[newlib-cygwin] Cygwin: FIFO: make certain errors non-fatal

[Ken Brown]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=d3a01b7ec253db6cf9b3dc2be4dd80a9da01281e

commit d3a01b7ec253db6cf9b3dc2be4dd80a9da01281e
Author: Ken Brown <kbrown@cornell.edu>
Date:   Sat Jul 11 15:20:45 2020 -0400

    Cygwin: FIFO: make certain errors non-fatal
    
    If update_my_handlers fails to duplicate one or more handles, just
    mark the corresponding handlers as being in an error state.
    
    But if update_my_handlers is unable to open the process of the
    previous owner, it's likely that something serious has gone wrong, so
    we continue to make that a fatal error.

Diff:
---
 winsup/cygwin/fhandler_fifo.cc | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/winsup/cygwin/fhandler_fifo.cc b/winsup/cygwin/fhandler_fifo.cc
index 69dda0811..91a276ee9 100644
--- a/winsup/cygwin/fhandler_fifo.cc
+++ b/winsup/cygwin/fhandler_fifo.cc
@@ -383,11 +383,7 @@ fhandler_fifo::update_my_handlers ()
   else
     prev_proc = OpenProcess (PROCESS_DUP_HANDLE, false, prev.winpid);
   if (!prev_proc)
-    {
-      debug_printf ("Can't open process of previous owner, %E");
-      __seterrno ();
-      goto out;
-    }
+    api_fatal ("Can't open process of previous owner, %E");
 
   for (int i = 0; i < get_shared_nhandlers (); i++)
     {
@@ -399,14 +395,17 @@ fhandler_fifo::update_my_handlers ()
 			    !close_on_exec (), DUPLICATE_SAME_ACCESS))
 	{
 	  debug_printf ("Can't duplicate handle of previous owner, %E");
-	  --nhandlers;
 	  __seterrno ();
-	  goto out;
+	  fc.state = fc_error;
+	  fc.last_read = false;
+	  ret = -1;
+	}
+      else
+	{
+	  fc.state = shared_fc_handler[i].state;
+	  fc.last_read = shared_fc_handler[i].last_read;
 	}
-      fc.state = shared_fc_handler[i].state;
-      fc.last_read = shared_fc_handler[i].last_read;
     }
-out:
   set_prev_owner (null_fr_id);
   return ret;
 }
@@ -493,7 +492,7 @@ fhandler_fifo::fifo_reader_thread_func ()
 	      set_owner (me);
 	      set_pending_owner (null_fr_id);
 	      if (update_my_handlers () < 0)
-		api_fatal ("Can't update my handlers, %E");
+		debug_printf ("error updating my handlers, %E");
 	      owner_found ();
 	      owner_unlock ();
 	      /* Fall through to owner_listen. */