liblog: add __android_log_config_*_close()

Add __android_log_config_read_close() and
__android_log_config_write_close().  Fortify the list macros
to detect for list corruption, looking for entries pointing
to themselves, deleted entries in list.

Test: gTest liblog-unit-tests
Bug: 27405083
Change-Id: I33e8a0cae7e202f1989ddd7c2a96752b44c8e746
diff --git a/liblog/config_write.h b/liblog/config_write.h
index 3b01a9a..8825411 100644
--- a/liblog/config_write.h
+++ b/liblog/config_write.h
@@ -29,21 +29,30 @@
 #define write_transport_for_each(transp, transports)                         \
     for ((transp) = node_to_item((transports)->next,                         \
                                  struct android_log_transport_write, node);  \
-         ((transp) != node_to_item(transports,                               \
-                                 struct android_log_transport_write, node)); \
+         ((transp) != node_to_item((transports),                             \
+                                   struct android_log_transport_write,       \
+                                   node)) &&                                 \
+         ((transp) != node_to_item((transp)->node.next,                      \
+                                   struct android_log_transport_write,       \
+                                   node));                                   \
          (transp) = node_to_item((transp)->node.next,                        \
-                                 struct android_log_transport_write, node))  \
+                                 struct android_log_transport_write, node))
 
 #define write_transport_for_each_safe(transp, n, transports)                 \
     for ((transp) = node_to_item((transports)->next,                         \
                                  struct android_log_transport_write, node),  \
          (n) = (transp)->node.next;                                          \
-         ((transp) != node_to_item(transports,                               \
-                                   struct android_log_transport_write, node)); \
-         (transp) = node_to_item(n, struct android_log_transport_write, node), \
+         ((transp) != node_to_item((transports),                             \
+                                   struct android_log_transport_write,       \
+                                   node)) &&                                 \
+         ((transp) != node_to_item((n), struct android_log_transport_write,  \
+                                   node));                                   \
+         (transp) = node_to_item((n), struct android_log_transport_write,    \
+                                 node),                                      \
          (n) = (transp)->node.next)
 
 LIBLOG_HIDDEN void __android_log_config_write();
+LIBLOG_HIDDEN void __android_log_config_write_close();
 
 __END_DECLS