Merge mysql.com:/home/hf/work/mysql-5.0.clean

into  mysql.com:/home/hf/work/mysql-5.1.clean

1 files changed, 34 insertions, 7 deletions

diff --git a/sql/filesort.cc b/sql/filesort.cc
index 01f3bb97557..df84787372d 100644
--- a/sql/filesort.cc
+++ b/sql/filesort.cc
@@ -115,6 +115,8 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
   DBUG_PUSH("");		/* No DBUG here */
 #endif
   FILESORT_INFO table_sort;
+  TABLE_LIST *tab= table->pos_in_table_list;
+  Item_subselect *subselect= tab ? tab->containing_subselect() : 0;
   /* 
     Don't use table->sort in filesort as it is also used by 
     QUICK_INDEX_MERGE_SELECT. Work with a copy and put it back at the end 
@@ -127,7 +129,6 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
   my_b_clear(&tempfile);
   my_b_clear(&buffpek_pointers);
   buffpek=0;
-  sort_keys= (uchar **) NULL;
   error= 1;
   bzero((char*) &param,sizeof(param));
   param.sort_length= sortlength(thd, sortorder, s_length, &multi_byte_charset);
@@ -208,13 +209,15 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
     ulong old_memavl;
     ulong keys= memavl/(param.rec_length+sizeof(char*));
     param.keys=(uint) min(records+1, keys);
-    if ((sort_keys= (uchar **) make_char_array(param.keys, param.rec_length,
-					       MYF(0))))
+    if (table_sort.sort_keys ||
+        (table_sort.sort_keys= (uchar **) make_char_array(param.keys, param.rec_length,
+                                               MYF(0))))
       break;
     old_memavl=memavl;
     if ((memavl=memavl/4*3) < min_sort_memory && old_memavl > min_sort_memory)
       memavl= min_sort_memory;
   }
+  sort_keys= table_sort.sort_keys;
   if (memavl < min_sort_memory)
   {
     my_error(ER_OUTOFMEMORY,MYF(ME_ERROR+ME_WAITTANG),
@@ -241,8 +244,12 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
   }
   else
   {
-    if (!(buffpek=read_buffpek_from_file(&buffpek_pointers, maxbuffer)))
+    if (!table_sort.buffpek && table_sort.buffpek_len < maxbuffer &&
+        !(table_sort.buffpek=
+          (byte *) read_buffpek_from_file(&buffpek_pointers, maxbuffer)))
       goto err;
+    buffpek= (BUFFPEK *) table_sort.buffpek;
+    table_sort.buffpek_len= maxbuffer;
     close_cached_file(&buffpek_pointers);
 	/* Open cached file if it isn't open */
     if (! my_b_inited(outfile) &&
@@ -275,8 +282,14 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
  err:
   if (param.tmp_buffer)
     x_free(param.tmp_buffer);
-  x_free((gptr) sort_keys);
-  x_free((gptr) buffpek);
+  if (!subselect || !subselect->is_uncacheable())
+  {
+    x_free((gptr) sort_keys);
+    table_sort.sort_keys= 0;
+    x_free((gptr) buffpek);
+    table_sort.buffpek= 0;
+    table_sort.buffpek_len= 0;
+  }
   close_cached_file(&tempfile);
   close_cached_file(&buffpek_pointers);
   if (my_b_inited(outfile))
@@ -307,13 +320,27 @@ ha_rows filesort(THD *thd, TABLE *table, SORT_FIELD *sortorder, uint s_length,
 } /* filesort */
 
 
-void filesort_free_buffers(TABLE *table)
+void filesort_free_buffers(TABLE *table, bool full)
 {
   if (table->sort.record_pointers)
   {
     my_free((gptr) table->sort.record_pointers,MYF(0));
     table->sort.record_pointers=0;
   }
+  if (full)
+  {
+    if (table->sort.sort_keys )
+    {
+      x_free((gptr) table->sort.sort_keys);
+      table->sort.sort_keys= 0;
+    }
+    if (table->sort.buffpek)
+    {
+      x_free((gptr) table->sort.buffpek);
+      table->sort.buffpek= 0;
+      table->sort.buffpek_len= 0;
+    }
+  }
   if (table->sort.addon_buf)
   {
     my_free((char *) table->sort.addon_buf, MYF(0));