lib/AnyEvent/Strict.pm

=head1 NAME

AnyEvent::Strict - force strict mode on for the whole process

=head1 SYNOPSIS

   use AnyEvent::Strict;
   # strict mode now switched on

=head1 DESCRIPTION

This module implements AnyEvent's strict mode.

Loading it makes AnyEvent check all arguments to AnyEvent-methods, at the
expense of being slower (often the argument checking takes longer than the
actual function). It also wraps all callbacks to check for modifications
of C<$_>, which indicates a programming bug inside the watcher callback.

Normally, you don't load this module yourself but instead use it
indirectly via the C<PERL_ANYEVENT_STRICT> environment variable (see
L<AnyEvent>). However, this module can be loaded manually at any time.

=cut

package AnyEvent::Strict;

use Carp qw(confess);
use Errno ();
use POSIX ();

$Carp::Internal{AE}               = 1;
$Carp::Internal{AnyEvent::Strict} = 1;

use AnyEvent (); BEGIN { AnyEvent::common_sense }

AnyEvent::_isa_hook 1 => "AnyEvent::Strict", 1;

BEGIN {
   if (defined &Internals::SvREADONLY) {
      # readonly available (at least 5.8.9+, working better in 5.10.1+)
      *wrap = sub {
         my $cb = shift;

         sub {
            local $_;
            Internals::SvREADONLY $_, 1;
            &$cb;
         }
      };
   } else {
      # or not :/
      my $magic = []; # a unique magic value

      *wrap = sub {
         my $cb = shift;

         sub {
            local $_ = $magic;

            &$cb;

            if (!ref $_ || $_ != $magic) {
               require AnyEvent::Debug;
               die "callback $cb (" . AnyEvent::Debug::cb2str ($cb) . ") modified \$_ without restoring it.\n";
            }
         }
      };
   }
}

our (@FD_INUSE, $FD_I);
our $FD_CHECK_W = AE::timer 4, 4, sub {
   my $cnt = (@FD_INUSE < 100 * 10 ? int @FD_INUSE * 0.1 : 100) || 10;

   if ($FD_I <= 0) {
      #pop @FD_INUSE while @FD_INUSE && !$FD_INUSE[-1];
      $FD_I = @FD_INUSE
         or return; # empty
   }

   $cnt = $FD_I if $cnt > $FD_I;

   eval {
      do {
         !$FD_INUSE[--$FD_I]
            or (POSIX::lseek $FD_I, 0, 1) != -1
            or $! != Errno::EBADF
            or die;
      } while --$cnt;
      1
   } or AE::log crit => "File descriptor $FD_I registered with AnyEvent but prematurely closed, event loop might malfunction.";
};

sub io {
   my $class = shift;
   my (%arg, $fh, $cb, $fd) = @_;

   ref $arg{cb}
      or confess "AnyEvent->io called with illegal cb argument '$arg{cb}'";
   $cb = wrap delete $arg{cb};
 
   $arg{poll} =~ /^[rw]$/
      or confess "AnyEvent->io called with illegal poll argument '$arg{poll}'";

   $fh = delete $arg{fh};

   if ($fh =~ /^\s*\d+\s*$/) {
      $fd = $fh;
      ($fh) = AnyEvent::_dupfh $arg{poll}, $fh;
   } else {
      defined eval { $fd = fileno $fh }
         or confess "AnyEvent->io called with illegal fh argument '$fh'";
   }

   -f $fh
      and confess "AnyEvent->io called with fh argument pointing to a file";

   delete $arg{poll};
 
   confess "AnyEvent->io called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   ++$FD_INUSE[$fd];

   bless [
      $fd,
      $class->SUPER::io (@_, cb => $cb)
   ], "AnyEvent::Strict::io";
}

sub AnyEvent::Strict::io::DESTROY {
   --$FD_INUSE[$_[0][0]];
}

sub timer {
   my $class = shift;
   my %arg = @_;

   ref $arg{cb}
      or confess "AnyEvent->timer called with illegal cb argument '$arg{cb}'";
   my $cb = wrap delete $arg{cb};
 
   exists $arg{after}
      or confess "AnyEvent->timer called without mandatory 'after' parameter";
   delete $arg{after};
 
   !$arg{interval} or $arg{interval} > 0
      or confess "AnyEvent->timer called with illegal interval argument '$arg{interval}'";
   delete $arg{interval};
 
   confess "AnyEvent->timer called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   $class->SUPER::timer (@_, cb => $cb)
}

sub signal {
   my $class = shift;
   my %arg = @_;

   ref $arg{cb}
      or confess "AnyEvent->signal called with illegal cb argument '$arg{cb}'";
   my $cb = wrap delete $arg{cb};
 
   defined AnyEvent::Base::sig2num $arg{signal} and $arg{signal} == 0
      or confess "AnyEvent->signal called with illegal signal name '$arg{signal}'";
   delete $arg{signal};
 
   confess "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   $class->SUPER::signal (@_, cb => $cb)
}

sub child {
   my $class = shift;
   my %arg = @_;

   ref $arg{cb}
      or confess "AnyEvent->child called with illegal cb argument '$arg{cb}'";
   my $cb = wrap delete $arg{cb};
 
