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 map<string, Option*>::iterator I = getOpts().find("");
53 Handler = I != getOpts().end() ? I->second : 0;
55 } else { // We start with a - or --, eat dashes
57 while (*ArgName == '-') ++ArgName; // Eat leading dashes
59 const char *ArgNameEnd = ArgName;
60 while (*ArgNameEnd && *ArgNameEnd != '=') ++ArgNameEnd; // Scan till end
63 if (*Value) // If we have an equals sign...
64 ++Value; // Advance to value...
67 // Extract arg name part
68 map<string, Option*>::iterator I = getOpts().find(string(ArgName, ArgNameEnd));
69 Handler = I != getOpts().end() ? I->second : 0;
74 cerr << "Unknown command line argument '" << argv[i] << "'. Try: "
75 << argv[0] << " --help\n'";
80 // Enforce value requirements
81 switch (Handler->getValueExpectedFlag()) {
83 if (Value == 0 || *Value == 0) { // No value specified?
84 if (i+1 < argc) { // Steal the next argument, like for '-o filename'
87 ErrorParsing = Handler->error(" requires a value!");
94 ErrorParsing = Handler->error(" does not allow a value! '" +
95 string(Value) + "' specified.");
99 case ValueOptional: break;
100 default: cerr << "Bad ValueMask flag! CommandLine usage error:"
101 << Handler->getValueExpectedFlag() << endl; abort();
104 // Run the handler now!
105 ErrorParsing |= Handler->addOccurance(ArgName, Value);
108 // Loop over args and make sure all required args are specified!
109 for (map<string, Option*>::iterator I = getOpts().begin(),
110 E = getOpts().end(); I != E; ++I) {
111 switch (I->second->getNumOccurancesFlag()) {
114 if (I->second->getNumOccurances() == 0)
115 I->second->error(" must be specified at least once!");
122 // Free all of the memory allocated to the vector. Command line options may
123 // only be processed once!
126 // If we had an error processing our arguments, don't let the program execute
127 if (ErrorParsing) exit(1);
130 //===----------------------------------------------------------------------===//
131 // Option Base class implementation
133 Option::Option(const char *argStr, const char *helpStr, int flags)
134 : NumOccurances(0), Flags(flags), ArgStr(argStr), HelpStr(helpStr) {
135 AddArgument(ArgStr, this);
138 bool Option::error(string Message, const char *ArgName = 0) {
139 if (ArgName == 0) ArgName = ArgStr;
140 cerr << "-" << ArgName << " option" << Message << endl;
144 bool Option::addOccurance(const char *ArgName, const string &Value) {
145 NumOccurances++; // Increment the number of times we have been seen
147 switch (getNumOccurancesFlag()) {
149 if (NumOccurances > 1)
150 return error(": may only occur zero or one times!", ArgName);
153 if (NumOccurances > 1)
154 return error(": must occur exactly one time!", ArgName);
157 case ZeroOrMore: break;
158 default: return error(": bad num occurances flag value!");
161 return handleOccurance(ArgName, Value);
164 // Return the width of the option tag for printing...
165 unsigned Option::getOptionWidth() const {
166 return std::strlen(ArgStr)+6;
169 void Option::printOptionInfo(unsigned GlobalWidth) const {
170 unsigned L = std::strlen(ArgStr);
171 if (L == 0) return; // Don't print the empty arg like this!
