Managed file descriptors, loading dynamic executables

[fwsGonzo]

This allows managing file descriptors from TinyKVM. More work is needed to cover all use-cases.

[Copilot]

Pull Request Overview

This PR introduces basic support for managing file descriptors in TinyKVM. Key changes include replacing and adding header includes to support Linux-specific functionality, adding new methods in Machine for file descriptor handling, and implementing file descriptor management in new files (fds.hpp and fds.cpp).

Reviewed Changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
lib/tinykvm/machine.hpp	Replaced signals include with linux-specific ones and added declarations for file descriptor accessors
lib/tinykvm/machine.cpp	Updated inclusion of thread headers
lib/tinykvm/linux/threads.hpp & .cpp	Updated relative paths to headers
lib/tinykvm/linux/signals.hpp & .cpp	Updated relative paths to headers and implemented sigaction
lib/tinykvm/linux/fds.hpp	New header providing file descriptor management definitions
lib/tinykvm/linux/fds.cpp	New implementation for managing file descriptors

Files not reviewed (1)

• lib/CMakeLists.txt: Language not supported

Comments suppressed due to low confidence (1)

lib/tinykvm/linux/fds.cpp:88

• [nitpick] The variable name 'gucci_path' is overly informal and may be unclear to other developers. Consider renaming it to 'allowed_path'.

for (const auto& gucci_path : this->m_allowed_paths)

[fwsGonzo]

At this point, it's enough to load a simple glibc hello world! A C++ shared executable is failing on something, which looks to be a trashed stack. However, Rust programs only depend on glibc, which in theory means that Rust default builds should now be loadable in TinyKVM.