Add a test for forked processes inheriting their parent's signal stack.

ok guenther@

1 files changed, 67 insertions, 0 deletions

diff --git a/regress/sys/kern/signal/sigaltstack_fork/sigaltstack_fork.c b/regress/sys/kern/signal/sigaltstack_fork/sigaltstack_fork.c
new file mode 100644
index 00000000000..8b6237bdf9b
--- /dev/null
+++ b/regress/sys/kern/signal/sigaltstack_fork/sigaltstack_fork.c
@@ -0,0 +1,67 @@
+/*	$OpenBSD: sigaltstack_fork.c,v 1.1 2011/11/22 23:06:49 joshe Exp $	*/
+
+/*
+ * Public domain.  2011, Joshua Elsasser
+ *
+ * Test if child processes inherit an alternate signal stack.
+ */
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <err.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+void
+check_stack(void *buf, const char *label)
+{
+	struct sigaltstack ss;
+
+	bzero(&ss, sizeof(ss));
+	if (sigaltstack(NULL, &ss) != 0)
+		err(1, "failed to get sigaltstack in parent");
+	if (ss.ss_sp != buf ||
+	    ss.ss_size != SIGSTKSZ ||
+	    ss.ss_flags != 0)
+		errx(1, "bad sigaltstack value in %s: "
+		    "buf=%p ss_sp=%p ss_size=%zu ss_flags=0x%x",
+		    label, buf, ss.ss_sp, ss.ss_size, ss.ss_flags);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct sigaltstack ss;
+	int status;
+	pid_t kid;
+	void *buf;
+
+	if ((buf = malloc(SIGSTKSZ)) == NULL)
+		err(1, "malloc failed");
+
+	bzero(&ss, sizeof(ss));
+	ss.ss_sp = buf;
+	ss.ss_size = SIGSTKSZ;
+	if (sigaltstack(&ss, NULL) != 0)
+		err(1, "failed to set sigaltstack");
+
+	check_stack(buf, "parent");
+
+	if ((kid = fork()) == -1)
+		err(1, "fork failed");
+
+	if (kid == 0) {
+		check_stack(buf, "child");
+		_exit(0);
+	}
+
+	if (waitpid(kid, &status, 0) != kid)
+		err(1, "waitpid failed");
+	if (!WIFEXITED(status))
+		errx(1, "child did not exit normally");
+
+	return (WEXITSTATUS(status));
+}