Name
SPVM::IO::Poll - poll system call
Description
IO::Poll class in SPVM has methods for poll system call.
Usage
use IO::Poll;
use Sys::Poll::Constant as POLL;
my $poll = IO::Poll->new;
$poll->set_mask($input_fd => POLL->POLLIN);
$poll->set_mask($output_fd => POLL->POLLOUT);
$poll->poll($timeout);
my $events = $poll->events($input_fd);Details
Porting
This class is a Perl's IO::Poll porting to SPVM.
Fields
pollfd_array
has pollfd_array : Sys::Poll::PollfdArray;
A Sys::Poll::PollfdArray object.
fd_indexes_h
has fd_indexes_h : Hash of Int;
A hash whose keys are file descriptors and whose values are indexes of "pollfd_array".
disabled_fd_indexes
has disabled_fd_indexes : IntList;
A list of indexes of disabled file descriptors of "pollfd_array".
Class Methods
new
static method new : IO::Poll ();
Creates a new IO::Poll object and returns it.
Implementation:
A Sys::Poll::PollfdArray object is created and sets "pollfd_array" field to it.
A Hash object is created and sets "fd_indexes_h" field to it.
An IntList object is created and sets "disabled_fd_indexes" field to it.
Instance Methods
fds
method fds : int[] ();
Returns file descriptors.
Implementation:
Returned file descriptors are non-negative file descriptors in "pollfd_array".
mask
method mask : int ($fd : int);
Returns the current event mask for the file descriptor $fd.
If $fd is not found, returns 0.
Exceptions:
The file descriptor $fd must be greater than or equal to 0. Otherwise, an exception is thrown.
set_mask
method set_mask : void ($fd : int, $event_mask : int);
If the event mask $event_mask is not 0, adds the file descriptor $fd.
If $event_mask is 0, removes the file descriptor $fd.
Implementation:
This method with $event_mask 0 is not remove a file descriptor from "pollfd_array". It sets the file descriptor to -1 that means disabled.
poll system call ignores file descriptors that have a negative value.
This method with $fd and $event_mask non-zero set a disabled file descriptor to $fd if there are disabled file descriptors.
With this impelmenetaion, the computational complexity of addition and removal of this method is O(1).
Exceptions:
The file descriptor $fd must be greater than or equal to 0. Otherwise, an exception is thrown.
remove
method remove : void ($fd : int);
Removes the file descriptor $fd.
This method is the same as the following code using "set_mask" method.
$poll->set_mask($fd, 0);poll
method poll : int ($timeout : double = -1);
Calls poll system call given the timeout seconds $timeout.
If $timeout is a negative value, the call blocks.
Returns the number of file descriptors which had events happen.
This method calls Sys::Poll#poll method.
Exceptions:
Excetpions thrown by Sys::Poll#poll method could be thrown.
events
method events : int ($fd : int);
Returns the event mask which represents the events that happened on the file descriptor $fd during the last "poll" method call.
See Also
Copyright & License
Copyright (c) 2024 Yuki Kimoto
MIT License