warn "I'm confused";
die "I'm dying.\n";
+ use CGI::Carp qw(cluck);
+ cluck "I wouldn't do that if I were you";
+
+ use CGI::Carp qw(fatalsToBrowser);
+ die "Fatal error messages are now sent to browser";
+
=head1 DESCRIPTION
CGI scripts have a nasty habit of leaving warning messages in the error
carpout() does not handle file locking on the log for you at this point.
-The real STDERR is not closed -- it is moved to SAVEERR. Some
+The real STDERR is not closed -- it is moved to CGI::Carp::SAVEERR. Some
servers, when dealing with CGI scripts, close their connection to the
-browser when the script closes STDOUT and STDERR. SAVEERR is used to
+browser when the script closes STDOUT and STDERR. CGI::Carp::SAVEERR is there to
prevent this from happening prematurely.
You can pass filehandles to carpout() in a variety of ways. The "correct"
... and so on
+FileHandle and other objects work as well.
+
Use of carpout() is not great for performance, so it is recommended
for debugging purposes or for moderate-use applications. A future
version of this module may delay redirecting STDERR until one of the
Nonfatal errors will still be directed to the log file only (unless redirected
with carpout).
+=head2 Changing the default message
+
+By default, the software error message is followed by a note to
+contact the Webmaster by e-mail with the time and date of the error.
+If this message is not to your liking, you can change it using the
+set_message() routine. This is not imported by default; you should
+import it on the use() line:
+
+ use CGI::Carp qw(fatalsToBrowser set_message);
+ set_message("It's not a bug, it's a feature!");
+
+You may also pass in a code reference in order to create a custom
+error message. At run time, your code will be called with the text
+of the error message that caused the script to die. Example:
+
+ use CGI::Carp qw(fatalsToBrowser set_message);
+ BEGIN {
+ sub handle_errors {
+ my $msg = shift;
+ print "<h1>Oh gosh</h1>";
+ print "<p>Got an error: $msg</p>";
+ }
+ set_message(\&handle_errors);
+ }
+
+In order to correctly intercept compile-time errors, you should call
+set_message() from within a BEGIN{} block.
+
+=head1 MAKING WARNINGS APPEAR AS HTML COMMENTS
+
+It is now also possible to make non-fatal errors appear as HTML
+comments embedded in the output of your program. To enable this
+feature, export the new "warningsToBrowser" subroutine. Since sending
+warnings to the browser before the HTTP headers have been sent would
+cause an error, any warnings are stored in an internal buffer until
+you call the warningsToBrowser() subroutine with a true argument:
+
+ use CGI::Carp qw(fatalsToBrowser warningsToBrowser);
+ use CGI qw(:standard);
+ print header();
+ warningsToBrowser(1);
+
+You may also give a false argument to warningsToBrowser() to prevent
+warnings from being sent to the browser while you are printing some
+content where HTML comments are not allowed:
+
+ warningsToBrowser(0); # disable warnings
+ print "<script type=\"text/javascript\"><!--\n";
+ print_some_javascript_code();
+ print "//--></script>\n";
+ warningsToBrowser(1); # re-enable warnings
+
+Note: In this respect warningsToBrowser() differs fundamentally from
+fatalsToBrowser(), which you should never call yourself!
+
+=head1 OVERRIDING THE NAME OF THE PROGRAM
+
+CGI::Carp includes the name of the program that generated the error or
+warning in the messages written to the log and the browser window.
+Sometimes, Perl can get confused about what the actual name of the
+executed program was. In these cases, you can override the program
+name that CGI::Carp will use for all messages.
+
+The quick way to do that is to tell CGI::Carp the name of the program
+in its use statement. You can do that by adding
+"name=cgi_carp_log_name" to your "use" statement. For example:
+
+ use CGI::Carp qw(name=cgi_carp_log_name);
+
+. If you want to change the program name partway through the program,
+you can use the C<set_progname()> function instead. It is not
+exported by default, you must import it explicitly by saying
+
+ use CGI::Carp qw(set_progname);
+
+Once you've done that, you can change the logged name of the program
+at any time by calling
+
+ set_progname(new_program_name);
+
+You can set the program back to the default by calling
+
+ set_progname(undef);
+
+Note that this override doesn't happen until after the program has
+compiled, so any compile-time errors will still show up with the
+non-overridden program name
+
=head1 CHANGE LOG
1.05 carpout() added and minor corrections by Marc Hedlund
1.06 fatalsToBrowser() no longer aborts for fatal errors within
eval() statements.
