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Diffstat (limited to 'Master/tlpkg/tlperl/lib/diagnostics.pm')
-rwxr-xr-x | Master/tlpkg/tlperl/lib/diagnostics.pm | 647 |
1 files changed, 647 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl/lib/diagnostics.pm b/Master/tlpkg/tlperl/lib/diagnostics.pm new file mode 100755 index 00000000000..7af5efa1778 --- /dev/null +++ b/Master/tlpkg/tlperl/lib/diagnostics.pm @@ -0,0 +1,647 @@ +package diagnostics; + +=head1 NAME + +diagnostics, splain - produce verbose warning diagnostics + +=head1 SYNOPSIS + +Using the C<diagnostics> pragma: + + use diagnostics; + use diagnostics -verbose; + + enable diagnostics; + disable diagnostics; + +Using the C<splain> standalone filter program: + + perl program 2>diag.out + splain [-v] [-p] diag.out + +Using diagnostics to get stack traces from a misbehaving script: + + perl -Mdiagnostics=-traceonly my_script.pl + +=head1 DESCRIPTION + +=head2 The C<diagnostics> Pragma + +This module extends the terse diagnostics normally emitted by both the +perl compiler and the perl interpreter (from running perl with a -w +switch or C<use warnings>), augmenting them with the more +explicative and endearing descriptions found in L<perldiag>. Like the +other pragmata, it affects the compilation phase of your program rather +than merely the execution phase. + +To use in your program as a pragma, merely invoke + + use diagnostics; + +at the start (or near the start) of your program. (Note +that this I<does> enable perl's B<-w> flag.) Your whole +compilation will then be subject(ed :-) to the enhanced diagnostics. +These still go out B<STDERR>. + +Due to the interaction between runtime and compiletime issues, +and because it's probably not a very good idea anyway, +you may not use C<no diagnostics> to turn them off at compiletime. +However, you may control their behaviour at runtime using the +disable() and enable() methods to turn them off and on respectively. + +The B<-verbose> flag first prints out the L<perldiag> introduction before +any other diagnostics. The $diagnostics::PRETTY variable can generate nicer +escape sequences for pagers. + +Warnings dispatched from perl itself (or more accurately, those that match +descriptions found in L<perldiag>) are only displayed once (no duplicate +descriptions). User code generated warnings a la warn() are unaffected, +allowing duplicate user messages to be displayed. + +This module also adds a stack trace to the error message when perl dies. +This is useful for pinpointing what caused the death. The B<-traceonly> (or +just B<-t>) flag turns off the explanations of warning messages leaving just +the stack traces. So if your script is dieing, run it again with + + perl -Mdiagnostics=-traceonly my_bad_script + +to see the call stack at the time of death. By supplying the B<-warntrace> +(or just B<-w>) flag, any warnings emitted will also come with a stack +trace. + +=head2 The I<splain> Program + +While apparently a whole nuther program, I<splain> is actually nothing +more than a link to the (executable) F<diagnostics.pm> module, as well as +a link to the F<diagnostics.pod> documentation. The B<-v> flag is like +the C<use diagnostics -verbose> directive. +The B<-p> flag is like the +$diagnostics::PRETTY variable. Since you're post-processing with +I<splain>, there's no sense in being able to enable() or disable() processing. + +Output from I<splain> is directed to B<STDOUT>, unlike the pragma. + +=head1 EXAMPLES + +The following file is certain to trigger a few errors at both +runtime and compiletime: + + use diagnostics; + print NOWHERE "nothing\n"; + print STDERR "\n\tThis message should be unadorned.