(emacs_gnutls_write): Check for GNUTLS_E_AGAIN and not EINTR.

According to the documentation, this is correct, and it seems to
make things work.

src/ChangeLog

@@ -5,6 +5,9 @@
 	(emacs_gnutls_read): Return -1 if we got an error from
 	gnutls_read().  This allows us to actually read lots of data from
 	the GnuTLS stream.
+	(emacs_gnutls_write): Check for GNUTLS_E_AGAIN and not EINTR.
+	According to the documentation, this is correct, and it seems to
+	make things work.
 2010-10-09  Chong Yidong  <cyd@stupidchicken.com>

src/gnutls.c

@@ -86,9 +86,9 @@ emacs_gnutls_write (int fildes, struct Lisp_Process *proc, char *buf,
     {
       rtnval = gnutls_write (state, buf, nbyte);
 
-      if (rtnval == -1)
+      if (rtnval < 0)
         {
-          if (errno == EINTR)
+          if (rtnval == GNUTLS_E_AGAIN || rtnval == GNUTLS_E_INTERRUPTED)
             continue;
           else
             return (bytes_written ? bytes_written : -1);