How Xlib Is Implemented (And What We're Doing About It)

Total Page：16

File Type：pdf, Size：1020Kb

How Xlib Is Implemented (And What We're Doing About It) Jamey Sharp Computer Science Department Portland State University Portland, OR USA 97207-0751 [email protected] http://xcb.freedesktop.org X Window System Architecture Client Client Client Server Toolkit I18N Protocol Utility Protocol Xlib Transport Transport Xlib Architecture Transport layer: conveys requests and re- sponses between client and server Protocol layer: constructs requests and un- packs replies Utilities layer: does everything else utility cut buffers gc image icccm i18n xlc resource db cms xkb region xom xim core protocol events protocol transport Some Xlib Issues Xlib Component Sizes Large size Inflexible code Unpredictable transport behavior core protocol cms Excessive la- xkb xom tency xlc Confusing xim other thread support Starting Over: XCB Simpler, smaller implementation Focus on transport, protocol New domain-specific language for X protocol description provides flexibility maintainability Xlib XCB 0 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 Kilobytes of code, compiled for Intel x86 Porting Xlib to XCB Goal: provide a migration path for Xlib- based applications and libraries First try: XCL Idea: re-implement Xlib's API from scratch using XCB Problem: Xlib's API is huge Current approach: start migration at bottom Replace transport and locking with XCB Prototype implemented in a few days! Slowly migrate protocol layer to XCB Results X Test Suite and real workloads confirm substantial correctness; some bugs remain Locking and transport are simpler and smaller; protocol port not yet complete Xlib extensions protocol Xlib/ XCB transport locking 0 25 50 75 100 125 Kilobytes of code, compiled for Intel x86 Any changes in performance are impercep- tible Other Xlib Projects Xlib Component Sizes Redesigning other Xlib compo- nents transport cms core protocol cms xkb xkb xom xom/xlc/xim xlc xim other Conclusion Installed size of X client libraries are re- duced significantly Clarity, maintainability, and extensibility are improved as well Acknowledgements Keith Packard helped us comprehend Xlib and the X Window System. Prof. Bart Massey guides the design and implementation of XCB. Jim Gettys' continued support of this effort is greatly appreciated. Portland State University students Sheridan Mahoney and Mick Thomure provided valuable feedback on the current paper. USENIX Availability XCB: http://xcb.freedesktop.org/ Xlib: http://freedesktop.org/Software/X11.

Copy Link

Recommended publications

R&S®BBA100 Broadband Amplifier Open
R&S®BBA100 Broadband Amplifier Open Source Acknowledgment 5353.8300.00 – 01 /RL/1/EN 01.00 / Broadcasting 3575.4620.02 M: - T - PAD Open Source Acknowledgment R&S BBA100 Introduction Contents 1 Introduction ......................................................................................... 3 1.1 Disclaimer ..................................................................................................................... 3 1.2 How to obtain the source code .................................................................................. 3 2 Software packages ............................................................................. 4 3 Verbatim license texts ........................................................................ 7 3.1 Apache License 2.0 ..................................................................................................... 7 3.2 GNU Library General Public License, Version 2.0 (LGPL 2.0) ..............................10 3.3 Boost Software License ............................................................................................18 3.4 GNU General Public License, Version 2.0 (GPL 2.0) ..............................................18 3.5 GNU Lesser General Public License, Version 2.1 (LGPL 2.1) ...............................24 3.6 Mozilla Public License, Version 1.1 (MPL 1.1) ........................................................32 3.7 MIT ...............................................................................................................................40 3.8 JDOM License
[Show full text]
Release Notes for X11R6.8.2 the X.Orgfoundation the Xfree86 Project, Inc
