Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table

Problem was that in mysql-trunk the ER() macro is now dependent on current_thd
and the innodb monitor thread has no binding to that thd object. This cause 
the crash because of bad derefencing.

Solution was to add a new macro which take the thd as an argument (which the innodb
thread uses for the call).

(Updated according to reviewers comments, i.e. added ER_THD_OR_DEFAULT and
moved test to suite parts.)

mysql-test/suite/parts/r/partition_innodb_status_file.result:
  Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table
  
  New test result file
mysql-test/suite/parts/t/partition_innodb_status_file-master.opt:
  Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table
  
  New test opt file
mysql-test/suite/parts/t/partition_innodb_status_file.test:
  Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table
  
  New test.
  Note that the innodb monitor thread only runs every 15 seconds, so this
  test will take at least 15 seconds, so I have moved it to the parts suite.
sql/sql_table.cc:
  Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table
  
  Using thd safe ER macro.
sql/unireg.h:
  Bug#50201: Server crashes in explain_filename on an InnoDB partitioned table
  
  Added ER macros for use with specified thd pointer.

2 files changed, 14 insertions, 6 deletions

diff --git a/sql/sql_table.cc b/sql/sql_table.cc
index b17edbdd234..6006c818725 100644
--- a/sql/sql_table.cc
+++ b/sql/sql_table.cc
@@ -291,7 +291,8 @@ uint explain_filename(THD* thd,
   {
     if (explain_mode == EXPLAIN_ALL_VERBOSE)
     {
-      to_p= strnmov(to_p, ER(ER_DATABASE_NAME), end_p - to_p);
+      to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_DATABASE_NAME),
+                                            end_p - to_p);
       *(to_p++)= ' ';
       to_p= add_identifier(thd, to_p, end_p, db_name, db_name_len);
       to_p= strnmov(to_p, ", ", end_p - to_p);
@@ -304,7 +305,7 @@ uint explain_filename(THD* thd,
   }
   if (explain_mode == EXPLAIN_ALL_VERBOSE)
   {
-    to_p= strnmov(to_p, ER(ER_TABLE_NAME), end_p - to_p);
+    to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_TABLE_NAME), end_p - to_p);
     *(to_p++)= ' ';
     to_p= add_identifier(thd, to_p, end_p, table_name, table_name_len);
   }
@@ -321,18 +322,22 @@ uint explain_filename(THD* thd,
     if (name_type != NORMAL)
     {
       if (name_type == TEMP)
-        to_p= strnmov(to_p, ER(ER_TEMPORARY_NAME), end_p - to_p);
+        to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_TEMPORARY_NAME),
+                      end_p - to_p);
       else
-        to_p= strnmov(to_p, ER(ER_RENAMED_NAME), end_p - to_p);
+        to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_RENAMED_NAME),
+                      end_p - to_p);
       to_p= strnmov(to_p, " ", end_p - to_p);
     }
-    to_p= strnmov(to_p, ER(ER_PARTITION_NAME), end_p - to_p);
+    to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_PARTITION_NAME),
+                  end_p - to_p);
     *(to_p++)= ' ';
     to_p= add_identifier(thd, to_p, end_p, part_name, part_name_len);
     if (subpart_name)
     {
       to_p= strnmov(to_p, ", ", end_p - to_p);
-      to_p= strnmov(to_p, ER(ER_SUBPARTITION_NAME), end_p - to_p);
+      to_p= strnmov(to_p, ER_THD_OR_DEFAULT(thd, ER_SUBPARTITION_NAME),
+                    end_p - to_p);
       *(to_p++)= ' ';
       to_p= add_identifier(thd, to_p, end_p, subpart_name, subpart_name_len);
     }
diff --git a/sql/unireg.h b/sql/unireg.h
index a390b755772..e915b234a6b 100644
--- a/sql/unireg.h
+++ b/sql/unireg.h
@@ -46,6 +46,9 @@
 #define ER(X)         CURRENT_THD_ERRMSGS[(X) - ER_ERROR_FIRST]
 #define ER_DEFAULT(X) DEFAULT_ERRMSGS[(X) - ER_ERROR_FIRST]
 #define ER_SAFE(X) (((X) >= ER_ERROR_FIRST && (X) <= ER_ERROR_LAST) ? ER(X) : "Invalid error code")
+#define ER_THD(thd,X) ((thd)->variables.lc_messages->errmsgs->errmsgs[(X) - \
+                       ER_ERROR_FIRST])
+#define ER_THD_OR_DEFAULT(thd,X) ((thd) ? ER_THD(thd, X) : ER_DEFAULT(X))
 
 
 #define ERRMAPP 1				/* Errormap f|r my_error */