* external.cc (cygwin_internal): Export __cygwin_user_data.

* include/sys/cygwin.h: Allow definition of per_process even when not compiling
with C++.
(cygwin_getinfo_types): Add CW_USER_DATA.
* lib/_cygwin_crt0_common.cc (_cygwin_crt0_common): Get __cygwin_user_data
pointer from cygwin_internal.  If it doesn't exist, return failure.  Use either
this pointer or passed in pointer throughout.  Clear forkee.
* lib/crt0.h: Accomodate argument changes to _cygwin_crt0_common.
* lib/cygwin_attach_dll.c (cygwin_attach_dll): Reorganize to allow use of newer
binaries with older DLLs.  Detect older DLLs when _cygwin_crt0_common returns 0
and allocate space for a per_process structure on the stack.
* lib/cygwin_crt0.c (cygwin_crt0): Ditto.

1 files changed, 11 insertions, 2 deletions

diff --git a/winsup/cygwin/lib/cygwin_attach_dll.c b/winsup/cygwin/lib/cygwin_attach_dll.c
index 18d9d7fad..09b898bdf 100644
--- a/winsup/cygwin/lib/cygwin_attach_dll.c
+++ b/winsup/cygwin/lib/cygwin_attach_dll.c
@@ -8,15 +8,24 @@ This software is a copyrighted work licensed under the terms of the
 Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
 details. */
 
+#undef __INSIDE_CYGWIN__
 #include <windows.h>
+#include <sys/cygwin.h>
 #include "crt0.h"
 
 /* for a loaded dll */
 int
 cygwin_attach_dll (HMODULE h, MainFunc f)
 {
-  _cygwin_crt0_common (f);
+  struct per_process *u;
+  if (_cygwin_crt0_common (f, NULL))
+    u = NULL;		/* Newer DLL.  Use DLL internal per_process. */
+  else			/* Older DLL.  Provide a per_process */
+    {
+      u = (struct per_process *) alloca (sizeof (*u));
+      (void) _cygwin_crt0_common (f, u);
+    }
 
   /* jump into the dll. */
-  return dll_dllcrt0 (h, NULL);
+  return dll_dllcrt0 (h, u);
 }