Resolve a race condition around the radio interrupt

lantern/main.c

@@ -30,7 +30,6 @@ You should have received a copy of the GNU General Public License along with thi
 
 typedef struct {
     bool frame_timeout;
-    bool message_arrived;
 } status_flags_t;
 
 status_flags_t status_flags;
@@ -40,7 +39,6 @@ ISR(TIMER1_COMPA_vect) {
 }
 
 ISR(INT6_vect) {
-    status_flags.message_arrived = true;
 }
 
 void setup_fps_timer(void) {
@@ -62,11 +60,6 @@ int main(void) {
     EICRA |= 1 << ISC21 | 1 << ISC20;
     EICRB |= 1 << ISC61 | 1 << ISC60;
 
-    /*
-    for (int i = 0; i < 4; i++) {
-        status_flags.button_press[i] = false;
-    }
-    */
     status_flags.frame_timeout = false;
 
     // Disable unneeded modules
@@ -88,32 +81,39 @@ int main(void) {
     rfm_init(&radio, (uint8_t [4]){ 0xde, 0xca, 0xfb, 0xad }, 4, &error);
     rfm_listen(&radio);
 
-    /*
-    display_t display = {
-        .reg = {
-            .output         = { .ddr = &DDRF, .port = &PORTF, .pin = &PINF, .addr = 7 },
-            .shift_clock    = { .ddr = &DDRF, .port = &PORTF, .pin = &PINF, .addr = 6 },
-            .latch_clock    = { .ddr = &DDRF, .port = &PORTF, .pin = &PINF, .addr = 5 },
-        }
-    };
-
-    display_init(&display);
-    display_write_message(&display, "ready");
-    _delay_ms(1000);
-    */
-
-    /*
-    for (int i = 0; i < 4; i++) {
-        dio_set_direction(&buttons[i], LINE_IN);
-    }
-    */
-
     sk9822_t lights = {
         .clock_pin = { .ddr = &DDRC, .port = &PORTC, .pin = &PINC, .addr = 7 },
         .data_pin = { .ddr = &DDRD, .port = &PORTD, .pin = &PIND, .addr = 6 }
     };
 
     rgb_t colors[LIGHT_COUNT];
+    rgb_t off[LIGHT_COUNT] = {
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+    };
+    /*
+    rgb_t error_indicator[LIGHT_COUNT] = {
+        { .brightness = 1, .r = 255, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+        { .brightness = 0, .r = 0, .g = 0, .b = 0 },
+    };
+    */
+
+    sk9822_send(&lights, off, LIGHT_COUNT);
+    _delay_ms(500);
 
     lantern_t lantern = lantern_new(lights);
     lantern_set_mode(&lantern, normal);
@@ -129,34 +129,33 @@ int main(void) {
             status_flags.frame_timeout = false;
             lantern_step(&lantern, colors);
             sk9822_send(&lights, colors, LIGHT_COUNT);
-        } else if (status_flags.message_arrived) {
+        }
-            status_flags.message_arrived = false;
+
-            char msg[60];
+
-            uint8_t length;
         interrupt_flags_t flags = rfm_interrupts(&radio);
         while (flags.fifo_not_empty) {
+            /*
+            sk9822_send(&lights, off, LIGHT_COUNT);
+            _delay_ms(100);
+            */
+            char msg[60] = "";
+            uint8_t length;
+
             rfm_receive(&radio, (uint8_t *)msg, &length);
-                if (!strncmp(msg, "normal", strlen("normal"))) {
+            if (length == strlen("normal") + 1 && !strncmp(msg, "normal", length)) {
                 lantern_set_mode(&lantern, normal);
-                } else if (!strncmp(msg, "spooky", strlen("spooky"))) {
+            } else if (length == strlen("spooky") + 1 && !strncmp(msg, "spooky", length)) {
                 lantern_set_mode(&lantern, spooky);
-                } else if (!strncmp(msg, "eerie", strlen("eerie"))) {
+            } else if (length == strlen("eerie") + 1 && !strncmp(msg, "eerie", length)) {
                 lantern_set_mode(&lantern, eerie);
+                /*
+            } else {
+                sk9822_send(&lights, error_indicator, LIGHT_COUNT);
+                _delay_ms(500);
+                */
             }
             flags = rfm_interrupts(&radio);
         }
-        }
-        /*
-        if (status_flags.button_press[0]) {
-            status_flags.button_press[0] = false;
-            lantern_set_mode(&lantern, normal);
-        } else if (status_flags.button_press[1]) {
-            status_flags.button_press[1] = false;
-            lantern_set_mode(&lantern, spooky);
-        } else if (status_flags.button_press[2]) {
-            status_flags.button_press[2] = false;
-            lantern_set_mode(&lantern, eerie);
-        */
 
         sei();
         sleep_mode();