ceph/src/boost/boost/outcome/iostream_support.hpp

   1 /* iostream specialisations for result and outcome
   2 (C) 2017-2019 Niall Douglas <http://www.nedproductions.biz/> (21 commits)
   3 File Created: July 2017
   4
   5
   6 Boost Software License - Version 1.0 - August 17th, 2003
   7
   8 Permission is hereby granted, free of charge, to any person or organization
   9 obtaining a copy of the software and accompanying documentation covered by
  10 this license (the "Software") to use, reproduce, display, distribute,
  11 execute, and transmit the Software, and to prepare derivative works of the
  12 Software, and to permit third-parties to whom the Software is furnished to
  13 do so, all subject to the following:
  14
  15 The copyright notices in the Software and this entire statement, including
  16 the above license grant, this restriction and the following disclaimer,
  17 must be included in all copies of the Software, in whole or in part, and
  18 all derivative works of the Software, unless such copies or derivative
  19 works are solely in the form of machine-executable object code generated by
  20 a source language processor.
  21
  22 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24 FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
  25 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
  26 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
  27 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  28 DEALINGS IN THE SOFTWARE.
  29 */
  30
  31 #ifndef BOOST_OUTCOME_IOSTREAM_SUPPORT_HPP
  32 #define BOOST_OUTCOME_IOSTREAM_SUPPORT_HPP
  33
  34 #include "outcome.hpp"
  35
  36 #include <iostream>
  37 #include <sstream>
  38
  39 BOOST_OUTCOME_V2_NAMESPACE_BEGIN
  40
  41 namespace detail
  42 {
  43   template <class T> typename std::add_lvalue_reference<T>::type lvalueref() noexcept;
  44
  45   template <class T> inline std::ostream &operator<<(std::ostream &s, const value_storage_trivial<T> &v)
  46   {
  47     s << v._status << " ";
  48     if((v._status & status_have_value) != 0)
  49     {
  50       s << v._value;  // NOLINT
  51     }
  52     return s;
  53   }
  54   inline std::ostream &operator<<(std::ostream &s, const value_storage_trivial<void> &v)
  55   {
  56     s << v._status << " ";
  57     return s;
  58   }
  59   template <class T> inline std::ostream &operator<<(std::ostream &s, const value_storage_nontrivial<T> &v)
  60   {
  61     s << v._status << " ";
  62     if((v._status & status_have_value) != 0)
  63     {
  64       s << v._value;  // NOLINT
  65     }
  66     return s;
  67   }
  68   template <class T> inline std::istream &operator>>(std::istream &s, value_storage_trivial<T> &v)
  69   {
  70     v = value_storage_trivial<T>();
  71     s >> v._status;
  72     if((v._status & status_have_value) != 0)
  73     {
  74       new(&v._value) decltype(v._value)();  // NOLINT
  75       s >> v._value;                        // NOLINT
  76     }
  77     return s;
  78   }
  79   inline std::istream &operator>>(std::istream &s, value_storage_trivial<devoid<void>> &v)
  80   {
  81     v = value_storage_trivial<devoid<void>>();
  82     s >> v._status;
  83     return s;
  84   }
  85   template <class T> inline std::istream &operator>>(std::istream &s, value_storage_nontrivial<T> &v)
  86   {
  87     v = value_storage_nontrivial<T>();
  88     s >> v._status;
  89     if((v._status & status_have_value) != 0)
  90     {
  91       new(&v._value) decltype(v._value)();  // NOLINT
  92       s >> v._value;                        // NOLINT
  93     }
  94     return s;
  95   }
  96   BOOST_OUTCOME_TEMPLATE(class T)
  97   BOOST_OUTCOME_TREQUIRES(BOOST_OUTCOME_TPRED(!std::is_constructible<std::error_code, T>::value))
  98   inline std::string safe_message(T && /*unused*/) { return {}; }
  99   inline std::string safe_message(const std::error_code &ec) { return " (" + ec.message() + ")"; }
 100 }  // namespace detail
 101
 102 /*! AWAITING HUGO JSON CONVERSION TOOL
 103 SIGNATURE NOT RECOGNISED
 104 */
 105 BOOST_OUTCOME_TEMPLATE(class R, class S, class P)
 106 BOOST_OUTCOME_TREQUIRES(BOOST_OUTCOME_TEXPR(detail::lvalueref<std::istream>() >> detail::lvalueref<R>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::istream>() >> detail::lvalueref<S>()))
 107 inline std::istream &operator>>(std::istream &s, basic_result<R, S, P> &v)
 108 {
 109   s >> v._iostreams_state();
 110   if(v.has_error())
 111   {
 112     s >> v.assume_error();
 113   }
 114   return s;
 115 }
 116 /*! AWAITING HUGO JSON CONVERSION TOOL
 117 SIGNATURE NOT RECOGNISED
 118 */
 119 BOOST_OUTCOME_TEMPLATE(class R, class S, class P)
