Changing field::field_name and Item::name to LEX_CSTRING

Benefits of this patch:
- Removed a lot of calls to strlen(), especially for field_string
- Strings generated by parser are now const strings, less chance of
  accidently changing a string
- Removed a lot of calls with LEX_STRING as parameter (changed to pointer)
- More uniform code
- Item::name_length was not kept up to date. Now fixed
- Several bugs found and fixed (Access to null pointers,
  access of freed memory, wrong arguments to printf like functions)
- Removed a lot of casts from (const char*) to (char*)

Changes:
- This caused some ABI changes
  - lex_string_set now uses LEX_CSTRING
  - Some fucntions are now taking const char* instead of char*
- Create_field::change and after changed to LEX_CSTRING
- handler::connect_string, comment and engine_name() changed to LEX_CSTRING
- Checked printf() related calls to find bugs. Found and fixed several
  errors in old code.
- A lot of changes from LEX_STRING to LEX_CSTRING, especially related to
  parsing and events.
- Some changes from LEX_STRING and LEX_STRING & to LEX_CSTRING*
- Some changes for char* to const char*
- Added printf argument checking for my_snprintf()
- Introduced null_clex_str, star_clex_string, temp_lex_str to simplify
  code
- Added item_empty_name and item_used_name to be able to distingush between
  items that was given an empty name and items that was not given a name
  This is used in sql_yacc.yy to know when to give an item a name.
- select table_name."*' is not anymore same as table_name.*
- removed not used function Item::rename()
- Added comparision of item->name_length before some calls to
  my_strcasecmp() to speed up comparison
- Moved Item_sp_variable::make_field() from item.h to item.cc
- Some minimal code changes to avoid copying to const char *
- Fixed wrong error message in wsrep_mysql_parse()
- Fixed wrong code in find_field_in_natural_join() where real_item() was
  set when it shouldn't
- ER_ERROR_ON_RENAME was used with extra arguments.
- Removed some (wrong) ER_OUTOFMEMORY, as alloc_root will already
  give the error.

TODO:
- Check possible unsafe casts in plugin/auth_examples/qa_auth_interface.c
- Change code to not modify LEX_CSTRING for database name
  (as part of lower_case_table_names)

6 files changed, 44 insertions, 38 deletions

diff --git a/storage/spider/ha_spider.cc b/storage/spider/ha_spider.cc
index fef18e0e652..a87abfb8073 100644
--- a/storage/spider/ha_spider.cc
+++ b/storage/spider/ha_spider.cc
@@ -7790,7 +7790,8 @@ int ha_spider::cmp_ref(
     ) {
       if ((ret = (*field)->cmp_binary_offset(ptr_diff)))
       {
-        DBUG_PRINT("info",("spider different at %s", (*field)->field_name));
+        DBUG_PRINT("info",("spider different at %s",
+                           (*field)->field_name.str));
         break;
       }
     }
diff --git a/storage/spider/spd_db_conn.cc b/storage/spider/spd_db_conn.cc
index 5b2071b5f1e..96d323a3492 100644
--- a/storage/spider/spd_db_conn.cc
+++ b/storage/spider/spd_db_conn.cc
@@ -1665,7 +1665,7 @@ int spider_db_append_key_where_internal(
 
