1 //===-- CommandLine.cpp - Command line parser implementation --------------===//
3 // This class implements a command line argument processor that is useful when
4 // creating a tool. It provides a simple, minimalistic interface that is easily
5 // extensible and supports nonlocal (library) command line options.
7 // Note that rather than trying to figure out what this code does, you could try
8 // reading the library documentation located in docs/CommandLine.html
10 //===----------------------------------------------------------------------===//
12 #include "llvm/Support/CommandLine.h"
13 #include "llvm/Support/STLExtras.h"
20 // Return the global command line option vector. Making it a function scoped
21 // static ensures that it will be initialized before its first use correctly.
23 static map<string, Option*> &getOpts() {
24 static map<string,Option*> CommandLineOptions;
25 return CommandLineOptions;
28 static void AddArgument(const string &ArgName, Option *Opt) {
29 if (getOpts().find(ArgName) != getOpts().end()) {
30 cerr << "CommandLine Error: Argument '" << ArgName
31 << "' specified more than once!\n";
33 getOpts()[ArgName] = Opt; // Add argument to the argument map!
37 static const char *ProgramName = 0;
38 static const char *ProgramOverview = 0;
40 void cl::ParseCommandLineOptions(int &argc, char **argv,
41 const char *Overview = 0) {
42 ProgramName = argv[0]; // Save this away safe and snug
43 ProgramOverview = Overview;
44 bool ErrorParsing = false;
46 // Loop over all of the arguments... processing them.
47 for (int i = 1; i < argc; ++i) {
49 const char *Value = "";
50 const char *ArgName = "";
51 if (argv[i][0] != '-') { // Unnamed argument?
52 Handler = getOpts()[""];
54 } else { // We start with a - or --, eat dashes
56 while (*ArgName == '-') ++ArgName; // Eat leading dashes
58 const char *ArgNameEnd = ArgName;
59 while (*ArgNameEnd && *ArgNameEnd != '=') ++ArgNameEnd; // Scan till end
62 if (*Value) // If we have an equals sign...
63 ++Value; // Advance to value...
66 string ArgNameStr(ArgName, ArgNameEnd); // Extract arg name part
67 Handler = getOpts()[ArgNameStr];
72 cerr << "Unknown command line argument '" << argv[i] << "'. Try: "
73 << argv[0] << " --help\n'";
78 // Enforce value requirements
79 switch (Handler->getValueExpectedFlag()) {
81 if (Value == 0 || *Value == 0) { // No value specified?
82 if (i+1 < argc) { // Steal the next argument, like for '-o filename'
85 ErrorParsing = Handler->error(" requires a value!");
92 ErrorParsing = Handler->error(" does not allow a value! '" +
93 string(Value) + "' specified.");
98 default: cerr << "Bad ValueMask flag! CommandLine usage error!\n"; abort();
101 // Run the handler now!
102 ErrorParsing |= Handler->addOccurance(ArgName, Value);
105 // Loop over args and make sure all required args are specified!
106 for (map<string, Option*>::iterator I = getOpts().begin(),
107 E = getOpts().end(); I != E; ++I) {
108 switch (I->second->getNumOccurancesFlag()) {
111 if (I->second->getNumOccurances() == 0)
112 I->second->error(" must be specified at least once!");
119 // Free all of the memory allocated to the vector. Command line options may
120 // only be processed once!
123 // If we had an error processing our arguments, don't let the program execute
124 if (ErrorParsing) exit(1);
127 //===----------------------------------------------------------------------===//
128 // Option Base class implementation
130 Option::Option(const char *argStr, const char *helpStr, int flags)
131 : NumOccurances(0), Flags(flags), ArgStr(argStr), HelpStr(helpStr) {
132 AddArgument(ArgStr, this);
135 bool Option::error(string Message, const char *ArgName = 0) {
136 if (ArgName == 0) ArgName = ArgStr;
137 cerr << "-" << ArgName << " option" << Message << endl;
141 bool Option::addOccurance(const char *ArgName, const string &Value) {
142 NumOccurances++; // Increment the number of times we have been seen
144 switch (getNumOccurancesFlag()) {
146 if (NumOccurances > 1)
147 return error(": may only occur zero or one times!", ArgName);
150 if (NumOccurances > 1)
151 return error(": must occur exactly one time!", ArgName);
154 case ZeroOrMore: break;
155 default: return error(": bad num occurances flag value!");
158 return handleOccurance(ArgName, Value);
161 // Return the width of the option tag for printing...
