1 files changed, 77 insertions, 0 deletions
diff --git a/hurd/ctty-input.c b/hurd/ctty-input.c
new file mode 100644
index 0000000000..71aef1b6cf
--- /dev/null
+++ b/hurd/ctty-input.c
@@ -0,0 +1,77 @@
+/* _hurd_ctty_input -- Do an input RPC and generate SIGTTIN if necessary.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <hurd.h>
+#include <hurd/signal.h>
+
+/* Call *RPC on PORT and/or CTTY.  If a call on CTTY returns EBACKGROUND,
+   generate SIGTTIN or EIO as appropriate.  */
+
+error_t
+_hurd_ctty_input (io_t port, io_t ctty, error_t (*rpc) (io_t))
+{
+  error_t err;
+
+  do
+    {
+      err = (*rpc) (ctty != MACH_PORT_NULL ? ctty : port);
+      if (ctty != MACH_PORT_NULL && err == EBACKGROUND)
+	{
+	  /* We are a background job and tried to read from the tty.
+	     We should probably get a SIGTTIN signal.  */
+	  struct hurd_sigstate *ss;
+	  if (_hurd_orphaned)
+	    /* Our process group is orphaned.  Don't stop; just fail.  */
+	    err = EIO;
+	  else
+	    {
+	      ss = _hurd_self_sigstate ();
+	      __spin_lock (&ss->lock);
+	      if (__sigismember (&ss->blocked, SIGTTIN) ||
+		  ss->actions[SIGTTIN].sa_handler == SIG_IGN)
+		/* We are blocking or ignoring SIGTTIN.  Just fail.  */
+		err = EIO;
+	      __spin_unlock (&ss->lock);
+	    }
+	  if (err == EBACKGROUND)
+	    {
+	      /* Send a SIGTTIN signal to our process group.
+		 
+		 We must remember here not to clobber ERR, since
+		 the loop condition below uses it to recall that
+		 we should retry after a stop.  */
+
+	      __USEPORT (CTTYID, _hurd_sig_post (0, SIGTTIN, port));
+	      /* XXX what to do if error here? */
+
+	      /* At this point we should have just run the handler for
+		 SIGTTIN or resumed after being stopped.  Now this is
+		 still a "system call", so check to see if we should
+		 restart it.  */
+	      __spin_lock (&ss->lock);
+	      if (!(ss->actions[SIGTTIN].sa_flags & SA_RESTART))
+		err = EINTR;
+	      __spin_unlock (&ss->lock);
+	    }
+	}
+      /* If the last RPC generated a SIGTTIN, loop to try it again.  */
+    } while (err == EBACKGROUND);
+
+  return err;
+}