+++ /dev/null
-/*
- * 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_DYNAMIC_BUFFER_H
-#define LTTNG_DYNAMIC_BUFFER_H
-
-#include <stddef.h>
-#include <stdint.h>
-#include <common/macros.h>
-
-struct lttng_dynamic_buffer {
- char *data;
- /* size is the buffer's currently used capacity. */
- size_t size;
- /*
- * capacity shall not be accessed by users directly, it is meant for
- * internal use only.
- */
- size_t _capacity;
-};
-
-/*
- * Initialize a dynamic buffer. This performs no allocation and is meant
- * to be used instead of memset or explicit initialization of the buffer.
- */
-LTTNG_HIDDEN
-void lttng_dynamic_buffer_init(struct lttng_dynamic_buffer *buffer);
-
-/*
- * Append the content of a raw memory buffer to the end of a dynamic buffer
- * (after its current "size"). The dynamic buffer's size is increased by
- * "len", and its capacity is adjusted automatically.
- */
-LTTNG_HIDDEN
-int lttng_dynamic_buffer_append(struct lttng_dynamic_buffer *buffer,
- const void *buf, size_t len);
-
-/*
- * Performs the same action as lttng_dynamic_buffer_append(), but using another
- * dynamic buffer as the source buffer. The source buffer's size is used in lieu
- * of "len".
- */
-LTTNG_HIDDEN
-int lttng_dynamic_buffer_append_buffer(struct lttng_dynamic_buffer *dst_buffer,
- struct lttng_dynamic_buffer *src_buffer);
-
-/*
- * Set the buffer's size to new_size. The capacity of the buffer will
- * be expanded (if necessary) to accomodate new_size. Areas acquired by
- * a size increase will be zeroed.
- *
- * Be careful to expand the buffer's size _before_ calling out external
- * APIs (e.g. read(3)) which may populate the buffer as setting the size
- * after will zero-out the result of the operation.
- *
- * Shrinking a buffer does not zero the old content. If the buffer may contain
- * sensititve information, it must be cleared manually _before_ changing the
- * size.
- *
- * NOTE: It is striclty _invalid_ to access memory after _size_, regardless
- * of prior calls to set_capacity().
- */
-LTTNG_HIDDEN
-int lttng_dynamic_buffer_set_size(struct lttng_dynamic_buffer *buffer,
- size_t new_size);
-
-/*
- * Set the buffer's capacity to accomodate the new_capacity, allocating memory
- * as necessary. The buffer's content is preserved. Setting a buffer's capacity
- * is meant as a _hint_ to the underlying buffer and is only optimization; no
- * guarantee is offered that subsequent calls to append or set_size will succeed.
- *
- * If the current size > new_capacity, the operation will fail.
- */
-LTTNG_HIDDEN
-int lttng_dynamic_buffer_set_capacity(struct lttng_dynamic_buffer *buffer,
- size_t new_capacity);
-
-/* Release any memory used by the dynamic buffer. */
-LTTNG_HIDDEN
-void lttng_dynamic_buffer_reset(struct lttng_dynamic_buffer *buffer);
-
-/* Get the space left in the buffer before a new resize is needed. */
-LTTNG_HIDDEN
-size_t lttng_dynamic_buffer_get_capacity_left(
- struct lttng_dynamic_buffer *buffer);
-
-#endif /* LTTNG_DYNAMIC_BUFFER_H */
projects / lttng-tools.git / blobdiff