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Comparing Coro/Coro/Semaphore.pm (file contents):
Revision 1.16 by root, Thu Aug 30 02:58:17 2001 UTC vs.
Revision 1.25 by root, Tue Nov 27 03:11:48 2001 UTC

… …
31 31
32=cut 32=cut
33 33
34package Coro::Semaphore; 34package Coro::Semaphore;
35 35
36no warnings qw(uninitialized);
37
36use Coro (); 38use Coro ();
37 39
38$VERSION = 0.45; 40$VERSION = 0.52;
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 my $self = shift;
62 while ($self->[0] <= 0) { 68 while ($_[0][0] <= 0) {
63 push @{$self->[1]}, $Coro::current; 69 push @{$_[0][1]}, $Coro::current;
64 Coro::schedule; 70 Coro::schedule;
65 } 71 }
66 --$self->[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 $timeout and return;
83 }
84
85 --$_[0][0];
86 return 1;
67} 87}
68 88
69=item $sem->up 89=item $sem->up
70 90
71Unlock the semaphore again. 91Unlock the semaphore again.
72 92
73=cut 93=cut
74 94
75sub up { 95sub up {
76 my $self = shift;
77 if (++$self->[0] > 0) { 96 if (++$_[0][0] > 0) {
78 (shift @{$self->[1]})->ready if @{$self->[1]}; 97 (shift @{$_[0][1]})->ready if @{$_[0][1]};
79 } 98 }
80} 99}
81 100
82=item $sem->try 101=item $sem->try
83 102
… …
85otherwise return false and leave the semaphore unchanged. 104otherwise return false and leave the semaphore unchanged.
86 105
87=cut 106=cut
88 107
89sub try { 108sub try {
90 my $self = shift;
91 if ($self->[0] > 0) { 109 if ($_[0][0] > 0) {
92 --$self->[0]; 110 --$_[0][0];
93 return 1; 111 return 1;
94 } else { 112 } else {
95 return 0; 113 return 0;
96 } 114 }
97} 115}
… …
110=item $guard = $sem->guard 128=item $guard = $sem->guard
111 129
112This method calls C<down> and then creates a guard object. When the guard 130This method calls C<down> and then creates a guard object. When the guard
113object is destroyed it automatically calls C<up>. 131object is destroyed it automatically calls C<up>.
114 132
133=item $guard = $sem->timed_guard($timeout)
134
135Like C<guard>, but returns undef if semaphore couldn't be acquired within
136$timeout seconds, otherwise the guard object.
137
115=cut 138=cut
116 139
117sub guard { 140sub guard {
118 &down; 141 &down;
119 # double indirection because bless works on the referenced 142 # double indirection because bless works on the referenced
120 # object, not (only) on the reference itself. 143 # object, not (only) on the reference itself.
121 bless \\$_[0], Coro::Semaphore::Guard::; 144 bless \\$_[0], Coro::Semaphore::guard;
122} 145}
123 146
147sub timed_guard {
148 &timed_down
149 ? bless \\$_[0], Coro::Semaphore::guard
150 : ();
151}
152
124sub Coro::Semaphore::Guard::DESTROY { 153sub Coro::Semaphore::guard::DESTROY {
125 &up(${${$_[0]}}); 154 &up(${${$_[0]}});
126} 155}
127 156
1281; 1571;
129 158

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