1   
//
1   
//
2   
// Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.com)
2   
// Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.com)
3   
//
3   
//
4   
// Distributed under the Boost Software License, Version 1.0. (See accompanying
4   
// Distributed under the Boost Software License, Version 1.0. (See accompanying
5   
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5   
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6   
//
6   
//
7   
// Official repository: https://github.com/cppalliance/capy
7   
// Official repository: https://github.com/cppalliance/capy
8   
//
8   
//
9  
9  
10   
#ifndef BOOST_CAPY_RUN_HPP
10   
#ifndef BOOST_CAPY_RUN_HPP
11   
#define BOOST_CAPY_RUN_HPP
11   
#define BOOST_CAPY_RUN_HPP
12  
12  
13   
#include <boost/capy/detail/config.hpp>
13   
#include <boost/capy/detail/config.hpp>
14   
#include <boost/capy/detail/await_suspend_helper.hpp>
14   
#include <boost/capy/detail/await_suspend_helper.hpp>
15   
#include <boost/capy/detail/run.hpp>
15   
#include <boost/capy/detail/run.hpp>
16   
#include <boost/capy/concept/executor.hpp>
16   
#include <boost/capy/concept/executor.hpp>
17   
#include <boost/capy/concept/io_runnable.hpp>
17   
#include <boost/capy/concept/io_runnable.hpp>
18   
#include <boost/capy/ex/executor_ref.hpp>
18   
#include <boost/capy/ex/executor_ref.hpp>
19   
#include <coroutine>
19   
#include <coroutine>
20   
#include <boost/capy/ex/frame_allocator.hpp>
20   
#include <boost/capy/ex/frame_allocator.hpp>
21   
#include <boost/capy/ex/io_env.hpp>
21   
#include <boost/capy/ex/io_env.hpp>
22  
22  
23   
#include <memory_resource>
23   
#include <memory_resource>
24   
#include <stop_token>
24   
#include <stop_token>
25   
#include <type_traits>
25   
#include <type_traits>
26   
#include <utility>
26   
#include <utility>
27   
#include <variant>
27   
#include <variant>
28  
28  
29   
/*
29   
/*
30   
    Allocator Lifetime Strategy
30   
    Allocator Lifetime Strategy
31   
    ===========================
31   
    ===========================
32  
32  
33   
    When using run() with a custom allocator:
33   
    When using run() with a custom allocator:
34  
34  
35   
        co_await run(ex, alloc)(my_task());
35   
        co_await run(ex, alloc)(my_task());
36  
36  
37   
    The evaluation order is:
37   
    The evaluation order is:
38   
        1. run(ex, alloc) creates a temporary wrapper
38   
        1. run(ex, alloc) creates a temporary wrapper
39   
        2. my_task() allocates its coroutine frame using TLS
39   
        2. my_task() allocates its coroutine frame using TLS
40   
        3. operator() returns an awaitable
40   
        3. operator() returns an awaitable
41   
        4. Wrapper temporary is DESTROYED
41   
        4. Wrapper temporary is DESTROYED
42   
        5. co_await suspends caller, resumes task
42   
        5. co_await suspends caller, resumes task
43   
        6. Task body executes (wrapper is already dead!)
43   
        6. Task body executes (wrapper is already dead!)
44  
44  
45   
    Problem: The wrapper's frame_memory_resource dies before the task
45   
    Problem: The wrapper's frame_memory_resource dies before the task
46   
    body runs. When initial_suspend::await_resume() restores TLS from
46   
    body runs. When initial_suspend::await_resume() restores TLS from
47   
    the saved pointer, it would point to dead memory.
47   
    the saved pointer, it would point to dead memory.
48  
48  
49   
    Solution: Store a COPY of the allocator in the awaitable (not just
49   
    Solution: Store a COPY of the allocator in the awaitable (not just
50   
    the wrapper). The co_await mechanism extends the awaitable's lifetime
50   
    the wrapper). The co_await mechanism extends the awaitable's lifetime
51   
    until the await completes. In await_suspend, we overwrite the promise's
51   
    until the await completes. In await_suspend, we overwrite the promise's
52   
    saved frame_allocator pointer to point to the awaitable's resource.
52   
    saved frame_allocator pointer to point to the awaitable's resource.
53  
53  
54   
    This works because standard allocator copies are equivalent - memory
54   
    This works because standard allocator copies are equivalent - memory
55   
    allocated with one copy can be deallocated with another copy. The
55   
    allocated with one copy can be deallocated with another copy. The
56   
    task's own frame uses the footer-stored pointer (safe), while nested
56   
    task's own frame uses the footer-stored pointer (safe), while nested
57   
    task creation uses TLS pointing to the awaitable's resource (also safe).
57   
    task creation uses TLS pointing to the awaitable's resource (also safe).
58   
*/
58   
*/
59  
59  
60   
namespace boost::capy::detail {
60   
namespace boost::capy::detail {
61  
61  
 
