LDP: Refactor epoll_ctl wrapper.

- Add AF_UNIX transaction to sock_test_client/server
  echo test to verify mixed epoll ldp implementation.
- Misc cleanup / refactoring of ldp code.
- Fix LDP_DEBUG in test/socket_test.sh

Change-Id: Ib524c824728f109007d8c4d07d74603b6c687902
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/src/vcl/sock_test.h b/src/vcl/sock_test.h
index b4a22ad..0729c31 100644
--- a/src/vcl/sock_test.h
+++ b/src/vcl/sock_test.h
@@ -48,6 +48,11 @@
 #define SOCK_TEST_CFG_BUF_SIZE_MIN    128
 #define SOCK_TEST_CFG_MAX_TEST_SCKTS  5
 
+#define SOCK_TEST_AF_UNIX_FILENAME    "/tmp/ldp_server_af_unix_socket"
+#define SOCK_TEST_MIXED_EPOLL_DATA    "Hello, world! (over an AF_UNIX socket)"
+#define SOCK_TEST_AF_UNIX_ACCEPT_DATA 0xaf0000af
+#define SOCK_TEST_AF_UNIX_FD_MASK     0x00af0000
+
 typedef enum
 {
   SOCK_TEST_TYPE_NONE,
@@ -302,6 +307,13 @@
             stats->stop.tv_sec, stats->stop.tv_nsec);
             
   printf (SOCK_TEST_SEPARATOR_STRING);
+  
+#if SOCK_SERVER_USE_EPOLL && !defined (VCL_TEST)
+  printf ("  af_unix xacts:  %lu (0x%08lx)\n",
+          sock_server_main.af_unix_xacts);
+          
+  printf (SOCK_TEST_SEPARATOR_STRING);
+#endif
 }
 
 static inline int