Adds support for signal handlers, asynchonous events, and callbacks injected from other threads to the basic functionality in pollset_light.
More...
#include <pollset.h>
Public Member Functions | |
| bool | pending () const override |
Returns false if no file descriptor callbacks are registered and no timeouts or asynchronous events are pending. More... | |
| void | wake () |
| Cause PollSet::poll to return if it is sleeping. More... | |
| template<typename CB > | |
| void | inject_cb (CB &&cb) |
| Inject a callback to run immediately. More... | |
| template<typename Work , typename CB > | |
| void | async (Work &&work, CB &&cb) |
| Execute a task asynchonously in another thread, then run callback on the task's result in the main thread. More... | |
| void | signal_cb (int sig, cb_t cb) |
| Add a callback for a particular signal. More... | |
 Public Member Functions inherited from xdr::pollset | |
| pollset (const pollset &)=delete | |
| void | poll (int timeout=-1) |
| Go through one round of checking all file descriptors. More... | |
| void | run () |
| Continously poll and only return on exception or when there is no more work to do. More... | |
| template<typename CB > | |
| void | fd_cb (sock_t s, op_t op, CB &&cb) |
| Set a read or write callback on a particular file descriptor. More... | |
| void | fd_cb (sock_t s, op_t op, std::nullptr_t=nullptr) |
| Remove a callback on a file descriptor. More... | |
| template<typename CB > | |
| Timeout | timeout (std::int64_t ms, CB &&cb) |
| Set a callback to run a certain number of milliseconds from now. More... | |
| template<typename CB > | |
| Timeout | timeout_at (std::int64_t ms, CB &&cb) |
| Set a callback to run at a specific time (as returned by PollSet::now_ms()). More... | |
| void | timeout_cancel (Timeout &t) |
| Cancel a pending timeout. More... | |
| std::int64_t | timeout_time (Timeout t) const |
| Returns the absolute time (in milliseconds) at which a timeout will run. More... | |
| void | timeout_reschedule_at (Timeout &t, std::int64_t ms) |
| Reschedule a timeout to run at a specific time. More... | |
| void | timeout_reschedule (Timeout &t, std::int64_t ms) |
| Reschedule a timeout some number of milliseconds in the future. | |
Static Public Member Functions | |
| static void | signal_cb (int sig, std::nullptr_t=nullptr) |
| Remove any previously added callback for a particular signal. More... | |
| Static Public Member Functions inherited from xdr::pollset | |
| static std::int64_t | now_ms () |
| Number of milliseconds since an arbitrary but fixed time, used as the basis of all timeouts. More... | |
| static Timeout | timeout_null () |
| An invalid timeout, useful for initializing PollSet::Timeout values before a timeout has been scheduled. More... | |
Additional Inherited Members | |
| Public Types inherited from xdr::pollset | |
| enum | op_t { Read = kReadFlag, Write = kWriteFlag, ReadWrite = kReadFlag | kWriteFlag, ReadOnce = kReadFlag | kOnceFlag, WriteOnce = kWriteFlag | kOnceFlag } |
| using | cb_t = std::function< void()> |
| Protected Member Functions inherited from xdr::pollset | |
| std::size_t | num_cbs () const |
| Number of registered file decriptor and timeout callbacks. | |
| Static Protected Attributes inherited from xdr::pollset | |
| static constexpr int | kReadFlag = 0x1 |
| static constexpr int | kWriteFlag = 0x2 |
| static constexpr int | kOnceFlag = 0x4 |
Detailed Description
Adds support for signal handlers, asynchonous events, and callbacks injected from other threads to the basic functionality in pollset_light.
Member Function Documentation
◆ pending()
|
overridevirtual |
Returns false if no file descriptor callbacks are registered and no timeouts or asynchronous events are pending.
If it returns false, then PollSet::poll will pause forever in the absence of a signal or a call to PollSet::inject_cb in a different thread.
Reimplemented from xdr::pollset.
Definition at line 194 of file pollset.cc.
◆ wake()
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inline |
◆ inject_cb()
|
inline |
Inject a callback to run immediately.
Unlike most methods, it is safe to call this function from another thread. Being thread-safe adds extra overhead, so it does not make sense to call this function from the same thread as PollSet::poll. Note that inject_cb acquires a lock and definitely must not be called from a signal handler (or deadlock could ensue).
◆ async()
|
inline |
Execute a task asynchonously in another thread, then run callback on the task's result in the main thread.
workis a task to perform asynchronously in another thread, and must be convertible to std::function<R()> for some typeR.cbis the callback that processes the result in the main thread, and must be convertible to std::function<void(R)> for the same typeR.
◆ signal_cb() [1/2]
| void xdr::pollset_plus::signal_cb | ( | int | sig, |
| cb_t | cb | ||
| ) |
Add a callback for a particular signal.
Note that only one callback can be added for a particular signal across all pollset_plus instances in a single process. Hence, calling this function may "steal" a signal from a different pollset_plus (erasing whatever callback the other pollset_plus had for the signal). Such callback stealing is atomic, allowing one to steal a pollset_plus's signals before deleting it with no risk of signals going uncaught.
Definition at line 340 of file pollset.cc.
◆ signal_cb() [2/2]
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static |
Remove any previously added callback for a particular signal.
Because signal callbacks are process-wide, this static method will affect whatever pollset_plus currently owns the signal.
Definition at line 401 of file pollset.cc.
The documentation for this class was generated from the following files:
- xdrpp/pollset.h
- xdrpp/pollset.cc
