+2013-02-14 Paul Eggert <eggert@cs.ucla.edu>
+
+ putenv: fix heap corruption with mixed putenv/_putenv
+ Problem reported by Michael Goffioul in
+ <http://lists.gnu.org/archive/html/bug-gnulib/2013-02/msg00061.html>.
+ * lib/putenv.c (putenv) [HAVE__PUTENV]:
+ Rely on _putenv to allocate the new environment.
+ * m4/putenv.m4 (gl_PREREQ_PUTENV): New macro.
+ * modules/putenv (configure.ac): Use it.
+
2013-02-11 Paul Eggert <eggert@cs.ucla.edu>
unsetenv etc.: port to Solaris 11 + GNU Emacs
if (*ep == NULL)
{
+#if HAVE__PUTENV
+ /* Rely on _putenv to allocate the new environment. If other
+ parts of the application use _putenv, the !HAVE__PUTENV code
+ would fight over who owns the environ vector, causing a crash. */
+ if (name_end[1])
+ return _putenv (string);
+ else
+ {
+ /* _putenv ("NAME=") unsets NAME, so invoke _putenv ("NAME=x")
+ to allocate the environ vector and then replace the new
+ entry with "NAME=". */
+ int putenv_result, putenv_errno;
+ char *name_x = malloc (name_end - string + sizeof "=x");
+ if (!name_x)
+ return -1;
+ memcpy (name_x, string, name_end - string + 1);
+ name_x[name_end - string + 1] = 'x';
+ name_x[name_end - string + 2] = 0;
+ putenv_result = _putenv (name_x);
+ putenv_errno = errno;
+ for (ep = environ; *ep; ep++)
+ if (*ep == name_x)
+ {
+ *ep = string;
+ break;
+ }
+ free (name_x);
+ __set_errno (putenv_errno);
+ return putenv_result;
+ }
+#else
static char **last_environ = NULL;
char **new_environ = (char **) malloc ((size + 2) * sizeof (char *));
if (new_environ == NULL)
free (last_environ);
last_environ = new_environ;
environ = new_environ;
+#endif
}
else
*ep = string;
;;
esac
])
+
+# Prerequisites of lib/putenv.c.
+AC_DEFUN([gl_PREREQ_PUTENV],
+[
+ AC_CHECK_FUNCS([_putenv])
+])