From 400cdcd624230f082be3fc322fb5abf8cd553936 Mon Sep 17 00:00:00 2001
From: Yong Cong Sin <ycsin@meta.com>
Date: Thu, 6 Jul 2023 17:05:39 +0800
Subject: [PATCH] posix: signal: implement sigdelset

Implementation and ztest for sigdelset.

Signed-off-by: Yong Cong Sin <ycsin@meta.com>
---
 include/zephyr/posix/signal.h   |  1 +
 lib/posix/signal.c              | 12 +++++
 tests/posix/common/src/signal.c | 86 +++++++++++++++++++++++++++++++++
 3 files changed, 99 insertions(+)

diff --git a/include/zephyr/posix/signal.h b/include/zephyr/posix/signal.h
index 6615fbdae7f40a5..0da478b02e4c685 100644
--- a/include/zephyr/posix/signal.h
+++ b/include/zephyr/posix/signal.h
@@ -62,6 +62,7 @@ typedef struct {
 int sigemptyset(sigset_t *set);
 int sigfillset(sigset_t *set);
 int sigaddset(sigset_t *set, int signo);
+int sigdelset(sigset_t *set, int signo);
 #endif /* CONFIG_POSIX_SIGNAL */
 
 #ifndef SIGEV_NONE
diff --git a/lib/posix/signal.c b/lib/posix/signal.c
index 3aaad5cf046ae59..3507cdce6748de3 100644
--- a/lib/posix/signal.c
+++ b/lib/posix/signal.c
@@ -49,3 +49,15 @@ int sigaddset(sigset_t *set, int signo)
 
 	return 0;
 }
+
+int sigdelset(sigset_t *set, int signo)
+{
+	if (signo_invalid(signo)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	WRITE_BIT(set->sig[signo_word_idx(signo)], signo_word_bit(signo), 0);
+
+	return 0;
+}
diff --git a/tests/posix/common/src/signal.c b/tests/posix/common/src/signal.c
index 043237a105057d1..ade91d2e03f371e 100644
--- a/tests/posix/common/src/signal.c
+++ b/tests/posix/common/src/signal.c
@@ -114,3 +114,89 @@ ZTEST(posix_apis, test_signal_addset)
 			      set.sig[i], sig_mask[i]);
 	}
 }
+
+ZTEST(posix_apis, test_signal_delset_oor)
+{
+	int rc;
+	sigset_t set;
+
+	rc = sigdelset(&set, -1);
+	zassert_equal(rc, -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+
+	rc = sigdelset(&set, 0);
+	zassert_equal(rc, -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+
+	rc = sigdelset(&set, _NSIG + 1);
+	zassert_equal(rc, -1, "rc should be -1");
+	zassert_equal(errno, EINVAL, "errno should be %s", "EINVAL");
+}
+
+#ifdef CONFIG_64BIT
+ZTEST(posix_apis, test_signal_delset_64)
+{
+	sigset_t set;
+	unsigned long sig_mask = -1;
+
+	memset(&set, -1, sizeof(set));
+
+	WRITE_BIT(sig_mask, SIGHUP - 1, 0);
+	zassert_ok(sigdelset(&set, SIGHUP));
+	zassert_equal(set.sig[0], sig_mask, "set.sig[%d of %d] has content: %lx, expected %lx", 0,
+		      ARRAY_SIZE(set.sig), set.sig[0], sig_mask);
+
+	WRITE_BIT(sig_mask, SIGSYS - 1, 0);
+	zassert_ok(sigdelset(&set, SIGSYS));
+	zassert_equal(set.sig[0], sig_mask, "set.sig[%d of %d] has content: %lx, expected %lx", 0,
+		      ARRAY_SIZE(set.sig), set.sig[0], sig_mask);
+
+	WRITE_BIT(sig_mask, SIGRTMIN - 1, 0);
+	zassert_ok(sigdelset(&set, SIGRTMIN));
+	zassert_equal(set.sig[0], sig_mask, "set.sig[%d of %d] has content: %lx, expected %lx", 0,
+		      ARRAY_SIZE(set.sig), set.sig[0], sig_mask);
+
+	WRITE_BIT(sig_mask, SIGRTMIN, 0);
+	zassert_ok(sigdelset(&set, SIGRTMIN + 1));
+	zassert_equal(set.sig[0], sig_mask, "set.sig[%d of %d] has content: %lx, expected %lx", 0,
+		      ARRAY_SIZE(set.sig), set.sig[0], sig_mask);
+
+	WRITE_BIT(sig_mask, SIGRTMAX - 1, 0);
+	zassert_ok(sigdelset(&set, SIGRTMAX));
+	zassert_equal(set.sig[0], sig_mask, "set.sig[%d of %d] has content: %lx, expected %lx", 0,
+		      ARRAY_SIZE(set.sig), set.sig[0], sig_mask);
+}
+#else /* 32BIT */
+ZTEST(posix_apis, test_signal_delset_32)
+{
+	sigset_t set;
+	unsigned long sig_mask[2] = {-1, -1};
+
+	memset(&set, -1, sizeof(set));
+
+	WRITE_BIT(sig_mask[0], SIGHUP - 1, 0);
+	zassert_ok(sigdelset(&set, SIGHUP));
+	zassert_equal(set.sig[0], sig_mask[0], "set.sig[%d of %d] has content: %lx, expected %lx",
+		      0, ARRAY_SIZE(set.sig), set.sig[0], sig_mask[0]);
+
+	WRITE_BIT(sig_mask[0], SIGSYS - 1, 0);
+	zassert_ok(sigdelset(&set, SIGSYS));
+	zassert_equal(set.sig[0], sig_mask[0], "set.sig[%d of %d] has content: %lx, expected %lx",
+		      0, ARRAY_SIZE(set.sig), set.sig[0], sig_mask[0]);
+
+	WRITE_BIT(sig_mask[0], SIGRTMIN - 1, 0);
+	zassert_ok(sigdelset(&set, SIGRTMIN));
+	zassert_equal(set.sig[0], sig_mask[0], "set.sig[%d of %d] has content: %lx, expected %lx",
+		      0, ARRAY_SIZE(set.sig), set.sig[0], sig_mask[0]);
+
+	WRITE_BIT(sig_mask[1], SIGRTMIN % BITS_PER_LONG, 0);
+	zassert_ok(sigdelset(&set, SIGRTMIN + 1));
+	zassert_equal(set.sig[1], sig_mask[1], "set.sig[%d of %d] has content: %lx, expected %lx",
+		      1, ARRAY_SIZE(set.sig), set.sig[1], sig_mask[1]);
+
+	WRITE_BIT(sig_mask[1], (SIGRTMAX - 1) % BITS_PER_LONG, 0);
+	zassert_ok(sigdelset(&set, SIGRTMAX));
+	zassert_equal(set.sig[1], sig_mask[1], "set.sig[%d of %d] has content: %lx, expected %lx",
+		      1, ARRAY_SIZE(set.sig), set.sig[1], sig_mask[1]);
+}
+#endif /* CONFIG_64BIT */