Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.

There was no way to return an error from the client library
if no MYSQL connections was established.
So here i added variables to store that king of errors and
made functions like mysql_error(NULL) to return these.


client/mysql.cc:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  Show the error message on std_error
include/sql_common.h:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  cant_connect_sqlstate constant declared
libmysql/libmysql.c:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  mysql_sqlstate(NULL) returns 'unknown_sqlstate'
libmysqld/lib_sql.cc:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  EMBEDDED_SERVER version of the vprint_msg_to_log() implemented
sql-common/client.c:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  mysql_server_last_errno and mysql_server_last_error introduced
  to store errors not related to particular connections.
  
  mysql_error(NULL) and mysql_errno(NULL) now returns these
  mysql_server_last_error and errno respectively
sql/log.cc:
  Bug #25097 mysql_server_init fails silently if no errmsg.sys is present.
  
  EMBEDDED_LIBRARY implementation of the vprint_msg_to_log() moved
  to lib_sql.cc

1 files changed, 1 insertions, 6 deletions

diff --git a/sql/log.cc b/sql/log.cc
index e66d965c613..d1da900e1b5 100644
--- a/sql/log.cc
+++ b/sql/log.cc
@@ -2454,12 +2454,7 @@ static void print_buffer_to_nt_eventlog(enum loglevel level, char *buff,
     void
 */
 
-#ifdef EMBEDDED_LIBRARY
-void vprint_msg_to_log(enum loglevel level __attribute__((unused)),
-                       const char *format __attribute__((unused)),
-                       va_list argsi __attribute__((unused)))
-{}
-#else /*!EMBEDDED_LIBRARY*/
+#ifndef EMBEDDED_LIBRARY
 static void print_buffer_to_file(enum loglevel level, const char *buffer)
 {
   time_t skr;