mirror of
https://github.com/matrix-construct/construct
synced 2024-12-25 15:04:10 +01:00
125 lines
4.2 KiB
C++
125 lines
4.2 KiB
C++
/*
|
|
* charybdis: oh just a little chat server
|
|
* ctx.h: userland context switching (stackful coroutines)
|
|
*
|
|
* Copyright (C) 2016 Charybdis Development Team
|
|
* Copyright (C) 2016 Jason Volk <jason@zemos.net>
|
|
*
|
|
* Permission to use, copy, modify, and/or distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice is present in all copies.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
|
|
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
|
|
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_CTX_CTX_H
|
|
|
|
namespace ircd {
|
|
namespace ctx {
|
|
|
|
struct ctx;
|
|
|
|
//
|
|
// low-level ctx interface exposure
|
|
//
|
|
const uint64_t &id(const ctx &); // Unique ID for context
|
|
string_view name(const ctx &); // User's optional label for context
|
|
const int64_t ¬es(const ctx &); // Peeks at internal semaphore count (you don't need this)
|
|
bool finished(const ctx &); // Context function returned (or exception).
|
|
bool started(const ctx &); // Context was ever entered.
|
|
void interrupt(ctx &); // Interrupt the context for termination.
|
|
bool notify(ctx &); // Increment the semaphore (only library ppl need this)
|
|
|
|
//
|
|
// "this_context" interface relevant to the currently running context
|
|
//
|
|
extern __thread struct ctx *current; // Always set to the currently running context or null
|
|
|
|
// low-level fundamentals
|
|
ctx &cur(); // Convenience for *current (try to use this instead)
|
|
void yield(); // Allow other contexts to run before returning.
|
|
void wait(); // Returns when context notified.
|
|
|
|
// Return remaining time if notified; or <= 0 if not, and timeout thrown on throw overloads
|
|
microseconds wait(const microseconds &, const std::nothrow_t &);
|
|
template<class E, class duration> nothrow_overload<E, duration> wait(const duration &);
|
|
template<class E = timeout, class duration> throw_overload<E, duration> wait(const duration &);
|
|
|
|
// Returns false if notified; true if time point reached, timeout thrown on throw_overloads
|
|
bool wait_until(const time_point &tp, const std::nothrow_t &);
|
|
template<class E> nothrow_overload<E, bool> wait_until(const time_point &tp);
|
|
template<class E = timeout> throw_overload<E> wait_until(const time_point &tp);
|
|
|
|
// Ignores notes. Throws if interrupted.
|
|
void sleep_until(const time_point &tp);
|
|
template<class duration> void sleep(const duration &);
|
|
void sleep(const int &secs);
|
|
|
|
} // namespace ctx
|
|
} // namespace ircd
|
|
|
|
inline void
|
|
ircd::ctx::sleep(const int &secs)
|
|
{
|
|
sleep(seconds(secs));
|
|
}
|
|
|
|
template<class duration>
|
|
void
|
|
ircd::ctx::sleep(const duration &d)
|
|
{
|
|
sleep_until(steady_clock::now() + d);
|
|
}
|
|
|
|
template<class E>
|
|
ircd::throw_overload<E>
|
|
ircd::ctx::wait_until(const time_point &tp)
|
|
{
|
|
if(wait_until<std::nothrow_t>(tp))
|
|
throw E();
|
|
}
|
|
|
|
template<class E>
|
|
ircd::nothrow_overload<E, bool>
|
|
ircd::ctx::wait_until(const time_point &tp)
|
|
{
|
|
return wait_until(tp, std::nothrow);
|
|
}
|
|
|
|
template<class E,
|
|
class duration>
|
|
ircd::throw_overload<E, duration>
|
|
ircd::ctx::wait(const duration &d)
|
|
{
|
|
const auto ret(wait<std::nothrow_t>(d));
|
|
return ret <= duration(0)? throw E() : ret;
|
|
}
|
|
|
|
template<class E,
|
|
class duration>
|
|
ircd::nothrow_overload<E, duration>
|
|
ircd::ctx::wait(const duration &d)
|
|
{
|
|
using std::chrono::duration_cast;
|
|
|
|
const auto ret(wait(duration_cast<microseconds>(d), std::nothrow));
|
|
return duration_cast<duration>(ret);
|
|
}
|
|
|
|
inline ircd::ctx::ctx &
|
|
ircd::ctx::cur()
|
|
{
|
|
assert(current);
|
|
return *current;
|
|
}
|