62 + 
//----------------------------------------------------------
 
63 + 
//
 
64 + 
// dispatch_trampoline - cross-executor dispatch
 
65 + 
//
 
66 + 
//----------------------------------------------------------
 
67 +
62   
/** Minimal coroutine that dispatches through the caller's executor.
68   
/** Minimal coroutine that dispatches through the caller's executor.
63  
69  
64   
    Sits between the inner task and the parent when executors
70   
    Sits between the inner task and the parent when executors
65   
    diverge. The inner task's `final_suspend` resumes this
71   
    diverge. The inner task's `final_suspend` resumes this
66   
    trampoline via symmetric transfer. The trampoline's own
72   
    trampoline via symmetric transfer. The trampoline's own
67   
    `final_suspend` dispatches the parent through the caller's
73   
    `final_suspend` dispatches the parent through the caller's
68   
    executor to restore the correct execution context.
74   
    executor to restore the correct execution context.
69  
75  
70   
    The trampoline never touches the task's result.
76   
    The trampoline never touches the task's result.
71   
*/
77   
*/
72   
struct dispatch_trampoline
78   
struct dispatch_trampoline
73   
{
79   
{
74   
    struct promise_type
80   
    struct promise_type
75   
    {
81   
    {
76   
        executor_ref caller_ex_;
82   
        executor_ref caller_ex_;
77   
        std::coroutine_handle<> parent_;
83   
        std::coroutine_handle<> parent_;
78  
84  
79   
        dispatch_trampoline get_return_object() noexcept
85   
        dispatch_trampoline get_return_object() noexcept
80   
        {
86   
        {
81   
            return dispatch_trampoline{
87   
            return dispatch_trampoline{
82   
                std::coroutine_handle<promise_type>::from_promise(*this)};
88   
                std::coroutine_handle<promise_type>::from_promise(*this)};
83   
        }
89   
        }
84  
90  
85   
        std::suspend_always initial_suspend() noexcept { return {}; }
91   
        std::suspend_always initial_suspend() noexcept { return {}; }
86  
92  
87   
        auto final_suspend() noexcept
93   
        auto final_suspend() noexcept
88   
        {
94   
        {
89   
            struct awaiter
95   
            struct awaiter
90   
            {
96   
            {
91   
                promise_type* p_;
97   
                promise_type* p_;
92   
                bool await_ready() const noexcept { return false; }
98   
                bool await_ready() const noexcept { return false; }
93  
99  
94   
                auto await_suspend(
100   
                auto await_suspend(
95   
                    std::coroutine_handle<>) noexcept
101   
                    std::coroutine_handle<>) noexcept
96   
                {
102   
                {
97   
                    return detail::symmetric_transfer(
103   
                    return detail::symmetric_transfer(
98   
                        p_->caller_ex_.dispatch(p_->parent_));
104   
                        p_->caller_ex_.dispatch(p_->parent_));
99   
                }
105   
                }
100  
106  
101   
                void await_resume() const noexcept {}
107   
                void await_resume() const noexcept {}
102   
            };
108   
            };
103   
            return awaiter{this};
109   
            return awaiter{this};
104   
        }
110   
        }
105  
111  
106   
        void return_void() noexcept {}
112   
        void return_void() noexcept {}
107   
        void unhandled_exception() noexcept {}
113   
        void unhandled_exception() noexcept {}
108   
    };
114   
    };
109  
115  
110   
    std::coroutine_handle<promise_type> h_{nullptr};
116   
    std::coroutine_handle<promise_type> h_{nullptr};
111  
117  
112   
    dispatch_trampoline() noexcept = default;
118   
    dispatch_trampoline() noexcept = default;
113  
119  
114   
    ~dispatch_trampoline()
120   
    ~dispatch_trampoline()
115   
    {
121   
    {
116   
        if(h_) h_.destroy();
122   
        if(h_) h_.destroy();
117   
    }
123   
    }
118  
124  
119   
    dispatch_trampoline(dispatch_trampoline const&) = delete;
125   
    dispatch_trampoline(dispatch_trampoline const&) = delete;
120   
    dispatch_trampoline& operator=(dispatch_trampoline const&) = delete;
126   
    dispatch_trampoline& operator=(dispatch_trampoline const&) = delete;
121  
127  
122   
    dispatch_trampoline(dispatch_trampoline&& o) noexcept
128   
    dispatch_trampoline(dispatch_trampoline&& o) noexcept
123   
        : h_(std::exchange(o.h_, nullptr)) {}
129   
        : h_(std::exchange(o.h_, nullptr)) {}
124  
130  
125   
    dispatch_trampoline& operator=(dispatch_trampoline&& o) noexcept
131   
    dispatch_trampoline& operator=(dispatch_trampoline&& o) noexcept
126   
    {
132   
    {
127   
        if(this != &o)
133   
        if(this != &o)
128   
        {
134   
        {
129   
            if(h_) h_.destroy();
135   
            if(h_) h_.destroy();
130   
            h_ = std::exchange(o.h_, nullptr);
136   
            h_ = std::exchange(o.h_, nullptr);
131   
        }
137   
        }
132   
        return *this;
138   
        return *this;
133   
    }
139   
    }
134  
140  
135   
private:
141   
private:
136   
    explicit dispatch_trampoline(std::coroutine_handle<promise_type> h) noexcept
142   
    explicit dispatch_trampoline(std::coroutine_handle<promise_type> h) noexcept
137   
        : h_(h) {}
143   
        : h_(h) {}
138   
};
144   
};
139  
145  
140   
inline dispatch_trampoline make_dispatch_trampoline()
146   
inline dispatch_trampoline make_dispatch_trampoline()
141   
{
147   
{
142   
    co_return;
148   
    co_return;
143   
}
149   
}
144  
150  
 
151 + 
//----------------------------------------------------------
 
152 + 
//
 
153 + 
// run_awaitable_ex - with executor (executor switch)
 