\n"; + warn "\tThis is a user warning"; + print "\nDIAGNOSTIC TESTER: Please enter a <CR> here: "; + my $a, $b = scalar <STDIN>; + print "\n"; + print $x/$y; + +If you prefer to run your program first and look at its problem +afterwards, do this: + + perl -w test.pl 2>test.out + ./splain < test.out + +Note that this is not in general possible in shells of more dubious heritage, +as the theoretical + + (perl -w test.pl >/dev/tty) >& test.out + ./splain < test.out + +Because you just moved the existing B<stdout> to somewhere else. + +If you don't want to modify your source code, but still have on-the-fly +warnings, do this: + + exec 3>&1; perl -w test.pl 2>&1 1>&3 3>&- | splain 1>&2 3>&- + +Nifty, eh? + +If you want to control warnings on the fly, do something like this. +Make sure you do the C<use> first, or you won't be able to get +at the enable() or disable() methods. + + use diagnostics; # checks entire compilation phase + print "\ntime for 1st bogus diags: SQUAWKINGS\n"; + print BOGUS1 'nada'; + print "done with 1st bogus\n"; + + disable diagnostics; # only turns off runtime warnings + print "\ntime for 2nd bogus: (squelched)\n"; + print BOGUS2 'nada'; + print "done with 2nd bogus\n"; + + enable diagnostics; # turns back on runtime warnings + print "\ntime for 3rd bogus: SQUAWKINGS\n"; + print BOGUS3 'nada'; + print "done with 3rd bogus\n"; + + disable diagnostics; + print "\ntime for 4th bogus: (squelched)\n"; + print BOGUS4 'nada'; + print "done with 4th bogus\n"; + +=head1 INTERNALS + +Diagnostic messages derive from the F<perldiag.pod> file when available at +runtime. Otherwise, they may be embedded in the file itself when the +splain package is built. See the F<Makefile> for details. + +If an extant $SIG{__WARN__} handler is discovered, it will continue +to be honored, but only after the diagnostics::splainthis() function +(the module's $SIG{__WARN__} interceptor) has had its way with your +warnings. + +There is a $diagnostics::DEBUG variable you may set if you're desperately +curious what sorts of things are being intercepted. + + BEGIN { $diagnostics::DEBUG = 1 } + + +=head1 BUGS + +Not being able to say "no diagnostics" is annoying, but may not be +insurmountable. + +The C<-pretty> directive is called too late to affect matters. +You have to do this instead, and I<before> you load the module. + + BEGIN { $diagnostics::PRETTY = 1 } + +I could start up faster by delaying compilation until it should be +needed, but this gets a "panic: top_level" when using the pragma form +in Perl 5.001e. + +While it's true that this documentation is somewhat subserious, if you use +a program named I<splain>, you should expect a bit of whimsy. + +=head1 AUTHOR + +Tom Christiansen <F<tchrist@mox.perl.com>>, 25 June 1995. + +=cut + +use strict; +use 5.009001; +use Carp; +$Carp::Internal{__PACKAGE__.""