--- /dev/null
+/*
+ * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#ifndef LTTNG_PAYLOAD_H
+#define LTTNG_PAYLOAD_H
+
+#include <common/dynamic-buffer.hpp>
+#include <common/dynamic-array.hpp>
+#include <common/fd-handle.hpp>
+
+/*
+ * An lttng_payload encompasses the 'data' (bytes) and any passed file
+ * descriptors as part of a message between liblttng-ctl and the session
+ * daemon.
+ */
+struct lttng_payload {
+ struct lttng_dynamic_buffer buffer;
+ /* private */
+ struct lttng_dynamic_pointer_array _fd_handles;
+};
+
+/*
+ * Initialize a payload. This performs no allocation and is meant
+ * to be used instead of zero-ing the payload structure.
+ */
+void lttng_payload_init(struct lttng_payload *payload);
+
+/* Copy a payload. */
+int lttng_payload_copy(const struct lttng_payload *src_payload,
+ struct lttng_payload *dst_payload);
+
+/* Release any memory and references held by the payload. */
+void lttng_payload_reset(struct lttng_payload *payload);
+
+/*
+ * Empty the contents of a payload, releasing all references held.
+ * This should be used to put a payload in a re-usable state.
+ *
+ * lttng_payload_reset must still be called on an lttng_payload to
+ * free all allocated memory.
+ */
+void lttng_payload_clear(struct lttng_payload *payload);
+
+/**
+ * Add an fd to the payload.
+ * The payload acquires a reference to the fd_handle.
+ *
+ * @payload Payload instance
+ * @fd_handle File descriptor handle to add to the payload
+ *
+ * Returns 0 on success, -1 on allocation error.
+ */
+int lttng_payload_push_fd_handle(struct lttng_payload *payload,
+ struct fd_handle *fd_handle);
+
+#endif /* LTTNG_PAYLOAD_H */