154 + 
//
 
155 + 
//----------------------------------------------------------
 
156 +
145   
/** Awaitable that binds an IoRunnable to a specific executor.
157   
/** Awaitable that binds an IoRunnable to a specific executor.
146  
158  
147   
    Stores the executor and inner task by value. When co_awaited, the
159   
    Stores the executor and inner task by value. When co_awaited, the
148   
    co_await expression's lifetime extension keeps both alive for the
160   
    co_await expression's lifetime extension keeps both alive for the
149   
    duration of the operation.
161   
    duration of the operation.
150  
162  
151   
    A dispatch trampoline handles the executor switch on completion:
163   
    A dispatch trampoline handles the executor switch on completion:
152   
    the inner task's `final_suspend` resumes the trampoline, which
164   
    the inner task's `final_suspend` resumes the trampoline, which
153   
    dispatches back through the caller's executor.
165   
    dispatches back through the caller's executor.
154  
166  
155   
    The `io_env` is owned by this awaitable and is guaranteed to
167   
    The `io_env` is owned by this awaitable and is guaranteed to
156   
    outlive the inner task and all awaitables in its chain. Awaitables
168   
    outlive the inner task and all awaitables in its chain. Awaitables
157   
    may store `io_env const*` without concern for dangling references.
169   
    may store `io_env const*` without concern for dangling references.
158  
170  
159   
    @tparam Task The IoRunnable type
171   
    @tparam Task The IoRunnable type
160   
    @tparam Ex The executor type
172   
    @tparam Ex The executor type
161   
    @tparam InheritStopToken If true, inherit caller's stop token
173   
    @tparam InheritStopToken If true, inherit caller's stop token
162   
    @tparam Alloc The allocator type (void for no allocator)
174   
    @tparam Alloc The allocator type (void for no allocator)
163   
*/
175   
*/
164   
template<IoRunnable Task, Executor Ex, bool InheritStopToken, class Alloc = void>
176   
template<IoRunnable Task, Executor Ex, bool InheritStopToken, class Alloc = void>
165   
struct [[nodiscard]] run_awaitable_ex
177   
struct [[nodiscard]] run_awaitable_ex
166   
{
178   
{
167   
    Ex ex_;
179   
    Ex ex_;
168   
    frame_memory_resource<Alloc> resource_;
180   
    frame_memory_resource<Alloc> resource_;
169   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
181   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
170   
    io_env env_;
182   
    io_env env_;
171   
    dispatch_trampoline tr_;
183   
    dispatch_trampoline tr_;
172   
    Task inner_;  // Last: destroyed first, while env_ is still valid
184   
    Task inner_;  // Last: destroyed first, while env_ is still valid
173  
185  
174   
    // void allocator, inherit stop token
186   
    // void allocator, inherit stop token
175   
    run_awaitable_ex(Ex ex, Task inner)
187   
    run_awaitable_ex(Ex ex, Task inner)
176   
        requires (InheritStopToken && std::is_void_v<Alloc>)
188   
        requires (InheritStopToken && std::is_void_v<Alloc>)
177   
        : ex_(std::move(ex))
189   
        : ex_(std::move(ex))
178   
        , inner_(std::move(inner))
190   
        , inner_(std::move(inner))
179   
    {
191   
    {
180   
    }
192   
    }
181  
193  
182   
    // void allocator, explicit stop token
194   
    // void allocator, explicit stop token
183   
    run_awaitable_ex(Ex ex, Task inner, std::stop_token st)
195   
    run_awaitable_ex(Ex ex, Task inner, std::stop_token st)
184   
        requires (!InheritStopToken && std::is_void_v<Alloc>)
196   
        requires (!InheritStopToken && std::is_void_v<Alloc>)
185   
        : ex_(std::move(ex))
197   
        : ex_(std::move(ex))
186   
        , st_(std::move(st))
198   
        , st_(std::move(st))
187   
        , inner_(std::move(inner))
199   
        , inner_(std::move(inner))
188   
    {
200   
    {
189   
    }
201   
    }
190  
202  
191   
    // with allocator, inherit stop token (use template to avoid void parameter)
203   
    // with allocator, inherit stop token (use template to avoid void parameter)
192   
    template<class A>
204   
    template<class A>
193   
        requires (InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
205   
        requires (InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
194   
    run_awaitable_ex(Ex ex, A alloc, Task inner)
206   
    run_awaitable_ex(Ex ex, A alloc, Task inner)
195   
        : ex_(std::move(ex))
207   
        : ex_(std::move(ex))
196   
        , resource_(std::move(alloc))
208   
        , resource_(std::move(alloc))
197   
        , inner_(std::move(inner))
209   
        , inner_(std::move(inner))
198   
    {
210   
    {
199   
    }
211   
    }
200  
212  
201   
    // with allocator, explicit stop token (use template to avoid void parameter)
213   
    // with allocator, explicit stop token (use template to avoid void parameter)
202   
    template<class A>
214   
    template<class A>
203   
        requires (!InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
215   
        requires (!InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
204   
    run_awaitable_ex(Ex ex, A alloc, Task inner, std::stop_token st)
216   
    run_awaitable_ex(Ex ex, A alloc, Task inner, std::stop_token st)
205   
        : ex_(std::move(ex))
217   
        : ex_(std::move(ex))
206   
        , resource_(std::move(alloc))
218   
        , resource_(std::move(alloc))
207   
        , st_(std::move(st))
219   
        , st_(std::move(st))
208   
        , inner_(std::move(inner))
220   
        , inner_(std::move(inner))
209   
    {
221   
    {
210   
    }
222   
    }
211  
223  
212   
    bool await_ready() const noexcept
224   
    bool await_ready() const noexcept
213   
    {
225   
    {
214   
        return inner_.await_ready();
226   
        return inner_.await_ready();
215   
    }
227   
    }
216  
228  
217   
    decltype(auto) await_resume()
229   
    decltype(auto) await_resume()
218   
    {
230   
    {
219   
        return inner_.await_resume();
231   
        return inner_.await_resume();
220   
    }
232   
    }
221  
233  
222   
    std::coroutine_handle<> await_suspend(std::coroutine_handle<> cont, io_env const* caller_env)
234   
    std::coroutine_handle<> await_suspend(std::coroutine_handle<> cont, io_env const* caller_env)
223   
    {
235   
    {
224   
        tr_ = make_dispatch_trampoline();
236   
        tr_ = make_dispatch_trampoline();
225   
        tr_.h_.promise().caller_ex_ = caller_env->executor;
237   
        tr_.h_.promise().caller_ex_ = caller_env->executor;
226   
        tr_.h_.promise().parent_ = cont;
238   
        tr_.h_.promise().parent_ = cont;
227  
239  
228   
        auto h = inner_.handle();
240   
        auto h = inner_.handle();
229   
        auto& p = h.promise();
241   
        auto& p = h.promise();
230   
        p.set_continuation(tr_.h_);
242   
        p.set_continuation(tr_.h_);
231  
243  
232   
        env_.executor = ex_;
244   
        env_.executor = ex_;
233   
        if constexpr (InheritStopToken)
245   
        if constexpr (InheritStopToken)
234   
            env_.stop_token = caller_env->stop_token;
246   
            env_.stop_token = caller_env->stop_token;
235   
        else
247   
        else
236   
            env_.stop_token = st_;
248   
            env_.stop_token = st_;
237  
249  
238   
        if constexpr (!std::is_void_v<Alloc>)
250   
        if constexpr (!std::is_void_v<Alloc>)
239   
            env_.frame_allocator = resource_.get();
251   
            env_.frame_allocator = resource_.get();
240   
        else
252   
        else
241   
            env_.frame_allocator = caller_env->frame_allocator;
253   
            env_.frame_allocator = caller_env->frame_allocator;
242  
254  
243   
        p.set_environment(&env_);
255   
        p.set_environment(&env_);
244   
        return h;
256   
        return h;
245   
    }
257   
    }
246  
258  
247   
    // Non-copyable
259   
    // Non-copyable
248   
    run_awaitable_ex(run_awaitable_ex const&) = delete;
260   
    run_awaitable_ex(run_awaitable_ex const&) = delete;
249   
    run_awaitable_ex& operator=(run_awaitable_ex const&) = delete;
261   
    run_awaitable_ex& operator=(run_awaitable_ex const&) = delete;
250  
262  
251   
    // Movable (no noexcept - Task may throw)
263   
    // Movable (no noexcept - Task may throw)
252   
    run_awaitable_ex(run_awaitable_ex&&) = default;
264   
    run_awaitable_ex(run_awaitable_ex&&) = default;
253   
    run_awaitable_ex& operator=(run_awaitable_ex&&) = default;
265   
    run_awaitable_ex& operator=(run_awaitable_ex&&) = default;
254   
};
266   
};
255  
267  
 
268 + 
//----------------------------------------------------------
 
269 + 
//
 
270 + 
// run_awaitable - no executor (inherits caller's executor)
 
