Commit | Line | Data |
9e72f0cf |
1 | package Object::Remote::MiniLoop; |
2 | |
3 | use IO::Select; |
befabdee |
4 | use Time::HiRes qw(time); |
5d59cb98 |
5 | use Object::Remote::Logging qw( :log :dlog ); |
9e72f0cf |
6 | use Moo; |
7 | |
8 | # this is ro because we only actually set it using local in sub run |
9 | |
10 | has is_running => (is => 'ro', clearer => 'stop'); |
11 | |
12 | has _read_watches => (is => 'ro', default => sub { {} }); |
13 | has _read_select => (is => 'ro', default => sub { IO::Select->new }); |
14 | |
fbd3b8ec |
15 | has _write_watches => (is => 'ro', default => sub { {} }); |
16 | has _write_select => (is => 'ro', default => sub { IO::Select->new }); |
17 | |
befabdee |
18 | has _timers => (is => 'ro', default => sub { [] }); |
19 | |
9e72f0cf |
20 | sub pass_watches_to { |
21 | my ($self, $new_loop) = @_; |
a63cd862 |
22 | log_debug { "passing watches to new run loop" }; |
9e72f0cf |
23 | foreach my $fh ($self->_read_select->handles) { |
24 | $new_loop->watch_io( |
25 | handle => $fh, |
26 | on_read_ready => $self->_read_watches->{$fh} |
27 | ); |
28 | } |
fbd3b8ec |
29 | foreach my $fh ($self->_write_select->handles) { |
30 | $new_loop->watch_io( |
31 | handle => $fh, |
32 | on_write_ready => $self->_write_watches->{$fh} |
33 | ); |
34 | } |
9e72f0cf |
35 | } |
36 | |
37 | sub watch_io { |
38 | my ($self, %watch) = @_; |
39 | my $fh = $watch{handle}; |
90115979 |
40 | Dlog_debug { "Adding IO watch for $_" } $fh; |
41 | |
42 | #TODO if this works out non-blocking support |
43 | #will need to be integrated in a way that |
44 | #is compatible with Windows which has no |
7790ca36 |
45 | #non-blocking support - see also ::ReadChannel |
6b7b2732 |
46 | if (0) { |
47 | Dlog_warn { "setting file handle to be non-blocking: $_" } $fh; |
48 | use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK); |
49 | my $flags = fcntl($fh, F_GETFL, 0) |
50 | or die "Can't get flags for the socket: $!\n"; |
51 | $flags = fcntl($fh, F_SETFL, $flags | O_NONBLOCK) |
52 | or die "Can't set flags for the socket: $!\n"; |
53 | } |
54 | |
9e72f0cf |
55 | if (my $cb = $watch{on_read_ready}) { |
90115979 |
56 | log_trace { "IO watcher is registering with select for reading" }; |
9e72f0cf |
57 | $self->_read_select->add($fh); |
58 | $self->_read_watches->{$fh} = $cb; |
59 | } |
fbd3b8ec |
60 | if (my $cb = $watch{on_write_ready}) { |
90115979 |
61 | log_trace { "IO watcher is registering with select for writing" }; |
fbd3b8ec |
62 | $self->_write_select->add($fh); |
63 | $self->_write_watches->{$fh} = $cb; |
64 | } |
498c4ad5 |
65 | return; |
9e72f0cf |
66 | } |
67 | |
68 | sub unwatch_io { |
69 | my ($self, %watch) = @_; |
70 | my $fh = $watch{handle}; |
9d64d2d9 |
71 | Dlog_debug { "Removing IO watch for $_" } $fh; |
9e72f0cf |
72 | if ($watch{on_read_ready}) { |
9d64d2d9 |
73 | log_trace { "IO watcher is removing read from select()" }; |
9e72f0cf |
74 | $self->_read_select->remove($fh); |
75 | delete $self->_read_watches->{$fh}; |
76 | } |
fbd3b8ec |
77 | if ($watch{on_write_ready}) { |
9d64d2d9 |
78 | log_trace { "IO watcher is removing write from select()" }; |
fbd3b8ec |
79 | $self->_write_select->remove($fh); |
80 | delete $self->_write_watches->{$fh}; |
81 | } |
befabdee |
82 | return; |
83 | } |
84 | |
85 | sub watch_time { |
86 | my ($self, %watch) = @_; |
87 | my $at = $watch{at} || do { |
88 | die "watch_time requires at or after" unless my $after = $watch{after}; |
89 | time() + $after; |
90 | }; |