   $arg{pid} =~ /^-?\d+$/
      or confess "AnyEvent->child called with malformed pid value '$arg{pid}'";
   delete $arg{pid};
 
   confess "AnyEvent->child called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   $class->SUPER::child (@_, cb => $cb)
}

sub idle {
   my $class = shift;
   my %arg = @_;

   ref $arg{cb}
      or confess "AnyEvent->idle called with illegal cb argument '$arg{cb}'";
   my $cb = wrap delete $arg{cb};
 
   confess "AnyEvent->idle called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   $class->SUPER::idle (@_, cb => $cb)
}

sub condvar {
   my $class = shift;
   my %arg = @_;

   !exists $arg{cb} or ref $arg{cb}
      or confess "AnyEvent->condvar called with illegal cb argument '$arg{cb}'";
   my @cb = exists $arg{cb} ? (cb => wrap delete $arg{cb}) : ();
 
   confess "AnyEvent->condvar called with unsupported parameter(s) " . join ", ", keys %arg
      if keys %arg;

   $class->SUPER::condvar (@cb);
}

sub time {
   my $class = shift;

   @_
      and confess "AnyEvent->time wrongly called with paramaters";

   $class->SUPER::time (@_)
}

sub now {
   my $class = shift;

   @_
      and confess "AnyEvent->now wrongly called with paramaters";

