test-skeleton: Kill any child process's offspring

This makes sure any subprocesses created by the program being tested get
killed as well if their parent times out.  Otherwise if they are really
stuck, they may remain there running forever after the test case and
then the whole test suite has completed, until killed by hand.

	* test-skeleton.c (signal_handler): Kill the whole process group
	before killing the child individually.
	(main): Report any failure on `setpgid'.

ChangeLog

@@ -1,3 +1,10 @@
+2014-06-30  Maciej W. Rozycki  <macro@codesourcery.com>
+	    Roland McGrath <roland@hack.frob.com>
+
+	* test-skeleton.c (signal_handler): Kill the whole process group
+	before killing the child individually.
+	(main): Report any failure on `setpgid'.
+
 2014-06-30  Roland McGrath  <roland@hack.frob.com>
 
 	* sysdeps/arm/nptl/tls.h: Rename the multiple inclusion guard

test-skeleton.c

@@ -17,6 +17,7 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <getopt.h>
@@ -138,7 +139,10 @@ signal_handler (int sig __attribute__ ((unused)))
   int killed;
   int status;
 
-  /* Send signal.  */
+  assert (pid > 1);
+  /* Kill the whole process group.  */
+  kill (-pid, SIGKILL);
+  /* In case setpgid failed in the child, kill it individually too.  */
   kill (pid, SIGKILL);
 
   /* Wait for it to terminate.  */
@@ -342,7 +346,8 @@ main (int argc, char *argv[])
 
       /* We put the test process in its own pgrp so that if it bogusly
 	 generates any job control signals, they won't hit the whole build.  */
-      setpgid (0, 0);
+      if (setpgid (0, 0) != 0)
+	printf ("Failed to set the process group ID: %m\n");
 
       /* Execute the test function and exit with the return value.   */
       exit (TEST_FUNCTION);