}++; + +our $VERSION = 1.17; +our $DEBUG; +our $VERBOSE; +our $PRETTY; +our $TRACEONLY = 0; +our $WARNTRACE = 0; + +use Config; +my($privlib, $archlib) = @Config{qw(privlibexp archlibexp)}; +if ($^O eq 'VMS') { + require VMS::Filespec; + $privlib = VMS::Filespec::unixify($privlib); + $archlib = VMS::Filespec::unixify($archlib); +} +my @trypod = ( + "$archlib/pod/perldiag.pod", + "$privlib/pod/perldiag-$Config{version}.pod", + "$privlib/pod/perldiag.pod", + "$archlib/pods/perldiag.pod", + "$privlib/pods/perldiag-$Config{version}.pod", + "$privlib/pods/perldiag.pod", + ); +# handy for development testing of new warnings etc +unshift @trypod, "./pod/perldiag.pod" if -e "pod/perldiag.pod"; +(my $PODFILE) = ((grep { -e } @trypod), $trypod[$#trypod])[0]; + +if ($^O eq 'MacOS') { + # just updir one from each lib dir, we'll find it ... + ($PODFILE) = grep { -e } map { "$_:pod:perldiag.pod" } @INC; +} + + +$DEBUG ||= 0; +my $WHOAMI = ref bless []; # nobody's business, prolly not even mine + +local $| = 1; +my $_; + +my $standalone; +my(%HTML_2_Troff, %HTML_2_Latin_1, %HTML_2_ASCII_7); + +CONFIG: { + our $opt_p = our $opt_d = our $opt_v = our $opt_f = ''; + + unless (caller) { + $standalone++; + require Getopt::Std; + Getopt::Std::getopts('pdvf:') + or die "Usage: $0 [-v] [-p] [-f splainpod]"; + $PODFILE = $opt_f if $opt_f; + $DEBUG = 2 if $opt_d; + $VERBOSE = $opt_v; + $PRETTY = $opt_p; + } + + if (open(POD_DIAG, $PODFILE)) { + warn "Happy happy podfile from real $PODFILE\n" if $DEBUG; + last CONFIG; + } + + if (caller) { + INCPATH: { + for my $file ( (map { "$_/$WHOAMI.pm" } @INC), $0) { + warn "Checking $file\n" if $DEBUG; + if (open(POD_DIAG, $file)) { + while (<POD_DIAG>) { + next unless + /^__END__\s*# wish diag dbase were more accessible/; + print STDERR "podfile is $file\n" if $DEBUG; + last INCPATH; + } + } + } + } + } else { + print STDERR "podfile is <DATA>\n" if $DEBUG; + *POD_DIAG = *main::DATA; + } +} +if (eof(POD_DIAG)) { + die "couldn't find diagnostic data in $PODFILE @INC $0"; +} + + +%HTML_2_Troff = ( + 'amp' => '&', # ampersand + 'lt' => '<', # left chevron, less-than + 'gt' => '>', # right chevron, greater-than + 'quot' => '"', # double quote + + "Aacute" => "A\\*'", # capital A, acute accent + # etc + +); + +%HTML_2_Latin_1 = ( + 'amp' => '&', # ampersand + 'lt' => '<', # left chevron, less-than + 'gt' => '>', # right chevron, greater-than + 'quot' => '"', # double quote + + "Aacute" => "\xC1" # capital A, acute accent + + # etc +); + +%HTML_2_ASCII_7 = ( + 'amp' => '&', # ampersand + 'lt' => '<', # left chevron, less-than + 'gt' => '>', # right chevron, greater-than + 'quot' => '"', # double quote + + "Aacute" => "A" # capital A, acute accent + # etc +); + +our %HTML_Escapes; +*HTML_Escapes = do { + if ($standalone) { + $PRETTY ? \%HTML_2_Latin_1 : \%HTML_2_ASCII_7; + } else { + \%HTML_2_Latin_1; + } +}; + +*THITHER = $standalone ? *STDOUT : *STDERR; + +my %transfmt = (); +my $transmo = <<EOFUNC; +sub transmo { + #local \$^W = 0; # recursive warnings we do NOT need! + study; +EOFUNC + +my %msg; +{ + print STDERR "FINISHING COMPILATION for $_\n" if $DEBUG; + local $/ = ''; + my $header; + my $for_item; + while (<POD_DIAG>) { + + unescape(); + if ($PRETTY) { + sub noop { return $_[0] } # spensive for a noop + sub bold { my $str =$_[0]; $str =~ s/(.)/$1\b$1/g; return $str; } + sub italic { my $str = $_[0]; $str =~ s/(.)/_\b$1/g; return $str; } + s/C<<< (.*?) >>>|C<< (.*?) >>|[BC]<(.*?)>/bold($+)/ges; + s/[LIF]<(.*?)>/italic($1)/ges; + } else { + s/C<<< (.*?) >>>|C<< (.*?) >>|[BC]<(.*?)>/$+/gs; + s/[LIF]<(.*?)