ÿØÿà JFIF    ÿÛ „ ( %!1!%*+...983,7(-.- lib64/perl5/vendor_perl/IPC/Semaphore.pm000064400000014432152347133610013737 0ustar00################################################################################ # # Version 2.x, Copyright (C) 2007-2013, Marcus Holland-Moritz . # Version 1.x, Copyright (C) 1997, Graham Barr . # # This program is free software; you can redistribute it and/or # modify it under the same terms as Perl itself. # ################################################################################ package IPC::Semaphore; use IPC::SysV qw(GETNCNT GETZCNT GETVAL SETVAL GETPID GETALL SETALL IPC_STAT IPC_SET IPC_RMID); use strict; use vars qw($VERSION); use Carp; $VERSION = '2.07'; # Figure out if we have support for native sized types my $N = do { my $foo = eval { pack "L!", 0 }; $@ ? '' : '!' }; { package IPC::Semaphore::stat; use Class::Struct qw(struct); struct 'IPC::Semaphore::stat' => [ uid => '$', gid => '$', cuid => '$', cgid => '$', mode => '$', ctime => '$', otime => '$', nsems => '$', ]; } sub new { @_ == 4 || croak 'new ' . __PACKAGE__ . '( KEY, NSEMS, FLAGS )'; my $class = shift; my $id = semget($_[0],$_[1],$_[2]); defined($id) ? bless \$id, $class : undef; } sub id { my $self = shift; $$self; } sub remove { my $self = shift; my $result = semctl($$self,0,IPC_RMID,0); undef $$self; $result; } sub getncnt { @_ == 2 || croak '$sem->getncnt( SEM )'; my $self = shift; my $sem = shift; my $v = semctl($$self,$sem,GETNCNT,0); $v ? 0 + $v : undef; } sub getzcnt { @_ == 2 || croak '$sem->getzcnt( SEM )'; my $self = shift; my $sem = shift; my $v = semctl($$self,$sem,GETZCNT,0); $v ? 0 + $v : undef; } sub getval { @_ == 2 || croak '$sem->getval( SEM )'; my $self = shift; my $sem = shift; my $v = semctl($$self,$sem,GETVAL,0); $v ? 0 + $v : undef; } sub getpid { @_ == 2 || croak '$sem->getpid( SEM )'; my $self = shift; my $sem = shift; my $v = semctl($$self,$sem,GETPID,0); $v ? 0 + $v : undef; } sub op { @_ >= 4 || croak '$sem->op( OPLIST )'; my $self = shift; croak 'Bad arg count' if @_ % 3; my $data = pack("s$N*",@_); semop($$self,$data); } sub stat { my $self = shift; my $data = ""; semctl($$self,0,IPC_STAT,$data) or return undef; IPC::Semaphore::stat->new->unpack($data); } sub set { my $self = shift; my $ds; if(@_ == 1) { $ds = shift; } else { croak 'Bad arg count' if @_ % 2; my %arg = @_; $ds = $self->stat or return undef; my($key,$val); $ds->$key($val) while(($key,$val) = each %arg); } my $v = semctl($$self,0,IPC_SET,$ds->pack); $v ? 0 + $v : undef; } sub getall { my $self = shift; my $data = ""; semctl($$self,0,GETALL,$data) or return (); (unpack("s$N*",$data)); } sub setall { my $self = shift; my $data = pack("s$N*",@_); semctl($$self,0,SETALL,$data); } sub setval { @_ == 3 || croak '$sem->setval( SEM, VAL )'; my $self = shift; my $sem = shift; my $val = shift; semctl($$self,$sem,SETVAL,$val); } 1; __END__ =head1 NAME IPC::Semaphore - SysV Semaphore IPC object class =head1 SYNOPSIS use IPC::SysV qw(IPC_PRIVATE S_IRUSR S_IWUSR IPC_CREAT); use IPC::Semaphore; $sem = IPC::Semaphore->new(IPC_PRIVATE, 10, S_IRUSR | S_IWUSR | IPC_CREAT); $sem->setall( (0) x 10); @sem = $sem->getall; $ncnt = $sem->getncnt; $zcnt = $sem->getzcnt; $ds = $sem->stat; $sem->remove; =head1 DESCRIPTION A class providing an object based interface to SysV IPC semaphores. =head1 METHODS =over 4 =item new ( KEY , NSEMS , FLAGS ) Create a new semaphore set associated with C. C is the number of semaphores in the set. A new set is created if =over 4 =item * C is equal to C =item * C does not already have a semaphore identifier associated with it, and C & IPC_CREAT> is true. =back On creation of a new semaphore set C is used to set the permissions. Be careful not to set any flags that the Sys V IPC implementation does not allow: in some systems setting execute bits makes the operations fail. =item getall Returns the values of the semaphore set as an array. =item getncnt ( SEM ) Returns the number of processes waiting for the semaphore C to become greater than its current value =item getpid ( SEM ) Returns the process id of the last process that performed an operation on the semaphore C. =item getval ( SEM ) Returns the