git.sesse.net Git - casparcg/blob - common/scope_exit.h

   1 #pragma once
   2
   3 #include "except.h"
   4
   5 #include <functional>
   6
   7 namespace caspar {
   8
   9 namespace detail
  10 {
  11     template<typename T>
  12     class scope_exit
  13     {
  14                 scope_exit(const scope_exit&);
  15                 scope_exit& operator=(const scope_exit&);
  16     public:
  17
  18                 template<typename T2>
  19         explicit scope_exit(T2&& func)
  20                         : func_(std::forward<T2>(func))
  21                         , valid_(true)
  22                 {
  23                 }
  24
  25                 scope_exit(scope_exit&& other)
  26                         : func_(std::move(other.func_))
  27                         , valid_(std::move(other.valid_))
  28                 {
  29                         other.valid_ = false;
  30                 }
  31
  32                 scope_exit& operator=(scope_exit&& other)
  33                 {
  34                         func_  = std::move(other.func_);
  35                         valid_ = std::move(other.valid_);
  36
  37                         other.valid_ = false;
  38
  39                         return *this;
  40                 }
  41
  42         ~scope_exit()
  43                 {
  44                         try
  45                         {
  46                                 if(valid_)
  47                                         func_();
  48                         }
  49                         catch(...)
  50                         {
  51                                 if(!std::uncaught_exception())
  52 #pragma warning(push)
  53 #pragma warning(disable: 4297)
  54                                         throw;
  55 #pragma warning(pop)
  56                                 else
  57                                         CASPAR_LOG_CURRENT_EXCEPTION();
  58                         }
  59                 }
  60     private:
  61         T func_;
  62                 bool valid_;
  63     };
  64
  65         class scope_exit_helper {};
  66
  67         template <typename T>
  68         scope_exit<typename std::decay<T>::type> operator+(scope_exit_helper, T&& exitScope)
  69         {
  70                 return scope_exit<typename std::decay<T>::type>(std::forward<T>(exitScope));
  71         }
  72 }
  73
  74 #define _CASPAR_EXIT_SCOPE_LINENAME_CAT(name, line) name##line
  75 #define _CASPAR_EXIT_SCOPE_LINENAME(name, line) _CASPAR_EXIT_SCOPE_LINENAME_CAT(name, line)
  76 #define CASPAR_SCOPE_EXIT auto _CASPAR_EXIT_SCOPE_LINENAME(EXIT, __LINE__) = ::caspar::detail::scope_exit_helper() + [&]() mutable
  77
  78 }