Rename git_topo_order -> git_changelog, per discussion.

src/tools/RELEASE_CHANGES

@@ -6,7 +6,7 @@ For All Releases (major, minor, beta, RC)
 	  (by packager) (beta)
 
 * Release notes
-	o run git log and, if useful, src/tools/git_topo_order
+	o run git log and, if useful, src/tools/git_changelog
 	o update doc/src/sgml/release.sgml
 	o run spellchecker on result
 	o add SGML markup
@@ -31,7 +31,7 @@ For Major Releases
 (in addition to the above)
 
 * Release notes
-	o use git log or src/tools/git_topo_order to find the relevant commits
+	o use git log or src/tools/git_changelog to find the relevant commits
 	o check completion of items that have been marked as completed at
 	  http://wiki.postgresql.org/wiki/Todo
 	o remove completed TODO items
@@ -76,7 +76,7 @@ Starting a New Development Cycle
 Creating Back-Branch Release Notes
 ==================================
 
-* Run src/tools/git_topo_order to generate a list of relevant commits
+* Run src/tools/git_changelog to generate a list of relevant commits
 
 * On the git master branch, edit and create SGML markup for the most recent
   branch in that branch's release-N.N.sgml file

src/tools/git_topo_order → src/tools/git_changelog

 #!/usr/bin/perl
 
+#
+# src/tools/git_changelog
 #
 # Display all commits on active branches, merging together commits from
 # different branches that occur close together in time and with identical
@@ -18,7 +20,7 @@
 # for the portion of the history we imported from CVS, we expect that they
 # will be.
 #
-# Even though we don't use timestamps to order commits, it is used to
+# Even though we don't use timestamps to order commits, they are used to
 # identify which commits happened at about the same time, for the purpose
 # of matching up commits from different branches.
 #
@@ -29,9 +31,13 @@ require Date::Calc;
 require Getopt::Long;
 require IPC::Open2;
 
+# Adjust this list when the set of active branches changes.
 my @BRANCHES = qw(master REL9_0_STABLE REL8_4_STABLE REL8_3_STABLE
     REL8_2_STABLE REL8_1_STABLE REL8_0_STABLE REL7_4_STABLE);
 
+# Might want to make this parameter user-settable.
+my $timestamp_slop = 600;
+
 my $since;
 Getopt::Long::GetOptions('since=s' => \$since) || usage();
 usage() if @ARGV;
@@ -114,7 +120,7 @@ sub push_commit {
 	my $ts = parse_datetime($c->{'date'});
 	my $cc;
 	for my $candidate (@{$all_commits{$ht}}) {
-		if (abs($ts - $candidate->{'timestamp'}) < 600
+		if (abs($ts - $candidate->{'timestamp'}) < $timestamp_slop
 			&& !exists $candidate->{'branch_position'}{$c->{'branch'}})
 		{
 			$cc = $candidate;
@@ -149,7 +155,7 @@ sub parse_datetime {
 
 sub usage {
 	print STDERR <<EOM;
-Usage: git-topo-order [--since=SINCE]
+Usage: git_changelog [--since=SINCE]
 EOM
 	exit 1;
 }