# Carp::Heavy uses some variables in common with Carp.
package Carp;
=head1 NAME
Carp::Heavy - heavy machinery, no user serviceable parts inside
=cut
# use strict; # not yet
# On one line so MakeMaker will see it.
use Carp; our $VERSION = $Carp::VERSION;
our ($CarpLevel, $MaxArgNums, $MaxEvalLen, $MaxArgLen, $Verbose);
sub caller_info {
my $i = shift(@_) + 1;
package DB;
my %call_info;
@call_info{
qw(pack file line sub has_args wantarray evaltext is_require)
} = caller($i);
unless (defined $call_info{pack}) {
return ();
}
my $sub_name = Carp::get_subname(\%call_info);
if ($call_info{has_args}) {
my @args = map {Carp::format_arg($_)} @DB::args;
if ($MaxArgNums and @args > $MaxArgNums) { # More than we want to show?
$#args = $MaxArgNums;
push @args, '...';
}
# Push the args onto the subroutine
$sub_name .= '(' . join (', ', @args) . ')';
}
$call_info{sub_name} = $sub_name;
return wantarray() ? %call_info : \%call_info;
}
# Transform an argument to a function into a string.
sub format_arg {
my $arg = shift;
if (not defined($arg)) {
$arg = 'undef';
}
elsif (ref($arg)) {
$arg = defined($overload::VERSION) ? overload::StrVal($arg) : "$arg";
}
$arg =~ s/'/\\'/g;
$arg = str_len_trim($arg, $MaxArgLen);
# Quote it?
$arg = "'$arg'" unless $arg =~ /^-?[\d.]+\z/;
# The following handling of "control chars" is direct from
# the original code - I think it is broken on Unicode though.
# Suggestions?
$arg =~ s/([[:cntrl:]]|[[:^ascii:]])/sprintf("\\x{%x}",ord($1))/eg;
return $arg;
}
# Takes an inheritance cache and a package and returns
# an anon hash of known inheritances and anon array of
# inheritances which consequences have not been figured
# for.
sub get_status {
my $cache = shift;
my $pkg = shift;
$cache->{$pkg} ||= [{$pkg => $pkg}, [trusts_directly($pkg)]];
return @{$cache->{$pkg}};
}
# Takes the info from caller() and figures out the name of
# the sub/require/eval
sub get_subname {
my $info = shift;
if (defined($info->{evaltext})) {
my $eval = $info->{evaltext};
if ($info->{is_require}) {
return "require $eval";
}
else {
$eval =~ s/([\\\'])/\\$1/g;
return "eval '" . str_len_trim($eval, $MaxEvalLen) . "'";
}
}
return ($info->{sub} eq '(eval)') ? 'eval {...}' : $info->{sub};
}
# Figures out what call (from the point of view of the caller)
# the long error backtrace should start at.
sub long_error_loc {
my $i;
my $lvl = $CarpLevel;
{
my $pkg = caller(++$i);
unless(defined($pkg)) {
# This *shouldn't* happen.
if (%Internal) {
local %Internal;
$i = long_error_loc();
last;
}
else {
# OK, now I am irritated.
return 2;
}
}
redo if $CarpInternal{$pkg};
redo unless 0 > --$lvl;
redo if $Internal{$pkg};
}
return $i - 1;
}
sub longmess_heavy {
return @_ if ref($_[0]); # don't break references as exceptions
my $i = long_error_loc();
return ret_backtrace($i, @_);
}
# Returns a full stack backtrace starting from where it is
# told.
sub ret_backtrace {
my ($i, @error) = @_;
my $mess;
my $err = join '', @error;
$i++;
my $tid_msg = '';
if (defined &Thread::tid) {
my $tid = Thread->self->tid;
$tid_msg = " thread $tid" if $tid;
}
{ if ($err =~ /\n$/) { # extra block to localise $1 etc
$mess = $err;
}
else {
my %i = caller_info($i);
$mess = "$err at $i{file} line $i{line}$tid_msg\n";
}}
while (my %i = caller_info(++$i)) {
$mess .= "\t$i{sub_name} called at $i{file} line $i{line}$tid_msg\n";
}
return $mess;
}
sub ret_summary {
my ($i, @error) = @_;
my $mess;
my $err = join '', @error;
$i++;
my $tid_msg = '';
if (defined &Thread::tid) {
my $tid = Thread->self->tid;
$tid_msg = " thread $tid" if $tid;
}
my %i = caller_info($i);
return "$err at $i{file} line $i{line}$tid_msg\n";
}
sub short_error_loc {
my $cache;
my $i = 1;
my $lvl = $CarpLevel;
{
my $called = caller($i++);
my $caller = caller($i);
return 0 unless defined($caller); # What happened?
redo if $Internal{$caller};
redo if $CarpInternal{$called};
redo if trusts($called, $caller, $cache);
redo if trusts($caller, $called, $cache);
redo unless 0 > --$lvl;
}
return $i - 1;
}
sub shortmess_heavy {
return longmess_heavy(@_) if $Verbose;
return @_ if ref($_[0]); # don't break references as exceptions
my $i = short_error_loc();
if ($i) {
ret_summary($i, @_);
}
else {
longmess_heavy(@_);
}
}
# If a string is too long, trims it with ...
sub str_len_trim {
my $str = shift;
my $max = shift || 0;
if (2 < $max and $max < length($str)) {
substr($str, $max - 3) = '...';
}
return $str;
}
# Takes two packages and an optional cache. Says whether the
# first inherits from the second.
#
# Recursive versions of this have to work to avoid certain
# possible endless loops, and when following long chains of
# inheritance are less efficient.
sub trusts {
my $child = shift;
my $parent = shift;
my $cache = shift || {};
my ($known, $partial) = get_status($cache, $child);
# Figure out consequences until we have an answer
while (@$partial and not exists $known->{$parent}) {
my $anc = shift @$partial;
next if exists $known->{$anc};
$known->{$anc}++;
my ($anc_knows, $anc_partial) = get_status($cache, $anc);
my @found = keys %$anc_knows;
@$known{@found} = ();
push @$partial, @$anc_partial;
}
return exists $known->{$parent};
}
# Takes a package and gives a list of those trusted directly
sub trusts_directly {
my $class = shift;
no strict 'refs';
no warnings 'once';
return @{"$class\::CARP_NOT"}
? @{"$class\::CARP_NOT"}
: @{"$class\::ISA"};
}
1;