* shared.cc (open_shared): Revert to "old" method for shared memory location if

!wincap.needs_memory_protection.
* wincap.cc: Implement needs_memory_protection throughout.
* wincap.h: Ditto.

1 files changed, 22 insertions, 11 deletions

diff --git a/winsup/cygwin/shared.cc b/winsup/cygwin/shared.cc
index 113e7f5..59ca349 100644
--- a/winsup/cygwin/shared.cc
+++ b/winsup/cygwin/shared.cc
@@ -70,20 +70,15 @@ open_shared (const char *name, int n, HANDLE &shared_h, DWORD size, shared_locat
       + pround (sizeof (_pinfo))
   };
 
-  if (m == SH_CYGWIN_SHARED)
+  void *addr;
+  if (!wincap.needs_memory_protection ())
+    addr = NULL;
+  else
     {
-      for (int i = SH_CYGWIN_SHARED; i < SH_TOTAL_SIZE; i++)
-	if (!VirtualAlloc (offsets[i], offsets[i + 1] - offsets[i],
-			   MEM_RESERVE, PAGE_NOACCESS))
-	  continue;  /* oh well */
-      if (!child_proc_info)
-	for (DWORD s = 0x950000; s <= 0xa40000; s += 0x1000)
-	  VirtualAlloc ((void *) s, 4, MEM_RESERVE, PAGE_NOACCESS);
+      addr = offsets[m];
+      (void) VirtualFree (addr, 0, MEM_RELEASE);
     }
 
-  void *addr = offsets[m];
-  (void) VirtualFree (addr, 0, MEM_RELEASE);
-
   if (!size)
     return addr;
 
@@ -118,6 +113,22 @@ open_shared (const char *name, int n, HANDLE &shared_h, DWORD size, shared_locat
   if (!shared)
     api_fatal ("MapViewOfFileEx '%s'(%p), %E.  Terminating.", name, shared_h);
 
+  if (m == SH_CYGWIN_SHARED)
+    {
+      for (int i = SH_CYGWIN_SHARED + 1; i < SH_TOTAL_SIZE; i++)
+	{
+	  offsets[i] += (char *) shared - offsets[0];
+	  if (!VirtualAlloc (offsets[i], offsets[i + 1] - offsets[i],
+			     MEM_RESERVE, PAGE_NOACCESS))
+	    continue;  /* oh well */
+	  offsets[0] = (char *) shared;
+	}
+
+      if (!child_proc_info && wincap.needs_memory_protection ())
+	for (DWORD s = 0x950000; s <= 0xa40000; s += 0x1000)
+	  VirtualAlloc ((void *) s, 4, MEM_RESERVE, PAGE_NOACCESS);
+    }
+
   debug_printf ("name %s, shared %p (wanted %p), h %p", name, shared, addr, shared_h);
 
   /* FIXME: I couldn't find anywhere in the documentation a note about