What Do Compilers Produce? Pure Machine Code Compilers May Generate Code for a Particular Machine, Not Assuming Any Operating System Or Library Routines
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Chapter 1 Introduction to Computers, Programs, and Java
Chapter 1 Introduction to Computers, Programs, and Java 1.1 Introduction • The central theme of this book is to learn how to solve problems by writing a program . • This book teaches you how to create programs by using the Java programming languages . • Java is the Internet program language • Why Java? The answer is that Java enables user to deploy applications on the Internet for servers , desktop computers , and small hand-held devices . 1.2 What is a Computer? • A computer is an electronic device that stores and processes data. • A computer includes both hardware and software. o Hardware is the physical aspect of the computer that can be seen. o Software is the invisible instructions that control the hardware and make it work. • Computer programming consists of writing instructions for computers to perform. • A computer consists of the following hardware components o CPU (Central Processing Unit) o Memory (Main memory) o Storage Devices (hard disk, floppy disk, CDs) o Input/Output devices (monitor, printer, keyboard, mouse) o Communication devices (Modem, NIC (Network Interface Card)). Bus Storage Communication Input Output Memory CPU Devices Devices Devices Devices e.g., Disk, CD, e.g., Modem, e.g., Keyboard, e.g., Monitor, and Tape and NIC Mouse Printer FIGURE 1.1 A computer consists of a CPU, memory, Hard disk, floppy disk, monitor, printer, and communication devices. CMPS161 Class Notes (Chap 01) Page 1 / 15 Kuo-pao Yang 1.2.1 Central Processing Unit (CPU) • The central processing unit (CPU) is the brain of a computer. • It retrieves instructions from memory and executes them. -
Binary and Hexadecimal
Binary and Hexadecimal Binary and Hexadecimal Introduction This document introduces the binary (base two) and hexadecimal (base sixteen) number systems as a foundation for systems programming tasks and debugging. In this document, if the base of a number might be ambiguous, we use a base subscript to indicate the base of the value. For example: 45310 is a base ten (decimal) value 11012 is a base two (binary) value 821716 is a base sixteen (hexadecimal) value Why do we need binary? The binary number system (also called the base two number system) is the native language of digital computers. No matter how elegantly or naturally we might interact with today’s computers, phones, and other smart devices, all instructions and data are ultimately stored and manipulated in the computer as binary digits (also called bits, where a bit is either a 0 or a 1). CPUs (central processing units) and storage devices can only deal with information in this form. In a computer system, absolutely everything is represented as binary values, whether it’s a program you’re running, an image you’re viewing, a video you’re watching, or a document you’re writing. Everything, including text and images, is represented in binary. In the “old days,” before computer programming languages were available, programmers had to use sequences of binary digits to communicate directly with the computer. Today’s high level languages attempt to shield us from having to deal with binary at all. However, there are a few reasons why it’s important for programmers to understand the binary number system: 1. -
Language Translators
Student Notes Theory LANGUAGE TRANSLATORS A. HIGH AND LOW LEVEL LANGUAGES Programming languages Low – Level Languages High-Level Languages Example: Assembly Language Example: Pascal, Basic, Java Characteristics of LOW Level Languages: They are machine oriented : an assembly language program written for one machine will not work on any other type of machine unless they happen to use the same processor chip. Each assembly language statement generally translates into one machine code instruction, therefore the program becomes long and time-consuming to create. Example: 10100101 01110001 LDA &71 01101001 00000001 ADD #&01 10000101 01110001 STA &71 Characteristics of HIGH Level Languages: They are not machine oriented: in theory they are portable , meaning that a program written for one machine will run on any other machine for which the appropriate compiler or interpreter is available. They are problem oriented: most high level languages have structures and facilities appropriate to a particular use or type of problem. For example, FORTRAN was developed for use in solving mathematical problems. Some languages, such as PASCAL were developed as general-purpose languages. Statements in high-level languages usually resemble English sentences or mathematical expressions and these languages tend to be easier to learn and understand than assembly language. Each statement in a high level language will be translated into several machine code instructions. Example: number:= number + 1; 10100101 01110001 01101001 00000001 10000101 01110001 B. GENERATIONS OF PROGRAMMING LANGUAGES 4th generation 4GLs 3rd generation High Level Languages 2nd generation Low-level Languages 1st generation Machine Code Page 1 of 5 K Aquilina Student Notes Theory 1. MACHINE LANGUAGE – 1ST GENERATION In the early days of computer programming all programs had to be written in machine code. -
