JezK
Edit File: Carp.pm
package Carp; { use 5.006; } use strict; use warnings; BEGIN { # Very old versions of warnings.pm load Carp. This can go wrong due # to the circular dependency. If warnings is invoked before Carp, # then warnings starts by loading Carp, then Carp (above) tries to # invoke warnings, and gets nothing because warnings is in the process # of loading and hasn't defined its import method yet. If we were # only turning on warnings ("use warnings" above) this wouldn't be too # bad, because Carp would just gets the state of the -w switch and so # might not get some warnings that it wanted. The real problem is # that we then want to turn off Unicode warnings, but "no warnings # 'utf8'" won't be effective if we're in this circular-dependency # situation. So, if warnings.pm is an affected version, we turn # off all warnings ourselves by directly setting ${^WARNING_BITS}. # On unaffected versions, we turn off just Unicode warnings, via # the proper API. if(!defined($warnings::VERSION) || eval($warnings::VERSION) < 1.06) { ${^WARNING_BITS} = ""; } else { "warnings"->unimport("utf8"); } } sub _fetch_sub { # fetch sub without autovivifying my($pack, $sub) = @_; $pack .= '::'; # only works with top-level packages return unless exists($::{$pack}); for ($::{$pack}) { return unless ref \$_ eq 'GLOB' && *$_{HASH} && exists $$_{$sub}; for ($$_{$sub}) { return ref \$_ eq 'GLOB' ? *$_{CODE} : undef } } } # UTF8_REGEXP_PROBLEM is a compile-time constant indicating whether Carp # must avoid applying a regular expression to an upgraded (is_utf8) # string. There are multiple problems, on different Perl versions, # that require this to be avoided. All versions prior to 5.13.8 will # load utf8_heavy.pl for the swash system, even if the regexp doesn't # use character classes. Perl 5.6 and Perls [5.11.2, 5.13.11) exhibit # specific problems when Carp is being invoked in the aftermath of a # syntax error. BEGIN { if("$]" < 5.013011) { *UTF8_REGEXP_PROBLEM = sub () { 1 }; } else { *UTF8_REGEXP_PROBLEM = sub () { 0 }; } } # is_utf8() is essentially the utf8::is_utf8() function, which indicates # whether a string is represented in the upgraded form (using UTF-8 # internally). As utf8::is_utf8() is only available from Perl 5.8 # onwards, extra effort is required here to make it work on Perl 5.6. BEGIN { if(defined(my $sub = _fetch_sub utf8 => 'is_utf8')) { *is_utf8 = $sub; } else { # black magic for perl 5.6 *is_utf8 = sub { unpack("C", "\xaa".$_[0]) != 170 }; } } # The downgrade() function defined here is to be used for attempts to # downgrade where it is acceptable to fail. It must be called with a # second argument that is a true value. BEGIN { if(defined(my $sub = _fetch_sub utf8 => 'downgrade')) { *downgrade = \&{"utf8::downgrade"}; } else { *downgrade = sub { my $r = ""; my $l = length($_[0]); for(my $i = 0; $i != $l; $i++) { my $o = ord(substr($_[0], $i, 1)); return if $o > 255; $r .= chr($o); } $_[0] = $r; }; } } # is_safe_printable_codepoint() indicates whether a character, specified # by integer codepoint, is OK to output literally in a trace. Generally # this is if it is a printable character in the ancestral character set # (ASCII or EBCDIC). This is used on some Perls in situations where a # regexp can't be used. BEGIN { *is_safe_printable_codepoint = "$]" >= 5.007_003 ? eval(q(sub ($) { my $u = utf8::native_to_unicode($_[0]); $u >= 0x20 && $u <= 0x7e; })) : ord("A") == 65 ? sub ($) { $_[0] >= 0x20 && $_[0] <= 0x7e } : sub ($) { # Early EBCDIC # 3 EBCDIC code pages supported then; all controls but one # are the code points below SPACE. The other one is 0x5F on # POSIX-BC; FF on the other two. # FIXME: there are plenty of unprintable codepoints other # than those that this code and the comment above identifies # as "controls". $_[0] >= ord(" ") && $_[0] <= 0xff && $_[0] != (ord ("^") == 106 ? 