pjs/config/preprocessor.pl

416 строки
10 KiB
Perl
Executable File

#!/usr/bin/perl -w
# -*- Mode: perl; tab-width: 4; indent-tabs-mode: nil; -*-
#
# Preprocessor
# Version 1.0
#
# Copyright (c) 2002 by Ian Hickson
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
use strict;
# takes as arguments the files to process
# defaults to stdin
# output to stdout
my $stack = new stack;
# command line arguments
my @includes;
while ($_ = $ARGV[0], defined($_) && /^-./) {
shift;
last if /^--$/os;
if (/^-D(.*)$/os) {
for ($1) {
if (/^(\w+)=(.*)$/os) {
$stack->define($1, $2);
} elsif (/^(\w+)$/os) {
$stack->define($1, 1);
} else {
die "$0: invalid argument to -D: $_\n";
}
}
} elsif (/^-F(.*)$/os) {
for ($1) {
if (/^(\w+)$/os) {
$stack->filter($1, 1);
} else {
die "$0: invalid argument to -F: $_\n";
}
}
} elsif (/^-I(.*)$/os) {
push(@includes, $1);
} elsif (/^-E$/os) {
foreach (keys %ENV) {
$stack->define($_, $ENV{$_});
}
} else {
die "$0: invalid argument: $_\n";
}
}
unshift(@ARGV, '-') unless @ARGV;
unshift(@ARGV, @includes);
# do the work
foreach (@ARGV) { include($stack, $_); }
exit(0);
########################################################################
package main;
use File::Spec 0.8;
use File::Spec::Unix; # on all platforms, because the #include syntax is unix-based
sub include {
my($stack, $filename) = @_;
if ($filename ne '-') {
$filename = File::Spec->rel2abs($filename, $stack->{'variables'}->{'DIRECTORY'});
my($volume, $directory) = File::Spec->splitpath($filename);
local $stack->{'variables'}->{'DIRECTORY'} = File::Spec->catpath($volume, $directory, '');
}
local $stack->{'variables'}->{'FILE'} = $filename;
local $stack->{'variables'}->{'LINE'} = 0;
local *FILE;
open(FILE, $filename) or die "Couldn't open $filename: $!\n";
while (<FILE>) {
# on cygwin, line endings are screwed up, so normalise them.
s/[\x0D\x0A]+$/\n/os if $^O eq 'cygwin';
$stack->newline;
if (/^\#([a-z]+)\n?$/os) { # argumentless processing instruction
process($stack, $1);
} elsif (/^\#([a-z]+)\s(.*?)\n?$/os) { # processing instruction with arguments
process($stack, $1, $2);
} elsif (/^\#\n?/os) { # comment
# ignore it
} elsif ($stack->enabled) {
# print it, including any newlines
print filtered($stack, $_);
}
}
close(FILE);
}
sub process {
my($stack, $instruction, @arguments) = @_;
my $method = 'preprocessor'->can($instruction);
if (not defined($method)) {
fatal($stack, 'unknown instruction', $instruction);
}
eval { &$method($stack, @arguments) };
if ($@) {
fatal($stack, "error evaluating $instruction:", $@);
}
}
sub filtered {
my($stack, $text) = @_;
foreach my $filter (sort keys %{$stack->{'filters'}}) {
next unless $stack->{'filters'}->{$filter};
my $method = 'filter'->can($filter);
if (not defined($method)) {
fatal($stack, 'unknown filter', $filter);
}
$text = eval { &$method($stack, $text) };
if ($@) {
fatal($stack, "error using $filter:", $@);
}
}
return $text;
}
sub fatal {
my $stack = shift;
my $filename = $stack->{'variables'}->{'FILE'};
local $" = ' ';
print STDERR "$0:$filename:$.: @_\n";
exit(1);
}
########################################################################
package stack;
sub new {
return bless {
'variables' => {
# %ENV,
'LINE' => 0, # the line number in the source file
'DIRECTORY' => '', # current directory
'FILE' => '', # source filename
'1' => 1, # for convenience
},
'filters' => {
# filters
},
'values' => [], # the value of the last condition evaluated at the nth lewel
'lastPrinting' => [], # whether we were printing at the n-1th level
'printing' => 1, # whether we are currently printing at the Nth level
};
}
sub newline {
my $self = shift;
$self->{'variables'}->{'LINE'}++;
}
sub define {
my $self = shift;
my($variable, $value) = @_;
die "not a valid variable name: '$variable'\n" if $variable =~ m/\W/;
$self->{'variables'}->{$variable} = $value;
}
sub defined {
my $self = shift;
my($variable) = @_;
die "not a valid variable name: '$variable'\n" if $variable =~ m/\W/;
return defined($self->{'variables'}->{$variable});
