Added the ability to get the local port of a memcache_instance_st.

Sometimes when you're hunting bugs on a production webserver (with multiple workers) you want to tcpdump and see what's going on.
This patch adds the memcached_server_srcport method to the library which returns the local sourceport of the connection (if there's a connection).
We use it a lot.

2 files changed, 21 insertions, 0 deletions

diff --git a/libmemcached-1.0/server.h b/libmemcached-1.0/server.h
index 856c0e7e..abd0bfb9 100644
--- a/libmemcached-1.0/server.h
+++ b/libmemcached-1.0/server.h
@@ -104,6 +104,9 @@ LIBMEMCACHED_API
 in_port_t memcached_server_port(const memcached_instance_st * self);
 
 LIBMEMCACHED_API
+in_port_t memcached_server_srcport(const memcached_instance_st * self);
+
+LIBMEMCACHED_API
 void memcached_instance_next_retry(const memcached_instance_st * self, const time_t absolute_time);
 
 LIBMEMCACHED_API
diff --git a/libmemcached/server.cc b/libmemcached/server.cc
index b38120ad..c4747ddc 100644
--- a/libmemcached/server.cc
+++ b/libmemcached/server.cc
@@ -213,6 +213,24 @@ in_port_t memcached_server_port(const memcached_instance_st * self)
   return self->port();
 }
 
+in_port_t memcached_server_srcport(const memcached_instance_st * self)
+{
+  WATCHPOINT_ASSERT(self);
+  if (self == NULL || self->fd == INVALID_SOCKET || (self->type != MEMCACHED_CONNECTION_TCP && self->type != MEMCACHED_CONNECTION_UDP))
+  {
+    return 0;
+  }
+
+  struct sockaddr_in sin;
+  socklen_t addrlen= sizeof(sin);
+  if (getsockname(self->fd, (struct sockaddr*)&sin, &addrlen) != -1)
+  {
+    return ntohs(sin.sin_port);
+  }
+
+  return -1;
+}
+
 uint32_t memcached_server_response_count(const memcached_instance_st * self)
 {
   WATCHPOINT_ASSERT(self);