Bug#35054579 Issue in Oracle MySQL Client using utf16 charset

Back porting the bug to 5.7 branch.

Change-Id: I06810ab5d85ac6f65b94ff1d12bc116cf40d7fa1

Author: vsmurthys

client/mysql.cc

@@ -290,7 +290,7 @@ static int com_nopager(String *str, char*), com_pager(String *str, char*),
 #endif
 
 static int read_and_execute(bool interactive);
-static void init_connection_options(MYSQL *mysql);
+static bool init_connection_options(MYSQL *mysql);
 static int sql_connect(char *host,char *database,char *user,char *password,
 		       uint silent);
 static const char *server_version_string(MYSQL *mysql);
@@ -5015,7 +5015,12 @@ sql_real_connect(char *host,char *database,char *user,char *password,
   }
 
   mysql_init(&mysql);
-  init_connection_options(&mysql);
+  if (init_connection_options(&mysql))
+  {
+    (void) put_error(&mysql);
+    (void) fflush(stdout);
+    return ignore_errors ? -1 : 1;		// Abort
+  }
 
 #ifdef _WIN32
   uint cnv_errors;
@@ -5108,7 +5113,7 @@ sql_real_connect(char *host,char *database,char *user,char *password,
 
 
 /* Initialize options for the given connection handle. */
-static void
+static bool
 init_connection_options(MYSQL *mysql)
 {
   my_bool handle_expired= (opt_connect_expired_password || !status.batch) ?
@@ -5151,7 +5156,7 @@ init_connection_options(MYSQL *mysql)
     mysql_options(mysql, MYSQL_INIT_COMMAND, init_command);
   }
 
-  mysql_set_character_set(mysql, default_charset);
+  if (mysql_set_character_set(mysql, default_charset)) return true;
 
   if (opt_plugin_dir && *opt_plugin_dir)
     mysql_options(mysql, MYSQL_PLUGIN_DIR, opt_plugin_dir);
@@ -5170,6 +5175,7 @@ init_connection_options(MYSQL *mysql)
   mysql_options4(mysql, MYSQL_OPT_CONNECT_ATTR_ADD, "program_name", "mysql");
 
   mysql_options(mysql, MYSQL_OPT_CAN_HANDLE_EXPIRED_PASSWORDS, &handle_expired);
+  return false;
 }
 
 

include/errmsg.h

@@ -115,7 +115,8 @@ extern const char *client_errors[];	/* Error messages */
 #define CR_DUPLICATE_CONNECTION_ATTR            2060
 #define CR_AUTH_PLUGIN_ERR                      2061
 #define CR_INSECURE_API_ERR                     2062
-#define CR_ERROR_LAST  /*Copy last error nr:*/  2062
+#define CR_INVALID_CLIENT_CHARSET               2063
+#define CR_ERROR_LAST  /*Copy last error nr:*/  2063
 /* Add error numbers before CR_ERROR_LAST and change it accordingly. */
 
 #endif /* ERRMSG_INCLUDED */

libmysql/errmsg.c

@@ -97,6 +97,9 @@ const char *client_errors[]=
   "There is an attribute with the same name already",
   "Authentication plugin '%s' reported error: %s",
   "Insecure API function call: '%s' Use instead: '%s'",
+  "'%-.32s' character set is having more than 1 byte minimum character "
+  "length, which cannot be used as a client character set. Please use any "
+  "of the single byte minimum ones, e.g. utf8mb4, latin1 etc.",
   ""
 };
 

sql-common/client.c

@@ -5953,6 +5953,11 @@ ulong STDCALL mysql_get_server_version(MYSQL *mysql) {
   return major * 10000 + minor * 100 + version;
 }
 
+#ifndef MYSQL_SERVER
+static my_bool is_supported_parser_charset(const CHARSET_INFO *cs) {
+  return (cs->mbminlen == 1);
+}
+#endif
 /*
    mysql_set_character_set function sends SET NAMES cs_name to
    the server (which changes character_set_client, character_set_result
@@ -5979,6 +5984,17 @@ int STDCALL mysql_set_character_set(MYSQL *mysql, const char *cs_name) {
     cs_name = mysql->options.charset_name;
   }
 
+#ifndef MYSQL_SERVER
+  if (mysql->charset != NULL) {
+    if (!is_supported_parser_charset(mysql->charset)) {
+      set_mysql_extended_error(mysql, CR_INVALID_CLIENT_CHARSET,
+                               unknown_sqlstate,
+                               ER(CR_INVALID_CLIENT_CHARSET), cs_name);
+      return 1;
+    }
+  }
+#endif
+
   if (strlen(cs_name) < MY_CS_NAME_SIZE &&
       (cs = get_charset_by_csname(cs_name, MY_CS_PRIMARY, MYF(0)))) {
     char buff[MY_CS_NAME_SIZE + 10];