dll_index NO_COPY patch

[Jason Tishler]

The attached patch fixes the problem described in the following thread:

    http://cygwin.com/ml/cygwin-developers/2002-11/msg00019.html

Given the following facts:

    1. During fork(), fork_copy() is run after
       dll_list::load_after_fork().
    2. The static dll_index variable in include/cygwin/cygwin_dll.h is
       not marked NO_COPY.
    3. The dll structure allocated by dll_list::alloc() is not
       guaranteed to be the same in the parent and child.

I believe that the following is the correct root cause analysis of the
problem:

    When #3 above occurs, fork_copy() overwrites the child's dll_index
    with the parent's value.  This causes dll_list::detach() to access
    unallocated memory which in turn causes the child to stackdump.

Jason

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-------------- next part --------------
Index: include/cygwin/cygwin_dll.h
===================================================================
RCS file: /cvs/src/src/winsup/cygwin/include/cygwin/cygwin_dll.h,v
retrieving revision 1.8
diff -u -p -r1.8 cygwin_dll.h
--- include/cygwin/cygwin_dll.h	11 Sep 2001 20:01:01 -0000	1.8
+++ include/cygwin/cygwin_dll.h	11 Nov 2002 15:23:39 -0000
@@ -12,6 +12,7 @@ details. */
 #define __CYGWIN_CYGWIN_DLL_H__
 
 #include <windows.h>
+#include "winsup.h"
 
 #ifdef __cplusplus
 #define CDECL_BEGIN extern "C" {
@@ -39,7 +40,7 @@ static int __dllMain (int a, char **b, c
   return Entry (storedHandle, storedReason, storedPtr);		              \
 }									      \
 									      \
-static DWORD dll_index;							      \
+static NO_COPY DWORD dll_index;						      \
 									      \
 int WINAPI _cygwin_dll_entry (HINSTANCE h, DWORD reason, void *ptr)	      \
 {									      \
-------------- next part --------------
Mon Nov 11 10:45:37 2002  <jason@tishler.net>

	* include/cygwin/cygwin_dll.h: Add #include "winsup.h".
	(dll_index): Make NO_COPY.