syscalls: getsockopt

kernel-src/sys/syscalls/getsockopt.c

@@ -0,0 +1,66 @@
+#include <kernel/syscalls.h>
+#include <kernel/sock.h>
+#include <kernel/abi.h>
+#include <kernel/file.h>
+#include <errno.h>
+
+syscallret_t syscall_getsockopt(context_t *, int fd, int level, int optname, void *val, socklen_t *len) {
+	syscallret_t ret = {
+		.ret = -1
+	};
+
+	if (!IS_USER_ADDRESS(val) || !IS_USER_ADDRESS(len)) {
+		ret.errno = EFAULT;
+	}
+
+	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 general cases
+		switch (optname) {
+			case SO_ERROR: {
+				socklen_t l;
+				ret.errno = usercopy_fromuser(&l, len, sizeof(l));
+				if (ret.errno)
+					break;
+
+				if (l != 4) {
+					ret.errno = EINVAL;
+					break;
+				}
+
+				int error = socket->error;
+				ret.errno = usercopy_touser(val, &error, sizeof(error));
+				if (!ret.errno)
+					socket->error = 0;
+
+				break;
+			}
+			default: {
+				ret.errno = socket->ops->getopt ? socket->ops->getopt(socket, level, optname, val, len, &current_thread()->proc->cred) : ENOPROTOOPT;
+			}
+		}
+	} else {
+		ret.errno = socket->ops->getopt ? socket->ops->getopt(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;
+}