Smartphone Operating System (Symbian Books)

Smartphone Operating SystemConcepts with Symbian OSA Tutorial GuideSmartphone OperatingSystem Concepts withSymbian OSA Tutorial GuideMichael J. JippingReviewed byAttila Vamos, Chris Notton, Freddie Gjertsen,Gema Gomez-Solano, Ian McDowall, Jason Parker,Jonathan Yu, Kostyantyn Lutsenko, Matthew O’Donnell,Phil Spencer, Rahul Singh, Ricky Junday, Roy Ben HayunHead of Symbian PressFreddie GjertsenManaging EditorSatu McNabbCopyright  2007Published bySymbian Software, Ltd.John Wiley & Sons Ltd, The Atrium, Southern Gate, Chichester,West Sussex PO19 8SQ, EnglandTelephone (+44) 1243 779777Email (for orders and customer service enquiries): cs-books@wiley.co.ukVisit our Home Page on www.wileyeurope.com or www.wiley.comAll Rights Reserved.

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Some content that appearsin print may not be available in electronic books.Anniversary Logo Design: Richard J. PacificoLibrary of Congress Cataloging-in-Publication DataJipping, Michael J.Smartphone operating system concepts with Symbian OS : a tutorial guide / Mike Jipping ; reviewedby Attila Vamos … [et al] ; head of Symbian Press, Freddie Gjertsen ; managing editor, Satu McNabb.p. cm.Includes index.ISBN 978-0-470-03449-1 (pbk.

: alk. paper)1. Cellular telephones – Computer programs. 2. Symbian OS (Computer file)3. Pocket computers – Computer programs. I. Title.TK6570.M6J56 2007621.3845 6 – dc222006102031British Library Cataloguing in Publication DataA catalogue record for this book is available from the British LibraryISBN 978-0-470-03449-1 (PB)Typeset in 10/12pt Optima by Laserwords Private Limited, Chennai, IndiaPrinted and bound in Great Britain by TJ International, Padstow, CornwallThis book is printed on acid-free paper responsibly manufactured from sustainable forestryin which at least two trees are planted for each one used for paper production.ContentsAuthor’s AcknowledgementsixSymbian Press AcknowledgementsxiIntroduction1 Introduction to Mobile Phone Systems1.11.21.31.4What Is an Operating System?History of Operating SystemsComputer Systems and their Operating SystemsSummaryxiii12711162 The Character of Operating Systems172.1 The Evolution of Operating Systems2.2 Computer Structures2.3 Different Platforms2.4 SummaryExercises1719394344viCONTENTS3 Kernel Structure3.1 How a Kernel Is Put Together3.2 System Calls and the Kernel3.3 Interrupt Implementation3.4 Completing the Kernel Design in Symbian OS3.5 SummaryExercises4 Processes and Threads4.1 An Overview of the Process Model4.2 Programming with Processes4.3 SummaryExercises5 Process Scheduling474753545658586162798787895.1 Basic Concepts5.2 Scheduling Strategies5.3 Scheduling in Linux5.4 Scheduling in a Microkernel Architecture5.5 Scheduling in Symbian OS5.6 SummaryExercises90941031041051061076 Process Concurrency and Synchronization1096.1 Concepts and Models for Concurrency6.2 Semaphores6.3 Locks, Monitors and Other Abstractions6.4 The Dining Philosophers: A Classic Problem6.5 An Example in Unix6.6 Concurrency in Symbian OS6.7 Interprocess Communication6.8 Managing Deadlocks6.9 SummaryExercises7 Memory Management7.17.27.37.47.5Introduction and BackgroundSwapping and PagingSystems Without Virtual MemorySegmentationMemory in Symbian OS110116118120123126128133134135137138145154156159CONTENTSvii7.6 Memory Use in Linux7.7 SummaryExercises1621631648 File Systems and Storage1678.1 Files and Directories8.2 Implementation of a File System8.3 File Systems on Mobile Phones8.4 Security8.5 SummaryExercises9 Input and Output9.1 I/O Components9.2 I/O Hardware Issues9.3 I/O Software Issues9.4 I/O in Symbian OS9.5 SummaryExercises10 Networks10.1 Opening a Closed Environment10.2 Extending Computers in a Connected Environment10.3 Connectivity in Symbian OS10.4 SummaryExercises11 Modeling Communications11.1 Communications Models11.2 Communications on Symbian OS11.3 Communications on Other Operating Systems11.4 SummaryExercises12 Telephony12.1 Modeling Telephony Services12.2 A Structural Overview12.3 Voice over IP Telephony12.4 SummaryExercises167175188189194194197198201204209213214215215217226227227229230237242245245247248250260262262viiiCONTENTS13 Messaging13.1 The Character of Messaging13.2 The Symbian OS Messaging Model13.3 Message Handling in Linux13.4 SummaryExercises14 Security14.1 Understanding Security Issues14.2 Authorization14.3 Authentication14.4 System Threats14.5 Security on Smartphones14.6 SummaryExercises15 Virtual Machines15.1 Basic Concepts15.2 The Java Virtual Machine and Symbian OS15.3 SummaryExercises263264275281283284285286287288291293296297299299305307307Appendix A Web Resources309References311Index313Author’s AcknowledgementsThere are many people whose patience and forbearance meant that thisbook could be written.

My family – my wife and three children – put upwith me long enough to enable me to complete it.There are many folks at Symbian who were instrumental in getting thisbook out. In particular, Satu McNabb and Freddie Gjertsen were key tothis book’s publication. I especially laud Satu’s patience with me.This book needed software to make it work. Kathleen Ludewig’s Informant software was key to parts of the laboratory section. In addition, thecreators of TaskSpy and SMan software contributed to Informant.Symbian Press AcknowledgementsSymbian Press wishes to thank the author, Mike Jipping, for all his hardwork, dedication and enthusiasm with this book and also all technicalreviewers within Symbian who contributed by sharing their expertise anddedicating their time – many thanks.IntroductionIt is amazing to realize how important operating systems are to computers.So it is that the study of operating systems is of great importance as part ofstudying computers.

Operating systems support access and innovation;they allow the complicated inner workings of hardware to be used withease. As computers are developing rapidly, so are operating systems.It is interesting to note that despite the change and evolution whichoperating systems undergo, they also remain constant. The underlyingconcepts of operating systems change much more slowly than the waysto adapt those concepts to new computer systems.

As an example, theidea of a file has been implemented on computers for many years andwill continue to be used for many years to come.This book is written as an introduction to operating systems, witha focus on mobile phones and, specifically, Symbian OS. There aremany textbooks that describe most aspects of operating systems, butmost bypass mobile phone operating systems. Symbian OS is a uniqueand comprehensive mobile phone operating system and any completeexamination of operating systems should include it.This book is targeted at junior or senior undergraduate students.

Inaddition to simply presenting and discussing operating system concepts,this book is accompanied by exercises that can be performed in thecontext of laboratory or experimental assignments. These assignmentsxivINTRODUCTIONcan be assigned and worked on in the classroom or a student’s owntime. Hands-on experience can be very important in cementing variousconcepts.The Contents of this Book• Chapters 1 to 3 provide an introduction to operating systems. Theyexplain the history of operating systems and how operating systemscame to be. They describe what an operating system is, how operatingsystems are designed and what their structure is.