Add a small test to prevent regressions.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 tests/tcg/multiarch/sigreturn-sigmask.c | 51 +++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 tests/tcg/multiarch/sigreturn-sigmask.c

diff --git a/tests/tcg/multiarch/sigreturn-sigmask.c b/tests/tcg/multiarch/sigreturn-sigmask.c
new file mode 100644
index 00000000000..e6cc904898d
--- /dev/null
+++ b/tests/tcg/multiarch/sigreturn-sigmask.c
@@ -0,0 +1,51 @@
+/*
+ * Test that sigreturn() does not corrupt the signal mask.
+ * Block SIGUSR2 and handle SIGUSR1.
+ * Then sigwait() SIGUSR2, which relies on it remaining blocked.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+int seen_sig = -1;
+
+static void signal_func(int sig)
+{
+    seen_sig = sig;
+}
+
+static void *thread_func(void *arg)
+{
+    kill(getpid(), SIGUSR2);
+    return NULL;
+}
+
+int main(void)
+{
+    struct sigaction act = {
+        .sa_handler = signal_func,
+    };
+    pthread_t thread;
+    sigset_t set;
+    int sig;
+
+    assert(sigaction(SIGUSR1, &act, NULL) == 0);
+
+    assert(sigemptyset(&set) == 0);
+    assert(sigaddset(&set, SIGUSR2) == 0);
+    assert(sigprocmask(SIG_BLOCK, &set, NULL) == 0);
+
+    kill(getpid(), SIGUSR1);
+    assert(seen_sig == SIGUSR1);
+
+    assert(pthread_create(&thread, NULL, thread_func, NULL) == 0);
+    assert(sigwait(&set, &sig) == 0);
+    assert(sig == SIGUSR2);
+    assert(pthread_join(thread, NULL) == 0);
+
+    return EXIT_SUCCESS;
+}
-- 
2.47.0

On 10/17/24 05:54, Ilya Leoshkevich wrote:
> Add a small test to prevent regressions.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/multiarch/sigreturn-sigmask.c | 51 +++++++++++++++++++++++++
>   1 file changed, 51 insertions(+)
>   create mode 100644 tests/tcg/multiarch/sigreturn-sigmask.c

This needs -lpthread.  I'll fix while applying.


r~

On 10/17/24 05:54, Ilya Leoshkevich wrote:
> Add a small test to prevent regressions.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   tests/tcg/multiarch/sigreturn-sigmask.c | 51 +++++++++++++++++++++++++
>   1 file changed, 51 insertions(+)
>   create mode 100644 tests/tcg/multiarch/sigreturn-sigmask.c


Acked-by: Richard Henderson <richard.henderson@linaro.org>

r~

> 
> diff --git a/tests/tcg/multiarch/sigreturn-sigmask.c b/tests/tcg/multiarch/sigreturn-sigmask.c
> new file mode 100644
> index 00000000000..e6cc904898d
> --- /dev/null
> +++ b/tests/tcg/multiarch/sigreturn-sigmask.c
> @@ -0,0 +1,51 @@
> +/*
> + * Test that sigreturn() does not corrupt the signal mask.
> + * Block SIGUSR2 and handle SIGUSR1.
> + * Then sigwait() SIGUSR2, which relies on it remaining blocked.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + */
> +#include <assert.h>
> +#include <pthread.h>
> +#include <signal.h>
> +#include <stdlib.h>
> +#include <unistd.h>
> +
> +int seen_sig = -1;
> +
> +static void signal_func(int sig)
> +{
> +    seen_sig = sig;
> +}
> +
> +static void *thread_func(void *arg)
> +{
> +    kill(getpid(), SIGUSR2);
> +    return NULL;
> +}
> +
> +int main(void)
> +{
> +    struct sigaction act = {
> +        .sa_handler = signal_func,
> +    };
> +    pthread_t thread;
> +    sigset_t set;
> +    int sig;
> +
> +    assert(sigaction(SIGUSR1, &act, NULL) == 0);
> +
> +    assert(sigemptyset(&set) == 0);
> +    assert(sigaddset(&set, SIGUSR2) == 0);
> +    assert(sigprocmask(SIG_BLOCK, &set, NULL) == 0);
> +
> +    kill(getpid(), SIGUSR1);
> +    assert(seen_sig == SIGUSR1);
> +
> +    assert(pthread_create(&thread, NULL, thread_func, NULL) == 0);
> +    assert(sigwait(&set, &sig) == 0);
> +    assert(sig == SIGUSR2);
> +    assert(pthread_join(thread, NULL) == 0);
> +
> +    return EXIT_SUCCESS;
> +}