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Update documentation for dispatch, post, and defer.

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This commit is contained in:
Christopher Kohlhoff
2022-03-04 20:56:01 +11:00
parent 8e69bf3cf3
commit d35b87ff27
12 changed files with 917 additions and 293 deletions
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129
include/boost/asio/defer.hpp
View File

@@ -38,30 +38,48 @@ namespace asio {
* may allow the executor to optimise queueing for cases when the function
* object represents a continuation of the current call context.
*
* This function has the following effects:
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{}, token)</tt>, where @c Init is a function object type defined
* as:
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @code class Init
* {
* public:
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* }; @endcode
*
* @li Obtains the handler's associated executor object @c ex by performing
* <tt>get_associated_executor(handler)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex of type @c Ex by
* performing @code auto ex = get_associated_executor(handler); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Performs <tt>ex.defer(std::move(handler), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(
* require(ex, execution::blocking.never),
* execution::relationship.continuation,
* execution::allocator(alloc)),
* std::forward<CompletionHandler>(completion_handler)); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.defer(
* std::forward<CompletionHandler>(completion_handler),
* alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
BOOST_ASIO_MOVE_ARG(CompletionToken) token);
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
BOOST_ASIO_MOVE_ARG(NullaryToken) token);
/// Submits a completion token or function object for execution.
/**
@@ -74,39 +92,76 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
* may allow the executor to optimise queueing for cases when the function
* object represents a continuation of the current call context.
*
* This function has the following effects:
* @param ex The target executor.
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{ex}, token)</tt>, where @c Init is a function object type
* defined as:
*
* @li Obtains the handler's associated executor object @c ex1 by performing
* <tt>get_associated_executor(handler)</tt>.
* @code class Init
* {
* public:
* using executor_type = Executor;
* explicit Init(const Executor& ex) : ex_(ex) {}
* executor_type get_executor() const noexcept { return ex_; }
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* private:
* Executor ex_; // exposition only
* }; @endcode
*
* @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex1 of type @c Ex1 by
* performing @code auto ex1 = get_associated_executor(handler, ex); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Constructs a function object @c f with a function call operator that
* performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
* <tt>w.reset()</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is true, constructs a
* function object @c f with a member @c executor_ that is initialised with
* <tt>prefer(ex1, execution::outstanding_work.tracked)</tt>, a member @c
* handler_ that is a decay-copy of @c completion_handler, and a function call
* operator that performs:
* @code auto a = get_associated_allocator(handler_);
* execution::execute(
* prefer(executor_,
* execution::blocking.possibly,
* execution::allocator(a)),
* std::move(handler_)); @endcode
*
* @li Performs <tt>Executor(ex).defer(std::move(f), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is false, constructs a
* function object @c f with a member @c work_ that is initialised with
* <tt>make_work_guard(ex1)</tt>, a member @c handler_ that is a decay-copy of
* @c completion_handler, and a function call operator that performs:
* @code auto a = get_associated_allocator(handler_);
* work_.get_executor().dispatch(std::move(handler_), a);
* work_.reset(); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(
* require(ex, execution::blocking.never),
* execution::relationship.continuation,
* execution::allocator(alloc)),
* std::move(f)); @endcode
*
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.defer(std::move(f), alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
const Executor& ex,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
@@ -114,18 +169,24 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
/// Submits a completion token or function object for execution.
/**
* @returns <tt>defer(ctx.get_executor(), forward<CompletionToken>(token))</tt>.
* @param ctx An execution context, from which the target executor is obtained.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @returns <tt>defer(ctx.get_executor(), forward<NullaryToken>(token))</tt>.
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
ExecutionContext& ctx,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<is_convertible<

