mirror of
https://github.com/rust-lang/rust.git
synced 2026-01-20 04:40:37 +00:00
55c7a02a8b
uefi: Implement path This PR is split off from https://github.com/rust-lang/rust/pull/135368 to reduce noise. UEFI paths can be of 4 types: 1. Absolute Shell Path: Uses shell mappings 2. Absolute Device Path: this is what we want 3. Relative root: path relative to the current root. 4. Relative Absolute shell path can be identified with `:` and Absolute Device path can be identified with `/`. Relative root path will start with `\`. The algorithm is mostly taken from edk2 UEFI shell implementation and is somewhat simple. Check for the path type in order. For Absolute Shell path, use `EFI_SHELL->GetDevicePathFromMap` to get a BorrowedDevicePath for the volume. For Relative paths, we use the current working directory to construct the new path. BorrowedDevicePath abstraction is needed to interact with `EFI_SHELL->GetDevicePathFromMap` which returns a Device Path Protocol with the lifetime of UEFI shell. Absolute Shell paths cannot exist if UEFI shell is missing. cc `@nicholasbishop`