* shm.cc (shmctl): On IPC_RMID don't unmap views and don't close handle

	if the map is still referenced to emulate Linux and BSD behaviour.

1 files changed, 8 insertions, 10 deletions

diff --git a/winsup/cygwin/shm.cc b/winsup/cygwin/shm.cc
index 27cc9843c..6fb120b6d 100644
--- a/winsup/cygwin/shm.cc
+++ b/winsup/cygwin/shm.cc
@@ -265,22 +265,20 @@ shmctl (int shmid, int cmd, struct shmid_ds *buf)
 	{
 	  if (ssh_entry->shmid == shmid)
 	    {
-	      shm_attached_list *sph_entry, *sph_next_entry;
-	      SLIST_FOREACH_SAFE (sph_entry, &sph_list, sph_next,
-				  sph_next_entry)
+	      bool in_use = false;
+	      shm_attached_list *sph_entry;
+	      SLIST_FOREACH (sph_entry, &sph_list, sph_next)
 		{
 		  if (sph_entry->hdl == ssh_entry->hdl)
 		    {
-		      SLIST_REMOVE (&sph_list, sph_entry, shm_attached_list,
-				    sph_next);
-		      /* ...unmap all views for this handle... */
-		      UnmapViewOfFile (sph_entry->ptr);
-		      delete sph_entry;
+		      in_use = true;
+		      break;
 		    }
 		}
 	      SLIST_REMOVE (&ssh_list, ssh_entry, shm_shmid_list, ssh_next);
-	      /* ...and close the handle. */
-	      CloseHandle (ssh_entry->hdl);
+	      /* ...and close the handle if it's not in use anymore. */
+	      if (!in_use)
+		CloseHandle (ssh_entry->hdl);
 	      delete ssh_entry;
 	      break;
 	    }