Files
mpd/src/thread/Id.hxx
2023-03-06 14:59:48 +01:00

82 lines
1.5 KiB
C++

// SPDX-License-Identifier: BSD-2-Clause
// author: Max Kellermann <max.kellermann@gmail.com>
#ifndef THREAD_ID_HXX
#define THREAD_ID_HXX
#ifdef _WIN32
#include <processthreadsapi.h>
#else
#include <pthread.h>
#endif
/**
* A low-level identification for a thread. Designed to work with
* existing threads, such as the main thread. Mostly useful for
* debugging code.
*/
class ThreadId {
#ifdef _WIN32
DWORD id;
#else
pthread_t id;
#endif
public:
/**
* No initialisation.
*/
ThreadId() noexcept = default;
#ifdef _WIN32
constexpr ThreadId(DWORD _id) noexcept:id(_id) {}
#else
constexpr ThreadId(pthread_t _id) noexcept:id(_id) {}
#endif
static constexpr ThreadId Null() noexcept {
#ifdef _WIN32
return 0;
#else
return pthread_t();
#endif
}
[[gnu::pure]]
bool IsNull() const noexcept {
return *this == Null();
}
/**
* Return the current thread's id .
*/
[[gnu::pure]]
static const ThreadId GetCurrent() noexcept {
#ifdef _WIN32
return ::GetCurrentThreadId();
#else
return pthread_self();
#endif
}
[[gnu::pure]]
bool operator==(const ThreadId &other) const noexcept {
/* note: not using pthread_equal() because that
function "is undefined if either thread ID is not
valid so we can't safely use it on
default-constructed values" (comment from
libstdc++) - and if both libstdc++ and libc++ get
away with this, we can do it as well */
return id == other.id;
}
/**
* Check if this thread is the current thread.
*/
bool IsInside() const noexcept {
return *this == GetCurrent();
}
};
#endif