vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/dll/shared_library.hpp

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// Copyright 2014 Renato Tegon Forti, Antony Polukhin.
// Copyright 2015-2016 Antony Polukhin.
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt
// or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_DLL_SHARED_LIBRARY_HPP
#define BOOST_DLL_SHARED_LIBRARY_HPP
/// \file boost/dll/shared_library.hpp
/// \brief Contains the boost::dll::shared_library class, core class for all the
/// DLL/DSO operations.
#include <boost/config.hpp>
#include <boost/predef/os.h>
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/is_member_pointer.hpp>
#include <boost/utility/explicit_operator_bool.hpp>
#include <boost/dll/detail/system_error.hpp>
#include <boost/dll/detail/aggressive_ptr_cast.hpp>
#if BOOST_OS_WINDOWS
# include <boost/dll/detail/windows/shared_library_impl.hpp>
#else
# include <boost/dll/detail/posix/shared_library_impl.hpp>
#endif
#ifdef BOOST_HAS_PRAGMA_ONCE
# pragma once
#endif
namespace boost { namespace dll {
/*!
* \brief This class can be used to load a
* Dynamic link libraries (DLL's) or Shared Libraries, also know
* as dynamic shared objects (DSO's) and get their exported
* symbols (functions and variables).
*
* shared_library instances share reference count to an actual loaded DLL/DSO, so it
* is safe and memory efficient to have multiple instances of shared_library referencing the same DLL/DSO
* even if those instances were loaded using different paths (relative + absolute) referencing the same object.
*
* On Linux/POSIX link with library "dl". "-fvisibility=hidden" flag is also recommended for use on Linux/POSIX.
*/
class shared_library
/// @cond
: private boost::dll::detail::shared_library_impl
/// @endcond
{
typedef boost::dll::detail::shared_library_impl base_t;
BOOST_COPYABLE_AND_MOVABLE(shared_library)
public:
#ifdef BOOST_DLL_DOXYGEN
typedef platform_specific native_handle_t;
#else
typedef shared_library_impl::native_handle_t native_handle_t;
#endif
/*!
* Creates in anstance that does not reference any DLL/DSO.
*
* \post this->is_loaded() returns false.
* \throw Nothing.
*/
shared_library() BOOST_NOEXCEPT {}
/*!
* Copy constructor that increments the reference count of an underlying shared library.
* Same as calling constructor with `lib.location()` parameter.
*
* \param lib A library to copy.
* \post lib == *this
* \throw boost::system::system_error, std::bad_alloc in case of insufficient memory.
*/
shared_library(const shared_library& lib)
: base_t()
{
assign(lib);
}
/*!
* Copy constructor that increments the reference count of an underlying shared library.
* Same as calling constructor with `lib.location(), ec` parameters.
*
* \param lib A shared library to copy.
* \param ec Variable that will be set to the result of the operation.
* \post lib == *this
* \throw std::bad_alloc in case of insufficient memory.
*/
shared_library(const shared_library& lib, boost::system::error_code& ec)
: base_t()
{
assign(lib, ec);
}
/*!
* Move constructor. Does not invalidate existing symbols and functions loaded from lib.
*
* \param lib A shared library to move from.
* \post lib.is_loaded() returns false, this->is_loaded() return true.
* \throw Nothing.
*/
shared_library(BOOST_RV_REF(shared_library) lib) BOOST_NOEXCEPT
: base_t(boost::move(static_cast<base_t&>(lib)))
{}
/*!
* Loads a library by specified path with a specified mode.
*
* \param lib_path Library file name. Can handle std::string, const char*, std::wstring,
* const wchar_t* or boost::filesystem::path.
* \param mode A mode that will be used on library load.
* \throw boost::system::system_error, std::bad_alloc in case of insufficient memory.
*/
explicit shared_library(const boost::filesystem::path& lib_path, load_mode::type mode = load_mode::default_mode) {
shared_library::load(lib_path, mode);
}
/*!
* Loads a library by specified path with a specified mode.
*
* \param lib_path Library file name. Can handle std::string, const char*, std::wstring,
* const wchar_t* or boost::filesystem::path.
* \param mode A mode that will be used on library load.
* \param ec Variable that will be set to the result of the operation.
* \throw std::bad_alloc in case of insufficient memory.
