commit 6ae057c48564ac41c288c3f211bbe5863f68ed5b
author Ali Zhang <alizhang@google.com> Fri Jul 30 14:17:55 2021 -0700
committer CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Aug 24 07:17:19 2021 +0000
tree 3f25d81656566ca61526bafcef8ba36f1cd72e9e
parent 1829982bd541d899d43cacd23e4a1e2621ce707d

pw_crypto: Refactor Sha256

1. Extracts state tracking from backends to the facade, with tests
   against a mocked backend.

2. Makes Sha256::Update() chainable. e.g.
   ```
   if (!Sha256().Update(message).Update(more_message).Final().ok()) {
       // Handle errors.
   }
   ```
   All usage and documentation are updated accordingly.

3. Inlines Sha256::Sha256()/Update()/Final() in sha256.h, removes
   sha256.cc.

4. Other trivial clean ups.

Test:
  - `pw presubmit`
  - `pw presubmit --step gn_crypto_(mbedtls|boringssl|micro_ecc)_build`

Change-Id: I1c9e09c4640472ff2bbff8853e076bd2ed9188d3
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/55343
Commit-Queue: Ali Zhang <alizhang@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>
Pigweed-Auto-Submit: Ali Zhang <alizhang@google.com>
Reviewed-by: Keir Mierle <keir@google.com>