Exposing Native Device Apis to Web Apps
Exposing Native Device APIs to Web Apps Arno Puder Nikolai Tillmann Michał Moskal San Francisco State University Microsoft Research Microsoft Research Computer Science One Microsoft Way One Microsoft Way Department Redmond, WA 98052 Redmond, WA 98052 1600 Holloway Avenue [email protected] [email protected] San Francisco, CA 94132 [email protected] ABSTRACT language of the respective platform, HTML5 technologies A recent survey among developers revealed that half plan to gain traction for the development of mobile apps [12, 4]. use HTML5 for mobile apps in the future. An earlier survey A recent survey among developers revealed that more than showed that access to native device APIs is the biggest short- half (52%) are using HTML5 technologies for developing mo- coming of HTML5 compared to native apps. Several dif- bile apps [22]. HTML5 technologies enable the reuse of the ferent approaches exist to overcome this limitation, among presentation layer and high-level logic across multiple plat- them cross-compilation and packaging the HTML5 as a na- forms. However, an earlier survey [21] on cross-platform tive app. In this paper we propose a novel approach by using developer tools revealed that access to native device APIs a device-local service that runs on the smartphone and that is the biggest shortcoming of HTML5 compared to native acts as a gateway to the native layer for HTML5-based apps apps. Several different approaches exist to overcome this running inside the standard browser. WebSockets are used limitation. Besides the development of native apps for spe- for bi-directional communication between the web apps and cific platforms, popular approaches include cross-platform the device-local service. -
Cloud Native Trail Map 2
1. CONTAINERIZATION • Commonly done with Docker containers • Any size application and dependencies (even PDP-11 code running on an emulator) can be containerized • Over time, you should aspire towards splitting suitable applications and writing future functionality as microservices CLOUD NATIVE TRAIL MAP 2. CI/CD • Setup Continuous Integration/Continuous Delivery (CI/CD) so The Cloud Native Landscape l.cncf.io that changes to your source code automatically result in a new has a large number of options. This Cloud container being built, tested, and deployed to staging and Native Trail Map is a recommended process eventually, perhaps, to production for leveraging open source, cloud native • Setup automated rollouts, roll backs and testing technologies. At each step, you can choose • Argo is a set of Kubernetes-native tools for a vendor-supported offering or do it yourself, deploying and running jobs, applications, and everything after step #3 is optional workflows, and events using GitOps based on your circumstances. 3. ORCHESTRATION & paradigms such as continuous and progressive delivery and MLops CNCF Incubating APPLICATION DEFINITION HELP ALONG THE WAY • Kubernetes is the market-leading orchestration solution • You should select a Certified Kubernetes Distribution, 4. OBSERVABILITY & ANALYSIS Hosted Platform, or Installer: cncf.io/ck A. Training and Certification • Helm Charts help you define, install, and upgrade • Pick solutions for monitoring, logging and tracing Consider training offerings from CNCF even the most complex Kubernetes application • Consider CNCF projects Prometheus for monitoring, and then take the exam to become a Fluentd for logging and Jaeger for Tracing Certified Kubernetes Administrator or a • For tracing, look for an OpenTracing-compatible Certified Kubernetes Application Developer implementation like Jaeger cncf.io/training CNCF Graduated CNCF Graduated B. -
Complete Code Generation from UML State Machine
Complete Code Generation from UML State Machine Van Cam Pham, Ansgar Radermacher, Sebastien´ Gerard´ and Shuai Li CEA, LIST, Laboratory of Model Driven Engineering for Embedded Systems, P.C. 174, Gif-sur-Yvette, 91191, France Keywords: UML State Machine, Code Generation, Semantics-conformance, Efficiency, Events, C++. Abstract: An event-driven architecture is a useful way to design and implement complex systems. The UML State Machine and its visualizations are a powerful means to the modeling of the logical behavior of such an archi- tecture. In Model Driven Engineering, executable code can be automatically generated from state machines. However, existing generation approaches and tools from UML State Machines are still limited to simple cases, especially when considering concurrency and pseudo states such as history, junction, and event types. This paper provides a pattern and tool for complete and efficient code generation approach from UML State Ma- chine. It extends IF-ELSE-SWITCH constructions of programming languages with concurrency support. The code generated with our approach has been executed with a set of state-machine examples that are part of a test-suite described in the recent OMG standard Precise Semantics Of State Machine. The traced execution results comply with the standard and are a good hint that the execution is semantically correct. The generated code is also efficient: it supports multi-thread-based concurrency, and the (static and dynamic) efficiency of generated code is improved compared to considered approaches. 1 INTRODUCTION Completeness: Existing tools and approaches mainly focus on the sequential aspect while the concurrency The UML State Machine (USM) (Specification and of state machines is limitedly supported. -