Release Notes for X11R6.8.2 The X.OrgFoundation The XFree86 Project, Inc. 9February 2005 Abstract These release notes contains information about features and their status in the X.Org Foundation X11R6.8.2 release. It is based on the XFree86 4.4RC2 RELNOTES docu- ment published by The XFree86™ Project, Inc. Thereare significant updates and dif- ferences in the X.Orgrelease as noted below. 1. Introduction to the X11R6.8.2 Release The release numbering is based on the original MIT X numbering system. X11refers to the ver- sion of the network protocol that the X Window system is based on: Version 11was first released in 1988 and has been stable for 15 years, with only upwardcompatible additions to the coreX protocol, a recordofstability envied in computing. Formal releases of X started with X version 9 from MIT;the first commercial X products werebased on X version 10. The MIT X Consortium and its successors, the X Consortium, the Open Group X Project Team, and the X.OrgGroup released versions X11R3 through X11R6.6, beforethe founding of the X.OrgFoundation. Therewill be futuremaintenance releases in the X11R6.8.x series. However,efforts arewell underway to split the X distribution into its modular components to allow for easier maintenance and independent updates. We expect a transitional period while both X11R6.8 releases arebeing fielded and the modular release completed and deployed while both will be available as different consumers of X technology have different constraints on deployment. Wehave not yet decided how the modular X releases will be numbered. We encourage you to submit bug fixes and enhancements to bugzilla.freedesktop.orgusing the xorgproduct, and discussions on this server take place on <[email protected]>.
[Show full text]
THINC: a Virtual and Remote Display Architecture for Desktop Computing and Mobile Devices
THINC: A Virtual and Remote Display Architecture for Desktop Computing and Mobile Devices Ricardo A. Baratto Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2011 c 2011 Ricardo A. Baratto This work may be used in accordance with Creative Commons, Attribution-NonCommercial-NoDerivs License. For more information about that license, see http://creativecommons.org/licenses/by-nc-nd/3.0/. For other uses, please contact the author. ABSTRACT THINC: A Virtual and Remote Display Architecture for Desktop Computing and Mobile Devices Ricardo A. Baratto THINC is a new virtual and remote display architecture for desktop computing. It has been designed to address the limitations and performance shortcomings of existing remote display technology, and to provide a building block around which novel desktop architectures can be built. THINC is architected around the notion of a virtual display device driver, a software-only component that behaves like a traditional device driver, but instead of managing specific hardware, enables desktop input and output to be intercepted, manipulated, and redirected at will. On top of this architecture, THINC introduces a simple, low-level, device-independent representation of display changes, and a number of novel optimizations and techniques to perform efficient interception and redirection of display output. This dissertation presents the design and implementation of THINC. It also intro- duces a number of novel systems which build upon THINC's architecture to provide new and improved desktop computing services. The contributions of this dissertation are as follows: • A high performance remote display system for LAN and WAN environments.
[Show full text]
Porting a Window Manager from Xlib to XCB
Porting a Window Manager from Xlib to XCB Arnaud Fontaine (08090091) 16 May 2008 Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version pub- lished by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". Contents List of ﬁgures i List of listings ii Introduction 1 1 Backgrounds and Motivations 2 2 X Window System (X11) 6 2.1 Introduction . .6 2.2 History . .6 2.3 X Window Protocol . .7 2.3.1 Introduction . .7 2.3.2 Protocol overview . .8 2.3.3 Identiﬁers of resources . 10 2.3.4 Atoms . 10 2.3.5 Windows . 12 2.3.6 Pixmaps . 14 2.3.7 Events . 14 2.3.8 Keyboard and pointer . 15 2.3.9 Extensions . 17 2.4 X protocol client libraries . 18 2.4.1 Xlib . 18 2.4.1.1 Introduction . 18 2.4.1.2 Data types and functions . 18 2.4.1.3 Pros . 19 2.4.1.4 Cons . 19 2.4.1.5 Example . 20 2.4.2 XCB . 20 2.4.2.1 Introduction . 20 2.4.2.2 Data types and functions . 21 2.4.2.3 xcb-util library . 22 2.4.2.4 Pros . 22 2.4.2.5 Cons . 23 2.4.2.6 Example . 23 2.4.3 Xlib/XCB round-trip performance comparison .