>/$1/gs; + } + unless (/^=/) { + if (defined $header) { + if ( $header eq 'DESCRIPTION' && + ( /Optional warnings are enabled/ + || /Some of these messages are generic./ + ) ) + { + next; + } + s/^/ /gm; + $msg{$header} .= $_; + undef $for_item; + } + next; + } + unless ( s/=item (.*?)\s*\z//) { + + if ( s/=head1\sDESCRIPTION//) { + $msg{$header = 'DESCRIPTION'} = ''; + undef $for_item; + } + elsif( s/^=for\s+diagnostics\s*\n(.*?)\s*\z// ) { + $for_item = $1; + } + next; + } + + if( $for_item ) { $header = $for_item; undef $for_item } + else { + $header = $1; + while( $header =~ /[;,]\z/ ) { + <POD_DIAG> =~ /^\s*(.*?)\s*\z/; + $header .= ' '.$1; + } + } + + # strip formatting directives from =item line + $header =~ s/[A-Z]<(.*?)>/$1/g; + + my @toks = split( /(%l?[dx]|%c|%(?:\.\d+)?s)/, $header ); + if (@toks > 1) { + my $conlen = 0; + for my $i (0..$#toks){ + if( $i % 2 ){ + if( $toks[$i] eq '%c' ){ + $toks[$i] = '.'; + } elsif( $toks[$i] eq '%d' ){ + $toks[$i] = '\d+'; + } elsif( $toks[$i] eq '%s' ){ + $toks[$i] = $i == $#toks ? '.*' : '.*?'; + } elsif( $toks[$i] =~ '%.(\d+)s' ){ + $toks[$i] = ".{$1}"; + } elsif( $toks[$i] =~ '^%l*x$' ){ + $toks[$i] = '[\da-f]+'; + } + } elsif( length( $toks[$i] ) ){ + $toks[$i] = quotemeta $toks[$i]; + $conlen += length( $toks[$i] ); + } + } + my $lhs = join( '', @toks ); + $transfmt{$header}{pat} = + " s{^$lhs}\n {\Q$header\E}s\n\t&& return 1;\n"; + $transfmt{$header}{len} = $conlen; + } else { + $transfmt{$header}{pat} = + " m{^\Q$header\E} && return 1;\n"; + $transfmt{$header}{len} = length( $header ); + } + + print STDERR "$WHOAMI: Duplicate entry: \"$header\"\n" + if $msg{$header}; + + $msg{$header} = ''; + } + + + close POD_DIAG unless *main::DATA eq *POD_DIAG; + + die "No diagnostics?" unless %msg; + + # Apply patterns in order of decreasing sum of lengths of fixed parts + # Seems the best way of hitting the right one. + for my $hdr ( sort { $transfmt{$b}{len} <=> $transfmt{$a}{len} } + keys %transfmt ){ + $transmo .= $transfmt{$hdr}{pat}; + } + $transmo .= " return 0;\n}\n"; + print STDERR $transmo if $DEBUG; + eval $transmo; + die $@ if $@; +} + +if ($standalone) { + if (!@ARGV and -t STDIN) { print STDERR "$0: Reading from STDIN\n" } + while (defined (my $error = <>)) { + splainthis($error) || print THITHER $error; + } + exit; +} + +my $olddie; +my $oldwarn; + +sub import { + shift; + $^W = 1; # yup, clobbered the global variable; + # tough, if you want diags, you want diags. + return if defined $SIG{__WARN__} && ($SIG{__WARN__} eq \&warn_trap); + + for (@_) { + + /^-d(ebug)?$/ && do { + $DEBUG++; + next; + }; + + /^-v(erbose)?$/ && do { + $VERBOSE++; + next; + }; + + /^-p(retty)?$/ && do { + print STDERR "$0: I'm afraid it's too late for prettiness.\n"; + $PRETTY++; + next; + }; + # matches trace and traceonly for legacy doc mixup reasons + /^-t(race(only)?)?$/ && do { + $TRACEONLY++; + next; + }; + /^-w(arntrace)?