Filling Complex Polygons by Region-Fill Methods on Raster Graphics Terminals

A method is described for filling polygons according to the GKS Fill Area definition on terminals that provide only region-filling capabilities. The advantages and disadvantages of using this algorithm in GKS device drivers are considered.     

On developing a GKS driver architecture for raster workstations

The use of raster graphics devices needs adapting to graphics applications. The first graphics standard, the Graphics Kernel System GKS, defines a logical interface on an application and device independent level. The workstation driver maps the logical GKS functions to device functions. First some special raster device facilities are outlined and then it is shown how to use them within the driver. To reduce the amount of driver implementations a common driver concept is sought here, especially for raster devices.     

基于虚拟机的透明计算设备子系统设计及实现*

为解决在现有透明计算系统中磁盘等设备的虚拟化,需要对操作系统进行修改才能在端计算机上运行的问题,提出透明计算系统中一种基于虚拟机技术的设备子系统。以Intel VT硬件级虚拟支持和Xen虚拟化技术为基础, 在全虚拟化的虚拟机上运行用户操作系统: 通过运行在管理域用户空间中设备模型的虚拟磁盘和网络驱动,将用户域访问磁盘和网络的I/O请求跨网络地重定向到服务器进行处理, 从而实现端计算机上多操作系统的远程运行。在VT硬件平台和Xen虚拟机监控器上实现了原型系统,验证了该方法的可行性。     

Evaluation of Standard Graphics Packages

In order to compare the quality of different implementations of GKS, the ISO0 standard for computer graphics, an evaluation method for GKS implementations is presented. It is based upon several groups of criteria. One group of criteria is concerned with performance, by which we understand here the memory requirements and time requirements for programs using GKS functions. A program that measures the performance of GKS packages is presented. Results of this evaluation method with several commercially available GKS implementations are described in summary. A checklist for evaluation of standard graphics packages is added as an appendix.     

Some Aspects of Binding GKS to C++

Aspects of a prototype binding of GKS to the C++ programming language are presented. The binding makes use of classes and derived classes to define GKS concepts such as segments and workstations. Operator overloading is used for some GKS Functions.     

Conformance specification in the CGI

The Computer Graphics Interface (CGI) is a developing International Organization for Standardization (ISO) standard proposal¹ that addresses the interface between a virtual graphics device and an implementation of one of the ISO functional standards (namely, Programmer's Hierarchical Interactive Graphics System (PHIGS)², Graphical Kernel System (GKS)³, and Graphical Kernel System for Three Dimensions (GKS-3D)⁴. This paper may interest those who are tracking the development of the CGI and describes a recently introduced method for structuring conformance to provide for a wide diversity of device technology and architecture, while also providing for the spread of functional specification requirements. This scheme involves the definition of a number of standard constituency profiles, and pays particular attention to the needs of GKS and the Computer Graphics Metafile (CGM)⁵ in accessing the virtual device through the CGI. It must be stressed that the CGI is an emerging standard, and has not yet achieved a state of technical stability.     

A verifier for checking the conformance of programs with the GKS standard

A software development tool is introduced which allows to check the corrections of programs using the Graphical Kernel System (GKS). Such graphical application programs are checked whether their use of GKS functions is syntactically correct and conforms with semantic rules given by the GKS definition. Like the PFORT verifier for FORTRAN programs, this tool greatly reduces development time for GKS programs.     

Linux设备驱动程序自动更新及辅助工具

研究了Linux设备驱动程序的自动更新方法,建立了基于源码的Linux设备驱动辅助更新模型,设计并实现了一组相应的自动更新支撑工具,包括Linux设备驱动程序对内核依赖接口的分析工具、内核依赖接口差异性分析工具以及设备驱动更新辅助信息的生成工具.相关原型经测试验证表明,可以有效改善设备驱动开发和维护工作.另外,还提出了用于评估设备驱动辅助更新工作的量化指标即关于辅助更新提示信息的误报率和漏报率的概念及计算方法.     

Realization and Application of an Intelligent GKS Workstation

This articles summarizes the work at SIGMEX Systems Limited from its origin in 1982 just prior to the publication of the draft of the International Graphics Standard, GKS. This article covers the original concept of the GKS workstation as defined in the Standard, its realization, the practical implications, and the real-world application of the resulting intelligent workstation device.     

A Multi-Microprocessor GKS Workstation

Implementers of graphical application sytems hesitate to interface their applications to the GKS standard not only because GKS functionality seems to be less suffcient for a particular application but also because the use of GKS-as it is offered in portable software implementions-uaually means a loss of system performance. This article describes an installation of GKS on a multi-microprocessor that is based on functional distribution principles as well as on the object-oriented distribution of a graphics system. The main concepts and advantages of a GKS workstation using more than one processing unit with at least one output pipeline are described. The flexibility of this approach opens a perspective view to a GKS workststion that is configurable to application requirements.     

