bug #20318 (ctype_ucs2_def test fails with embedded)

there was two problems about charsets in embedded server
1. mysys/charset.c - defined there default_charset_info variable is
modified by both server and client code (particularly when
--default-charset option is handled)
In embedded server we get two codelines modifying one variable.
I created separate default_client_charset_info for client code

2. mysql->charset and mysql->options.charset initialization isn't
properly done for embedded server - necessary calls added

include/sql_common.h

@@ -22,6 +22,7 @@ extern const char	*not_error_sqlstate;
 extern "C" {
 #endif
 
+extern CHARSET_INFO *default_client_charset_info;
 MYSQL_FIELD *unpack_fields(MYSQL_DATA *data,MEM_ROOT *alloc,uint fields,
 			   my_bool default_value, uint server_capabilities);
 void free_rows(MYSQL_DATA *cur);

libmysqld/lib_sql.cc

@@ -41,6 +41,8 @@ static const char *fake_groups[] = { "server", "embedded", 0 };
 int check_user(THD *thd, enum enum_server_command command, 
 	       const char *passwd, uint passwd_len, const char *db,
 	       bool check_count);
+void thd_init_client_charset(THD *thd, uint cs_number);
+
 C_MODE_START
 #include <mysql.h>
 #undef ER
@@ -532,10 +534,13 @@ void *create_embedded_thd(int client_flag, char *db)
   return NULL;
 }
 
+
 #ifdef NO_EMBEDDED_ACCESS_CHECKS
 int check_embedded_connection(MYSQL *mysql)
 {
   THD *thd= (THD*)mysql->thd;
+  thd_init_client_charset(thd, mysql->charset->number);
+  thd->update_charset();
   thd->host= (char*)my_localhost;
   thd->host_or_ip= thd->host;
   thd->user= my_strdup(mysql->user, MYF(0));
@@ -551,6 +556,8 @@ int check_embedded_connection(MYSQL *mysql)
   char scramble_buff[SCRAMBLE_LENGTH];
   int passwd_len;
 
+  thd_init_client_charset(thd, mysql->charset->number);
+  thd->update_charset();
   if (mysql->options.client_ip)
   {
     thd->host= my_strdup(mysql->options.client_ip, MYF(0));

libmysqld/libmysqld.c

@@ -85,49 +85,7 @@ static void end_server(MYSQL *mysql)
 }
 
 
-static int mysql_init_charset(MYSQL *mysql)
-{
-  char charset_name_buff[16], *charset_name;
-
-  if ((charset_name=mysql->options.charset_name))
-  {
-    const char *save=charsets_dir;
-    if (mysql->options.charset_dir)
-      charsets_dir=mysql->options.charset_dir;
-    mysql->charset=get_charset_by_name(mysql->options.charset_name,
-                                       MYF(MY_WME));
-    charsets_dir=save;
-  }
-  else if (mysql->server_language)
-  {
-    charset_name=charset_name_buff;
-    sprintf(charset_name,"%d",mysql->server_language);	/* In case of errors */
-    mysql->charset=get_charset((uint8) mysql->server_language, MYF(MY_WME));
-  }
-  else
-    mysql->charset=default_charset_info;
-
-  if (!mysql->charset)
-  {
-    mysql->net.last_errno=CR_CANT_READ_CHARSET;
-    strmov(mysql->net.sqlstate, "HY0000");
-    if (mysql->options.charset_dir)
-      sprintf(mysql->net.last_error,ER(mysql->net.last_errno),
-              charset_name ? charset_name : "unknown",
-              mysql->options.charset_dir);
-    else
-    {
-      char cs_dir_name[FN_REFLEN];
-      get_charsets_dir(cs_dir_name);
-      sprintf(mysql->net.last_error,ER(mysql->net.last_errno),
-              charset_name ? charset_name : "unknown",
-              cs_dir_name);
-    }
-    return mysql->net.last_errno;
-  }
-  return 0;
-}
-
+int mysql_init_character_set(MYSQL *mysql);
 
 MYSQL * STDCALL
 mysql_real_connect(MYSQL *mysql,const char *host, const char *user,
@@ -203,10 +161,10 @@ mysql_real_connect(MYSQL *mysql,const char *host, const char *user,
 
   init_embedded_mysql(mysql, client_flag, db_name);
 
-  if (check_embedded_connection(mysql))
+  if (mysql_init_character_set(mysql))
     goto error;
 
-  if (mysql_init_charset(mysql))
+  if (check_embedded_connection(mysql))
     goto error;
 
   /* Send client information for access check */

sql-common/client.c

@@ -133,6 +133,8 @@ static void mysql_close_free(MYSQL *mysql);
 static int wait_for_data(my_socket fd, uint timeout);
 #endif
 
+CHARSET_INFO *default_client_charset_info = &my_charset_latin1;
+
 
 /****************************************************************************
   A modified version of connect().  my_connect() allows you to specify
@@ -1424,7 +1426,7 @@ mysql_init(MYSQL *mysql)
     bzero((char*) (mysql),sizeof(*(mysql)));
   mysql->options.connect_timeout= CONNECT_TIMEOUT;
   mysql->last_used_con= mysql->next_slave= mysql->master = mysql;
-  mysql->charset=default_charset_info;
+  mysql->charset=default_client_charset_info;
   strmov(mysql->net.sqlstate, not_error_sqlstate);
   /*
     By default, we are a replication pivot. The caller must reset it
@@ -1537,6 +1539,50 @@ static MYSQL_METHODS client_methods=
 #endif
 };
 