271 + 
//
 
272 + 
//----------------------------------------------------------
 
273 +
256   
/** Awaitable that runs a task with optional stop_token override.
274   
/** Awaitable that runs a task with optional stop_token override.
257  
275  
258   
    Does NOT store an executor - the task inherits the caller's executor
276   
    Does NOT store an executor - the task inherits the caller's executor
259   
    directly. Executors always match, so no dispatch trampoline is needed.
277   
    directly. Executors always match, so no dispatch trampoline is needed.
260   
    The inner task's `final_suspend` resumes the parent directly via
278   
    The inner task's `final_suspend` resumes the parent directly via
261   
    unconditional symmetric transfer.
279   
    unconditional symmetric transfer.
262  
280  
263   
    @tparam Task The IoRunnable type
281   
    @tparam Task The IoRunnable type
264   
    @tparam InheritStopToken If true, inherit caller's stop token
282   
    @tparam InheritStopToken If true, inherit caller's stop token
265   
    @tparam Alloc The allocator type (void for no allocator)
283   
    @tparam Alloc The allocator type (void for no allocator)
266   
*/
284   
*/
267   
template<IoRunnable Task, bool InheritStopToken, class Alloc = void>
285   
template<IoRunnable Task, bool InheritStopToken, class Alloc = void>
268   
struct [[nodiscard]] run_awaitable
286   
struct [[nodiscard]] run_awaitable
269   
{
287   
{
270   
    frame_memory_resource<Alloc> resource_;
288   
    frame_memory_resource<Alloc> resource_;
271   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
289   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
272   
    io_env env_;
290   
    io_env env_;
273   
    Task inner_;  // Last: destroyed first, while env_ is still valid
291   
    Task inner_;  // Last: destroyed first, while env_ is still valid
274  
292  
275   
    // void allocator, inherit stop token
293   
    // void allocator, inherit stop token
276   
    explicit run_awaitable(Task inner)
294   
    explicit run_awaitable(Task inner)
277   
        requires (InheritStopToken && std::is_void_v<Alloc>)
295   
        requires (InheritStopToken && std::is_void_v<Alloc>)
278   
        : inner_(std::move(inner))
296   
        : inner_(std::move(inner))
279   
    {
297   
    {
280   
    }
298   
    }
281  
299  
282   
    // void allocator, explicit stop token
300   
    // void allocator, explicit stop token
283   
    run_awaitable(Task inner, std::stop_token st)
301   
    run_awaitable(Task inner, std::stop_token st)
284   
        requires (!InheritStopToken && std::is_void_v<Alloc>)
302   
        requires (!InheritStopToken && std::is_void_v<Alloc>)
285   
        : st_(std::move(st))
303   
        : st_(std::move(st))
286   
        , inner_(std::move(inner))
304   
        , inner_(std::move(inner))
287   
    {
305   
    {
288   
    }
306   
    }
289  
307  
290   
    // with allocator, inherit stop token (use template to avoid void parameter)
308   
    // with allocator, inherit stop token (use template to avoid void parameter)
291   
    template<class A>
309   
    template<class A>
292   
        requires (InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
310   
        requires (InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
293   
    run_awaitable(A alloc, Task inner)
311   
    run_awaitable(A alloc, Task inner)
294   
        : resource_(std::move(alloc))
312   
        : resource_(std::move(alloc))
295   
        , inner_(std::move(inner))
313   
        , inner_(std::move(inner))
296   
    {
314   
    {
297   
    }
315   
    }
298  
316  
299   
    // with allocator, explicit stop token (use template to avoid void parameter)
317   
    // with allocator, explicit stop token (use template to avoid void parameter)
300   
    template<class A>
318   
    template<class A>
301   
        requires (!InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
319   
        requires (!InheritStopToken && !std::is_void_v<Alloc> && std::same_as<A, Alloc>)
302   
    run_awaitable(A alloc, Task inner, std::stop_token st)
320   
    run_awaitable(A alloc, Task inner, std::stop_token st)
303   
        : resource_(std::move(alloc))
321   
        : resource_(std::move(alloc))
304   
        , st_(std::move(st))
322   
        , st_(std::move(st))
305   
        , inner_(std::move(inner))
323   
        , inner_(std::move(inner))
306   
    {
324   
    {
307   
    }
325   
    }
308  
326  
309   
    bool await_ready() const noexcept
327   
    bool await_ready() const noexcept
310   
    {
328   
    {
311   
        return inner_.await_ready();
329   
        return inner_.await_ready();
312   
    }
330   
    }
313  
331  
314   
    decltype(auto) await_resume()
332   
    decltype(auto) await_resume()
315   
    {
333   
    {
316   
        return inner_.await_resume();
334   
        return inner_.await_resume();
317   
    }
335   
    }
318  
336  
319   
    std::coroutine_handle<> await_suspend(std::coroutine_handle<> cont, io_env const* caller_env)
337   
    std::coroutine_handle<> await_suspend(std::coroutine_handle<> cont, io_env const* caller_env)
320   
    {
338   
    {
321   
        auto h = inner_.handle();
339   
        auto h = inner_.handle();
322   
        auto& p = h.promise();
340   
        auto& p = h.promise();
323   
        p.set_continuation(cont);
341   
        p.set_continuation(cont);
324  
342  
325   
        env_.executor = caller_env->executor;
343   
        env_.executor = caller_env->executor;
326   
        if constexpr (InheritStopToken)
344   
        if constexpr (InheritStopToken)
327   
            env_.stop_token = caller_env->stop_token;
345   
            env_.stop_token = caller_env->stop_token;
328   
        else
346   
        else
329   
            env_.stop_token = st_;
347   
            env_.stop_token = st_;
330  
348  
331   
        if constexpr (!std::is_void_v<Alloc>)
349   
        if constexpr (!std::is_void_v<Alloc>)
332   
            env_.frame_allocator = resource_.get();
350   
            env_.frame_allocator = resource_.get();
333   
        else
351   
        else
334   
            env_.frame_allocator = caller_env->frame_allocator;
352   
            env_.frame_allocator = caller_env->frame_allocator;
335  
353  
336   
        p.set_environment(&env_);
354   
        p.set_environment(&env_);
337   
        return h;
355   
        return h;
338   
    }
356   
    }
339  
357  
340   
    // Non-copyable
358   
    // Non-copyable
341   
    run_awaitable(run_awaitable const&) = delete;
359   
    run_awaitable(run_awaitable const&) = delete;
342   
    run_awaitable& operator=(run_awaitable const&) = delete;
360   
    run_awaitable& operator=(run_awaitable const&) = delete;
343  
361  
344   
    // Movable (no noexcept - Task may throw)
362   
    // Movable (no noexcept - Task may throw)
345   
    run_awaitable(run_awaitable&&) = default;
363   
    run_awaitable(run_awaitable&&) = default;
346   
    run_awaitable& operator=(run_awaitable&&) = default;
364   
    run_awaitable& operator=(run_awaitable&&) = default;
347   
};
365   
};
348  
366  
 
