unlockpt and EBADF

[Bruno Haible]

Our unit test verifies that unlockpt() checks against an invalid argument.
But gnulib's implementation does not always do this check.


2011-10-20  Bruno Haible  <address@hidden>

        unlockpt: Detect invalid argument.
        * lib/unlockpt.c: Include <fcntl.h>.
        (unlockpt): Check whether fd is valid, using fcntl().
        * modules/unlockpt (Depends-on): Add fcntl-h.

--- lib/unlockpt.c.orig Fri Oct 21 02:20:26 2011
+++ lib/unlockpt.c      Fri Oct 21 02:18:27 2011
@@ -19,6 +19,7 @@
 
 #include <stdlib.h>
 
+#include <fcntl.h>
 #include <unistd.h>
 
 int
@@ -36,6 +37,8 @@
 #else
   /* Assume that the slave side of a pseudo-terminal is already unlocked
      by default.  */
+  if (fcntl (fd, F_GETFD) < 0)
+    return -1;
   return 0;
 #endif
 }
--- modules/unlockpt.orig       Fri Oct 21 02:20:26 2011
+++ modules/unlockpt    Fri Oct 21 02:20:08 2011
@@ -9,6 +9,7 @@
 Depends-on:
 stdlib
 extensions
+fcntl-h         [test $HAVE_UNLOCKPT = 0]
 ptsname         [test $HAVE_UNLOCKPT = 0]
 
 configure.ac:

-- 
In memoriam Eduard Brücklmeier <http://en.wikipedia.org/wiki/Eduard_Brücklmeier>