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# Before `make install' is performed this script should be runnable with
# `make test'. After `make install' it should work as `perl 1.t'
#########################
# change 'tests => 1' to 'tests => last_test_to_print';
use Test::More; # tests => 5;
use Sys::SigAction;
#########################
# Insert your test code below, the Test::More module is use()ed here so read
# its man page ( perldoc Test::More ) for help writing this test script.
use strict;
use warnings;
use Config;
use Carp qw( carp cluck croak confess );
use Data::Dumper;
use Sys::SigAction qw( set_sig_handler );
use POSIX ':signal_h' ;
my $tests = 4;
my @levels = ( 0 ,0 ,0 ,0 );
sub sighandler { print "in sighandler: level 1\n" ; $levels[1] = 2; }
#plan is a follows:
#
# A test that sets signal handlers in nested blocks, and tests that
# at each level of nesting, the signal handler at the next level up
# is still valid (for the same signal). The idea is that the scope of
# the block prevents the next level up signal handle from being overwritten.
#
SKIP: {
if ( ($Config{'archname'} =~ m/^arm/) and not ($ENV{'INLINE'}) )
{
print STDERR "
NOTE: arm systems seem to have a defective implementation of perl POSIX
signal handling. This test will segfault on these platforms, if
the block nesting is greater than 2... and I suspect if the block
nesting itself is corrupting the call stack somehow. This testing
will be skipped on arm* platforms.
All that said, this was an intentionally a very twisted test. It seems
unlikely that one would really want to do what this tests for. It is
reasonable to nest signal handlers in nested call stacks however:
See recursive_nested.t, which does run on arm platforms.
This test can be executed manually from the command line on arm platforms
as follows:
INLINE=1 perl -Ilib t/safe.t
Lincoln\n\n" ;
plan skip_all => "This test appears to corrupt perl's call stack on arm platforms" ;
}
plan tests => $tests;
my $ctx0 = set_sig_handler( SIGALRM ,sub { print "in sighandler: level 0\n" ; $levels[0] = 1; } );
eval {
my $ctx1 = set_sig_handler( 'ALRM' ,'sighandler' );
#print Dumper( $ctx1 );
if ( 1 ) {
eval {
my $ctx2 = set_sig_handler( SIGALRM ,sub { print "in sighandler: level 2\n"; $levels[2] = 3; } );
eval {
my $ctx3 = set_sig_handler( 'ALRM' ,sub { print "in sighandler: level 3\n"; $levels[3] = 4; } );
kill ALRM => $$;
#undef $ctx3;
};
if ($@) { warn "handler died: $@\n"; }
kill ALRM => $$;
};
if ( $@ ) { warn "error: $@\n"; }
}
kill ALRM => $$;
};
if ( $@ ) { warn "error: $@\n"; }
eval {
kill ALRM => $$;
};
if ($@ ) { warn "error :$@\n"; }
my $i = 0;
foreach my $level ( @levels )
{
ok( $level ,"(level $i is not 0 as expected)" );
print "level $i = $level\n" ;
$i++;
}
}
exit;
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