Add the trace chunk and trace chunk registry interfaces

[lttng-tools.git] / src / common / dynamic-array.h

/*
 * Copyright (C) 2019 - 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_DYNAMIC_ARRAY_H
#define LTTNG_DYNAMIC_ARRAY_H

#include <common/dynamic-buffer.h>
#include <assert.h>

struct lttng_dynamic_array {
	struct lttng_dynamic_buffer buffer;
	size_t element_size;
	size_t size;
};

struct lttng_dynamic_pointer_array {
	struct lttng_dynamic_array array;
};

typedef void (*lttng_dynamic_array_element_destructor)(void *element);
typedef void (*lttng_dynamic_pointer_array_destructor)(void *ptr);

/*
 * Initialize a resizable array of fixed-size elements. This performs no
 * allocation and can't fail.
 */
LTTNG_HIDDEN
void lttng_dynamic_array_init(struct lttng_dynamic_array *array,
		size_t element_size);

/*
 * Returns the number of elements in the dynamic array.
 */
static inline
size_t lttng_dynamic_array_get_count(
		const struct lttng_dynamic_array *array)
{
	return array->size;
}

/*
 * Returns a pointer to the element. Mutating operations on the array invalidate
 * the returned pointer.
 */
static inline
void *lttng_dynamic_array_get_element(const struct lttng_dynamic_array *array,
		size_t element_index)
{
	assert(element_index < array->size);
	return array->buffer.data + (element_index * array->element_size);
}

/*
 * Add an element to the end of a dynamic array. The array's element count is
 * increased by one and its underlying capacity is adjusted automatically.
 *
 * element is a pointer to the element to add (copy) to the array.
 */
LTTNG_HIDDEN
int lttng_dynamic_array_add_element(struct lttng_dynamic_array *array,
		const void *element);

/* Release any memory used by the dynamic array. */
LTTNG_HIDDEN
void lttng_dynamic_array_reset(struct lttng_dynamic_array *array,
		lttng_dynamic_array_element_destructor destructor);


/*
 * Specialization of lttng_dynamic_array for pointers. This utility
 * is built under the assumption that pointer sizes are equal
 * for all data types on supported architectures. Revisit this in the event
 * of a port to an Harvard architecture.
 */

/*
 * Initialize a resizable array of fixed-size elements. This performs no
 * allocation and can't fail.
 */
LTTNG_HIDDEN
void lttng_dynamic_pointer_array_init(
		struct lttng_dynamic_pointer_array *array);

/*
 * Returns the number of pointers in the dynamic pointer array.
 */
static inline
size_t lttng_dynamic_pointer_array_get_count(
		const struct lttng_dynamic_pointer_array *array)
{
	return lttng_dynamic_array_get_count(&array->array);
}

/*
 * Returns a pointer to the element. Mutating operations on the array invalidate
 * the returned pointer.
 */
static inline
void *lttng_dynamic_pointer_array_get_pointer(
		const struct lttng_dynamic_pointer_array *array, size_t index)
{
	void **element = lttng_dynamic_array_get_element(&array->array, index);

	return *element;
}

/*
 * Add a pointer to the end of a dynamic pointer array. The array's element
 * count is increased by one and its underlying capacity is adjusted
 * automatically.
 */
static inline
int lttng_dynamic_pointer_array_add_pointer(
		struct lttng_dynamic_pointer_array *array, void *pointer)
{
	return lttng_dynamic_array_add_element(&array->array, &pointer);
}

/* Release any memory used by the dynamic array. */
LTTNG_HIDDEN
void lttng_dynamic_pointer_array_reset(
		struct lttng_dynamic_pointer_array *array,
		lttng_dynamic_pointer_array_destructor destructor);

#endif /* LTTNG_DYNAMIC_ARRAY_H */