Linux设备驱动重用研究

设备驱动是影响操作系统适用性的重要因素。考虑到完全重新开发设备驱动代价过大,重用已有操作系统中的设备驱动便成为了提高操作系统适用性的首选方法。设备驱动的重用过程本质上是在目标环境中建立设备驱动的运行环境的过程,重用一个设备驱动并不需要实现所有内核服务。代码依赖分析可以分析驱动代码对内核服务的依赖关系,因此可以使用代码依赖分析技术自动构建设备驱动运行环境。通过在嵌入式操作系统ucore OS中重用e1000网卡驱动来证明方法的可行性。     

基于配对函数调用场景的设备驱动漏洞检测

由于Linux系统的设备驱动工作在内核模式中,在这种特定的工作场景下,由设备驱动引发的漏洞问题极易影响操作系统的稳定性和安全性.当前在各类设备驱动漏洞中所占比例较高的当属资源操作类漏洞,针对这种情况,我们提出了一种基于配对函数调用场景的设备驱动漏洞检测方法.首先引入配对函数的概念,据此对特定的驱动程序做配对函数的自动提取与优化;随后结合手工分析结果构建配对函数在资源申请与释放过程中的执行路径;最后基于相应的函数调用场景进行配对检查,检测并验证设备驱动程序中内存资源的申请和释放是否为完全层次性匹配.为验证该方法的有效性,实验分别选取不同的设备驱动应用该漏洞检测方法,记录相应的漏报率、误报率及覆盖度.实验结果表明,该设备驱动漏洞检测方法精确率较高,检测速度快.并且该方法不依赖于实时编译以及硬件设备等条件.     

基于性质制导符号执行的Linux驱动程序缺陷检测研究

驱动程序是操作系统的重要组成部分。驱动程序运行于内核态,其可靠性对于操作系统的安全可靠非常关键。针对Linux驱动程序,研究基于符号执行的驱动程序缺陷自动检测方法。提出了基于性质制导符号执行的Linux驱动程序缺陷检测框架,以及多性质制导的符号执行方法,支持针对多个缺陷性质的快速缺陷检测。在LLVM和KLEE的基础上实现了提出的框架和方法,并在实际的Linux驱动程序上开展了初步实验。实验效果表明了所提方法和检测框架的有效性和高效性。     

Linx下PCI设备驱动程序研究

在简要概括Linux下设备驱动程序的原理和相关知识的基础上 ,提出了编写一个PCI驱动程序的流程图和框架 ;并通过设计和实现一个具体而典型的例子 ,总结了在Linux下编写一个PCI设备驱动程序的一般方法和技巧 ;最后用一个简单的应用程序做了实验。     

Linux下USB设备驱动研究与开发

开发USB(Universal Serial Bus)设备驱动是一项比较繁琐的工作。Linux中的USB核心子系统提供了大量的API以及相关的支持机制，保证了USB设备的即插即用，简化了驱动的编写。结合具体开发实例，介绍了USB的相关概念，分析Linux中USB核心子系统的框架构成以及重要的数据结构，剖析Linux内核对USB规范的支持，描述了驱动开发的一般方法和技巧。     

基于COM的组态软件I/O设备驱动程序设计

详细介绍了一种基于COM组件技术的组态软件I/O设备驱动程序的设计方法。在分析了设计原理的基础上,给出了一种以太网数据服务器驱动程序的具体实现。COM组件驱动程序的进程内运行方式和被所有驱动程序组件支持的统一的协议接口,在组态软件和设备驱动程序之间建立了一条高效、无缝的通信连接,同时使整个驱动程序框架拥有非常好的可扩展性。     

基于Ubuntu的字符型设备驱动程序开发实现

随着信息社会进入物联网时代,所有设备都需要通过开发应用程序以及驱动让计算机系统识别并使用,从而促进基于操作系统的底层驱动程序的开发工作。介绍Ubuntu16.04系统内核下开发底层设备驱动程序的过程,以Ubuntu系统内核为基础构建源码树、驱动模块编译、加载和卸载。分析Ubuntu系统下字符型设备驱动程序的设计方式,最后通过Ubuntu系统验证字符型设备驱动程序成功运行。     

基于QNX的PC104总线设备驱动模块的开发

QNX作为最优秀的嵌入式实时操作系统之一,已被应用于诸如医疗仪器、电网通信以及航空航天等任务关键型领域。在掌握QNX微内核结构和消息传递机制的基础上,论述了QNX下资源管理器的原理以及资源管理器与设备驱动程序的关系,具体分析了PC104总线设备驱动程序编写规范和步骤。实现了QNX下应用程序对硬件访问的无关性,大大增强了系统安全性以及移植性等。