CHANGES: generate from script

The CHANGES file is now generated automatically with 'git2changes.pl',
invoked by the maketgz script which is used to build release archives.

The former human edited CHANGES file was renamed to CHANGES.0 in git.

git2changes.pl

@@ -0,0 +1,77 @@
+#!/usr/bin/perl
+
+# git log --pretty=fuller --no-color --date=short --decorate=full
+
+my @mname = ('Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
+             'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec' );
+
+sub nicedate {
+    my ($date)=$_;
+
+    if($date =~ /(\d\d\d\d)-(\d\d)-(\d\d)/) {
+        return sprintf("%d %s %4d", $3, $mname[$2-1], $1);
+    }
+    return $date;
+}
+
+print 
+'   Changelog for the c-ares project. Generated with git2changes.pl
+';
+
+my $line;
+my $tag;
+while(<STDIN>) {
+    my $l = $_;
+
+    if($l =~/^commit ([[:xdigit:]]*) ?(.*)/) {
+        $co = $1;
+        my $ref = $2;
+        if ($ref =~ /refs\/tags\/c[-]*ares-([0-9._]*)/) {
+            $tag = $1;
+            $tag =~ s/_/./g;
+        } else {
+            $tag = '';
+        }
+    }
+    elsif($l =~ /^Author: *(.*) +</) {
+        $a = $1;
+    }
+    elsif($l =~ /^Commit: *(.*) +</) {
+        $c = $1;
+    }
+    elsif($l =~ /^CommitDate: (.*)/) {
+        $date = nicedate($1);
+    }
+    elsif($l =~ /^(    )(.*)/) {
+        my $extra;
+        if ($tag) {
+            # Version entries have a special format
+            print "\nVersion " . $tag." ($date)\n";
+            $oldc = "";
+            $tag = "";
+        }
+        if($a ne $c) {
+            $extra=sprintf("\n- [%s brought this change]\n\n  ", $a);
+        }
+        else {
+            $extra="\n- ";
+        }
+        if($co ne $oldco) {
+            if($c ne $oldc) {
+                print "\n$c ($date)$extra";
+            }
+            else {
+                print "$extra";
+            }
+            $line =0;
+        }
+
+        $oldco = $co;
+        $oldc = $c;
+        $olddate = $date;
+        if($line++) {
+            print "  ";
+        }
+        print $2."\n";
+    }
+}