Backport of revid:ingo.struewing@sun.com-20091223200354-r2uzbdkj2v6yv111

   Bug#47633 - assert in ha_myisammrg::info during OPTIMIZE
 
   The server crashed on an attempt to optimize a MERGE table with
   non-existent child table.
 
   mysql_admin_table() relied on the table to be successfully open
   if a table object had been allocated.
 
   Changed code to check return value of the open function before
   calling a handler:: function on it.

mysql-test/r/merge.result

@@ -1191,6 +1191,9 @@ SHOW CREATE TABLE t4;
 ERROR HY000: Table 't4' was not locked with LOCK TABLES
 INSERT INTO t4 VALUES (4);
 ERROR HY000: Table 't4' was not locked with LOCK TABLES
+# Temporary tables can be created in spite of LOCK TABLES.
+# If the temporary MERGE table uses the locked children only,
+# it can even be used.
 CREATE TEMPORARY TABLE t4 LIKE t3;
 SHOW CREATE TABLE t4;
 ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
@@ -1672,6 +1675,7 @@ c1
 33
 DELETE FROM t4 WHERE c1 = 33;
 DROP TRIGGER t3_ai;
+UNLOCK TABLES;
 #
 # Trigger with table use on child
 DELETE FROM t4 WHERE c1 = 4;
@@ -1854,9 +1858,9 @@ ALTER TABLE t2 UNION=(t3,t1);
 SELECT * FROM t2;
 ERROR HY000: Table 't3' is differently defined or of non-MyISAM type or doesn't exist
 DROP TABLE t1, t2, t3;
-CREATE TABLE t1 (c1 INT) ENGINE= MyISAM;
-CREATE TABLE t2 (c1 INT) ENGINE= MyISAM;
-CREATE TABLE t3 (c1 INT) ENGINE= MRG_MYISAM UNION= (t1, t2);
+CREATE TABLE t1 (c1 INT) ENGINE=MyISAM;
+CREATE TABLE t2 (c1 INT) ENGINE=MyISAM;
+CREATE TABLE t3 (c1 INT) ENGINE=MRG_MYISAM UNION=(t1,t2);
 INSERT INTO t1 VALUES (1);
 INSERT INTO t2 VALUES (2);
 SELECT * FROM t3;
@@ -2635,6 +2639,17 @@ DROP TRIGGER t2_au;
 DROP FUNCTION f1;
 DROP TABLE tm1, t1, t2, t3, t4, t5;
 #
+# Bug#47633 - assert in ha_myisammrg::info during OPTIMIZE
+#
+CREATE TEMPORARY TABLE t1 (c1 INT);
+ALTER TABLE t1 ENGINE=MERGE UNION(t_not_exists,t1);
+OPTIMIZE TABLE t1;
+Table	Op	Msg_type	Msg_text
+test.t1	optimize	Error	Table 'test.t_not_exists' doesn't exist
+test.t1	optimize	Error	Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
+test.t1	optimize	note	The storage engine for the table doesn't support optimize
+DROP TABLE t1;
+#
 # Bug47098 assert in MDL_context::destroy on HANDLER
 #          <damaged merge table> OPEN
 #
@@ -2700,6 +2715,18 @@ ALTER TABLE m1 ADD INDEX (c1);
 UNLOCK TABLES;
 DROP TABLE m1, t1;
 #
+# If children are to be altered, they need an explicit lock.
+#
+CREATE TABLE t1 (c1 INT);
+CREATE TABLE m1 (c1 INT) ENGINE=MRG_MyISAM UNION=(t1);
+LOCK TABLE m1 WRITE;
+ALTER TABLE t1 ADD INDEX (c1);
+ERROR HY000: Table 't1' was locked with a READ lock and can't be updated
+LOCK TABLE m1 WRITE, t1 WRITE;
+ALTER TABLE t1 ADD INDEX (c1);
+UNLOCK TABLES;
+DROP TABLE m1, t1;
+#
 # Test for bug #37371 "CREATE TABLE LIKE merge loses UNION parameter"
 #
 drop tables if exists t1, m1, m2;

mysql-test/t/merge.test

@@ -457,7 +457,7 @@ CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t1);
 SELECT * FROM t2;
 DROP TABLE t1, t2;
 CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t3);
---error 1168
+--error ER_WRONG_MRG_TABLE
 SELECT * FROM t2;
 DROP TABLE t2;
 
