Implement hexagram_cluster_update()

Implement hexagram_cluster_update() to act as a central point to decode
CAN frames relevant to the gauge cluster

examples/cluster.c

@@ -45,36 +45,8 @@ static void cluster_update(hexagram_cluster *cluster,
                            struct timeval *last) {
     struct timeval now;
 
-    switch (frame->can_id) {
+    if (!hexagram_cluster_update(cluster, frame)) {
-        case 0x280: {
+        return;
-            cluster->state.rpm = 0.25 *
-                (double)(frame->data[2] | (frame->data[3] << 8));
-
-            break;
-        }
-
-        case 0x288: {
-            cluster->state.temp = (double)(frame->data[1] - 48 * 0.75);
-
-            break;
-        }
-
-        case 0x320: {
-            cluster->state.fuel = (double)(frame->data[2] & 0xf) / 16.0;
-
-            break;
-        }
-
-        case 0x5a0: {
-            cluster->state.rps = 0.001 * (double)(frame->data[1]
-                                               | (frame->data[2] << 8));
-
-            break;
-        }
-
-        default: {
-            return;
-        }
     }
 
     gettimeofday(&now, NULL);

include/hexagram/cluster.h

@@ -1,6 +1,8 @@
 #ifndef _HEXAGRAM_CLUSTER_H
 #define _HEXAGRAM_CLUSTER_H
 
+#include <linux/can.h>
+
 #include <cairo.h>
 
 #include <hexagram/tacho.h>
@@ -35,6 +37,9 @@ void hexagram_cluster_init(hexagram_cluster *cluster,
 hexagram_cluster *hexagram_cluster_new(double width,
                                        double height);
 
+int hexagram_cluster_update(hexagram_cluster *cluster,
+                            struct can_frame *frame);
+
 void hexagram_cluster_draw_bg(hexagram_cluster *cluster,
                               cairo_t *cr);
 

src/cluster.c

@@ -71,6 +71,39 @@ error_malloc_cluster:
     return NULL;
 }
 
+int hexagram_cluster_update(hexagram_cluster *cluster,
+                            struct can_frame *frame) {
+    switch (frame->can_id) {
+        case 0x280: {
+            cluster->state.rpm = 0.25 *
+                (double)(frame->data[2] | (frame->data[3] << 8));
+
+            return 1;
+        }
+
+        case 0x288: {
+            cluster->state.temp = (double)(frame->data[1] - 48 * 0.75);
+
+            return 1;
+        }
+
+        case 0x320: {
+            cluster->state.fuel = (double)(frame->data[2] & 0xf) / 16.0;
+
+            return 1;
+        }
+
+        case 0x5a0: {
+            cluster->state.rps = 0.001 * (double)(frame->data[1]
+                                               | (frame->data[2] << 8));
+
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
 void hexagram_cluster_draw_bg(hexagram_cluster *cluster,
                               cairo_t *cr) {
     /*