 120 BOOST_OUTCOME_TREQUIRES(BOOST_OUTCOME_TEXPR(detail::lvalueref<std::ostream>() << detail::lvalueref<R>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::ostream>() << detail::lvalueref<S>()))
 121 inline std::ostream &operator<<(std::ostream &s, const basic_result<R, S, P> &v)
 122 {
 123   s << v._iostreams_state();
 124   if(v.has_error())
 125   {
 126     s << v.assume_error();
 127   }
 128   return s;
 129 }
 130 /*! AWAITING HUGO JSON CONVERSION TOOL
 131 SIGNATURE NOT RECOGNISED
 132 */
 133 template <class R, class S, class P> inline std::string print(const basic_result<R, S, P> &v)
 134 {
 135   std::stringstream s;
 136   if(v.has_value())
 137   {
 138     s << v.value();
 139   }
 140   if(v.has_error())
 141   {
 142     s << v.error() << detail::safe_message(v.error());
 143   }
 144   return s.str();
 145 }
 146 /*! AWAITING HUGO JSON CONVERSION TOOL
 147 SIGNATURE NOT RECOGNISED
 148 */
 149 template <class S, class P> inline std::string print(const basic_result<void, S, P> &v)
 150 {
 151   std::stringstream s;
 152   if(v.has_value())
 153   {
 154     s << "(+void)";
 155   }
 156   if(v.has_error())
 157   {
 158     s << v.error() << detail::safe_message(v.error());
 159   }
 160   return s.str();
 161 }
 162 /*! AWAITING HUGO JSON CONVERSION TOOL
 163 SIGNATURE NOT RECOGNISED
 164 */
 165 template <class R, class P> inline std::string print(const basic_result<R, void, P> &v)
 166 {
 167   std::stringstream s;
 168   if(v.has_value())
 169   {
 170     s << v.value();
 171   }
 172   if(v.has_error())
 173   {
 174     s << "(-void)";
 175   }
 176   return s.str();
 177 }
 178 /*! AWAITING HUGO JSON CONVERSION TOOL
 179 SIGNATURE NOT RECOGNISED
 180 */
 181 template <class P> inline std::string print(const basic_result<void, void, P> &v)
 182 {
 183   std::stringstream s;
 184   if(v.has_value())
 185   {
 186     s << "(+void)";
 187   }
 188   if(v.has_error())
 189   {
 190     s << "(-void)";
 191   }
 192   return s.str();
 193 }
 194
 195 /*! AWAITING HUGO JSON CONVERSION TOOL
 196 SIGNATURE NOT RECOGNISED
 197 */
 198 BOOST_OUTCOME_TEMPLATE(class R, class S, class P, class N)
 199 BOOST_OUTCOME_TREQUIRES(BOOST_OUTCOME_TEXPR(detail::lvalueref<std::istream>() >> detail::lvalueref<R>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::istream>() >> detail::lvalueref<S>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::istream>() >> detail::lvalueref<P>()))
 200 inline std::istream &operator>>(std::istream &s, outcome<R, S, P, N> &v)
 201 {
 202   s >> v._iostreams_state();
 203   if(v.has_error())
 204   {
 205     s >> v.assume_error();
 206   }
 207   if(v.has_exception())
 208   {
 209     s >> v.assume_exception();
 210   }
 211   return s;
 212 }
 213 /*! AWAITING HUGO JSON CONVERSION TOOL
 214 SIGNATURE NOT RECOGNISED
 215 */
 216 BOOST_OUTCOME_TEMPLATE(class R, class S, class P, class N)
 217 BOOST_OUTCOME_TREQUIRES(BOOST_OUTCOME_TEXPR(detail::lvalueref<std::ostream>() << detail::lvalueref<R>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::ostream>() << detail::lvalueref<S>()), BOOST_OUTCOME_TEXPR(detail::lvalueref<std::ostream>() << detail::lvalueref<P>()))
 218 inline std::ostream &operator<<(std::ostream &s, const outcome<R, S, P, N> &v)
 219 {
 220   s << v._iostreams_state();
 221   if(v.has_error())
 222   {
 223     s << v.assume_error();
 224   }
 225   if(v.has_exception())
 226   {
 227     s << v.assume_exception();
 228   }
 229   return s;
 230 }
 231 /*! AWAITING HUGO JSON CONVERSION TOOL
 232 SIGNATURE NOT RECOGNISED
 233 */
 234 template <class R, class S, class P, class N> inline std::string print(const outcome<R, S, P, N> &v)
 235 {
 236   std::stringstream s;
 237   int total = static_cast<int>(v.has_value()) + static_cast<int>(v.has_error()) + static_cast<int>(v.has_exception());
 238   if(total > 1)
 239   {
 240     s << "{ ";
 241   }
 242   s << print(static_cast<const basic_result<R, S, N> &>(static_cast<const detail::basic_result_final<R, S, N> &>(v)));  // NOLINT
 243   if(total > 1)
 244   {
 245     s << ", ";
 246   }
 247   if(v.has_exception())
 248   {
 249 #ifndef BOOST_NO_EXCEPTIONS
 250     try
 251     {
 252       rethrow_exception(v.exception());
 253     }
 254     catch(const std::system_error &e)
 255     {
 256       s << "std::system_error code " << e.code() << ": " << e.what();
 257     }
 258     catch(const std::exception &e)
 259     {
 260       s << "std::exception: " << e.what();
 261     }
 262     catch(...)
 263 #endif
 264     {
 265       s << "unknown exception";
 266     }
 267   }
 268   if(total > 1)
 269   {
 270     s << " }";
 271   }
 272   return s.str();
 273 }
 274 BOOST_OUTCOME_V2_NAMESPACE_END
 275
 276 #endif