[Show full text]
X Meets Z: Verifying Correctness in the Presence of POSIX Threads
X Meets Z: Verifying Correctness In The Presence Of POSIX Threads Bart Massey Robert Bauer Computer Science Department Rational Software Corporation Portland State University 1920 Amberglen Pkwy, Suite 200 Portland, Oregon USA 97207–0751 Beaverton, Oregon USA 97006 [email protected] [email protected] Abstract and guide the development of resulting code. While this approach is not a panacea, it typically does dramatically The engineering of freely-available UNIX software nor- reduce the likelihood of defects and increase confidence mally utilizes an informal analysis and design process in the developed system. A more surprising finding of coupled with extensive user testing. While this approach most of these case studies, confirmed by the authors’ ex- is often appropriate, there are situations for which it pro- perience in teaching formal methods to industrial prac- duces less-than-stellar results. titioners, is that Z-like lightweight formal methods are quite accessible to reasonably experienced software en- A case study is given of such a situation that arose dur- gineers. In fact, in many studies, the savings in time and ing the design and implementation of a thread-safe li- effort due to reduced defect rates has exceeded the extra brary for interaction with the X Window System. XCB cost of judiciously-applied formal analysis. is a C binding library for the X protocol designed to work transparently with either single-threaded or multi- Thus, using the Z notation to construct a lightweight threaded clients. Managing XCB client thread access to problem model can enable the construction of an algo- the X server while honoring the constraints of both XCB rithm for controlling client thread access to the server and the X server is thus a delicate matter.
[Show full text]
Security at Extreme Scales
SECURITY AT EXTREME SCALES Recommended Citation Eric Grosse, "SECURITY AT EXTREME SCALES", NAPSNet Special Reports, May 30, 2019, https://nautilus.org/napsnet/napsnet-special-reports/security-at-extreme-scales/ ERIC GROSSE MAY 30, 2019 I. INTRODUCTION 1 In this paper, Eric Grosse argues: “Much of the security progress over the past decade has been at large-scale, finding and patching vulnerabilities in widely used applications or defending networks of millions of machines containing high-value data. The lessons there may help military systems, but for the very highest security needs such as NC3, we ought to return to basics and harden small-scale systems. And we ought to do it as a joint effort, even between adversaries.” Eric Grosse was Google's VP Security & Privacy Engineering. Before Google, Eric was a Research Director and Fellow at Bell Labs. He has a Ph.D. in Computer Science from Stanford. Acknowledgments: The workshop was funded by the John D. and Catherine T. MacArthur Foundation. This report is published simultaneously here by Technology for Global Security and here by Nautilus Institute and is published under a 4.0 International Creative Commons License the terms of which are found here. The views expressed in this report do not necessarily reflect the official policy or position of the Nautilus Institute. Readers should note that Nautilus seeks a diversity of views and opinions on significant topics in order to identify common ground. A podcast with Eric Grosse, Peter Hayes, and Philip Reiner on NC3 and security at extreme scales is found here. The views expressed in this report do not necessarily reflect the official policy or position of the Nautilus Institute.
[Show full text]
X Window System Network Performance
X Window System Network Performance Keith Packard Cambridge Research Laboratory, HP Labs, HP [email protected] James Gettys Cambridge Research Laboratory, HP Labs, HP [email protected] Abstract havior (or on a local machine, context switches between the application and the X server). Performance was an important issue in the develop- One of the authors used the network visualization tool ment of X from the initial protocol design and contin- when analyzing the design of HTTP/1.1 [NGBS 97]. ues to be important in modern application and extension The methodology and tools used in that analysis in- development. That X is network transparent allows us volved passive packet level monitoring of traffic which to analyze the behavior of X from a perspective seldom allowed precise real-world measurements and compar- possible in most systems. We passively monitor network isons. The work described in this paper combines this packet flow to measure X application and server perfor- passive packet capture methodology with additional X mance. The network simulation environment, the data protocol specific analysis and visualization. Our experi- capture tool and data analysis tools will be presented. ence with this combination of the general technique with Data from this analysis are used to show the performance X specific additions was very positive and we believe impact of the Render extension, the limitations of the provides a powerful tool that could be used in the analy- LBX extension and help identify specific application and sis of other widely used protocols. toolkit performance problems. We believe this analysis With measurement tools in hand, we set about char- technique can be usefully applied to other network pro- acterizing the performance of a significant selection of tocols.
