-/*
- * objstack.c
- *
- * Common Trace Format Object Stack.
- *
- * Copyright 2013 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-#include <stdlib.h>
-#include <babeltrace/list.h>
-#include <babeltrace/babeltrace-internal.h>
-#include <babeltrace/align.h>
-
-#define OBJSTACK_ALIGN 8 /* Object stack alignment */
-#define OBJSTACK_INIT_LEN 128
-#define OBJSTACK_POISON 0xcc
-
-struct objstack {
- struct bt_list_head head; /* list of struct objstack_node */
-};
-
-struct objstack_node {
- struct bt_list_head node;
- size_t len;
- size_t used_len;
- char __attribute__ ((aligned (OBJSTACK_ALIGN))) data[];
-};
-
-BT_HIDDEN
-struct objstack *objstack_create(void)
-{
- struct objstack *objstack;
- struct objstack_node *node;
-
- objstack = calloc(1, sizeof(*objstack));
- if (!objstack)
- return NULL;
- node = calloc(sizeof(struct objstack_node) + OBJSTACK_INIT_LEN,
- sizeof(char));
- if (!node) {
- free(objstack);
- return NULL;
- }
- BT_INIT_LIST_HEAD(&objstack->head);
- bt_list_add_tail(&node->node, &objstack->head);
- node->len = OBJSTACK_INIT_LEN;
- return objstack;
-}
-
-static
-void objstack_node_free(struct objstack_node *node)
-{
- size_t offset, len;
- char *p;
-
- if (!node)
- return;
- p = (char *) node;
- len = sizeof(*node) + node->len;
- for (offset = 0; offset < len; offset++)
- p[offset] = OBJSTACK_POISON;
- free(node);
-}
-
-BT_HIDDEN
-void objstack_destroy(struct objstack *objstack)
-{
- struct objstack_node *node, *p;
-
- if (!objstack)
- return;
- bt_list_for_each_entry_safe(node, p, &objstack->head, node) {
- bt_list_del(&node->node);
- objstack_node_free(node);
- }
- free(objstack);
-}
-
-static
-struct objstack_node *objstack_append_node(struct objstack *objstack)
-{
- struct objstack_node *last_node, *new_node;
-
- /* Get last node */
- last_node = bt_list_entry(objstack->head.prev,
- struct objstack_node, node);
-
- /* Allocate new node with double of size of last node */
- new_node = calloc(sizeof(struct objstack_node) + (last_node->len << 1),
- sizeof(char));
- if (!new_node) {
- return NULL;
- }
- bt_list_add_tail(&new_node->node, &objstack->head);
- new_node->len = last_node->len << 1;
- return new_node;
-}
-
-BT_HIDDEN
-void *objstack_alloc(struct objstack *objstack, size_t len)
-{
- struct objstack_node *last_node;
- void *p;
-
- len = ALIGN(len, OBJSTACK_ALIGN);
-
- /* Get last node */
- last_node = bt_list_entry(objstack->head.prev,
- struct objstack_node, node);
- while (last_node->len - last_node->used_len < len) {
- last_node = objstack_append_node(objstack);
- if (!last_node) {
- return NULL;
- }
- }
- p = &last_node->data[last_node->used_len];
- last_node->used_len += len;
- return p;
-}