From 85d5656889bb4a6148974f8817fbd419a45a3797 Mon Sep 17 00:00:00 2001
From:  <brian@gir-2.local>
Date: Wed, 13 Feb 2008 13:12:57 +0530
Subject: [PATCH 1/1] We now sort servers to make sure the client applications
 will always have the same order.

---
 ChangeLog             |  3 +++
 THANKS                |  1 +
 lib/memcached_hosts.c | 32 ++++++++++++++++++++++++++++++++
 tests/function.c      | 23 +++++++++++++++++++++++
 tests/server.c        |  1 -
 5 files changed, 59 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index b7f45663..55dff5f4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -3,6 +3,9 @@
   * Added get_by_key, set_by_key tests for C++ API
   * Fix for limit_maxbytes to be 64bit in stats
   * Added Atom Smasher test (scale baby, scale!)
+  * Servers are now sorted, meaning that servers are now ordered so that
+    clients with the same lists, will have same distribution. (Idea from
+    Ross McFarland).
   
 0.15 Tue Jan 29 14:55:44 PST 2008
   * More work on the C++ API.
diff --git a/THANKS b/THANKS
index a62f3d94..f91fa705 100644
--- a/THANKS
+++ b/THANKS
@@ -5,3 +5,4 @@ Tobias Luetke - Performance Feedback
 Andre Cruz - Help with getting the CRC Hash function to match other connectors
 Brian Pontz - Hsieh hash
 Tim Bunce - Perl Driver work and feedback on API
+Ross McFarland - Idea for sorting servers.
diff --git a/lib/memcached_hosts.c b/lib/memcached_hosts.c
index 760eb391..de006dd6 100644
--- a/lib/memcached_hosts.c
+++ b/lib/memcached_hosts.c
@@ -31,6 +31,25 @@ static void rebalance_wheel(memcached_st *ptr)
   }
 }
 
+static int compare_servers(const void *p1, const void *p2)
+{
+  int return_value;
+  memcached_server_st *a= (memcached_server_st *)p1;
+  memcached_server_st *b= (memcached_server_st *)p2;
+
+  return_value= strcmp(a->hostname, b->hostname);
+
+  if (return_value == 0)
+  {
+    if (a->port > b->port)
+      return_value++;
+    else
+      return_value--;
+  }
+
+  return return_value;
+}
+
 static void host_reset(memcached_st *ptr, memcached_server_st *host, 
                        char *hostname, unsigned int port,
                        memcached_connection type)
@@ -96,6 +115,9 @@ memcached_return memcached_server_push(memcached_st *ptr, memcached_server_st *l
   }
   ptr->hosts[0].count= ptr->number_of_hosts;
 
+  if (ptr->number_of_hosts > 1)
+    qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
+
   rebalance_wheel(ptr);
 
   return MEMCACHED_SUCCESS;
@@ -158,6 +180,9 @@ static memcached_return server_add(memcached_st *ptr, char *hostname,
   ptr->number_of_hosts++;
   ptr->hosts[0].count++;
 
+  if (ptr->number_of_hosts > 1)
+    qsort(ptr->hosts, ptr->number_of_hosts, sizeof(memcached_server_st), compare_servers);
+
   rebalance_wheel(ptr);
 
   LIBMEMCACHED_MEMCACHED_SERVER_ADD_END();
@@ -197,6 +222,13 @@ memcached_server_st *memcached_server_list_append(memcached_server_st *ptr,
   /* Backwards compatibility hack */
   new_host_list[0].count++;
 
+  count= new_host_list[0].count;
+
+  if (new_host_list[0].count > 1)
+    qsort(new_host_list, count, sizeof(memcached_server_st), compare_servers);
+
+  new_host_list[0].count= count;
+
 
   *error= MEMCACHED_SUCCESS;
   return new_host_list;
diff --git a/tests/function.c b/tests/function.c
index 2b01a268..0ead1435 100644
--- a/tests/function.c
+++ b/tests/function.c
@@ -61,6 +61,28 @@ uint8_t server_list_null_test(memcached_st *ptr)
   return 0;
 }
 
+uint8_t server_sort_test(memcached_st *ptr)
+{
+  memcached_server_st *server_list;
+  memcached_return rc;
+
+  server_list= memcached_server_list_append(NULL, "arg", 0, &rc);
+  assert(server_list);
+
+  server_list= memcached_server_list_append(server_list, "localhost", 0, &rc);
+  assert(server_list);
+
+  server_list= memcached_server_list_append(server_list, "c", 0, &rc);
+  assert(server_list);
+
+  server_list= memcached_server_list_append(server_list, "abba", 0, &rc);
+  assert(server_list);
+
+  free(server_list);
+
+  return 0;
+}
+
 uint8_t allocation_test(memcached_st *not_used)
 {
   memcached_st *memc;
@@ -2312,6 +2334,7 @@ test_st tests[] ={
   {"init", 0, init_test },
   {"allocation", 0, allocation_test },
   {"server_list_null_test", 0, server_list_null_test},
+  {"server_sort", 0, server_sort_test},
   {"clone_test", 0, clone_test },
   {"error", 0, error_test },
   {"set", 0, set_test },
diff --git a/tests/server.c b/tests/server.c
index c8e1d98f..8f4dc298 100644
--- a/tests/server.c
+++ b/tests/server.c
@@ -25,7 +25,6 @@ void server_startup(server_startup_st *construct)
   }
   else
   {
-    WATCHPOINT;
     {
       char server_string_buffer[8096];
       char *end_ptr;
-- 
2.30.2