+1.08 set_message() added and carpout() expanded to allow for FileHandle
+ objects.
+
+1.09 set_message() now allows users to pass a code REFERENCE for
+ really custom error messages. croak and carp are now
+ exported by default. Thanks to Gunther Birznieks for the
+ patches.
+
+1.10 Patch from Chris Dean (ctdean@cogit.com) to allow
+ module to run correctly under mod_perl.
+
+1.11 Changed order of > and < escapes.
+
+1.12 Changed die() on line 217 to CORE::die to avoid B<-w> warning.
+
+1.13 Added cluck() to make the module orthogonal with Carp.
+ More mod_perl related fixes.
+
+1.20 Patch from Ilmari Karonen (perl@itz.pp.sci.fi): Added
+ warningsToBrowser(). Replaced <CODE> tags with <PRE> in
+ fatalsToBrowser() output.
+
+1.23 ineval() now checks both $^S and inspects the message for the "eval" pattern
+ (hack alert!) in order to accomodate various combinations of Perl and
+ mod_perl.
+
+1.24 Patch from Scott Gifford (sgifford@suspectclass.com): Add support
+ for overriding program name.
+
+1.26 Replaced CORE::GLOBAL::die with the evil $SIG{__DIE__} because the
+ former isn't working in some people's hands. There is no such thing
+ as reliable exception handling in Perl.
+
+1.27 Replaced tell STDOUT with bytes=tell STDOUT.
+
=head1 AUTHORS
-Lincoln D. Stein <lstein@genome.wi.mit.edu>. Feel free to redistribute
-this under the Perl Artistic License.
+Copyright 1995-2002, Lincoln D. Stein. All rights reserved.
+This library is free software; you can redistribute it and/or modify
+it under the same terms as Perl itself.
+
+Address bug reports and comments to: lstein@cshl.org
=head1 SEE ALSO
Carp, CGI::Base, CGI::BasePlus, CGI::Request, CGI::MiniSvr, CGI::Form,
CGI::Response
+ if (defined($CGI::Carp::PROGNAME))
+ {
+ $file = $CGI::Carp::PROGNAME;
+ }
=cut
require 5.000;
use Exporter;
-use Carp;
+#use Carp;
+BEGIN {
+ require Carp;
+ *CORE::GLOBAL::die = \&CGI::Carp::die;
+}
+
+use File::Spec;
@ISA = qw(Exporter);
@EXPORT = qw(confess croak carp);
-@EXPORT_OK = qw(carpout fatalsToBrowser);
+@EXPORT_OK = qw(carpout fatalsToBrowser warningsToBrowser wrap set_message set_progname cluck ^name= die);
$main::SIG{__WARN__}=\&CGI::Carp::warn;
-$main::SIG{__DIE__}=\&CGI::Carp::die;
-$CGI::Carp::VERSION = '1.06';
+
+$CGI::Carp::VERSION = '1.27';
+$CGI::Carp::CUSTOM_MSG = undef;