   $class->SUPER::now (@_)
}

=head1 AUTHOR

 Marc Lehmann <schmorp@schmorp.de>
 http://anyevent.schmorp.de

=cut

1

Revision:	1.44
Committed:	Sat Jul 7 14:03:05 2018 UTC (5 years, 10 months ago) by root
Branch:	MAIN
CVS Tags:	rel-7_16, rel-7_15, HEAD
Changes since 1.43:	+1 -1 lines
Log Message:	* empty log message *
#	Content
1	=head1 NAME
2
3	AnyEvent::Strict - force strict mode on for the whole process
4
5	=head1 SYNOPSIS
6
7	use AnyEvent::Strict;
8	# strict mode now switched on
9
10	=head1 DESCRIPTION
11
12	This module implements AnyEvent's strict mode.
13
14	Loading it makes AnyEvent check all arguments to AnyEvent-methods, at the
15	expense of being slower (often the argument checking takes longer than the
16	actual function). It also wraps all callbacks to check for modifications
17	of C<$_>, which indicates a programming bug inside the watcher callback.
18
19	Normally, you don't load this module yourself but instead use it
20	indirectly via the C<PERL_ANYEVENT_STRICT> environment variable (see
21	L<AnyEvent>). However, this module can be loaded manually at any time.
22
23	=cut
24
25	package AnyEvent::Strict;
26
27	use Carp qw(confess);
28	use Errno ();
29	use POSIX ();
30
31	$Carp::Internal{AE} = 1;
32	$Carp::Internal{AnyEvent::Strict} = 1;
33
34	use AnyEvent (); BEGIN { AnyEvent::common_sense }
35
36	AnyEvent::_isa_hook 1 => "AnyEvent::Strict", 1;
37
38	BEGIN {
39	if (defined &Internals::SvREADONLY) {
40	# readonly available (at least 5.8.9+, working better in 5.10.1+)
41	*wrap = sub {
42	my $cb = shift;
43
44	sub {
45	local $_;
46	Internals::SvREADONLY $_, 1;
47	&$cb;
48	}
49	};
50	} else {
51	# or not :/
52	my $magic = []; # a unique magic value
53
54	*wrap = sub {
55	my $cb = shift;
56
57	sub {
58	local $_ = $magic;
59
60	&$cb;
61
62	if (!ref $_ \|\| $_ != $magic) {
63	require AnyEvent::Debug;
64	die "callback $cb (" . AnyEvent::Debug::cb2str ($cb) . ") modified \$_ without restoring it.\n";
65	}
66	}
67	};
68	}
69	}
70
71	our (@FD_INUSE, $FD_I);
72	our $FD_CHECK_W = AE::timer 4, 4, sub {
73	my $cnt = (@FD_INUSE < 100 * 10 ? int @FD_INUSE * 0.1 : 100) \|\| 10;
74
75	if ($FD_I <= 0) {
76	#pop @FD_INUSE while @FD_INUSE && !$FD_INUSE[-1];
77	$FD_I = @FD_INUSE
78	or return; # empty
79	}
80
81	$cnt = $FD_I if $cnt > $FD_I;
82
83	eval {
84	do {
85	!$FD_INUSE[--$FD_I]
86	or (POSIX::lseek $FD_I, 0, 1) != -1
87	or $! != Errno::EBADF
88	or die;
89	} while --$cnt;
90	1
91	} or AE::log crit => "File descriptor $FD_I registered with AnyEvent but prematurely closed, event loop might malfunction.";
92	};
93
94	sub io {
95	my $class = shift;
96	my (%arg, $fh, $cb, $fd) = @_;
97
98	ref $arg{cb}
99	or confess "AnyEvent->io called with illegal cb argument '$arg{cb}'";
100	$cb = wrap delete $arg{cb};
101
102	$arg{poll} =~ /^[rw]$/
103	or confess "AnyEvent->io called with illegal poll argument '$arg{poll}'";
104
105	$fh = delete $arg{fh};
106
107	if ($fh =~ /^\s\d+\s$/) {
108	$fd = $fh;
109	($fh) = AnyEvent::_dupfh $arg{poll}, $fh;
110	} else {
111	defined eval { $fd = fileno $fh }
112	or confess "AnyEvent->io called with illegal fh argument '$fh'";
113	}
114
115	-f $fh
116	and confess "AnyEvent->io called with fh argument pointing to a file";
117
118	delete $arg{poll};
119
120	confess "AnyEvent->io called with unsupported parameter(s) " . join ", ", keys %arg
121	if keys %arg;
122
123	++$FD_INUSE[$fd];
124
125	bless [
126	$fd,
127	$class->SUPER::io (@_, cb => $cb)
128	], "AnyEvent::Strict::io";
129	}
130
131	sub AnyEvent::Strict::io::DESTROY {
132	--$FD_INUSE[$_[0][0]];
133	}
134
135	sub timer {
136	my $class = shift;
137	my %arg = @_;
138
139	ref $arg{cb}
140	or confess "AnyEvent->timer called with illegal cb argument '$arg{cb}'";
141	my $cb = wrap delete $arg{cb};
142
143	exists $arg{after}
144	or confess "AnyEvent->timer called without mandatory 'after' parameter";
145	delete $arg{after};
146
147	!$arg{interval} or $arg{interval} > 0
148	or confess "AnyEvent->timer called with illegal interval argument '$arg{interval}'";
149	delete $arg{interval};
150
151	confess "AnyEvent->timer called with unsupported parameter(s) " . join ", ", keys %arg
152	if keys %arg;
153
154	$class->SUPER::timer (@_, cb => $cb)
155	}
156
157	sub signal {
158	my $class = shift;
159	my %arg = @_;
160
161	ref $arg{cb}
162	or confess "AnyEvent->signal called with illegal cb argument '$arg{cb}'";
163	my $cb = wrap delete $arg{cb};
164
165	defined AnyEvent::Base::sig2num $arg{signal} and $arg{signal} == 0
166	or confess "AnyEvent->signal called with illegal signal name '$arg{signal}'";
167	delete $arg{signal};
168
169	confess "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg
170	if keys %arg;
171
172	$class->SUPER::signal (@_, cb => $cb)
173	}
174
175	sub child {
176	my $class = shift;
177	my %arg = @_;
178
179	ref $arg{cb}
180	or confess "AnyEvent->child called with illegal cb argument '$arg{cb}'";
181	my $cb = wrap delete $arg{cb};
182
183	$arg{pid} =~ /^-?\d+$/
184	or confess "AnyEvent->child called with malformed pid value '$arg{pid}'";
185	delete $arg{pid};
186
187	confess "AnyEvent->child called with unsupported parameter(s) " . join ", ", keys %arg
188	if keys %arg;
189
190	$class->SUPER::child (@_, cb => $cb)
191	}
192
193	sub idle {
194	my $class = shift;
195	my %arg = @_;
196
197	ref $arg{cb}
198	or confess "AnyEvent->idle called with illegal cb argument '$arg{cb}'";
199	my $cb = wrap delete $arg{cb};
200
201	confess "AnyEvent->idle called with unsupported parameter(s) " . join ", ", keys %arg
202	if keys %arg;
203
204	$class->SUPER::idle (@_, cb => $cb)
205	}
206
207	sub condvar {
208	my $class = shift;
209	my %arg = @_;
210
211	!exists $arg{cb} or ref $arg{cb}
212	or confess "AnyEvent->condvar called with illegal cb argument '$arg{cb}'";
213	my @cb = exists $arg{cb} ? (cb => wrap delete $arg{cb}) : ();
214
215	confess "AnyEvent->condvar called with unsupported parameter(s) " . join ", ", keys %arg
216	if keys %arg;
217
218	$class->SUPER::condvar (@cb);
219	}
220
221	sub time {
222	my $class = shift;
223
224	@_
225	and confess "AnyEvent->time wrongly called with paramaters";
226
227	$class->SUPER::time (@_)
228	}
229
230	sub now {
231	my $class = shift;
232
233	@_
234	and confess "AnyEvent->now wrongly called with paramaters";
235
236	$class->SUPER::now (@_)
237	}
238
239	=head1 AUTHOR
240
241	Marc Lehmann <schmorp@schmorp.de>
242	http://anyevent.schmorp.de
243
244	=cut
245
246	1
247