Bug #40877: multi statement execution fails in 5.1.30

      
Implemented the server infrastructure for the fix:

1. Added a function LEX_STRING *thd_query_string(THD) to return
a LEX_STRING structure instead of char *.
This is the function that must be called in innodb instead of 
thd_query()

2. Did some encapsulation in THD : aggregated thd_query and 
thd_query_length into a LEX_STRING and made accessor and mutator 
methods for easy code updating. 

3. Updated the server code to use the new methods where applicable.

1 files changed, 6 insertions, 6 deletions

diff --git a/sql/sql_show.cc b/sql/sql_show.cc
index 75c9ea6c524..2c1f360104b 100644
--- a/sql/sql_show.cc
+++ b/sql/sql_show.cc
@@ -1864,10 +1864,10 @@ void mysqld_list_processes(THD *thd,const char *user, bool verbose)
         thd_info->query=0;
         /* Lock THD mutex that protects its data when looking at it. */
         pthread_mutex_lock(&tmp->LOCK_thd_data);
-        if (tmp->query)
+        if (tmp->query())
         {
-          uint length= min(max_query_length, tmp->query_length);
-          thd_info->query=(char*) thd->strmake(tmp->query,length);
+          uint length= min(max_query_length, tmp->query_length());
+          thd_info->query= (char*) thd->strmake(tmp->query(),length);
         }
         pthread_mutex_unlock(&tmp->LOCK_thd_data);
         thread_infos.append(thd_info);
@@ -1992,11 +1992,11 @@ int fill_schema_processlist(THD* thd, TABLE_LIST* tables, COND* cond)
         pthread_mutex_unlock(&mysys_var->mutex);
 
       /* INFO */
-      if (tmp->query)
+      if (tmp->query())
       {
-        table->field[7]->store(tmp->query,
+        table->field[7]->store(tmp->query(),
                                min(PROCESS_LIST_INFO_WIDTH,
-                                   tmp->query_length), cs);
+                                   tmp->query_length()), cs);
         table->field[7]->set_notnull();
       }