Add a null implementation of pledge.

Fixes builds on almost everything.

configure.ac

@@ -854,7 +854,6 @@ mips-sony-bsd|mips-sony-newsos4)
 	AC_DEFINE([SYSLOG_R_SAFE_IN_SIGHAND], [1],
 	    [syslog_r function is safe to use in in a signal handler])
 	TEST_MALLOC_OPTIONS="AFGJPRX"
-	AC_CHECK_FUNCS([pledge])
 	;;
 *-*-solaris*)
 	if test "x$withval" != "xno" ; then
@@ -1669,6 +1668,7 @@ AC_CHECK_FUNCS([ \
 	nsleep \
 	ogetaddrinfo \
 	openlog_r \
+	pledge \
 	poll \
 	prctl \
 	pstat \

openbsd-compat/bsd-misc.c

@@ -276,3 +276,11 @@ getpgid(pid_t pid)
 	return -1;
 }
 #endif
+
+#ifndef HAVE_PLEDGE
+int
+pledge(const char *promises, const char *paths[])
+{
+	return 0;
+}
+#endif

openbsd-compat/bsd-misc.h

@@ -122,4 +122,8 @@ pid_t getpgid(pid_t);
 # define krb5_free_error_message(a,b) do { } while(0)
 #endif
 
+#ifndef HAVE_PLEDGE
+int pledge(const char *promises, const char *paths[]);
+#endif
+
 #endif /* _BSD_MISC_H */