Astral/kernel-src/sys/syscalls/setsockopt.c

#include <kernel/syscalls.h>
#include <kernel/sock.h>
#include <kernel/abi.h>
#include <kernel/file.h>
#include <kernel/usercopy.h>
#include <errno.h>

syscallret_t syscall_setsockopt(context_t *, int fd, int level, int optname, void *val, size_t len) {
	syscallret_t ret = {
		.ret = -1
	};

	file_t *file = fd_get(fd);
	if (file == NULL) {
		ret.errno = EBADF;
		return ret;
	}

	if (file->vnode->type != V_TYPE_SOCKET) {
		ret.errno = ENOTSOCK;
		goto cleanup;
	}

	socket_t *socket = SOCKFS_SOCKET_FROM_NODE(file->vnode); 

	MUTEX_ACQUIRE(&socket->mutex);
	if (level == SOL_SOCKET) {
		// handle some generic cases here
		switch (optname) {
			case SO_BINDTODEVICE: {
				if (val) {
					size_t size;
					ret.errno = usercopy_strlen(val, &size);
					if (ret.errno)
						break;

					if (size > 32) {
						ret.errno = EINVAL;
						break;
					}

					char name[size + 1];
					ret.errno = usercopy_fromuser(name, val, size);
					if (ret.errno)
						break;
					name[size] = '\0';

					socket->netdev = netdev_getdev(name);
					ret.errno = socket->netdev ? 0 : ENODEV;
				} else {
					socket->netdev = NULL;
				}
				break;
			}
			case SO_BROADCAST: {
				ret.errno = usercopy_fromuser(&socket->broadcast, val, sizeof(int));
				break;
			}
			default:
				ret.errno = socket->ops->setopt ? socket->ops->setopt(socket, level, optname, val, len, &current_thread()->proc->cred) : ENOPROTOOPT;
		}
	} else {
		ret.errno = socket->ops->setopt ? socket->ops->setopt(socket, level, optname, val, len, &current_thread()->proc->cred) : ENOPROTOOPT;
	}

	MUTEX_RELEASE(&socket->mutex);

	cleanup:
	ret.ret = ret.errno ? -1 : 0;

	fd_release(file);

	return ret;
}