[lttng-tools.git] / src / common / buffer-view.h

/*
 * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License, version 2.1 only,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef LTTNG_BUFFER_VIEW_H
#define LTTNG_BUFFER_VIEW_H

#include <stddef.h>
#include <stdint.h>
#include <common/macros.h>

struct lttng_dynamic_buffer;

struct lttng_buffer_view {
	const char *data;
	size_t size;
};

/**
 * Return a buffer view referencing a subset of the memory referenced by a raw
 * pointer.
 *
 * @src		Source buffer to reference
 * @offset	Offset to apply to the source memory buffer
 * @len		Length of the memory contents to reference.
 *
 * Note that a buffer view never assumes the ownership of the memory it
 * references.
 */
LTTNG_HIDDEN
struct lttng_buffer_view lttng_buffer_view_init(
		const char *src, size_t offset, ptrdiff_t len);

/**
 * Return a buffer view referencing a subset of the memory referenced by another
 * view.
 *
 * @src		Source view to reference
 * @offset	Offset to apply to the source memory content
 * @len		Length of the memory contents to reference. Passing -1 will
 *		cause the view to reference the whole view from the offset
 *		provided.
 *
 * Note that a buffer view never assumes the ownership of the memory it
 * references.
 */
LTTNG_HIDDEN
struct lttng_buffer_view lttng_buffer_view_from_view(
		const struct lttng_buffer_view *src, size_t offset,
		ptrdiff_t len);

/**
 * Return a buffer view referencing a subset of the memory referenced by a
 * dynamic buffer.
 *
 * @src		Source dynamic buffer to reference
 * @offset	Offset to apply to the source memory content
 * @len		Length of the memory contents to reference. Passing -1 will
 *		cause the view to reference the whole dynamic buffer from the
 *		offset provided.
 *
 * Note that a buffer view never assumes the ownership of the memory it
 * references.
 */
LTTNG_HIDDEN
struct lttng_buffer_view lttng_buffer_view_from_dynamic_buffer(
		const struct lttng_dynamic_buffer *src, size_t offset,
		ptrdiff_t len);

#endif /* LTTNG_BUFFER_VIEW_H */
Commit	Line	Data
01dc0eed JG	1	/*
	2	* Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms of the GNU Lesser General Public License, version 2.1 only,
	6	* as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but WITHOUT
	9	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	10	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
	11	* for more details.
	12	*
	13	* You should have received a copy of the GNU Lesser General Public License
	14	* along with this program; if not, write to the Free Software Foundation,
	15	* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	16	*/
	17
	18	#ifndef LTTNG_BUFFER_VIEW_H
	19	#define LTTNG_BUFFER_VIEW_H
	20
	21	#include <stddef.h>
	22	#include <stdint.h>
ff28f865	23	#include <common/macros.h>
01dc0eed JG	24
	25	struct lttng_dynamic_buffer;
	26
	27	struct lttng_buffer_view {
	28	const char *data;
	29	size_t size;
	30	};
	31
b35aac84 JG	32	/**
	33	* Return a buffer view referencing a subset of the memory referenced by a raw
	34	* pointer.
	35	*
	36	* @src Source buffer to reference
	37	* @offset Offset to apply to the source memory buffer
	38	* @len Length of the memory contents to reference.
	39	*
	40	* Note that a buffer view never assumes the ownership of the memory it
	41	* references.
	42	*/
	43	LTTNG_HIDDEN
	44	struct lttng_buffer_view lttng_buffer_view_init(
	45	const char *src, size_t offset, ptrdiff_t len);
	46
01dc0eed JG	47	/**
	48	* Return a buffer view referencing a subset of the memory referenced by another
	49	* view.
	50	*
	51	* @src Source view to reference
	52	* @offset Offset to apply to the source memory content
	53	* @len Length of the memory contents to reference. Passing -1 will
	54	* cause the view to reference the whole view from the offset
	55	* provided.
	56	*
	57	* Note that a buffer view never assumes the ownership of the memory it
	58	* references.
	59	*/
ff28f865	60	LTTNG_HIDDEN
01dc0eed JG	61	struct lttng_buffer_view lttng_buffer_view_from_view(
	62	const struct lttng_buffer_view *src, size_t offset,
	63	ptrdiff_t len);
	64
	65	/**
	66	* Return a buffer view referencing a subset of the memory referenced by a
	67	* dynamic buffer.
	68	*
	69	* @src Source dynamic buffer to reference
	70	* @offset Offset to apply to the source memory content
	71	* @len Length of the memory contents to reference. Passing -1 will
	72	* cause the view to reference the whole dynamic buffer from the
	73	* offset provided.
	74	*
	75	* Note that a buffer view never assumes the ownership of the memory it
	76	* references.
	77	*/
ff28f865	78	LTTNG_HIDDEN
01dc0eed JG	79	struct lttng_buffer_view lttng_buffer_view_from_dynamic_buffer(
	80	const struct lttng_dynamic_buffer *src, size_t offset,
	81	ptrdiff_t len);
	82
	83	#endif /* LTTNG_BUFFER_VIEW_H */