[lib] Use clock_gettime() instead of gettimeofday()

Abandon the old struct timeval and gettimeofday(). We now use the new
struct timespec and clock_gettime().
struct timespec has a nanosecond resolution, but we lower the resolution
to keep only milliseconds. The code is inspired from the Timestamp class
of the owlps-positioning.

TODO

@@ -1,4 +1 @@
-Abandonner gettimeofday() et struct timeval au profit de clock_gettime()
-et struct timespec. gettimeofday() est obsolète depuis POSIX:2008.
-
 Abandonner int, long & Cie pour les échanges de données, passer à stdint.h

infrastructure-centred/owlps-client/Makefile

@@ -25,7 +25,7 @@ DEPFLAGS = -MMD
 XCFLAGS = $(CFLAGS) $(DEPFLAGS) $(WARN) $(HEADERS)
 PICFLAG = -fPIC
 LIBS = -L../../libowlps -lowlps -L../libowlps-client -lowlps-client
-STATIC_LIBS = -liw -lm
+STATIC_LIBS = -liw -lm -lrt
 
 
 ## Cibles de compilation standard ##

infrastructure-centred/owlps-listener/owlps-listenerd.c

@@ -629,7 +629,8 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
     return ;
 
   memcpy(couple.ap_mac_addr_bytes, my_mac, 6) ; // Copy AP MAC
-  couple.start_time = header->ts ; // Capture time is in the pcap header
+  // Capture time is in the pcap header:
+  couple.start_time = timeval_to_timestamp(header->ts) ;
   // Transmission time on the mobile is unknown (unless the packet is
   // an explicit request):
   bzero(&couple.request_time, sizeof(TIMESTAMP)) ;

libowlps/Makefile

@@ -38,7 +38,7 @@ CFLAGS=-O2 -Wall -Wextra -Wstrict-prototypes -O -I.
 DEPFLAGS=-MMD
 XCFLAGS=$(CFLAGS) $(DEPFLAGS) $(WARN) $(HEADERS)
 PICFLAG=-fPIC
-LIBS=-liw
+LIBS = -liw -lrt
 #STRIPFLAGS= -Wl,-s
 #LDFLAGS=
 

libowlps/Makefile_atheros

@@ -38,7 +38,7 @@ CFLAGS=-O2 -Wall -Wextra -Wstrict-prototypes -O -I.
 DEPFLAGS=-MMD
 XCFLAGS=$(CFLAGS) $(DEPFLAGS) $(WARN) $(HEADERS)
 PICFLAG=-fPIC
-LIBS=-liw
+LIBS = -liw -lrt
 #STRIPFLAGS= -Wl,-s
 #LDFLAGS=
 LATHEROS=-L$(TOOLCHAIN)/mips/usr/lib/

libowlps/libowlps.c

@@ -91,12 +91,50 @@ char frequency_to_channel(unsigned short channel)
 
 
 /*
- * Set the TIMESTAMP 'now' at the current time.
+ * Set the TIMESTAMP 'now' at the current time (millisecond-precision).
  */
 void timestamp_now(TIMESTAMP *now)
 {
-  if (gettimeofday(now, NULL))
-    perror("Cannot get the current time") ;
+  if (timestamp_now_ns(now))
+    timestamp_round_to_ms(now) ;
+}
+
+
+
+/*
+ * Set the TIMESTAMP 'now' at the current time (nanosecond-precision).
+ */
+BOOL timestamp_now_ns(TIMESTAMP *now)
+{
+  if (clock_gettime(CLOCK_REALTIME, now))
+    {
+      perror("Cannot get the current time") ;
+      return FALSE ;
+    }
+  return TRUE ;
+}
+
+
+
+/*
+ * Lower the precision of 'now' to milliseconds.
+ */
+void timestamp_round_to_ms(TIMESTAMP *now)
+{
+  now->tv_nsec = now->tv_nsec / 1000000 * 1000000 ;
+}
+
+
+
+/*
+ * Returns a TIMESTAMP from a struct timeval.
+ */
+TIMESTAMP timeval_to_timestamp(const struct timeval d)
+{
+  TIMESTAMP res ;
+  res.tv_sec = d.tv_sec ;
+  res.tv_nsec = d.tv_usec * 1000 ;
+  return res ;
 }
 
 
@@ -106,25 +144,11 @@ void timestamp_now(TIMESTAMP *now)
  */
 unsigned long long timestamp_to_ms(TIMESTAMP d)
 {
-  return d.tv_sec * 1000 + d.tv_usec / 1000 ;
+  return d.tv_sec * 1000 + d.tv_nsec / 1000000 ;
 }
 
 
 
-/*
- * Converts a date value in milliseconds into a TIMESTAMP.
- *
-TIMESTAMP ms_to_timestamp(unsigned long long tms)
-{
-  TIMESTAMP d ;
-  d.tv_sec = tms / 1000 ;
-  d.tv_usec = (tms - d.tv_sec * 1000) * 1000 ;
-  return d ;
-}
-*/
-
-
-
 /*
  * Returns the time (in milliseconds) between two dates.
  */

libowlps/owlps.h

@@ -13,7 +13,6 @@
 
 #include <pthread.h>
 
-#include <sys/time.h>
 #include <time.h>
 
 #include <sys/types.h>
@@ -61,7 +60,7 @@ typedef enum {NORTH = 1, EAST, SOUTH, WEST} DIRECTION ;
 
 
 /* Timestamp type */
-typedef struct timeval TIMESTAMP ;
+typedef struct timespec TIMESTAMP ;
 
 
 /* Message sent by the listener to the aggregator */
@@ -224,6 +223,9 @@ char frequency_to_channel(unsigned short channel) ;
 
 // Time
 void timestamp_now(TIMESTAMP *now) ;
+BOOL timestamp_now_ns(TIMESTAMP *now) ;
+void timestamp_round_to_ms(TIMESTAMP *now) ;
+TIMESTAMP timeval_to_timestamp(const struct timeval d) ;
 unsigned long long timestamp_to_ms(TIMESTAMP date) ;
 unsigned long time_elapsed(TIMESTAMP sup, TIMESTAMP inf) ;