BUG#23171 (Illegal slave restart group position):

Second patch to fix skipping code. Moving relay and binary log 
position changing code from do_apply_event [old exec_event()] into
do_update_pos() and doing other changes necessary to support that.

Fixing a bug that can cause deadlock if rotating binary log when committing
a changes to a transactional table that is not inside a transaction and
cause a rotate log.

sql/log.cc

@@ -1453,7 +1453,7 @@ static int binlog_prepare(handlerton *hton, THD *thd, bool all)
     do nothing.
     just pretend we can do 2pc, so that MySQL won't
     switch to 1pc.
-    real work will be done in MYSQL_BIN_LOG::log()
+    real work will be done in TC_LOG_BINLOG::log()
   */
   return 0;
 }
@@ -1467,9 +1467,15 @@ static int binlog_commit(handlerton *hton, THD *thd, bool all)
   IO_CACHE *trans_log= &trx_data->trans_log;
   DBUG_ASSERT(mysql_bin_log.is_open());
 
-  if (all && trx_data->empty())
+  /*
+    The condition here has to be identical to the one inside
+    binlog_end_trans(), guarding the write of the transaction cache to
+    the binary log.
+   */
+  if ((all || !(thd->options & (OPTION_BEGIN | OPTION_NOT_AUTOCOMMIT))) &&
+      trx_data->empty())
   {
-    // we're here because trans_log was flushed in MYSQL_BIN_LOG::log()
+    // we're here because trans_log was flushed in TC_LOG_BINLOG::log()
     trx_data->reset();
     DBUG_RETURN(0);
   }
@@ -3117,8 +3123,10 @@ void MYSQL_BIN_LOG::new_file_impl(bool need_lock)
   {
     tc_log_page_waits++;
     pthread_mutex_lock(&LOCK_prep_xids);
-    while (prepared_xids)
+    while (prepared_xids) {
+      DBUG_PRINT("info", ("prepared_xids=%lu", prepared_xids));
       pthread_cond_wait(&COND_prep_xids, &LOCK_prep_xids);
+    }
     pthread_mutex_unlock(&LOCK_prep_xids);
   }
 
@@ -4905,8 +4913,10 @@ void TC_LOG_BINLOG::unlog(ulong cookie, my_xid xid)
 {
   pthread_mutex_lock(&LOCK_prep_xids);
   DBUG_ASSERT(prepared_xids > 0);
-  if (--prepared_xids == 0)
+  if (--prepared_xids == 0) {
+    DBUG_PRINT("info", ("prepared_xids=%lu", prepared_xids));
     pthread_cond_signal(&COND_prep_xids);
+  }
   pthread_mutex_unlock(&LOCK_prep_xids);
   rotate_and_purge(0);     // as ::write() did not rotate
 }

sql/rpl_rli.cc

@@ -1056,30 +1056,19 @@ void st_relay_log_info::cached_charset_invalidate()
 }
 
 
-bool st_relay_log_info::cached_charset_compare(char *charset)
+bool st_relay_log_info::cached_charset_compare(char *charset) const
 {
   DBUG_ENTER("st_relay_log_info::cached_charset_compare");
 
   if (bcmp(cached_charset, charset, sizeof(cached_charset)))
   {
-    memcpy(cached_charset, charset, sizeof(cached_charset));
+    memcpy(const_cast<char*>(cached_charset), charset, sizeof(cached_charset));
     DBUG_RETURN(1);
   }
   DBUG_RETURN(0);
 }
 
 
-void st_relay_log_info::transaction_end(THD* thd)
-{
-  DBUG_ENTER("st_relay_log_info::transaction_end");
-
-  /*
-    Nothing to do here right now.
-   */
-
-  DBUG_VOID_RETURN;
-}
-
 #if !defined(MYSQL_CLIENT) && defined(HAVE_REPLICATION)
 void st_relay_log_info::cleanup_context(THD *thd, bool error)
 {

sql/rpl_rli.h

@@ -291,9 +291,7 @@ typedef struct st_relay_log_info
     When the 6 bytes are equal to 0 is used to mean "cache is invalidated".
   */
   void cached_charset_invalidate();
-  bool cached_charset_compare(char *charset);
-
-  void transaction_end(THD*);
+  bool cached_charset_compare(char *charset) const;
 
   void cleanup_context(THD *, bool);
   void clear_tables_to_lock() {

sql/rpl_utility.cc

@@ -109,7 +109,7 @@ field_length_from_packed(enum_field_types const field_type,
 
 */
 int
-table_def::compatible_with(RELAY_LOG_INFO *rli, TABLE *table)
+table_def::compatible_with(RELAY_LOG_INFO const *rli_arg, TABLE *table)
   const
 {
   /*
@@ -117,6 +117,7 @@ table_def::compatible_with(RELAY_LOG_INFO *rli, TABLE *table)
   */
   uint const cols_to_check= min(table->s->fields, size());
   int error= 0;
+  RELAY_LOG_INFO const *rli= const_cast<RELAY_LOG_INFO*>(rli_arg);
 