*/
shared_library(const boost::filesystem::path& lib_path, boost::system::error_code& ec, load_mode::type mode = load_mode::default_mode) {
shared_library::load(lib_path, mode, ec);
}
//! \overload shared_library(const boost::filesystem::path& lib_path, boost::system::error_code& ec, load_mode::type mode = load_mode::default_mode)
shared_library(const boost::filesystem::path& lib_path, load_mode::type mode, boost::system::error_code& ec) {
shared_library::load(lib_path, mode, ec);
}
/*!
* Assignment operator. If this->is_loaded() then calls this->unload(). Does not invalidate existing symbols and functions loaded from lib.
*
* \param lib A shared library to assign from.
* \post lib == *this
* \throw boost::system::system_error, std::bad_alloc in case of insufficient memory.
*/
shared_library& operator=(BOOST_COPY_ASSIGN_REF(shared_library) lib) {
boost::system::error_code ec;
assign(lib, ec);
if (ec) {
boost::dll::detail::report_error(ec, "boost::dll::shared_library::operator= failed");
}
return *this;
}
/*!
* Move assignment operator. If this->is_loaded() then calls this->unload(). Does not invalidate existing symbols and functions loaded from lib.
*
* \param lib A library to move from.
* \post lib.is_loaded() returns false.
* \throw Nothing.
*/
shared_library& operator=(BOOST_RV_REF(shared_library) lib) BOOST_NOEXCEPT {
if (lib.native() != native()) {
swap(lib);
}
return *this;
}
/*!
* Destroys the object by calling `unload()`. If library was loaded multiple times
* by different instances, the actual DLL/DSO won't be unloaded until
* there is at least one instance that references the DLL/DSO.
*
* \throw Nothing.
*/
~shared_library() BOOST_NOEXCEPT {}
/*!
* Makes *this share the same shared object as lib. If *this is loaded, then unloads it.
*
* \post lib.location() == this->location(), lib == *this
* \param lib A library to copy.
* \param ec Variable that will be set to the result of the operation.
* \throw std::bad_alloc in case of insufficient memory.
*/
shared_library& assign(const shared_library& lib, boost::system::error_code& ec) {
ec.clear();
if (native() == lib.native()) {
return *this;
}
if (!lib) {
unload();
return *this;
}
boost::filesystem::path loc = lib.location(ec);
if (ec) {
return *this;
}
shared_library copy(loc, ec);
if (ec) {
return *this;
}
swap(copy);
return *this;
}
/*!
* Makes *this share the same shared object as lib. If *this is loaded, then unloads it.
*
* \param lib A library instance to assign from.
* \post lib.location() == this->location()
* \throw boost::system::system_error, std::bad_alloc in case of insufficient memory.
*/
shared_library& assign(const shared_library& lib) {
boost::system::error_code ec;
assign(lib, ec);
if (ec) {
boost::dll::detail::report_error(ec, "boost::dll::shared_library::assign() failed");
}
return *this;
}
/*!
* Loads a library by specified path with a specified mode.
*
* Note that if some library is already loaded in this instance, load will
* call unload() and then load the new provided library.
*
* \param lib_path Library file name. Can handle std::string, const char*, std::wstring,
* const wchar_t* or boost::filesystem::path.
* \param mode A mode that will be used on library load.
* \throw boost::system::system_error, std::bad_alloc in case of insufficient memory.
*
*/
void load(const boost::filesystem::path& lib_path, load_mode::type mode = load_mode::default_mode) {
boost::system::error_code ec;
base_t::load(lib_path, mode, ec);
if (ec) {
boost::dll::detail::report_error(ec, "boost::dll::shared_library::load() failed");
}
}
/*!
* Loads a library by specified path with a specified mode.
*
* Note that if some library is already loaded in this instance, load will
* call unload() and then load the new provided library.
*
* \param lib_path Library file name. Can handle std::string, const char*, std::wstring,
* const wchar_t* or boost::filesystem::path.
* \param ec Variable that will be set to the result of the operation.
* \param mode A mode that will be used on library load.
* \throw std::bad_alloc in case of insufficient memory.