[Show full text]
Xlib − C Language X Interface Xwindowsystem Standard Xversion 11, Release 7 Libx11 1.3.2
Xlib − C Language X Interface XWindowSystem Standard XVersion 11, Release 7 libX11 1.3.2 James Gettys Cambridge Research Laboratory Digital Equipment Corporation Robert W.Scheiﬂer Laboratory for Computer Science Massachusetts Institute of Technology with contributions from Chuck Adams, Tektronix, Inc. Vania Joloboff, Open Software Foundation Hideki Hiura, Sun Microsystems, Inc. Bill McMahon, Hewlett-Packard Company Ron Newman, Massachusetts Institute of Technology Al Tabayoyon, Tektronix, Inc. Glenn Widener,Tektronix, Inc. Shigeru Yamada, Fujitsu OSSI The X WindowSystem is a trademark of The Open Group. TekHVC is a trademark of Tektronix, Inc. Copyright © 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1994, 1996, 2002 The Open Group Permission is hereby granted, free of charge, to anyperson obtaining a copyofthis software and associated documenta- tion 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 Soft- ware. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOTLIMITED TOTHE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTIC- ULAR PURPOSE AND NONINFRINGEMENT.INNOEVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,WHETHER IN AN ACTION OF CONTRACT,TORTOROTH- ERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
[Show full text]
Release Notes for X11R7.5 the X.Org Foundation 1
Release Notes for X11R7.5 The X.Org Foundation 1 October 2009 These release notes contains information about features and their status in the X.Org Foundation X11R7.5 release. Table of Contents Introduction to the X11R7.5 Release.................................................................................3 Summary of new features in X11R7.5...............................................................................3 Overview of X11R7.5............................................................................................................4 Details of X11R7.5 components..........................................................................................5 Build changes and issues..................................................................................................10 Miscellaneous......................................................................................................................11 Deprecated components and removal plans.................................................................12 Attributions/Acknowledgements/Credits......................................................................13 Introduction to the X11R7.5 Release This release is the sixth modular release of the X Window System. The next full release will be X11R7.6 and is expected in 2010. Unlike X11R1 through X11R6.9, X11R7.x releases are not built from one monolithic source tree, but many individual modules. These modules are distributed as individ- ual source code releases, and each one is released when it is ready, instead
[Show full text]
Proceedings of the FREENIX Track: 2002 USENIX Annual Technical Conference
USENIX Association Proceedings of the FREENIX Track: 2002 USENIX Annual Technical Conference Monterey, California, USA June 10-15, 2002 THE ADVANCED COMPUTING SYSTEMS ASSOCIATION © 2002 by The USENIX Association All Rights Reserved For more information about the USENIX Association: Phone: 1 510 528 8649 FAX: 1 510 548 5738 Email: [email protected] WWW: http://www.usenix.org Rights to individual papers remain with the author or the author's employer. Permission is granted for noncommercial reproduction of the work for educational or research purposes. This copyright notice must be included in the reproduced paper. USENIX acknowledges all trademarks herein. XCL : An Xlib Compatibility Layer For XCB Jamey Sharp Bart Massey Computer Science Department Portland State University Portland, Oregon USA 97207–0751 fjamey,[email protected] Abstract 1 The X Window System The X Window System [SG86] is the de facto standard technology for UNIX applications wishing to provide a graphical user interface. The power and success of the X model is due in no small measure to its separation of The X Window System has provided the standard graph- hardware control from application logic with a stable, ical user interface for UNIX systems for more than 15 published client-server network protocol. In this model, years. One result is a large installed base of X applica- the hardware controller is considered the server, and in- tions written in C and C++. In almost all cases, these dividual applications and other components of a com- programs rely on the Xlib library to manage their inter- plete desktop environment are clients.
