[RFC] posix: signal: empty + fill + set

include/zephyr/posix/signal.h

@@ -12,6 +12,62 @@
 extern "C" {
 #endif
 
+#ifdef CONFIG_POSIX_SIGNAL
+enum {
+	SIGABRT = 1,
+	SIGALRM,
+	SIGBUS,
+	SIGCHLD,
+	SIGCONT,
+	SIGFPE,
+	SIGHUP,
+	SIGILL,
+	SIGINT,
+	SIGKILL,
+	SIGPIPE,
+	SIGQUIT,
+	SIGSEGV,
+	SIGSTOP,
+	SIGTERM,
+	SIGTSTP,
+	SIGTTIN,
+	SIGTTOU,
+	SIGUSR1,
+	SIGUSR2,
+	SIGPOLL,
+	SIGPROF,
+	SIGSYS,
+	SIGTRAP,
+	SIGURG,
+	SIGVTALRM,
+	SIGXCPU,
+	SIGXFSZ,
+};
+
+/* Signal set management definitions and macros. */
+#define MIN_SIGNO       1                       /* Lowest valid signal number */
+#define MAX_SIGNO       CONFIG_POSIX_SIGNAL_MAX /* Highest valid signal number */
+
+/* Definitions for "standard" signals */
+#define SIGSTDMIN       1                           /* First standard signal number */
+#define SIGSTDMAX       CONFIG_POSIX_SIGNAL_STD_MAX /* Last standard signal number */
+
+/* Definitions for "real time" signals */
+#define SIGRTMIN        (SIGSTDMAX + 1) /* First real time signal */
+#define SIGRTMAX        MAX_SIGNO       /* Last real time signal */
+#define _NSIG           (MAX_SIGNO + 1) /* Biggest signal number + 1 */
+#define NSIG            _NSIG           /* _NSIG variant commonly used */
+
+/* sigset_t is represented as an array of 32-b unsigned integers.
+ * _SIGSET_NELEM is the allocated size of the array
+ */
+#define _SIGSET_NELEM   ((_NSIG + 31) >> 5)
+
+#define _SIGSET_NDX(s)  ((s) >> 5)    /* Get array index from signal number */
+#define _SIGSET_BIT(s)  ((s) & 0x1f)  /* Get bit number from signal number */
+#define _SIGNO2SET(s)   ((uint32_t)1 << _SIGSET_BIT(s))
+#endif /* CONFIG_POSIX_SIGNAL */
+
 #ifndef SIGEV_NONE
 #define SIGEV_NONE 1
 #endif
@@ -41,6 +97,16 @@ typedef struct sigevent {
 	#endif
 } sigevent;
 
+#ifdef CONFIG_POSIX_SIGNAL
+typedef struct sigset {
+	uint32_t _elem[_SIGSET_NELEM];
+} sigset_t;
+
+int sigaddset(sigset_t *set, int signo);
+int sigemptyset(sigset_t *set);
+int sigfillset(sigset_t *set);
+#endif /* CONFIG_POSIX_SIGNAL */
+
 #ifdef __cplusplus
 }
 #endif

lib/posix/CMakeLists.txt

@@ -38,6 +38,7 @@ zephyr_library_sources_ifdef(CONFIG_POSIX_FS fs.c)
 zephyr_library_sources_ifdef(CONFIG_EVENTFD eventfd.c)
 zephyr_library_sources_ifdef(CONFIG_FNMATCH fnmatch.c)
 add_subdirectory_ifdef(CONFIG_GETOPT getopt)
+add_subdirectory_ifdef(CONFIG_POSIX_SIGNAL signal)
 
 zephyr_library_include_directories(
   ${ZEPHYR_BASE}/kernel/include

lib/posix/Kconfig

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
 source "lib/posix/getopt/Kconfig"
+source "lib/posix/signal/Kconfig"
 
 config POSIX_MAX_FDS
 	int "Maximum number of open file descriptors"

lib/posix/signal/CMakeLists.txt

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_library_sources(
+  addset.c
+  emptyset.c
+  fillset.c
+)

lib/posix/signal/Kconfig

@@ -0,0 +1,23 @@
+# Copyright (c) 2023 Meta
+# SPDX-License-Identifier: Apache-2.0
+
+
+menuconfig POSIX_SIGNAL
+	bool "POSIX signal support"
+	default y if POSIX_API
+	help
+	  This option adds support of POSIX signal.
+
+config POSIX_SIGNAL_MAX
+	int "Highest valid signal number"
+	depends on POSIX_SIGNAL
+	default 63
+	help
+	  Defines the highest valid signal number.
+
+config POSIX_SIGNAL_STD_MAX
+	int "Highest number for standard signal"
+	depends on POSIX_SIGNAL
+	default 31
+	help
+	  Defines the highest number for standard signal.

