From 86ec62ead7d73ba771f33aab48e0ca81c915ced5 Mon Sep 17 00:00:00 2001
From: "alecf%netscape.com" <alecf%netscape.com>
Date: Wed, 12 Sep 2001 16:51:11 +0000
Subject: [PATCH] first time added generates graphviz-style .dot files from
 REQUIRES/MODULE entries in makefiles

---
 tools/module-deps/module-graph.pl | 86 +++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100755 tools/module-deps/module-graph.pl

diff --git a/tools/module-deps/module-graph.pl b/tools/module-deps/module-graph.pl
new file mode 100755
index 000000000000..6775db23e8b5
--- /dev/null
+++ b/tools/module-deps/module-graph.pl
@@ -0,0 +1,86 @@
+#! perl -w
+
+# Todo:
+# - eliminate arcs implied by transitive dependancies
+#   (i.e. in a -> b -> c; a->c;, eliminate a->c;
+# - group together strongly-connected components, where strongly connected
+#   means there exists a cycle, and all dependancies off the cycle.
+
+use Cwd;
+$curdir = getcwd();
+if (!@ARGV) {
+  @dirs = (getcwd());
+} else {
+  @dirs = @ARGV;
+  # XXX does them in reverse order..
+  foreach $arg (@ARGV) {
+    push @dirs, "$curdir/$arg";
+  }
+}
+
+MFILE:
+while ($#dirs != -1) {
+  my ($current_dirs, $current_module, $current_requires);
+  # pop the curdir
+  $curdir = pop @dirs;
+
+  chdir "$curdir";
+  $current_dirs = "";
+  open(MAKEOUT, "nmake /nologo /f makefile.win echo-dirs echo-module echo-requires|") || die "Can't make: $!\n";
+
+  $current_dirs = <MAKEOUT>; $current_dirs && chop $current_dirs;
+  $current_module = <MAKEOUT>; $current_module && chop $current_module;
+  $current_requires = <MAKEOUT>; $current_requires && chop $current_requires;
+  close MAKEOUT;
+
+  if ($current_module) {
+    #
+    # now keep a list of all dependancies of the module
+    #
+    my @require_list = split(/\s+/,$current_requires);
+    foreach $req (@require_list) {
+      $deps{$current_module}{$req}++;
+    }
+  }
+  
+
+  next if !$current_dirs;
+
+  # now push all child directories onto the list
+  @local_dirs = split(/\s+/,$current_dirs);
+  for (@local_dirs) {
+    push @dirs,"$curdir\\$_" if $_;
+  }
+
+}
+
+print "digraph G {\n";
+print "    concentrate=true;\n";
+
+# figure out the internal nodes, and place them in a cluster
+
+print "    subgraph cluster0 {\n";
+print "        node [style=fill];\n";
+print "        color=blue;\n";
+
+foreach $module (sort { scalar keys %{$deps{$b}} <=> scalar keys %{$deps{$a}} } keys %deps) {
+  print "        $module;\n";
+}
+print "    };\n";
+
+# try to figure out "strongly connected components" by looking for cycles
+# keep a list of all visited modules in %clustered
+foreach $module (keys %deps) {
+  next if ($clustered{$module});
+  
+}
+
+foreach $module (sort { scalar keys %{$deps{$b}} <=> scalar keys %{$deps{$a}} } keys %deps) {
+  foreach $req ( sort { $deps{$module}{$b} <=> $deps{$module}{$a} }
+                 keys %{ $deps{$module} } ) {
+#    print "    $module -> $req [weight=$deps{$module}{$req}];\n";
+    print "    $module -> $req;\n";
+  }
+}
+
+print "}";