@@ -549,11 +549,11 @@ drop table t1;
 #             CREATE TABLE fails
 #
 CREATE TABLE tm1(a INT) ENGINE=MERGE UNION=(t1, t2);
---error 1168
+--error ER_WRONG_MRG_TABLE
 SELECT * FROM tm1;
 CHECK TABLE tm1;
 CREATE TABLE t1(a INT);
---error 1168
+--error ER_WRONG_MRG_TABLE
 SELECT * FROM tm1;
 CHECK TABLE tm1;
 CREATE TABLE t2(a BLOB);
@@ -887,6 +887,9 @@ CREATE TABLE t4 LIKE t3;
 SHOW CREATE TABLE t4;
 --error ER_TABLE_NOT_LOCKED
 INSERT INTO t4 VALUES (4);
+--echo # Temporary tables can be created in spite of LOCK TABLES.
+--echo # If the temporary MERGE table uses the locked children only,
+--echo # it can even be used.
 CREATE TEMPORARY TABLE t4 LIKE t3;
 --error ER_WRONG_MRG_TABLE
 SHOW CREATE TABLE t4;
@@ -913,7 +916,7 @@ DROP TABLE t4;
 --echo # 2. Normal rename.
 SELECT * FROM t3 ORDER BY c1;
 RENAME TABLE t2 TO t5;
---error 1168
+--error ER_WRONG_MRG_TABLE
 SELECT * FROM t3 ORDER BY c1;
 RENAME TABLE t5 TO t2;
 SELECT * FROM t3 ORDER BY c1;
@@ -931,7 +934,7 @@ UNLOCK TABLES;
 --echo #
 --echo # 4. Alter table rename.
 ALTER TABLE t2 RENAME TO t5;
---error 1168
+--error ER_WRONG_MRG_TABLE
 SELECT * FROM t3 ORDER BY c1;
 ALTER TABLE t5 RENAME TO t2;
 SELECT * FROM t3 ORDER BY c1;
@@ -1170,6 +1173,7 @@ SELECT @a;
 SELECT * FROM t4 ORDER BY c1;
 DELETE FROM t4 WHERE c1 = 33;
 DROP TRIGGER t3_ai;
+UNLOCK TABLES;
 --echo #
 --echo # Trigger with table use on child
 DELETE FROM t4 WHERE c1 = 4;
@@ -1273,11 +1277,12 @@ DROP TABLE t1, t2, t3;
 
 #
 # Bug#25038 - Waiting TRUNCATE
+# Truncate failed with error message when table was in use by MERGE.
 #
 # Show that truncate of child table after use of parent table works.
-CREATE TABLE t1 (c1 INT) ENGINE= MyISAM; 
-CREATE TABLE t2 (c1 INT) ENGINE= MyISAM; 
-CREATE TABLE t3 (c1 INT) ENGINE= MRG_MYISAM UNION= (t1, t2); 
+CREATE TABLE t1 (c1 INT) ENGINE=MyISAM; 
+CREATE TABLE t2 (c1 INT) ENGINE=MyISAM; 
+CREATE TABLE t3 (c1 INT) ENGINE=MRG_MYISAM UNION=(t1,t2); 
 INSERT INTO t1 VALUES (1);
 INSERT INTO t2 VALUES (2);
 SELECT * FROM t3;
@@ -1429,7 +1434,6 @@ FLUSH TABLES m1, t1;
 UNLOCK TABLES;
 DROP TABLE t1, m1;
 
-
 #
 # Bug#35068 - Assertion fails when reading from i_s.tables
 #             and there is incorrect merge table
@@ -1816,7 +1820,7 @@ CREATE TABLE m1 (c1 INT) ENGINE=MRG_MYISAM UNION=(t1,mysql_test1.t2)
 INSERT INTO t1 VALUES (1);
 INSERT INTO mysql_test1.t2 VALUES (2);
 SELECT * FROM m1;
-#--copy_file $MYSQLTEST_VARDIR/master-data/test/m1.MRG /tmp/mysql-test-m1.MRG
+#--copy_file $MYSQLTEST_DATADIR/test/m1.MRG /tmp/mysql-test-m1.MRG
 DROP TABLE t1, mysql_test1.t2, m1;
 DROP DATABASE mysql_test1;
 #
@@ -2104,6 +2108,14 @@ DROP TRIGGER t2_au;
 DROP FUNCTION f1;
 DROP TABLE tm1, t1, t2, t3, t4, t5;
 