+
# fancy import routine detects and handles 'errorWrap' specially.
sub import {
my $pkg = shift;
my(%routines);
- grep($routines{$_}++,@_);
- $WRAP++ if $routines{'fatalsToBrowser'};
+ my(@name);
+
+ if (@name=grep(/^name=/,@_))
+ {
+ my($n) = (split(/=/,$name[0]))[1];
+ set_progname($n);
+ @_=grep(!/^name=/,@_);
+ }
+
+ grep($routines{$_}++,@_,@EXPORT);
+ $WRAP++ if $routines{'fatalsToBrowser'} || $routines{'wrap'};
+ $WARN++ if $routines{'warningsToBrowser'};
my($oldlevel) = $Exporter::ExportLevel;
$Exporter::ExportLevel = 1;
Exporter::import($pkg,keys %routines);
$Exporter::ExportLevel = $oldlevel;
+ $main::SIG{__DIE__} =\&CGI::Carp::die if $routines{'fatalsToBrowser'};
+# $pkg->export('CORE::GLOBAL','die');
}
# These are the originals
-sub realwarn { warn(@_); }
-sub realdie { die(@_); }
+sub realwarn { CORE::warn(@_); }
+sub realdie { CORE::die(@_); }
sub id {
my $level = shift;
my($pack,$file,$line,$sub) = caller($level);
- my($id) = $file=~m|([^/]+)$|;
+ my($dev,$dirs,$id) = File::Spec->splitpath($file);
return ($file,$line,$id);
}
sub stamp {
my $time = scalar(localtime);
my $frame = 0;
- my ($id,$pack,$file);
- do {
- $id = $file;
- ($pack,$file) = caller($frame++);
- } until !$file;
- ($id) = $id=~m|([^/]+)$|;
+ my ($id,$pack,$file,$dev,$dirs);
+ if (defined($CGI::Carp::PROGNAME)) {
+ $id = $CGI::Carp::PROGNAME;
+ } else {
+ do {
+ $id = $file;
+ ($pack,$file) = caller($frame++);
+ } until !$file;
+ }
+ ($dev,$dirs,$id) = File::Spec->splitpath($id);
return "[$time] $id: ";
}
+sub set_progname {
+ $CGI::Carp::PROGNAME = shift;
+ return $CGI::Carp::PROGNAME;
+}
+
+
sub warn {
my $message = shift;
my($file,$line,$id) = id(1);
$message .= " at $file line $line.\n" unless $message=~/\n$/;
+ _warn($message) if $WARN;
my $stamp = stamp;
$message=~s/^/$stamp/gm;
realwarn $message;
}
+sub _warn {
+ my $msg = shift;
+ if ($EMIT_WARNINGS) {
+ # We need to mangle the message a bit to make it a valid HTML
+ # comment. This is done by substituting similar-looking ISO
+ # 8859-1 characters for <, > and -. This is a hack.
+ $msg =~ tr/<>-/\253\273\255/;
+ chomp $msg;
+ print STDOUT "<!-- warning: $msg -->\n";
+ } else {
+ push @WARNINGS, $msg;
+ }
+}
+
+
+# The mod_perl package Apache::Registry loads CGI programs by calling
+# eval. These evals don't count when looking at the stack backtrace.
+sub _longmess {
+ my $message = Carp::longmess();
+ $message =~ s,eval[^\n]+(ModPerl|Apache)/Registry\w*\.pm.*,,s
+ if exists $ENV{MOD_PERL};
+ return $message;
+}
+
+sub ineval {
+ (exists $ENV{MOD_PERL} ? 0 : $^S) || _longmess() =~ /eval [\{\']/m
+}
+
sub die {
- my $message = shift;
- my $time = scalar(localtime);
+ my ($arg) = @_;
+ realdie @_ if ineval;
+ if (!ref($arg)) {
+ $arg = join("", @_);
my($file,$line,$id) = id(1);
- return undef if $file=~/^\(eval/;
- $message .= " at $file line $line.\n" unless $message=~/\n$/;
- &fatalsToBrowser($message) if $WRAP;
- my $stamp = stamp;
- $message=~s/^/$stamp/gm;
- realdie $message;
+ $arg .= " at $file line $line." unless $arg=~/\n$/;
+ &fatalsToBrowser($arg) if $WRAP;
+ if (($arg =~ /\n$/) || !exists($ENV{MOD_PERL})) {
+ my $stamp = stamp;
+ $arg=~s/^/$stamp/gm;
+ }
+ if ($arg !~ /\n$/) {
+ $arg .= "\n";
+ }
+ }
+ realdie $arg;
}
-# Avoid generating "subroutine redefined" warnings with the following
-# hack:
-{
- local $^W=0;
- eval <<EOF;
-sub confess { CGI::Carp::die Carp::longmess \@_; }
-sub croak { CGI::Carp::die Carp::shortmess \@_; }
-sub carp { CGI::Carp::warn Carp::shortmess \@_; }
-EOF
- ;
+sub set_message {
+ $CGI::Carp::CUSTOM_MSG = shift;
+ return $CGI::Carp::CUSTOM_MSG;
