bk commit into 5.0 tree (dlenev:1.1918) BUG#12280

[dlenev]

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ChangeSet
  1.1918 05/08/24 23:44:42 dlenev@stripped +1 -0
  Correction of fix for bug #12280 "Triggers: crash if flush tables".
  
  We should not assume that "thd" argument of reload_acl_and_cache() is
  non-zero. Failure to do so will cause server to crash when one sends
  SIGHUP to it.

  sql/sql_parse.cc
    1.474 05/08/24 23:44:33 dlenev@stripped +2 -2
    reload_acl_and_cache():
      When we call this function from SIGHUP handler we pass 0 as "thd" argument
      to it. So we should not assume that thd is non-zero in it.

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	dlenev
# Host:	brandersnatch.localdomain
# Root:	/home/dlenev/src/mysql-5.0.12

--- 1.473/sql/sql_parse.cc	2005-08-24 03:43:16 +04:00
+++ 1.474/sql/sql_parse.cc	2005-08-24 23:44:33 +04:00
@@ -6517,7 +6517,7 @@
 
   SYNOPSIS
     reload_acl_and_cache()
-    thd			Thread handler
+    thd			Thread handler (can be NULL!)
     options             What should be reset/reloaded (tables, privileges,
     slave...)
     tables              Tables to flush (if any)
@@ -6539,7 +6539,7 @@
   select_errors=0;				/* Write if more errors */
   bool tmp_write_to_binlog= 1;
 
-  if (thd->in_sub_stmt)
+  if (thd && thd->in_sub_stmt)
   {
     my_error(ER_STMT_NOT_ALLOWED_IN_SF_OR_TRG, MYF(0), "FLUSH");
     return 1;