Edit: /usr/share/perl5/sigtrap.pm (7611B)
package sigtrap;
=head1 NAME
sigtrap - Perl pragma to enable simple signal handling
=cut
use Carp;
$VERSION = 1.04;
$Verbose ||= 0;
sub import {
my $pkg = shift;
my $handler = \&handler_traceback;
my $saw_sig = 0;
my $untrapped = 0;
local $_;
Arg_loop:
while (@_) {
$_ = shift;
if (/^[A-Z][A-Z0-9]*$/) {
$saw_sig++;
unless ($untrapped and $SIG{$_} and $SIG{$_} ne 'DEFAULT') {
print "Installing handler $handler for $_\n" if $Verbose;
$SIG{$_} = $handler;
}
}
elsif ($_ eq 'normal-signals') {
unshift @_, grep(exists $SIG{$_}, qw(HUP INT PIPE TERM));
}
elsif ($_ eq 'error-signals') {
unshift @_, grep(exists $SIG{$_},
qw(ABRT BUS EMT FPE ILL QUIT SEGV SYS TRAP));
}
elsif ($_ eq 'old-interface-signals') {
unshift @_,
grep(exists $SIG{$_},
qw(ABRT BUS EMT FPE ILL PIPE QUIT SEGV SYS TERM TRAP));
}
elsif ($_ eq 'stack-trace') {
$handler = \&handler_traceback;
}
elsif ($_ eq 'die') {
$handler = \&handler_die;
}
elsif ($_ eq 'handler') {
@_ or croak "No argument specified after 'handler'";
$handler = shift;
unless (ref $handler or $handler eq 'IGNORE'
or $handler eq 'DEFAULT') {
require Symbol;
$handler = Symbol::qualify($handler, (caller)[0]);
}
}
elsif ($_ eq 'untrapped') {
$untrapped = 1;
}
elsif ($_ eq 'any') {
$untrapped = 0;
}
elsif ($_ =~ /^\d/) {
$VERSION >= $_ or croak "sigtrap.pm version $_ required,"
. " but this is only version $VERSION";
}
else {
croak "Unrecognized argument $_";
}
}
unless ($saw_sig) {
@_ = qw(old-interface-signals);
goto Arg_loop;
}
}
sub handler_die {
croak "Caught a SIG$_[0]";
}
sub handler_traceback {
package DB; # To get subroutine args.
$SIG{'ABRT'} = DEFAULT;
kill 'ABRT', $$ if $panic++;
syswrite(STDERR, 'Caught a SIG', 12);
syswrite(STDERR, $_[0], length($_[0]));
syswrite(STDERR, ' at ', 4);
($pack,$file,$line) = caller;
syswrite(STDERR, $file, length($file));
syswrite(STDERR, ' line ', 6);
syswrite(STDERR, $line, length($line));
syswrite(STDERR, "\n", 1);
# Now go for broke.
for ($i = 1; ($p,$f,$l,$s,$h,$w,$e,$r) = caller($i); $i++) {
@a = ();
for (@args) {
s/([\'\\])/\\$1/g;
s/([^\0]*)/'$1'/
unless /^(?: -?[\d.]+ | \*[\w:]* )$/x;
s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
push(@a, $_);
}
$w = $w ? '@ = ' : '$ = ';
$a = $h ? '(' . join(', ', @a) . ')' : '';
$e =~ s/\n\s*\;\s*\Z// if $e;
$e =~ s/[\\\']/\\$1/g if $e;
if ($r) {
$s = "require '$e'";
} elsif (defined $r) {
$s = "eval '$e'";
} elsif ($s eq '(eval)') {
$s = "eval {...}";
}
$f = "file `$f'" unless $f eq '-e';
$mess = "$w$s$a called from $f line $l\n";
syswrite(STDERR, $mess, length($mess));
}
kill 'ABRT', $$;
}
1;
__END__
=head1 SYNOPSIS
use sigtrap;
use sigtrap qw(stack-trace old-interface-signals); # equivalent
use sigtrap qw(BUS SEGV PIPE ABRT);
use sigtrap qw(die INT QUIT);
use sigtrap qw(die normal-signals);
use sigtrap qw(die untrapped normal-signals);
use sigtrap qw(die untrapped normal-signals
stack-trace any error-signals);
use sigtrap 'handler' => \&my_handler, 'normal-signals';
use sigtrap qw(handler my_handler normal-signals
stack-trace error-signals);
=head1 DESCRIPTION
The B
pragma is a simple interface to installing signal
handlers. You can have it install one of two handlers supplied by
B itself (one which provides a Perl stack trace and one which
simply Cs), or alternately you can supply your own handler for it
to install. It can be told only to install a handler for signals which
are either untrapped or ignored. It has a couple of lists of signals to
trap, plus you can supply your own list of signals.
The arguments passed to the C