1 files changed, 115 insertions, 0 deletions
diff --git a/tests/sys/kern/sigaltstack.c b/tests/sys/kern/sigaltstack.c
new file mode 100644
index 000000000000..36d9542e5548
--- /dev/null
+++ b/tests/sys/kern/sigaltstack.c
@@ -0,0 +1,115 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2018 Eric van Gyzen
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <atf-c.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+/*
+ * TODO add tests for:
+ *
+ * - all error cases
+ * - SS_DISABLE
+ * - no effect without SA_ONSTACK
+ */
+
+static sig_atomic_t disabled_correct = 1;
+static sig_atomic_t level1_correct = -1;
+static sig_atomic_t level2_correct = -1;
+
+static void
+sig_handler(int signo, siginfo_t *info __unused, void *ucp)
+{
+	ucontext_t *uc = ucp;
+
+	// The alternate signal stack is enabled.
+	disabled_correct = disabled_correct &&
+	    (uc->uc_stack.ss_flags & SS_DISABLE) == 0;
+	if (signo == SIGUSR1) {
+		// The thread was NOT running on the alternate signal
+		// stack when this signal arrived.
+		level1_correct = (uc->uc_stack.ss_flags & SS_ONSTACK) == 0;
+		raise(SIGUSR2);
+	} else {
+		// The thread WAS running on the alternate signal
+		// stack when this signal arrived.
+		level2_correct = (uc->uc_stack.ss_flags & SS_ONSTACK) != 0;
+	}
+}
+
+ATF_TC(ss_onstack);
+
+ATF_TC_HEAD(ss_onstack, tc)
+{
+
+	atf_tc_set_md_var(tc, "descr", "Test reporting of SS_ONSTACK");
+}
+
+ATF_TC_BODY(ss_onstack, tc)
+{
+	stack_t ss = {
+		.ss_size = SIGSTKSZ,
+	};
+	stack_t oss = {
+		.ss_size = 0,
+	};
+
+	ss.ss_sp = malloc(ss.ss_size);
+	ATF_REQUIRE(ss.ss_sp != NULL);
+	ATF_REQUIRE(sigaltstack(&ss, &oss) == 0);
+
+	// There should be no signal stack currently configured.
+	ATF_CHECK(oss.ss_sp == NULL);
+	ATF_CHECK(oss.ss_size == 0);
+	ATF_CHECK((oss.ss_flags & SS_DISABLE) != 0);
+	ATF_CHECK((oss.ss_flags & SS_ONSTACK) == 0);
+
+	struct sigaction sa = {
+		.sa_sigaction = sig_handler,
+		.sa_flags = SA_ONSTACK | SA_SIGINFO,
+	};
+	ATF_REQUIRE(sigemptyset(&sa.sa_mask) == 0);
+	ATF_REQUIRE(sigaction(SIGUSR1, &sa, NULL) == 0);
+	ATF_REQUIRE(sigaction(SIGUSR2, &sa, NULL) == 0);
+	ATF_REQUIRE(raise(SIGUSR1) == 0);
+
+	ATF_CHECK(level1_correct != -1);
+	ATF_CHECK(level1_correct == 1);
+	ATF_CHECK(level2_correct != -1);
+	ATF_CHECK(level2_correct == 1);
+}
+
+ATF_TP_ADD_TCS(tp)
+{
+
+	ATF_TP_ADD_TC(tp, ss_onstack);
+
+	return (atf_no_error());
+}