lib: posix: move eventfd to subsys/net

include/zephyr/net/socket.h

@@ -39,6 +39,8 @@ struct zsock_pollfd {
 	short revents;
 };
 
+typedef uint64_t zsock_eventfd_t;
+
 /* ZSOCK_POLL* values are compatible with Linux */
 /** zsock_poll: Poll for readability */
 #define ZSOCK_POLLIN 1
@@ -75,6 +77,12 @@ struct zsock_pollfd {
 /** zsock_shutdown: Shut down for both reading and writing */
 #define ZSOCK_SHUT_RDWR 2
 
+/** zsock_eventfd **/
+#define ZSOCK_EFD_IN_USE    0x1
+#define ZSOCK_EFD_SEMAPHORE 0x2
+#define ZSOCK_EFD_NONBLOCK  O_NONBLOCK
+#define ZSOCK_EFD_FLAGS_SET (ZSOCK_EFD_SEMAPHORE | ZSOCK_EFD_NONBLOCK)
+
 /** Protocol level for TLS.
  *  Here, the same socket protocol level for TLS as in Linux was used.
  */
@@ -268,6 +276,43 @@ __syscall int zsock_socket(int family, int type, int proto);
  */
 __syscall int zsock_socketpair(int family, int type, int proto, int *sv);
 
+/**
+ * @brief Create an unnamed pair of connected sockets
+ *
+ * @details
+ * @rst
+ * See `POSIX.1-2017 article
+ * <https://man7.org/linux/man-pages/man2/eventfd.2.html>`__
+ * for normative description.
+ * This function is also exposed as ``eventfd()``
+ * if :kconfig:option:`CONFIG_NET_SOCKETS_POSIX_NAMES` is defined.
+ * @endrst
+ */
+__syscall int zsock_eventfd(unsigned int initval, int flags);
+
+/**
+ * @brief Read from an eventfd
+ *
+ * If call is successful, the value parameter will have the value 1
+ *
+ * @param fd File descriptor
+ * @param value Pointer for storing the read value
+ *
+ * @return 0 on success, -1 on error
+ */
+__syscall int zsock_eventfd_read(int fd, zsock_eventfd_t *value);
+
+/**
+ * @brief Write to an eventfd
+ *
+ * @param fd File descriptor
+ * @param value Value to write
+ *
+ * @return 0 on success, -1 on error
+ */
+__syscall int zsock_eventfd_write(int fd, zsock_eventfd_t value);
+
+
 /**
  * @brief Close a network socket
  *
@@ -685,6 +730,8 @@ int zsock_getnameinfo(const struct sockaddr *addr, socklen_t addrlen,
 
 #define pollfd zsock_pollfd
 
+#define eventfd_t zsock_eventfd_t
+
 /** POSIX wrapper for @ref zsock_socket */
 static inline int socket(int family, int type, int proto)
 {
@@ -697,6 +744,24 @@ static inline int socketpair(int family, int type, int proto, int sv[2])
 	return zsock_socketpair(family, type, proto, sv);
 }
 
+/** POSIX wrapper for @ref zsock_eventfd */
+static inline int eventfd(unsigned int initval, int flags)
+{
+	return zsock_eventfd(initval, flags);
+}
+
+/** POSIX wrapper for @ref zsock_eventfd_read */
+static inline int eventfd_read(int fd, zsock_eventfd_t *value)
+{
+	return zsock_eventfd_read(fd, value);
+}
+
+/** POSIX wrapper for @ref zsock_eventfd_write */
+static inline int eventfd_write(int fd, zsock_eventfd_t value)
+{
+	return zsock_eventfd_write(fd, value);
+}
+
 /** POSIX wrapper for @ref zsock_close */
 static inline int close(int sock)
 {
@@ -896,6 +961,15 @@ static inline char *inet_ntop(sa_family_t family, const void *src, char *dst,
 /** POSIX wrapper for @ref ZSOCK_SHUT_RDWR */
 #define SHUT_RDWR ZSOCK_SHUT_RDWR
 
+/** POSIX wrapper for @ref ZSOCK_EFD_IN_USE */
+#define EFD_IN_USE ZSOCK_EFD_IN_USE
+/** POSIX wrapper for @ref ZSOCK_EFD_SEMAPHORE */
+#define EFD_SEMAPHORE ZSOCK_EFD_SEMAPHORE
+/** POSIX wrapper for @ref ZSOCK_EFD_NONBLOCK */
+#define EFD_NONBLOCK ZSOCK_EFD_NONBLOCK
+/** POSIX wrapper for @ref ZSOCK_EFD_FLAGS_SET */
+#define EFD_FLAGS_SET ZSOCK_EFD_FLAGS_SET
+
 /** POSIX wrapper for @ref DNS_EAI_BADFLAGS */
 #define EAI_BADFLAGS DNS_EAI_BADFLAGS
 /** POSIX wrapper for @ref DNS_EAI_NONAME */

