wpilibsuite/allwpilib

Document thread safety guarantees of HAL SerialPort initialization

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#2,035 opened on Nov 3, 2019

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component: halgood first issuetype: docs

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Description

I'm not sure anyone is actually using serial ports from multiple threads, but given that most things in the HAL seem to be written in a way that tries to be thread-safe, I'm assuming that the calls to, e.g., HAL_InitializeSerialPort and HAL_CloseSerial and all the other serial calls defined in hal/src/main/native/athena/SerialPort.cpp are intended to be safe to call from multiple threads.

Currently, after any of the calls to serialPortHandles->Get, there is no longer a mutex protecting access to the SerialPort.

Contributor guide

Research direction
Analyze the SerialPort.cpp code for mutex usage and add documentation comments specifying thread safety guarantees for each function.
Tech stack
cpp
Domain
embedded iot
Issue type
Documentation
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
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1-3 hours
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Active
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Clear
Prerequisites
C++Git
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70