Refactor data_manager to use contexts

This should be more testable and flexible. Note that the barometer has internal
non-resettable state which enforces a certain test order. This should be fixed
soon.

4 files changed, 24 insertions, 68 deletions

diff --git a/altimeter.c b/altimeter.c
index 77c897e..861b054 100644
--- a/altimeter.c
+++ b/altimeter.c
@@ -34,10 +34,12 @@
 #define DEBUG_MARK_5_SET   do{PORTB |= 1 << 5;}while(0)
 #define DEBUG_MARK_5_CLEAR do{PORTB &= ~(1 << 5);}while(0)
 
+static struct data_ctx dctx = {};
+
 /* ISR for collecting and displaying pressure, altitude data etc */
 ISR(TIMER1_COMPA_vect)
 {
-	data_manager_tick();
+	data_manager_tick(&dctx);
 	//ui_tick();
 
 	WDT_PAT_MAYBE();
@@ -48,7 +50,7 @@ int main(void)
 	/* Initialise display before enabling interrupts */
 	display_init();
 	display_clear();
-	data_manager_init();
+	data_manager_init(&dctx);
 
 	DEBUG_INIT;
 
diff --git a/data_manager.c b/data_manager.c
index 62dcd14..76a70c7 100644
--- a/data_manager.c
+++ b/data_manager.c
@@ -5,9 +5,6 @@
 #include "data_manager.h"
 #include "barometer.h"
 
-static float pressure[PRESSURE_UNIT_MAX];
-static float setting[PRESSURE_UNIT_MAX];
-static float altitude[ALTITUDE_UNIT_MAX];
 
 /* utility functions */
 static float pressure_to_metres_asl(float real, float setting)
@@ -15,57 +12,20 @@ static float pressure_to_metres_asl(float real, float setting)
 	return 44330.f*(1.f-powf(real/setting, 1/5.255));
 }
 
-
-/* exported functions */
-#define DATA_MANAGER_GETTER(name, store, bound, enum_type, return_type) \
-float name(enum_type unit) \
-{ \
-	if (unit >= 0 && unit < bound) { \
-		return store[unit]; \
-	} else { \
-		abort(); \
-	} \
-}
-
-DATA_MANAGER_GETTER(
-	data_manager_get_pressure,
-	pressure,
-	PRESSURE_UNIT_MAX,
-	enum pressure_unit,
-	float)
-DATA_MANAGER_GETTER(
-	data_manager_get_setting,
-	setting,
-	PRESSURE_UNIT_MAX,
-	enum pressure_unit,
-	float)
-DATA_MANAGER_GETTER(
-	data_manager_get_altitude,
-	altitude,
-	ALTITUDE_UNIT_MAX,
-	enum altitude_unit,
-	float)
-
-void data_manager_init(void)
+void data_manager_init(struct data_ctx *ctx)
 {
-	/* FIXME load initial setting and force a tick synchronously */
-	setting[PRESSURE_UNIT_HPA] = 1013.25;
-	data_manager_tick();
+	ctx->setting = 1013.25;
+	data_manager_tick(ctx);
 }
 
-void data_manager_tick(void)
+void data_manager_tick(struct data_ctx *ctx)
 {
 	/* FIXME alt rate */
 	/* FIXME calculate on demand? */
-	/* FIXME hardcoding the conversion factors here is gross */
-	float p = barometer_read();
-	pressure[PRESSURE_UNIT_HPA] = p;
-	pressure[PRESSURE_UNIT_INHG] = p / 3.38639;
+	ctx->pressure = barometer_read();
 
 	/* FIXME we need atomic access to alt setting once user can set it. Check
 	 * if AVR allows multiple/nested ISRs to run concurrently, pretty sure not
 	 */
-	float a = pressure_to_metres_asl(p, setting[PRESSURE_UNIT_HPA]);
-	altitude[ALTITUDE_UNIT_METRE] = a;
-	altitude[ALTITUDE_UNIT_FT] = a * 3.048;
+	ctx->altitude = pressure_to_metres_asl(ctx->pressure, ctx->setting);
 }
diff --git a/data_manager.h b/data_manager.h
index 293d7d5..83126f6 100644
--- a/data_manager.h
+++ b/data_manager.h
@@ -1,18 +1,10 @@
 #pragma once
 
-enum pressure_unit {
-	PRESSURE_UNIT_HPA,
-	PRESSURE_UNIT_INHG,
-	PRESSURE_UNIT_MAX
+struct data_ctx {
+	float setting;
+	float pressure;
+	float altitude;
 };
 
-enum altitude_unit {
-	ALTITUDE_UNIT_METRE,
-	ALTITUDE_UNIT_FT,
-	ALTITUDE_UNIT_MAX
-};
-
-float data_manager_get_setting(enum pressure_unit);
-float data_manager_get_pressure(enum pressure_unit);
-void data_manager_init(void);
-void data_manager_tick(void);
+void data_manager_init(struct data_ctx*);
+void data_manager_tick(struct data_ctx*);
diff --git a/test_data_manager.c b/test_data_manager.c
index 8edd781..4673cab 100644
--- a/test_data_manager.c
+++ b/test_data_manager.c
@@ -4,14 +4,16 @@
 
 RUNNER_DECLARE_TEST(test_data_manager_init_setting)
 {
-	data_manager_init();
-	TEST_ASSERT_FLOAT_WITHIN(0.001, 1013.25, data_manager_get_setting(PRESSURE_UNIT_HPA));
+	struct data_ctx ctx;
+	data_manager_init(&ctx);
+	TEST_ASSERT_FLOAT_WITHIN(0.001, 1013.25, ctx.setting);
 }
 
 RUNNER_DECLARE_TEST(test_data_manager_first_readings)
 {
-	data_manager_init();
-	TEST_ASSERT_FLOAT_WITHIN(0.001, 1019.5, data_manager_get_pressure(PRESSURE_UNIT_HPA));
-	data_manager_tick();
-	TEST_ASSERT_FLOAT_WITHIN(0.001, 1019.45, data_manager_get_pressure(PRESSURE_UNIT_HPA));
+	struct data_ctx ctx;
+	data_manager_init(&ctx);
+	TEST_ASSERT_FLOAT_WITHIN(0.001, 1019.5, ctx.pressure);
+	data_manager_tick(&ctx);
+	TEST_ASSERT_FLOAT_WITHIN(0.001, 1019.45, ctx.pressure);
 }