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 template<class T> inline
29 std::string to_string(T&& value)
31 return std::to_string(std::forward<T>(value));
33 inline std::string const& to_string(std::string& value)
37 inline std::string const& to_string(std::string const& value)
41 inline std::string to_string(std::string&& value)
43 return std::move(value);
48 template <class T> XBT_PUBLIC T const& getConfig(const char* name);
50 extern template XBT_PUBLIC int const& getConfig<int>(const char* name);
51 extern template XBT_PUBLIC double const& getConfig<double>(const char* name);
52 extern template XBT_PUBLIC bool const& getConfig<bool>(const char* name);
53 extern template XBT_PUBLIC std::string const& getConfig<std::string>(const char* name);
57 /** Register a configuration flag
59 * @param name name of the option
60 * @param description Description of the option
61 * @param value Initial/default value
62 * @param callback called with the option value
65 XBT_PUBLIC void declareFlag(const char* name, const char* description, T value,
66 std::function<void(const T&)> callback = std::function<void(const T&)>());
68 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, int value,
69 std::function<void(int const&)> callback);
70 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, double value,
71 std::function<void(double const&)> callback);
72 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, bool value,
73 std::function<void(bool const&)> callback);
74 extern template XBT_PUBLIC void declareFlag(const char* name, const char* description, std::string value,
75 std::function<void(std::string const&)> callback);
79 XBT_PUBLIC void alias(const char* realname, const char* aliasname);
82 void alias(std::initializer_list<const char*> names)
84 auto i = names.begin();
85 for (++i; i != names.end(); ++i)
86 alias(*names.begin(), *i);
89 /** Bind a variable to configuration flag
91 * @param value Bound variable
92 * @param name Flag name
93 * @param description Option description
96 void bindFlag(T& value, const char* name, const char* description)
98 declareFlag<T>(name, description, value, [&value](T const& val) {
104 void bindFlag(T& value, std::initializer_list<const char*> names, const char* description)
106 bindFlag(value, *names.begin(), description);
110 /** Bind a variable to configuration flag
114 * simgrid::config::bindFlag(a, "x", [](int x) {
115 * if (x < x_min || x => x_max)
116 * throw std::range_error("must be in [x_min, x_max)")
120 // F is a checker, F : T& -> ()
121 template <class T, class F>
122 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
123 bindFlag(T& value, const char* name, const char* description, F callback)
125 declareFlag(name, description, value, std::function<void(const T&)>([&value, callback](const T& val) {
127 value = std::move(val);
131 template <class T, class F>
132 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
133 bindFlag(T& value, std::initializer_list<const char*> names, const char* description, F callback)
135 bindFlag(value, *names.begin(), description);
139 template <class T, class F>
140 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
141 bindFlag(T& value, const char* name, const char* description, std::map<T, std::string> valid_values, F callback)
143 declareFlag(name, description, value,
144 std::function<void(const T&)>([&value, name, valid_values, callback](const T& val) {
147 for (auto kv : valid_values) {
151 if (not found || std::string(val) == "help") {
153 if (std::string(val) == "help")
154 mesg = std::string("\nPossible values for option ") + name + ":\n";
156 mesg = std::string("\nInvalid value '") + val + "' for option " + name + ". Possible values:\n";
157 for (auto kv : valid_values)
158 mesg += " - '" + std::string(kv.first) + "': " + kv.second +
159 (kv.first == value ? " <=== DEFAULT" : "") + "\n";
160 xbt_die("%s", mesg.c_str());
162 value = std::move(val);
165 /** Bind a variable to configuration flag
169 * simgrid::config::bindFlag(a, "x", [](int x) { return x > 0; });
172 // F is a predicate, F : T const& -> bool
173 template<class T, class F>
174 typename std::enable_if<std::is_same<
176 decltype( std::declval<F>()(std::declval<const T&>()) )
177 >::value, void>::type
178 bindFlag(T& value, const char* name, const char* description,
181 declareFlag(name, description, value, std::function<void(const T&)>([&value, callback](const T& val) {
182 if (not callback(val))
183 throw std::range_error("invalid value.");
184 value = std::move(val);
188 /** A variable bound to a CLI option
191 * static simgrid::config::flag<int> answer("answer", "Expected answer", 42);
192 * static simgrid::config::flag<std::string> name("name", "Ford Perfect", "John Doe");
193 * static simgrid::config::flag<double> gamma("gamma", "Gamma factor", 1.987);
203 * @param name Flag name
204 * @param desc Flag description
205 * @param value Flag initial/default value
207 Flag(const char* name, const char* desc, T value) : value_(value)
209 simgrid::config::bindFlag(value_, name, desc);
212 /** Constructor taking an array of aliases as name */
213 Flag(std::initializer_list<const char*> names, const char* desc, T value) : value_(value)
215 simgrid::config::bindFlag(value_, names, desc);
218 /* A constructor accepting a callback that will be passed the parameter.
219 * It can either return a boolean (informing whether the parameter is valid), or returning void.
222 Flag(const char* name, const char* desc, T value, F callback) : value_(value)
224 simgrid::config::bindFlag(value_, name, desc, std::move(callback));
227 /* A constructor accepting a map of valid values -> their description,
228 * and producing an informative error message when an invalid value is passed, or when help is passed as a value.
231 Flag(const char* name, const char* desc, T value, std::map<T, std::string> valid_values, F callback) : value_(value)
233 simgrid::config::bindFlag(value_, name, desc, std::move(valid_values), std::move(callback));
237 Flag(Flag const&) = delete;
238 Flag& operator=(Flag const&) = delete;
240 // Get the underlying value:
241 T& get() { return value_; }
242 T const& get() const { return value_; }
244 // Implicit conversion to the underlying type:
245 operator T&() { return value_; }
246 operator T const&() const{ return value_; }
248 // Basic interop with T:
250 Flag& operator=(U const& that) { value_ = that; return *this; }
252 Flag& operator=(U && that) { value_ = that; return *this; }
254 bool operator==(U const& that) const { return value_ == that; }
256 bool operator!=(U const& that) const { return value_ != that; }
258 bool operator<(U const& that) const { return value_ < that; }
260 bool operator>(U const& that) const { return value_ > that; }
262 bool operator<=(U const& that) const { return value_ <= that; }
264 bool operator>=(U const& that) const { return value_ >= that; }
269 XBT_PUBLIC std::string xbt_cfg_get_string(const char* name);