GSoC: Separation of Ports Build Process from Local Installation

[Theron Tarigo]

Hello all,

This project aims to decouple the build process of the ports framework 
from the local installation.  To work around the assumptions made by 
ports about dependency file locations, a userspace tool to remap 
processes' filesystem namespaces is under development.

This past week, I have made the following progress:
- Switched bsd.port.mk from using a chroot for namespace manipulation to 
using the userspace namespace tool.
- Enabled namespace tool to read path mappings from environment, 
supplied by bsd.port.mk
- Re-ran port builds.  Several problems which had not occurred when 
using chroot became introduced.
- Studied interactions between executables, namespace tool, dynamic 
linker, and standard library to understand the cases in which file 
accesses fail to be intercepted.

What I am working on next:
- Research, design, implement, and test appropriate solutions for the 
problems encountered with userspace file access interception.

Project goals and status are kept at 
https://wiki.freebsd.org/SummerOfCode2019Projects/PortsSeparatedBuild .

Source of the userspace filesystem namespace tool is shared at 
https://github.com/therontarigo/freebsd-user-namespace .
Changes to ports framework are shared at 
https://github.com/freebsd/freebsd-ports/compare/master...therontarigo:master 
.

Theron Tarigo