}
+sub confess { CGI::Carp::die Carp::longmess @_; }
+sub croak { CGI::Carp::die Carp::shortmess @_; }
+sub carp { CGI::Carp::warn Carp::shortmess @_; }
+sub cluck { CGI::Carp::warn Carp::longmess @_; }
+
# We have to be ready to accept a filehandle as a reference
# or a string.
sub carpout {
my($in) = @_;
- $in = $$in if ref($in); # compatability with Marc's method;
- my($no) = fileno($in);
- unless (defined($no)) {
- my($package) = caller;
- my($handle) = $in=~/[':]/ ? $in : "$package\:\:$in";
- $no = fileno($handle);
- }
- die "Invalid filehandle $in\n" unless $no;
+ my($no) = fileno(to_filehandle($in));
+ realdie("Invalid filehandle $in\n") unless defined $no;
open(SAVEERR, ">&STDERR");
open(STDERR, ">&$no") or
( print SAVEERR "Unable to redirect STDERR: $!\n" and exit(1) );
}
+sub warningsToBrowser {
+ $EMIT_WARNINGS = @_ ? shift : 1;
+ _warn(shift @WARNINGS) while $EMIT_WARNINGS and @WARNINGS;
+}
+
# headers
sub fatalsToBrowser {
- my($msg) = @_;
- $msg=~s/>/>/g;
- $msg=~s/</</g;
- print STDOUT "Content-type: text/html\n\n";
- print STDOUT <<END;
-<H1>Software error:</H1>
-<CODE>$msg</CODE>
-<P>
-Please send mail to this site's webmaster for help.
+ my($msg) = @_;
+ $msg=~s/&/&/g;
+ $msg=~s/>/>/g;
+ $msg=~s/</</g;
+ $msg=~s/\"/"/g;
+ my($wm) = $ENV{SERVER_ADMIN} ?
+ qq[the webmaster (<a href="mailto:$ENV{SERVER_ADMIN}">$ENV{SERVER_ADMIN}</a>)] :
+ "this site's webmaster";
+ my ($outer_message) = <<END;
+For help, please send mail to $wm, giving this error message
+and the time and date of the error.
END
+ ;
+ my $mod_perl = exists $ENV{MOD_PERL};
+
+ warningsToBrowser(1); # emit warnings before dying
+
+ if ($CUSTOM_MSG) {
+ if (ref($CUSTOM_MSG) eq 'CODE') {
+ print STDOUT "Content-type: text/html\n\n"
+ unless $mod_perl;
+ &$CUSTOM_MSG($msg); # nicer to perl 5.003 users
+ return;
+ } else {
+ $outer_message = $CUSTOM_MSG;
+ }
+ }
+
+ my $mess = <<END;
+<h1>Software error:</h1>
+<pre>$msg</pre>
+<p>
+$outer_message
+</p>
+END
+ ;
+
+ if ($mod_perl) {
+ require mod_perl;
+ if ($mod_perl::VERSION >= 1.99) {
+ $mod_perl = 2;
+ require Apache::RequestRec;
+ require Apache::RequestIO;
+ require Apache::RequestUtil;
+ require APR::Pool;
+ require ModPerl::Util;
+ require Apache::Response;
+ }
+ my $r = Apache->request;
+ # If bytes have already been sent, then
+ # we print the message out directly.
+ # Otherwise we make a custom error
+ # handler to produce the doc for us.
+ if ($r->bytes_sent) {
+ $r->print($mess);
+ $mod_perl == 2 ? ModPerl::Util::exit(0) : $r->exit;
+ } else {
+ # MSIE won't display a custom 500 response unless it is >512 bytes!
+ if ($ENV{HTTP_USER_AGENT} =~ /MSIE/) {
+ $mess = "<!-- " . (' ' x 513) . " -->\n$mess";
+ }
+ $r->custom_response(500,$mess);
+ }
+ } else {
+ my $bytes_written = eval{tell STDOUT};
+ if (defined $bytes_written && $bytes_written > 0) {
+ print STDOUT $mess;
+ }
+ else {
+ print STDOUT "Content-type: text/html\n\n";
+ print STDOUT $mess;
+ }
+ }
+}
+
+# Cut and paste from CGI.pm so that we don't have the overhead of
+# always loading the entire CGI module.
+sub to_filehandle {
+ my $thingy = shift;
+ return undef unless $thingy;
+ return $thingy if UNIVERSAL::isa($thingy,'GLOB');
+ return $thingy if UNIVERSAL::isa($thingy,'FileHandle');
+ if (!ref($thingy)) {
+ my $caller = 1;
+ while (my $package = caller($caller++)) {
+ my($tmp) = $thingy=~/[\':]/ ? $thingy : "$package\:\:$thingy";
+ return $tmp if defined(fileno($tmp));
+ }
+ }
+ return undef;
}
1;