172 cerr << " -" << ArgStr << string(GlobalWidth-L-6, ' ') << " - "
177 //===----------------------------------------------------------------------===//
178 // Boolean/flag command line option implementation
181 bool Flag::handleOccurance(const char *ArgName, const string &Arg) {
182 if (Arg == "" || Arg == "true" || Arg == "TRUE" || Arg == "True" ||
185 } else if (Arg == "false" || Arg == "FALSE" || Arg == "False" || Arg == "0") {
188 return error(": '" + Arg + "' is invalid value for boolean argument! Try 0 or 1");
194 //===----------------------------------------------------------------------===//
195 // Integer valued command line option implementation
197 bool Int::handleOccurance(const char *ArgName, const string &Arg) {
198 const char *ArgStart = Arg.c_str();
200 Value = (int)strtol(ArgStart, &End, 0);
202 return error(": '" + Arg + "' value invalid for integer argument!");
206 //===----------------------------------------------------------------------===//
207 // String valued command line option implementation
209 bool String::handleOccurance(const char *ArgName, const string &Arg) {
214 //===----------------------------------------------------------------------===//
215 // Enum valued command line option implementation
217 void EnumBase::processValues(va_list Vals) {
218 while (const char *EnumName = va_arg(Vals, const char *)) {
219 int EnumVal = va_arg(Vals, int);
220 const char *EnumDesc = va_arg(Vals, const char *);
221 ValueMap.push_back(make_pair(EnumName, // Add value to value map
222 make_pair(EnumVal, EnumDesc)));
226 // registerArgs - notify the system about these new arguments
227 void EnumBase::registerArgs() {
228 for (unsigned i = 0; i < ValueMap.size(); ++i)
229 AddArgument(ValueMap[i].first, this);
232 const char *EnumBase::getArgName(int ID) const {
233 for (unsigned i = 0; i < ValueMap.size(); ++i)
234 if (ID == ValueMap[i].second.first) return ValueMap[i].first;
237 const char *EnumBase::getArgDescription(int ID) const {
238 for (unsigned i = 0; i < ValueMap.size(); ++i)
239 if (ID == ValueMap[i].second.first) return ValueMap[i].second.second;
245 bool EnumValueBase::handleOccurance(const char *ArgName, const string &Arg) {
247 for (i = 0; i < ValueMap.size(); ++i)
248 if (ValueMap[i].first == Arg) break;
249 if (i == ValueMap.size())
250 return error(": unrecognized alternative '"+Arg+"'!");
251 Value = ValueMap[i].second.first;
255 // Return the width of the option tag for printing...
256 unsigned EnumValueBase::getOptionWidth() const {
257 unsigned BaseSize = Option::getOptionWidth();
258 for (unsigned i = 0; i < ValueMap.size(); ++i)
259 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+8);
263 // printOptionInfo - Print out information about this option. The
264 // to-be-maintained width is specified.
266 void EnumValueBase::printOptionInfo(unsigned GlobalWidth) const {
267 Option::printOptionInfo(GlobalWidth);
268 for (unsigned i = 0; i < ValueMap.size(); ++i) {
269 unsigned NumSpaces = GlobalWidth-strlen(ValueMap[i].first)-8;
270 cerr << " =" << ValueMap[i].first << string(NumSpaces, ' ') << " - "
271 << ValueMap[i].second.second;
273 if (i == 0) cerr << " (default)";
278 //===----------------------------------------------------------------------===//
279 // Enum flags command line option implementation
282 bool EnumFlagsBase::handleOccurance(const char *ArgName, const string &Arg) {
283 return EnumValueBase::handleOccurance("", ArgName);
286 unsigned EnumFlagsBase::getOptionWidth() const {
287 unsigned BaseSize = 0;
288 for (unsigned i = 0; i < ValueMap.size(); ++i)
289 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+6);
293 void EnumFlagsBase::printOptionInfo(unsigned GlobalWidth) const {
294 for (unsigned i = 0; i < ValueMap.size(); ++i) {
295 unsigned L = std::strlen(ValueMap[i].first);
296 cerr << " -" << ValueMap[i].first << string(GlobalWidth-L-6, ' ') << " - "
297 << ValueMap[i].second.second;
298 if (i == 0) cerr << " (default)";
304 //===----------------------------------------------------------------------===//
305 // Enum list command line option implementation
308 bool EnumListBase::handleOccurance(const char *ArgName, const string &Arg) {
310 for (i = 0; i < ValueMap.size(); ++i)
311 if (ValueMap[i].first == string(ArgName)) break;
312 if (i == ValueMap.size())
313 return error(": CommandLine INTERNAL ERROR", ArgName);
314 Values.push_back(ValueMap[i].second.first);
318 // Return the width of the option tag for printing...