   if (sql_kind == SPIDER_SQL_KIND_HANDLER)
   {
-    char *key_name = key_info->name;
+    const char *key_name = key_info->name;
     key_name_length = strlen(key_name);
     if (str->reserve(SPIDER_SQL_READ_LEN +
       /* SPIDER_SQL_NAME_QUOTE_LEN */ 2 + key_name_length))
@@ -2844,7 +2844,7 @@ int spider_db_fetch_row(
 ) {
   int error_num;
   DBUG_ENTER("spider_db_fetch_row");
-  DBUG_PRINT("info", ("spider field_name %s", field->field_name));
+  DBUG_PRINT("info", ("spider field_name %s", field->field_name.str));
   DBUG_PRINT("info", ("spider fieldcharset %s", field->charset()->csname));
   field->move_field_offset(ptr_diff);
   error_num = row->store_to_field(field, share->access_charset);
@@ -2967,7 +2967,8 @@ int spider_db_fetch_table(
         my_bitmap_map *tmp_map =
           dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-        DBUG_PRINT("info", ("spider bitmap is set %s", (*field)->field_name));
+        DBUG_PRINT("info", ("spider bitmap is set %s",
+                            (*field)->field_name.str));
         if ((error_num =
           spider_db_fetch_row(share, *field, row, ptr_diff)))
           DBUG_RETURN(error_num);
@@ -3138,7 +3139,7 @@ int spider_db_fetch_key(
       my_bitmap_map *tmp_map =
         dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-      DBUG_PRINT("info", ("spider bitmap is set %s", field->field_name));
+      DBUG_PRINT("info", ("spider bitmap is set %s", field->field_name.str));
       if ((error_num =
         spider_db_fetch_row(share, field, row, ptr_diff)))
         DBUG_RETURN(error_num);
@@ -3252,7 +3253,8 @@ int spider_db_fetch_minimum_columns(
         my_bitmap_map *tmp_map =
           dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-        DBUG_PRINT("info", ("spider bitmap is set %s", (*field)->field_name));
+        DBUG_PRINT("info", ("spider bitmap is set %s",
+                            (*field)->field_name.str));
         if ((error_num = spider_db_fetch_row(share, *field, row, ptr_diff)))
           DBUG_RETURN(error_num);
 #ifndef DBUG_OFF
@@ -5114,7 +5116,8 @@ int spider_db_seek_tmp_table(
       my_bitmap_map *tmp_map =
         dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-      DBUG_PRINT("info", ("spider bitmap is set %s", (*field)->field_name));
+      DBUG_PRINT("info", ("spider bitmap is set %s",
+                          (*field)->field_name.str));
       if ((error_num =
         spider_db_fetch_row(spider->share, *field, row, ptr_diff)))
         DBUG_RETURN(error_num);
@@ -5201,7 +5204,7 @@ int spider_db_seek_tmp_key(
       my_bitmap_map *tmp_map =
         dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-      DBUG_PRINT("info", ("spider bitmap is set %s", field->field_name));
+      DBUG_PRINT("info", ("spider bitmap is set %s", field->field_name.str));
       if ((error_num =
         spider_db_fetch_row(spider->share, field, row, ptr_diff)))
         DBUG_RETURN(error_num);
@@ -5291,7 +5294,8 @@ int spider_db_seek_tmp_minimum_columns(
       my_bitmap_map *tmp_map =
         dbug_tmp_use_all_columns(table, table->write_set);
 #endif
-      DBUG_PRINT("info", ("spider bitmap is set %s", (*field)->field_name));
+      DBUG_PRINT("info", ("spider bitmap is set %s",
+                          (*field)->field_name.str));
       if ((error_num =
         spider_db_fetch_row(spider->share, *field, row, ptr_diff)))
         DBUG_RETURN(error_num);
@@ -5303,7 +5307,7 @@ int spider_db_seek_tmp_minimum_columns(
     else if (bitmap_is_set(table->read_set, (*field)->field_index))
     {
       DBUG_PRINT("info", ("spider bitmap is cleared %s",
-        (*field)->field_name));
+        (*field)->field_name.str));
       bitmap_clear_bit(table->read_set, (*field)->field_index);
     }
   }
@@ -8059,10 +8063,7 @@ int spider_db_open_item_ident(
   }
   if (str)
   {
-    if (item_ident->field_name)
-      field_name_length = strlen(item_ident->field_name);
-    else
-      field_name_length = 0;
+    field_name_length = item_ident->field_name.length;
     if (share->access_charset->cset == system_charset_info->cset)
     {
       if (str->reserve(alias_length +
@@ -8072,7 +8073,7 @@ int spider_db_open_item_ident(
       }
       str->q_append(alias, alias_length);
       if ((error_num = spider_dbton[dbton_id].db_util->
