time resolution in microseconds

rtl_wmbus.c

@@ -32,15 +32,8 @@
 #include <stdio.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <string.h>
 #include <fixedptc/fixedptc.h>
-#include "build/version.h"
-#include "fir.h"
-#include "iir.h"
-#include "ppf.h"
-#include "moving_average_filter.h"
-#include "atan2.h"
-#include "t1_c1_packet_decoder.h"
-#include "s1_packet_decoder.h"
 
 #if defined(WIN32) || defined(_WIN32) || defined(WIN64) || defined(_WIN64)
 #define WINDOWS_BUILD 1
@@ -48,6 +41,16 @@
 #define WINDOWS_BUILD 0
 #endif
 
+#include "build/version.h"
+#include "fir.h"
+#include "iir.h"
+#include "ppf.h"
+#include "moving_average_filter.h"
+#include "atan2.h"
+#include "rtl_wmbus_util.h"
+#include "t1_c1_packet_decoder.h"
+#include "s1_packet_decoder.h"
+
 #if WINDOWS_BUILD == 1
 #define CHECK_FLOW 0
 
@@ -867,6 +870,7 @@ static void print_usage(const char *program_name)
 {
     fprintf(stdout, "rtl_wmbus: " VERSION "\n\n");
     fprintf(stdout, "Usage %s:\n", program_name);
+    fprintf(stdout, "\t-o remove DC offset\n");
     fprintf(stdout, "\t-a accelerate (use an inaccurate atan version)\n");
     fprintf(stdout, "\t-r 0 to disable run length algorithm\n");
     fprintf(stdout, "\t-t 0 to disable time2 algorithm\n");

rtl_wmbus.vpj

@@ -323,6 +323,9 @@
 			<F N="include/mode_s_util.h"/>
 			<F N="include/mode_t_util.h"/>
 		</Folder>
+		<Folder Name="samples">
+			<F N="samples/readme.txt"/>
+		</Folder>
 		<F N="androidbuild.bat"/>
 		<F N="atan2.h"/>
 		<F N="build-deb.sh"/>
@@ -335,6 +338,7 @@
 		<F N="README.md"/>
 		<F N="rtl_wmbus.c"/>
 		<F N="rtl_wmbus.py"/>
+		<F N="rtl_wmbus_util.h"/>
 		<F N="s1_packet_decoder.h"/>
 		<F N="t1_c1_packet_decoder.h"/>
 	</Files>

rtl_wmbus_util.h

@@ -0,0 +1,39 @@
+#include <stddef.h>
+#include <time.h>
+
+#if WINDOWS_BUILD
+#else
+#include <sys/time.h>
+#endif
+
+
+inline int make_time_string(char* timestamp, size_t timestamp_size)
+{
+  memset(timestamp, 0, timestamp_size);
+
+#if WINDOWS_BUILD
+  time_t now;
+  if (time(&now) == NULL)
+	return -1;
+
+  struct tm* timeinfo = gmtime(&now);
+  if (timeinfo == NULL)
+	return -1;
+
+  strftime(timestamp, timestamp_size, "%Y-%m-%d %H:%M:%S.000000", timeinfo);
+#else
+  struct timeval tv;
+  if (gettimeofday(&tv, NULL) != 0)
+	return -1;
+
+  struct tm timeinfo;
+  if (localtime_r(&tv.tv_sec, &timeinfo) == NULL)
+	return -1;
+
+  char fmt[timestamp_size];
+  strftime(fmt, sizeof(fmt), "%Y-%m-%d %H:%M:%S.%%06u", &timeinfo);
+  snprintf(timestamp, timestamp_size, fmt, tv.tv_usec);
+#endif
+
+  return 0;
+}

s1_packet_decoder.h

@@ -31,7 +31,6 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
-#include <time.h>
 
 static const uint8_t MANCHESTER_IEEE_802_3[4] = {
     0xFF, 0x01, 0x00, 0xFF // According to wireless MBus spec.: "01b” representing a “one”; "10b" representing a "zero".
@@ -227,11 +226,7 @@ static void s1_rx_last_data_bit(unsigned bit, struct s1_packet_decoder_work *dec
     }
     else
     {
-        time_t now;
+        make_time_string(decoder->timestamp, sizeof(decoder->timestamp));
-        time(&now);
-
-        struct tm *timeinfo = gmtime(&now);
-        strftime(decoder->timestamp, sizeof(decoder->timestamp), "%Y-%m-%d %H:%M:%S.000", timeinfo);
     }
 }
 

t1_c1_packet_decoder.h

@@ -31,7 +31,6 @@
 #include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
-#include <time.h>
 
 #if !defined(PACKET_CAPTURE_THRESHOLD)
 #define PACKET_CAPTURE_THRESHOLD  5u
@@ -388,11 +387,7 @@ static void t1_rx_low_nibble_last_data_bit(unsigned bit, struct t1_c1_packet_dec
     }
     else
     {
-        time_t now;
+        make_time_string(decoder->timestamp, sizeof(decoder->timestamp));
-        time(&now);
-
-        struct tm *timeinfo = gmtime(&now);
-        strftime(decoder->timestamp, sizeof(decoder->timestamp), "%Y-%m-%d %H:%M:%S.000", timeinfo);
     }
 }
 
@@ -460,11 +455,7 @@ static void c1_rx_last_data_bit(unsigned bit, struct t1_c1_packet_decoder_work *
     }
     else
     {
-        time_t now;
+        make_time_string(decoder->timestamp, sizeof(decoder->timestamp));
-        time(&now);
-
-        struct tm *timeinfo = gmtime(&now);
-        strftime(decoder->timestamp, sizeof(decoder->timestamp), "%Y-%m-%d %H:%M:%S.000", timeinfo);
     }
 }