diff options
Diffstat (limited to 'pidl/lib/Parse/Yapp')
| -rw-r--r-- | pidl/lib/Parse/Yapp/Driver.pm | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/pidl/lib/Parse/Yapp/Driver.pm b/pidl/lib/Parse/Yapp/Driver.pm new file mode 100644 index 0000000000..d0dcbf54eb --- /dev/null +++ b/pidl/lib/Parse/Yapp/Driver.pm @@ -0,0 +1,471 @@ +# +# Module Parse::Yapp::Driver +# +# This module is part of the Parse::Yapp package available on your +# nearest CPAN +# +# Any use of this module in a standalone parser make the included +# text under the same copyright as the Parse::Yapp module itself. +# +# This notice should remain unchanged. +# +# (c) Copyright 1998-2001 Francois Desarmenien, all rights reserved. +# (see the pod text in Parse::Yapp module for use and distribution rights) +# + +package Parse::Yapp::Driver; + +require 5.004; + +use strict; + +use vars qw ( $VERSION $COMPATIBLE $FILENAME ); + +$VERSION = '1.05'; +$COMPATIBLE = '0.07'; +$FILENAME=__FILE__; + +use Carp; + +#Known parameters, all starting with YY (leading YY will be discarded) +my(%params)=(YYLEX => 'CODE', 'YYERROR' => 'CODE', YYVERSION => '', + YYRULES => 'ARRAY', YYSTATES => 'ARRAY', YYDEBUG => ''); +#Mandatory parameters +my(@params)=('LEX','RULES','STATES'); + +sub new { + my($class)=shift; + my($errst,$nberr,$token,$value,$check,$dotpos); + my($self)={ ERROR => \&_Error, + ERRST => \$errst, + NBERR => \$nberr, + TOKEN => \$token, + VALUE => \$value, + DOTPOS => \$dotpos, + STACK => [], + DEBUG => 0, + CHECK => \$check }; + + _CheckParams( [], \%params, \@_, $self ); + + exists($$self{VERSION}) + and $$self{VERSION} < $COMPATIBLE + and croak "Yapp driver version $VERSION ". + "incompatible with version $$self{VERSION}:\n". + "Please recompile parser module."; + + ref($class) + and $class=ref($class); + + bless($self,$class); +} + +sub YYParse { + my($self)=shift; + my($retval); + + _CheckParams( \@params, \%params, \@_, $self ); + + if($$self{DEBUG}) { + _DBLoad(); + $retval = eval '$self->_DBParse()';#Do not create stab entry on compile + $@ and die $@; + } + else { + $retval = $self->_Parse(); + } + $retval +} + +sub YYData { + my($self)=shift; + + exists($$self{USER}) + or $$self{USER}={}; + + $$self{USER}; + +} + +sub YYErrok { + my($self)=shift; + + ${$$self{ERRST}}=0; + undef; +} + +sub YYNberr { + my($self)=shift; + + ${$$self{NBERR}}; +} + +sub YYRecovering { + my($self)=shift; + + ${$$self{ERRST}} != 0; +} + +sub YYAbort { + my($self)=shift; + + ${$$self{CHECK}}='ABORT'; + undef; +} + +sub YYAccept { + my($self)=shift; + + ${$$self{CHECK}}='ACCEPT'; + undef; +} + +sub YYError { + my($self)=shift; + + ${$$self{CHECK}}='ERROR'; + undef; +} + +sub YYSemval { + my($self)=shift; + my($index)= $_[0] - ${$$self{DOTPOS}} - 1; + + $index < 0 + and -$index <= @{$$self{STACK}} + and return $$self{STACK}[$index][1]; + + undef; #Invalid index +} + +sub YYCurtok { + my($self)=shift; + + @_ + and ${$$self{TOKEN}}=$_[0]; + ${$$self{TOKEN}}; +} + +sub YYCurval { + my($self)=shift; + + @_ + and ${$$self{VALUE}}=$_[0]; + ${$$self{VALUE}}; +} + +sub YYExpect { + my($self)=shift; + + keys %{$self->{STATES}[$self->{STACK}[-1][0]]{ACTIONS}} +} + +sub YYLexer { + my($self)=shift; + + $$self{LEX}; +} + + +################# +# Private stuff # +################# + + +sub _CheckParams { + my($mandatory,$checklist,$inarray,$outhash)=@_; + my($prm,$value); + my($prmlst)={}; + + while(($prm,$value)=splice(@$inarray,0,2)) { + $prm=uc($prm); + exists($$checklist{$prm}) + or croak("Unknow parameter '$prm'"); + ref($value) eq $$checklist{$prm} + or croak("Invalid value for parameter '$prm'"); + $prm=unpack('@2A*',$prm); + $$outhash{$prm}=$value; + } + for (@$mandatory) { + exists($$outhash{$_}) + or croak("Missing mandatory parameter '".lc($_)."'"); + } +} + +sub _Error { + print "Parse error.\n"; +} + +sub _DBLoad { + { + no strict 'refs'; + + exists(${__PACKAGE__.'::'}{_DBParse})#Already loaded ? + and return; + } + my($fname)=__FILE__; + my(@drv); + open(DRV,"<$fname") or die "Report this as a BUG: Cannot open $fname"; + while(<DRV>) { + /^\s*sub\s+_Parse\s*{\s*$/ .. /^\s*}\s*#\s*_Parse\s*$/ + and do { + s/^#DBG>//; + push(@drv,$_); + } + } + close(DRV); + + $drv[0]=~s/_P/_DBP/; + eval join('',@drv); +} + +#Note that for loading debugging version of the driver, +#this file will be parsed from 'sub _Parse' up to '}#_Parse' inclusive. +#So, DO NOT remove comment at end of sub !!! +sub _Parse { + my($self)=shift; + + my($rules,$states,$lex,$error) + = @$self{ 'RULES', 'STATES', 'LEX', 'ERROR' }; + my($errstatus,$nberror,$token,$value,$stack,$check,$dotpos) + = @$self{ 'ERRST', 'NBERR', 'TOKEN', 'VALUE', 'STACK', 'CHECK', 'DOTPOS' }; + +#DBG> my($debug)=$$self{DEBUG}; +#DBG> my($dbgerror)=0; + +#DBG> my($ShowCurToken) = sub { +#DBG> my($tok)='>'; +#DBG> for (split('',$$token)) { +#DBG> $tok.= (ord($_) < 32 or ord($_) > 126) +#DBG> ? sprintf('<%02X>',ord($_)) +#DBG> : $_; +#DBG> } +#DBG> $tok.='<'; +#DBG> }; + + $$errstatus=0; + $$nberror=0; + ($$token,$$value)=(undef,undef); + @$stack=( [ 0, undef ] ); + $$check=''; + + while(1) { + my($actions,$act,$stateno); + + $stateno=$$stack[-1][0]; + $actions=$$states[$stateno]; + +#DBG> print STDERR ('-' x 40),"\n"; +#DBG> $debug & 0x2 +#DBG> and print STDERR "In state $stateno:\n"; +#DBG> $debug & 0x08 +#DBG> and print STDERR "Stack:[". +#DBG> join(',',map { $$_[0] } @$stack). +#DBG> "]\n"; + + + if (exists($$actions{ACTIONS})) { + + defined($$token) + or do { + ($$token,$$value)=&$lex($self); +#DBG> $debug & 0x01 +#DBG> and print STDERR "Need token. Got ".&$ShowCurToken."\n"; + }; + + $act= exists($$actions{ACTIONS}{$$token}) + ? $$actions{ACTIONS}{$$token} + : exists($$actions{DEFAULT}) + ? $$actions{DEFAULT} + : undef; + } + else { + $act=$$actions{DEFAULT}; +#DBG> $debug & 0x01 +#DBG> and print STDERR "Don't need token.\n"; + } + + defined($act) + and do { + + $act > 0 + and do { #shift + +#DBG> $debug & 0x04 +#DBG> and print STDERR "Shift and go to state $act.\n"; + + $$errstatus + and do { + --$$errstatus; + +#DBG> $debug & 0x10 +#DBG> and $dbgerror +#DBG> and $$errstatus == 0 +#DBG> and do { +#DBG> print STDERR "**End of Error recovery.