This is an implementation of two WL items:

  - WL#3158: IM: Instance configuration extensions;
  - WL#3159: IM: --bootstrap and --start-default-instance modes

The following new statements have been added:
  - CREATE INSTANCE;
  - DROP INSTANCE;

The behaviour of the following statements have been changed:
  - SET;
  - UNSET;
  - FLUSH INSTANCES;
  - SHOW INSTANCES;
  - SHOW INSTANCE OPTIONS;

1 files changed, 9 insertions, 1 deletions

diff --git a/mysys/default.c b/mysys/default.c
index 580bcc19eca..3a80d7b37b9 100644
--- a/mysys/default.c
+++ b/mysys/default.c
@@ -244,7 +244,8 @@ err:
                             handle_option_ctx structure.
     group_name              The name of the group the option belongs to.
     option                  The very option to be processed. It is already
-                            prepared to be used in argv (has -- prefix)
+                            prepared to be used in argv (has -- prefix). If it
+                            is NULL, we are handling a new group (section).
 
   DESCRIPTION
     This handler checks whether a group is one of the listed and adds an option
@@ -263,6 +264,9 @@ static int handle_default_option(void *in_ctx, const char *group_name,
   char *tmp;
   struct handle_option_ctx *ctx= (struct handle_option_ctx *) in_ctx;
 
+  if (!option)
+    return 0;
+
   if (find_type((char *)group_name, ctx->group, 3))
   {
     if (!(tmp= alloc_root(ctx->alloc, (uint) strlen(option) + 1)))
@@ -719,6 +723,10 @@ static int search_default_file_with_ext(Process_option_func opt_handler,
       end[0]=0;
 
       strnmov(curr_gr, ptr, min((uint) (end-ptr)+1, 4096));
+
+      /* signal that a new group is found */
+      opt_handler(handler_ctx, curr_gr, NULL);
+
       continue;
     }
     if (!found_group)