91 | die "watch_time requires code" unless my $code = $watch{code}; |
92 | my $timers = $self->_timers; |
93 | my $new = [ $at => $code ]; |
94 | @{$timers} = sort { $a->[0] <=> $b->[0] } @{$timers}, $new; |
5d59cb98 |
95 | log_debug { "Created new timer that expires at '$at'" }; |
befabdee |
96 | return "$new"; |
97 | } |
98 | |
99 | sub unwatch_time { |
100 | my ($self, $id) = @_; |
a63cd862 |
101 | log_debug { "Removing timer with id of '$id'" }; |
befabdee |
102 | @$_ = grep !($_ eq $id), @$_ for $self->_timers; |
103 | return; |
9e72f0cf |
104 | } |
105 | |
5d59cb98 |
106 | sub _next_timer_expires_delay { |
107 | my ($self) = @_; |
108 | my $timers = $self->_timers; |
a6786dda |
109 | #undef means no timeout, select only returns |
5d59cb98 |
110 | #when data is ready - when the system |
111 | #deadlocks the chatter from the timeout in |
112 | #select clogs up the logs |
9d64d2d9 |
113 | #TODO should make this an attribute |
5d59cb98 |
114 | my $delay_max = undef; |
115 | |
116 | return $delay_max unless @$timers; |
117 | my $duration = $timers->[0]->[0] - time; |
118 | |
119 | log_trace { "next timer fires in '$duration' seconds " }; |
120 | |
121 | if ($duration < 0) { |
122 | $duration = 0; |
a6786dda |
123 | } elsif (defined $delay_max && $duration > $delay_max) { |
124 | $duration = $delay_max; |
5d59cb98 |
125 | } |
a6786dda |
126 | |
5d59cb98 |
127 | return $duration; |
128 | } |
129 | |
9e72f0cf |
130 | sub loop_once { |
131 | my ($self) = @_; |
132 | my $read = $self->_read_watches; |
fbd3b8ec |
133 | my $write = $self->_write_watches; |
6b7b2732 |
134 | our $Loop_Entered = 1; |
5d59cb98 |
135 | my $read_count = 0; |
136 | my $write_count = 0; |
a63cd862 |
137 | my @c = caller; |
5d59cb98 |
138 | my $wait_time = $self->_next_timer_expires_delay; |
6b7b2732 |
139 | log_trace { sprintf("Run loop: loop_once() has been invoked by $c[1]:$c[2] with read:%i write:%i select timeout:%s", |
5d59cb98 |
140 | scalar(keys(%$read)), scalar(keys(%$write)), defined $wait_time ? $wait_time : 'indefinite' ) }; |
9d64d2d9 |
141 | #TODO The docs state that select() in some instances can return a socket as ready to |
142 | #read data even if reading from it would block and the recomendation is to set |
143 | #handles used with select() as non-blocking but Perl on Windows can not set a |
144 | #handle to use non-blocking IO - If Windows is not one of the operating |
145 | #systems where select() returns a handle that could block it would work to |
146 | #enable non-blocking mode only under Posix - the non-blocking sysread() |
147 | #logic would work unmodified for both blocking and non-blocking handles |
148 | #under Posix and Windows. |
fbd3b8ec |
149 | my ($readable, $writeable) = IO::Select->select( |
9d64d2d9 |
150 | #TODO how come select() isn't used to identify handles with errors on them? |
151 | #TODO is there a specific reason for a half second maximum wait duration? |
152 | #The two places I've found for the runloop to be invoked don't return control |
153 | #to the caller until a controlling variable interrupts the loop that invokes |
154 | #loop_once() - is this to allow that variable to be polled and exit the |
155 | #run loop? If so why isn't that behavior event driven and causes select() to |
156 | #return? |
5d59cb98 |
157 | $self->_read_select, $self->_write_select, undef, $wait_time |
158 | ); |
6b7b2732 |
159 | log_trace { |
5d59cb98 |
160 | my $readable_count = defined $readable ? scalar(@$readable) : 0; |
161 | my $writable_count = defined $writeable ? scalar(@$writeable) : 0; |
