[pulseview.git] / pv / data / snapshot.h

/*
 * This file is part of the PulseView project.
 *
 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#ifndef PULSEVIEW_PV_DATA_SNAPSHOT_H
#define PULSEVIEW_PV_DATA_SNAPSHOT_H

#include <libsigrok/libsigrok.h>

#include <thread>
#include <mutex>

namespace pv {
namespace data {

class Snapshot
{
public:
	Snapshot(int unit_size);

	virtual ~Snapshot();

	uint64_t get_sample_count() const;

	int unit_size() const;

	/**
	 * @brief Increase the capacity of the snapshot.
	 *
	 * Increasing the capacity allows samples to be appended without needing
	 * to reallocate memory.
	 *
	 * For the best efficiency @c set_capacity() should be called once before
	 * @c append_data() is called to set up the snapshot with the expected number
	 * of samples that will be appended in total.
	 *
	 * @note The capacity will automatically be increased when @c append_data()
	 * is called if there is not enough capacity in the buffer to store the samples.
	 *
	 * @param[in] new_capacity The new capacity of the snapshot. If this value is
	 * 	smaller or equal than the current capacity then the method has no effect.
	 */
	void set_capacity(uint64_t new_capacity);

	/**
	 * @brief Get the current capacity of the snapshot.
	 *
	 * The capacity can be increased by calling @c set_capacity().
	 *
	 * @return The current capacity of the snapshot.
	 */
	uint64_t capacity() const;

protected:
	void append_data(void *data, uint64_t samples);

protected:
	mutable std::recursive_mutex _mutex;
	void *_data;
	uint64_t _sample_count;
	uint64_t _capacity;
	int _unit_size;
};

} // namespace data
} // namespace pv

#endif // PULSEVIEW_PV_DATA_SNAPSHOT_H
Commit	Line	Data
	1	/*
	2	* This file is part of the PulseView project.
	3	*
	4	* Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*/
	20
	21	#ifndef PULSEVIEW_PV_DATA_SNAPSHOT_H
	22	#define PULSEVIEW_PV_DATA_SNAPSHOT_H
	23
	24	#include <libsigrok/libsigrok.h>
	25
	26	#include <thread>
	27	#include <mutex>
	28
	29	namespace pv {
	30	namespace data {
	31
	32	class Snapshot
	33	{
	34	public:
	35	Snapshot(int unit_size);
	36
	37	virtual ~Snapshot();
	38
	39	uint64_t get_sample_count() const;
	40
	41	int unit_size() const;
	42
	43	/**
	44	* @brief Increase the capacity of the snapshot.
	45	*
	46	* Increasing the capacity allows samples to be appended without needing
	47	* to reallocate memory.
	48	*
	49	* For the best efficiency @c set_capacity() should be called once before
	50	* @c append_data() is called to set up the snapshot with the expected number
	51	* of samples that will be appended in total.
	52	*
	53	* @note The capacity will automatically be increased when @c append_data()
	54	* is called if there is not enough capacity in the buffer to store the samples.
	55	*
	56	* @param[in] new_capacity The new capacity of the snapshot. If this value is
	57	* smaller or equal than the current capacity then the method has no effect.
	58	*/
	59	void set_capacity(uint64_t new_capacity);
	60
	61	/**
	62	* @brief Get the current capacity of the snapshot.
	63	*
	64	* The capacity can be increased by calling @c set_capacity().
	65	*
	66	* @return The current capacity of the snapshot.
	67	*/
	68	uint64_t capacity() const;
	69
	70	protected:
	71	void append_data(void *data, uint64_t samples);
	72
	73	protected:
	74	mutable std::recursive_mutex _mutex;
	75	void *_data;
	76	uint64_t _sample_count;
	77	uint64_t _capacity;
	78	int _unit_size;
	79	};
	80
	81	} // namespace data
	82	} // namespace pv
	83
	84	#endif // PULSEVIEW_PV_DATA_SNAPSHOT_H