-        append_name(str, item_ident->field_name, field_name_length)))
+        append_name(str, item_ident->field_name.str, field_name_length)))
       {
         DBUG_RETURN(error_num);
       }
@@ -8081,7 +8082,7 @@ int spider_db_open_item_ident(
         DBUG_RETURN(HA_ERR_OUT_OF_MEM);
       str->q_append(alias, alias_length);
       if ((error_num = spider_dbton[dbton_id].db_util->
-        append_name_with_charset(str, item_ident->field_name,
+        append_name_with_charset(str, item_ident->field_name.str,
           field_name_length, system_charset_info)))
       {
         DBUG_RETURN(error_num);
@@ -8140,18 +8141,18 @@ int spider_db_open_item_ref(
       (*(item_ref->ref))->type() != Item::CACHE_ITEM &&
       item_ref->ref_type() != Item_ref::VIEW_REF &&
       !item_ref->table_name &&
-      item_ref->name &&
+      item_ref->name.str &&
       item_ref->alias_name_used
     ) {
       if (str)
       {
-        uint length = strlen(item_ref->name);
+        uint length = item_ref->name.length;
         if (str->reserve(length + /* SPIDER_SQL_NAME_QUOTE_LEN */ 2))
         {
           DBUG_RETURN(HA_ERR_OUT_OF_MEM);
         }
         if ((error_num = spider_dbton[dbton_id].db_util->
-          append_name(str, item_ref->name, length)))
+          append_name(str, item_ref->name.str, length)))
         {
           DBUG_RETURN(error_num);
         }
@@ -9621,7 +9622,7 @@ int spider_db_udf_copy_key_row(
   int error_num;
   DBUG_ENTER("spider_db_udf_copy_key_row");
   if ((error_num = spider_db_append_name_with_quote_str(str,
-    (char *) field->field_name, dbton_id)))
+    (char *) field->field_name.str, dbton_id)))
     DBUG_RETURN(error_num);
   if (str->reserve(joint_length + *length + SPIDER_SQL_AND_LEN))
     DBUG_RETURN(HA_ERR_OUT_OF_MEM);
diff --git a/storage/spider/spd_db_handlersocket.cc b/storage/spider/spd_db_handlersocket.cc
index 47f22b04116..8f031acdbde 100644
--- a/storage/spider/spd_db_handlersocket.cc
+++ b/storage/spider/spd_db_handlersocket.cc
@@ -3904,7 +3904,7 @@ int spider_handlersocket_share::create_column_name_str()
     str->init_calc_mem(202);
     str->set_charset(spider_share->access_charset);
     if ((error_num = spider_db_append_name_with_quote_str(str,
-      (char *) (*field)->field_name, dbton_id)))
+      (char *) (*field)->field_name.str, dbton_id)))
       goto error;
   }
   DBUG_RETURN(0);
diff --git a/storage/spider/spd_db_mysql.cc b/storage/spider/spd_db_mysql.cc
index 1c1c440c2ed..f902508e9c4 100644
--- a/storage/spider/spd_db_mysql.cc
+++ b/storage/spider/spd_db_mysql.cc
@@ -2707,7 +2707,7 @@ void spider_db_mysql::set_dup_key_idx(
   uint roop_count, pk_idx = table->s->primary_key;
   int key_name_length;
   int max_length = 0;
-  char *key_name;
+  const char *key_name;
   DBUG_ENTER("spider_db_mysql::set_dup_key_idx");
   DBUG_PRINT("info",("spider this=%p", this));
   DBUG_PRINT("info",("spider error_str=%s", conn->error_str));
@@ -4560,7 +4560,7 @@ int spider_mysql_share::create_column_name_str()
     str->init_calc_mem(89);
     str->set_charset(spider_share->access_charset);
     if ((error_num = spider_db_append_name_with_quote_str(str,
-      (char *) (*field)->field_name, dbton_id)))
+      (char *) (*field)->field_name.str, dbton_id)))
       goto error;
   }
   DBUG_RETURN(0);
@@ -11882,7 +11882,7 @@ int spider_mysql_copy_table::append_table_columns(
       DBUG_RETURN(HA_ERR_OUT_OF_MEM);
     sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
     if ((error_num = spider_db_append_name_with_quote_str(&sql,
-      (char *) (*field)->field_name, spider_dbton_mysql.dbton_id)))
+      (char *) (*field)->field_name.str, spider_dbton_mysql.dbton_id)))
       DBUG_RETURN(error_num);
     if (sql.reserve(SPIDER_SQL_NAME_QUOTE_LEN + SPIDER_SQL_COMMA_LEN))
       DBUG_RETURN(HA_ERR_OUT_OF_MEM);
@@ -12011,7 +12011,7 @@ int spider_mysql_copy_table::append_key_order_str(
           DBUG_RETURN(HA_ERR_OUT_OF_MEM);
         sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql,
-          (char *) field->field_name, spider_dbton_mysql.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_mysql.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12041,7 +12041,7 @@ int spider_mysql_copy_table::append_key_order_str(
           DBUG_RETURN(HA_ERR_OUT_OF_MEM);
         sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql,
-          (char *) field->field_name, spider_dbton_mysql.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_mysql.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12173,7 +12173,7 @@ int spider_mysql_copy_table::copy_key_row(
     DBUG_RETURN(HA_ERR_OUT_OF_MEM);
   sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
   if ((error_num = spider_db_append_name_with_quote_str(&sql,
-    (char *) field->field_name, spider_dbton_mysql.dbton_id)))
+    (char *) field->field_name.str, spider_dbton_mysql.dbton_id)))
     DBUG_RETURN(error_num);
   if (sql.reserve(SPIDER_SQL_NAME_QUOTE_LEN + joint_length + *length +
     SPIDER_SQL_AND_LEN))
diff --git a/storage/spider/spd_db_oracle.cc b/storage/spider/spd_db_oracle.cc
index c3dfe8b8cf2..5e6c89b10d0 100644
--- a/storage/spider/spd_db_oracle.cc
+++ b/storage/spider/spd_db_oracle.cc
@@ -4361,7 +4361,7 @@ int spider_oracle_share::create_column_name_str()
     str->init_calc_mem(196);
     str->set_charset(spider_share->access_charset);
     if ((error_num = spider_db_append_name_with_quote_str(str,
-      (char *) (*field)->field_name, dbton_id)))
+      (char *) (*field)->field_name.str, dbton_id)))
       goto error;
   }
   DBUG_RETURN(0);
@@ -12031,7 +12031,7 @@ int spider_oracle_copy_table::append_table_columns(
       DBUG_RETURN(HA_ERR_OUT_OF_MEM);
     sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
     if ((error_num = spider_db_append_name_with_quote_str(&sql,
-      (char *) (*field)->field_name, spider_dbton_oracle.dbton_id)))
+      (char *) (*field)->field_name.str, spider_dbton_oracle.dbton_id)))
       DBUG_RETURN(error_num);
     if (sql.reserve(SPIDER_SQL_NAME_QUOTE_LEN + SPIDER_SQL_COMMA_LEN))
       DBUG_RETURN(HA_ERR_OUT_OF_MEM);
@@ -12177,7 +12177,7 @@ int spider_oracle_copy_table::append_key_order_str(
         sql_part.q_append(SPIDER_SQL_NAME_QUOTE_STR,
           SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql_part,
-          (char *) field->field_name, spider_dbton_oracle.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_oracle.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12211,7 +12211,7 @@ int spider_oracle_copy_table::append_key_order_str(
         sql_part.q_append(SPIDER_SQL_NAME_QUOTE_STR,
           SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql_part,
-          (char *) field->field_name, spider_dbton_oracle.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_oracle.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12275,7 +12275,7 @@ int spider_oracle_copy_table::append_key_order_str(
         sql.q_append(SPIDER_SQL_NAME_QUOTE_STR,
           SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql,
-          (char *) field->field_name, spider_dbton_oracle.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_oracle.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12308,7 +12308,7 @@ int spider_oracle_copy_table::append_key_order_str(
         sql.q_append(SPIDER_SQL_NAME_QUOTE_STR,
           SPIDER_SQL_NAME_QUOTE_LEN);
         if ((error_num = spider_db_append_name_with_quote_str(&sql,
-          (char *) field->field_name, spider_dbton_oracle.dbton_id)))
+          (char *) field->field_name.str, spider_dbton_oracle.dbton_id)))
           DBUG_RETURN(error_num);
         if (key_part->key_part_flag & HA_REVERSE_SORT)
         {
@@ -12516,7 +12516,7 @@ int spider_oracle_copy_table::copy_key_row(
     DBUG_RETURN(HA_ERR_OUT_OF_MEM);
   sql.q_append(SPIDER_SQL_NAME_QUOTE_STR, SPIDER_SQL_NAME_QUOTE_LEN);
   if ((error_num = spider_db_append_name_with_quote_str(&sql,
-    (char *) field->field_name, spider_dbton_oracle.dbton_id)))
+    (char *) field->field_name.str, spider_dbton_oracle.dbton_id)))
     DBUG_RETURN(error_num);
   if (sql.reserve(SPIDER_SQL_NAME_QUOTE_LEN + joint_length + *length +
     SPIDER_SQL_AND_LEN))
diff --git a/storage/spider/spd_sys_table.cc b/storage/spider/spd_sys_table.cc
index e1e81394ce8..a140fba7915 100644
--- a/storage/spider/spd_sys_table.cc
+++ b/storage/spider/spd_sys_table.cc
@@ -2386,10 +2386,11 @@ TABLE *spider_mk_sys_tmp_table(
   Item_field *i_field;
   List<Item> i_list;
   TABLE *tmp_table;
+  LEX_CSTRING name= { field_name, strlen(field_name) };
   DBUG_ENTER("spider_mk_sys_tmp_table");
 