319 unsigned EnumListBase::getOptionWidth() const {
320 unsigned BaseSize = 0;
321 for (unsigned i = 0; i < ValueMap.size(); ++i)
322 BaseSize = max(BaseSize, std::strlen(ValueMap[i].first)+6);
327 // printOptionInfo - Print out information about this option. The
328 // to-be-maintained width is specified.
330 void EnumListBase::printOptionInfo(unsigned GlobalWidth) const {
331 for (unsigned i = 0; i < ValueMap.size(); ++i) {
332 unsigned L = std::strlen(ValueMap[i].first);
333 cerr << " -" << ValueMap[i].first << string(GlobalWidth-L-6, ' ') << " - "
334 << ValueMap[i].second.second << endl;
339 //===----------------------------------------------------------------------===//
340 // Help option... always automatically provided.
344 // isHidden/isReallyHidden - Predicates to be used to filter down arg lists.
345 inline bool isHidden(pair<string, Option *> &OptPair) {
346 return OptPair.second->getOptionHiddenFlag() >= Hidden;
348 inline bool isReallyHidden(pair<string, Option *> &OptPair) {
349 return OptPair.second->getOptionHiddenFlag() == ReallyHidden;
352 class Help : public Option {
354 const Option *EmptyArg;
355 const bool ShowHidden;
357 virtual bool handleOccurance(const char *ArgName, const string &Arg) {
358 // Copy Options into a vector so we can sort them as we like...
359 vector<pair<string, Option*> > Options;
360 copy(getOpts().begin(), getOpts().end(), back_inserter(Options));
362 // Eliminate Hidden or ReallyHidden arguments, depending on ShowHidden
363 Options.erase(remove_if(Options.begin(), Options.end(),
364 ptr_fun(ShowHidden ? isReallyHidden : isHidden)),
367 // Eliminate duplicate entries in table (from enum flags options, f.e.)
368 set<Option*> OptionSet;
369 for (unsigned i = 0; i < Options.size(); )
370 if (OptionSet.count(Options[i].second) == 0)
371 OptionSet.insert(Options[i++].second); // Add to set
373 Options.erase(Options.begin()+i); // Erase duplicate
377 cerr << "OVERVIEW:" << ProgramOverview << endl;
378 // TODO: Sort options by some criteria
380 cerr << "USAGE: " << ProgramName << " [options]\n\n";
381 // TODO: print usage nicer
383 // Compute the maximum argument length...
385 for_each(Options.begin(), Options.end(),
386 bind_obj(this, &Help::getMaxArgLen));
388 cerr << "OPTIONS:\n";
389 for_each(Options.begin(), Options.end(),
390 bind_obj(this, &Help::printOption));
392 return true; // Displaying help is cause to terminate the program
395 void getMaxArgLen(pair<string, Option *> OptPair) {
396 const Option *Opt = OptPair.second;
397 if (Opt->ArgStr[0] == 0) EmptyArg = Opt; // Capture the empty arg if exists
398 MaxArgLen = max(MaxArgLen, Opt->getOptionWidth());
401 void printOption(pair<string, Option *> OptPair) {
402 const Option *Opt = OptPair.second;
403 Opt->printOptionInfo(MaxArgLen);
407 inline Help(const char *ArgVal, const char *HelpVal, bool showHidden)
408 : Option(ArgVal, HelpVal, showHidden ? Hidden : 0), ShowHidden(showHidden) {
413 Help HelpOp("help", "display available options"
414 " (--help-hidden for more)", false);
415 Help HelpHiddenOpt("help-hidden", "display all available options", true);
417 } // End anonymous namespace