syscalls: shutdown

kernel-src/arch/x86-64/syscall.asm

@@ -91,6 +91,7 @@ extern syscall_sigsuspend
 extern syscall_sigtimedwait
 extern syscall_sigpending
 extern syscall_killthread
+extern syscall_shutdown
 syscalltab:
 dq syscall_print
 dq syscall_mmap
@@ -184,7 +185,8 @@ dq syscall_sigsuspend
 dq syscall_sigtimedwait
 dq syscall_sigpending
 dq syscall_killthread
-syscallcount equ 92
+dq syscall_shutdown
+syscallcount equ 93
 section .text
 global arch_syscall_entry
 ; on entry:

kernel-src/arch/x86-64/syscalllog.c

@@ -5,7 +5,7 @@
 
 #ifdef SYSCALL_LOGGING
 
-#define SYSCALL_COUNT 92
+#define SYSCALL_COUNT 93
 #define LOGSTR(x) arch_e9_puts(x)
 
 static char *name[] = {
@@ -100,7 +100,8 @@ static char *name[] = {
 	"sigsuspend",
 	"sigtimedwait",
 	"sigpending",
-	"killthread"
+	"killthread",
+	"shutdown"
 };
 
 static char *args[] = {
@@ -195,7 +196,8 @@ static char *args[] = {
 	"sigset %p", // sigsuspend
 	"sigset %p info %p, timespec %p", // sigtimedwait
 	"sigset %p\n", // sigpending
-	"pid %d tid %d signal %d" // killthread
+	"pid %d tid %d signal %d", // killthread
+	"how %d" // shutdown
 };
 
 #endif

kernel-src/include/kernel/sock.h

@@ -13,6 +13,10 @@
 #define SOCKET_STATE_CONNECTED 2
 #define SOCKET_STATE_LISTENING 3
 
+#define SOCKET_SHUTDOWN_READ 1
+#define SOCKET_SHUTDOWN_WRITE 2
+#define SOCKET_SHUTDOWN_RW 3
+
 typedef struct {
 	struct socketops_t *ops;
 	mutex_t mutex;
@@ -21,6 +25,7 @@ typedef struct {
 	netdev_t *netdev;
 	pollheader_t pollheader;
 	int type;
+	int shutdown;
 } socket_t;
 
 typedef struct {
@@ -67,6 +72,7 @@ typedef struct socketops_t {
 	size_t (*datacount)(socket_t *socket);
 	void (*destroy)(socket_t *socket);
 	int (*setopt)(socket_t *socket, int optname, void *buffer, size_t len, cred_t *cred);
+	int (*shutdown)(socket_t *socket, int how);
 } socketops_t;
 
 typedef struct {

kernel-src/io/net/localsocket.c

@@ -13,7 +13,7 @@
 struct localpair_t;
 struct binding_t;
 typedef struct {
-	socket_t socket;
+	socket_t socket; // shutdown state is shared with pair
 	ringbuffer_t ringbuffer; // shared with pair
 	// client/connected server
 	struct localpair_t *pair;
@@ -1003,6 +1003,47 @@ static int localsock_getpeername(socket_t *socket, sockaddr_t *addr) {
 	return 0;
 }
 
