Fixed memory allocation in Unique to not allocate too much memory

myisam/mi_info.c:
  Updated comments
mysys/tree.c:
  Added comment
sql/net_serv.cc:
  Added comment

myisam/mi_info.c

@@ -80,15 +80,17 @@ int mi_status(MI_INFO *info, register MI_ISAMINFO *x, uint flag)
 			(HA_OPTION_PACK_RECORD | HA_OPTION_COMPRESS_RECORD)) ?
 		       0L : share->base.pack_reclength);
     x->sortkey= -1;				/* No clustering */
-    /* The following should be included even if we are not compiling with
-       USE_RAID as the client must be able to request it! */
     x->rec_per_key	= share->state.rec_per_key_part;
-    x->raid_type= share->base.raid_type;
-    x->raid_chunks= share->base.raid_chunks;
-    x->raid_chunksize= share->base.raid_chunksize;
     x->key_map	 	= share->state.key_map;
     x->data_file_name   = share->data_file_name;
     x->index_file_name  = share->index_file_name;
+    /*
+      The following should be included even if we are not compiling with
+      USE_RAID as the client must be able to request it!
+    */
+    x->raid_type= share->base.raid_type;
+    x->raid_chunks= share->base.raid_chunks;
+    x->raid_chunksize= share->base.raid_chunksize;
   }
   if ((flag & HA_STATUS_TIME) && !my_fstat(info->dfile,&state,MYF(0)))
     x->update_time=state.st_mtime;

mysys/tree.c

@@ -90,6 +90,11 @@ void init_tree(TREE *tree, uint default_alloc_size, uint memory_limit,
   if (!free_element && size >= 0 &&
       ((uint) size <= sizeof(void*) || ((uint) size & (sizeof(void*)-1))))
   {
+    /*
+      We know that the data doesn't have to be aligned (like if the key
+      contains a double), so we can store the data combined with the
+      TREE_ELEMENT.
+    */
     tree->offset_to_key=sizeof(TREE_ELEMENT); /* Put key after element */
     /* Fix allocation size so that we don't lose any memory */
     default_alloc_size/=(sizeof(TREE_ELEMENT)+size);

sql/net_serv.cc

@@ -21,6 +21,9 @@
   Read packets are reallocated dynamicly when reading big packets.
   Each logical packet has the following pre-info:
   3 byte length & 1 byte package-number.
+
+  This file needs to be written in C as it's used by the libmysql client as a
+  C file.
 */
 
 #ifdef __WIN__

sql/sql_class.h

@@ -781,11 +781,12 @@ class Unique :public Sql_alloc
   TREE tree;
   byte *record_pointers;
   bool flush();
+  uint size;
 
 public:
   ulong elements;
   Unique(qsort_cmp2 comp_func, void * comp_func_fixed_arg,
-	 uint size, ulong max_in_memory_size_arg);
+	 uint size_arg, ulong max_in_memory_size_arg);
   ~Unique();
   inline bool unique_add(gptr ptr)
   {
@@ -800,7 +801,8 @@ class Unique :public Sql_alloc
   friend int unique_write_to_ptrs(gptr key, element_count count, Unique *unique);
 };
 
- class multi_delete : public select_result {
+class multi_delete : public select_result
+{
   TABLE_LIST *delete_tables, *table_being_deleted;
   Unique  **tempfiles;
   THD *thd;
@@ -808,7 +810,7 @@ class Unique :public Sql_alloc
   uint num_of_tables;
   int error;
   bool do_delete, transactional_tables, log_delayed, normal_tables;
- public:
+public:
   multi_delete(THD *thd, TABLE_LIST *dt, uint num_of_tables);
   ~multi_delete();
   int prepare(List<Item> &list);
@@ -819,7 +821,7 @@ class Unique :public Sql_alloc
   void send_error(uint errcode,const char *err);
   int  do_deletes (bool from_send_error);
   bool send_eof();
- };
+};
 
 class multi_update : public select_result
 {

sql/uniques.cc

@@ -49,8 +49,8 @@ int unique_write_to_ptrs(gptr key, element_count count, Unique *unique)
 }
 
 Unique::Unique(qsort_cmp2 comp_func, void * comp_func_fixed_arg,
-	       uint size, ulong max_in_memory_size_arg)
-  :max_in_memory_size(max_in_memory_size_arg),elements(0)
+	       uint size_arg, ulong max_in_memory_size_arg)
+  :max_in_memory_size(max_in_memory_size_arg), size(size_arg), elements(0)
 {
   my_b_clear(&file);
   init_tree(&tree, max_in_memory_size / 16, 0, size, comp_func, 0, NULL,
@@ -101,7 +101,7 @@ bool Unique::get(TABLE *table)
   {
     /* Whole tree is in memory;  Don't use disk if you don't need to */
     if ((record_pointers=table->record_pointers= (byte*)
-	 my_malloc(tree.size_of_element * tree.elements_in_tree, MYF(0))))
+	 my_malloc(size * tree.elements_in_tree, MYF(0))))
     {
       (void) tree_walk(&tree, (tree_walk_action) unique_write_to_ptrs,
 		       this, left_root_right);