127
include/boost/asio/dispatch.hpp
View File

@@ -33,30 +33,47 @@ namespace asio {
* executor. The function object may be called from the current thread prior to
* returning from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
*
* This function has the following effects:
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{}, token)</tt>, where @c Init is a function object type defined
* as:
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @code class Init
* {
* public:
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* }; @endcode
*
* @li Obtains the handler's associated executor object @c ex by performing
* <tt>get_associated_executor(handler)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex of type @c Ex by
* performing @code auto ex = get_associated_executor(handler); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Performs <tt>ex.dispatch(std::move(handler), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(ex,
* execution::blocking.possibly,
* execution::allocator(alloc)),
* std::forward<CompletionHandler>(completion_handler)); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.dispatch(
* std::forward<CompletionHandler>(completion_handler),
* alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
BOOST_ASIO_MOVE_ARG(CompletionToken) token);
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
BOOST_ASIO_MOVE_ARG(NullaryToken) token);
/// Submits a completion token or function object for execution.
/**
@@ -64,39 +81,75 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
* The function object may be called from the current thread prior to returning
* from <tt>dispatch()</tt>. Otherwise, it is queued for execution.
*
* This function has the following effects:
* @param ex The target executor.
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{ex}, token)</tt>, where @c Init is a function object type
* defined as:
*
* @li Obtains the handler's associated executor object @c ex1 by performing
* <tt>get_associated_executor(handler)</tt>.
* @code class Init
* {
* public:
* using executor_type = Executor;
* explicit Init(const Executor& ex) : ex_(ex) {}
* executor_type get_executor() const noexcept { return ex_; }
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* private:
* Executor ex_; // exposition only
* }; @endcode
*
* @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex1 of type @c Ex1 by
* performing @code auto ex1 = get_associated_executor(handler, ex); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Constructs a function object @c f with a function call operator that
* performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
* <tt>w.reset()</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is true, constructs a
* function object @c f with a member @c executor_ that is initialised with
* <tt>prefer(ex1, execution::outstanding_work.tracked)</tt>, a member @c
* handler_ that is a decay-copy of @c completion_handler, and a function call
* operator that performs:
* @code auto a = get_associated_allocator(handler_);
* execution::execute(
* prefer(executor_,
* execution::blocking.possibly,
* execution::allocator(a)),
* std::move(handler_)); @endcode
*
* @li Performs <tt>Executor(ex).dispatch(std::move(f), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is false, constructs a
* function object @c f with a member @c work_ that is initialised with
* <tt>make_work_guard(ex1)</tt>, a member @c handler_ that is a decay-copy of
* @c completion_handler, and a function call operator that performs:
* @code auto a = get_associated_allocator(handler_);
* work_.get_executor().dispatch(std::move(handler_), a);
* work_.reset(); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(ex,
* execution::blocking.possibly,
* execution::allocator(alloc)),
* std::move(f)); @endcode
*
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.dispatch(std::move(f), alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
const Executor& ex,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
@@ -104,19 +157,25 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
/// Submits a completion token or function object for execution.
/**
* @param ctx An execution context, from which the target executor is obtained.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @returns <tt>dispatch(ctx.get_executor(),
* forward<CompletionToken>(token))</tt>.
* forward<NullaryToken>(token))</tt>.
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
ExecutionContext& ctx,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<is_convertible<

24
include/boost/asio/impl/defer.hpp
View File

@@ -217,34 +217,34 @@ private:
} // namespace detail
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
BOOST_ASIO_MOVE_ARG(CompletionToken) token)
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
BOOST_ASIO_MOVE_ARG(NullaryToken) token)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_defer(), token);
}
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
const Executor& ex, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
const Executor& ex, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_defer_with_executor<Executor>(ex), token);
}
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) defer(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) defer(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<is_convertible<
ExecutionContext&, execution_context&>::value>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_defer_with_executor<
typename ExecutionContext::executor_type>(
ctx.get_executor()), token);

24
include/boost/asio/impl/dispatch.hpp
View File

@@ -212,34 +212,34 @@ private:
} // namespace detail
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
BOOST_ASIO_MOVE_ARG(CompletionToken) token)
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
BOOST_ASIO_MOVE_ARG(NullaryToken) token)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_dispatch(), token);
}
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
const Executor& ex, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
const Executor& ex, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_dispatch_with_executor<Executor>(ex), token);
}
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) dispatch(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) dispatch(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<is_convertible<
ExecutionContext&, execution_context&>::value>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_dispatch_with_executor<
typename ExecutionContext::executor_type>(
ctx.get_executor()), token);

24
include/boost/asio/impl/post.hpp
View File

@@ -217,34 +217,34 @@ private:
} // namespace detail
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
BOOST_ASIO_MOVE_ARG(CompletionToken) token)
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
BOOST_ASIO_MOVE_ARG(NullaryToken) token)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_post(), token);
}
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
const Executor& ex, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
const Executor& ex, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_post_with_executor<Executor>(ex), token);
}
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(CompletionToken) token,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
inline BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
ExecutionContext& ctx, BOOST_ASIO_MOVE_ARG(NullaryToken) token,
typename constraint<is_convertible<
ExecutionContext&, execution_context&>::value>::type)
{
return async_initiate<CompletionToken, void()>(
return async_initiate<NullaryToken, void()>(
detail::initiate_post_with_executor<
typename ExecutionContext::executor_type>(
ctx.get_executor()), token);

