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