pbot/modules/compiler_vm

Installation:

You will need to download qemu and set up a virtual machine containing a system
with a compiler and, optionally, sensible ulimits/fork-preventation/other security.

Then you will need to edit some of the following files and replace IP addresses
and paths where appropriate (some locations may not yet be documented).

Once the files have been configured and copied to the appropriate locations,
you will need to first start up the compiler_vm_server.pl script, and then 
connect to qemu's monitor and issue the 'savevm 1' command to save the virtual 
machine in this state.  Between compiles, this state will be loaded via 
'loadvm 1' in order to reset everything within the machine for a clean and working
environment for subsequent compiles.

Files:

(Read within each file for configuration instructions.)

- compiler_client.pl:  Main entry point for compiling snippets.  Sends over TCP to
                       compiler_server.pl.  This file can be run be run from the
                       client machine or anywhere.

- compiler_server.pl:  Responsible for setting up a TCP server to listen for
                       incoming compile requests; and launching and resetting
                       the virtual machine.  Sends to compiler_vm_client.pl.
                       Run this file on the server hosting the virtual machine.

- compiler_vm_client.pl: Responsible for sending snippets to the virtual
                         machine.  Also expands/translates and formats
                         snippets into compilable code (with main function and
                         headers), and handles "interactive-editing".
                         Sends over TCP to qemu serial port, waits for result,
                         then sends result back caller (compiler_server.pl).
                         Run this file on the server hosting the virtual machine.

- compiler_vm_server.pl: Runs on the system inside the virtual machine.
                         This script listens for incoming code snippets over
                         the virtual machine's serial port.
                         Calls compiler_watchdog.pl to monitor its exit signal
                         or exit status, then returns result back over serial
                         port (to compiler_vm_client.pl).

- compiler_watchdog.pl: Runs a program and watches its exit signals/status.
                        Run within the virtual machine.

*** The following files are just auxiliary tools to start/connect to qemu, provided
for convenience only.  Perhaps they will be useful during installation/testing:

- monitor: Connects to qemu monitor (internal console) over TCP.

- serial: Connects to qemu serial port over TCP.

- runqemu: Launches qemu with a visible window, but without networking support.

- runeqmu.net: Launches qemu with a visible window, and with networking support.
               You may load a state previously saved with runqemu and reboot it
               or otherwise reload its networking configuration to gain networking.