Code cleanup to get fewer reallocs() during execution.

- Changed TABLE->alias to String to get fewer reallocs when alias are used.
- Preallocate some buffers

Changed some String->c_ptr() -> String->ptr() when \0 is not needed.
Fixed wrong usage of String->ptr() when we need a \0 terminated string.
Use my_strtod() instead of my_atof() to avoid having to add \0 to string.
c_ptr() -> c_ptr_safe() to avoid warnings from valgrind.
zr 

sql/event_db_repository.cc:
  Update usage of TABLE->alias
sql/event_scheduler.cc:
  c_ptr() -> c_ptr_safe()
sql/events.cc:
  c_ptr() -> ptr() as \0 was not needed
sql/field.cc:
  Update usage of TABLE->alias
sql/field.h:
  Update usage of TABLE->alias
sql/ha_partition.cc:
  Update usage of TABLE->alias
sql/handler.cc:
  Update usage of TABLE->alias
  Fixed wrong usage of str.ptr()
sql/item.cc:
  Fixed error where code wrongly assumed string was \0 terminated.
sql/item_func.cc:
  c_ptr() -> c_ptr_safe()
  Update usage of TABLE->alias
sql/item_sum.h:
  Use my_strtod() instead of my_atof() to avoid having to add \0 to string
sql/lock.cc:
  Update usage of TABLE->alias
sql/log.cc:
  c_ptr() -> ptr() as \0 was not needed
sql/log_event.cc:
  c_ptr_quick() -> ptr() as \0 was not needed
sql/opt_range.cc:
  ptr() -> c_ptr() as \0 is needed
sql/opt_subselect.cc:
  Update usage of TABLE->alias
sql/opt_table_elimination.cc:
  Update usage of TABLE->alias
sql/set_var.cc:
  ptr() -> c_ptr() as \0 is needed
  c_ptr() -> c_ptr_safe()
sql/sp.cc:
  c_ptr() -> ptr() as \0 was not needed
sql/sp_rcontext.cc:
  
  Update usage of TABLE->alias
sql/sql_base.cc:
  Preallocate buffers
  Update usage of TABLE->alias
sql/sql_class.cc:
  Fix arguments to sprintf() to work even if string is not \0 terminated
sql/sql_insert.cc:
  Update usage of TABLE->alias
  c_ptr() -> ptr() as \0 was not needed
sql/sql_load.cc:
  Preallocate buffers
  Trivial optimizations
sql/sql_parse.cc:
  Trivial optimization
sql/sql_plugin.cc:
  c_ptr() -> ptr() as \0 was not needed
sql/sql_select.cc:
  Update usage of TABLE->alias
sql/sql_show.cc:
  Update usage of TABLE->alias
sql/sql_string.h:
  Added move() function to move allocated memory from one object to another.
sql/sql_table.cc:
  Update usage of TABLE->alias
  c_ptr() -> c_ptr_safe()
sql/sql_test.cc:
  ptr() -> c_ptr_safe()
sql/sql_trigger.cc:
  Update usage of TABLE->alias
  c_ptr() -> c_ptr_safe()
sql/sql_update.cc:
  Update usage of TABLE->alias
sql/sql_view.cc:
  ptr() -> c_ptr_safe()
sql/sql_yacc.yy:
  ptr() -> c_ptr()
sql/table.cc:
  
  Update usage of TABLE->alias
sql/table.h:
  Changed TABLE->alias to String to get fewer reallocs when alias are used.
storage/federatedx/ha_federatedx.cc:
  Use c_ptr_safe() to ensure strings are \0 terminated.
storage/maria/ha_maria.cc:
  Update usage of TABLE->alias
storage/myisam/ha_myisam.cc:
  Update usage of TABLE->alias
storage/xtradb/row/row0sel.c:
  Ensure that null bits in record are properly reset.
  (Old code didn't work as row_search_for_mysql() can be called twice while reading fields from one row.

1 files changed, 10 insertions, 5 deletions

diff --git a/sql/sql_load.cc b/sql/sql_load.cc
index 366c01b1754..75d9179c3bd 100644
--- a/sql/sql_load.cc
+++ b/sql/sql_load.cc
@@ -604,11 +604,15 @@ static bool write_execute_load_query_log_event(THD *thd, sql_exchange* ex,
   size_t               pl= 0;
   List<Item>           fv;
   Item                *item, *val;
-  String               pfield, pfields;
   int                  n;
   const char          *tbl= table_name_arg;
   const char          *tdb= (thd->db != NULL ? thd->db : db_arg);
-  String              string_buf;
+  char 		      name_buffer[SAFE_NAME_LEN*2];
+  char                command_buffer[1024];
+  String              string_buf(name_buffer, sizeof(name_buffer),
+                                 system_charset_info);
+  String              pfields(command_buffer, sizeof(command_buffer),
+                              system_charset_info);
 
   if (!thd->db || strcmp(db_arg, thd->db)) 
   {
@@ -617,7 +621,7 @@ static bool write_execute_load_query_log_event(THD *thd, sql_exchange* ex,
       prefix table name with database name so that it 
       becomes a FQ name.
      */
-    string_buf.set_charset(system_charset_info);
+    string_buf.length(0);
     string_buf.append(db_arg);
     string_buf.append("`");
     string_buf.append(".");
@@ -638,6 +642,7 @@ static bool write_execute_load_query_log_event(THD *thd, sql_exchange* ex,
   /*
     prepare fields-list and SET if needed; print_query won't do that for us.
   */
+  pfields.length(0);
   if (!thd->lex->field_list.is_empty())
   {
     List_iterator<Item>  li(thd->lex->field_list);
@@ -682,8 +687,8 @@ static bool write_execute_load_query_log_event(THD *thd, sql_exchange* ex,
     }
   }
 
-  p= pfields.c_ptr_safe();
-  pl= strlen(p);
+  p=  pfields.c_ptr_safe();
+  pl= pfields.length();
 
   if (!(load_data_query= (char *)thd->alloc(lle.get_query_buffer_length() + 1 + pl)))
     return TRUE;