*/
void load(const boost::filesystem::path& lib_path, boost::system::error_code& ec, load_mode::type mode = load_mode::default_mode) {
ec.clear();
base_t::load(lib_path, mode, ec);
}
//! \overload void load(const boost::filesystem::path& lib_path, boost::system::error_code& ec, load_mode::type mode = load_mode::default_mode)
void load(const boost::filesystem::path& lib_path, load_mode::type mode, boost::system::error_code& ec) {
ec.clear();
base_t::load(lib_path, mode, ec);
}
/*!
* Unloads a shared library. If library was loaded multiple times
* by different instances, the actual DLL/DSO won't be unloaded until
* there is at least one instance that references the DLL/DSO.
*
* \post this->is_loaded() returns false.
* \throw Nothing.
*/
void unload() BOOST_NOEXCEPT {
base_t::unload();
}
/*!
* Check if an library is loaded.
*
* \return true if a library has been loaded.
* \throw Nothing.
*/
bool is_loaded() const BOOST_NOEXCEPT {
return base_t::is_loaded();
}
/*!
* Check if an library is not loaded.
*
* \return true if a library has not been loaded.
* \throw Nothing.
*/
bool operator!() const BOOST_NOEXCEPT {
return !is_loaded();
}
/*!
* Check if an library is loaded.
*
* \return true if a library has been loaded.
* \throw Nothing.
*/
BOOST_EXPLICIT_OPERATOR_BOOL()
/*!
* Search for a given symbol on loaded library. Works for all symbols, including alias names.
*
* \param symbol_name Null-terminated symbol name. Can handle std::string, char*, const char*.
* \return `true` if the loaded library contains a symbol with a given name.
* \throw Nothing.
*/
bool has(const char* symbol_name) const BOOST_NOEXCEPT {
boost::system::error_code ec;
return is_loaded() && !!base_t::symbol_addr(symbol_name, ec) && !ec;
}
//! \overload bool has(const char* symbol_name) const
bool has(const std::string& symbol_name) const BOOST_NOEXCEPT {
return has(symbol_name.c_str());
}
/*!
* Returns reference to the symbol (function or variable) with the given name from the loaded library.
* This call will always succeed and throw nothing if call to `has(const char* )`
* member function with the same symbol name returned `true`.
*
* \b Example:
* \code
* int& i0 = lib.get<int>("integer_name");
* int& i1 = *lib.get<int*>("integer_alias_name");
* \endcode
*
* \tparam T Type of the symbol that we are going to import. Must be explicitly specified.
* \param symbol_name Null-terminated symbol name. Can handle std::string, char*, const char*.
* \return Reference to the symbol.
* \throw boost::system::system_error if symbol does not exist or if the DLL/DSO was not loaded.
*/
template <typename T>
inline typename boost::enable_if_c<boost::is_member_pointer<T>::value || boost::is_reference<T>::value, T>::type get(const std::string& symbol_name) const {
return get<T>(symbol_name.c_str());
}
//! \overload T& get(const std::string& symbol_name) const
template <typename T>
inline typename boost::disable_if_c<boost::is_member_pointer<T>::value || boost::is_reference<T>::value, T&>::type get(const std::string& symbol_name) const {
return get<T>(symbol_name.c_str());
}
//! \overload T& get(const std::string& symbol_name) const
template <typename T>
inline typename boost::enable_if_c<boost::is_member_pointer<T>::value || boost::is_reference<T>::value, T>::type get(const char* symbol_name) const {
return boost::dll::detail::aggressive_ptr_cast<T>(
get_void(symbol_name)
);
}
//! \overload T& get(const std::string& symbol_name) const
template <typename T>
inline typename boost::disable_if_c<boost::is_member_pointer<T>::value || boost::is_reference<T>::value, T&>::type get(const char* symbol_name) const {
return *boost::dll::detail::aggressive_ptr_cast<T*>(
get_void(symbol_name)
);
}
/*!
* Returns a symbol (function or variable) from a shared library by alias name of the symbol.
*
* \b Example:
* \code
* int& i = lib.get_alias<int>("integer_alias_name");
* \endcode
*
* \tparam T Type of the symbol that we are going to import. Must be explicitly specified..
* \param alias_name Null-terminated alias symbol name. Can handle std::string, char*, const char*.
* \throw boost::system::system_error if symbol does not exist or if the DLL/DSO was not loaded.
