unix: respect MSG_DONTWAIT on sendmsg()

fix bug #18539

Change-Id: Id21362028287d1cbdac469226e6b52f4547a276f
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6796
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>

headers/private/net/net_protocol.h

@@ -108,7 +108,8 @@ struct net_protocol_module_info {
 
 	ssize_t		(*send_data_no_buffer)(net_protocol* self, const iovec* vecs,
 					size_t vecCount, ancillary_data_container* ancillaryData,
-					const struct sockaddr* address, socklen_t addressLength);
+					const struct sockaddr* address, socklen_t addressLength,
+					int flags);
 	ssize_t		(*read_data_no_buffer)(net_protocol* self, const iovec* vecs,
 					size_t vecCount, ancillary_data_container** _ancillaryData,
 					struct sockaddr* _address, socklen_t* _addressLength);

src/add-ons/kernel/network/protocols/unix/UnixDatagramEndpoint.cpp

@@ -210,17 +210,19 @@ UnixDatagramEndpoint::Accept(net_socket** _acceptedSocket)
 ssize_t
 UnixDatagramEndpoint::Send(const iovec* vecs, size_t vecCount,
 	ancillary_data_container* ancillaryData, const struct sockaddr* address,
-	socklen_t addressLength)
+	socklen_t addressLength, int flags)
 {
 	TRACE("[%" B_PRId32 "] %p->UnixDatagramEndpoint::Send()\n",
 		find_thread(NULL), this);
 
-	bigtime_t timeout = absolute_timeout(socket->send.timeout);
+	bigtime_t timeout = 0;
-	if (gStackModule->is_restarted_syscall())
+	if ((flags & MSG_DONTWAIT) == 0) {
-		timeout = gStackModule->restore_syscall_restart_timeout();
+		timeout = absolute_timeout(socket->send.timeout);
-	else
+		if (gStackModule->is_restarted_syscall())
-		gStackModule->store_syscall_restart_timeout(timeout);
+			timeout = gStackModule->restore_syscall_restart_timeout();
-
+		else
+			gStackModule->store_syscall_restart_timeout(timeout);
+	}
 	UnixDatagramEndpointLocker endpointLocker(this);
 
 	if (fShutdownWrite)

src/add-ons/kernel/network/protocols/unix/UnixDatagramEndpoint.h

@@ -35,7 +35,7 @@ public:
 			ssize_t				Send(const iovec* vecs, size_t vecCount,
 									ancillary_data_container* ancillaryData,
 									const struct sockaddr* address,
-									socklen_t addressLength) override;
+									socklen_t addressLength, int flags) override;
 			ssize_t				Receive(const iovec* vecs, size_t vecCount,
 									ancillary_data_container** _ancillaryData,
 									struct sockaddr* _address,

src/add-ons/kernel/network/protocols/unix/UnixEndpoint.h

@@ -56,7 +56,7 @@ public:
 	virtual	ssize_t				Send(const iovec* vecs, size_t vecCount,
 									ancillary_data_container* ancillaryData,
 									const struct sockaddr* address,
-									socklen_t addressLength) = 0;
+									socklen_t addressLength, int flags) = 0;
 	virtual	ssize_t				Receive(const iovec* vecs, size_t vecCount,
 									ancillary_data_container** _ancillaryData,
 									struct sockaddr* _address, socklen_t* _addressLength) = 0;

src/add-ons/kernel/network/protocols/unix/UnixStreamEndpoint.cpp

@@ -374,16 +374,19 @@ UnixStreamEndpoint::Accept(net_socket** _acceptedSocket)
 ssize_t
 UnixStreamEndpoint::Send(const iovec* vecs, size_t vecCount,
 	ancillary_data_container* ancillaryData,
-	const struct sockaddr* address, socklen_t addressLength)
+	const struct sockaddr* address, socklen_t addressLength, int flags)
 {
 	TRACE("[%" B_PRId32 "] %p->UnixStreamEndpoint::Send(%p, %ld, %p)\n",
 		find_thread(NULL), this, vecs, vecCount, ancillaryData);
 
