syscall: multiple syscalls related to sockets

kernel-src/sys/syscalls/socket.c

@@ -0,0 +1,58 @@
+#include <kernel/syscalls.h>
+#include <kernel/abi.h>
+#include <kernel/sock.h>
+#include <errno.h>
+
+syscallret_t syscall_socket(context_t *, int domain, int type, int protocol) {
+	syscallret_t ret = {
+		.ret = -1
+	};
+
+	int socktype = -1;
+
+	switch (domain) {
+		case AF_INET:
+			if (type != SOCK_DGRAM)
+				break;
+
+			socktype = SOCKET_TYPE_UDP;
+			break;
+	}
+
+	if (socktype == -1) {
+		ret.errno = EAFNOSUPPORT;
+		return ret;
+	}
+
+	socket_t *socket = socket_create(socktype);
+	if (socket == NULL) {
+		ret.errno = ENOMEM;
+		return ret;
+	}
+
+	vnode_t *vnode;
+	ret.errno = sockfs_newsocket(&vnode, socket);
+	if (ret.errno) {
+		// TODO delete socket
+		return ret;
+	}
+
+	file_t *file;
+	int fd;
+	
+	ret.errno = fd_new(0, &file, &fd);
+	if (ret.errno) {
+		// socket gets deleted by node cleanup
+		VOP_RELEASE(vnode);
+		return ret;
+	}
+
+	file->vnode = vnode;
+	file->flags = FILE_READ | FILE_WRITE;
+	file->offset = 0;
+	file->mode = 0777;
+
+	ret.ret = fd;
+
+	return ret;
+}