Reland "[netstack] Signal datagram socket errors"

This is a reland of 0883d1e5865ddf651a8ec88edf0ccc07aa7c00cb

This is safe to land once
https://chromium-review.googlesource.com/c/chromium/src/+/2819047 is
submitted.

Original change's description:
> [netstack] Signal datagram socket errors
>
> Before this change, netstack had no way to signal error conditions on
> datagram sockets. This change introduces a new zircon signal that can
> be polled in fdio.
>
> Test: fx test -od netstack_bsdsocket_c_api_test
>
> Bug: 69636
> Change-Id: Ie75e870b002406f7bffad9ec3ce1a95efe6f5b82
> Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/494320
> Commit-Queue: Arthur Sfez <asfez@google.com>
> Reviewed-by: Tamir Duberstein <tamird@google.com>
> Reviewed-by: Ghanan Gowripalan <ghanan@google.com>

Bug: 69636
Change-Id: I49cf417e8be623ab84de9f5216f96c5d66c4c66c
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/513509
Reviewed-by: Tamir Duberstein <tamird@google.com>
Commit-Queue: Tamir Duberstein <tamird@google.com>
4 files changed
tree: 8839af46bac9a4cc8610da1febdffc446a7ffcaf
  1. .clang-format
  2. .clang-tidy
  3. .git-blame-ignore-revs
  4. .gitattributes
  5. .gitignore
  6. .gn
  7. .style.yapf
  8. AUTHORS
  9. BUILD.gn
  10. CODE_OF_CONDUCT.md
  11. CONTRIBUTING.md
  12. LICENSE
  13. OWNERS
  14. PATENTS
  15. README.md
  16. boards/
  17. build/
  18. buildtools/
  19. bundles/
  20. docs/
  21. examples/
  22. garnet/
  23. products/
  24. rustfmt.toml
  25. scripts/
  26. sdk/
  27. src/
  28. third_party/
  29. tools/
  30. zircon/
README.md

Fuchsia

Pink + Purple == Fuchsia (a new operating system)

What is Fuchsia?

Fuchsia is a modular, capability-based operating system. Fuchsia runs on modern 64-bit Intel and ARM processors.

Fuchsia is an open source project with a code of conduct that we expect everyone who interacts with the project to respect.

Read more about Fuchsia's principles.

How can I build and run Fuchsia?

See Getting Started.

Where can I learn more about Fuchsia?

See fuchsia.dev.