*/
template <typename T>
inline T& get_alias(const char* alias_name) const {
return *get<T*>(alias_name);
}
//! \overload T& get_alias(const char* alias_name) const
template <typename T>
inline T& get_alias(const std::string& alias_name) const {
return *get<T*>(alias_name.c_str());
}
private:
/// @cond
// get_void is required to reduce binary size: it does not depend on a template
// parameter and will be instantiated only once.
void* get_void(const char* sb) const {
boost::system::error_code ec;
if (!is_loaded()) {
ec = boost::system::error_code(
boost::system::errc::bad_file_descriptor,
boost::system::generic_category()
);
// report_error() calls dlsym, do not use it here!
boost::throw_exception(
boost::system::system_error(
ec, "boost::dll::shared_library::get() failed: no library was loaded"
)
);
}
void* const ret = base_t::symbol_addr(sb, ec);
if (ec || !ret) {
boost::dll::detail::report_error(ec, "boost::dll::shared_library::get() failed");
}
return ret;
}
/// @endcond
public:
/*!
* Returns the native handler of the loaded library.
*
* \return Platform-specific handle.
*/
native_handle_t native() const BOOST_NOEXCEPT {
return base_t::native();
}
/*!
* Returns full path and name of this shared object.
*
* \b Example:
* \code
* shared_library lib("test_lib.dll");
* filesystem::path full_path = lib.location(); // C:\Windows\System32\test_lib.dll
* \endcode
*
* \return Full path to the shared library.
* \throw boost::system::system_error, std::bad_alloc.
*/
boost::filesystem::path location() const {
boost::system::error_code ec;
if (!is_loaded()) {
ec = boost::system::error_code(
boost::system::errc::bad_file_descriptor,
boost::system::generic_category()
);
boost::throw_exception(
boost::system::system_error(
ec, "boost::dll::shared_library::location() failed (no library was loaded)"
)
);
}
boost::filesystem::path full_path = base_t::full_module_path(ec);
if (ec) {
boost::dll::detail::report_error(ec, "boost::dll::shared_library::location() failed");
}
return full_path;
}
/*!
* Returns full path and name of shared module.
*
* \b Example:
* \code
* shared_library lib("test_lib.dll");
* filesystem::path full_path = lib.location(); // C:\Windows\System32\test_lib.dll
* \endcode
*
* \param ec Variable that will be set to the result of the operation.
* \return Full path to the shared library.
* \throw std::bad_alloc.
*/
boost::filesystem::path location(boost::system::error_code& ec) const {
if (!is_loaded()) {
ec = boost::system::error_code(
boost::system::errc::bad_file_descriptor,
boost::system::generic_category()
);
return boost::filesystem::path();
}
ec.clear();
return base_t::full_module_path(ec);
}
/*!
* Returns suffix of shared module:
* in a call to load() or the constructor/load.
*
* \return The suffix od shared module: ".dll" (Windows), ".so" (Unix/Linux/BSD), ".dylib" (MacOS/IOS)
*/
static boost::filesystem::path suffix() {
return base_t::suffix();
}
/*!
* Swaps two libraries. Does not invalidate existing symbols and functions loaded from libraries.
*
* \param rhs Library to swap with.
* \throw Nothing.
*/
void swap(shared_library& rhs) BOOST_NOEXCEPT {
base_t::swap(rhs);
}
};
/// Very fast equality check that compares the actual DLL/DSO objects. Throws nothing.
inline bool operator==(const shared_library& lhs, const shared_library& rhs) BOOST_NOEXCEPT {
return lhs.native() == rhs.native();
}
/// Very fast inequality check that compares the actual DLL/DSO objects. Throws nothing.
inline bool operator!=(const shared_library& lhs, const shared_library& rhs) BOOST_NOEXCEPT {
return lhs.native() != rhs.native();
}
/// Compare the actual DLL/DSO objects without any guarantee to be stable between runs. Throws nothing.
inline bool operator<(const shared_library& lhs, const shared_library& rhs) BOOST_NOEXCEPT {
return lhs.native() < rhs.native();
}
/// Swaps two shared libraries. Does not invalidate symbols and functions loaded from libraries. Throws nothing.
inline void swap(shared_library& lhs, shared_library& rhs) BOOST_NOEXCEPT {
lhs.swap(rhs);
}
}} // boost::dll
#endif // BOOST_DLL_SHARED_LIBRARY_HPP