DevEnvironment.md

Development Environment

Because NachOS need to be built under 32bit.

Install 32-bit libraries on 64-bit Ubuntu

• How to compile 32-bit program on 64-bit gcc in C and C++
• HowTo Compile a 32-bit Application Using gcc On the 64-bit Linux Version
• Ubuntu apt-get install ia32 for 32-bit on 64-bit

sudo apt-get install gcc-multilib g++-multilib

Test:

#include <stdio.h>

int main(){
    long z;
    printf("Long int size is %i bytes long!\n", sizeof(z));
    return 0;
}

$ gcc -m32 -o output32 hello.c
$ ./output32
Long int size is 4 bytes long!

$ gcc -m64 -o output64 hello.c
$ ./output64
Long int size is 8 bytes long!

Use 32bit image directly

...

Use Docker with 32bit image

Building

Build the clean version given by TA

bash build_clean_nachos.sh
# the outcome image will be nachos:0.0.1

Build the modified version in this github repository

bash build_modified_nachos.sh
# the outcome image will be nachos:latest and nachos:0.1 (default)

# it can also take an argument of a specific version
./build_modified_nachos.sh 0.1.1

Build only the specific subdirectory (Recommend, especially when you're just dealing with a specific Lab)

# build threads for example (use any subdirectory name under nachos-3.4/code/)
./build_subdir_nachos.sh threads
# the outcome image will be nachos_<subdir>:latest

Running

Running example

# Interactive
$ docker run -it nachos:0.0.1

# Interactive with mount local project
# (Run this in the root of this repository)
$ docker run -it -v $(pwd)/Nachos:/Nachos nachos:latest

# Run a single test
$ docker run nachos:latest nachos/nachos-3.4/code/threads/nachos
*** thread 0 looped 0 times
*** thread 1 looped 0 times
*** thread 0 looped 1 times
*** thread 1 looped 1 times
*** thread 0 looped 2 times
*** thread 1 looped 2 times
*** thread 0 looped 3 times
*** thread 1 looped 3 times
*** thread 0 looped 4 times
*** thread 1 looped 4 times
No threads ready or runnable, and no pending interrupts.
Assuming the program completed.
Machine halting!

Ticks: total 130, idle 0, system 130, user 0
Disk I/O: reads 0, writes 0
Console I/O: reads 0, writes 0
Paging: faults 0
Network I/O: packets received 0, sent 0

Cleaning up...

# Other ways to playing around
# Interactive concole test
$ docker run -it nachos nachos/nachos-3.4/code/userprog/nachos -c
# Step by step user program
& docker run -it nachos nachos/nachos-3.4/code/userprog/nachos -s -d a -x nachos/nachos-3.4/code/test/halt

GDB debugging

# Example of debugging threads/nachos built by `./build_subdir_nachos.sh threads`
$ docker run -it nachos_threads gdb nachos/nachos-3.4/code/threads/nachos
(gdb) run -d t -q 1

References

• maojui/nachOS
• nwtgck/nachos-build-dockerfile

Docker related

• docker for beginners
  • github
• Docker ENTRYPOINT & CMD: Dockerfile best practices
• Arguments and variables in Docker
• docker run
  • Mounting a Folder in a Docker Container
• docker build
  • docker docs - docker build -t
  • docker docs - Best practices for writing Dockerfiles
  • docker docs - Create a base image
  • docker arg
    • docker docs - Dockerfile reference - ARG
  • docker cache
    • Understanding the Docker Cache for Faster Builds
  • Multi-stage builds
    • docker docs - Use multi-stage builds
    • Youtube - Drastically reduce the size of your DOCKER images with MULTISTAGE builds
• docker alpine
  • The 3 Biggest Wins When Using Alpine as a Base Docker Image

Shell script related

• default-value syntax
  • Default shell variables value
  • How to write a bash script that takes optional input arguments?
    • somecommand ${1:-foo}
  • Assigning default values to shell variables with a single command in bash
  • {var:=default} vs {var:-default} - what is difference?
    • Positional or special parameters cannot be assigned using := way