Add wrapper for getting X509_digest from a cert

[folly.git] / folly / Function.h

diff --git a/folly/Function.h b/folly/Function.h
index a73a8b7a4484203bf4927634b3d01edc9427ddb6..ec145688b75ca0316e184db6c915277acbcc386b 100644 (file)
--- a/folly/Function.h
+++ b/folly/Function.h
@@ -226,6 +226,7 @@
 #include <folly/CppAttributes.h>
 #include <folly/Portability.h>
 #include <folly/Traits.h>
+#include <folly/functional/Invoke.h>
 
 namespace folly {
 
@@ -236,6 +237,12 @@ template <typename ReturnType, typename... Args>
 Function<ReturnType(Args...) const> constCastFunction(
     Function<ReturnType(Args...)>&&) noexcept;
 
+#if FOLLY_HAVE_NOEXCEPT_FUNCTION_TYPE
+template <typename ReturnType, typename... Args>
+Function<ReturnType(Args...) const noexcept> constCastFunction(
+    Function<ReturnType(Args...) noexcept>&&) noexcept;
+#endif
+
 namespace detail {
 namespace function {
 
@@ -370,6 +377,98 @@ struct FunctionTraits<ReturnType(Args...) const> {
   };
 };
 
+#if FOLLY_HAVE_NOEXCEPT_FUNCTION_TYPE
+template <typename ReturnType, typename... Args>
+struct FunctionTraits<ReturnType(Args...) noexcept> {
+  using Call = ReturnType (*)(Data&, Args&&...) noexcept;
+  using IsConst = std::false_type;
+  using ConstSignature = ReturnType(Args...) const noexcept;
+  using NonConstSignature = ReturnType(Args...) noexcept;
+  using OtherSignature = ConstSignature;
+
+  template <typename F, typename G = typename std::decay<F>::type>
+  using ResultOf = decltype(
+      static_cast<ReturnType>(std::declval<G&>()(std::declval<Args>()...)));
+
+  template <typename Fun>
+  static ReturnType callSmall(Data& p, Args&&... args) noexcept {
+    return static_cast<ReturnType>((*static_cast<Fun*>(
+        static_cast<void*>(&p.tiny)))(static_cast<Args&&>(args)...));
+  }
+
+  template <typename Fun>
+  static ReturnType callBig(Data& p, Args&&... args) noexcept {
+    return static_cast<ReturnType>(
+        (*static_cast<Fun*>(p.big))(static_cast<Args&&>(args)...));
+  }
+
+  static ReturnType uninitCall(Data&, Args&&...) noexcept {
+    throw std::bad_function_call();
+  }
+
+  ReturnType operator()(Args... args) noexcept {
+    auto& fn = *static_cast<Function<NonConstSignature>*>(this);
+    return fn.call_(fn.data_, static_cast<Args&&>(args)...);
+  }
+
+  class SharedProxy {
+    std::shared_ptr<Function<NonConstSignature>> sp_;
+
+   public:
+    explicit SharedProxy(Function<NonConstSignature>&& func)
+        : sp_(std::make_shared<Function<NonConstSignature>>(std::move(func))) {}
+    ReturnType operator()(Args&&... args) const {
+      return (*sp_)(static_cast<Args&&>(args)...);
+    }
+  };
+};
+
+template <typename ReturnType, typename... Args>
+struct FunctionTraits<ReturnType(Args...) const noexcept> {
+  using Call = ReturnType (*)(Data&, Args&&...) noexcept;
+  using IsConst = std::true_type;
+  using ConstSignature = ReturnType(Args...) const noexcept;
+  using NonConstSignature = ReturnType(Args...) noexcept;
+  using OtherSignature = NonConstSignature;
+
+  template <typename F, typename G = typename std::decay<F>::type>
+  using ResultOf = decltype(static_cast<ReturnType>(
+      std::declval<const G&>()(std::declval<Args>()...)));
+
+  template <typename Fun>
+  static ReturnType callSmall(Data& p, Args&&... args) noexcept {
+    return static_cast<ReturnType>((*static_cast<const Fun*>(
+        static_cast<void*>(&p.tiny)))(static_cast<Args&&>(args)...));
+  }
+
+  template <typename Fun>
+  static ReturnType callBig(Data& p, Args&&... args) noexcept {
+    return static_cast<ReturnType>(
+        (*static_cast<const Fun*>(p.big))(static_cast<Args&&>(args)...));
+  }
+
+  static ReturnType uninitCall(Data&, Args&&...) noexcept {
+    throw std::bad_function_call();
+  }
+
+  ReturnType operator()(Args... args) const noexcept {
+    auto& fn = *static_cast<const Function<ConstSignature>*>(this);
+    return fn.call_(fn.data_, static_cast<Args&&>(args)...);
+  }
+
+  class SharedProxy {
+    std::shared_ptr<Function<ConstSignature>> sp_;
+
+   public:
+    explicit SharedProxy(Function<ConstSignature>&& func)
+        : sp_(std::make_shared<Function<ConstSignature>>(std::move(func))) {}
+    ReturnType operator()(Args&&... args) const {
+      return (*sp_)(static_cast<Args&&>(args)...);
+    }
+  };
+};
+#endif
+
 template <typename Fun>
 bool execSmall(Op o, Data* src, Data* dst) {
   switch (o) {
@@ -405,19 +504,6 @@ bool execBig(Op o, Data* src, Data* dst) {
   return true;
 }
 
