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Comparing Coro/Coro/Semaphore.pm (file contents):
Revision 1.18 by root, Sun Sep 2 01:03:53 2001 UTC vs.
Revision 1.53 by root, Wed Feb 1 23:59:41 2006 UTC

… …
31 31
32=cut 32=cut
33 33
34package Coro::Semaphore; 34package Coro::Semaphore;
35 35
36BEGIN { eval { require warnings } && warnings->unimport ("uninitialized") }
37
36use Coro (); 38use Coro ();
37 39
38$VERSION = 0.49; 40$VERSION = 1.9;
39 41
40=item new [inital count] 42=item new [inital count]
41 43
42Creates a new sempahore object with the given initial lock count. The 44Creates a new sempahore object with the given initial lock count. The
43default lock count is 1, which means it is unlocked by default. Zero (or 45default lock count is 1, which means it is unlocked by default. Zero (or
… …
53=item $sem->down 55=item $sem->down
54 56
55Decrement the counter, therefore "locking" the semaphore. This method 57Decrement the counter, therefore "locking" the semaphore. This method
56waits until the semaphore is available if the counter is zero. 58waits until the semaphore is available if the counter is zero.
57 59
60=item $status = $sem->timed_down($timeout)
61
62Like C<down>, but returns false if semaphore couldn't be acquired within
63$timeout seconds, otherwise true.
64
58=cut 65=cut
59 66
60sub down { 67sub down {
61 while ($_[0][0] <= 0) { 68 while ($_[0][0] <= 0) {
62 push @{$_[0][1]}, $Coro::current; 69 push @{$_[0][1]}, $Coro::current;
63 Coro::schedule; 70 Coro::schedule;
64 } 71 }
65 --$_[0][0]; 72 --$_[0][0];
73}
74
75sub timed_down {
76 require Coro::Timer;
77 my $timeout = Coro::Timer::timeout($_[1]);
78
79 while ($_[0][0] <= 0) {
80 push @{$_[0][1]}, $Coro::current;
81 Coro::schedule;
82 if ($timeout) {
83 # ugly as hell. slow, too, btw!
84 for (0..$#{$_[0][1]}) {
85 if ($_[0][1][$_] == $Coro::current) {
86 splice @{$_[0][1]}, $_, 1;
87 return;
88 }
89 }
90 die;
91 }
92 }
93
94 --$_[0][0];
95 return 1;
66} 96}
67 97
68=item $sem->up 98=item $sem->up
69 99
70Unlock the semaphore again. 100Unlock the semaphore again.
… …
107=item $guard = $sem->guard 137=item $guard = $sem->guard
108 138
109This method calls C<down> and then creates a guard object. When the guard 139This method calls C<down> and then creates a guard object. When the guard
110object is destroyed it automatically calls C<up>. 140object is destroyed it automatically calls C<up>.
111 141
142=item $guard = $sem->timed_guard($timeout)
143
144Like C<guard>, but returns undef if semaphore couldn't be acquired within
145$timeout seconds, otherwise the guard object.
146
112=cut 147=cut
113 148
114sub guard { 149sub guard {
115 &down; 150 &down;
116 # double indirection because bless works on the referenced 151 # double indirection because bless works on the referenced
117 # object, not (only) on the reference itself. 152 # object, not (only) on the reference itself.
118 bless \\$_[0], Coro::Semaphore::Guard::; 153 bless \\$_[0], Coro::Semaphore::guard::;
119} 154}
120 155
156sub timed_guard {
157 &timed_down
158 ? bless \\$_[0], Coro::Semaphore::guard::
159 : ();
160}
161
121sub Coro::Semaphore::Guard::DESTROY { 162sub Coro::Semaphore::guard::DESTROY {
122 &up(${${$_[0]}}); 163 &up(${${$_[0]}});
123} 164}
124
1251;
126 165
127=back 166=back
128 167
129=head1 AUTHOR 168=head1 AUTHOR
130 169
131 Marc Lehmann <pcg@goof.com> 170 Marc Lehmann <schmorp@schmorp.de>
132 http://www.goof.com/pcg/marc/ 171 http://home.schmorp.de/
133 172
134=cut 173=cut
135 174
1751
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