162 unsigned Option::getOptionWidth() const {
163 return std::strlen(ArgStr)+6;
166 void Option::printOptionInfo(unsigned GlobalWidth) const {
167 unsigned L = std::strlen(ArgStr);
168 if (L == 0) return; // Don't print the empty arg like this!
169 cerr << " -" << ArgStr << string(GlobalWidth-L-6, ' ') << " - "
174 //===----------------------------------------------------------------------===//
175 // Boolean/flag command line option implementation
178 bool Flag::handleOccurance(const char *ArgName, const string &Arg) {
179 if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
182 } else if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
185 return error(": '" + Arg + "' is invalid value for boolean argument! Try 0 or 1");
191 //===----------------------------------------------------------------------===//
192 // Integer valued command line option implementation
194 bool Int::handleOccurance(const char *ArgName, const string &Arg) {
195 const char *ArgStart = Arg.c_str();
197 Value = (int)strtol(ArgStart, &End, 0);
199 return error(": '" + Arg + "' value invalid for integer argument!");
203 //===----------------------------------------------------------------------===//
204 // String valued command line option implementation
206 bool String::handleOccurance(const char *ArgName, const string &Arg) {
211 //===----------------------------------------------------------------------===//
212 // Enum valued command line option implementation
214 void EnumBase::processValues(va_list Vals) {
215 while (const char *EnumName = va_arg(Vals, const char *)) {
216 int EnumVal = va_arg(Vals, int);
217 const char *EnumDesc = va_arg(Vals, const char *);
218 ValueMap.push_back(make_pair(EnumName, // Add value to value map
219 make_pair(EnumVal, EnumDesc)));
223 // registerArgs - notify the system about these new arguments
224 void EnumBase::registerArgs() {
225 for (unsigned i = 0; i < ValueMap.size(); ++i)
226 AddArgument(ValueMap[i].first, this);
229 const char *EnumBase::getArgName(int ID) const {
230 for (unsigned i = 0; i < ValueMap.size(); ++i)
231 if (ID == ValueMap[i].second.first) return ValueMap[i].first;
234 const char *EnumBase::getArgDescription(int ID) const {
235 for (unsigned i = 0; i < ValueMap.size(); ++i)
236 if (ID == ValueMap[i].second.first) return ValueMap[i].second.second;
242 bool EnumValueBase::handleOccurance(const char *ArgName, const string &Arg) {
244 for (i = 0; i < ValueMap.size(); ++i)
245 if (ValueMap[i].first == Arg) break;
246 if (i == ValueMap.size())
247 return error(": unrecognized alternative '"+Arg+"'!");
248 Value = ValueMap[i].second.first;
252 // Return the width of the option tag for printing...
253 unsigned EnumValueBase::getOptionWidth() const {
254 unsigned BaseSize = Option::getOptionWidth();
255 for (unsigned i = 0; i < ValueMap.size(); ++i)
256 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+8);
260 // printOptionInfo - Print out information about this option. The
261 // to-be-maintained width is specified.
263 void EnumValueBase::printOptionInfo(unsigned GlobalWidth) const {
264 Option::printOptionInfo(GlobalWidth);
265 for (unsigned i = 0; i < ValueMap.size(); ++i) {
266 unsigned NumSpaces = GlobalWidth-strlen(ValueMap[i].first)-8;
267 cerr << " =" << ValueMap[i].first << string(NumSpaces, ' ') << " - "
268 << ValueMap[i].second.second;
270 if (i == 0) cerr << " (default)";
275 //===----------------------------------------------------------------------===//
276 // Enum flags command line option implementation
279 bool EnumFlagsBase::handleOccurance(const char *ArgName, const string &Arg) {
280 return EnumValueBase::handleOccurance("", ArgName);
283 unsigned EnumFlagsBase::getOptionWidth() const {
284 unsigned BaseSize = 0;
285 for (unsigned i = 0; i < ValueMap.size(); ++i)
286 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+6);
290 void EnumFlagsBase::printOptionInfo(unsigned GlobalWidth) const {
291 for (unsigned i = 0; i < ValueMap.size(); ++i) {
292 unsigned L = std::strlen(ValueMap[i].first);
293 cerr << " -" << ValueMap[i].first << string(GlobalWidth-L-6, ' ') << " - "
294 << ValueMap[i].second.second;
295 if (i == 0) cerr << " (default)";
301 //===----------------------------------------------------------------------===//
302 // Enum list command line option implementation
305 bool EnumListBase::handleOccurance(const char *ArgName, const string &Arg) {
307 for (i = 0; i < ValueMap.size(); ++i)
308 if (ValueMap[i].first == string(ArgName)) break;
309 if (i == ValueMap.size())
310 return error(": CommandLine INTERNAL ERROR", ArgName);
311 Values.push_back(ValueMap[i].second.first);
315 // Return the width of the option tag for printing...
