Add recvmsg(2) and sendmsg(2).

kernel/include/sortix/syscallnum.h

@@ -163,6 +163,8 @@
 #define SYSCALL_SIGPENDING 135
 #define SYSCALL_SIGPROCMASK 136
 #define SYSCALL_SIGSUSPEND 137
-#define SYSCALL_MAX_NUM 138 /* index of highest constant + 1 */
+#define SYSCALL_SENDMSG 138
+#define SYSCALL_RECVMSG 139
+#define SYSCALL_MAX_NUM 140 /* index of highest constant + 1 */
 
 #endif

kernel/io.cpp

@@ -22,6 +22,7 @@
 
 *******************************************************************************/
 
+#include <sys/socket.h>
 #include <sys/types.h>
 
 #include <assert.h>
@@ -968,6 +969,47 @@ static int sys_mkpartition(int fd, off_t start, off_t length, int flags)
 	return CurrentProcess()->GetDTable()->Allocate(partition_desc, fdflags);
 }
 
+static ssize_t sys_sendmsg(int fd, const struct msghdr* user_msg, int flags)
+{
+	struct msghdr msg;
+	if ( !CopyFromUser(&msg, user_msg, sizeof(msg)) )
+		return -1;
+	// TODO: MSG_DONTWAIT and MSG_NOSIGNAL aren't actually supported here!
+	if ( flags & ~(MSG_EOR | MSG_DONTWAIT | MSG_NOSIGNAL) )
+		return errno = EINVAL, -1;
+	if ( msg.msg_name )
+		return errno = EINVAL, -1;
+	if ( msg.msg_control && msg.msg_controllen )
+		return errno = EINVAL, -1;
+	return sys_writev(fd, msg.msg_iov, msg.msg_iovlen);
+}
+
+static ssize_t sys_recvmsg(int fd, struct msghdr* user_msg, int flags)
+{
+	struct msghdr msg;
+	if ( !CopyFromUser(&msg, user_msg, sizeof(msg)) )
+		return -1;
+	if ( flags & ~(MSG_CMSG_CLOEXEC | MSG_DONTWAIT) )
+		return errno = EINVAL, -1;
+	if ( msg.msg_name )
+		return errno = EINVAL, -1;
+	Ref<Descriptor> desc = CurrentProcess()->GetDescriptor(fd);
+	if ( !desc )
+		return -1;
+
+	// TODO: This is not atomic.
+	int old_flags = desc->GetFlags();
+	desc->SetFlags(old_flags | O_NONBLOCK);
+	ssize_t result = sys_readv(fd, msg.msg_iov, msg.msg_iovlen);
+	desc->SetFlags(old_flags);
+
+	msg.msg_flags = 0;
+	if ( !CopyToUser(&user_msg->msg_flags, &msg.msg_flags, sizeof(msg.msg_flags)) )
+		return -1;
+
+	return result;
+}
+
 void Init()
 {
 	Syscall::Register(SYSCALL_ACCEPT4, (void*) sys_accept4);
@@ -1011,8 +1053,10 @@ void Init()
 	Syscall::Register(SYSCALL_READLINKAT, (void*) sys_readlinkat);
 	Syscall::Register(SYSCALL_READ, (void*) sys_read);
 	Syscall::Register(SYSCALL_READV, (void*) sys_readv);
+	Syscall::Register(SYSCALL_RECVMSG, (void*) sys_recvmsg);
 	Syscall::Register(SYSCALL_RECV, (void*) sys_recv);
 	Syscall::Register(SYSCALL_RENAMEAT, (void*) sys_renameat);
+	Syscall::Register(SYSCALL_SENDMSG, (void*) sys_sendmsg);
 	Syscall::Register(SYSCALL_SEND, (void*) sys_send);
 	Syscall::Register(SYSCALL_SETTERMMODE, (void*) sys_settermmode);
 	Syscall::Register(SYSCALL_SYMLINKAT, (void*) sys_symlinkat);

libc/include/sys/socket.h

@@ -137,6 +137,8 @@ struct linger
 #define MSG_PEEK (1<<5)
 #define MSG_TRUNC (1<<6)
 #define MSG_WAITALL (1<<7)
+#define MSG_DONTWAIT (1<<8)
+#define MSG_CMSG_CLOEXEC (1<<9)
 
 #define AF_UNSPEC 0
 #define AF_INET 1

libc/sys/socket/recvmsg.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2013.
+    Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
 
     This file is part of the Sortix C Library.
 
@@ -18,17 +18,19 @@
     along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
 
     sys/socket/recvmsg.cpp
-    Receive a message from a socket.
+    Receive a message on a socket.
 
 *******************************************************************************/
 
 #include <sys/socket.h>
+#include <sys/syscall.h>
 
 #include <errno.h>
 #include <stdio.h>
 
-extern "C" ssize_t recvmsg(int, struct msghdr*, int)
+DEFN_SYSCALL3(ssize_t, sys_recvmsg, SYSCALL_RECVMSG, int, struct msghdr*, int);
+
+extern "C" ssize_t recvmsg(int fd, struct msghdr* msg, int flags)
 {
-	fprintf(stderr, "%s is not implemented yet.\n", __func__);
-	return errno = ENOSYS, -1;
+	return sys_recvmsg(fd, msg, flags);
 }

libc/sys/socket/sendmsg.cpp

@@ -1,6 +1,6 @@
 /*******************************************************************************
 
-    Copyright(C) Jonas 'Sortie' Termansen 2013.
+    Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
 
     This file is part of the Sortix C Library.
 
@@ -23,12 +23,14 @@
 *******************************************************************************/
 
 #include <sys/socket.h>
+#include <sys/syscall.h>
 
 #include <errno.h>
 #include <stdio.h>
 
-extern "C" ssize_t sendmsg(int, const struct msghdr*, int)
+DEFN_SYSCALL3(ssize_t, sys_sendmsg, SYSCALL_SENDMSG, int, const struct msghdr*, int);
+
+extern "C" ssize_t sendmsg(int fd, const struct msghdr* msg, int flags)
 {
-	fprintf(stderr, "%s is not implemented yet.\n", __func__);
-	return errno = ENOSYS, -1;
+	return sys_sendmsg(fd, msg, flags);
 }