+--echo #
+--echo # Bug#47633 - assert in ha_myisammrg::info during OPTIMIZE
+--echo #
+CREATE TEMPORARY TABLE t1 (c1 INT);
+ALTER TABLE t1 ENGINE=MERGE UNION(t_not_exists,t1);
+OPTIMIZE TABLE t1;
+DROP TABLE t1;
+
 --echo #
 --echo # Bug47098 assert in MDL_context::destroy on HANDLER
 --echo #          <damaged merge table> OPEN
@@ -2186,6 +2198,18 @@ ALTER TABLE m1 ADD INDEX (c1);
 UNLOCK TABLES;
 DROP TABLE m1, t1;
 
+--echo #
+--echo # If children are to be altered, they need an explicit lock.
+--echo #
+CREATE TABLE t1 (c1 INT);
+CREATE TABLE m1 (c1 INT) ENGINE=MRG_MyISAM UNION=(t1);
+LOCK TABLE m1 WRITE;
+--error ER_TABLE_NOT_LOCKED_FOR_WRITE
+ALTER TABLE t1 ADD INDEX (c1);
+LOCK TABLE m1 WRITE, t1 WRITE;
+ALTER TABLE t1 ADD INDEX (c1);
+UNLOCK TABLES;
+DROP TABLE m1, t1;
 
 --echo #
 --echo # Test for bug #37371 "CREATE TABLE LIKE merge loses UNION parameter"

mysys/my_delete.c

@@ -93,23 +93,33 @@ int nt_share_delete(const char *name, myf MyFlags)
                            name, buf, errno));
     break;
   }
-  
+
   if (errno == ERROR_FILE_NOT_FOUND)
   {
-       my_errno= ENOENT;    // marking, that `name' doesn't exist 
+    my_errno= ENOENT;    // marking, that `name' doesn't exist 
   }
   else if (errno == 0)
   {
-       if (DeleteFile(buf))
-            DBUG_RETURN(0);
-       else if ((my_errno= GetLastError()) == 0)
-            my_errno= ENOENT; // marking, that `buf' doesn't exist
-  } else
-       my_errno= errno;
-  
+    if (DeleteFile(buf))
+      DBUG_RETURN(0);
+    /*
+      The below is more complicated than necessary. For some reason, the
+      assignment to my_errno clears the error number, which is retrieved
+      by GetLastError() (VC2005EE). Assigning to errno first, allows to
+      retrieve the correct value.
+    */
+    errno= GetLastError();
+    if (errno == 0)
+      my_errno= ENOENT; // marking, that `buf' doesn't exist
+    else
+      my_errno= errno;
+  }
+  else
+    my_errno= errno;
+
   if (MyFlags & (MY_FAE+MY_WME))
-       my_error(EE_DELETE, MYF(ME_BELL + ME_WAITTANG + (MyFlags & ME_NOINPUT)),
-                name, my_errno);
+    my_error(EE_DELETE, MYF(ME_BELL + ME_WAITTANG + (MyFlags & ME_NOINPUT)),
+             name, my_errno);
   DBUG_RETURN(-1);
 }
 #endif

mysys/my_mmap.c

@@ -38,13 +38,16 @@ void *my_mmap(void *addr, size_t len, int prot,
   HANDLE hFileMap;
   LPVOID ptr;
   HANDLE hFile= (HANDLE)my_get_osfhandle(fd);
+  DBUG_ENTER("my_mmap");
+  DBUG_PRINT("mysys", ("map fd: %d", fd));
+
   if (hFile == INVALID_HANDLE_VALUE)
-    return MAP_FAILED;
+    DBUG_RETURN(MAP_FAILED);
 
   hFileMap=CreateFileMapping(hFile, &mmap_security_attributes,
                              PAGE_READWRITE, 0, (DWORD) len, NULL);
   if (hFileMap == 0)
-    return MAP_FAILED;
+    DBUG_RETURN(MAP_FAILED);
 
   ptr=MapViewOfFile(hFileMap,
                     prot & PROT_WRITE ? FILE_MAP_WRITE : FILE_MAP_READ,
@@ -59,14 +62,19 @@ void *my_mmap(void *addr, size_t len, int prot,
   CloseHandle(hFileMap);
 
   if (ptr)
-    return ptr;
+  {
+    DBUG_PRINT("mysys", ("mapped addr: %p", ptr));
+    DBUG_RETURN(ptr);
+  }
 