-// Invoke helper
-template <typename F, typename... Args>
-inline constexpr auto invoke(F&& f, Args&&... args)
-    -> decltype(std::forward<F>(f)(std::forward<Args>(args)...)) {
-  return std::forward<F>(f)(std::forward<Args>(args)...);
-}
-
-template <typename M, typename C, typename... Args>
-inline constexpr auto invoke(M(C::*d), Args&&... args)
-    -> decltype(std::mem_fn(d)(std::forward<Args>(args)...)) {
-  return std::mem_fn(d)(std::forward<Args>(args)...);
-}
-
 } // namespace function
 } // namespace detail
 
@@ -443,7 +529,7 @@ class Function final : private detail::function::FunctionTraits<FunctionType> {
   // invoking undefined behavior. Const-correctness is only violated when
   // `FunctionType` is a const function type (e.g., `int() const`) and `*this`
   // is the result of calling `constCastFunction`.
-  mutable Data data_;
+  mutable Data data_{};
   Call call_{&Traits::uninitCall};
   Exec exec_{&detail::function::uninitNoop};
 
@@ -492,9 +578,11 @@ class Function final : private detail::function::FunctionTraits<FunctionType> {
   Function(const Function&) = delete;
 
 #if __OBJC__
-  // Delete conversion from Objective-C blocks
+  // Make sure Objective C blocks are copied
   template <class ReturnType, class... Args>
-  Function(ReturnType (^)(Args...)) = delete;
+  /*implicit*/ Function(ReturnType (^objCBlock)(Args... args))
+      : Function([blockCopy = (ReturnType (^)(Args...))[objCBlock copy]](
+                     Args... args) { return blockCopy(args...); }){};
 #endif
 
   /**
@@ -577,9 +665,13 @@ class Function final : private detail::function::FunctionTraits<FunctionType> {
   Function& operator=(const Function&) = delete;
 
 #if __OBJC__
-  // Delete conversion from Objective-C blocks
+  // Make sure Objective C blocks are copied
   template <class ReturnType, class... Args>
-  Function& operator=(ReturnType (^)(Args...)) = delete;
+  /* implicit */ Function &operator=(ReturnType (^objCBlock)(Args... args)) {
+    (*this) = [blockCopy = (ReturnType (^)(Args...))[objCBlock copy]](
+                  Args... args) { return blockCopy(args...); };
+    return *this;
+  }
 #endif
 
   /**
@@ -749,6 +841,21 @@ Function<ReturnType(Args...) const> constCastFunction(
   return std::move(that);
 }
 
+#if FOLLY_HAVE_NOEXCEPT_FUNCTION_TYPE
+template <typename ReturnType, typename... Args>
+Function<ReturnType(Args...) const noexcept> constCastFunction(
+    Function<ReturnType(Args...) noexcept>&& that) noexcept {
+  return Function<ReturnType(Args...) const noexcept>{
+      std::move(that), detail::function::CoerceTag{}};
+}
+
+template <typename ReturnType, typename... Args>
+Function<ReturnType(Args...) const noexcept> constCastFunction(
+    Function<ReturnType(Args...) const noexcept>&& that) noexcept {
+  return std::move(that);
+}
+#endif
+
 namespace detail {
 namespace function {
 template <typename Fun, typename FunctionType, typename = void>
@@ -765,8 +872,8 @@ struct IsCallableAsImpl<
 
 template <typename Fun, typename FunctionType>
 struct IsCallableAs : IsCallableAsImpl<Fun, FunctionType> {};
-}
-}
+} // namespace function
+} // namespace detail
 
 /**
  * @class FunctionRef
@@ -802,7 +909,7 @@ class FunctionRef<ReturnType(Args...)> final {
   template <typename Fun>
   static ReturnType call(void* object, Args&&... args) {
     using Pointer = _t<std::add_pointer<Fun>>;
-    return static_cast<ReturnType>(detail::function::invoke(
+    return static_cast<ReturnType>(invoke(
         static_cast<Fun&&>(*static_cast<Pointer>(object)),
         static_cast<Args&&>(args)...));
   }