lib/posix/signal/addset.c

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <signal.h>
+#include <errno.h>
+
+int sigaddset(sigset_t *set, int signo)
+{
+	if ((set == NULL) || (signo <= 0) || (signo >= NSIG)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	set->_elem[_SIGSET_NDX(signo)] |= _SIGNO2SET(signo);
+
+	return 0;
+}

lib/posix/signal/emptyset.c

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <signal.h>
+
+int sigemptyset(sigset_t *set)
+{
+	for (int ndx = 0; ndx < _SIGSET_NELEM; ndx++) {
+		set->_elem[ndx] = 0;
+	}
+
+	return 0;
+}

lib/posix/signal/fillset.c

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <signal.h>
+#include <stdint.h>
+
+int sigfillset(sigset_t *set)
+{
+	for (int ndx = 0; ndx < _SIGSET_NELEM; ndx++) {
+		set->_elem[ndx] = UINT32_MAX;
+	}
+
+	return 0;
+}

tests/posix/signal/CMakeLists.txt

@@ -0,0 +1,10 @@
+# Copyright (c) 2023, Meta
+#
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(signal)
+
+FILE(GLOB app_sources src/*.c)
+target_sources(app PRIVATE ${app_sources})

tests/posix/signal/Kconfig

@@ -0,0 +1,5 @@
+# Copyright (c) 2023, Meta
+#
+# SPDX-License-Identifier: Apache-2.0
+
+source "Kconfig.zephyr"

tests/posix/signal/prj.conf

@@ -0,0 +1,3 @@
+CONFIG_ZTEST=y
+CONFIG_ZTEST_NEW_API=y
+CONFIG_POSIX_API=y

tests/posix/signal/src/addset.c

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <signal.h>
+#include <errno.h>
+
+#include <zephyr/ztest.h>
+#include <zephyr/sys/util.h>
+#include <zephyr/sys/util_macro.h>
+
+ZTEST(posix_signal_apis, test_posix_signal_addset)
+{
+	sigset_t set;
+	int signo;
+	int rc;
+
+	for (int i = 0; i < ARRAY_SIZE(set._elem); i++) {
+		set._elem[i] = 0u;
+	}
+
+	signo = 21;
+	zassert_ok(sigaddset(&set, signo));
+	zassert_equal(set._elem[signo >> 5], BIT(signo), "Signal %d is not set", signo);
+
+	signo = 42;
+	zassert_ok(sigaddset(&set, signo));
+	zassert_equal(set._elem[21 >> 5], BIT(21), "Signal %d is not set", 21);
+	zassert_equal(set._elem[signo >> 5], BIT(signo % (8 * sizeof(set._elem[0]))),
+		      "Signal %d is not set", signo);
+
+	rc = sigaddset(&set, 0);
+	zassert_equal(rc, -1, "rc should be -1, not %d", rc);
+	zassert_equal(errno, EINVAL, "errno should be EINVAL, not %d", errno);
+
+	rc = sigaddset(&set, NSIG);
+	zassert_equal(rc, -1, "rc should be -1, not %d", rc);
+	zassert_equal(errno, EINVAL, "errno should be EINVAL, not %d", errno);
+}

tests/posix/signal/src/emptyset.c

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+#include <zephyr/sys/util.h>
+
+#include <signal.h>
+
+ZTEST(posix_signal_apis, test_posix_signal_emptyset)
+{
+	sigset_t set;
+
+	for (int i = 0; i < ARRAY_SIZE(set._elem); i++) {
+		set._elem[i] = 0xffffffffu;
+	}
+
+	zassert_ok(sigemptyset(&set));
+
+	for (int i = 0; i < ARRAY_SIZE(set._elem); i++) {
+		zassert_equal(set._elem[i], 0, "signal is not empty");
+	}
+}

tests/posix/signal/src/fillset.c

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2023 Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+#include <zephyr/sys/util.h>
+#include <stdint.h>
+
+#include <signal.h>
+
+ZTEST(posix_signal_apis, test_posix_signal_fillset)
+{
+	sigset_t set;
+
+	for (int i = 0; i < ARRAY_SIZE(set._elem); i++) {
+		set._elem[i] = 0u;
+	}
+
+	zassert_ok(sigfillset(&set));
+
+	for (int i = 0; i < ARRAY_SIZE(set._elem); i++) {
+		zassert_equal(set._elem[i], UINT32_MAX, "signal is not filled");
+	}
+}

tests/posix/signal/src/main.c

@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2023, Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <zephyr/ztest.h>
+
+ZTEST_SUITE(posix_signal_apis, NULL, NULL, NULL, NULL, NULL);