dvander@47: #!/usr/bin/env perl
dvander@47: 
dvander@47: # ***** BEGIN LICENSE BLOCK *****
dvander@47: # Version: MPL 1.1/GPL 2.0/LGPL 2.1
dvander@47: #
dvander@47: # The contents of this file are subject to the Mozilla Public License Version
dvander@47: # 1.1 (the "License"); you may not use this file except in compliance with
dvander@47: # the License. You may obtain a copy of the License at
dvander@47: # http://www.mozilla.org/MPL/
dvander@47: #
dvander@47: # Software distributed under the License is distributed on an "AS IS" basis,
dvander@47: # WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
dvander@47: # for the specific language governing rights and limitations under the
dvander@47: # License.
dvander@47: #
dvander@47: # The Original Code is this file as it was released upon March 8, 1999.
dvander@47: #
dvander@47: # The Initial Developer of the Original Code is
dvander@47: # Netscape Communications Corporation.
dvander@47: # Portions created by the Initial Developer are Copyright (C) 1999
dvander@47: # the Initial Developer. All Rights Reserved.
dvander@47: #
dvander@47: # Contributor(s):
dvander@47: #
dvander@47: # Alternatively, the contents of this file may be used under the terms of
dvander@47: # either of the GNU General Public License Version 2 or later (the "GPL"),
dvander@47: # or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
dvander@47: # in which case the provisions of the GPL or the LGPL are applicable instead
dvander@47: # of those above. If you wish to allow use of your version of this file only
dvander@47: # under the terms of either the GPL or the LGPL, and not to allow others to
dvander@47: # use your version of this file under the terms of the MPL, indicate your
dvander@47: # decision by deleting the provisions above and replace them with the notice
dvander@47: # and other provisions required by the GPL or the LGPL. If you do not delete
dvander@47: # the provisions above, a recipient may use your version of this file under
dvander@47: # the terms of any one of the MPL, the GPL or the LGPL.
dvander@47: #
dvander@47: # ***** END LICENSE BLOCK *****
dvander@47: 
dvander@47: # mddepend.pl - Reads in dependencies generated my -MD flag. Prints list
dvander@47: #   of objects that need to be rebuilt. These can then be added to the
dvander@47: #   PHONY target. Using this script copes with the problem of header
dvander@47: #   files that have been removed from the build.
dvander@47: #    
dvander@47: # Usage:
dvander@47: #   mddepend.pl <output_file> <dependency_files...>
dvander@47: #
dvander@47: # Send comments, improvements, bugs to Steve Lamm (slamm@netscape.com).
dvander@47: 
dvander@47: use strict;
dvander@47: 
dvander@47: use constant DEBUG => 0;
dvander@47: 
dvander@47: my $outfile = shift @ARGV;
dvander@47: my $silent = $ENV{MAKEFLAGS} =~ /^\w*s|\s-s/;
dvander@47: 
dvander@47: my $line = '';
dvander@47: my %alldeps;
dvander@47: # Parse dependency files
dvander@47: while (<>) {
dvander@47:   s/\r?\n$//; # Handle both unix and DOS line endings
dvander@47:   $line .= $_;
dvander@47:   if ($line =~ /\\$/) {
dvander@47:     chop $line;
dvander@47:     next;
dvander@47:   }
dvander@47: 
dvander@47:   $line =~ s|\\|/|g;
dvander@47: 
dvander@47:   my ($obj,$rest) = split /\s*:\s+/, $line, 2;
dvander@47:   $line = '';
dvander@47:   next if !$obj || !$rest;
dvander@47: 
dvander@47:   my @deps = split /\s+/, $rest;
dvander@47:   push @{$alldeps{$obj}}, @deps;
dvander@47:   if (DEBUG >= 2) {
dvander@47:     foreach my $dep (@deps) { print STDERR "add $obj $dep\n"; }
dvander@47:   }
dvander@47: }
dvander@47: 
dvander@47: # Test dependencies
dvander@47: my %modtimes; # cache
