tree 9a35a5d08f47b7b782390c664727971d8550e1fd
parent 376cbc1f50b431a59f2996405126172ab29bfe20
author Wyatt Hepler <hepler@google.com> 1675296967 +0000
committer CQ Bot Account <pigweed-scoped@luci-project-accounts.iam.gserviceaccount.com> 1675296967 +0000

pw_rpc: Fix callback synchronization issues

- Move the on_next callback to a local variable while the lock is
  held, then invoke it. Restore on_next when done, if the call has not
  been closed or on_next changed since.
- Track whether callbacks are executing in the call object.
- If a new stream packet arrives while another callback is running, drop
  it since the on_next callback is not available.
- Hold the lock while invoking on_next or on_completed callback wrappers
  that decode to a Nanopb or pwpb struct.
- Guard the serde objects with the RPC lock.
- Wait until callbacks complete before moving or destroying a call
  object. This helps prevent dangling references in RPC callbacks.

Bug: b/234876851, b/262774186
Change-Id: I9d853001dc27abef0c1fade0057d1da635f622cb
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/126919
Pigweed-Auto-Submit: Wyatt Hepler <hepler@google.com>
Reviewed-by: Khalil Estell <kammce@google.com>
Reviewed-by: Alexei Frolov <frolv@google.com>
Commit-Queue: Auto-Submit <auto-submit@pigweed.google.com.iam.gserviceaccount.com>