$/ && do { + $WARNTRACE++; + next; + }; + + warn "Unknown flag: $_"; + } + + $oldwarn = $SIG{__WARN__}; + $olddie = $SIG{__DIE__}; + $SIG{__WARN__} = \&warn_trap; + $SIG{__DIE__} = \&death_trap; +} + +sub enable { &import } + +sub disable { + shift; + return unless $SIG{__WARN__} eq \&warn_trap; + $SIG{__WARN__} = $oldwarn || ''; + $SIG{__DIE__} = $olddie || ''; +} + +sub warn_trap { + my $warning = $_[0]; + if (caller eq $WHOAMI or !splainthis($warning)) { + if ($WARNTRACE) { + print STDERR Carp::longmess($warning); + } else { + print STDERR $warning; + } + } + goto &$oldwarn if defined $oldwarn and $oldwarn and $oldwarn ne \&warn_trap; +}; + +sub death_trap { + my $exception = $_[0]; + + # See if we are coming from anywhere within an eval. If so we don't + # want to explain the exception because it's going to get caught. + my $in_eval = 0; + my $i = 0; + while (my $caller = (caller($i++))[3]) { + if ($caller eq '(eval)') { + $in_eval = 1; + last; + } + } + + splainthis($exception) unless $in_eval; + if (caller eq $WHOAMI) { print STDERR "INTERNAL EXCEPTION: $exception"; } + &$olddie if defined $olddie and $olddie and $olddie ne \&death_trap; + + return if $in_eval; + + # We don't want to unset these if we're coming from an eval because + # then we've turned off diagnostics. + + # Switch off our die/warn handlers so we don't wind up in our own + # traps. + $SIG{__DIE__} = $SIG{__WARN__} = ''; + + # Have carp skip over death_trap() when showing the stack trace. + local($Carp::CarpLevel) = 1; + + confess "Uncaught exception from user code:\n\t$exception"; + # up we go; where we stop, nobody knows, but i think we die now + # but i'm deeply afraid of the &$olddie guy reraising and us getting + # into an indirect recursion loop +}; + +my %exact_duplicate; +my %old_diag; +my $count; +my $wantspace; +sub splainthis { + return 0 if $TRACEONLY; + $_ = shift; + local $\; + local $!; + ### &finish_compilation unless %msg; + s/\.?\n+$//; + my $orig = $_; + # return unless defined; + + # get rid of the where-are-we-in-input part + s/, <.*?> (?:line|chunk).*$//; + + # Discard 1st " at <file> line <no>" and all text beyond + # but be aware of messsages containing " at this-or-that" + my $real = 0; + my @secs = split( / at / ); + return unless @secs; + $_ = $secs[0]; + for my $i ( 1..$#secs ){ + if( $secs[$i] =~ /.+? (?:line|chunk) \d+/ ){ + $real = 1; + last; + } else { + $_ .= ' at ' . $secs[$i]; + } + } + + # remove parenthesis occurring at the end of some messages + s/^\((.*)\)$/$1/; + + if ($exact_duplicate{$orig}++) { + return &transmo; + } else { + return 0 unless &transmo; + } + + $orig = shorten($orig); + if ($old_diag{$_}) { + autodescribe(); + print THITHER "$orig (#$old_diag{$_})\n"; + $wantspace = 1; + } else { + autodescribe(); + $old_diag{$_} = ++$count; + print THITHER "\n" if $wantspace; + $wantspace = 0; + print THITHER "$orig (#$old_diag{$_})\n"; + if ($msg{$_}) { + print THITHER $msg{$_}; + } else { + if (0 and $standalone) { + print THITHER " **** Error #$old_diag{$_} ", + ($real ? "is" : "appears to be"), + " an unknown diagnostic message.\n\n"; + } + return 0; + } + } + return 1; +} + +sub autodescribe { + if ($VERBOSE and not $count) { + print THITHER &{$PRETTY ? \&bold : \&noop}("DESCRIPTION OF DIAGNOSTICS"), + "\n$msg{DESCRIPTION}\n"; + } +} + +sub unescape { + s { + E< + ( [A-Za-z]+ ) + > + } { + do { + exists $HTML_Escapes{$1} + ? do { $HTML_Escapes{$1} } + : do { + warn "Unknown escape: E<$1> in $_"; + "E<$1>"; + } + } + }egx; +} + +sub shorten { + my $line = $_[0]; + if (length($line) > 79 and index($line, "\n") == -1) { + my $space_place = rindex($line, ' ', 79); + if ($space_place != -1) { + substr($line, $space_place, 1) = "\n\t"; + } + } + return $line; +} + + +1 unless $standalone; # or it'll complain about itself +__END__ # wish diag dbase were more accessible |