Add nameof & scope_exit

include/libipc/imp/nameof.h

@@ -0,0 +1,43 @@
+/**
+ * \file libimp/nameof.h
+ * \author mutouyun (orz@orzz.org)
+ * \brief Gets the name string of a type.
+ */
+#pragma once
+
+#include <typeinfo>
+#include <string>
+#include <cstring>
+
+#include "libipc/imp/export.h"
+#include "libipc/imp/span.h"
+#include "libipc/imp/detect_plat.h"
+
+namespace ipc {
+
+/**
+ * \brief The conventional way to obtain demangled symbol name.
+ * \see https://www.boost.org/doc/libs/1_80_0/libs/core/doc/html/core/demangle.html
+ * 
+ * \param name the mangled name
+ * \return std::string a human-readable demangled type name
+ */
+IPC_EXPORT std::string demangle(std::string name) noexcept;
+
+/**
+ * \brief Returns an implementation defined string containing the name of the type.
+ * \see https://en.cppreference.com/w/cpp/types/type_info/name
+ * 
+ * \tparam T a type
+ * \return std::string a human-readable demangled type name
+ */
+template <typename T>
+std::string nameof() noexcept {
+  LIBIPC_TRY {
+    return demangle(typeid(T).name());
+  } LIBIPC_CATCH(...) {
+    return {};
+  }
+}
+
+} // namespace ipc

include/libipc/imp/scope_exit.h

@@ -0,0 +1,77 @@
+/**
+ * \file libimp/scope_exit.h
+ * \author mutouyun (orz@orzz.org)
+ * \brief Execute guard function when the enclosing scope exits.
+ */
+#pragma once
+
+#include <utility>      // std::forward, std::move
+#include <functional>   // std::function
+#include <type_traits>
+
+#include "libipc/imp/detect_plat.h"
+
+namespace ipc {
+
+template <typename F = std::function<void()>>
+class scope_exit {
+  F destructor_;
+  mutable bool released_;
+
+public:
+  template <typename G>
+  explicit scope_exit(G &&destructor) noexcept
+    : destructor_(std::forward<G>(destructor))
+    , released_  (false) {}
+
+  scope_exit(scope_exit &&other) noexcept
+    : destructor_(std::move(other.destructor_))
+    , released_  (std::exchange(other.released_, true)) /*release rhs*/ {}
+
+  scope_exit &operator=(scope_exit &&other) noexcept {
+    destructor_ = std::move(other.destructor_);
+    released_   = std::exchange(other.released_, true);
+    return *this;
+  }
+
+  ~scope_exit() noexcept {
+    if (!released_) destructor_();
+  }
+
+  void release() const noexcept {
+    released_ = true;
+  }
+
+  void do_exit() noexcept {
+    if (released_) return;
+    destructor_();
+    released_ = true;
+  }
+
+  void swap(scope_exit &other) noexcept {
+    std::swap(destructor_, other.destructor_);
+    std::swap(released_  , other.released_);
+  }
+};
+
+/// \brief Creates a scope_exit object.
+template <typename F>
+auto make_scope_exit(F &&destructor) noexcept {
+  return scope_exit<std::decay_t<F>>(std::forward<F>(destructor));
+}
+
+namespace detail_scope_exit {
+
+struct scope_exit_helper {
+  template <typename F>
+  auto operator=(F &&f) const noexcept {
+    return make_scope_exit(std::forward<F>(f));
+  }
+};
+
+} // namespace detail_scope_exit
+
+#define LIBIPC_SCOPE_EXIT($VAL) \
+  LIBIPC_UNUSED auto $VAL = ::ipc::detail_scope_exit::scope_exit_helper{}
+
+} // namespace ipc

src/CMakeLists.txt

@@ -5,6 +5,8 @@ set (PACKAGE_VERSION 1.3.0)
 aux_source_directory(${LIBIPC_PROJECT_DIR}/src/libipc SRC_FILES)
 aux_source_directory(${LIBIPC_PROJECT_DIR}/src/libipc/sync SRC_FILES)
 aux_source_directory(${LIBIPC_PROJECT_DIR}/src/libipc/platform SRC_FILES)
+aux_source_directory(${LIBIPC_PROJECT_DIR}/src/libipc/imp SRC_FILES)
+aux_source_directory(${LIBIPC_PROJECT_DIR}/src/libipc/mem SRC_FILES)
 
 file(GLOB HEAD_FILES
   ${LIBIPC_PROJECT_DIR}/include/libipc/*.h

src/libipc/imp/nameof.cpp

@@ -0,0 +1,7 @@
+
+#include "libipc/imp/detect_plat.h"
+#if defined(LIBIPC_CC_GNUC)
+# include "libipc/platform/gnuc/demangle.h"
+#else
+# include "libipc/platform/win/demangle.h"
+#endif

src/libipc/platform/gnuc/demangle.h

@@ -0,0 +1,43 @@
+/**
+ * \file libipc/platform/gnuc/demangle.h
+ * \author mutouyun (orz@orzz.org)
+ */
+#pragma once
+
+#include <cxxabi.h> // abi::__cxa_demangle
+#include <cstdlib>  // std::malloc
+
+#include "libipc/imp/nameof.h"
+#include "libipc/imp/scope_exit.h"
+#include "libipc/imp/detect_plat.h"
+
+namespace ipc {
+
+/**
+ * \brief The conventional way to obtain demangled symbol name.
+ * \see https://www.boost.org/doc/libs/1_80_0/libs/core/doc/html/core/demangle.html
+ * 
+ * \param name the mangled name
+ * \return std::string a human-readable demangled type name
+ */
+std::string demangle(std::string name) noexcept {
+  /// \see https://gcc.gnu.org/onlinedocs/libstdc++/libstdc++-html-USERS-4.3/a01696.html
+  std::size_t sz = name.size() + 1;
+  char *buffer = static_cast<char *>(std::malloc(sz));
+  int status = 0;
+  char *realname = abi::__cxa_demangle(name.data(), buffer, &sz, &status);
+  if (realname == nullptr) {
+    std::free(buffer);
+    return {};
+  }
+  LIBIPC_SCOPE_EXIT(guard) = [realname] {
+    std::free(realname);
+  };
+  LIBIPC_TRY {
+    return std::move(name.assign(realname, sz));
+  } LIBIPC_CATCH(...) {
+    return {};
+  }
+}
+
+} // namespace ipc

src/libipc/platform/win/demangle.h

@@ -0,0 +1,15 @@
+/**
+ * \file libipc/platform/win/demangle.h
+ * \author mutouyun (orz@orzz.org)
+ */
+#pragma once
+
+#include "libipc/imp/nameof.h"
+
+namespace ipc {
+
+std::string demangle(std::string name) noexcept {
+  return std::move(name);
+}
+
+} // namespace ipc