dvander@47: my @objs;     # force rebuild on these
dvander@47: OBJ_LOOP: foreach my $obj (keys %alldeps) {
dvander@47:   my $mtime = (stat $obj)[9] or next;
dvander@47: 
dvander@47:   my %not_in_cache;
dvander@47:   my $deps = $alldeps{$obj};
dvander@47:   foreach my $dep_file (@{$deps}) {
dvander@47:     my $dep_mtime = $modtimes{$dep_file};
dvander@47:     if (not defined $dep_mtime) {
dvander@47:       print STDERR "Skipping $dep_file for $obj, will stat() later\n" if DEBUG >= 2;
dvander@47:       $not_in_cache{$dep_file} = 1;
dvander@47:       next;
dvander@47:     }
dvander@47: 
dvander@47:     print STDERR "Found $dep_file in cache\n" if DEBUG >= 2;
dvander@47: 
dvander@47:     if ($dep_mtime > $mtime) {
dvander@47:       print STDERR "$dep_file($dep_mtime) newer than $obj($mtime)\n" if DEBUG;
dvander@47:     }
dvander@47:     elsif ($dep_mtime == -1) {
dvander@47:       print STDERR "Couldn't stat $dep_file for $obj\n" if DEBUG;
dvander@47:     }
dvander@47:     else {
dvander@47:       print STDERR "$dep_file($dep_mtime) older than $obj($mtime)\n" if DEBUG >= 2;
dvander@47:       next;
dvander@47:     }
dvander@47: 
dvander@47:     push @objs, $obj; # dependency is missing or newer
dvander@47:     next OBJ_LOOP; # skip checking the rest of the dependencies
dvander@47:   }
dvander@47: 
dvander@47:   foreach my $dep_file (keys %not_in_cache) {
dvander@47:     print STDERR "STAT $dep_file for $obj\n" if DEBUG >= 2;
dvander@47:     my $dep_mtime = $modtimes{$dep_file} = (stat $dep_file)[9] || -1;
dvander@47: 
dvander@47:     if ($dep_mtime > $mtime) {
dvander@47:       print STDERR "$dep_file($dep_mtime) newer than $obj($mtime)\n" if DEBUG;
dvander@47:     }
dvander@47:     elsif ($dep_mtime == -1) {
dvander@47:       print STDERR "Couldn't stat $dep_file for $obj\n" if DEBUG;
dvander@47:     }
dvander@47:     else {
dvander@47:       print STDERR "$dep_file($dep_mtime) older than $obj($mtime)\n" if DEBUG >= 2;
dvander@47:       next;
dvander@47:     }
dvander@47: 
dvander@47:     push @objs, $obj; # dependency is missing or newer
dvander@47:     next OBJ_LOOP; # skip checking the rest of the dependencies
dvander@47:   }
dvander@47: 
dvander@47:   # If we get here it means nothing needs to be done for $obj
dvander@47: }
dvander@47: 
dvander@47: # Output objects to rebuild (if needed).
dvander@47: if ($outfile eq '-') {
dvander@47:     if (@objs) {
dvander@47: 	print "@objs: FORCE\n";
dvander@47:     }
dvander@47: } elsif (@objs) {
dvander@47:   my $old_output;
dvander@47:   my $new_output = "@objs: FORCE\n";
dvander@47: 
dvander@47:   # Read in the current dependencies file.
dvander@47:   open(OLD, "<$outfile")
dvander@47:     and $old_output = <OLD>;
dvander@47:   close(OLD);
dvander@47: 
dvander@47:   # Only write out the dependencies if they are different.
dvander@47:   if ($new_output ne $old_output) {
dvander@47:     open(OUT, ">$outfile") and print OUT "$new_output";
dvander@47:     print "Updating dependencies file, $outfile\n" unless $silent;
dvander@47:     if (DEBUG) {
dvander@47:       print "new: $new_output\n";
dvander@47:       print "was: $old_output\n" if $old_output ne '';
dvander@47:     }
dvander@47:   }
dvander@47: } elsif (-s $outfile) {
dvander@47:   # Remove the old dependencies because all objects are up to date.
dvander@47:   print "Removing old dependencies file, $outfile\n" unless $silent;
dvander@47: 
dvander@47:   if (DEBUG) {
dvander@47:     my $old_output;
dvander@47:     open(OLD, "<$outfile")
dvander@47:       and $old_output = <OLD>;
dvander@47:     close(OLD);
dvander@47:     print "was: $old_output\n";
dvander@47:   }
dvander@47: 
dvander@47:   unlink $outfile;
dvander@47: }