367 + 
//----------------------------------------------------------
 
368 + 
//
 
369 + 
// run_wrapper_ex - with executor
 
370 + 
//
 
371 + 
//----------------------------------------------------------
 
372 +
349   
/** Wrapper returned by run(ex, ...) that accepts a task for execution.
373   
/** Wrapper returned by run(ex, ...) that accepts a task for execution.
350  
374  
351   
    @tparam Ex The executor type.
375   
    @tparam Ex The executor type.
352   
    @tparam InheritStopToken If true, inherit caller's stop token.
376   
    @tparam InheritStopToken If true, inherit caller's stop token.
353   
    @tparam Alloc The allocator type (void for no allocator).
377   
    @tparam Alloc The allocator type (void for no allocator).
354   
*/
378   
*/
355   
template<Executor Ex, bool InheritStopToken, class Alloc>
379   
template<Executor Ex, bool InheritStopToken, class Alloc>
356   
class [[nodiscard]] run_wrapper_ex
380   
class [[nodiscard]] run_wrapper_ex
357   
{
381   
{
358   
    Ex ex_;
382   
    Ex ex_;
359   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
383   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
360   
    frame_memory_resource<Alloc> resource_;
384   
    frame_memory_resource<Alloc> resource_;
361   
    Alloc alloc_;  // Copy to pass to awaitable
385   
    Alloc alloc_;  // Copy to pass to awaitable
362  
386  
363   
public:
387   
public:
364   
    run_wrapper_ex(Ex ex, Alloc alloc)
388   
    run_wrapper_ex(Ex ex, Alloc alloc)
365   
        requires InheritStopToken
389   
        requires InheritStopToken
366   
        : ex_(std::move(ex))
390   
        : ex_(std::move(ex))
367   
        , resource_(alloc)
391   
        , resource_(alloc)
368   
        , alloc_(std::move(alloc))
392   
        , alloc_(std::move(alloc))
369   
    {
393   
    {
370   
        set_current_frame_allocator(&resource_);
394   
        set_current_frame_allocator(&resource_);
371   
    }
395   
    }
372  
396  
373   
    run_wrapper_ex(Ex ex, std::stop_token st, Alloc alloc)
397   
    run_wrapper_ex(Ex ex, std::stop_token st, Alloc alloc)
374   
        requires (!InheritStopToken)
398   
        requires (!InheritStopToken)
375   
        : ex_(std::move(ex))
399   
        : ex_(std::move(ex))
376   
        , st_(std::move(st))
400   
        , st_(std::move(st))
377   
        , resource_(alloc)
401   
        , resource_(alloc)
378   
        , alloc_(std::move(alloc))
402   
        , alloc_(std::move(alloc))
379   
    {
403   
    {
380   
        set_current_frame_allocator(&resource_);
404   
        set_current_frame_allocator(&resource_);
381   
    }
405   
    }
382  
406  
383   
    // Non-copyable, non-movable (must be used immediately)
407   
    // Non-copyable, non-movable (must be used immediately)
384   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
408   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
385   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
409   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
386   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
410   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
387   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
411   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
388  
412  
389   
    template<IoRunnable Task>
413   
    template<IoRunnable Task>
390   
    [[nodiscard]] auto operator()(Task t) &&
414   
    [[nodiscard]] auto operator()(Task t) &&
391   
    {
415   
    {
392   
        if constexpr (InheritStopToken)
416   
        if constexpr (InheritStopToken)
393   
            return run_awaitable_ex<Task, Ex, true, Alloc>{
417   
            return run_awaitable_ex<Task, Ex, true, Alloc>{
394   
                std::move(ex_), std::move(alloc_), std::move(t)};
418   
                std::move(ex_), std::move(alloc_), std::move(t)};
395   
        else
419   
        else
396   
            return run_awaitable_ex<Task, Ex, false, Alloc>{
420   
            return run_awaitable_ex<Task, Ex, false, Alloc>{
397   
                std::move(ex_), std::move(alloc_), std::move(t), std::move(st_)};
421   
                std::move(ex_), std::move(alloc_), std::move(t), std::move(st_)};
398   
    }
422   
    }
399   
};
423   
};
400  
424  
401   
/// Specialization for memory_resource* - stores pointer directly.
425   
/// Specialization for memory_resource* - stores pointer directly.
402   
template<Executor Ex, bool InheritStopToken>
426   
template<Executor Ex, bool InheritStopToken>
403   
class [[nodiscard]] run_wrapper_ex<Ex, InheritStopToken, std::pmr::memory_resource*>
427   
class [[nodiscard]] run_wrapper_ex<Ex, InheritStopToken, std::pmr::memory_resource*>
404   
{
428   
{
405   
    Ex ex_;
429   
    Ex ex_;
406   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
430   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
407   
    std::pmr::memory_resource* mr_;
431   
    std::pmr::memory_resource* mr_;
408  
432  
409   
public:
433   
public:
410   
    run_wrapper_ex(Ex ex, std::pmr::memory_resource* mr)
434   
    run_wrapper_ex(Ex ex, std::pmr::memory_resource* mr)
411   
        requires InheritStopToken
435   
        requires InheritStopToken
412   
        : ex_(std::move(ex))
436   
        : ex_(std::move(ex))
413   
        , mr_(mr)
437   
        , mr_(mr)
414   
    {
438   
    {
415   
        set_current_frame_allocator(mr_);
439   
        set_current_frame_allocator(mr_);
416   
    }
440   
    }
417  
441  
418   
    run_wrapper_ex(Ex ex, std::stop_token st, std::pmr::memory_resource* mr)
442   
    run_wrapper_ex(Ex ex, std::stop_token st, std::pmr::memory_resource* mr)
419   
        requires (!InheritStopToken)
443   
        requires (!InheritStopToken)
420   
        : ex_(std::move(ex))
444   
        : ex_(std::move(ex))
421   
        , st_(std::move(st))
445   
        , st_(std::move(st))
422   
        , mr_(mr)
446   
        , mr_(mr)
423   
    {
447   
    {
424   
        set_current_frame_allocator(mr_);
448   
        set_current_frame_allocator(mr_);
425   
    }
449   
    }
426  
450  
427   
    // Non-copyable, non-movable (must be used immediately)
451   
    // Non-copyable, non-movable (must be used immediately)
428   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
452   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
429   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
453   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
430   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
454   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
431   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
455   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
432  
456  
433   
    template<IoRunnable Task>
457   
    template<IoRunnable Task>
434   
    [[nodiscard]] auto operator()(Task t) &&
458   
    [[nodiscard]] auto operator()(Task t) &&
435   
    {
459   
    {
436   
        if constexpr (InheritStopToken)
460   
        if constexpr (InheritStopToken)
437   
            return run_awaitable_ex<Task, Ex, true, std::pmr::memory_resource*>{
461   
            return run_awaitable_ex<Task, Ex, true, std::pmr::memory_resource*>{
438   
                std::move(ex_), mr_, std::move(t)};
462   
                std::move(ex_), mr_, std::move(t)};
439   
        else
463   
        else
440   
            return run_awaitable_ex<Task, Ex, false, std::pmr::memory_resource*>{
464   
            return run_awaitable_ex<Task, Ex, false, std::pmr::memory_resource*>{
441   
                std::move(ex_), mr_, std::move(t), std::move(st_)};
465   
                std::move(ex_), mr_, std::move(t), std::move(st_)};
442   
    }
466   
    }
443   
};
467   
};
444  
468  
445   
/// Specialization for no allocator (void).
469   
/// Specialization for no allocator (void).
446   
template<Executor Ex, bool InheritStopToken>
470   
template<Executor Ex, bool InheritStopToken>
447   
class [[nodiscard]] run_wrapper_ex<Ex, InheritStopToken, void>
471   
class [[nodiscard]] run_wrapper_ex<Ex, InheritStopToken, void>
448   
{
472   
{
449   
    Ex ex_;
473   
    Ex ex_;
450   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
474   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
451  
475  
452   
public:
476   
public:
453   
    explicit run_wrapper_ex(Ex ex)
477   
    explicit run_wrapper_ex(Ex ex)
454   
        requires InheritStopToken
478   
        requires InheritStopToken
455   
        : ex_(std::move(ex))
479   
        : ex_(std::move(ex))
456   
    {
480   
    {
457   
    }
481   
    }
458  
482  
459   
    run_wrapper_ex(Ex ex, std::stop_token st)
483   
    run_wrapper_ex(Ex ex, std::stop_token st)
460   
        requires (!InheritStopToken)
484   
        requires (!InheritStopToken)
461   
        : ex_(std::move(ex))
485   
        : ex_(std::move(ex))
462   
        , st_(std::move(st))
486   
        , st_(std::move(st))
463   
    {
487   
    {
464   
    }
488   
    }
465  
489  
466   
    // Non-copyable, non-movable (must be used immediately)
490   
    // Non-copyable, non-movable (must be used immediately)
467   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
491   
    run_wrapper_ex(run_wrapper_ex const&) = delete;
468   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
492   
    run_wrapper_ex(run_wrapper_ex&&) = delete;
469   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
493   
    run_wrapper_ex& operator=(run_wrapper_ex const&) = delete;
470   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
494   
    run_wrapper_ex& operator=(run_wrapper_ex&&) = delete;
471  
495  
472   
    template<IoRunnable Task>
496   
    template<IoRunnable Task>
473   
    [[nodiscard]] auto operator()(Task t) &&
497   
    [[nodiscard]] auto operator()(Task t) &&
474   
    {
498   
    {
475   
        if constexpr (InheritStopToken)
499   
        if constexpr (InheritStopToken)
476   
            return run_awaitable_ex<Task, Ex, true>{
500   
            return run_awaitable_ex<Task, Ex, true>{
477   
                std::move(ex_), std::move(t)};
501   
                std::move(ex_), std::move(t)};
478   
        else
502   
        else
479   
            return run_awaitable_ex<Task, Ex, false>{
503   
            return run_awaitable_ex<Task, Ex, false>{
480   
                std::move(ex_), std::move(t), std::move(st_)};
504   
                std::move(ex_), std::move(t), std::move(st_)};
481   
    }
505   
    }
482   
};
506   
};
483  
507  
 
508 + 
//----------------------------------------------------------
 
509 + 
//
 
510 + 
// run_wrapper - no executor (inherits caller's executor)
 
