X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FCarp.pm;h=69d477b486e16c55151d4c529fcbd8e0f179b9e2;hb=0064a8a9866779dceb087452b9bfaa733c51adce;hp=6bac36446a7d61e633ad6da272f95d7e35be4b51;hpb=6ff81951f79dec32e15a779d288c1047f0e4fefb;p=p5sagit%2Fp5-mst-13.2.git diff --git a/lib/Carp.pm b/lib/Carp.pm index 6bac364..69d477b 100644 --- a/lib/Carp.pm +++ b/lib/Carp.pm @@ -1,5 +1,7 @@ package Carp; +our $VERSION = '1.00'; + =head1 NAME carp - warn of errors (from perspective of caller) @@ -35,7 +37,7 @@ and a carp as a cluck across I modules. In other words, force a detailed stack trace to be given. This can be very helpful when trying to understand why, or from where, a warning or error is being generated. -This feature is enabled by 'importing' the non-existant symbol +This feature is enabled by 'importing' the non-existent symbol 'verbose'. You would typically enable it by saying perl -MCarp=verbose script.pl @@ -43,6 +45,12 @@ This feature is enabled by 'importing' the non-existant symbol or by including the string C in the L environment variable. +=head1 BUGS + +The Carp routines don't handle exception objects currently. +If called with a first argument that is a reference, they simply +call die() or warn(), as appropriate. + =cut # This package is heavily used. Be small. Be fast. Be good. @@ -62,6 +70,8 @@ $MaxArgLen = 64; # How much of each argument to print. 0 = all. $MaxArgNums = 8; # How many arguments to print. 0 = all. $Verbose = 0; # If true then make shortmess call longmess instead +$CarpInternal{Carp}++; + require Exporter; @ISA = ('Exporter'); @EXPORT = qw(confess croak carp); @@ -88,97 +98,8 @@ sub export_fail { # each function call on the stack. sub longmess { - 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-' or '^' - s/([\200-\377])/sprintf("M-%c",ord($1)&0177)/eg; - 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 $line\n"; - } - # we don't need to print the actual error message again so we can - # change this to "called" so that the string "$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; + { local $@; require Carp::Heavy; } # XXX fix require to not clear $@? + goto &longmess_heavy; } @@ -189,77 +110,8 @@ sub longmess { # you always get a stack trace sub shortmess { # Short-circuit &longmess if called via multiple packages - goto &longmess if $Verbose; - 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(defined @{"${prevpack}::ISA"}); - - # now we crawl up the calling stack and look at all the packages in - # there. For each package, we look to see if it has an @ISA and then - # we see if our caller features in that list. That would imply that - # our caller is a derived class of that package and its calls can also - # be ignored - while (($pack,$file,$line) = caller($i++)) { - if(defined @{$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(defined @{$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 $msg = "$error at $file line $line\n") =~ 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; + { local $@; require Carp::Heavy; } # XXX fix require to not clear $@? + goto &shortmess_heavy; }