lib/posix/CMakeLists.txt

@@ -23,7 +23,6 @@ zephyr_library_sources_ifdef(CONFIG_PTHREAD_IPC semaphore.c)
 zephyr_library_sources_ifdef(CONFIG_PTHREAD_IPC pthread_key.c)
 zephyr_library_sources_ifdef(CONFIG_POSIX_MQUEUE mqueue.c)
 zephyr_library_sources_ifdef(CONFIG_POSIX_FS fs.c)
-zephyr_library_sources_ifdef(CONFIG_EVENTFD eventfd.c)
 add_subdirectory_ifdef(CONFIG_GETOPT getopt)
 
 if(NOT (CONFIG_BOARD_NATIVE_POSIX OR CONFIG_BOARD_NATIVE_POSIX_64BIT))

lib/posix/Kconfig

@@ -110,19 +110,3 @@ config APP_LINK_WITH_POSIX_SUBSYS
 	depends on POSIX_API
 	help
 	  Add POSIX subsystem header files to the 'app' include path.
-
-config EVENTFD
-	bool "Support for eventfd"
-	depends on !ARCH_POSIX
-	help
-	  Enable support for event file descriptors, eventfd. An eventfd can
-	  be used as an event wait/notify mechanism together with POSIX calls
-	  like read, write and poll.
-
-config EVENTFD_MAX
-	int "Maximum number of eventfd's"
-	depends on EVENTFD
-	default 1
-	range 1 4096
-	help
-	  The maximum number of supported event file descriptors.

samples/net/sockets/eventfd/prj.conf

@@ -0,0 +1,11 @@
+# General config
+CONFIG_NEWLIB_LIBC=y
+CONFIG_NEWLIB_LIBC_NANO=n
+
+# eventfd() implementation only makes sense for networking APIs.
+CONFIG_NETWORKING=y
+CONFIG_NET_SOCKETS=y
+CONFIG_NET_SOCKETS_POSIX_NAMES=y
+CONFIG_NET_EVENTFD=y
+CONFIG_NET_SLIP_TAP=n
+CONFIG_TEST_RANDOM_GENERATOR=y

samples/posix/eventfd/src/main.c → samples/net/sockets/eventfd/src/main.c

@@ -6,11 +6,10 @@
  * This sample application is roughly based on the sample code in Linux
  * manpage for eventfd().
  */
-#include <sys/eventfd.h>
-#include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <stdint.h>
+#include <net/socket.h>
 
 #define fatal(msg) \
 	do { perror(msg); exit(EXIT_FAILURE); } while (0)
@@ -31,8 +30,8 @@ void writer(void)
 	for (j = 1; j < g_argc; j++) {
 		printf("Writing %s to efd\n", g_argv[j]);
 		u = strtoull(g_argv[j], NULL, 0);
-		s = write(efd, &u, sizeof(uint64_t));
-		if (s != sizeof(uint64_t)) {
+		s = eventfd_write(efd, u);
+		if (s != 0) {
 			fatal("write");
 		}
 	}
@@ -44,21 +43,21 @@ void reader(void)
 	uint64_t u;
 	ssize_t s;
 
-	sleep(1);
+	k_sleep(K_MSEC(1000));
 
 	printf("About to read\n");
-	s = read(efd, &u, sizeof(uint64_t));
-	if (s != sizeof(uint64_t)) {
+	s = eventfd_read(efd, &u);
+	if (s != 0) {
 		fatal("read");
 	}
 	printf("Read %llu (0x%llx) from efd\n",
 	       (unsigned long long)u, (unsigned long long)u);
 }
 
-int main(int argc, char *argv[])
+void main(void)
 {
-	argv = input_argv;
-	argc = sizeof(input_argv) / sizeof(input_argv[0]);
+	char **argv = input_argv;
+	int argc = sizeof(input_argv) / sizeof(input_argv[0]);
 
 	if (argc < 2) {
 		fprintf(stderr, "Usage: %s <num>...\n", argv[0]);
@@ -77,6 +76,4 @@ int main(int argc, char *argv[])
 	reader();
 
 	printf("Finished\n");
-
-	return 0;
 }

subsys/net/lib/sockets/CMakeLists.txt

@@ -31,5 +31,6 @@ if(CONFIG_SOCKS)
 endif()
 
 zephyr_sources_ifdef(CONFIG_NET_SOCKETPAIR socketpair.c)
+zephyr_sources_ifdef(CONFIG_NET_EVENTFD eventfd.c)
 
 zephyr_link_libraries_ifdef(CONFIG_MBEDTLS mbedTLS)

subsys/net/lib/sockets/Kconfig

@@ -257,6 +257,21 @@ config NET_SOCKETPAIR_BUFFER_SIZE
 	help
 	  Buffer size for socketpair(2)
 
+config NET_EVENTFD
+	bool "Support for eventfd"
+	help
+	  Enable support for event file descriptors, eventfd. An eventfd can
+	  be used as an event wait/notify mechanism together with POSIX calls
+	  like read, write and poll.
+
+config NET_EVENTFD_MAX
+	int "Maximum number of eventfd's"
+	depends on NET_EVENTFD
+	default 1
+	range 1 4096
+	help
+	  The maximum number of supported event file descriptors.
+
 config NET_SOCKETS_NET_MGMT
 	bool "Network management socket support [EXPERIMENTAL]"
 	depends on NET_MGMT_EVENT