+++ /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
- */
-
-#include <common/dynamic-buffer.h>
-#include <common/macros.h>
-#include <common/utils.h>
-#include <assert.h>
-
-static
-size_t round_to_power_of_2(size_t val)
-{
- int order;
- size_t rounded;
-
- order = utils_get_count_order_u64(val);
- assert(order >= 0);
- rounded = (1ULL << order);
- assert(rounded >= val);
-
- return rounded;
-}
-
-void lttng_dynamic_buffer_init(struct lttng_dynamic_buffer *buffer)
-{
- assert(buffer);
- memset(buffer, 0, sizeof(*buffer));
-}
-
-int lttng_dynamic_buffer_append(struct lttng_dynamic_buffer *buffer,
- const void *buf, size_t len)
-{
- int ret = 0;
-
- if (!buffer || (!buf && len)) {
- ret = -1;
- goto end;
- }
-
- if (len == 0) {
- /* Not an error, no-op. */
- goto end;
- }
-
- assert(buffer->capacity >= buffer->size);
- if (buffer->capacity < (len + buffer->size)) {
- ret = lttng_dynamic_buffer_set_capacity(buffer,
- buffer->capacity +
- (len - (buffer->capacity - buffer->size)));
- if (ret) {
- goto end;
- }
- }
-
- memcpy(buffer->data + buffer->size, buf, len);
- buffer->size += len;
-end:
- return ret;
-}
-
-int lttng_dynamic_buffer_append_buffer(struct lttng_dynamic_buffer *dst_buffer,
- struct lttng_dynamic_buffer *src_buffer)
-{
- int ret;
-
- if (!dst_buffer || !src_buffer) {
- ret = -1;
- goto end;
- }
-
- ret = lttng_dynamic_buffer_append(dst_buffer, src_buffer->data,
- src_buffer->size);
-end:
- return ret;
-}
-
-int lttng_dynamic_buffer_set_size(struct lttng_dynamic_buffer *buffer,
- size_t new_size)
-{
- int ret = 0;
-
- if (!buffer) {
- goto end;
- }
-
- if (new_size == buffer->size) {
- goto end;
- }
-
- if (new_size > buffer->capacity) {
- size_t original_size = buffer->size;
- size_t original_capacity = buffer->capacity;
-
- ret = lttng_dynamic_buffer_set_capacity(buffer, new_size);
- if (ret) {
- goto end;
- }
-
- /*
- * Zero-initialize the space that was left in the buffer at the
- * before we increased its capacity (original capacity - original size).
- * The newly acquired capacity (new capacity - original capacity)
- * is zeroed by lttng_dynamic_buffer_set_capacity().
- */
- memset(buffer->data + original_size, 0,
- original_capacity - original_size);
- } else if (new_size > buffer->size) {
- memset(buffer->data + buffer->size, 0, new_size - buffer->size);
- } else {
- /*
- * Shrinking size. There is no need to zero-out the newly
- * released memory as it will either be:
- * - overwritten by lttng_dynamic_buffer_append,
- * - expanded later, which will zero-out the memory
- *
- * Users of external APIs are encouraged to set the buffer's
- * size _before_ making such calls.
- */
- }
- buffer->size = new_size;
-end:
- return ret;
-}
-
-int lttng_dynamic_buffer_set_capacity(struct lttng_dynamic_buffer *buffer,
- size_t new_capacity)
-{
- int ret = 0;
- size_t rounded_capacity = round_to_power_of_2(new_capacity);
-
- if (!buffer || new_capacity < buffer->size) {
- ret = -1;
- goto end;
- }
-
- if (rounded_capacity == buffer->capacity) {
- goto end;
- }
-
- if (!buffer->data) {
- buffer->data = zmalloc(rounded_capacity);
- if (!buffer->data) {
- ret = -1;
- goto end;
- }
- } else {
- void *new_buf;
-
- new_buf = realloc(buffer->data, rounded_capacity);
- if (new_buf) {
- if (rounded_capacity > buffer->capacity) {
- memset(new_buf + buffer->capacity, 0,
- rounded_capacity - buffer->capacity);
- }
- } else {
- /* Realloc failed, try to acquire a new block. */
- new_buf = zmalloc(rounded_capacity);
- if (!new_buf) {
- ret = -1;
- goto end;
- }
- memcpy(new_buf, buffer->data, buffer->size);
- free(buffer->data);
- }
- buffer->data = new_buf;
- }
- buffer->capacity = rounded_capacity;
-end:
- return ret;
-}
-
-/* Release any memory used by the dynamic buffer. */
-void lttng_dynamic_buffer_reset(struct lttng_dynamic_buffer *buffer)
-{
- if (!buffer) {
- return;
- }
- buffer->size = 0;
- buffer->capacity = 0;
- free(buffer->data);
-}
projects / lttng-tools.git / blobdiff