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, 9 insertions, 9 deletions

diff --git a/sql/rpl_mi.h b/sql/rpl_mi.h
index 31c0f280ac1..535abd25f6d 100644
--- a/sql/rpl_mi.h
+++ b/sql/rpl_mi.h
@@ -172,7 +172,7 @@ class Master_info : public Slave_reporting_capability
     USE_GTID_NO= 0, USE_GTID_CURRENT_POS= 1, USE_GTID_SLAVE_POS= 2
   };
 
-  Master_info(LEX_STRING *connection_name, bool is_slave_recovery);
+  Master_info(LEX_CSTRING *connection_name, bool is_slave_recovery);
   ~Master_info();
   bool shall_ignore_server_id(ulong s_id);
   void clear_in_memory_info(bool all);
@@ -197,8 +197,8 @@ class Master_info : public Slave_reporting_capability
   char host[HOSTNAME_LENGTH*SYSTEM_CHARSET_MBMAXLEN+1];
   char user[USERNAME_LENGTH+1];
   char password[MAX_PASSWORD_LENGTH*SYSTEM_CHARSET_MBMAXLEN+1];
-  LEX_STRING connection_name;  		/* User supplied connection name */
-  LEX_STRING cmp_connection_name;	/* Connection name in lower case */
+  LEX_CSTRING connection_name; 		/* User supplied connection name */
+  LEX_CSTRING cmp_connection_name;	/* Connection name in lower case */
   bool ssl; // enables use of SSL connection if true
   char ssl_ca[FN_REFLEN], ssl_capath[FN_REFLEN], ssl_cert[FN_REFLEN];
   char ssl_cipher[FN_REFLEN], ssl_key[FN_REFLEN];
@@ -342,14 +342,14 @@ public:
   HASH master_info_hash;
 
   bool init_all_master_info();
-  bool write_master_name_to_index_file(LEX_STRING *connection_name,
+  bool write_master_name_to_index_file(LEX_CSTRING *connection_name,
                                        bool do_sync);
 
-  bool check_duplicate_master_info(LEX_STRING *connection_name,
+  bool check_duplicate_master_info(LEX_CSTRING *connection_name,
                                    const char *host, uint port);
   bool add_master_info(Master_info *mi, bool write_to_file);
   bool remove_master_info(Master_info *mi);
-  Master_info *get_master_info(const LEX_STRING *connection_name,
+  Master_info *get_master_info(const LEX_CSTRING *connection_name,
                                Sql_condition::enum_warning_level warning);
   bool start_all_slaves(THD *thd);
   bool stop_all_slaves(THD *thd);
@@ -366,13 +366,13 @@ public:
 };
 
 
-Master_info *get_master_info(const LEX_STRING *connection_name,
+Master_info *get_master_info(const LEX_CSTRING *connection_name,
                              Sql_condition::enum_warning_level warning);
-bool check_master_connection_name(LEX_STRING *name);
+bool check_master_connection_name(LEX_CSTRING *name);
 void create_logfile_name_with_suffix(char *res_file_name, size_t length,
                              const char *info_file, 
                              bool append,
-                             LEX_STRING *suffix);
+                             LEX_CSTRING *suffix);
 
 uchar *get_key_master_info(Master_info *mi, size_t *length,
                            my_bool not_used __attribute__((unused)));