}
sub undefine {
my $self = shift;
my($variable) = @_;
die "not a valid variable name: '$variable'\n" if $variable =~ m/\W/;
delete($self->{'variables'}->{$variable});
}
sub get {
my $self = shift;
my($variable) = @_;
die "not a valid variable name: '$variable'\n" if $variable =~ m/\W/;
my $value = $self->{'variables'}->{$variable};
if (defined($value)) {
return $value;
} else {
return '';
}
}
sub push {
my $self = shift;
my($value) = @_;
push(@{$self->{'values'}}, $value);
push(@{$self->{'lastPrinting'}}, $self->{'printing'});
$self->{'printing'} = $value && $self->{'printing'};
}
sub pop {
my $self = shift;
$self->{'printing'} = pop(@{$self->{'lastPrinting'}});
return pop(@{$self->{'values'}});
}
sub enabled {
my $self = shift;
return $self->{'printing'};
}
sub disabled {
my $self = shift;
return not $self->{'printing'};
}
sub filter {
my $self = shift;
my($filter, $value) = @_;
die "not a valid filter name: '$filter'\n" if $filter =~ m/\W/;
$self->{'filters'}->{$filter} = $value;
}
sub expand {
my $self = shift;
my($line) = @_;
$line =~ s/__(\w+)__/$self->get($1)/gose;
return $line;
}
########################################################################
package preprocessor;
sub define {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
my $argument = shift;
for ($argument) {
/^(\w+)\s(.*)$/os && do {
return $stack->define($1, $2);
};
/^(\w+)$/os && do {
return $stack->define($1, 1);
};
die "invalid argument: '$_'\n";
}
}
sub undef {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
$stack->undefine(@_);
}
sub ifdef {
my $stack = shift;
die "argument expected\n" unless @_;
$stack->push($stack->defined(@_));
}
sub ifndef {
my $stack = shift;
die "argument expected\n" unless @_;
$stack->push(not $stack->defined(@_));
}
sub if {
my $stack = shift;
die "argument expected\n" unless @_;
my $argument = shift;
for ($argument) {
/^(\w+)==(.*)$/os && do {
# equality
return $stack->push($stack->get($1) eq $2);
};
/^(\w+)!=(.*)$/os && do {
# inequality
return $stack->push($stack->get($1) ne $2);
};
/^(\w+)$/os && do {
# true value
return $stack->push($stack->get($1));
};
/^!(\w+)$/os && do {
# false value
return $stack->push(not $stack->get($1));
};
die "invalid argument: '$_'\n";
}
}
sub else {
my $stack = shift;
die "argument unexpected\n" if @_;
$stack->push(not $stack->pop);
}
sub elif {
my $stack = shift;
die "argument expected\n" unless @_;
if ($stack->pop) {
$stack->push(0);
} else {
&if($stack, @_);
}
}
sub elifdef {
my $stack = shift;
die "argument expected\n" unless @_;
if ($stack->pop) {
$stack->push(0);
} else {
&ifdef($stack, @_);
}
}
sub elifndef {
my $stack = shift;
die "argument expected\n" unless @_;
if ($stack->pop) {
$stack->push(0);
} else {
&ifndef($stack, @_);
}
}
sub endif {
my $stack = shift;
die "argument unexpected\n" if @_;
$stack->pop;
}
sub error {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
my $line = $stack->expand(@_);
die "$line\n";
}
sub expand {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
my $line = $stack->expand(@_);
print "$line\n";
}
sub literal {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
my $line = shift;
print "$line\n";
}
sub include {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
main::include($stack, File::Spec->catpath(File::Spec::Unix->splitpath(@_)));
}
sub filter {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
foreach (split(/\s/os, shift)) {
$stack->filter($_, 1);
}
}
sub unfilter {
my $stack = shift;
return if $stack->disabled;
die "argument expected\n" unless @_;
foreach (split(/\s/os, shift)) {
$stack->filter($_, 0);
}
}
########################################################################
package filter;
sub spaces {
my($stack, $text) = @_;
$text =~ s/ +/ /gos; # middle spaces
$text =~ s/^ //gos; # start spaces
$text =~ s/ (\n?)$/$1/gos; # end spaces
return $text;
}
sub slashslash {
my($stack, $text) = @_;
$text =~ s|//.*?(\n?)$|$1|gos;
return $text;
}
########################################################################