[Show full text]
Xlib − C Language X Interface Xconsortium Standard Xversion 11, Release 6.7 DRAFT
Xlib − C Language X Interface XConsortium Standard XVersion 11, Release 6.7 DRAFT James Gettys Cambridge Research Laboratory Digital Equipment Corporation Robert W.Scheiﬂer Laboratory for Computer Science Massachusetts Institute of Technology with contributions from Chuck Adams, Tektronix, Inc. Vania Joloboff, Open Software Foundation Hideki Hiura, Sun Microsystems, Inc. Bill McMahon, Hewlett-Packard Company Ron Newman, Massachusetts Institute of Technology Al Tabayoyon, Tektronix, Inc. Glenn Widener,Tektronix, Inc. Shigeru Yamada, Fujitsu OSSI The X WindowSystem is a trademark of The Open Group. TekHVC is a trademark of Tektronix, Inc. Copyright © 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1994, 1996, 2002 The Open Group Permission is hereby granted, free of charge, to anyperson obtaining a copyofthis software and associated documenta- tion 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 Soft- ware. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOTLIMITED TOTHE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTIC- ULAR PURPOSE AND NONINFRINGEMENT.INNOEVENT SHALL THE X CONSORTIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,WHETHER IN AN ACTION OF CONTRACT,TORTOROTH- ERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of The Open Group shall not be used in advertising or otherwise to pro- mote the sale, use or other dealings in this Software without prior written authorization from The Open Group.
[Show full text]
Upgrading and Performance Analysis of Thin Clients in Server Based Scientific Computing
Institutionen för Systemteknik Department of Electrical Engineering Examensarbete Upgrading and Performance Analysis of Thin Clients in Server Based Scientific Computing Master Thesis in ISY Communication System By Rizwan Azhar LiTH-ISY-EX - - 11/4388 - - SE Linköping 2011 Department of Electrical Engineering Linköpings Tekniska Högskola Linköpings universitet Linköpings universitet SE-581 83 Linköping, Sweden 581 83 Linköping, Sweden Upgrading and Performance Analysis of Thin Clients in Server Based Scientific Computing Master Thesis in ISY Communication System at Linköping Institute of Technology By Rizwan Azhar LiTH-ISY-EX - - 11/4388 - - SE Examiner: Dr. Lasse Alfredsson Advisor: Dr. Alexandr Malusek Supervisor: Dr. Peter Lundberg Presentation Date Department and Division 04-02-2011 Department of Electrical Engineering Publishing Date (Electronic version) Language Type of Publication ISBN (Licentiate thesis) X English Licentiate thesis ISRN: Other (specify below) X Degree thesis LiTH-ISY-EX - - 11/4388 - - SE Thesis C-level Thesis D-level Title of series (Licentiate thesis) 55 Report Number of Pages Other (specify below) Series number/ISSN (Licentiate thesis) URL, Electronic Version http://www.ep.liu.se Publication Title Upgrading and Performance Analysis of Thin Clients in Server Based Scientific Computing Author Rizwan Azhar Abstract Server Based Computing (SBC) technology allows applications to be deployed, managed, supported and executed on the server and not on the client; only the screen information is transmitted between the server and client. This architecture solves many fundamental problems with application deployment, technical support, data storage, hardware and software upgrades. This thesis is targeted at upgrading and evaluating performance of thin clients in scientific Server Based Computing (SBC). Performance of Linux based SBC was assessed via methods of both quantitative and qualitative research.
[Show full text]