else if (!_tcsnicmp(compareCurWordArg,_T("custom"),6))
{
if (curToken[9] == L':')
{
globalOptions::display = curToken.substr(10,curToken.length()-11);
} else
{
globalOptions::display = curToken.substr(9,curToken.length()-10);
}
} else if (*compareCurWordArg == L'c' || *compareCurWordArg == L'C')
{
if (curToken[3] == L':')
{
globalOptions::display = curToken.substr(5,curToken.length()-6);
} else
{
globalOptions::display = curToken.substr(4,curToken.length()-5);
}
} else if (!_tcsicmp(compareCurWordArg,_T("debug")))
{
globalOptions::debug = TRUE;
} else if (!_tcsicmp(compareCurWordArg,L"expand"))
{
globalOptions::expandRegex = false;
} else if (!_tcsicmp(compareCurWordArg,L"fileLook"))
{
globalOptions::display = L"---- #f ----#nCompany: #d#nFile Description: #e#nFile Version: #g"
L"#nProduct Name: #i#nCopyright: #j#nOriginal file name: #k#nFile Size: #u#nCreated Time: #c"
L"#nModified Time: #m#nAccessed Time: #a#nMD5: #5#nSHA1: #1";
} else if (!_tcsicmp(compareCurWordArg,_T("peinfo")))
{
globalOptions::display = _T("[#p] #f");
} else if (!_tcsicmp(compareCurWordArg,L"enable-filesystem-redirector-64"))
{
globalOptions::disable64Redirector = false;
} else if (!_tcsnicmp(compareCurWordArg,_T("encoding"),8))
{
//Performance enhancement -- encoding compare only done once.
compareCurWordArg += 8;
if (!_tcsicmp(compareCurWordArg,_T("acp")))
{
globalOptions::encoding = globalOptions::ENCODING_TYPE_ACP;
} else if (!_tcsicmp(compareCurWordArg,_T("oem")))
{
globalOptions::encoding = globalOptions::ENCODING_TYPE_OEM;
} else if (!_tcsicmp(compareCurWordArg,_T("utf8")))
{
globalOptions::encoding = globalOptions::ENCODING_TYPE_UTF8;
} else if (!_tcsicmp(compareCurWordArg,_T("utf16")))
{
globalOptions::encoding = globalOptions::ENCODING_TYPE_UTF16;
} else
{
throw eMsg(L"Unrecognised encoding word argument!\r\nValid choices are --encodingACP --encodingOEM --encodingUTF8 and --encodingUTF16. Terminate.");
}
} else if (!_tcsnicmp(compareCurWordArg,L"files",5))
{
compareCurWordArg += 5;
if (*compareCurWordArg == L':') compareCurWordArg++;
std::wstring filePath(compareCurWordArg);
globalOptions::regexes.insert(globalOptions::regexes.end(), new filesRegexPlaceHolder);
results->insert(results->end(),new filesRegexPlaceHolder);
boost::algorithm::trim_if(filePath,std::bind2nd(std::equal_to<wchar_t>(),L'"'));
loadFiles(filePath);
} else if (!_tcsicmp(compareCurWordArg,_T("full")))
{
globalOptions::fullPath = TRUE;
} else if (!_tcsicmp(compareCurWordArg,_T("fs32")))
{
globalOptions::disable64Redirector = false;
} else if (!_tcsicmp(compareCurWordArg,_T("long")))
{
globalOptions::display = _T("#t #s #m #f");
globalOptions::summary = TRUE;
} else if (!_tcsnicmp(compareCurWordArg,_T("limit"),5))
{
compareCurWordArg += 5;
if (*compareCurWordArg == _T(':'))
compareCurWordArg++;
globalOptions::lineLimit = _tcstoui64(compareCurWordArg,NULL,10);
if (!globalOptions::lineLimit)
{
std::wcerr << eMsg(L"Warning: You are limiting to infinity lines. Check one of your --limit options!\r\n");
}
} else if (!_tcsicmp(compareCurWordArg,_T("short")))
{
globalOptions::display = _T("#8");
} else if (!_tcsicmp(compareCurWordArg,_T("summary")))
{
globalOptions::summary = TRUE;
} else if (!_tcsicmp(compareCurWordArg,_T("norecursion")))
{
globalOptions::noSubDirs = TRUE;
} else if (!_tcsnicmp(compareCurWordArg,_T("timeout"),7))
{
compareCurWordArg += 7;
if (*compareCurWordArg == _T(':'))
compareCurWordArg++;
globalOptions::timeout = _tcstoul(compareCurWordArg,NULL,10);
if (!globalOptions::timeout)
{
std::wcerr << eMsg(L"Warning: You are limiting to infinite time. Check one of your --timeout options!\r\n");
}
} else if (!_tcsnicmp(compareCurWordArg,_T("tx"),2))
{
compareCurWordArg += 2;
if (*compareCurWordArg == _T(':'))
compareCurWordArg++;
globalOptions::timeout = _tcstoul(compareCurWordArg,NULL,10);
if (!globalOptions::timeout)
{
std::wcerr << eMsg(L"Warning: You are limiting to infinite time. Check one of your --timeout options!\r\n");
}
} else
{
throw eMsg(L"Could not understand word argument! Ensure all of your directives are spelled correctly. Terminate.");
}
}
I’d post the long one but it’s over 500 lines.
Are there better ways of handling this particular problem or should I just leave it as a long method?
EDIT: I’m not looking for a tokenizing library — I already did the dirty work on that. I’m curious if it would make sense to make stub methods out of the larger dirty method.
Billy3
I’m sure that there’s an equivalent of getopt(3) function for Windows.
Here’s the first hit from Google – Pete Wilson.
Or you can look into Boost Program Options for a decent C++ library.