-	bigtime_t timeout = absolute_timeout(socket->send.timeout);
+	bigtime_t timeout = 0;
-	if (gStackModule->is_restarted_syscall())
+	if ((flags & MSG_DONTWAIT) == 0) {
-		timeout = gStackModule->restore_syscall_restart_timeout();
+		timeout = absolute_timeout(socket->send.timeout);
-	else
+		if (gStackModule->is_restarted_syscall())
-		gStackModule->store_syscall_restart_timeout(timeout);
+			timeout = gStackModule->restore_syscall_restart_timeout();
+		else
+			gStackModule->store_syscall_restart_timeout(timeout);
+	}
 
 	UnixStreamEndpointLocker locker(this);
 

src/add-ons/kernel/network/protocols/unix/UnixStreamEndpoint.h

@@ -51,7 +51,7 @@ public:
 			ssize_t				Send(const iovec* vecs, size_t vecCount,
 									ancillary_data_container* ancillaryData,
 									const struct sockaddr* address,
-									socklen_t addressLength) override;
+									socklen_t addressLength, int flags) override;
 			ssize_t				Receive(const iovec* vecs, size_t vecCount,
 									ancillary_data_container** _ancillaryData,
 									struct sockaddr* _address,

src/add-ons/kernel/network/protocols/unix/unix.cpp

@@ -408,10 +408,10 @@ unix_process_ancillary_data(net_protocol *self,
 ssize_t
 unix_send_data_no_buffer(net_protocol *_protocol, const iovec *vecs,
 	size_t vecCount, ancillary_data_container *ancillaryData,
-	const struct sockaddr *address, socklen_t addressLength)
+	const struct sockaddr *address, socklen_t addressLength, int flags)
 {
 	return ((UnixEndpoint*)_protocol)->Send(vecs, vecCount, ancillaryData,
-		address, addressLength);
+		address, addressLength, flags);
 }
 
 

src/add-ons/kernel/network/stack/net_socket.cpp

@@ -1393,7 +1393,7 @@ socket_send(net_socket* socket, msghdr* header, const void* data, size_t length,
 
 		ssize_t written = socket->first_info->send_data_no_buffer(
 			socket->first_protocol, vecs, vecCount, ancillaryData, address,
-			addressLength);
+			addressLength, flags);
 		if (written > 0)
 			ancillaryDataDeleter.Detach();
 		return written;

src/tests/system/network/Jamfile

@@ -19,6 +19,8 @@ SimpleTest if_nameindex : if_nameindex.c : $(TARGET_NETWORK_LIBS) ;
 
 SimpleTest unix_dgram_test : unix_dgram_test.cpp : $(TARGET_NETWORK_LIBS) ;
 
+SimpleTest unix_send_test : unix_send_test.c : $(TARGET_NETWORK_LIBS) ;
+
 SimpleTest tcp_connection_test : tcp_connection_test.cpp
 	: $(TARGET_NETWORK_LIBS) ;
 

src/tests/system/network/unix_send_test.c

@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <stdbool.h>
+
+int main() {
+	int fds[2];
+	int domain;
+	domain = AF_UNIX;
+ // domain = AF_INET;
+	printf("Domain: %i\n", domain);
+	int ret = socketpair(domain, SOCK_DGRAM, 0, fds); // try also: SOCK_STREAM
+	if(ret) {
+		perror("Could not get socketpair");
+		return 1;
+	}
+
+	struct timeval v = {
+		.tv_sec = 1,
+		.tv_usec = 0
+	};
+
+	// uncomment to allow send to timeout with ETIMEDOUT after 1 second
+	//ret = setsockopt(fds[0], SOL_SOCKET, SO_SNDTIMEO, &v, sizeof(v));
+	if(ret) {
+		perror("setsockopt");
+	}
+
+	size_t bufLen = 1024;
+	char *buf = calloc(bufLen, 1);
+	int ok = 0;
+	while(true) {
+		printf("send %i\n", ok);
+		ret = send(fds[0], &buf[0], bufLen, MSG_DONTWAIT);
+		// eventually: EAGAIN (on Linux and Haiku), ENOBUFS (on macOS)
+		if(ret < 0) {
+			perror("send");
+			break;
+		} else {
+			ok++;
+		}
+	}
+
+	return 0;
+}