From 42d3a50aa272ac9454ebe32f9b87fe496da37edf Mon Sep 17 00:00:00 2001
From: Tyler Veness <calcmogul@gmail.com>
Date: Tue, 9 Nov 2021 20:10:48 -0800
Subject: [PATCH] [hal] Check error codes during serial port initialization
 (#3712)

Throw if serial port init fails.

Fixes #2036.
---
 hal/src/main/native/athena/SerialPort.cpp | 27 ++++++++++++++++++-----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/hal/src/main/native/athena/SerialPort.cpp b/hal/src/main/native/athena/SerialPort.cpp
index 374986b05c..7d32f19433 100644
--- a/hal/src/main/native/athena/SerialPort.cpp
+++ b/hal/src/main/native/athena/SerialPort.cpp
@@ -83,7 +83,7 @@ HAL_SerialPortHandle HAL_InitializeSerialPortDirect(HAL_SerialPort port,
 
   serialPort->portId = open(portName, O_RDWR | O_NOCTTY);
   if (serialPort->portId < 0) {
-    *status = errno;
+    *status = -errno;
     if (*status == EACCES) {
       *status = HAL_CONSOLE_OUT_ENABLED_ERROR;
     }
@@ -94,8 +94,20 @@ HAL_SerialPortHandle HAL_InitializeSerialPortDirect(HAL_SerialPort port,
   std::memset(&serialPort->tty, 0, sizeof(serialPort->tty));
 
   serialPort->baudRate = B9600;
-  cfsetospeed(&serialPort->tty, static_cast<speed_t>(serialPort->baudRate));
-  cfsetispeed(&serialPort->tty, static_cast<speed_t>(serialPort->baudRate));
+  if (cfsetospeed(&serialPort->tty,
+                  static_cast<speed_t>(serialPort->baudRate)) != 0) {
+    *status = -errno;
+    close(serialPort->portId);
+    serialPortHandles->Free(handle);
+    return HAL_kInvalidHandle;
+  }
+  if (cfsetispeed(&serialPort->tty,
+                  static_cast<speed_t>(serialPort->baudRate)) != 0) {
+    *status = -errno;
+    close(serialPort->portId);
+    serialPortHandles->Free(handle);
+    return HAL_kInvalidHandle;
+  }
 
   serialPort->tty.c_cflag &= ~PARENB;
   serialPort->tty.c_cflag &= ~CSTOPB;
@@ -115,9 +127,14 @@ HAL_SerialPortHandle HAL_InitializeSerialPortDirect(HAL_SerialPort port,
    */
   serialPort->tty.c_oflag = ~OPOST;
 
-  tcflush(serialPort->portId, TCIOFLUSH);
+  if (tcflush(serialPort->portId, TCIOFLUSH) != 0) {
+    *status = -errno;
+    close(serialPort->portId);
+    serialPortHandles->Free(handle);
+    return HAL_kInvalidHandle;
+  }
   if (tcsetattr(serialPort->portId, TCSANOW, &serialPort->tty) != 0) {
-    *status = errno;
+    *status = -errno;
     close(serialPort->portId);
     serialPortHandles->Free(handle);
     return HAL_kInvalidHandle;