Chapter 1 Introduction to Computers, Programs, and Java
Chapter 1 Introduction to Computers, Programs, and Java 1.1 Introduction • Java is the Internet program language • Why Java? The answer is that Java enables user to deploy applications on the Internet for servers, desktop computers, and small hand-held devices. 1.2 What is a Computer? • A computer is an electronic device that stores and processes data. • A computer includes both hardware and software. o Hardware is the physical aspect of the computer that can be seen. o Software is the invisible instructions that control the hardware and make it work. • Programming consists of writing instructions for computers to perform. • A computer consists of the following hardware components o CPU (Central Processing Unit) o Memory (Main memory) o Storage Devices (hard disk, floppy disk, CDs) o Input/Output devices (monitor, printer, keyboard, mouse) o Communication devices (Modem, NIC (Network Interface Card)). Memory Disk, CD, and Storage Input Keyboard, Tape Devices Devices Mouse CPU Modem, and Communication Output Monitor, NIC Devices Devices Printer FIGURE 1.1 A computer consists of a CPU, memory, Hard disk, floppy disk, monitor, printer, and communication devices. 1.2.1 Central Processing Unit (CPU) • The central processing unit (CPU) is the brain of a computer. • It retrieves instructions from memory and executes them. • The CPU usually has two components: a control Unit and Arithmetic/Logic Unit. • The control unit coordinates the actions of the other components. • The ALU unit performs numeric operations (+ - / *) and logical operations (comparison). • The CPU speed is measured by clock speed in megahertz (MHz), with 1 megahertz equaling 1 million pulses per second. -
Rockbox User Manual
The Rockbox Manual for Ipod Classic rockbox.org December 27, 2020 2 Rockbox https://www.rockbox.org/ Open Source Jukebox Firmware Rockbox and this manual is the collaborative effort of the Rockbox team and its contributors. See the appendix for a complete list of contributors. c 2003–2020 The Rockbox Team and its contributors, c 2004 Christi Alice Scarborough, c 2003 José Maria Garcia-Valdecasas Bernal & Peter Schlenker. Version 3.15p10. Built using pdfLATEX. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sec- tions, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”. The Rockbox manual (version 3.15p10) Ipod Classic Contents 3 Contents 1. Introduction 12 1.1. Welcome..................................... 12 1.2. Getting more help............................... 12 1.3. Naming conventions and marks........................ 13 2. Installation 14 2.1. Before Starting................................. 14 2.2. Installing Rockbox............................... 15 2.2.1. Automated Installation........................ 15 2.2.2. Manual Installation.......................... 17 2.2.3. Finishing the install.......................... 19 2.2.4. Enabling Speech Support (optional)................. 19 2.3. Running Rockbox................................ 19 2.4. Updating Rockbox............................... 19 2.5. Uninstalling Rockbox............................. 20 2.5.1. Automatic Uninstallation....................... 20 2.5.2. Manual Uninstallation......................... 20 2.6. Troubleshooting................................. 20 3. Quick Start 21 3.1. Basic Overview................................. 21 3.1.1. The player’s controls.......................... 21 3.1.2. Turning the player on and off.................... -
Defeating Kernel Native API Hookers by Direct Kiservicetable Restoration
Defeating Kernel Native API Hookers by Direct KiServiceTable Restoration Tan Chew Keong Vice-President SIG2 www.security.org.sg IT Security... the Gathering. By enthusiasts for enthusiasts! Outline • User-space API calls and Native APIs • Redirecting the execution path of Native APIs • Locating and restoring the KiServiceTable • Defeating Native API hooking rootkits and security tools. IT Security... the Gathering. By enthusiasts for enthusiasts! User-space API calls • User-space Win32 applications requests for system services by calling APIs exported by various DLLs. • For example, to write to an open file, pipe or device, the WriteFile API, exported by kernel32.dll is used. IT Security... the Gathering. By enthusiasts for enthusiasts! User-space API calls • WriteFile API will in turn call the native API NtWriteFile/ZwWriteFile that is exported by ntdll.dll • In ntdll.dll, both NtWriteFile and ZwWriteFile points to the same code. • Actual work is actually performed in kernel- space, hence NtWriteFile/ZwWritefile in ntdll.dll contains only minimal code to transit into kernel code using software interrupt INT 0x2E IT Security... the Gathering. By enthusiasts for enthusiasts! User-space API calls • In Win2k, NtWriteFile/ZwWriteFile in ntdll.dll disassembles to MOV EAX, 0EDh LEA EDX, DWORD PTR SS:[ESP+4] INT 2E RETN 24 • 0xED is the system service number that will be used to index into the KiServiceTable to locate the kernel function that handles the call. IT Security... the Gathering. By enthusiasts for enthusiasts! User-space API calls Application WriteFile() kernel32.dll Nt/ZwWriteFile() mov eax, system service num ntdll.dll lea edx, pointer to parameters int 0x2E ntoskrnl.exe NtWriteFile() IT Security.. -
