101 lines
1.9 KiB
C++
101 lines
1.9 KiB
C++
|
#ifndef HOOK_HPP_RNAM6XF4
|
||
|
|
#define HOOK_HPP_RNAM6XF4
|
||
|
|
|
||
|
|
#include <functional>
|
||
|
|
#include <utility>
|
||
|
|
|
||
|
|
namespace vanetza
|
||
|
|
{
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Hook mechanism for realising extension points
|
||
|
|
*/
|
||
|
|
template<typename... Args>
|
||
|
|
class Hook
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
typedef std::function<void(Args...)> callback_type;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Assign a callback to hook, replaces previously assigned one
|
||
|
|
* \param cb A callable used as hook callback, e.g. lambda
|
||
|
|
*/
|
||
|
|
void operator=(callback_type&& cb)
|
||
|
|
{
|
||
|
|
m_function = std::move(cb);
|
||
|
|
}
|
||
|
|
|
||
|
|
void operator=(const callback_type& cb)
|
||
|
|
{
|
||
|
|
m_function = cb;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Execute hook callback if assigned
|
||
|
|
* \param Args... various arguments passed to assigned callback
|
||
|
|
*/
|
||
|
|
void operator()(Args... args)
|
||
|
|
{
|
||
|
|
if (m_function) {
|
||
|
|
// that's an arcane syntax, isn't it?
|
||
|
|
m_function(std::forward<Args>(args)...);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Reset previously assigned callback.
|
||
|
|
* No callback will be invoked when triggering hook after reset.
|
||
|
|
*/
|
||
|
|
void reset()
|
||
|
|
{
|
||
|
|
m_function = nullptr;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \deprecated previous name of reset
|
||
|
|
*/
|
||
|
|
void clear() { reset(); }
|
||
|
|
|
||
|
|
private:
|
||
|
|
callback_type m_function;
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Hook registry (non-callable view of a hook)
|
||
|
|
*
|
||
|
|
* Callbacks can be assigned to a hook via the corresponding registry,
|
||
|
|
* but the callback cannot be invoked through the registry.
|
||
|
|
*/
|
||
|
|
template<typename... Args>
|
||
|
|
class HookRegistry
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
using hook_type = Hook<Args...>;
|
||
|
|
using callback_type = typename hook_type::callback_type;
|
||
|
|
|
||
|
|
HookRegistry(hook_type& hook) : m_hook(hook) {}
|
||
|
|
|
||
|
|
void operator=(callback_type&& cb)
|
||
|
|
{
|
||
|
|
m_hook = std::move(cb);
|
||
|
|
}
|
||
|
|
|
||
|
|
void operator=(const callback_type& cb)
|
||
|
|
{
|
||
|
|
m_hook = cb;
|
||
|
|
}
|
||
|
|
|
||
|
|
void reset()
|
||
|
|
{
|
||
|
|
m_hook.reset();
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
hook_type& m_hook;
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace vanetza
|
||
|
|
|
||
|
|
#endif /* HOOK_HPP_RNAM6XF4 */
|
||
|
|
|