   TABLE_SHARE const *const tsh= table->s;
 

sql/rpl_utility.h

@@ -116,7 +116,7 @@ class table_def
       1  if the table definition is not compatible with 'table'
       0  if the table definition is compatible with 'table'
   */
-  int compatible_with(RELAY_LOG_INFO *rli, TABLE *table) const;
+  int compatible_with(RELAY_LOG_INFO const *rli, TABLE *table) const;
 
 private:
   my_size_t m_size;           // Number of elements in the types array

sql/slave.cc

@@ -555,7 +555,7 @@ static bool sql_slave_killed(THD* thd, RELAY_LOG_INFO* rli)
     void
 */
 
-void slave_print_msg(enum loglevel level, RELAY_LOG_INFO* rli,
+void slave_print_msg(enum loglevel level, RELAY_LOG_INFO const *rli,
                      int err_code, const char* msg, ...)
 {
   void (*report_function)(const char *, ...);
@@ -577,9 +577,9 @@ void slave_print_msg(enum loglevel level, RELAY_LOG_INFO* rli,
       It's an error, it must be reported in Last_error and Last_errno in SHOW
       SLAVE STATUS.
     */
-    pbuff= rli->last_slave_error;
+    pbuff= const_cast<RELAY_LOG_INFO*>(rli)->last_slave_error;
     pbuffsize= sizeof(rli->last_slave_error);
-    rli->last_slave_errno = err_code;
+    const_cast<RELAY_LOG_INFO*>(rli)->last_slave_errno = err_code;
     report_function= sql_print_error;
     break;
   case WARNING_LEVEL:
@@ -1376,7 +1376,7 @@ void set_slave_thread_options(THD* thd)
   DBUG_VOID_RETURN;
 }
 
-void set_slave_thread_default_charset(THD* thd, RELAY_LOG_INFO *rli)
+void set_slave_thread_default_charset(THD* thd, RELAY_LOG_INFO const *rli)
 {
   DBUG_ENTER("set_slave_thread_default_charset");
 
@@ -1387,7 +1387,14 @@ void set_slave_thread_default_charset(THD* thd, RELAY_LOG_INFO *rli)
   thd->variables.collation_server=
     global_system_variables.collation_server;
   thd->update_charset();
-  rli->cached_charset_invalidate();
+
+  /*
+    We use a const cast here since the conceptual (and externally
+    visible) behavior of the function is to set the default charset of
+    the thread.  That the cache has to be invalidated is a secondary
+    effect.
+   */
+  const_cast<RELAY_LOG_INFO*>(rli)->cached_charset_invalidate();
   DBUG_VOID_RETURN;
 }
 
@@ -1607,7 +1614,8 @@ static ulong read_event(MYSQL* mysql, MASTER_INFO *mi, bool* suppress_warnings)
 }
 
 
-int check_expected_error(THD* thd, RELAY_LOG_INFO* rli, int expected_error)
+int check_expected_error(THD* thd, RELAY_LOG_INFO const *rli,
+                         int expected_error)
 {
   DBUG_ENTER("check_expected_error");
 

sql/slave.h

@@ -164,9 +164,9 @@ bool show_master_info(THD* thd, MASTER_INFO* mi);
 bool show_binlog_info(THD* thd);
 
 const char *print_slave_db_safe(const char *db);
-int check_expected_error(THD* thd, RELAY_LOG_INFO* rli, int error_code);
+int check_expected_error(THD* thd, RELAY_LOG_INFO const *rli, int error_code);
 void skip_load_data_infile(NET* net);
-void slave_print_msg(enum loglevel level, RELAY_LOG_INFO* rli,
+void slave_print_msg(enum loglevel level, RELAY_LOG_INFO const *rli,
                      int err_code, const char* msg, ...)
   ATTRIBUTE_FORMAT(printf, 4, 5);
 
@@ -184,7 +184,7 @@ int init_relay_log_pos(RELAY_LOG_INFO* rli,const char* log,ulonglong pos,
 int purge_relay_logs(RELAY_LOG_INFO* rli, THD *thd, bool just_reset,
 		     const char** errmsg);
 void set_slave_thread_options(THD* thd);
-void set_slave_thread_default_charset(THD* thd, RELAY_LOG_INFO *rli);
+void set_slave_thread_default_charset(THD *thd, RELAY_LOG_INFO const *rli);
 void rotate_relay_log(MASTER_INFO* mi);
 
 pthread_handler_t handle_slave_io(void *arg);