Fix BUG#2269: Lost connect if stored procedure called before USE

(And some minor correction of cursor open)


sql/sp_head.cc:
  Detect some errors that doesn't result in a non-zero return code in
  the SP execution loop.
  (Also corrected the cursor post_open() call.)
sql/sp_rcontext.cc:
  Corrected the semantics of cursor post_open().
sql/sp_rcontext.h:
  Corrected the semantics of cursor post_open().

sql/sp_head.cc

@@ -286,6 +286,7 @@ sp_head::execute(THD *thd)
 
   if (ctx)
     ctx->clear_handler();
+  thd->query_error= 0;
   do
   {
     sp_instr *i;
@@ -318,10 +319,11 @@ sp_head::execute(THD *thd)
 	continue;
       }
     }
-  } while (ret == 0 && !thd->killed);
+  } while (ret == 0 && !thd->killed && !thd->query_error);
 
-  DBUG_PRINT("info", ("ret=%d killed=%d", ret, thd->killed));
-  if (thd->killed)
+  DBUG_PRINT("info", ("ret=%d killed=%d query_error=%d",
+		      ret, thd->killed, thd->query_error));
+  if (thd->killed || thd->query_error)
     ret= -1;
   /* If the DB has changed, the pointer has changed too, but the
      original thd->db will then have been freed */
@@ -1032,7 +1034,7 @@ sp_instr_copen::execute(THD *thd, uint *nextp)
       res= -1;
     else
       res= exec_stmt(thd, lex);
-    c->post_open(thd, (res == 0 ? TRUE : FALSE));
+    c->post_open(thd, (lex ? TRUE : FALSE));
   }
 
   *nextp= m_ip+1;

sql/sp_rcontext.cc

@@ -153,12 +153,15 @@ sp_cursor::pre_open(THD *thd)
 }
 
 void
-sp_cursor::post_open(THD *thd, my_bool isopen)
+sp_cursor::post_open(THD *thd, my_bool was_opened)
 {
   thd->net.no_send_eof= m_nseof; // Restore the originals
   thd->protocol= m_oprot;
-  m_isopen= isopen;
-  m_current_row= m_prot->data;
+  if (was_opened)
+  {
+    m_isopen= was_opened;
+    m_current_row= m_prot->data;
+  }
 }
 
 int

sql/sp_rcontext.h

@@ -220,7 +220,7 @@ class sp_cursor : public Sql_alloc
   LEX *
   pre_open(THD *thd);
   void
-  post_open(THD *thd, my_bool isopen);
+  post_open(THD *thd, my_bool was_opened);
 
   int
   close(THD *thd);