path: root/utils/h2ph.PL

#!/usr/local/bin/perl

use Config;
use File::Basename qw(&basename &dirname);

# List explicitly here the variables you want Configure to
# generate.  Metaconfig only looks for shell variables, so you
# have to mention them as if they were shell variables, not
# %Config entries.  Thus you write
#  $startperl
# to ensure Configure will look for $Config{startperl}.
# Wanted:  $archlibexp

# This forces PL files to create target in same directory as PL file.
# This is so that make depend always knows where to find PL derivatives.
chdir dirname($0);
$file = basename($0, '.PL');
$file .= '.com' if $^O eq 'VMS';

open OUT,">$file" or die "Can't create $file: $!";

print "Extracting $file (with variable substitutions)\n";

# In this section, perl variables will be expanded during extraction.
# You can use $Config{...} to use Configure variables.

print OUT <<"!GROK!THIS!";
$Config{startperl}
    eval 'exec $Config{perlpath} -S \$0 \${1+"\$@"}'
	if \$running_under_some_shell;
!GROK!THIS!

# In the following, perl variables are not expanded during extraction.

print OUT <<'!NO!SUBS!';

use Config;
use File::Path qw(mkpath);
use Getopt::Std;

getopts('d:rlh');


my $Exit = 0;

my $Dest_dir = $opt_d || $Config{installsitearch};
die "Destination directory $Dest_dir doesn't exist or isn't a directory\n"
    unless -d $Dest_dir;

@isatype = split(' ',<<END);
	char	uchar	u_char
	short	ushort	u_short
	int	uint	u_int
	long	ulong	u_long
	FILE	key_t	caddr_t
END

@isatype{@isatype} = (1) x @isatype;
$inif = 0;

@ARGV = ('-') unless @ARGV;

while (defined ($file = next_file())) {
    if (-l $file and -d $file) {
        link_if_possible($file) if ($opt_l);
        next;
    }