162 | "Run loop: select returned readable:$readable_count writeable:$writable_count"; |
a63cd862 |
163 | }; |
9e72f0cf |
164 | # I would love to trap errors in the select call but IO::Select doesn't |
165 | # differentiate between an error and a timeout. |
166 | # -- no, love, mst. |
6b7b2732 |
167 | |
168 | local $Loop_Entered; |
169 | |
a63cd862 |
170 | log_trace { "Reading from all ready filehandles" }; |
9e72f0cf |
171 | foreach my $fh (@$readable) { |
5d59cb98 |
172 | next unless $read->{$fh}; |
173 | $read_count++; |
174 | $read->{$fh}(); |
6b7b2732 |
175 | last if $Loop_Entered; |
fbd3b8ec |
176 | } |
a63cd862 |
177 | log_trace { "Writing to all ready filehandles" }; |
fbd3b8ec |
178 | foreach my $fh (@$writeable) { |
5d59cb98 |
179 | next unless $write->{$fh}; |
180 | $write_count++; |
181 | $write->{$fh}(); |
6b7b2732 |
182 | last if $Loop_Entered; |
9e72f0cf |
183 | } |
7790ca36 |
184 | |
5d59cb98 |
185 | log_trace { "Read from $read_count filehandles; wrote to $write_count filehandles" }; |
befabdee |
186 | my $timers = $self->_timers; |
187 | my $now = time(); |
a63cd862 |
188 | log_trace { "Checking timers" }; |
befabdee |
189 | while (@$timers and $timers->[0][0] <= $now) { |
5d59cb98 |
190 | Dlog_debug { "Found timer that needs to be executed: $_" } $timers->[0]; |
befabdee |
191 | (shift @$timers)->[1]->(); |
6b7b2732 |
192 | last if $Loop_Entered; |
befabdee |
193 | } |
6b7b2732 |
194 | log_trace { "Run loop: single loop is completed" }; |
befabdee |
195 | return; |
9e72f0cf |
196 | } |
197 | |
9d64d2d9 |
198 | #::Node and ::ConnectionServer use the want_run() / want_stop() |
199 | #counter to cause a run-loop to execute while something is active; |
200 | #the futures do this via a different mechanism |
6c597351 |
201 | sub want_run { |
202 | my ($self) = @_; |
5d59cb98 |
203 | Dlog_debug { "Run loop: Incrimenting want_running, is now $_" } |
204 | ++$self->{want_running}; |
6c597351 |
205 | } |
206 | |
207 | sub run_while_wanted { |
208 | my ($self) = @_; |
9d64d2d9 |
209 | log_debug { my $wr = $self->{want_running}; "Run loop: run_while_wanted() invoked; want_running: $wr" }; |
6c597351 |
210 | $self->loop_once while $self->{want_running}; |
a63cd862 |
211 | log_debug { "Run loop: run_while_wanted() completed" }; |
befabdee |
212 | return; |
6c597351 |
213 | } |
214 | |
215 | sub want_stop { |
216 | my ($self) = @_; |
5d59cb98 |
217 | if (! $self->{want_running}) { |
218 | log_debug { "Run loop: want_stop() was called but want_running was not true" }; |
219 | return; |
220 | } |
221 | Dlog_debug { "Run loop: decrimenting want_running, is now $_" } |
222 | --$self->{want_running}; |
6c597351 |
223 | } |
224 | |
9d64d2d9 |
225 | #TODO Hypothesis: Futures invoke run() which gives that future |
226 | #it's own localized is_running attribute - any adjustment to the |
227 | #is_running attribute outside of that future will not effect that |
228 | #future so each future winds up able to call run() and stop() at |
7790ca36 |
229 | #will with out interfering with each other - how about having |
230 | #run loop until the future becomes ready? |
9e72f0cf |
231 | sub run { |
232 | my ($self) = @_; |
6b7b2732 |
233 | log_trace { "Run loop: run() invoked" }; |
9e72f0cf |
234 | local $self->{is_running} = 1; |
235 | while ($self->is_running) { |
236 | $self->loop_once; |
237 | } |
6b7b2732 |
238 | log_trace { "Run loop: run() completed" }; |
befabdee |
239 | return; |
9e72f0cf |
240 | } |
241 | |
242 | 1; |