   if (!(field = new Field_blob(
-    4294967295U, FALSE, field_name, cs, TRUE)))
+    4294967295U, FALSE, &name, cs, TRUE)))
     goto error_alloc_field;
   field->init(table);
 
@@ -2444,10 +2445,13 @@ TABLE *spider_mk_sys_tmp_table_for_result(
   Item_field *i_field1, *i_field2, *i_field3;
   List<Item> i_list;
   TABLE *tmp_table;
+  LEX_CSTRING name1= { field_name1, strlen(field_name1) };
+  LEX_CSTRING name2= { field_name2, strlen(field_name2) };
+  LEX_CSTRING name3= { field_name3, strlen(field_name3) };
   DBUG_ENTER("spider_mk_sys_tmp_table_for_result");
 
   if (!(field1 = new Field_blob(
-    4294967295U, FALSE, field_name1, cs, TRUE)))
+    4294967295U, FALSE, &name1, cs, TRUE)))
     goto error_alloc_field1;
   field1->init(table);
 
@@ -2463,7 +2467,7 @@ TABLE *spider_mk_sys_tmp_table_for_result(
     goto error_push_item1;
 
   if (!(field2 = new (thd->mem_root) Field_blob(
-    4294967295U, FALSE, field_name2, cs, TRUE)))
+    4294967295U, FALSE, &name2, cs, TRUE)))
     goto error_alloc_field2;
   field2->init(table);
 
@@ -2479,7 +2483,7 @@ TABLE *spider_mk_sys_tmp_table_for_result(
     goto error_push_item2;
 
   if (!(field3 = new (thd->mem_root) Field_blob(
-    4294967295U, FALSE, field_name3, cs, TRUE)))
+    4294967295U, FALSE, &name3, cs, TRUE)))
     goto error_alloc_field3;
   field3->init(table);