511 + 
//
 
512 + 
//----------------------------------------------------------
 
513 +
484   
/** Wrapper returned by run(st) or run(alloc) that accepts a task.
514   
/** Wrapper returned by run(st) or run(alloc) that accepts a task.
485  
515  
486   
    @tparam InheritStopToken If true, inherit caller's stop token.
516   
    @tparam InheritStopToken If true, inherit caller's stop token.
487   
    @tparam Alloc The allocator type (void for no allocator).
517   
    @tparam Alloc The allocator type (void for no allocator).
488   
*/
518   
*/
489   
template<bool InheritStopToken, class Alloc>
519   
template<bool InheritStopToken, class Alloc>
490   
class [[nodiscard]] run_wrapper
520   
class [[nodiscard]] run_wrapper
491   
{
521   
{
492   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
522   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
493   
    frame_memory_resource<Alloc> resource_;
523   
    frame_memory_resource<Alloc> resource_;
494   
    Alloc alloc_;  // Copy to pass to awaitable
524   
    Alloc alloc_;  // Copy to pass to awaitable
495  
525  
496   
public:
526   
public:
497   
    explicit run_wrapper(Alloc alloc)
527   
    explicit run_wrapper(Alloc alloc)
498   
        requires InheritStopToken
528   
        requires InheritStopToken
499   
        : resource_(alloc)
529   
        : resource_(alloc)
500   
        , alloc_(std::move(alloc))
530   
        , alloc_(std::move(alloc))
501   
    {
531   
    {
502   
        set_current_frame_allocator(&resource_);
532   
        set_current_frame_allocator(&resource_);
503   
    }
533   
    }
504  
534  
505   
    run_wrapper(std::stop_token st, Alloc alloc)
535   
    run_wrapper(std::stop_token st, Alloc alloc)
506   
        requires (!InheritStopToken)
536   
        requires (!InheritStopToken)
507   
        : st_(std::move(st))
537   
        : st_(std::move(st))
508   
        , resource_(alloc)
538   
        , resource_(alloc)
509   
        , alloc_(std::move(alloc))
539   
        , alloc_(std::move(alloc))
510   
    {
540   
    {
511   
        set_current_frame_allocator(&resource_);
541   
        set_current_frame_allocator(&resource_);
512   
    }
542   
    }
513  
543  
514   
    // Non-copyable, non-movable (must be used immediately)
544   
    // Non-copyable, non-movable (must be used immediately)
515   
    run_wrapper(run_wrapper const&) = delete;
545   
    run_wrapper(run_wrapper const&) = delete;
516   
    run_wrapper(run_wrapper&&) = delete;
546   
    run_wrapper(run_wrapper&&) = delete;
517   
    run_wrapper& operator=(run_wrapper const&) = delete;
547   
    run_wrapper& operator=(run_wrapper const&) = delete;
518   
    run_wrapper& operator=(run_wrapper&&) = delete;
548   
    run_wrapper& operator=(run_wrapper&&) = delete;
519  
549  
520   
    template<IoRunnable Task>
550   
    template<IoRunnable Task>
521   
    [[nodiscard]] auto operator()(Task t) &&
551   
    [[nodiscard]] auto operator()(Task t) &&
522   
    {
552   
    {
523   
        if constexpr (InheritStopToken)
553   
        if constexpr (InheritStopToken)
524   
            return run_awaitable<Task, true, Alloc>{
554   
            return run_awaitable<Task, true, Alloc>{
525   
                std::move(alloc_), std::move(t)};
555   
                std::move(alloc_), std::move(t)};
526   
        else
556   
        else
527   
            return run_awaitable<Task, false, Alloc>{
557   
            return run_awaitable<Task, false, Alloc>{
528   
                std::move(alloc_), std::move(t), std::move(st_)};
558   
                std::move(alloc_), std::move(t), std::move(st_)};
529   
    }
559   
    }
530   
};
560   
};
531  
561  
532   
/// Specialization for memory_resource* - stores pointer directly.
562   
/// Specialization for memory_resource* - stores pointer directly.
533   
template<bool InheritStopToken>
563   
template<bool InheritStopToken>
534   
class [[nodiscard]] run_wrapper<InheritStopToken, std::pmr::memory_resource*>
564   
class [[nodiscard]] run_wrapper<InheritStopToken, std::pmr::memory_resource*>
535   
{
565   
{
536   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
566   
    std::conditional_t<InheritStopToken, std::monostate, std::stop_token> st_;
537   
    std::pmr::memory_resource* mr_;
567   
    std::pmr::memory_resource* mr_;
538  
568  
539   
public:
569   
public:
540   
    explicit run_wrapper(std::pmr::memory_resource* mr)
570   
    explicit run_wrapper(std::pmr::memory_resource* mr)
541   
        requires InheritStopToken
571   
        requires InheritStopToken
542   
        : mr_(mr)
572   
        : mr_(mr)
543   
    {
573   
    {
544   
        set_current_frame_allocator(mr_);
574   
        set_current_frame_allocator(mr_);
545   
    }
575   
    }
546  
576  
547   
    run_wrapper(std::stop_token st, std::pmr::memory_resource* mr)
577   
    run_wrapper(std::stop_token st, std::pmr::memory_resource* mr)
548   
        requires (!InheritStopToken)
578   
        requires (!InheritStopToken)
549   
        : st_(std::move(st))
579   
        : st_(std::move(st))
550   
        , mr_(mr)
580   
        , mr_(mr)
551   
    {
581   
    {
552   
        set_current_frame_allocator(mr_);
582   
        set_current_frame_allocator(mr_);
553   
    }
583   
    }
554  
584  
555   
    // Non-copyable, non-movable (must be used immediately)
585   
    // Non-copyable, non-movable (must be used immediately)
556   
    run_wrapper(run_wrapper const&) = delete;
586   
    run_wrapper(run_wrapper const&) = delete;
557   
    run_wrapper(run_wrapper&&) = delete;
587   
    run_wrapper(run_wrapper&&) = delete;
558   
    run_wrapper& operator=(run_wrapper const&) = delete;
588   
    run_wrapper& operator=(run_wrapper const&) = delete;
559   
    run_wrapper& operator=(run_wrapper&&) = delete;
589   
    run_wrapper& operator=(run_wrapper&&) = delete;
560  
590  
561   
    template<IoRunnable Task>
591   
    template<IoRunnable Task>
562   
    [[nodiscard]] auto operator()(Task t) &&
592   
    [[nodiscard]] auto operator()(Task t) &&
563   
    {
593   
    {
564   
        if constexpr (InheritStopToken)
594   
        if constexpr (InheritStopToken)
565   
            return run_awaitable<Task, true, std::pmr::memory_resource*>{
595   
            return run_awaitable<Task, true, std::pmr::memory_resource*>{
566   
                mr_, std::move(t)};
596   
                mr_, std::move(t)};
567   
        else
597   
        else
568   
            return run_awaitable<Task, false, std::pmr::memory_resource*>{
598   
            return run_awaitable<Task, false, std::pmr::memory_resource*>{
569   
                mr_, std::move(t), std::move(st_)};
599   
                mr_, std::move(t), std::move(st_)};
570   
    }
600   
    }
571   
};
601   
};
572  
602  
573   
/// Specialization for stop_token only (no allocator).
603   
/// Specialization for stop_token only (no allocator).
574   
template<>
604   
template<>
575   
class [[nodiscard]] run_wrapper<false, void>
605   
class [[nodiscard]] run_wrapper<false, void>
576   
{
606   
{
577   
    std::stop_token st_;
607   
    std::stop_token st_;
578  
608  
579   
public:
609   
public:
580   
    explicit run_wrapper(std::stop_token st)
610   
    explicit run_wrapper(std::stop_token st)
581   
        : st_(std::move(st))
611   
        : st_(std::move(st))
582   
    {
612   
    {
583   
    }
613   
    }
584  
614  
585   
    // Non-copyable, non-movable (must be used immediately)
615   
    // Non-copyable, non-movable (must be used immediately)
586   
    run_wrapper(run_wrapper const&) = delete;
616   
    run_wrapper(run_wrapper const&) = delete;
587   
    run_wrapper(run_wrapper&&) = delete;
617   
    run_wrapper(run_wrapper&&) = delete;
588   
    run_wrapper& operator=(run_wrapper const&) = delete;
618   
    run_wrapper& operator=(run_wrapper const&) = delete;
589   
    run_wrapper& operator=(run_wrapper&&) = delete;
619   
    run_wrapper& operator=(run_wrapper&&) = delete;
590  
620  
591   
    template<IoRunnable Task>
621   
    template<IoRunnable Task>
592   
    [[nodiscard]] auto operator()(Task t) &&
622   
    [[nodiscard]] auto operator()(Task t) &&
593   
    {
623   
    {
594   
        return run_awaitable<Task, false, void>{std::move(t), std::move(st_)};
624   
        return run_awaitable<Task, false, void>{std::move(t), std::move(st_)};
595   
    }
625   
    }
596   
};
626   
};
597  
627  
598   
} // namespace boost::capy::detail
628   
} // namespace boost::capy::detail
599  
629  
600   
namespace boost::capy {
630   
namespace boost::capy {
601  
631  
 