0x5f : 0xff); } ; } sub _univ_mod_loaded { return 0 unless exists($::{"UNIVERSAL::"}); for ($::{"UNIVERSAL::"}) { return 0 unless ref \$_ eq "GLOB" && *$_{HASH} && exists $$_{"$_[0]::"}; for ($$_{"$_[0]::"}) { return 0 unless ref \$_ eq "GLOB" && *$_{HASH} && exists $$_{"VERSION"}; for ($$_{"VERSION"}) { return 0 unless ref \$_ eq "GLOB"; return ${*$_{SCALAR}}; } } } } # _maybe_isa() is usually the UNIVERSAL::isa function. We have to avoid # the latter if the UNIVERSAL::isa module has been loaded, to avoid infi- # nite recursion; in that case _maybe_isa simply returns true. my $isa; BEGIN { if (_univ_mod_loaded('isa')) { *_maybe_isa = sub { 1 } } else { # Since we have already done the check, record $isa for use below # when defining _StrVal. *_maybe_isa = $isa = _fetch_sub(UNIVERSAL => "isa"); } } # We need an overload::StrVal or equivalent function, but we must avoid # loading any modules on demand, as Carp is used from __DIE__ handlers and # may be invoked after a syntax error. # We can copy recent implementations of overload::StrVal and use # overloading.pm, which is the fastest implementation, so long as # overloading is available. If it is not available, we use our own pure- # Perl StrVal. We never actually use overload::StrVal, for various rea- # sons described below. # overload versions are as follows: # undef-1.00 (up to perl 5.8.0) uses bless (avoid!) # 1.01-1.17 (perl 5.8.1 to 5.14) uses Scalar::Util # 1.18+ (perl 5.16+) uses overloading # The ancient 'bless' implementation (that inspires our pure-Perl version) # blesses unblessed references and must be avoided. Those using # Scalar::Util use refaddr, possibly the pure-Perl implementation, which # has the same blessing bug, and must be avoided. Also, Scalar::Util is # loaded on demand. Since we avoid the Scalar::Util implementations, we # end up having to implement our own overloading.pm-based version for perl # 5.10.1 to 5.14. Since it also works just as well in more recent ver- # sions, we use it there, too. BEGIN { if (eval { require "overloading.pm" }) { *_StrVal = eval 'sub { no overloading; "$_[0]" }' } else { # Work around the UNIVERSAL::can/isa modules to avoid recursion. # _mycan is either UNIVERSAL::can, or, in the presence of an # override, overload::mycan. *_mycan = _univ_mod_loaded('can') ? do { require "overload.pm"; _fetch_sub overload => 'mycan' } : \&UNIVERSAL::can; # _blessed is either UNIVERAL::isa(...), or, in the presence of an # override, a hideous, but fairly reliable, workaround. *_blessed = $isa ? sub { &$isa($_[0], "UNIVERSAL") } : sub { my $probe = "UNIVERSAL::Carp_probe_" . rand; no strict 'refs'; local *$probe = sub { "unlikely string" }; local $@; local $SIG{__DIE__} = sub{}; (eval { $_[0]->$probe } || '') eq 'unlikely string' }; *_StrVal = sub { my $pack = ref $_[0]; # Perl's overload mechanism uses the presence of a special # "method" named "((" or "()" to signal it is in effect. # This test seeks to see if it has been set up. "((" post- # dates overloading.pm, so we can skip it. return "$_[0]" unless _mycan($pack, "()"); # Even at this point, the invocant may not be blessed, so # check for that. return "$_[0]" if not _blessed($_[0]); bless $_[0], "Carp"; my $str = "$_[0]"; bless $_[0], $pack; $pack . substr $str, index $str, "="; } } } our $VERSION = '1.52'; $VERSION =~ tr/_//d; our $MaxEvalLen = 0; our $Verbose = 0; our $CarpLevel = 0; our $MaxArgLen = 64; # How much of each argument to print. 0 = all. our $MaxArgNums = 8; # How many arguments to print. 