Clean up bit length lookup

Author: jacobmcnamee

src/bit_sync.c

@@ -22,8 +22,15 @@
 #define BITSYNC_THRES 22
 
 /* Bit lengths for different constellations. Bounded by BIT_LENGTH_MAX */
-#define BIT_LENGTH_GPS_L1 20
-#define BIT_LENGTH_SBAS_L1 2
+#define BIT_LENGTH_GPS_L1CA 20
+#define BIT_LENGTH_SBAS_L1CA 2
+
+/* Table of bit lengths for each code type */
+static const u8 bit_length_table[CODE_COUNT] = {
+  [CODE_GPS_L1CA] = BIT_LENGTH_GPS_L1CA,
+  [CODE_GPS_L2CM] = 0,
+  [CODE_SBAS_L1CA] = BIT_LENGTH_SBAS_L1CA
+};
 
 static void histogram_update(bit_sync_t *b, s32 corr_prompt_real);
 
@@ -39,20 +46,16 @@ static void histogram_update(bit_sync_t *b, s32 corr_prompt_real);
  */
 void bit_sync_init(bit_sync_t *b, gnss_signal_t sid)
 {
+  assert(sid_valid(sid));
   memset(b, 0, sizeof(bit_sync_t));
   b->bit_phase_ref = BITSYNC_UNSYNCED;
 
-  assert(sid.code == CODE_GPS_L1CA || sid.code == CODE_SBAS_L1CA);
-  switch (sid.code) {
-  case CODE_GPS_L1CA:
-    b->bit_length = BIT_LENGTH_GPS_L1;
-    break;
-  case CODE_SBAS_L1CA:
-    b->bit_length = BIT_LENGTH_SBAS_L1;
-    break;
-  default:
-    assert("unsupported code");
+  u8 bit_length = bit_length_table[sid.code];
+  if (bit_length == 0) {
+    assert(!"Unsupported code type");
+    bit_length = 1;
   }
+  b->bit_length = bit_length;
 }
 
 /** Update bit sync and get bit integration output