632 + 
//----------------------------------------------------------
 
633 + 
//
 
634 + 
// run() overloads - with executor
 
635 + 
//
 
636 + 
//----------------------------------------------------------
 
637 +
602   
/** Bind a task to execute on a specific executor.
638   
/** Bind a task to execute on a specific executor.
603  
639  
604   
    Returns a wrapper that accepts a task and produces an awaitable.
640   
    Returns a wrapper that accepts a task and produces an awaitable.
605   
    When co_awaited, the task runs on the specified executor.
641   
    When co_awaited, the task runs on the specified executor.
606  
642  
607   
    @par Example
643   
    @par Example
608   
    @code
644   
    @code
609   
    co_await run(other_executor)(my_task());
645   
    co_await run(other_executor)(my_task());
610   
    @endcode
646   
    @endcode
611  
647  
612   
    @param ex The executor on which the task should run.
648   
    @param ex The executor on which the task should run.
613  
649  
614   
    @return A wrapper that accepts a task for execution.
650   
    @return A wrapper that accepts a task for execution.
615  
651  
616   
    @see task
652   
    @see task
617   
    @see executor
653   
    @see executor
618   
*/
654   
*/
619   
template<Executor Ex>
655   
template<Executor Ex>
620   
[[nodiscard]] auto
656   
[[nodiscard]] auto
621   
run(Ex ex)
657   
run(Ex ex)
622   
{
658   
{
623   
    return detail::run_wrapper_ex<Ex, true, void>{std::move(ex)};
659   
    return detail::run_wrapper_ex<Ex, true, void>{std::move(ex)};
624   
}
660   
}
625  
661  
626   
/** Bind a task to an executor with a stop token.
662   
/** Bind a task to an executor with a stop token.
627  
663  
628   
    @param ex The executor on which the task should run.
664   
    @param ex The executor on which the task should run.
629   
    @param st The stop token for cooperative cancellation.
665   
    @param st The stop token for cooperative cancellation.
630  
666  
631   
    @return A wrapper that accepts a task for execution.
667   
    @return A wrapper that accepts a task for execution.
632   
*/
668   
*/
633   
template<Executor Ex>
669   
template<Executor Ex>
634   
[[nodiscard]] auto
670   
[[nodiscard]] auto
635   
run(Ex ex, std::stop_token st)
671   
run(Ex ex, std::stop_token st)
636   
{
672   
{
637   
    return detail::run_wrapper_ex<Ex, false, void>{
673   
    return detail::run_wrapper_ex<Ex, false, void>{
638   
        std::move(ex), std::move(st)};
674   
        std::move(ex), std::move(st)};
639   
}
675   
}
640  
676  
641   
/** Bind a task to an executor with a memory resource.
677   
/** Bind a task to an executor with a memory resource.
642  
678  
643   
    @param ex The executor on which the task should run.
679   
    @param ex The executor on which the task should run.
644   
    @param mr The memory resource for frame allocation.
680   
    @param mr The memory resource for frame allocation.
645  
681  
646   
    @return A wrapper that accepts a task for execution.
682   
    @return A wrapper that accepts a task for execution.
647   
*/
683   
*/
648   
template<Executor Ex>
684   
template<Executor Ex>
649   
[[nodiscard]] auto
685   
[[nodiscard]] auto
650   
run(Ex ex, std::pmr::memory_resource* mr)
686   
run(Ex ex, std::pmr::memory_resource* mr)
651   
{
687   
{
652   
    return detail::run_wrapper_ex<Ex, true, std::pmr::memory_resource*>{
688   
    return detail::run_wrapper_ex<Ex, true, std::pmr::memory_resource*>{
653   
        std::move(ex), mr};
689   
        std::move(ex), mr};
654   
}
690   
}
655  
691  
656   
/** Bind a task to an executor with a standard allocator.
692   
/** Bind a task to an executor with a standard allocator.
657  
693  
658   
    @param ex The executor on which the task should run.
694   
    @param ex The executor on which the task should run.
659   
    @param alloc The allocator for frame allocation.
695   
    @param alloc The allocator for frame allocation.
660  
696  
661   
    @return A wrapper that accepts a task for execution.
697   
    @return A wrapper that accepts a task for execution.
662   
*/
698   
*/
663   
template<Executor Ex, detail::Allocator Alloc>
699   
template<Executor Ex, detail::Allocator Alloc>
664   
[[nodiscard]] auto
700   
[[nodiscard]] auto
665   
run(Ex ex, Alloc alloc)
701   
run(Ex ex, Alloc alloc)
666   
{
702   
{
667   
    return detail::run_wrapper_ex<Ex, true, Alloc>{
703   
    return detail::run_wrapper_ex<Ex, true, Alloc>{
668   
        std::move(ex), std::move(alloc)};
704   
        std::move(ex), std::move(alloc)};
669   
}
705   
}
670  
706  
671   
/** Bind a task to an executor with stop token and memory resource.
707   
/** Bind a task to an executor with stop token and memory resource.
672  
708  
673   
    @param ex The executor on which the task should run.
709   
    @param ex The executor on which the task should run.
674   
    @param st The stop token for cooperative cancellation.
710   
    @param st The stop token for cooperative cancellation.
675   
    @param mr The memory resource for frame allocation.
711   
    @param mr The memory resource for frame allocation.
676  
712  
677   
    @return A wrapper that accepts a task for execution.
713   
    @return A wrapper that accepts a task for execution.
678   
*/
714   
*/
679   
template<Executor Ex>
715   
template<Executor Ex>
680   
[[nodiscard]] auto
716   
[[nodiscard]] auto
681   
run(Ex ex, std::stop_token st, std::pmr::memory_resource* mr)
717   
run(Ex ex, std::stop_token st, std::pmr::memory_resource* mr)
682   
{
718   
{
683   
    return detail::run_wrapper_ex<Ex, false, std::pmr::memory_resource*>{
719   
    return detail::run_wrapper_ex<Ex, false, std::pmr::memory_resource*>{
684   
        std::move(ex), std::move(st), mr};
720   
        std::move(ex), std::move(st), mr};
685   
}
721   
}
686  
722  
687   
/** Bind a task to an executor with stop token and standard allocator.
723   
/** Bind a task to an executor with stop token and standard allocator.
688  
724  
689   
    @param ex The executor on which the task should run.
725   
    @param ex The executor on which the task should run.
690   
    @param st The stop token for cooperative cancellation.
726   
    @param st The stop token for cooperative cancellation.
691   
    @param alloc The allocator for frame allocation.
727   
    @param alloc The allocator for frame allocation.
692  
728  
693   
    @return A wrapper that accepts a task for execution.
729   
    @return A wrapper that accepts a task for execution.
694   
*/
730   
*/
695   
template<Executor Ex, detail::Allocator Alloc>
731   
template<Executor Ex, detail::Allocator Alloc>
696   
[[nodiscard]] auto
732   
[[nodiscard]] auto
697   
run(Ex ex, std::stop_token st, Alloc alloc)
733   
run(Ex ex, std::stop_token st, Alloc alloc)
698   
{
734   
{
699   
    return detail::run_wrapper_ex<Ex, false, Alloc>{
735   
    return detail::run_wrapper_ex<Ex, false, Alloc>{
700   
        std::move(ex), std::move(st), std::move(alloc)};
736   
        std::move(ex), std::move(st), std::move(alloc)};
701   
}
737   
}
 
