* cygwin.din (dup3): Export.

	(pipe2): Export.
	* dtable.cc (dtable::dup_worker): Take additional flags parameter.
	Handle O_CLOEXEC flag.
	(dtable::dup3): Rename from dup2.  Take additional flags parameter.
	Check for valid flags.  Drop check for newfd == oldfd.
	* dtable.h (dtable::dup_worker): Add flags parameter.
	(dtable::dup3): Rename from dup2.
	* fcntl.cc (fcntl64): Add F_DUPFD_CLOEXEC case.
	* fhandler.h (fhandler_mailslot::get_object_attr): Add flags parameter.
	* fhandler.cc (fhandler_base::open): Use security attribute with
	inheritance according to setting of O_CLOEXEC flag.
	* fhandler_console.cc (fhandler_console::open): Ditto.
	* fhandler_fifo.cc (sec_user_cloexec): New inline function to
	create security attribute with inheritance according to setting of
	O_CLOEXEC flag.
	(fhandler_fifo::open): Call sec_user_cloexec to fetch security
	attribute.
	(fhandler_fifo::wait): Ditto.
	* fhandler_mem.cc (fhandler_dev_mem::open): Ditto.
	* fhandler_mailslot.cc (fhandler_mailslot::get_object_attr): Take
	additional flags parameter.  Use security attribute with inheritance
	according to setting of O_CLOEXEC flag.
	(fhandler_mailslot::open): Call get_object_attr with flags parameter.
	* fhandler_registry.cc (fhandler_registry::open): Call set_close_on_exec
	on real handles to accommodate O_CLOEXEC flag.
	* fhandler_tty.cc (fhandler_tty_slave::open): Ditto.
	* fhandler_tape.cc: Create mutex with inheritance according to setting
	of O_CLOEXEC flag.
	* pipe.cc: Replace usage of O_NOINHERIT with O_CLOEXEC.
	 (fhandler_pipe::init): Simplify setting close_on_exec flag.
	(fhandler_pipe::open): Remove setting close_on_exec flag.
	(fhandler_pipe::create): Use security attribute with inheritance
	according to setting of O_CLOEXEC flag.
	(pipe2): New exported function.
	* posix_ipc.cc: Throughout, open backing files with O_CLOEXEC
	flag to follow POSIX semantics.
	* security.h (sec_none_cloexec): New define.
	* syscalls.cc (dup): Add missing extern "C" qualifier.  Accommodate
	renaming of dtable::dup2 to dtable::dup3.
	(dup2): Ditto.  Check newfd == oldfd here.
	(dup3): New function.  Check newfd == oldfd here.
	(open): Set close_on_exec flag according to O_CLOEXEC flag before
	calling fhandler->open.
	* include/cygwin/version.h (CYGWIN_VERSION_API_MINOR): Bump.

1 files changed, 48 insertions, 12 deletions

diff --git a/winsup/cygwin/syscalls.cc b/winsup/cygwin/syscalls.cc
index ec589712a..bd3308a42 100644
--- a/winsup/cygwin/syscalls.cc
+++ b/winsup/cygwin/syscalls.cc
@@ -116,13 +116,13 @@ close_all_files (bool norelease)
   cygheap->fdtab.unlock ();
 }
 
-int
+extern "C" int
 dup (int fd)
 {
-  return cygheap->fdtab.dup2 (fd, cygheap_fdnew ());
+  return cygheap->fdtab.dup3 (fd, cygheap_fdnew (), 0);
 }
 
-int
+extern "C" int
 dup2 (int oldfd, int newfd)
 {
   if (newfd >= OPEN_MAX_MAX)
@@ -131,7 +131,39 @@ dup2 (int oldfd, int newfd)
       set_errno (EBADF);
       return -1;
     }
-  return cygheap->fdtab.dup2 (oldfd, newfd);
+  if (newfd == oldfd)
+    {
+      cygheap_fdget cfd (oldfd);
+      if (cfd < 0)
+	{
+	  syscall_printf ("-1 = dup2 (%d, %d) (oldfd not open)", oldfd, newfd);
+	  return -1;
+	}
+      syscall_printf ("%d = dup2 (%d, %d) (newfd==oldfd)", oldfd, oldfd, newfd);
+      return oldfd;
+    }
+  return cygheap->fdtab.dup3 (oldfd, newfd, 0);
+}
+
+extern "C" int
+dup3 (int oldfd, int newfd, int flags)
+{
+  if (newfd >= OPEN_MAX_MAX)
+    {
+      syscall_printf ("-1 = dup3 (%d, %d, %p) (%d too large)",
+		      oldfd, newfd, flags, newfd);
+      set_errno (EBADF);
+      return -1;
+    }
+  if (newfd == oldfd)
+    {
+      cygheap_fdget cfd (oldfd, false, false);
+      set_errno (cfd < 0 ? EBADF : EINVAL);
+      syscall_printf ("-1 = dup3 (%d, %d, %p) (newfd==oldfd)",
+		      oldfd, newfd, flags);
+      return -1;
+    }
+  return cygheap->fdtab.dup3 (oldfd, newfd, flags);
 }
 
 static char desktop_ini[] =
@@ -1037,16 +1069,20 @@ open (const char *unix_path, int flags, ...)
 	      delete fh;
 	      res = -1;
 	    }
-	  else if (!fh->open (flags, (mode & 07777) & ~cygheap->umask))
-	    {
-	      delete fh;
-	      res = -1;
-	    }
 	  else
 	    {
-	      cygheap->fdtab[fd] = fh;
-	      if ((res = fd) <= 2)
-		set_std_handle (res);
+	      fh->close_on_exec (flags & O_CLOEXEC);
+	      if (!fh->open (flags, (mode & 07777) & ~cygheap->umask))
+		{
+		  delete fh;
+		  res = -1;
+		}
+	      else
+		{
+		  cygheap->fdtab[fd] = fh;
+		  if ((res = fd) <= 2)
+		    set_std_handle (res);
+		}
 	    }
 	}
     }