diff options
Diffstat (limited to 'sql/sys_vars.cc')
| -rw-r--r-- | sql/sys_vars.cc | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/sql/sys_vars.cc b/sql/sys_vars.cc index 5c9df82ddac..9ca97b5dded 100644 --- a/sql/sys_vars.cc +++ b/sql/sys_vars.cc @@ -1436,7 +1436,6 @@ static Sys_var_ulong Sys_read_buff_size( VALID_RANGE(IO_SIZE*2, INT_MAX32), DEFAULT(128*1024), BLOCK_SIZE(IO_SIZE)); -static my_bool read_only; static bool check_read_only(sys_var *self, THD *thd, set_var *var) { /* Prevent self dead-lock */ @@ -1520,6 +1519,16 @@ static bool fix_read_only(sys_var *self, THD *thd, enum_var_type type) read_only= opt_readonly; DBUG_RETURN(result); } + + +/** + The read_only boolean is always equal to the opt_readonly boolean except + during fix_read_only(); when that function is entered, opt_readonly is + the pre-update value and read_only is the post-update value. + fix_read_only() compares them and runs needed operations for the + transition (especially when transitioning from false to true) and + synchronizes both booleans in the end. +*/ static Sys_var_mybool Sys_readonly( "read_only", "Make all non-temporary tables read-only, with the exception for " |