-  return MAP_FAILED;
+  DBUG_RETURN(MAP_FAILED);
 }
 
 int my_munmap(void *addr, size_t len)
 {
-  return UnmapViewOfFile(addr) ? 0 : -1;
+  DBUG_ENTER("my_munmap");
+  DBUG_PRINT("mysys", ("unmap addr: %p", addr));
+  DBUG_RETURN(UnmapViewOfFile(addr) ? 0 : -1);
 }
 
 int my_msync(int fd, void *addr, size_t len, int flags)

sql/item_func.cc

@@ -51,6 +51,7 @@
 #include "sp_rcontext.h"
 #include "sp.h"
 #include "set_var.h"
+#include "debug_sync.h"
 
 #ifdef NO_EMBEDDED_ACCESS_CHECKS
 #define sp_restore_security_context(A,B) while (0) {}
@@ -1941,6 +1942,8 @@ double Item_func_pow::val_real()
 double Item_func_acos::val_real()
 {
   DBUG_ASSERT(fixed == 1);
+  /* One can use this to defer SELECT processing. */
+  DEBUG_SYNC(current_thd, "before_acos_function");
   // the volatile's for BUG #2338 to calm optimizer down (because of gcc's bug)
   volatile double value= args[0]->val_real();
   if ((null_value=(args[0]->null_value || (value < -1.0 || value > 1.0))))

sql/sql_table.cc

@@ -4882,6 +4882,7 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
       if (wait_while_table_is_used(thd, table->table,
                                    HA_EXTRA_PREPARE_FOR_RENAME))
         goto err;
+      DEBUG_SYNC(thd, "after_admin_flush");
       /* Flush entries in the query cache involving this table. */
       query_cache_invalidate3(thd, table->table, 0);
       /*
@@ -5149,7 +5150,11 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
     {
       if (table->table->s->tmp_table)
       {
-        if (open_for_modify)
+        /*
+          If the table was not opened successfully, do not try to get
+          status information. (Bug#47633)
+        */
+        if (open_for_modify && !open_error)
           table->table->file->info(HA_STATUS_CONST);
       }
       else if (open_for_modify || fatal_error)

storage/myisam/mi_check.c

@@ -1736,6 +1736,21 @@ int mi_repair(MI_CHECK *param, register MI_INFO *info,
     {
       mysql_file_close(new_file, MYF(0));
       info->dfile=new_file= -1;
+      /*
+        On Windows, the old data file cannot be deleted if it is either
+        open, or memory mapped. Closing the file won't remove the memory
+        map implicilty on Windows. We closed the data file, but we keep
+        the MyISAM table open. A memory map will be closed on the final
+        mi_close() only. So we need to unmap explicitly here. After
+        renaming the new file under the hook, we couldn't use the map of
+        the old file any more anyway.
+      */
+      if (info->s->file_map)
+      {
+        (void) my_munmap((char*) info->s->file_map,
+                         (size_t) info->s->mmaped_length);
+        info->s->file_map= NULL;
+      }
       if (change_to_newfile(share->data_file_name,MI_NAME_DEXT,
 			    DATA_TMP_EXT, share->base.raid_chunks,
 			    (param->testflag & T_BACKUP_DATA ?

storage/myisammrg/ha_myisammrg.cc

@@ -103,6 +103,7 @@
 #include "myrg_def.h"
 #include "thr_malloc.h"                         // int_sql_alloc
 #include "sql_class.h"                          // THD
+#include "debug_sync.h"
 
 static handler *myisammrg_create_handler(handlerton *hton,
                                          TABLE_SHARE *table,
@@ -755,6 +756,7 @@ int ha_myisammrg::attach_children(void)
   /* Must not call this with attached children. */
   DBUG_ASSERT(!this->file->children_attached);
 
+  DEBUG_SYNC(current_thd, "before_myisammrg_attach");
   /* Must call this with children list in place. */
   DBUG_ASSERT(this->table->pos_in_table_list->next_global == this->children_l);