X86 Assembly Language Reference Manual
x86 Assembly Language Reference Manual Part No: 817–5477–11 March 2010 Copyright ©2010 Oracle and/or its affiliates. All rights reserved. This software and related documentation are provided under a license agreement containing restrictions on use and disclosure and are protected by intellectual property laws. Except as expressly permitted in your license agreement or allowed by law, you may not use, copy, reproduce, translate, broadcast, modify, license, transmit, distribute, exhibit, perform, publish, or display any part, in any form, or by any means. Reverse engineering, disassembly, or decompilation of this software, unless required by law for interoperability, is prohibited. The information contained herein is subject to change without notice and is not warranted to be error-free. If you find any errors, please report them to us in writing. If this is software or related software documentation that is delivered to the U.S. Government or anyone licensing it on behalf of the U.S. Government, the following notice is applicable: U.S. GOVERNMENT RIGHTS Programs, software, databases, and related documentation and technical data delivered to U.S. Government customers are “commercial computer software” or “commercial technical data” pursuant to the applicable Federal Acquisition Regulation and agency-specific supplemental regulations. As such, the use, duplication, disclosure, modification, and adaptation shall be subject to the restrictions and license terms setforth in the applicable Government contract, and, to the extent applicable by the terms of the Government contract, the additional rights set forth in FAR 52.227-19, Commercial Computer Software License (December 2007). Oracle USA, Inc., 500 Oracle Parkway, Redwood City, CA 94065. -
Design of the RISC-V Instruction Set Architecture
Design of the RISC-V Instruction Set Architecture Andrew Waterman Electrical Engineering and Computer Sciences University of California at Berkeley Technical Report No. UCB/EECS-2016-1 http://www.eecs.berkeley.edu/Pubs/TechRpts/2016/EECS-2016-1.html January 3, 2016 Copyright © 2016, by the author(s). All rights reserved. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission. Design of the RISC-V Instruction Set Architecture by Andrew Shell Waterman A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the Graduate Division of the University of California, Berkeley Committee in charge: Professor David Patterson, Chair Professor Krste Asanovi´c Associate Professor Per-Olof Persson Spring 2016 Design of the RISC-V Instruction Set Architecture Copyright 2016 by Andrew Shell Waterman 1 Abstract Design of the RISC-V Instruction Set Architecture by Andrew Shell Waterman Doctor of Philosophy in Computer Science University of California, Berkeley Professor David Patterson, Chair The hardware-software interface, embodied in the instruction set architecture (ISA), is arguably the most important interface in a computer system. Yet, in contrast to nearly all other interfaces in a modern computer system, all commercially popular ISAs are proprietary. -
What Is a Computer Program? 1 High-Level Vs Low-Level Languages
What Is A Computer Program? Scientific Computing Fall, 2019 Paul Gribble 1 High-level vs low-level languages1 2 Interpreted vs compiled languages3 What is a computer program? What is code? What is a computer language? A computer program is simply a series of instructions that the computer executes, one after the other. An instruction is a single command. A program is a series of instructions. Code is another way of referring to a single instruction or a series of instructions (a program). 1 High-level vs low-level languages The CPU (central processing unit) chip(s) that sit on the motherboard of your computer is the piece of hardware that actually executes instructions. A CPU only understands a relatively low-level language called machine code. Often machine code is generated automatically by translating code written in assembly language, which is a low-level programming language that has a relatively direcy relationship to machine code (but is more readable by a human). A utility program called an assembler is what translates assembly language code into machine code. In this course we will be learning how to program in MATLAB, which is a high-level programming language. The “high-level” refers to the fact that the language has a strong abstraction from the details of the computer (the details of the machine code). A “strong abstraction” means that one can operate using high-level instructions without having to worry about the low-level details of carrying out those instructions. An analogy is motor skill learning. A high-level language for human action might be drive your car to the grocery store and buy apples.