package Carp;
-# This package is heavily used. Be small. Be fast. Be good.
-# Comments added by Andy Wardley <abw@kfs.org> 09-Apr-98, based on an
-# _almost_ complete understanding of the package. Corrections and
-# comments are welcome.
-
-# longmess() crawls all the way up the stack reporting on all the function
-# calls made. The error string, $error, is originally constructed from the
-# arguments passed into longmess() via confess(), cluck() or shortmess().
-# This gets appended with the stack trace messages which are generated for
-# each function call on the stack.
-
-sub longmess_heavy {
- return @_ if ref $_[0];
- my $error = join '', @_;
- my $mess = "";
- my $i = 1 + $CarpLevel;
- my ($pack,$file,$line,$sub,$hargs,$eval,$require);
- my (@a);
- #
- # crawl up the stack....
- #
- while (do { { package DB; @a = caller($i++) } } ) {
- # get copies of the variables returned from caller()
- ($pack,$file,$line,$sub,$hargs,undef,$eval,$require) = @a;
- #
- # if the $error error string is newline terminated then it
- # is copied into $mess. Otherwise, $mess gets set (at the end of
- # the 'else {' section below) to one of two things. The first time
- # through, it is set to the "$error at $file line $line" message.
- # $error is then set to 'called' which triggers subsequent loop
- # iterations to append $sub to $mess before appending the "$error
- # at $file line $line" which now actually reads "called at $file line
- # $line". Thus, the stack trace message is constructed:
- #
- # first time: $mess = $error at $file line $line
- # subsequent times: $mess .= $sub $error at $file line $line
- # ^^^^^^
- # "called"
- if ($error =~ m/\n$/) {
- $mess .= $error;
- } else {
- # Build a string, $sub, which names the sub-routine called.
- # This may also be "require ...", "eval '...' or "eval {...}"
- if (defined $eval) {
- if ($require) {
- $sub = "require $eval";
- } else {
- $eval =~ s/([\\\'])/\\$1/g;
- if ($MaxEvalLen && length($eval) > $MaxEvalLen) {
- substr($eval,$MaxEvalLen) = '...';
- }
- $sub = "eval '$eval'";
- }
- } elsif ($sub eq '(eval)') {
- $sub = 'eval {...}';
- }
- # if there are any arguments in the sub-routine call, format
- # them according to the format variables defined earlier in
- # this file and join them onto the $sub sub-routine string
- if ($hargs) {
- # we may trash some of the args so we take a copy
- @a = @DB::args; # must get local copy of args
- # don't print any more than $MaxArgNums
- if ($MaxArgNums and @a > $MaxArgNums) {
- # cap the length of $#a and set the last element to '...'
- $#a = $MaxArgNums;
- $a[$#a] = "...";
- }
- for (@a) {
- # set args to the string "undef" if undefined
- $_ = "undef", next unless defined $_;
- if (ref $_) {
- # dunno what this is for...
- $_ .= '';
- s/'/\\'/g;
- }
- else {
- s/'/\\'/g;
- # terminate the string early with '...' if too long
- substr($_,$MaxArgLen) = '...'
- if $MaxArgLen and $MaxArgLen < length;
- }
- # 'quote' arg unless it looks like a number
- $_ = "'$_'" unless /^-?[\d.]+$/;
- # print high-end chars as 'M-<char>'
- s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg;
- # print remaining control chars as ^<char>
- s/([\0-\37\177])/sprintf("^%c",ord($1)^64)/eg;
- }
- # append ('all', 'the', 'arguments') to the $sub string
- $sub .= '(' . join(', ', @a) . ')';
- }
- # here's where the error message, $mess, gets constructed
- $mess .= "\t$sub " if $error eq "called";
- $mess .= "$error at $file line $line";
- if (defined &Thread::tid) {
- my $tid = Thread->self->tid;
- $mess .= " thread $tid" if $tid;
- }
- $mess .= "\n";
- }
- # we don't need to print the actual error message again so we can
- # change this to "called" so that the string "$error at $file line
- # $line" makes sense as "called at $file line $line".
