px4-firmware/platforms/common/uORB/ORBSet.hpp

158 lines
3.3 KiB
C++

/****************************************************************************
*
* Copyright (c) 2015 Mark Charlebois. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#pragma once
class ORBSet
{
public:
struct Node {
Node *next{nullptr};
const char *node_name{nullptr};
};
ORBSet() = default;
~ORBSet()
{
while (_top != nullptr) {
unlinkNext(_top);
if (_top->next == nullptr) {
free((void *)_top->node_name);
_top->node_name = nullptr;
delete _top;
_top = nullptr;
}
}
}
void insert(const char *node_name)
{
Node **p;
if (_top == nullptr) {
p = &_top;
} else {
p = &_end->next;
}
*p = new Node();
if (_end) {
_end = _end->next;
} else {
_end = _top;
}
_end->next = nullptr;
_end->node_name = strdup(node_name);
}
bool find(const char *node_name)
{
Node *p = _top;
while (p) {
if (strcmp(p->node_name, node_name) == 0) {
return true;
}
p = p->next;
}
return false;
}
bool erase(const char *node_name)
{
Node *p = _top;
if (_top && (strcmp(_top->node_name, node_name) == 0)) {
p = _top->next;
if (_top->node_name) {
free((void *)_top->node_name);
_top->node_name = nullptr;
}
delete _top;
_top = p;
if (_top == nullptr) {
_end = nullptr;
}
return true;
}
while (p->next) {
if (strcmp(p->next->node_name, node_name) == 0) {
unlinkNext(p);
return true;
}
}
return false;
}
private:
void unlinkNext(Node *a)
{
Node *b = a->next;
if (b != nullptr) {
if (_end == b) {
_end = a;
}
a->next = b->next;
if (b->node_name) {
free((void *)b->node_name);
b->node_name = nullptr;
}
delete b;
b = nullptr;
}
}
Node *_top{nullptr};
Node *_end{nullptr};
};