    # Recover from header files with unbalanced cpp directives
    $t = '';
    $tab = 0;

    # $eval_index goes into ``#line'' directives, to help locate syntax errors:
    $eval_index = 1;

    if ($file eq '-') {
	open(IN, "-");
	open(OUT, ">-");
    }
    else {
	($outfile = $file) =~ s/\.h$/.ph/ || next;
	print "$file -> $outfile\n";
	if ($file =~ m|^(.*)/|) {
	    $dir = $1;
	    mkpath "$Dest_dir/$dir";
	}
	open(IN,"$file") || (($Exit = 1),(warn "Can't open $file: $!\n"),next);
	open(OUT,">$Dest_dir/$outfile") || die "Can't create $outfile: $!\n";
    }
    while (<IN>) {
	chop;
	while (/\\$/) {
	    chop;
	    $_ .= <IN>;
	    chop;
	}
	if (s:/\*:\200:g) {
	    s:\*/:\201:g;
	    s/\200[^\201]*\201//g;	# delete single line comments
	    if (s/\200.*//) {		# begin multi-line comment?
		$_ .= '/*';
		$_ .= <IN>;
		redo;
	    }
	}
	if (s/^#\s*//) {
	    if (s/^define\s+(\w+)//) {
		$name = $1;
		$new = '';
		s/\s+$//;
		if (s/^\(([\w,\s]*)\)//) {
		    $args = $1;
    	    	    my $proto = '() ';
		    if ($args ne '') {
    	    	    	$proto = '';
			foreach $arg (split(/,\s*/,$args)) {
			    $arg =~ s/^\s*([^\s].*[^\s])\s*$/$1/;
			    $curargs{$arg} = 1;
			}
			$args =~ s/\b(\w)/\$$1/g;
			$args = "local($args) = \@_;\n$t    ";
		    }
		    s/^\s+//;
		    expr();
		    $new =~ s/(["\\])/\\$1/g;
		    if ($t ne '') {
			$new =~ s/(['\\])/\\$1/g;
			if ($opt_h) {
			    print OUT $t,
                            "eval \"\\n#line $eval_index $outfile\\n\" . 'sub $name $proto\{\n$t    ${args}eval \"$new\";\n$t}' unless defined(\&$name);\n";
                            $eval_index++;
			} else {
			    print OUT $t,
                            "eval 'sub $name $proto\{\n$t    ${args}eval \"$new\";\n$t}' unless defined(\&$name);\n";
			}
		    }
		    else {
                      print OUT "unless (defined(\&$name)) {\nsub $name $proto\{\n    ${args}eval \"$new\";\n}\n}\n";
		    }
		    %curargs = ();
		}
		else {
		    s/^\s+//;
		    expr();
		    $new = 1 if $new eq '';
		    if ($t ne '') {
			$new =~ s/(['\\])/\\$1/g;
			if ($opt_h) {
			    print OUT $t,"eval \"\\n#line $eval_index $outfile\\n\" . 'sub $name () {",$new,";}' unless defined(\&$name);\n";
			    $eval_index++;
			} else {
			    print OUT $t,"eval 'sub $name () {",$new,";}' unless defined(\&$name);\n";
			}
		    }
		    else {
                      print OUT $t,"unless(defined(\&$name)) {\nsub $name () {",$new,";}\n}\n";
		    }
		}
	    }
	    elsif (/^include\s*<(.*)>/) {
		($incl = $1) =~ s/\.h$/.ph/;
		print OUT $t,"require '$incl';\n";
	    }
	    elsif (/^ifdef\s+(\w+)/) {
		print OUT $t,"if (defined &$1) {\n";
		$tab += 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
	    }
	    elsif (/^ifndef\s+(\w+)/) {
		print OUT $t,"if (!defined &$1) {\n";
		$tab += 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
	    }
	    elsif (s/^if\s+//) {
		$new = '';
		$inif = 1;
		expr();
		$inif = 0;
		print OUT $t,"if ($new) {\n";
		$tab += 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
	    }
	    elsif (s/^elif\s+//) {
		$new = '';
		$inif = 1;
		expr();
		$inif = 0;
		$tab -= 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
		print OUT $t,"}\n${t}elsif ($new) {\n";
		$tab += 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
	    }
	    elsif (/^else/) {
		$tab -= 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
		print OUT $t,"}\n${t}else {\n";
		$tab += 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
	    }
	    elsif (/^endif/) {
		$tab -= 4;
		$t = "\t" x ($tab / 8) . ' ' x ($tab % 8);
		print OUT $t,"}\n";
	    }
	}
    }
    print OUT "1;\n";
}

exit $Exit;