0 = all. our $RefArgFormatter = undef; # allow caller to format reference arguments require Exporter; our @ISA = ('Exporter'); our @EXPORT = qw(confess croak carp); our @EXPORT_OK = qw(cluck verbose longmess shortmess); our @EXPORT_FAIL = qw(verbose); # hook to enable verbose mode # The members of %Internal are packages that are internal to perl. # Carp will not report errors from within these packages if it # can. The members of %CarpInternal are internal to Perl's warning # system. Carp will not report errors from within these packages # either, and will not report calls *to* these packages for carp and # croak. They replace $CarpLevel, which is deprecated. The # $Max(EvalLen|(Arg(Len|Nums)) variables are used to specify how the eval # text and function arguments should be formatted when printed. our %CarpInternal; our %Internal; # disable these by default, so they can live w/o require Carp $CarpInternal{Carp}++; $CarpInternal{warnings}++; $Internal{Exporter}++; $Internal{'Exporter::Heavy'}++; # if the caller specifies verbose usage ("perl -MCarp=verbose script.pl") # then the following method will be called by the Exporter which knows # to do this thanks to @EXPORT_FAIL, above. $_[1] will contain the word # 'verbose'. sub export_fail { shift; $Verbose = shift if $_[0] eq 'verbose'; @_ } sub _cgc { no strict 'refs'; return \&{"CORE::GLOBAL::caller"} if defined &{"CORE::GLOBAL::caller"}; return; } sub longmess { local($!, $^E); # Icky backwards compatibility wrapper. :-( # # The story is that the original implementation hard-coded the # number of call levels to go back, so calls to longmess were off # by one. Other code began calling longmess and expecting this # behaviour, so the replacement has to emulate that behaviour. my $cgc = _cgc(); my $call_pack = $cgc ? $cgc->() : caller(); if ( $Internal{$call_pack} or $CarpInternal{$call_pack} ) { return longmess_heavy(@_); } else { local $CarpLevel = $CarpLevel + 1; return longmess_heavy(@_); } } our @CARP_NOT; sub shortmess { local($!, $^E); my $cgc = _cgc(); # Icky backwards compatibility wrapper. :-( local @CARP_NOT = scalar( $cgc ? $cgc->() : caller() ); shortmess_heavy(@_); } sub croak { die shortmess @_ } sub confess { die longmess @_ } sub carp { warn shortmess @_ } sub cluck { warn longmess @_ } BEGIN { if("$]" >= 5.015002 || ("$]" >= 5.014002 && "$]" < 5.015) || ("$]" >= 5.012005 && "$]" < 5.013)) { *CALLER_OVERRIDE_CHECK_OK = sub () { 1 }; } else { *CALLER_OVERRIDE_CHECK_OK = sub () { 0 }; } } sub caller_info { my $i = shift(@_) + 1; my %call_info; my $cgc = _cgc(); { # Some things override caller() but forget to implement the # @DB::args part of it, which we need. We check for this by # pre-populating @DB::args with a sentinel which no-one else # has the address of, so that we can detect whether @DB::args # has been properly populated. However, on earlier versions # of perl this check tickles a bug in CORE::caller() which # leaks memory. So we only check on fixed perls. @DB::args = \$i if CALLER_OVERRIDE_CHECK_OK; package DB; @call_info{ qw(pack file line sub has_args wantarray evaltext is_require) } = $cgc ? $cgc->($i) : caller($i); } unless ( defined $call_info{file} ) { return (); } my $sub_name = Carp::get_subname( \%call_info ); if ( $call_info{has_args} ) { # Guard our serialization of the stack from stack refcounting bugs # NOTE this is NOT a complete solution, we cannot 100% guard against # these bugs. However in many cases Perl *is* capable of detecting # them and throws an error when it does. Unfortunately serializing # the arguments on the stack is a perfect way of finding these bugs, # even when they would not affect normal program flow that did not # poke around inside the stack. Inside of Carp.pm it makes little # sense reporting these bugs, as Carp's job is to report the callers # errors, not the ones it might happen to tickle while doing so. # See: https://rt.perl.org/Public/Bug/Display.html?id=131046 # and: