Change CHARSET_INFO character set and collaction names to LEX_CSTRING

This change removed 68 explict strlen() calls from the code.

The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name

Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible

Other things:
- There where compiler issues with ensuring that all character set names
  points to the same string: gcc doesn't allow one to use integer constants
  when defining global structures (constant char * pointers works fine).
  To get around this, I declared defines for each character set name
  length.

client/mariadb-conv.cc

@@ -344,15 +344,15 @@ class Conv: public String_copier, public Delimiter
       fflush(stdout);
       fprintf(stderr,
               "Illegal %s byte sequence at position %d\n",
-              m_fromcs->csname,
+              m_fromcs->cs_name.str,
               (uint) (well_formed_error_pos() - from));
     }
     else if (cannot_convert_error_pos())
     {
       fflush(stdout);
       fprintf(stderr,
               "Conversion from %s to %s failed at position %d\n",
-              m_fromcs->csname, m_tocs->csname,
+              m_fromcs->cs_name.str, m_tocs->cs_name.str,
               (uint) (cannot_convert_error_pos() - from));
     }
   }
@@ -453,7 +453,7 @@ int main(int argc, char *argv[])
         charset_info_to->mbminlen > 1)
     {
       fprintf(stderr, "--delimiter cannot be used with %s to %s conversion\n",
-              charset_info_from->csname, charset_info_to->csname);
+              charset_info_from->cs_name.str, charset_info_to->cs_name.str);
       return 1;
     }
     if (conv.set_delimiter_unescape(opt.m_delimiter))

client/mysql.cc

@@ -3246,8 +3246,8 @@ com_charset(String *buffer __attribute__((unused)), char *line)
   if (new_cs)
   {
     charset_info= new_cs;
-    mysql_set_character_set(&mysql, charset_info->csname);
-    default_charset= (char *)charset_info->csname;
+    mysql_set_character_set(&mysql, charset_info->cs_name.str);
+    default_charset= (char *)charset_info->cs_name.str;
     put_info("Charset changed", INFO_INFO);
   }
   else put_info("Charset is not found", INFO_INFO);
@@ -4736,6 +4736,8 @@ static int
 sql_real_connect(char *host,char *database,char *user,char *password,
 		 uint silent)
 {
+  const char *charset_name;
+
   if (connected)
   {
     connected= 0;
@@ -4783,13 +4785,17 @@ sql_real_connect(char *host,char *database,char *user,char *password,
     return -1;					// Retryable
   }
 
-  if (!(charset_info= get_charset_by_name(mysql.charset->name, MYF(MY_UTF8_IS_UTF8MB3))))
+  charset_name= IF_EMBEDDED(mysql.charset->coll_name.str,
+                            mysql.charset->name);
+  charset_info= get_charset_by_name(charset_name, MYF(MY_UTF8_IS_UTF8MB3));
+  if (!charset_info)
   {
-    put_info("Unknown default character set", INFO_ERROR);
+    char buff[128];
+    my_snprintf(buff, sizeof(buff)-1,
+                "Unknown default character set %s", charset_name);
+    put_info(buff, INFO_ERROR);
     return 1;
   }
-
-
   connected=1;
 #ifndef EMBEDDED_LIBRARY
   mysql_options(&mysql, MYSQL_OPT_RECONNECT, &debug_info_flag);
@@ -4928,8 +4934,9 @@ com_status(String *buffer __attribute__((unused)),
   else
   {
     /* Probably pre-4.1 server */
-    tee_fprintf(stdout, "Client characterset:\t%s\n", charset_info->csname);
-    tee_fprintf(stdout, "Server characterset:\t%s\n", mysql.charset->csname);
+    tee_fprintf(stdout, "Client characterset:\t%s\n", charset_info->cs_name.str);
+    tee_fprintf(stdout, "Server characterset:\t%s\n",
+                mysql_character_set_name(&mysql));
   }
 
 #ifndef EMBEDDED_LIBRARY

client/mysqldump.c

@@ -1647,8 +1647,8 @@ static int switch_db_collation(FILE *sql_file,
     fprintf(sql_file,
             "ALTER DATABASE %s CHARACTER SET %s COLLATE %s %s\n",
             (const char *) quoted_db_name,
-            (const char *) db_cl->csname,
-            (const char *) db_cl->name,
+            (const char *) db_cl->cs_name.str,
+            (const char *) db_cl->coll_name.str,
             (const char *) delimiter);
 