sub expr {
    while ($_ ne '') {
	s/^\&\&// && do { $new .= "&&"; next;}; # handle && operator
	s/^\&//;		# hack for things that take the address of
	s/^(\s+)//		&& do {$new .= ' '; next;};
	s/^(0X[0-9A-F]+)[UL]*//i	&& do {$new .= lc($1); next;};
	s/^(-?\d+\.\d+E[-+]\d+)F?//i	&& do {$new .= $1; next;};
	s/^(\d+)\s*[LU]*//i	&& do {$new .= $1; next;};
	s/^("(\\"|[^"])*")//	&& do {$new .= $1; next;};
	s/^'((\\"|[^"])*)'//	&& do {
	    if ($curargs{$1}) {
		$new .= "ord('\$$1')";
	    }
	    else {
		$new .= "ord('$1')";
	    }
	    next;
	};
        # replace "sizeof(foo)" with "{foo}"
        # also, remove * (C dereference operator) to avoid perl syntax
        # problems.  Where the %sizeof array comes from is anyone's
        # guess (c2ph?), but this at least avoids fatal syntax errors.
        # Behavior is undefined if sizeof() delimiters are unbalanced.
        # This code was modified to able to handle constructs like this:
        #   sizeof(*(p)), which appear in the HP-UX 10.01 header files.
        s/^sizeof\s*\(// && do {
            $new .= '$sizeof';
            my $lvl = 1;  # already saw one open paren
            # tack { on the front, and skip it in the loop
            $_ = "{" . "$_";
            my $index = 1;
            # find balanced closing paren
            while ($index <= length($_) && $lvl > 0) {
                $lvl++ if substr($_, $index, 1) eq "(";
                $lvl-- if substr($_, $index, 1) eq ")";
                $index++;
            }
            # tack } on the end, replacing )
            substr($_, $index - 1, 1) = "}";
            # remove pesky * operators within the sizeof argument
            substr($_, 0, $index - 1) =~ s/\*//g;
            next;
        };
	# Eliminate typedefs
	/\(([\w\s]+)[\*\s]*\)\s*[\w\(]/ && do {
	    foreach (split /\s+/, $1) {  # Make sure all the words are types,
		last unless ($isatype{$_} or $_ eq 'struct');
	    }
	    s/\([\w\s]+[\*\s]*\)// && next;      # then eliminate them.
	};
	# struct/union member:
	s/^([_A-Z]\w*((\.|->)[_A-Z]\w*)+)//i && do {
	    $id = $1;
	    $id =~ s/(\.|(->))([^\.-]*)/->\{$3\}/g;
	    $new .= ' ($' . $id . ')';
	};
	s/^([_a-zA-Z]\w*)//	&& do {
	    $id = $1;
	    if ($id eq 'struct') {
		s/^\s+(\w+)//;
		$id .= ' ' . $1;
		$isatype{$id} = 1;
	    }
	    elsif ($id =~ /^((un)?signed)|(long)|(short)$/) {
		while (s/^\s+(\w+)//) { $id .= ' ' . $1; }
		$isatype{$id} = 1;
	    }
	    if ($curargs{$id}) {
		$new .= '$' . $id;
	    }
	    elsif ($id eq 'defined') {
		$new .= 'defined';
	    }
	    elsif (/^\(/) {
		s/^\((\w),/("$1",/ if $id =~ /^_IO[WR]*$/i;	# cheat
		$new .= " &$id";
	    }
	    elsif ($isatype{$id}) {
		if ($new =~ /{\s*$/) {
		    $new .= "'$id'";
		}
		elsif ($new =~ /\(\s*$/ && /^[\s*]*\)/) {
		    $new =~ s/\(\s*$//;
		    s/^[\s*]*\)//;
		}
		else {
		    $new .= q(').$id.q(');
		}
	    }
	    else {
		if ($inif && $new !~ /defined\s*\($/) {
		    $new .= '(defined(&' . $id . ') ? &' . $id . ' : 0)';
		}
		elsif (/^\[/) {
		    $new .= ' $' . $id;
		}
		else {
		    $new .= ' &' . $id;
		}
	    }
	    next;
	};
	s/^(.)// && do { if ($1 ne '#') { $new .= $1; } next;};
    }
}


# Handle recursive subdirectories without getting a grotesquely big stack.
# Could this be implemented using File::Find?
sub next_file
{
    my $file;

    while (@ARGV) {
        $file = shift @ARGV;

        if ($file eq '-' or -f $file or -l $file) {
            return $file;
        } elsif (-d $file) {
            if ($opt_r) {
                expand_glob($file);
            } else {
                print STDERR "Skipping directory `$file'\n";
            }
        } else {
            print STDERR "Skipping `$file':  not a file or directory\n";
        }
    }

    return undef;
}


# Put all the files in $directory into @ARGV for processing.
sub expand_glob
{
    my ($directory)  = @_;

    $directory =~ s:/$::;

    opendir DIR, $directory;
        foreach (readdir DIR) {
            next if ($_ eq '.' or $_ eq '..');

