Add option to disable CRC calculation

MaJerle · Feb 28, 2021 · 6fbcf34 · 6fbcf34
1 parent adce7a2
commit 6fbcf34
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Showing 3 changed files with 19 additions and 0 deletions.
diff --git a/lwgps/src/include/lwgps/lwgps.h b/lwgps/src/include/lwgps/lwgps.h
@@ -159,7 +159,9 @@ typedef struct {
 
         uint8_t star;                           /*!< Star detected flag */
 
+#if LWGPS_CFG_CRC
         uint8_t crc_calc;                       /*!< Calculated CRC string */
+#endif /* LWGPS_CFG_CRC */
 
         union {
             uint8_t dummy;                      /*!< Dummy byte */

diff --git a/lwgps/src/include/lwgps/lwgps_opt.h b/lwgps/src/include/lwgps/lwgps_opt.h
@@ -158,6 +158,15 @@ extern "C" {
 #define LWGPS_CFG_STATEMENT_PUBX_TIME       0
 #endif
 
+/**
+ * \brief           Enables `1` or disables `0` CRC calculation and check
+ *
+ * \note            When not enabled, CRC check is ignored
+ */
+#ifndef LWGPS_CFG_CRC
+#define LWGPS_CFG_CRC                       1
+#endif
+
 /* Guard against accidental parser breakage */
 #if LWGPS_CFG_STATEMENT_PUBX_TIME && !LWGPS_CFG_STATEMENT_PUBX
 #error LWGPS_CFG_STATEMENT_PUBX must be enabled when enabling LWGPS_CFG_STATEMENT_PUBX_TIME

diff --git a/lwgps/src/lwgps/lwgps.c b/lwgps/src/lwgps/lwgps.c
@@ -41,7 +41,11 @@
 #define R2D(x)              FLT(FLT(x) * FLT(57.29577951308232))/*!< Radians to degrees */
 #define EARTH_RADIUS        FLT(6371.0)         /*!< Earth radius in units of kilometers */
 
+#if LWGPS_CFG_CRC
 #define CRC_ADD(_gh, ch)    (_gh)->p.crc_calc ^= (uint8_t)(ch)
+#else
+#define CRC_ADD(_gh, ch)
+#endif /* LWGPS_CFG_CRC */
 #define TERM_ADD(_gh, ch)   do {    \
         if ((_gh)->p.term_pos < (sizeof((_gh)->p.term_str) - 1)) {  \
             (_gh)->p.term_str[(_gh)->p.term_pos] = (ch);\
@@ -346,6 +350,7 @@ prv_parse_term(lwgps_t* gh) {
     return 1;
 }
 
+#if LWGPS_CFG_CRC
 /**
  * \brief           Compare calculated CRC with received CRC
  * \param[in]       gh: GPS handle
@@ -357,6 +362,9 @@ prv_check_crc(lwgps_t* gh) {
     crc = (uint8_t)((CHTN(gh->p.term_str[0]) & 0x0F) << 0x04) | (CHTN(gh->p.term_str[1]) & 0x0F);   /* Convert received CRC from string (hex) to number */
     return gh->p.crc_calc == crc;               /* They must match! */
 }
+#else
+#define prv_check_crc(_gh)              (1)
+#endif /* LWGPS_CFG_CRC */
 
 /**
  * \brief           Copy temporary memory to user memory