+C_MODE_START
+int mysql_init_character_set(MYSQL *mysql)
+{
+  NET		*net= &mysql->net;
+  /* Set character set */
+  if (!mysql->options.charset_name &&
+      !(mysql->options.charset_name= 
+       my_strdup(MYSQL_DEFAULT_CHARSET_NAME,MYF(MY_WME))))
+    return 1;
+  
+  {
+    const char *save= charsets_dir;
+    if (mysql->options.charset_dir)
+      charsets_dir=mysql->options.charset_dir;
+    mysql->charset=get_charset_by_csname(mysql->options.charset_name,
+                                         MY_CS_PRIMARY, MYF(MY_WME));
+    charsets_dir= save;
+  }
+  
+  if (!mysql->charset)
+  {
+    net->last_errno=CR_CANT_READ_CHARSET;
+    strmov(net->sqlstate, unknown_sqlstate);
+    if (mysql->options.charset_dir)
+      my_snprintf(net->last_error, sizeof(net->last_error)-1,
+                  ER(net->last_errno),
+                  mysql->options.charset_name,
+                  mysql->options.charset_dir);
+    else
+    {
+      char cs_dir_name[FN_REFLEN];
+      get_charsets_dir(cs_dir_name);
+      my_snprintf(net->last_error, sizeof(net->last_error)-1,
+                  ER(net->last_errno),
+                  mysql->options.charset_name,
+                  cs_dir_name);
+    }
+    return 1;
+  }
+  return 0;
+}
+C_MODE_END
+
+
 MYSQL * STDCALL 
 CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
 		       const char *passwd, const char *db,
@@ -1875,42 +1921,8 @@ CLI_MYSQL_REAL_CONNECT(MYSQL *mysql,const char *host, const char *user,
     goto error;
   }
 
-  /* Set character set */
-  if (!mysql->options.charset_name &&
-      !(mysql->options.charset_name= 
-       my_strdup(MYSQL_DEFAULT_CHARSET_NAME,MYF(MY_WME))))
-    goto error;
-  
-  {
-    const char *save= charsets_dir;
-    if (mysql->options.charset_dir)
-      charsets_dir=mysql->options.charset_dir;
-    mysql->charset=get_charset_by_csname(mysql->options.charset_name,
-                                         MY_CS_PRIMARY, MYF(MY_WME));
-    charsets_dir= save;
-  }
-  
-  if (!mysql->charset)
-  {
-    net->last_errno=CR_CANT_READ_CHARSET;
-    strmov(net->sqlstate, unknown_sqlstate);
-    if (mysql->options.charset_dir)
-      my_snprintf(net->last_error, sizeof(net->last_error)-1,
-                  ER(net->last_errno),
-                  mysql->options.charset_name,
-                  mysql->options.charset_dir);
-    else
-    {
-      char cs_dir_name[FN_REFLEN];
-      get_charsets_dir(cs_dir_name);
-      my_snprintf(net->last_error, sizeof(net->last_error)-1,
-                  ER(net->last_errno),
-                  mysql->options.charset_name,
-                  cs_dir_name);
-    }
+  if (mysql_init_character_set(mysql))
     goto error;
-  }
-
 
   /* Save connection information */
   if (!my_multi_malloc(MYF(0),

sql/sql_parse.cc

@@ -667,6 +667,37 @@ static void reset_mqh(THD *thd, LEX_USER *lu, bool get_them= 0)
 #endif /* NO_EMBEDDED_ACCESS_CHECKS */
 }
 
+void thd_init_client_charset(THD *thd, uint cs_number)
+{
+  /*
+   Use server character set and collation if
+   - opt_character_set_client_handshake is not set
+   - client has not specified a character set
+   - client character set is the same as the servers
+   - client character set doesn't exists in server
+  */
+  if (!opt_character_set_client_handshake ||
+      !(thd->variables.character_set_client= get_charset(cs_number, MYF(0))) ||
+      !my_strcasecmp(&my_charset_latin1,
+                     global_system_variables.character_set_client->name,
+                     thd->variables.character_set_client->name))
+  {
+    thd->variables.character_set_client=
+      global_system_variables.character_set_client;
+    thd->variables.collation_connection=
+      global_system_variables.collation_connection;
+    thd->variables.character_set_results=
+      global_system_variables.character_set_results;
+  }
+  else
+  {
+    thd->variables.character_set_results=
+      thd->variables.collation_connection= 
+      thd->variables.character_set_client;
+  }
+}
+
+
 /*
     Perform handshake, authorize client and update thd ACL variables.
   SYNOPSIS
@@ -809,33 +840,7 @@ static int check_connection(THD *thd)
     thd->client_capabilities|= ((ulong) uint2korr(net->read_pos+2)) << 16;
     thd->max_client_packet_length= uint4korr(net->read_pos+4);
     DBUG_PRINT("info", ("client_character_set: %d", (uint) net->read_pos[8]));
-    /*
-      Use server character set and collation if
-      - opt_character_set_client_handshake is not set
-      - client has not specified a character set
-      - client character set is the same as the servers
-      - client character set doesn't exists in server
-    */
-    if (!opt_character_set_client_handshake ||
-        !(thd->variables.character_set_client=
-	  get_charset((uint) net->read_pos[8], MYF(0))) ||
-	!my_strcasecmp(&my_charset_latin1,
-		       global_system_variables.character_set_client->name,
-		       thd->variables.character_set_client->name))
-    {
-      thd->variables.character_set_client=
-	global_system_variables.character_set_client;
-      thd->variables.collation_connection=
-	global_system_variables.collation_connection;
-      thd->variables.character_set_results=
-	global_system_variables.character_set_results;
-    }
-    else
-    {
-      thd->variables.character_set_results=
-      thd->variables.collation_connection= 
-	thd->variables.character_set_client;
-    }
+    thd_init_client_charset(thd, (uint) net->read_pos[8]);
     thd->update_charset();
     end= (char*) net->read_pos+32;
   }