            # expand_glob() is going to be called until $ARGV[0] isn't a
            # directory; so push directories, and unshift everything else.
            if (-d "$directory/$_") { push    @ARGV, "$directory/$_" }
            else                    { unshift @ARGV, "$directory/$_" }
        }
    closedir DIR;
}


# Given $file, a symbolic link to a directory in the C include directory,
# make an equivalent symbolic link in $Dest_dir, if we can figure out how.
# Otherwise, just duplicate the file or directory.
sub link_if_possible
{
    my ($dirlink)  = @_;
    my $target  = eval 'readlink($dirlink)';

    if ($target =~ m:^\.\./: or $target =~ m:^/:) {
        # The target of a parent or absolute link could leave the $Dest_dir
        # hierarchy, so let's put all of the contents of $dirlink (actually,
        # the contents of $target) into @ARGV; as a side effect down the
        # line, $dirlink will get created as an _actual_ directory.
        expand_glob($dirlink);
    } else {
        if (-l "$Dest_dir/$dirlink") {
            unlink "$Dest_dir/$dirlink" or
                print STDERR "Could not remove link $Dest_dir/$dirlink:  $!\n";
        }

        if (eval 'symlink($target, "$Dest_dir/$dirlink")') {
            print "Linking $target -> $Dest_dir/$dirlink\n";

            # Make sure that the link _links_ to something:
            if (! -e "$Dest_dir/$target") {
                mkdir("$Dest_dir/$target", 0755) or
                    print STDERR "Could not create $Dest_dir/$target/\n";
            }
        } else {
            print STDERR "Could not symlink $target -> $Dest_dir/$dirlink:  $!\n";
        }
    }
}


1;

##############################################################################
__END__

=head1 NAME

h2ph - convert .h C header files to .ph Perl header files

=head1 SYNOPSIS

B<h2ph [-d destination directory] [-r] [-l] [headerfiles]>

=head1 DESCRIPTION

I<h2ph>
converts any C header files specified to the corresponding Perl header file
format.
It is most easily run while in /usr/include:

	cd /usr/include; h2ph * sys/*

or

	cd /usr/include; h2ph -r -l .

The output files are placed in the hierarchy rooted at Perl's
architecture dependent library directory.  You can specify a different
hierarchy with a B<-d> switch.

If run with no arguments, filters standard input to standard output.

=head1 OPTIONS

=over 4

=item -d destination_dir

Put the resulting B<.ph> files beneath B<destination_dir>, instead of
beneath the default Perl library location (C<$Config{'installsitsearch'}>).

=item -r

Run recursively; if any of B<headerfiles> are directories, then run I<h2ph>
on all files in those directories (and their subdirectories, etc.).

=item -l

Symbolic links will be replicated in the destination directory.  If B<-l>
is not specified, then links are skipped over.

=item -h

Put ``hints'' in the .ph files which will help in locating problems with
I<h2ph>.  In those cases when you B<require> a B<.ph> file containing syntax
errors, instead of the cryptic

	[ some error condition ] at (eval mmm) line nnn

you will see the slightly more helpful

	[ some error condition ] at filename.ph line nnn

However, the B<.ph> files almost double in size when built using B<-h>.

=back

=head1 ENVIRONMENT

No environment variables are used.

=head1 FILES

 /usr/include/*.h
 /usr/include/sys/*.h

etc.

=head1 AUTHOR

Larry Wall

=head1 SEE ALSO

perl(1)

=head1 DIAGNOSTICS

The usual warnings if it can't read or write the files involved.

=head1 BUGS

Doesn't construct the %sizeof array for you.

It doesn't handle all C constructs, but it does attempt to isolate
definitions inside evals so that you can get at the definitions
that it can translate.

It's only intended as a rough tool.
You may need to dicker with the files produced.

=cut

!NO!SUBS!

close OUT or die "Can't close $file: $!";
chmod 0755, $file or die "Can't reset permissions for $file: $!\n";
exec("$Config{'eunicefix'} $file") if $Config{'eunicefix'} ne ':';