- $error = "called";
- }
- # this kludge circumvents die's incorrect handling of NUL
- my $msg = \($mess || $error);
- $$msg =~ tr/\0//d;
- $$msg;
-}
-
-
-# shortmess() is called by carp() and croak() to skip all the way up to
-# the top-level caller's package and report the error from there. confess()
-# and cluck() generate a full stack trace so they call longmess() to
-# generate that. In verbose mode shortmess() calls longmess() so
-# you always get a stack trace
-
-sub shortmess_heavy { # Short-circuit &longmess if called via multiple packages
- goto &longmess_heavy if $Verbose;
- return @_ if ref $_[0];
- my $error = join '', @_;
- my ($prevpack) = caller(1);
- my $extra = $CarpLevel;
- my $i = 2;
- my ($pack,$file,$line);
- # when reporting an error, we want to report it from the context of the
- # calling package. So what is the calling package? Within a module,
- # there may be many calls between methods and perhaps between sub-classes
- # and super-classes, but the user isn't interested in what happens
- # inside the package. We start by building a hash array which keeps
- # track of all the packages to which the calling package belongs. We
- # do this by examining its @ISA variable. Any call from a base class
- # method (one of our caller's @ISA packages) can be ignored
- my %isa = ($prevpack,1);
-
- # merge all the caller's @ISA packages into %isa.
- @isa{@{"${prevpack}::ISA"}} = ()
- if(@{"${prevpack}::ISA"});
-
- # now we crawl up the calling stack and look at all the packages in
- # there. For each package, we look to see if it has an @ISA and then
- # we see if our caller features in that list. That would imply that
- # our caller is a derived class of that package and its calls can also
- # be ignored
- while (($pack,$file,$line) = caller($i++)) {
- if(@{$pack . "::ISA"}) {
- my @i = @{$pack . "::ISA"};
- my %i;
- @i{@i} = ();
- # merge any relevant packages into %isa
- @isa{@i,$pack} = ()
- if(exists $i{$prevpack} || exists $isa{$pack});
- }
-
- # and here's where we do the ignoring... if the package in
- # question is one of our caller's base or derived packages then
- # we can ignore it (skip it) and go onto the next (but note that
- # the continue { } block below gets called every time)
- next
- if(exists $isa{$pack});
-
- # Hey! We've found a package that isn't one of our caller's
- # clan....but wait, $extra refers to the number of 'extra' levels
- # we should skip up. If $extra > 0 then this is a false alarm.
- # We must merge the package into the %isa hash (so we can ignore it
- # if it pops up again), decrement $extra, and continue.
- if ($extra-- > 0) {
- %isa = ($pack,1);
- @isa{@{$pack . "::ISA"}} = ()
- if(@{$pack . "::ISA"});
- }
- else {
- # OK! We've got a candidate package. Time to construct the
- # relevant error message and return it. die() doesn't like
- # to be given NUL characters (which $msg may contain) so we
- # remove them first.
- my $msg;
- $msg = "$error at $file line $line";
- if (defined &Thread::tid) {
- my $tid = Thread->self->tid;
- $mess .= " thread $tid" if $tid;
- }
- $msg .= "\n";
- $msg =~ tr/\0//d;
- return $msg;
- }
- }
- continue {
- $prevpack = $pack;
- }
-
- # uh-oh! It looks like we crawled all the way up the stack and
- # never found a candidate package. Oh well, let's call longmess
- # to generate a full stack trace. We use the magical form of 'goto'
- # so that this shortmess() function doesn't appear on the stack
- # to further confuse longmess() about it's calling package.
- goto &longmess_heavy;
-}
+# On one line so MakeMaker will see it.
+use Carp; our $VERSION = $Carp::VERSION;
1;
+
+# Most of the machinery of Carp used to be there.
+# It has been moved in Carp.pm now, but this placeholder remains for
+# the benefit of modules that like to preload Carp::Heavy directly.
https://perl5.git.perl.org / perl5.git / blobdiff