本周包了饺子,辣椒油整的也不错,不过包饺子上升的空间还很大。
饺子美照:


一、linux下Qt treeView内存泄漏
当把原来Qt程序由ubuntu 32位的程序迁移到ubuntu 64位时,测试程序发现了内存泄漏问题,经过排查,最终定位在Qt的treeView的setCurrentIndex调用上。到目前还没有排查出来,有遇到同样问题的同志可以一起交流下。程序测试demo在64位环境下有明显内存泄漏,但是同样程序在32位上运行正常,接下来可能要继续更换Qt的版本进行测试了。
目前推测就是Qt自身Widget库的问题。
测试环境:Linux ubuntu 4.15.0-142-generic #146~16.04.1-Ubuntu
测试程序如下:
头文件:
- /****************************************************************************
- **
- ** Copyright (C) 2016 The Qt Company Ltd.
- ** Contact: https://www.qt.io/licensing/
- **
- ** This file is part of the examples of the Qt Toolkit.
- **
- ** $QT_BEGIN_LICENSE:BSD$
- ** Commercial License Usage
- ** Licensees holding valid commercial Qt licenses may use this file in
- ** accordance with the commercial license agreement provided with the
- ** Software or, alternatively, in accordance with the terms contained in
- ** a written agreement between you and The Qt Company. For licensing terms
- ** and conditions see https://www.qt.io/terms-conditions. For further
- ** information use the contact form at https://www.qt.io/contact-us.
- **
- ** BSD License Usage
- ** Alternatively, you may use this file under the terms of the BSD license
- ** as follows:
- **
- ** "Redistribution and use in source and binary forms, with or without
- ** modification, are permitted provided that the following conditions are
- ** met:
- ** * Redistributions of source code must retain the above copyright
- ** notice, this list of conditions and the following disclaimer.
- ** * 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.
- ** * Neither the name of The Qt Company Ltd 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."
- **
- ** $QT_END_LICENSE$
- **
- ****************************************************************************/
-
-
- #ifndef MAINWINDOW_H
- #define MAINWINDOW_H
-
-
- #include
- #include
- #include
-
-
- QT_BEGIN_NAMESPACE
- class QTreeView; //forward declarations
- class QStandardItemModel;
- class QStandardItem;
- class QTimer;
-
-
- QT_END_NAMESPACE
-
-
-
-
- class MainWindow : public QMainWindow
- {
- Q_OBJECT
-
-
- private slots:
- void slot_valueIncrease();
- void slot_modelIndex(QModelIndex index);
-
-
- private:
- QTreeView *treeView;
-
-
- QTreeView TreeView;
-
-
- QStandardItemModel *standardModel;
- QList
prepareRow(const QString &first) const ; -
-
- QTimer *timer_;
- int count{0};
-
-
- QStandardItem *root_;
- QStandardItem *first_;
- QStandardItem *second_;
-
-
-
-
- public:
- MainWindow(QWidget *parent = nullptr);
- };
-
-
- #endif // MAINWINDOW_H
cpp文件:
- root_ = new QStandardItem("root");
- first_ = new QStandardItem("first");
- second_ = new QStandardItem("second");
-
-
- first_->appendRow(second_);
- root_->appendRow(first_);
- 定时器溢出后:
- treeView->setCurrentIndex(first_->index());
- treeView->setCurrentIndex(second_->index());
最后使用top指令观察RES值,会有明显连续增加。程序运行效果:

二、linux下
linux下USB转232、转485、转422的硬件验证
RS232 DB9接头2脚和三脚短接,实现“环回”
RS485 是半双工,无法环回。
RS422 DB9接头,短接13 短接24。
引脚具体图片:

RS232

RS422
Linux脚本测试指令:
1、利用stty命令去掉默认的回显参数
stty -F /dev/ttyUSB0 -echo -onlcr
2、一个终端输入:
cat /dev/ttyUSB0
1、另一个终端输入
echo "hello" > /dev/ttyUSB0
效果如图:




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