\n"; +#DBG> $dbgerror=0; +#DBG> }; + }; + + + push(@$stack,[ $act, $$value ]); + + $$token ne '' #Don't eat the eof + and $$token=$$value=undef; + next; + }; + + #reduce + my($lhs,$len,$code,@sempar,$semval); + ($lhs,$len,$code)=@{$$rules[-$act]}; + +#DBG> $debug & 0x04 +#DBG> and $act +#DBG> and print STDERR "Reduce using rule ".-$act." ($lhs,$len): "; + + $act + or $self->YYAccept(); + + $$dotpos=$len; + + unpack('A1',$lhs) eq '@' #In line rule + and do { + $lhs =~ /^\@[0-9]+\-([0-9]+)$/ + or die "In line rule name '$lhs' ill formed: ". + "report it as a BUG.\n"; + $$dotpos = $1; + }; + + @sempar = $$dotpos + ? map { $$_[1] } @$stack[ -$$dotpos .. -1 ] + : (); + + $semval = $code ? &$code( $self, @sempar ) + : @sempar ? $sempar[0] : undef; + + splice(@$stack,-$len,$len); + + $$check eq 'ACCEPT' + and do { + +#DBG> $debug & 0x04 +#DBG> and print STDERR "Accept.\n"; + + return($semval); + }; + + $$check eq 'ABORT' + and do { + +#DBG> $debug & 0x04 +#DBG> and print STDERR "Abort.\n"; + + return(undef); + + }; + +#DBG> $debug & 0x04 +#DBG> and print STDERR "Back to state $$stack[-1][0], then "; + + $$check eq 'ERROR' + or do { +#DBG> $debug & 0x04 +#DBG> and print STDERR +#DBG> "go to state $$states[$$stack[-1][0]]{GOTOS}{$lhs}.\n"; + +#DBG> $debug & 0x10 +#DBG> and $dbgerror +#DBG> and $$errstatus == 0 +#DBG> and do { +#DBG> print STDERR "**End of Error recovery.\n"; +#DBG> $dbgerror=0; +#DBG> }; + + push(@$stack, + [ $$states[$$stack[-1][0]]{GOTOS}{$lhs}, $semval ]); + $$check=''; + next; + }; + +#DBG> $debug & 0x04 +#DBG> and print STDERR "Forced Error recovery.\n"; + + $$check=''; + + }; + + #Error + $$errstatus + or do { + + $$errstatus = 1; + &$error($self); + $$errstatus # if 0, then YYErrok has been called + or next; # so continue parsing + +#DBG> $debug & 0x10 +#DBG> and do { +#DBG> print STDERR "**Entering Error recovery.\n"; +#DBG> ++$dbgerror; +#DBG> }; + + ++$$nberror; + + }; + + $$errstatus == 3 #The next token is not valid: discard it + and do { + $$token eq '' # End of input: no hope + and do { +#DBG> $debug & 0x10 +#DBG> and print STDERR "**At eof: aborting.\n"; + return(undef); + }; + +#DBG> $debug & 0x10 +#DBG> and print STDERR "**Dicard invalid token ".&$ShowCurToken.".\n"; + + $$token=$$value=undef; + }; + + $$errstatus=3; + + while( @$stack + and ( not exists($$states[$$stack[-1][0]]{ACTIONS}) + or not exists($$states[$$stack[-1][0]]{ACTIONS}{error}) + or $$states[$$stack[-1][0]]{ACTIONS}{error} <= 0)) { + +#DBG> $debug & 0x10 +#DBG> and print STDERR "**Pop state $$stack[-1][0].\n"; + + pop(@$stack); + } + + @$stack + or do { + +#DBG> $debug & 0x10 +#DBG> and print STDERR "**No state left on stack: aborting.\n"; + + return(undef); + }; + + #shift the error token + +#DBG> $debug & 0x10 +#DBG> and print STDERR "**Shift \$error token and go to state ". +#DBG> $$states[$$stack[-1][0]]{ACTIONS}{error}. +#DBG> ".\n"; + + push(@$stack, [ $$states[$$stack[-1][0]]{ACTIONS}{error}, undef ]); + + } + + #never reached + croak("Error in driver logic. Please, report it as a BUG"); + +}#_Parse +#DO NOT remove comment + +1; + |