Fix for BUG#26194 "mysqlbinlog --base64-output produces invalid SQL";

when it was printing a Query event, it produced invalid SQL (missing
the BINLOG keyword, so the SQL started with the base64 string, which
is incorrect).
Note: no testcase; I have a .test which shows that the bugfix works,
but it triggers BUG#26361 and so gives Valgrind warnings. I'm sending
this test to the fixer of BUG#26361 for her/him to push when she/he
fixes BUG#26361.


client/mysqlbinlog.cc:
  writing the header (a line started with "#", i.e. a comment) and the
  body (the real operation) of an event to the same IO_CACHE
  (result_cache) confused the logic of Log_event::print_base64()
  (which is that if the cache is not empty then the BINLOG keyword
  should not be printed); it caused the BINLOG keyword to miss hence
  a syntactically wrong output of "mysqlbinlog --base64-output"
  for Query events.
  So we just use the two IO_CACHE already available in "print_event_info".
sql/log_event.cc:
  using the new small inline function.
  Note that the replication code should one day be fixed to trap all
  errors (like disk write errors).
sql/log_event.h:
  small inline function to group two operations: copying an IO_CACHE
  to a FILE, and reinitializing this IO_CACHE for being filled again.
sql/records.cc:
  fix after merge

client/mysqlbinlog.cc

@@ -483,19 +483,17 @@ static int
 write_event_header_and_base64(Log_event *ev, FILE *result_file,
                               PRINT_EVENT_INFO *print_event_info)
 {
+  IO_CACHE *head= &print_event_info->head_cache;
+  IO_CACHE *body= &print_event_info->body_cache;
   DBUG_ENTER("write_event_header_and_base64");
-  /* Write header and base64 output to cache */
-  IO_CACHE result_cache;
-  if (open_cached_file(&result_cache, NULL, NULL, 0, MYF(MY_WME | MY_NABP)))
-    return 1;
 
-  ev->print_header(&result_cache, print_event_info, FALSE);
-  ev->print_base64(&result_cache, print_event_info, FALSE);
+  /* Write header and base64 output to cache */
+  ev->print_header(head, print_event_info, FALSE);
+  ev->print_base64(body, print_event_info, FALSE);
 
   /* Read data from cache and write to result file */
-  my_b_copy_to_file(&result_cache, result_file);
-  close_cached_file(&result_cache);
-  DBUG_RETURN(0);
+  DBUG_RETURN(copy_event_cache_to_file_and_reinit(head, result_file) ||
+              copy_event_cache_to_file_and_reinit(body, result_file));
 }
 
 

sql/log_event.cc

@@ -75,8 +75,7 @@ public:
 
   ~Write_on_release_cache()
   {
-    if (!my_b_copy_to_file(m_cache, m_file))
-      reinit_io_cache(m_cache, WRITE_CACHE, 0L, FALSE, TRUE);
+    copy_event_cache_to_file_and_reinit(m_cache, m_file);
     if (m_flags | FLUSH_F)
       fflush(m_file);
   }
@@ -6160,10 +6159,8 @@ void Rows_log_event::print_helper(FILE *file,
 
   if (get_flags(STMT_END_F))
   {
-    my_b_copy_to_file(head, file);
-    my_b_copy_to_file(body, file);
-    reinit_io_cache(head, WRITE_CACHE, 0, FALSE, TRUE);
-    reinit_io_cache(body, WRITE_CACHE, 0, FALSE, TRUE);
+    copy_event_cache_to_file_and_reinit(head, file);
+    copy_event_cache_to_file_and_reinit(body, file);
   }
 }
 #endif

sql/log_event.h

@@ -2230,4 +2230,12 @@ private:
 #endif
 };
 
+static inline bool copy_event_cache_to_file_and_reinit(IO_CACHE *cache,
+                                                       FILE *file)
+{
+  return         
+    my_b_copy_to_file(cache, file) ||
+    reinit_io_cache(cache, WRITE_CACHE, 0, FALSE, TRUE);
+}
+
 #endif /* _log_event_h */

sql/records.cc

@@ -150,7 +150,8 @@ void init_read_record(READ_RECORD *info,THD *thd, TABLE *table,
   info->file= table->file;
   info->forms= &info->table;		/* Only one table */
   
-  if (table->s->tmp_table == TMP_TABLE && !table->sort.addon_field)
+  if (table->s->tmp_table == NON_TRANSACTIONAL_TMP_TABLE &&
+      !table->sort.addon_field)
     VOID(table->file->extra(HA_EXTRA_MMAP));
   
   if (table->sort.addon_field)