Some general cleanups in the HAL (#188)

AnalogTrigger initialization checks are now in the correct order. Plus
frees no longer grab the structure if it is not needed.

hal/lib/athena/Accelerometer.cpp

@@ -9,6 +9,7 @@
 
 #include <cassert>
 #include <cstdio>
+#include <memory>
 
 #include <stdint.h>
 
@@ -25,7 +26,7 @@ static const uint8_t kControlTxRx = 1;
 static const uint8_t kControlStart = 2;
 static const uint8_t kControlStop = 4;
 
-static tAccel* accel = 0;
+static std::unique_ptr<tAccel> accel;
 static HAL_AccelerometerRange accelerometerRange;
 
 // Register addresses
@@ -84,7 +85,7 @@ static void initializeAccelerometer() {
   int32_t status;
 
   if (!accel) {
-    accel = tAccel::create(&status);
+    accel.reset(tAccel::create(&status));
 
     // Enable I2C
     accel->writeCNFG(1, &status);
@@ -124,8 +125,6 @@ static void writeRegister(Register reg, uint8_t data) {
   while (accel->readSTAT(&status) & 1) {
     if (HAL_GetFPGATime(&status) > initialTime + 1000) break;
   }
-
-  std::fflush(stdout);
 }
 
 static uint8_t readRegister(Register reg) {
@@ -155,8 +154,6 @@ static uint8_t readRegister(Register reg) {
     if (HAL_GetFPGATime(&status) > initialTime + 1000) break;
   }
 
-  std::fflush(stdout);
-
   return accel->readDATI(&status);
 }
 

hal/lib/athena/AnalogInput.cpp

@@ -63,8 +63,6 @@ HAL_AnalogInputHandle HAL_InitializeAnalogInputPort(HAL_PortHandle port_handle,
 }
 
 void HAL_FreeAnalogInputPort(HAL_AnalogInputHandle analog_port_handle) {
-  auto port = analogInputHandles.Get(analog_port_handle);
-  if (!port) return;
   // no status, so no need to check for a proper free.
   analogInputHandles.Free(analog_port_handle);
 }

hal/lib/athena/AnalogTrigger.cpp

@@ -32,26 +32,25 @@ extern "C" {
 
 HAL_AnalogTriggerHandle HAL_InitializeAnalogTrigger(
     HAL_AnalogInputHandle port_handle, int32_t* index, int32_t* status) {
-  if (port_handle == HAL_kInvalidHandle) {
-    *status = PARAMETER_OUT_OF_RANGE;
+  // ensure we are given a valid and active AnalogInput handle
+  auto analog_port = analogInputHandles.Get(port_handle);
+  if (analog_port == nullptr) {
+    *status = HAL_HANDLE_ERROR;
     return HAL_kInvalidHandle;
   }
-  HAL_AnalogInputHandle handle = analogTriggerHandles.Allocate();
+  HAL_AnalogTriggerHandle handle = analogTriggerHandles.Allocate();
   if (handle == HAL_kInvalidHandle) {
     *status = NO_AVAILABLE_RESOURCES;
     return HAL_kInvalidHandle;
   }
   auto trigger = analogTriggerHandles.Get(handle);
-  trigger->analogHandle = port_handle;
-
-  auto analog_port = analogInputHandles.Get(trigger->analogHandle);
-  if (analog_port == nullptr) {  // would only error on thread issue
+  if (trigger == nullptr) {  // would only occur on thread issue
     *status = HAL_HANDLE_ERROR;
     return HAL_kInvalidHandle;
   }
+  trigger->analogHandle = port_handle;
   trigger->index = static_cast<uint8_t>(getHandleIndex(handle));
   *index = trigger->index;
-  // TODO: if (index == ~0ul) { CloneError(triggers); return; }
 
   trigger->trigger.reset(tAnalogTrigger::create(trigger->index, status));
   trigger->trigger->writeSourceSelect_Channel(analog_port->pin, status);
@@ -60,10 +59,6 @@ HAL_AnalogTriggerHandle HAL_InitializeAnalogTrigger(
 
 void HAL_CleanAnalogTrigger(HAL_AnalogTriggerHandle analog_trigger_handle,
                             int32_t* status) {
-  auto trigger = analogTriggerHandles.Get(analog_trigger_handle);
-  if (trigger == nullptr) {  // ignore status error
-    return;
-  }
   analogTriggerHandles.Free(analog_trigger_handle);
   // caller owns the analog input handle.
 }

hal/lib/athena/Counter.cpp

@@ -49,10 +49,6 @@ HAL_CounterHandle HAL_InitializeCounter(HAL_Counter_Mode mode, int32_t* index,
 }
 
 void HAL_FreeCounter(HAL_CounterHandle counter_handle, int32_t* status) {
-  auto counter = counterHandles.Get(counter_handle);
-  if (counter == nullptr) {  // don't throw status as unneccesary
-    return;
-  }
   counterHandles.Free(counter_handle);
 }
 

hal/lib/athena/FPGAEncoder.cpp

@@ -84,12 +84,7 @@ HAL_FPGAEncoderHandle HAL_InitializeFPGAEncoder(
 
 void HAL_FreeFPGAEncoder(HAL_FPGAEncoderHandle fpga_encoder_handle,
                          int32_t* status) {
-  auto encoder = fpgaEncoderHandles.Get(fpga_encoder_handle);
   fpgaEncoderHandles.Free(fpga_encoder_handle);
-  if (encoder == nullptr) {
-    *status = HAL_HANDLE_ERROR;
-    return;
-  }
 }
 
 /**

hal/lib/athena/Interrupts.cpp

@@ -52,11 +52,6 @@ HAL_InterruptHandle HAL_InitializeInterrupts(HAL_Bool watcher,
 
 void HAL_CleanInterrupts(HAL_InterruptHandle interrupt_handle,
                          int32_t* status) {
-  auto anInterrupt = interruptHandles.Get(interrupt_handle);
-  if (anInterrupt == nullptr) {
-    *status = HAL_HANDLE_ERROR;
-    return;
-  }
   interruptHandles.Free(interrupt_handle);
 }