1 /* Copyright (c) 2016-2018. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
14 #include <initializer_list>
18 #include <type_traits>
22 #include <xbt/config.h>
23 #include <xbt/sysdep.h>
28 class XBT_PUBLIC missing_key_error : public std::runtime_error {
30 explicit missing_key_error(const std::string& what)
31 : std::runtime_error(what) {}
32 explicit missing_key_error(const char* what)
33 : std::runtime_error(what) {}
34 ~missing_key_error() override;
37 template<class T> inline
38 std::string to_string(T&& value)
40 return std::to_string(std::forward<T>(value));
42 inline std::string const& to_string(std::string& value)
46 inline std::string const& to_string(std::string const& value)
50 inline std::string to_string(std::string&& value)
52 return std::move(value);
57 template <class T> XBT_PUBLIC T const& getConfig(const char* name);
59 extern template XBT_PUBLIC int const& getConfig<int>(const char* name);
60 extern template XBT_PUBLIC double const& getConfig<double>(const char* name);
61 extern template XBT_PUBLIC bool const& getConfig<bool>(const char* name);
62 extern template XBT_PUBLIC std::string const& getConfig<std::string>(const char* name);
66 /** Register a configuration flag
68 * @param name name of the option
69 * @param description Description of the option
70 * @param value Initial/default value
71 * @param callback called with the option value
74 XBT_PUBLIC void declareFlag(const char* name, const char* description, T value,
75 std::function<void(const T&)> callback = std::function<void(const T&)>());
77 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, int value,
78 std::function<void(int const&)> callback);
79 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, double value,
80 std::function<void(double const&)> callback);
81 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, bool value,
82 std::function<void(bool const&)> callback);
83 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, std::string value,
84 std::function<void(std::string const&)> callback);
88 XBT_PUBLIC void alias(const char* realname, const char* aliasname);
91 void alias(std::initializer_list<const char*> names)
93 auto i = names.begin();
94 for (++i; i != names.end(); ++i)
95 alias(*names.begin(), *i);
98 /** Bind a variable to configuration flag
100 * @param value Bound variable
101 * @param name Flag name
102 * @param description Option description
105 void bindFlag(T& value, const char* name, const char* description)
107 declareFlag<T>(name, description, value, [&value](T const& val) {
113 void bindFlag(T& value, std::initializer_list<const char*> names, const char* description)
115 bindFlag(value, *names.begin(), description);
119 /** Bind a variable to configuration flag
123 * simgrid::config::bindFlag(a, "x", [](int x) {
124 * if (x < x_min || x => x_max)
125 * throw std::range_error("must be in [x_min, x_max)")
129 // F is a checker, F : T& -> ()
130 template<class T, class F>
131 typename std::enable_if<std::is_same<
133 decltype( std::declval<F>()(std::declval<const T&>()) )
134 >::value, void>::type
135 bindFlag(T& value, std::initializer_list<const char*> names, const char* description,
138 bindFlag(value, *names.begin(), description);
142 template<class T, class F>
143 typename std::enable_if<std::is_same<
145 decltype( std::declval<F>()(std::declval<const T&>()) )
146 >::value, void>::type
147 bindFlag(T& value, const char* name, const char* description,
150 declareFlag(name, description, value,
151 std::function<void(const T&)>([&value,callback](const T& val) {
153 value = std::move(val);
157 template <class T, class F>
158 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
159 bindFlag(T& value, const char* name, const char* description, std::map<T, std::string> valid_values, F callback)
161 declareFlag(name, description, value,
162 std::function<void(const T&)>([&value, name, valid_values, callback](const T& val) {
165 for (auto kv : valid_values) {
169 if (not found || std::string(val) == "help") {
171 if (std::string(val) == "help")
172 mesg = std::string("\nPossible values for option ") + name + ":\n";
174 mesg = std::string("\nInvalid value '") + val + "' for option " + name + ". Possible values:\n";
175 for (auto kv : valid_values)
176 mesg += " - '" + std::string(kv.first) + "': " + kv.second +
177 (kv.first == value ? " <=== DEFAULT" : "") + "\n";
178 xbt_die("%s", mesg.c_str());
180 value = std::move(val);
183 /** Bind a variable to configuration flag
187 * simgrid::config::bindFlag(a, "x", [](int x) { return x > 0; });
190 // F is a predicate, F : T const& -> bool
191 template<class T, class F>
192 typename std::enable_if<std::is_same<
194 decltype( std::declval<F>()(std::declval<const T&>()) )
195 >::value, void>::type
196 bindFlag(T& value, const char* name, const char* description,
199 declareFlag(name, description, value, std::function<void(const T&)>([&value, callback](const T& val) {
200 if (not callback(val))
201 throw std::range_error("invalid value.");
202 value = std::move(val);
206 /** A variable bound to a CLI option
209 * static simgrid::config::flag<int> answer("answer", "Expected answer", 42);
210 * static simgrid::config::flag<std::string> name("name", "Ford Perfect", "John Doe");
211 * static simgrid::config::flag<double> gamma("gamma", "Gamma factor", 1.987);
221 * @param name Flag name
222 * @param desc Flag description
223 * @param value Flag initial/default value
225 Flag(const char* name, const char* desc, T value) : value_(value)
227 simgrid::config::bindFlag(value_, name, desc);
230 /* A constructor accepting a callback that will be passed the parameter.
231 * It can either return a boolean (informing whether the parameter is valid), or returning void.
234 Flag(const char* name, const char* desc, T value, F callback) : value_(value)
236 simgrid::config::bindFlag(value_, name, desc, std::move(callback));
239 /* A constructor accepting a map of valid values -> their description,
240 * and producing an informative error message when an invalid value is passed, or when help is passed as a value.
243 Flag(const char* name, const char* desc, T value, std::map<T, std::string> valid_values, F callback) : value_(value)
245 simgrid::config::bindFlag(value_, name, desc, std::move(valid_values), std::move(callback));
249 Flag(Flag const&) = delete;
250 Flag& operator=(Flag const&) = delete;
252 // Get the underlying value:
253 T& get() { return value_; }
254 T const& get() const { return value_; }
256 // Implicit conversion to the underlying type:
257 operator T&() { return value_; }
258 operator T const&() const{ return value_; }
260 // Basic interop with T:
262 Flag& operator=(U const& that) { value_ = that; return *this; }
264 Flag& operator=(U && that) { value_ = that; return *this; }
266 bool operator==(U const& that) const { return value_ == that; }
268 bool operator!=(U const& that) const { return value_ != that; }
270 bool operator<(U const& that) const { return value_ < that; }
272 bool operator>(U const& that) const { return value_ > that; }
274 bool operator<=(U const& that) const { return value_ <= that; }
276 bool operator>=(U const& that) const { return value_ >= that; }
281 XBT_PUBLIC std::string xbt_cfg_get_string(const char* name);