Make dependency generation a bit more robust

Improve the corner cases where we might end up with bogus
dependencies.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

1 files changed, 40 insertions, 31 deletions

diff --git a/tools/mkdep.pl b/tools/mkdep.pl
index eeb044f2..d9373bb5 100755
--- a/tools/mkdep.pl
+++ b/tools/mkdep.pl
@@ -57,8 +57,8 @@ $barrier = "#-- Everything below is generated by mkdep.pl - do not edit --#\n";
 sub scandeps($) {
     my($file) = @_;
     my $line;
-    my @xdeps = ();
-    my @mdeps = ();
+    my %xdeps;
+    my %mdeps;
 
     open(my $fh, '<', $file)
 	or return;		# If not openable, assume generated
@@ -73,14 +73,14 @@ sub scandeps($) {
 		die "$0: cannot determine path for dependency: $file -> $nf\n";
 	    }
 	    $nf = $dep_path{$nf};
-	    push(@mdeps, $nf);
-	    push(@xdeps, $nf) unless ( defined($deps{$nf}) );
+	    $mdeps{$nf}++;
+	    $xdeps{$nf}++ unless ( defined($deps{$nf}) );
 	}
     }
     close($fh);
-    $deps{$file} = [@mdeps];
+    $deps{$file} = [keys(%mdeps)];
 
-    foreach my $xf ( @xdeps ) {
+    foreach my $xf ( keys(%xdeps) ) {
 	scandeps($xf);
     }
 }
@@ -104,6 +104,7 @@ sub alldeps($$) {
 # This almost certainly works only on relative filenames...
 sub convert_file($$) {
     my($file,$sep) = @_;
+
     my @fspec = (basename($file));
     while ( ($file = dirname($file)) ne File::Spec->curdir() &&
 	    $file ne File::Spec->rootdir() ) {
@@ -134,6 +135,8 @@ sub _insert_deps($$) {
     my $sep = '/';
     my $cont = "\\";
     my $include_command = 'include';
+    my $selfrule = 0;
+    my $do_external = 0;
     my $maxline = 78;		# Seems like a reasonable default
     my @exclude = ();		# Don't exclude anything
     my @genhdrs = ();
@@ -167,12 +170,13 @@ sub _insert_deps($$) {
 		$include_command = $val;
 	    } elsif ( $parm eq 'external' ) {
 		# Keep dependencies in an external file
-		if ( $force_inline ) {
-		    next;	# Don't output this line
-		} else {
-		    $external = $val;
-		}
+		$external = $val;
+	    } elsif ( $parm eq 'selfrule' ) {
+		$selfrule = !!$val;
 	    }
+	} elsif ( $line =~ /^(\s*\#?\s*EXTERNAL_DEPENDENCIES\s*=\s*)([01])\s*$/ ) {
+	    $is_external = $externalize ? 1 : $force_inline ? 0 : $2+0;
+	    $line = $1.$is_external."\n";
 	} elsif ( $line eq $barrier ) {
 	    $done = 1;		# Stop reading input at barrier line
 	}
@@ -181,20 +185,16 @@ sub _insert_deps($$) {
     }
     close($in);
 
-    if ( !defined($external) || $externalize ) {
-	# Write the existing Makefile content if we are producing
-	# inline content.  If the Makefile has an
-	# EXTERNAL_DEPENDENCIES definition, update it to match.
-	map { s/\b(EXTERNAL_DEPENDENCIES\s*=\s*)[0-9]+\b/${1}${externalize}/; }
-	    @outfile;
+    $is_external = $is_external && defined($external);
+
+    if ( !$is_external || $externalize ) {
 	print $out @outfile;
     } else {
 	print $out $barrier;	# Start generated file with barrier
     }
 
-
     if ( $externalize ) {
-	if ( defined($external) ) {
+	if ( $is_external ) {
 	    print $out "$include_command $external\n";
 	}
 	return undef;
@@ -206,19 +206,25 @@ sub _insert_deps($$) {
 	$do_exclude{$e} = 1;
     }
 
-    my $dfile, $ofile, $str, $sl, $len;
-    my @deps, $dep;
+    foreach my $dfile ($external, sort(keys(%deps)) ) {
+	my $ofile;
+	my @deps;
+
+	if ( $selfrule && $dfile eq $external ) {
+	    $ofile = convert_file($dfile, $sep).':';
+	    @deps = sort(keys(%deps));
+	} elsif ( $dfile =~ /^(.*)\.[Cc]$/ ) {
+	    $ofile = convert_file($1, $sep).$obj.':';
+	    @deps = ($dfile,alldeps($dfile,1));
+	}
 
-    foreach $dfile ( sort(keys(%deps)) ) {
-	if ( $dfile =~ /^(.*)\.[Cc]$/ ) {
-	    $ofile = $1;
-	    $str = convert_file($ofile, $sep).$obj.':';
-	    $len = length($str);
-	    print $out $str;
-	    foreach $dep ($dfile, alldeps($dfile,1)) {
+	if (defined($ofile)) {
+	    my $len = length($ofile);
+	    print $out $ofile;
+	    foreach my $dep (@deps) {
 		unless ($do_exclude{$dep}) {
-		    $str = convert_file($dep, $sep);
-		    $sl = length($str)+1;
+		    my $str = convert_file($dep, $sep);
+		    my $sl = length($str)+1;
 		    if ( $len+$sl > $maxline-2 ) {
 			print $out ' ', $cont, "\n ", $str;
 			$len = $sl;
@@ -259,6 +265,7 @@ my @mkfiles = ();
 my $mkmode = 0;
 $force_inline = 0;
 $externalize = 0;
+$debug = 0;
 
 while ( defined(my $arg = shift(@ARGV)) ) {
     if ( $arg eq '-m' ) {
@@ -268,6 +275,8 @@ while ( defined(my $arg = shift(@ARGV)) ) {
 	$force_inline = 1;
     } elsif ( $arg eq '-e' ) {
 	$externalize = 1;
+    } elsif ( $arg eq '-d' ) {
+	$debug++;
     } elsif ( $arg eq '-M' ) {
 	$mkmode = 1;		# Futher filenames are output Makefile names
     } elsif ( $arg eq '--' && $mkmode ) {
@@ -294,7 +303,7 @@ foreach my $dir ( @files ) {
 	if ( $file =~ /\.[Cc]$/ ) {
 	    push(@cfiles, $path);
 	} elsif ( $file =~ /\.[Hh]$/ ) {
-	    print STDERR "Filesystem: $file -> $path\n";
+	    print STDERR "Filesystem: $file -> $path\n" if ( $debug );
 	    $dep_path{$file} = $path; # Allow the blank filename
 	    $dep_path{$path} = $path; # Also allow the full pathname
 	}