+static int localsock_shutdown(socket_t *socket, int how) {
+	localsocket_t *localsocket = (localsocket_t *)socket;
+	MUTEX_ACQUIRE(&socket->mutex);
+	int error;
+
+	localpair_t *pair = localsocket->pair;
+	// socket not connected
+	if (pair == NULL) {
+		error = ENOTCONN;
+		goto leave;
+	}
+
+	MUTEX_ACQUIRE(&pair->mutex);
+
+	localsocket_t *peer = localsocket->pair->client == localsocket ? localsocket->pair->server : localsocket->pair->client;
+
+	socket->shutdown |= how;
+
+	int poll_events = 0;
+
+	// XXX is this the correct behaviour?
+	if (how & SOCKET_SHUTDOWN_READ)
+		poll_events |= POLLHUP;
+
+	if (how & SOCKET_SHUTDOWN_WRITE)
+		poll_events |= POLLIN;
+
+	if (peer)
+		poll_event(&peer->socket.pollheader, poll_events);
+
+	error = 0;
+
+	leave:
+	if (pair)
+		MUTEX_RELEASE(&pair->mutex);
+
+	MUTEX_RELEASE(&socket->mutex);
+	return error;
+
+}
+
 static socketops_t socketops = {
 	.bind = localsock_bind,
 	.listen = localsock_listen,
@@ -1014,7 +1055,8 @@ static socketops_t socketops = {
 	.poll = localsock_poll,
 	.datacount = localsocket_datacount,
 	.getname = localsock_getname,
-	.getpeername = localsock_getpeername
+	.getpeername = localsock_getpeername,
+	.shutdown = localsock_shutdown
 };
 
 socket_t *localsock_createsocket() {

kernel-src/io/net/tcp.c

@@ -1832,6 +1832,11 @@ static int tcp_setopt(socket_t *socket, int optname, void *buffer, size_t len, c
 	return 0;
 }
 
+static int tcp_shutdown(socket_t *socket, int how) {
+	printf("tcp: shutdown is not implemented\n");
+	return ENOSYS;
+}
+
 static socketops_t socketops = {
 	.bind = tcp_bind,
 	.send = tcp_send,
@@ -1844,7 +1849,8 @@ static socketops_t socketops = {
 	.destroy = tcp_destroy,
 	.getname = tcp_getname,
 	.getpeername = tcp_getpeername,
-	.setopt = tcp_setopt
+	.setopt = tcp_setopt,
+	.shutdown = tcp_shutdown
 };
 
 socket_t *tcp_createsocket() {

kernel-src/io/net/udp.c

@@ -109,7 +109,7 @@ void udp_process(netdev_t *netdev, void *buffer, uint32_t peer) {
 
 	spinlock_release(&portlock);
 
-	if (socket == NULL) // drop packet if no socket listening on port
+	if (socket == NULL || (socket->socket.shutdown & SOCKET_SHUTDOWN_READ)) // drop packet if no socket listening on port or its not accepting incoming data
 		return;
 
 	dataheader_t header = {
@@ -185,7 +185,14 @@ static int udp_send(socket_t *socket, sockdesc_t *sockdesc) {
 	int e;
 	MUTEX_ACQUIRE(&socket->mutex);
 
-	if (sockdesc->addr == NULL && socket->state != SOCKET_STATE_CONNECTED) {
+	if (socket->shutdown & SOCKET_SHUTDOWN_WRITE) {
+		// XXX should SIGPIPE be sent in this case?
+		e = 0;
+		sockdesc->donecount = 0;
+		return 0;
+	}
+
+	if (sockdesc->addr == NULL) {
 		e = ENOTCONN;
 		goto cleanup;
 	}
@@ -337,6 +344,18 @@ static int udp_poll(socket_t *socket, polldata_t *data, int events) {
 	return revents;
 }
 
+static int udp_shutdown(socket_t *socket, int how) {
+	if (how > SOCKET_SHUTDOWN_RW)
+		return EINVAL;
+
+	MUTEX_ACQUIRE(&socket->mutex);
+
+	socket->shutdown |= how;
+
+	MUTEX_RELEASE(&socket->mutex);
+	return 0;
+}
+
 static socketops_t socketops = {
 	.bind = udp_bind,
 	.send = udp_send,
@@ -344,7 +363,8 @@ static socketops_t socketops = {
 	.destroy = udp_destroy,
 	.poll = udp_poll,
 	.getname = udp_getname,
-	.getpeername = udp_getpeername
+	.getpeername = udp_getpeername,
+	.shutdown = udp_shutdown
 };
 
 socket_t *udp_createsocket() {