current value of the semaphore C. =item getzcnt ( SEM ) Returns the number of processes waiting for the semaphore C to become zero. =item id Returns the system identifier for the semaphore set. =item op ( OPLIST ) C is a list of operations to pass to C. C is a concatenation of smaller lists, each which has three values. The first is the semaphore number, the second is the operation and the last is a flags value. See L for more details. For example $sem->op( 0, -1, IPC_NOWAIT, 1, 1, IPC_NOWAIT ); =item remove Remove and destroy the semaphore set from the system. =item set ( STAT ) =item set ( NAME => VALUE [, NAME => VALUE ...] ) C will set the following values of the C structure associated with the semaphore set. uid gid mode (only the permission bits) C accepts either a stat object, as returned by the C method, or a list of I-I pairs. =item setall ( VALUES ) Sets all values in the semaphore set to those given on the C list. C must contain the correct number of values. =item setval ( N , VALUE ) Set the Cth value in the semaphore set to C =item stat Returns an object of type C which is a sub-class of C. It provides the following fields. For a description of these fields see your system documentation. uid gid cuid cgid mode ctime otime nsems =back =head1 SEE ALSO L, L, L, L, L =head1 AUTHORS Graham Barr , Marcus Holland-Moritz =head1 COPYRIGHT Version 2.x, Copyright (C) 2007-2013, Marcus Holland-Moritz. Version 1.x, Copyright (c) 1997, Graham Barr. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut usr/share/perl5/Thread/Semaphore.pm000064400000016636152361224410013212 0ustar00package Thread::Semaphore; use strict; use warnings; our $VERSION = '2.13'; $VERSION = eval $VERSION; use threads::shared; use Scalar::Util 1.10 qw(looks_like_number); # Predeclarations for internal functions my ($validate_arg); # Create a new semaphore optionally with specified count (count defaults to 1) sub new { my $class = shift; my $val :shared = 1; if (@_) { $val = shift; if (! defined($val) || ! looks_like_number($val) || (int($val) != $val)) { require Carp; $val = 'undef' if (! defined($val)); Carp::croak("Semaphore initializer is not an integer: $val"); } } return bless(\$val, $class); } # Decrement a semaphore's count (decrement amount defaults to 1) sub down { my $sema = shift; my $dec = @_ ? $validate_arg->(shift) : 1; lock($$sema); cond_wait($$sema) until ($$sema >= $dec); $$sema -= $dec; } # Decrement a semaphore's count only if count >= decrement value # (decrement amount defaults to 1) sub down_nb { my $sema = shift; my $dec = @_ ? $validate_arg->(shift) : 1; lock($$sema); my $ok = ($$sema >= $dec); $$sema -= $dec if $ok; return $ok; } # Decrement a semaphore's count even if the count goes below 0 # (decrement amount defaults to 1) sub down_force { my $sema = shift; my $dec = @_ ? $validate_arg->(shift) : 1; lock($$sema); $$sema -= $dec; } # Decrement a semaphore's count with timeout # (timeout in seconds; decrement amount defaults to 1) sub down_timed { my $sema = shift; my $timeout = $validate_arg->(shift); my $dec = @_ ? $validate_arg->(shift) : 1; lock($$sema); my $abs = time() + $timeout; until ($$sema >= $dec) { return if !cond_timedwait($$sema, $abs); } $$sema -= $dec; return 1; } # Increment a semaphore's count (increment amount defaults to 1) sub up { my $sema = shift; my $inc = @_ ? $validate_arg->(shift) : 1; lock($$sema); ($$sema += $inc) > 0 and cond_broadcast($$sema); } ### Internal Functions ### # Validate method argument $validate_arg = sub { my $arg = shift; if (! defined($arg) || ! looks_like_number($arg) || (int($arg) != $arg) || ($arg < 1)) { require Carp; my ($method) = (caller(1))[3]; $method =~ s/Thread::Semaphore:://; $arg = 'undef' if (! defined($arg)); Carp::croak("Argument to semaphore method '$method' is not a positive integer: $arg"); } return $arg; }; 1; =head1 NAME Thread::Semaphore - Thread-safe semaphores =head1 VERSION This document describes Thread::Semaphore version 2.13 =head1 SYNOPSIS use Thread::Semaphore; my $s = Thread::Semaphore->new(); $s->down(); # Also known as the semaphore P operation. # The guarded section is here $s->up(); # Also known as the semaphore V