738 +
 
739 + 
//----------------------------------------------------------
 
740 + 
//
 
741 + 
// run() overloads - no executor (inherits caller's)
 
742 + 
//
 
743 + 
//----------------------------------------------------------
702  
744  
703   
/** Run a task with a custom stop token.
745   
/** Run a task with a custom stop token.
704  
746  
705   
    The task inherits the caller's executor. Only the stop token
747   
    The task inherits the caller's executor. Only the stop token
706   
    is overridden.
748   
    is overridden.
707  
749  
708   
    @par Example
750   
    @par Example
709   
    @code
751   
    @code
710   
    std::stop_source source;
752   
    std::stop_source source;
711   
    co_await run(source.get_token())(cancellable_task());
753   
    co_await run(source.get_token())(cancellable_task());
712   
    @endcode
754   
    @endcode
713  
755  
714   
    @param st The stop token for cooperative cancellation.
756   
    @param st The stop token for cooperative cancellation.
715  
757  
716   
    @return A wrapper that accepts a task for execution.
758   
    @return A wrapper that accepts a task for execution.
717   
*/
759   
*/
718   
[[nodiscard]] inline auto
760   
[[nodiscard]] inline auto
719   
run(std::stop_token st)
761   
run(std::stop_token st)
720   
{
762   
{
721   
    return detail::run_wrapper<false, void>{std::move(st)};
763   
    return detail::run_wrapper<false, void>{std::move(st)};
722   
}
764   
}
723  
765  
724   
/** Run a task with a custom memory resource.
766   
/** Run a task with a custom memory resource.
725  
767  
726   
    The task inherits the caller's executor. The memory resource
768   
    The task inherits the caller's executor. The memory resource
727   
    is used for nested frame allocations.
769   
    is used for nested frame allocations.
728  
770  
729   
    @param mr The memory resource for frame allocation.
771   
    @param mr The memory resource for frame allocation.
730  
772  
731   
    @return A wrapper that accepts a task for execution.
773   
    @return A wrapper that accepts a task for execution.
732   
*/
774   
*/
733   
[[nodiscard]] inline auto
775   
[[nodiscard]] inline auto
734   
run(std::pmr::memory_resource* mr)
776   
run(std::pmr::memory_resource* mr)
735   
{
777   
{
736   
    return detail::run_wrapper<true, std::pmr::memory_resource*>{mr};
778   
    return detail::run_wrapper<true, std::pmr::memory_resource*>{mr};
737   
}
779   
}
738  
780  
739   
/** Run a task with a custom standard allocator.
781   
/** Run a task with a custom standard allocator.
740  
782  
741   
    The task inherits the caller's executor. The allocator is used
783   
    The task inherits the caller's executor. The allocator is used
742   
    for nested frame allocations.
784   
    for nested frame allocations.
743  
785  
744   
    @param alloc The allocator for frame allocation.
786   
    @param alloc The allocator for frame allocation.
745  
787  
746   
    @return A wrapper that accepts a task for execution.
788   
    @return A wrapper that accepts a task for execution.
747   
*/
789   
*/
748   
template<detail::Allocator Alloc>
790   
template<detail::Allocator Alloc>
749   
[[nodiscard]] auto
791   
[[nodiscard]] auto
750   
run(Alloc alloc)
792   
run(Alloc alloc)
751   
{
793   
{
752   
    return detail::run_wrapper<true, Alloc>{std::move(alloc)};
794   
    return detail::run_wrapper<true, Alloc>{std::move(alloc)};
753   
}
795   
}
754  
796  
755   
/** Run a task with stop token and memory resource.
797   
/** Run a task with stop token and memory resource.
756  
798  
757   
    The task inherits the caller's executor.
799   
    The task inherits the caller's executor.
758  
800  
759   
    @param st The stop token for cooperative cancellation.
801   
    @param st The stop token for cooperative cancellation.
760   
    @param mr The memory resource for frame allocation.
802   
    @param mr The memory resource for frame allocation.
761  
803  
762   
    @return A wrapper that accepts a task for execution.
804   
    @return A wrapper that accepts a task for execution.
763   
*/
805   
*/
764   
[[nodiscard]] inline auto
806   
[[nodiscard]] inline auto
765   
run(std::stop_token st, std::pmr::memory_resource* mr)
807   
run(std::stop_token st, std::pmr::memory_resource* mr)
766   
{
808   
{
767   
    return detail::run_wrapper<false, std::pmr::memory_resource*>{
809   
    return detail::run_wrapper<false, std::pmr::memory_resource*>{
768   
        std::move(st), mr};
810   
        std::move(st), mr};
769   
}
811   
}
770  
812  
771   
/** Run a task with stop token and standard allocator.
813   
/** Run a task with stop token and standard allocator.
772  
814  
773   
    The task inherits the caller's executor.
815   
    The task inherits the caller's executor.
774  
816  
775   
    @param st The stop token for cooperative cancellation.
817   
    @param st The stop token for cooperative cancellation.
776   
    @param alloc The allocator for frame allocation.
818   
    @param alloc The allocator for frame allocation.
777  
819  
778   
    @return A wrapper that accepts a task for execution.
820   
    @return A wrapper that accepts a task for execution.
779   
*/
821   
*/
780   
template<detail::Allocator Alloc>
822   
template<detail::Allocator Alloc>
781   
[[nodiscard]] auto
823   
[[nodiscard]] auto
782   
run(std::stop_token st, Alloc alloc)
824   
run(std::stop_token st, Alloc alloc)
783   
{
825   
{
784   
    return detail::run_wrapper<false, Alloc>{
826   
    return detail::run_wrapper<false, Alloc>{
785   
        std::move(st), std::move(alloc)};
827   
        std::move(st), std::move(alloc)};
786   
}
828   
}
787  
829  
788   
} // namespace boost::capy
830   
} // namespace boost::capy
789  
831  
790   
#endif
832   
#endif