blog_os/blog/content/status-update/2020-03-02.md

+++ title = "Updates in February 2020" date = 2020-03-02 +++

This post gives an overview of the recent updates to the Writing an OS in Rust blog and the corresponding libraries and tools.

blog_os

The repository of the Writing an OS in Rust blog received the following updates:

• Mention potential bump allocator extensions
• Don't panic on overflow in allocator; return null pointer instead
  • Update Allocator Designs post to signal OOM instead of panicking on overflow
• Update to Zola 0.10
• Experimental Support for Community Translations
  • Add translations from rustcc/writing-an-os-in-rust
  • Some fixes to generated translations
  • Add metadata to translations and list translators
  • Add a language selector for browser-supported languages
• Use zola check to check for dead links; fix all dead links found
• Convert all external links to https (if supported)
• Mention in "Paging Introduction" that a CPU with 5-level paging is available now
• Double Faults: A missing handler leads to a #GP exception (not a #NP)
• Updated pc-keyboard to 0.5.0 by @RKennedy9064

x86_64

The x86_64 crate provides support for CPU-specific instructions, registers, and data structures of the x86_64 architecture. There were lots of great contributions this month:

• Add User Mode registers by @vinaychandra (released together with #118 as v0.9.0)
• Improve PageTableIndex and PageOffset by @m-ou-se (released as v0.9.1)
• Remove the cast dependency by @m-ou-se (released as v0.9.2)
• Fix GitHub actions to run latest available rustfmt by @m-ou-se
• Enable usage with non-nightly rust by @haraldh (released as v0.9.3)
  • asm: add target_env = "musl" to pickup the underscore asm names by @haraldh (released as v0.9.4)
• Add #[inline] attribute to small functions by @AntoineSebert (released as v0.9.5)
• Fix clippy warnings by @AntoineSebert
  • Resolve remaining clippy warnings and add clippy job to CI

bootloader

The bootloader crate received two small bugfixes and one new feature this month:

• Objcopy replaces . chars with _ chars (released as v0.8.6)
• Fix docs.rs build by specifying an explicit target (released as v0.8.7)
• Add basic support for ELF thread local storage segments (released as v0.8.8)

bootimage

There were no updates to the bootimage tool this month.

cargo-xbuild

The cargo-xbuild crate provides support for cross-compiling libcore and liballoc. It received the following contributions this month:

• Added new option to the configuration table by @parraman (released an v0.5.22)
• Pick up xbuild config from workspace manifest by @ascjones (released as v0.5.23)
• Make fn build and Args public to enable use as lib by @ascjones (released as v0.5.24)
• Fix: Not all projects have a root package (released as v0.5.25)
• Improvements to args and config for lib usage by @ascjones (released as v0.5.26)
• Add cargo xfix command by @tjhu (released as v0.5.27)
• Update dependencies by @parasyte (released as v0.5.28)

uart_16550

The uart_16550 crate, which provides basic support for uart_16550 serial output, received the following updates:

• Switch CI to GitHub Actions
• Cargo.toml: update x86_64 dependency by @haraldh (released as v0.2.3)
• Enable usage with non-nightly rust by @haraldh (released as v0.2.4)

multiboot2-elf64

The multiboot2-elf64 crate provides abstractions for reading the boot information of the multiboot 2 standard, which is implemented by bootloaders like GRUB. There were two updates to the crate in February:

• Add MemoryAreaType, to allow users to access memory area types in a type-safe way by @CWood1
• Add some basic documentation by @mental32 (released as v0.8.2)