operation. # Decrement the semaphore only if it would immediately succeed. if ($s->down_nb()) { # The guarded section is here $s->up(); } # Forcefully decrement the semaphore even if its count goes below 0. $s->down_force(); # The default value for semaphore operations is 1 my $s = Thread::Semaphore->new($initial_value); $s->down($down_value); $s->up($up_value); if ($s->down_nb($down_value)) { ... $s->up($up_value); } $s->down_force($down_value); =head1 DESCRIPTION Semaphores provide a mechanism to regulate access to resources. Unlike locks, semaphores aren't tied to particular scalars, and so may be used to control access to anything you care to use them for. Semaphores don't limit their values to zero and one, so they can be used to control access to some resource that there may be more than one of (e.g., filehandles). Increment and decrement amounts aren't fixed at one either, so threads can reserve or return multiple resources at once. =head1 METHODS =over 8 =item ->new() =item ->new(NUMBER) C creates a new semaphore, and initializes its count to the specified number (which must be an integer). If no number is specified, the semaphore's count defaults to 1. =item ->down() =item ->down(NUMBER) The C method decreases the semaphore's count by the specified number (which must be an integer >= 1), or by one if no number is specified. If the semaphore's count would drop below zero, this method will block until such time as the semaphore's count is greater than or equal to the amount you're Cing the semaphore's count by. This is the semaphore "P operation" (the name derives from the Dutch word "pak", which means "capture" -- the semaphore operations were named by the late Dijkstra, who was Dutch). =item ->down_nb() =item ->down_nb(NUMBER) The C method attempts to decrease the semaphore's count by the specified number (which must be an integer >= 1), or by one if no number is specified. If the semaphore's count would drop below zero, this method will return I, and the semaphore's count remains unchanged. Otherwise, the semaphore's count is decremented and this method returns I. =item ->down_force() =item ->down_force(NUMBER) The C method decreases the semaphore's count by the specified number (which must be an integer >= 1), or by one if no number is specified. This method does not block, and may cause the semaphore's count to drop below zero. =item ->down_timed(TIMEOUT) =item ->down_timed(TIMEOUT, NUMBER) The C method attempts to decrease the semaphore's count by 1 or by the specified number within the specified timeout period given in seconds (which must be an integer >= 0). If the semaphore's count would drop below zero, this method will block until either the semaphore's count is greater than or equal to the amount you're Cing the semaphore's count by, or until the timeout is reached. If the timeout is reached, this method will return I, and the semaphore's count remains unchanged. Otherwise, the semaphore's count is decremented and this method returns I. =item ->up() =item ->up(NUMBER) The C method increases the semaphore's count by the number specified (which must be an integer >= 1), or by one if no number is specified. This will unblock any thread that is blocked trying to C the semaphore if the C raises the semaphore's count above the amount that the C is trying to decrement it by. For example, if three threads are blocked trying to C a semaphore by one, and another thread Cs the semaphore by two, then two of the blocked threads (which two is indeterminate) will become unblocked. This is the semaphore "V operation" (the name derives from the Dutch word "vrij", which means "release"). =back =head1 NOTES Semaphores created by L can be used in both threaded and non-threaded applications. This allows you to write modules and packages that potentially make use of semaphores, and that will function in either environment. =head1 SEE ALSO Thread::Semaphore on MetaCPAN: L Code repository for CPAN distribution: L L, L Sample code in the I directory of this distribution on CPAN. =head1 MAINTAINER Jerry D. Hedden, Sjdhedden AT cpan DOT orgE> =head1 LICENSE This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =cut