https://rt.perl.org/Public/Bug/Display.html?id=52610 # for more details and discussion. - Yves my @args = map { my $arg; local $@= $@; eval { $arg = $_; 1; } or do { $arg = '** argument not available anymore **'; }; $arg; } @DB::args; if (CALLER_OVERRIDE_CHECK_OK && @args == 1 && ref $args[0] eq ref \$i && $args[0] == \$i ) { @args = (); # Don't let anyone see the address of $i local $@; my $where = eval { my $func = $cgc or return ''; my $gv = (_fetch_sub B => 'svref_2object' or return '') ->($func)->GV; my $package = $gv->STASH->NAME; my $subname = $gv->NAME; return unless defined $package && defined $subname; # returning CORE::GLOBAL::caller isn't useful for tracing the cause: return if $package eq 'CORE::GLOBAL' && $subname eq 'caller'; " in &${package}::$subname"; } || ''; @args = "** Incomplete caller override detected$where; \@DB::args were not set **"; } else { my $overflow; if ( $MaxArgNums and @args > $MaxArgNums ) { # More than we want to show? $#args = $MaxArgNums - 1; $overflow = 1; } @args = map { Carp::format_arg($_) } @args; if ($overflow) { 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. our $in_recurse; sub format_arg { my $arg = shift; if ( my $pack= ref($arg) ) { # legitimate, let's not leak it. if (!$in_recurse && _maybe_isa( $arg, 'UNIVERSAL' ) && do { local $@; local $in_recurse = 1; local $SIG{__DIE__} = sub{}; eval {$arg->can('CARP_TRACE') } }) { return $arg->CARP_TRACE(); } elsif (!$in_recurse && defined($RefArgFormatter) && do { local $@; local $in_recurse = 1; local $SIG{__DIE__} = sub{}; eval {$arg = $RefArgFormatter->($arg); 1} }) { return $arg; } else { # Argument may be blessed into a class with overloading, and so # might have an overloaded stringification. We don't want to # risk getting the overloaded stringification, so we need to # use _StrVal, our overload::StrVal()-equivalent. return _StrVal $arg; } } return "undef" if !defined($arg); downgrade($arg, 1); return $arg if !(UTF8_REGEXP_PROBLEM && is_utf8($arg)) && $arg =~ /\A-?[0-9]+(?:\.[0-9]*)?(?:[eE][-+]?[0-9]+)?\z/; my $suffix = ""; if ( 2 < $MaxArgLen and $MaxArgLen < length($arg) ) { substr ( $arg, $MaxArgLen - 3 ) = ""; $suffix = "..."; } if(UTF8_REGEXP_PROBLEM && is_utf8($arg)) { for(my $i = length($arg); $i--; ) { my $c = substr($arg, $i, 1); my $x = substr($arg, 0, 0); # work around bug on Perl 5.8.{1,2} if($c eq "\"" || $c eq "\\" || $c eq "\$" || $c eq "\@") { substr $arg, $i, 0, "\\"; next; } my $o = ord($c); substr $arg, $i, 1, sprintf("\\x{%x}", $o) unless is_safe_printable_codepoint($o); } } else { $arg =~ s/([\"\\\$\@])/\\$1/g; # This is all the ASCII printables spelled-out. It is portable to all # Perl versions and platforms (such as EBCDIC). There are other more # compact ways to do this, but may not work everywhere every version. $arg =~ s/([^ !"#\$\%\&'()*+,\-.\/0123456789:;<=>?\@ABCDEFGHIJKLMNOPQRSTUVWXYZ\[\\\]^_`abcdefghijklmnopqrstuvwxyz\{|}~])/sprintf("\\x{%x}",ord($1))/eg; } downgrade($arg, 1); return "\"".$arg."\"".$suffix; } sub Regexp::CARP_TRACE { my $arg = "$_[0]"; downgrade($arg, 1); if(UTF8_REGEXP_PROBLEM && is_utf8($arg)) { for(my $i = length($arg); $i--; ) { my $o = ord(substr($arg, $i, 1)); my $x = substr($arg, 0, 0); # work around bug on Perl 5.8.{1,2} substr $arg, $i, 1, sprintf("\\x{%x}", $o) unless is_safe_printable_codepoint($o); } } else { # See comment in format_arg() about this same regex. $arg =~ s/([^ !"#\$\%\&'()*+,\-.\/0123456789:;<=>?\@ABCDEFGHIJKLMNOPQRSTUVWXYZ\[\\\]^_`abcdefghijklmnopqrstuvwxyz\{|}~])/sprintf("\\x{%x}",ord($1))/eg; } downgrade($arg, 1); my $suffix = ""; if($arg =~ /\A\(\?\^?([a-z]*)(?:-[a-z]*)?:(.*)\)\z/s) { ($suffix, $arg) = ($1, $2); } if ( 2 < $MaxArgLen and $MaxArgLen < length($arg) ) { substr ( $arg, $MaxArgLen - 3 ) = ""; $suffix = "...".