From: Christopher Faylor <me@cgf.cx>
Date: Wed, 1 Feb 2012 17:20:02 +0000 (+0000)
Subject: * dtable.cc (dtable::dup_worker): Add comment explaining why refcnt isn't
X-Git-Tag: sid-snapshot-20120301~89
X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=8fa8b3a3891165dc4c8eb8f05923a3352b20aec3;p=newlib-cygwin.git

* dtable.cc (dtable::dup_worker): Add comment explaining why refcnt isn't
incremented here.
(dtable::dup3): Simplify slightly.  Add comment.
* syscalls.cc (dup3): Increment refcnt here, similarly to dup2.
---

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 384c99be5..a774fee02 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,10 @@
+2012-02-01  Christopher Faylor  <me.cygwin2012@cgf.cx>
+
+	* dtable.cc (dtable::dup_worker): Add comment explaining why refcnt
+	isn't incremented here.
+	(dtable::dup3): Simplify slightly.  Add comment.
+	* syscalls.cc (dup3): Increment refcnt here, similarly to dup2.
+
 2012-02-01  Christopher Faylor  <me.cygwin2012@cgf.cx>
 
 	* fhandler.cc (fhandler_base_overlapped::has_ongoing_io): Don't block
diff --git a/winsup/cygwin/dtable.cc b/winsup/cygwin/dtable.cc
index ba0045f9e..c0af76961 100644
--- a/winsup/cygwin/dtable.cc
+++ b/winsup/cygwin/dtable.cc
@@ -669,8 +669,12 @@ dtable::dup_worker (fhandler_base *oldfh, int flags)
 	}
       else
 	{
+	  /* Don't increment refcnt here since we don't know if this is a
+	     allocated fd.  So we leave this chore to the caller. */
+
 	  newfh->usecount = 0;
 	  newfh->archetype_usecount (1);
+
 	  /* The O_CLOEXEC flag enforces close-on-exec behaviour. */
 	  newfh->set_close_on_exec (!!(flags & O_CLOEXEC));
 	  debug_printf ("duped '%s' old %p, new %p", oldfh->get_name (), oldfh->get_io_handle (), newfh->get_io_handle ());
@@ -735,9 +739,9 @@ dtable::dup3 (int oldfd, int newfd, int flags)
 
   if (!not_open (newfd))
     close (newfd);
-  else if ((size_t) newfd < size)
-    /* nothing to do */;
-  else if (find_unused_handle (newfd) < 0)
+  else if ((size_t) newfd > size
+	   && find_unused_handle (newfd) < 0)
+    /* couldn't extend fdtab */
     {
       newfh->close ();
       res = -1;
diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index 4ff64a3e3..3ed0f4f95 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -161,8 +161,9 @@ dup3 (int oldfd, int newfd, int flags)
       set_errno (cfd < 0 ? EBADF : EINVAL);
       res = -1;
     }
-  else
-    res = cygheap->fdtab.dup3 (oldfd, newfd, flags);
+  else if ((res = cygheap->fdtab.dup3 (oldfd, newfd, flags)) == newfd)
+    cygheap->fdtab[newfd]->refcnt (1);
+
   syscall_printf ("%R = dup3(%d, %d, %p)", res, oldfd, newfd, flags);
   return res;
 }