Invert midi_read return value

crowbx.c

@@ -32,7 +32,7 @@ void uart_buffer_push(uint8_t x) {
 uint8_t uart_buffer_pop(uint8_t *x) {
 	ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
 		if (uart_buffer.head == uart_buffer.tail) {
-			return 1; // error: uart_buffer is empty
+			return false; // error: uart_buffer is empty
 		}
 
 		*x = uart_buffer.data[uart_buffer.head];
@@ -40,7 +40,7 @@ uint8_t uart_buffer_pop(uint8_t *x) {
 		    (uart_buffer.head + 1) % ARRAY_SIZE(uart_buffer.data);
 	}
 
-	return 0;
+	return true;
 }
 
 ISR(USART_RX_vect) {
@@ -171,13 +171,13 @@ int main(void) {
 		do_clock_update();
 
 		uint8_t status, data1, data2;
-		if (midi_read(&status, &data1, &data2) != MIDI_READ_OK) {
+		if (!midi_read(&status, &data1, &data2)) {
 			continue;
 		}
 
 		switch (status) {
 		case MIDI_NOTE_ON:
-			if (data2 > 0) {
+			if (data2) {
 				programs[current_program].note_on(data1);
 			} else {
 				programs[current_program].note_off(data1);

midi-test.h

@@ -13,8 +13,8 @@ uint8_t midi_load(uint8_t *status, uint8_t *data1, uint8_t *data2);
 	{                                                                      \
 		uint8_t _status, _avail, _data1, _data2;                       \
 		_avail = midi_load(&_status, &_data1, &_data2);                \
-		assert((_avail != MIDI_READ_OK) == !avail);                    \
-		if (_avail == MIDI_READ_OK) {                                  \
+		assert(!_avail == !avail);                                     \
+		if (_avail) {                                                  \
 			assert(((_data1 << 8) | _data2) == data);              \
 			assert(_status == status);                             \
 		}                                                              \
@@ -24,8 +24,8 @@ uint8_t midi_load(uint8_t *status, uint8_t *data1, uint8_t *data2);
 	{                                                                      \
 		uint8_t _status, _avail, _data1, _data2;                       \
 		_avail = midi_load(&_status, &_data1, &_data2);                \
-		assert((_avail != MIDI_READ_OK) == !avail);                    \
-		if (_avail == MIDI_READ_OK) {                                  \
+		assert(!_avail == !avail);                                     \
+		if (_avail) {                                                  \
 			assert((_data1 << 8) == data1);                        \
 			assert(_status == status);                             \
 		}                                                              \

midi.c

@@ -18,7 +18,7 @@ const uint8_t statuses[] = {
     [MIDI_PITCH_BEND] = 0b1110,
 };
 
-uint8_t midi_data_available(void) {
+bool midi_data_available(void) {
 	if (midi.status == MIDI_PROGRAM_CHANGE) {
 		return midi.data_received == 1;
 	}
@@ -69,22 +69,18 @@ void midi_parse(uint8_t b) {
 void midi_init() { midi_status_init(); }
 
 uint8_t midi_load(uint8_t *status, uint8_t *data1, uint8_t *data2) {
-	if (!midi_data_available()) {
-		return MIDI_READ_NO_DATA;
-	}
-
 	*status = midi.status;
 	*data1 = midi.data[0];
 	*data2 = midi.data[1];
 
-	return MIDI_READ_OK;
+	return midi_data_available();
 }
 
-uint8_t midi_read(uint8_t *status, uint8_t *data1, uint8_t *data2) {
+bool midi_read(uint8_t *status, uint8_t *data1, uint8_t *data2) {
 	uint8_t uart_data;
 
-	if (uart_read(&uart_data)) {
-		return MIDI_READ_NO_DATA;
+	if (!uart_read(&uart_data)) {
+		return false;
 	}
 
 	midi_parse(uart_data);

midi.h

 #ifndef MIDI_H
 #define MIDI_H
 
+#include <stdbool.h>
 #include <stdint.h>
 
 enum _statuses {
@@ -24,10 +25,6 @@ enum _cc {
 void midi_init(void);
 void midi_set_channel(uint8_t channel);
 
-enum { MIDI_READ_OK,
-       MIDI_READ_NO_DATA,
-};
-
-uint8_t midi_read(uint8_t *status, uint8_t *data1, uint8_t *data2);
+bool midi_read(uint8_t *status, uint8_t *data1, uint8_t *data2);
 
 #endif