316 unsigned EnumListBase::getOptionWidth() const {
317 unsigned BaseSize = 0;
318 for (unsigned i = 0; i < ValueMap.size(); ++i)
319 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+6);
324 // printOptionInfo - Print out information about this option. The
325 // to-be-maintained width is specified.
327 void EnumListBase::printOptionInfo(unsigned GlobalWidth) const {
328 for (unsigned i = 0; i < ValueMap.size(); ++i) {
329 unsigned L = std::strlen(ValueMap[i].first);
330 cerr << " -" << ValueMap[i].first << string(GlobalWidth-L-6, ' ') << " - "
331 << ValueMap[i].second.second << endl;
336 //===----------------------------------------------------------------------===//
337 // Help option... always automatically provided.
341 // isHidden/isReallyHidden - Predicates to be used to filter down arg lists.
342 inline bool isHidden(pair<string, Option *> &OptPair) {
343 return OptPair.second->getOptionHiddenFlag() >= Hidden;
345 inline bool isReallyHidden(pair<string, Option *> &OptPair) {
346 return OptPair.second->getOptionHiddenFlag() == ReallyHidden;
349 class Help : public Option {
351 const Option *EmptyArg;
352 const bool ShowHidden;
354 virtual bool handleOccurance(const char *ArgName, const string &Arg) {
355 // Copy Options into a vector so we can sort them as we like...
356 vector<pair<string, Option*> > Options;
357 copy(getOpts().begin(), getOpts().end(), back_inserter(Options));
359 // Eliminate Hidden or ReallyHidden arguments, depending on ShowHidden
360 Options.erase(remove_if(Options.begin(), Options.end(),
361 ptr_fun(ShowHidden ? isReallyHidden : isHidden)),
364 // Eliminate duplicate entries in table (from enum flags options, f.e.)
365 set<Option*> OptionSet;
366 for (unsigned i = 0; i < Options.size(); )
367 if (OptionSet.count(Options[i].second) == 0)
368 OptionSet.insert(Options[i++].second); // Add to set
370 Options.erase(Options.begin()+i); // Erase duplicate
374 cerr << "OVERVIEW:" << ProgramOverview << endl;
375 // TODO: Sort options by some criteria
377 cerr << "USAGE: " << ProgramName << " [options]\n\n";
378 // TODO: print usage nicer
380 // Compute the maximum argument length...
382 for_each(Options.begin(), Options.end(),
383 bind_obj(this, &Help::getMaxArgLen));
385 cerr << "OPTIONS:\n";
386 for_each(Options.begin(), Options.end(),
387 bind_obj(this, &Help::printOption));
389 return true; // Displaying help is cause to terminate the program
392 void getMaxArgLen(pair<string, Option *> OptPair) {
393 const Option *Opt = OptPair.second;
394 if (Opt->ArgStr[0] == 0) EmptyArg = Opt; // Capture the empty arg if exists
395 MaxArgLen = max(MaxArgLen, Opt->getOptionWidth());
398 void printOption(pair<string, Option *> OptPair) {
399 const Option *Opt = OptPair.second;
400 Opt->printOptionInfo(MaxArgLen);
404 inline Help(const char *ArgVal, const char *HelpVal, bool showHidden)
405 : Option(ArgVal, HelpVal, showHidden ? Hidden : 0), ShowHidden(showHidden) {
410 Help HelpOp("help", "display available options"
411 " (--help-hidden for more)", false);
412 Help HelpHiddenOpt("help-hidden", "display all available options", true);
414 } // End anonymous namespace