From 767bb0306067d8b13bc686a79ad9184437455991 Mon Sep 17 00:00:00 2001
From: Thomas Schoebel-Theuer <schoebel@bell.site>
Date: Wed, 25 Dec 2013 19:18:22 +0100
Subject: [PATCH] marsadm: allow overrides of "marsadm secondary" in
 disconnected clusters

When the communication is down in partitioned clusters, the command
"marsadm seconodary" would normally use the current timestamp of
the command execution for the Lamport update protocol.

Make an exception for the case that a concurrent "marsadm primary"
was given somewhere else on a disconnected / partitioned node: let
the "primary" always win over a "secondary" command.
---
 userspace/marsadm | 22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

diff --git a/userspace/marsadm b/userspace/marsadm
index fb0c0c44..7e2a5383 100755
--- a/userspace/marsadm
+++ b/userspace/marsadm
@@ -92,22 +92,20 @@ sub set_link {
 
 sub finish_links {
   return unless @link_list;
-  my $timestamp = time();
-  undef $/;
-  my $lamport = "";
-  if (open(my $fh, "<", "/proc/sys/mars/lamport_clock")) {
-    $lamport = <$fh>;
-  }
-  if ($lamport =~ m/lamport_now=([0-9.]+)/) {
-    $timestamp = $1;
-    lprint "using lamport timestamp $timestamp\n" if $verbose;
-  }
+  my $timestamp = mars_time();
+  lprint "using lamport timestamp $timestamp\n" if $verbose;
   while (my $link = shift @link_list) {
     my $link_tmp = to_tmp($link);
-    system("touch -h -d \"\@$timestamp\" $link_tmp") == 0 or ldie "cannot set mtime on symlink '$link_tmp'\n";
+    my $target = readlink($link_tmp);
+    my $this_timestamp = $timestamp;
+    # allow overriding of secondaries in partitioned clusters by use of small timestamps
+    if ($target eq "(none)") {
+      my @stat = lstat($link);
+      $this_timestamp = $stat[9] + 1 if @stat;
+    }
+    system("touch -h -d \"\@$this_timestamp\" $link_tmp") == 0 or ldie "cannot set mtime on symlink '$link_tmp'\n";
     rename($link_tmp, $link) or ldie "cannot finalize symlink '$link'\n";
     if ($verbose) {
-      my $target = readlink($link);
       lprint "created symlink '$link' -> '$target'\n";
     }
   }