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)

1 files changed, 10 insertions, 11 deletions

diff --git a/sql/sql_acl.h b/sql/sql_acl.h
index daa36f6c32a..f9646649c93 100644
--- a/sql/sql_acl.h
+++ b/sql/sql_acl.h
@@ -182,10 +182,10 @@ enum mysql_db_table_field
 extern const TABLE_FIELD_DEF mysql_db_table_def;
 extern bool mysql_user_table_is_in_short_password_format;
 
-extern LEX_STRING host_not_specified;
-extern LEX_STRING current_user;
-extern LEX_STRING current_role;
-extern LEX_STRING current_user_and_current_role;
+extern LEX_CSTRING host_not_specified;
+extern LEX_CSTRING current_user;
+extern LEX_CSTRING current_role;
+extern LEX_CSTRING current_user_and_current_role;
 
 
 static inline int access_denied_error_code(int passwd_used)
@@ -194,7 +194,6 @@ static inline int access_denied_error_code(int passwd_used)
                           : ER_ACCESS_DENIED_ERROR;
 }
 
-
 /* prototypes */
 
 bool hostname_requires_resolving(const char *hostname);
@@ -204,8 +203,8 @@ void acl_free(bool end=0);
 ulong acl_get(const char *host, const char *ip,
               const char *user, const char *db, my_bool db_is_pattern);
 bool acl_authenticate(THD *thd, uint com_change_user_pkt_len);
-bool acl_getroot(Security_context *sctx, char *user, char *host,
-                 char *ip, char *db);
+bool acl_getroot(Security_context *sctx, const char *user, const char *host,
+                 const char *ip, const char *db);
 bool acl_check_host(const char *host, const char *ip);
 bool check_change_password(THD *thd, LEX_USER *user);
 bool change_password(THD *thd, LEX_USER *user);
@@ -243,7 +242,7 @@ ulong get_column_grant(THD *thd, GRANT_INFO *grant,
                        const char *db_name, const char *table_name,
                        const char *field_name);
 void mysql_show_grants_get_fields(THD *thd, List<Item> *fields,
-                                  const char *name);
+                                  const char *name, size_t length);
 bool mysql_show_grants(THD *thd, LEX_USER *user);
 bool mysql_show_create_user(THD *thd, LEX_USER *user);
 int fill_schema_enabled_roles(THD *thd, TABLE_LIST *tables, COND *cond);
@@ -385,7 +384,7 @@ public:
 class ACL_internal_schema_registry
 {
 public:
-  static void register_schema(const LEX_STRING *name,
+  static void register_schema(const LEX_CSTRING *name,
                               const ACL_internal_schema_access *access);
   static const ACL_internal_schema_access *lookup(const char *name);
 };
@@ -401,8 +400,8 @@ get_cached_table_access(GRANT_INTERNAL_INFO *grant_internal_info,
 
 bool acl_check_proxy_grant_access (THD *thd, const char *host, const char *user,
                                    bool with_grant);
-int acl_setrole(THD *thd, char *rolename, ulonglong access);
-int acl_check_setrole(THD *thd, char *rolename, ulonglong *access);
+int acl_setrole(THD *thd, const char *rolename, ulonglong access);
+int acl_check_setrole(THD *thd, const char *rolename, ulonglong *access);
 int acl_check_set_default_role(THD *thd, const char *host, const char *user);
 int acl_set_default_role(THD *thd, const char *host, const char *user,
                          const char *rolename);