     *db_cl_altered= 1;
@@ -1678,8 +1678,8 @@ static int restore_db_collation(FILE *sql_file,
   fprintf(sql_file,
           "ALTER DATABASE %s CHARACTER SET %s COLLATE %s %s\n",
           (const char *) quoted_db_name,
-          (const char *) db_cl->csname,
-          (const char *) db_cl->name,
+          (const char *) db_cl->cs_name.str,
+          (const char *) db_cl->coll_name.str,
           (const char *) delimiter);
 
   return 0;
@@ -4120,7 +4120,7 @@ static void dump_table(const char *table, const char *db, const uchar *hash_key,
 
     dynstr_append_checked(&query_string, " /*!50138 CHARACTER SET ");
     dynstr_append_checked(&query_string, default_charset == mysql_universal_client_charset ?
-                                         my_charset_bin.name : /* backward compatibility */
+                                         my_charset_bin.coll_name.str : /* backward compatibility */
                                          default_charset);
     dynstr_append_checked(&query_string, " */");
 

client/mysqltest.cc

@@ -6010,7 +6010,7 @@ void do_connect(struct st_command *command)
   if (opt_compress || con_compress)
     mysql_options(con_slot->mysql, MYSQL_OPT_COMPRESS, NullS);
   mysql_options(con_slot->mysql, MYSQL_SET_CHARSET_NAME,
-                csname?csname: charset_info->csname);
+                csname ? csname : charset_info->cs_name.str);
   if (opt_charsets_dir)
     mysql_options(con_slot->mysql, MYSQL_SET_CHARSET_DIR,
                   opt_charsets_dir);
@@ -9259,7 +9259,7 @@ int main(int argc, char **argv)
   if (opt_compress)
     mysql_options(con->mysql,MYSQL_OPT_COMPRESS,NullS);
   mysql_options(con->mysql, MYSQL_SET_CHARSET_NAME,
-                charset_info->csname);
+                charset_info->cs_name.str);
   if (opt_charsets_dir)
     mysql_options(con->mysql, MYSQL_SET_CHARSET_DIR,
                   opt_charsets_dir);

include/m_ctype.h

@@ -22,6 +22,7 @@
 #define _m_ctype_h
 
 #include <my_attribute.h>
+#include <m_string.h>
 
 enum loglevel {
    ERROR_LEVEL=       0,
@@ -569,8 +570,8 @@ struct charset_info_st
   uint      primary_number;
   uint      binary_number;
   uint      state;
-  const char *csname;
-  const char *name;
+  LEX_CSTRING cs_name;
+  LEX_CSTRING coll_name;
   const char *comment;
   const char *tailoring;
   const uchar *m_ctype;

include/my_sys.h

@@ -1052,7 +1052,7 @@ extern void free_charsets(void);
 extern char *get_charsets_dir(char *buf);
 static inline my_bool my_charset_same(CHARSET_INFO *cs1, CHARSET_INFO *cs2)
 {
-  return (cs1->csname == cs2->csname);
+  return (cs1->cs_name.str == cs2->cs_name.str);
 }
 extern my_bool init_compiled_charsets(myf flags);
 extern void add_compiled_collation(struct charset_info_st *cs);

libmysqld/libmysql.c

@@ -1114,15 +1114,15 @@ ulong STDCALL mysql_thread_id(MYSQL *mysql)
 
 const char * STDCALL mysql_character_set_name(MYSQL *mysql)
 {
-  return mysql->charset->csname;
+  return mysql->charset->cs_name.str;
 }
 
 void STDCALL mysql_get_character_set_info(MYSQL *mysql, MY_CHARSET_INFO *csinfo)
 {
   csinfo->number   = mysql->charset->number;
   csinfo->state    = mysql->charset->state;
-  csinfo->csname   = mysql->charset->csname;
-  csinfo->name     = mysql->charset->name;
+  csinfo->csname   = mysql->charset->cs_name.str;
+  csinfo->name     = mysql->charset->coll_name.str;
   csinfo->comment  = mysql->charset->comment;
   csinfo->mbminlen = mysql->charset->mbminlen;
   csinfo->mbmaxlen = mysql->charset->mbmaxlen;

mysys/charset-def.c

@@ -468,7 +468,7 @@ my_bool init_compiled_charsets(myf flags __attribute__((unused)))
 #endif /* HAVE_CHARSET_utf32 */
 
   /* Copy compiled charsets */
-  for (cs=compiled_charsets; cs->name; cs++)
+  for (cs=compiled_charsets; cs->coll_name.str; cs++)
     add_compiled_extra_collation((struct charset_info_st *) cs);
 
   return FALSE;