bk commit into 4.0 tree (monty:1.2031)

[monty]

Below is the list of changes that have just been committed into a local
4.0 repository of monty. When monty does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
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ChangeSet
  1.2031 05/01/15 03:47:06 monty@stripped +3 -0
  Fixed possible access to unintialized memory in filesort when using many buffers

  sql/filesort.cc
    1.58 05/01/15 03:47:03 monty@stripped +2 -0
    Tell that io_cache is moved

  mysys/mf_iocache.c
    1.40 05/01/15 03:47:03 monty@stripped +35 -14
    Added function to call if IO_CACHE is moved

  include/my_sys.h
    1.110 05/01/15 03:47:03 monty@stripped +1 -0
    Added function to call if IO_CACHE is moved

# 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:	monty
# Host:	narttu.mysql.fi
# Root:	/home/my/mysql-4.0

--- 1.109/include/my_sys.h	2004-08-19 21:24:32 +03:00
+++ 1.110/include/my_sys.h	2005-01-15 03:47:03 +02:00
@@ -671,6 +671,7 @@
 extern my_bool reinit_io_cache(IO_CACHE *info,enum cache_type type,
 			       my_off_t seek_offset,pbool use_async_io,
 			       pbool clear_cache);
+extern void setup_io_cache(IO_CACHE* info);
 extern int _my_b_read(IO_CACHE *info,byte *Buffer,uint Count);
 #ifdef THREAD
 extern int _my_b_read_r(IO_CACHE *info,byte *Buffer,uint Count);

--- 1.39/mysys/mf_iocache.c	2004-03-25 12:21:58 +02:00
+++ 1.40/mysys/mf_iocache.c	2005-01-15 03:47:03 +02:00
@@ -71,9 +71,40 @@
 #define IO_ROUND_UP(X) (((X)+IO_SIZE-1) & ~(IO_SIZE-1))
 #define IO_ROUND_DN(X) ( (X)            & ~(IO_SIZE-1))
 
+
+/*
+  Setup internal pointers inside IO_CACHE
+
+  SYNOPSIS
+    setup_io_cache()
+    info		IO_CACHE handler
+
+  NOTES
+    This is called on automaticly on init or reinit of IO_CACHE
+    It must be called externally if one moves or copies an IO_CACHE
+    object.
+*/
+
+void setup_io_cache(IO_CACHE* info)
+{
+  /* Ensure that my_b_tell() and my_b_bytes_in_cache works */
+  if (info->type == WRITE_CACHE)
+  {
+    info->current_pos= &info->write_pos;
+    info->current_end= &info->write_end;
+  }
+  else
+  {
+    info->current_pos= &info->read_pos;
+    info->current_end= &info->read_end;
+  }
+}
+
+
 static void
-init_functions(IO_CACHE* info, enum cache_type type)
+init_functions(IO_CACHE* info)
 {
+  enum cache_type type= info->type;
   switch (type) {
   case READ_NET:
     /*
@@ -97,17 +128,7 @@
     info->write_function = _my_b_write;
   }
 
-  /* Ensure that my_b_tell() and my_b_bytes_in_cache works */
-  if (type == WRITE_CACHE)
-  {
-    info->current_pos= &info->write_pos;
-    info->current_end= &info->write_end;
-  }
-  else
-  {
-    info->current_pos= &info->read_pos;
-    info->current_end= &info->read_end;
-  }
+  setup_io_cache(info);
 }
 
 	/*
@@ -211,7 +232,7 @@
   /* End_of_file may be changed by user later */
   info->end_of_file= end_of_file;
   info->error=0;
-  init_functions(info,type);
+  init_functions(info);
 #ifdef HAVE_AIOWAIT
   if (use_async_io && ! my_disable_async_io)
   {
@@ -333,7 +354,7 @@
   }
   info->type=type;
   info->error=0;
-  init_functions(info,type);
+  init_functions(info);
 
 #ifdef HAVE_AIOWAIT
   if (use_async_io && ! my_disable_async_io &&

--- 1.57/sql/filesort.cc	2003-12-30 13:14:18 +02:00
+++ 1.58/sql/filesort.cc	2005-01-15 03:47:03 +02:00
@@ -680,6 +680,8 @@
     if (flush_io_cache(to_file))
       break;					/* purecov: inspected */
     temp=from_file; from_file=to_file; to_file=temp;
+    setup_io_cache(from_file);
+    setup_io_cache(to_file);
     *maxbuffer= (uint) (lastbuff-buffpek)-1;
   }
   close_cached_file(to_file);			// This holds old result