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& get_config(const char* name);
50 extern template XBT_PUBLIC int const& get_config<int>(const char* name);
51 extern template XBT_PUBLIC double const& get_config<double>(const char* name);
52 extern template XBT_PUBLIC bool const& get_config<bool>(const char* name);
53 extern template XBT_PUBLIC std::string const& get_config<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 declare_flag(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 declare_flag(const char* name, const char* description, int value,
69 std::function<void(int const&)> callback);
70 extern template XBT_PUBLIC void declare_flag(const char* name, const char* description, double value,
71 std::function<void(double const&)> callback);
72 extern template XBT_PUBLIC void declare_flag(const char* name, const char* description, bool value,
73 std::function<void(bool const&)> callback);
74 extern template XBT_PUBLIC void declare_flag(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, std::initializer_list<const char*> aliases);
81 /** Bind a variable to configuration flag
83 * @param value Bound variable
84 * @param name Flag name
85 * @param description Option description
87 template <class T> void bind_flag(T& value, const char* name, const char* description)
89 declare_flag<T>(name, description, value, [&value](T const& val) { value = val; });
93 void bind_flag(T& value, const char* name, std::initializer_list<const char*> aliases, const char* description)
95 bind_flag(value, name, description);
96 alias(name, std::move(aliases));
99 /** Bind a variable to configuration flag
103 * simgrid::config::bind_flag(a, "x", [](int x) {
104 * if (x < x_min || x => x_max)
105 * throw std::range_error("must be in [x_min, x_max)")
109 // F is a checker, F : T& -> ()
110 template <class T, class F>
111 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
112 bind_flag(T& value, const char* name, const char* description, F callback)
114 declare_flag(name, description, value, std::function<void(const T&)>([&value, callback](const T& val) {
116 value = std::move(val);
120 template <class T, class F>
121 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
122 bind_flag(T& value, const char* name, std::initializer_list<const char*> aliases, const char* description, F callback)
124 bind_flag(value, name, description, std::move(callback));
125 alias(name, std::move(aliases));
128 template <class T, class F>
129 typename std::enable_if<std::is_same<void, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
130 bind_flag(T& value, const char* name, const char* description, std::map<T, std::string> valid_values, F callback)
132 declare_flag(name, description, value,
133 std::function<void(const T&)>([&value, name, valid_values, callback](const T& val) {
136 for (auto kv : valid_values) {
140 if (not found || std::string(val) == "help") {
142 if (std::string(val) == "help")
143 mesg = std::string("\nPossible values for option ") + name + ":\n";
145 mesg = std::string("\nInvalid value '") + val + "' for option " + name + ". Possible values:\n";
146 for (auto kv : valid_values)
147 mesg += " - '" + std::string(kv.first) + "': " + kv.second +
148 (kv.first == value ? " <=== DEFAULT" : "") + "\n";
149 xbt_die("%s", mesg.c_str());
151 value = std::move(val);
154 /** Bind a variable to configuration flag
158 * simgrid::config::bind_flag(a, "x", [](int x) { return x > 0; });
161 // F is a predicate, F : T const& -> bool
162 template <class T, class F>
163 typename std::enable_if<std::is_same<bool, decltype(std::declval<F>()(std::declval<const T&>()))>::value, void>::type
164 bind_flag(T& value, const char* name, const char* description, F callback)
166 declare_flag(name, description, value, std::function<void(const T&)>([&value, callback](const T& val) {
167 if (not callback(val))
168 throw std::range_error("invalid value.");
169 value = std::move(val);
173 /** A variable bound to a CLI option
176 * static simgrid::config::flag<int> answer("answer", "Expected answer", 42);
177 * static simgrid::config::flag<std::string> name("name", "Ford Perfect", "John Doe");
178 * static simgrid::config::flag<double> gamma("gamma", "Gamma factor", 1.987);
188 * @param name Flag name
189 * @param desc Flag description
190 * @param value Flag initial/default value
192 Flag(const char* name, const char* desc, T value) : value_(value)
194 simgrid::config::bind_flag(value_, name, desc);
197 /** Constructor taking also an array of aliases for name */
198 Flag(const char* name, std::initializer_list<const char*> aliases, const char* desc, T value) : value_(value)
200 simgrid::config::bind_flag(value_, name, std::move(aliases), desc);
203 /* A constructor accepting a callback that will be passed the parameter.
204 * It can either return a boolean (informing whether the parameter is valid), or returning void.
207 Flag(const char* name, const char* desc, T value, F callback) : value_(value)
209 simgrid::config::bind_flag(value_, name, desc, std::move(callback));
213 Flag(const char* name, std::initializer_list<const char*> aliases, const char* desc, T value, F callback)
216 simgrid::config::bind_flag(value_, name, std::move(aliases), desc, std::move(callback));
219 /* A constructor accepting a map of valid values -> their description,
220 * and producing an informative error message when an invalid value is passed, or when help is passed as a value.
223 Flag(const char* name, const char* desc, T value, std::map<T, std::string> valid_values, F callback) : value_(value)
225 simgrid::config::bind_flag(value_, name, desc, std::move(valid_values), std::move(callback));
229 Flag(Flag const&) = delete;
230 Flag& operator=(Flag const&) = delete;
232 // Get the underlying value:
233 T& get() { return value_; }
234 T const& get() const { return value_; }
236 // Implicit conversion to the underlying type:
237 operator T&() { return value_; }
238 operator T const&() const{ return value_; }
240 // Basic interop with T:
242 Flag& operator=(U const& that) { value_ = that; return *this; }
244 Flag& operator=(U && that) { value_ = that; return *this; }
246 bool operator==(U const& that) const { return value_ == that; }
248 bool operator!=(U const& that) const { return value_ != that; }
250 bool operator<(U const& that) const { return value_ < that; }
252 bool operator>(U const& that) const { return value_ > that; }
254 bool operator<=(U const& that) const { return value_ <= that; }
256 bool operator>=(U const& that) const { return value_ >= that; }
261 XBT_PUBLIC std::string xbt_cfg_get_string(const char* name);