129
include/boost/asio/post.hpp
View File

@@ -36,30 +36,48 @@ namespace asio {
* The use of @c post(), rather than @ref defer(), indicates the caller's
* preference that the function object be eagerly queued for execution.
*
* This function has the following effects:
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{}, token)</tt>, where @c Init is a function object type defined
* as:
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @code class Init
* {
* public:
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* }; @endcode
*
* @li Obtains the handler's associated executor object @c ex by performing
* <tt>get_associated_executor(handler)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex of type @c Ex by
* performing @code auto ex = get_associated_executor(handler); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Performs <tt>ex.post(std::move(handler), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(
* require(ex, execution::blocking.never),
* execution::relationship.fork,
* execution::allocator(alloc)),
* std::forward<CompletionHandler>(completion_handler)); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.post(
* std::forward<CompletionHandler>(completion_handler),
* alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
BOOST_ASIO_MOVE_ARG(CompletionToken) token);
template <BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
BOOST_ASIO_MOVE_ARG(NullaryToken) token);
/// Submits a completion token or function object for execution.
/**
@@ -70,39 +88,76 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
* The use of @c post(), rather than @ref defer(), indicates the caller's
* preference that the function object be eagerly queued for execution.
*
* This function has the following effects:
* @param ex The target executor.
*
* @li Constructs a function object handler of type @c Handler, initialized
* with <tt>handler(forward<CompletionToken>(token))</tt>.
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @li Constructs an object @c result of type <tt>async_result<Handler></tt>,
* initializing the object as <tt>result(handler)</tt>.
* @returns This function returns <tt>async_initiate<NullaryToken,
* void()>(Init{ex}, token)</tt>, where @c Init is a function object type
* defined as:
*
* @li Obtains the handler's associated executor object @c ex1 by performing
* <tt>get_associated_executor(handler)</tt>.
* @code class Init
* {
* public:
* using executor_type = Executor;
* explicit Init(const Executor& ex) : ex_(ex) {}
* executor_type get_executor() const noexcept { return ex_; }
* template <typename CompletionHandler>
* void operator()(CompletionHandler&& completion_handler) const;
* private:
* Executor ex_; // exposition only
* }; @endcode
*
* @li Creates a work object @c w by performing <tt>make_work(ex1)</tt>.
* The function call operator of @c Init:
*
* @li Obtains the handler's associated executor object @c ex1 of type @c Ex1 by
* performing @code auto ex1 = get_associated_executor(handler, ex); @endcode
*
* @li Obtains the handler's associated allocator object @c alloc by performing
* <tt>get_associated_allocator(handler)</tt>.
* @code auto alloc = get_associated_allocator(handler); @endcode
*
* @li Constructs a function object @c f with a function call operator that
* performs <tt>ex1.dispatch(std::move(handler), alloc)</tt> followed by
* <tt>w.reset()</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is true, constructs a
* function object @c f with a member @c executor_ that is initialised with
* <tt>prefer(ex1, execution::outstanding_work.tracked)</tt>, a member @c
* handler_ that is a decay-copy of @c completion_handler, and a function call
* operator that performs:
* @code auto a = get_associated_allocator(handler_);
* execution::execute(
* prefer(executor_,
* execution::blocking.possibly,
* execution::allocator(a)),
* std::move(handler_)); @endcode
*
* @li Performs <tt>Executor(ex).post(std::move(f), alloc)</tt>.
* @li If <tt>execution::is_executor<Ex1>::value</tt> is false, constructs a
* function object @c f with a member @c work_ that is initialised with
* <tt>make_work_guard(ex1)</tt>, a member @c handler_ that is a decay-copy of
* @c completion_handler, and a function call operator that performs:
* @code auto a = get_associated_allocator(handler_);
* work_.get_executor().dispatch(std::move(handler_), a);
* work_.reset(); @endcode
*
* @li Returns <tt>result.get()</tt>.
* @li If <tt>execution::is_executor<Ex>::value</tt> is true, performs
* @code execution::execute(
* prefer(
* require(ex, execution::blocking.never),
* execution::relationship.fork,
* execution::allocator(alloc)),
* std::move(f)); @endcode
*
* @li If <tt>execution::is_executor<Ex>::value</tt> is false, performs
* @code ex.post(std::move(f), alloc); @endcode
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename Executor,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(Executor)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
const Executor& ex,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(Executor),
typename constraint<
execution::is_executor<Executor>::value || is_executor<Executor>::value
@@ -110,18 +165,24 @@ BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
/// Submits a completion token or function object for execution.
/**
* @returns <tt>post(ctx.get_executor(), forward<CompletionToken>(token))</tt>.
* @param ctx An execution context, from which the target executor is obtained.
*
* @param token The @ref completion_token that will be used to produce a
* completion handler. The function signature of the completion handler must be:
* @code void handler(); @endcode
*
* @returns <tt>post(ctx.get_executor(), forward<NullaryToken>(token))</tt>.
*
* @par Completion Signature
* @code void() @endcode
*/
template <typename ExecutionContext,
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) CompletionToken
BOOST_ASIO_COMPLETION_TOKEN_FOR(void()) NullaryToken
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN_TYPE(
typename ExecutionContext::executor_type)>
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(CompletionToken, void()) post(
BOOST_ASIO_INITFN_AUTO_RESULT_TYPE(NullaryToken, void()) post(
ExecutionContext& ctx,
BOOST_ASIO_MOVE_ARG(CompletionToken) token
BOOST_ASIO_MOVE_ARG(NullaryToken) token
BOOST_ASIO_DEFAULT_COMPLETION_TOKEN(
typename ExecutionContext::executor_type),
typename constraint<is_convertible<