$suffix; } return "qr($arg)$suffix"; } # 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 ) . "'"; } } # this can happen on older perls when the sub (or the stash containing it) # has been deleted if ( !defined( $info->{sub} ) ) { return '__ANON__::__ANON__'; } 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 = $CarpLevel; { ++$i; my $cgc = _cgc(); my @caller = $cgc ? $cgc->($i) : caller($i); my $pkg = $caller[0]; unless ( defined($pkg) ) { # This *shouldn't* happen. if (%Internal) { local %Internal; $i = long_error_loc(); last; } elsif (defined $caller[2]) { # this can happen when the stash has been deleted # in that case, just assume that it's a reasonable place to # stop (the file and line data will still be intact in any # case) - the only issue is that we can't detect if the # deleted package was internal (so don't do that then) # -doy redo unless 0 > --$lvl; last; } else { return 2; } } redo if $CarpInternal{$pkg}; redo unless 0 > --$lvl; redo if $Internal{$pkg}; } return $i - 1; } sub longmess_heavy { if ( ref( $_[0] ) ) { # don't break references as exceptions return wantarray ? @_ : $_[0]; } my $i = long_error_loc(); return ret_backtrace( $i, @_ ); } BEGIN { if("$]" >= 5.017004) { # The LAST_FH constant is a reference to the variable. $Carp::{LAST_FH} = \eval '\${^LAST_FH}'; } else { eval '*LAST_FH = sub () { 0 }'; } } # 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 &threads::tid ) { my $tid = threads->tid; $tid_msg = " thread $tid" if $tid; } my %i = caller_info($i); $mess = "$err at $i{file} line $i{line}$tid_msg"; if( $. ) { # Use ${^LAST_FH} if available. if (LAST_FH) { if (${+LAST_FH}) { $mess .= sprintf ", <%s> %s %d", *${+LAST_FH}{NAME}, ($/ eq "\n" ? "line" : "chunk"), $. } } else { local $@ = ''; local $SIG{__DIE__}; eval { CORE::die; }; if($@ =~ /^Died at .*(, <.*?> (?:line|chunk) \d+).$/ ) { $mess .= $1; } } } $mess .= "\.\n"; while ( my %i = caller_info( ++$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 $err = join '', @error; $i++; my $tid_msg = ''; if ( defined &threads::tid ) { my $tid = threads->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 { # You have to create your (hash)ref out here, rather than defaulting it # inside trusts *on a lexical*, as you want it to persist across calls. # (You can default it on $_[2], but that gets messy) my $cache = {}; my $i = 1; my $lvl = $CarpLevel; { my $cgc = _cgc(); my $called = $cgc ? $cgc->($i) : caller($i); $i++; my $caller = $cgc ? $cgc->($i) : caller($i); if (!defined($caller)) { my @caller = $cgc ? $cgc->($i) : caller($i); if (@caller) { # if there's no package but there is other caller info, then # the package has been deleted - treat this as a valid package # in this case redo if defined($called) && $CarpInternal{$called}; redo unless 0 > --$lvl; last; } else { return 0; } } redo if $Internal{$caller}; redo if $CarpInternal{$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'; my $stash = \%{"$class\::"}; for my $var (qw/ CARP_NOT ISA /) { # Don't try using the variable until we know it exists, # to avoid polluting the caller's namespace. if ( $stash->{$var} && ref \$stash->{$var} eq 'GLOB' && *{$stash->{$var}}{ARRAY} && @{$stash->{$var}} ) { return @{$stash->{$var}} } } return; } if(!defined($warnings::VERSION) || do { no warnings "numeric"; $warnings::VERSION < 1.03 }) { # Very old versions of warnings.pm import from Carp. This can go # wrong due to the circular dependency. If Carp is invoked before # warnings, then Carp starts by loading warnings, then warnings # tries to import from Carp, and gets nothing because Carp is in # the process of loading and hasn't defined its import method yet. # So we work around that by manually exporting to warnings here. no strict "refs"; *{"warnings::$_"} = \&$_ foreach @EXPORT; } 1; __END__