[2/2] alfred: Adding time_subtract utility function

Message ID 1472157024-17530-2-git-send-email-jhaws@sdl.usu.edu
State Superseded, archived
Headers

Commit Message

Jonathan Haws Aug. 25, 2016, 8:30 p.m. UTC
  Signed-off-by: Jonathan Haws <jhaws@sdl.usu.edu>

Added time_subtract() utility function to use for simply subtracting
one timespec from another.
---
 alfred.h |  2 ++
 server.c |  5 ++++-
 util.c   | 13 +++++++++++++
 3 files changed, 19 insertions(+), 1 deletion(-)
  

Comments

Jonathan Haws Aug. 25, 2016, 8:37 p.m. UTC | #1
On Thu, 2016-08-25 at 14:30 -0600, Jonathan Haws wrote:
> Signed-off-by: Jonathan Haws <jhaws@sdl.usu.edu>

> 

> Added time_subtract() utility function to use for simply subtracting

> one timespec from another.

> ---

>  alfred.h |  2 ++

>  server.c |  5 ++++-

>  util.c   | 13 +++++++++++++

>  3 files changed, 19 insertions(+), 1 deletion(-)

> 

> diff --git a/alfred.h b/alfred.h

> index 5b7e965..9d5f1e8 100644

> --- a/alfred.h

> +++ b/alfred.h

> @@ -196,6 +196,8 @@ int netsock_own_address(const struct globals

> *globals,

>  /* util.c */

>  int time_diff(struct timespec *tv1, struct timespec *tv2,

>  	      struct timespec *tvdiff);

> +int time_subtract(struct timespec *tv1, struct timespec *tv2,

> +	      struct timespec *tvout);

>  void time_random_seed(void);

>  uint16_t get_random_id(void);

>  bool is_valid_ether_addr(uint8_t *addr);

> diff --git a/server.c b/server.c

> index c5df945..884a1a7 100644

> --- a/server.c

> +++ b/server.c

> @@ -372,7 +372,10 @@ int alfred_server(struct globals *globals)

>  

>  	while (1) {

>  		clock_gettime(CLOCK_MONOTONIC, &now);

> -		time_diff(&now, &globals->sync_period, &now);

> +

> +		/* subtract the synchronization period from the

> current time */

> +		time_subtract(&now, &globals->sync_period, &now);

> +

>  		if (!time_diff(&last_check, &now, &tv)) {

>  			tv.tv_sec = 0;

>  			tv.tv_nsec = 0;

> diff --git a/util.c b/util.c

> index c7e11cc..1b67f78 100644

> --- a/util.c

> +++ b/util.c

> @@ -41,6 +41,19 @@ int time_diff(struct timespec *tv1, struct

> timespec *tv2,

>  	return (tvdiff->tv_sec >= 0);

>  }

>  

> +void time_subtract(struct timespec *tv1, struct timespec *tv2,

> +	      struct timespec *tvout) {

> +	tvout->tv_sec = tv1->tv_sec - tv2->tv_sec;

> +	if (tv1->tv_nsec < tv2->tv_nsec) {

> +		tvout->tv_nsec = 1000000000 + tv1->tv_nsec - tv2-

> >tv_nsec;

> +		tvout->tv_sec -= 1;

> +	} else {

> +		tvout->tv_nsec = tv1->tv_nsec - tv2->tv_nsec;

> +	}

> +

> +	return;

> +}

> +

>  void time_random_seed(void)

>  {

>  	struct timespec now;



Just ignore this patch for now - will submit new set.  Accidentally
sent this before it was ready....
  

Patch

diff --git a/alfred.h b/alfred.h
index 5b7e965..9d5f1e8 100644
--- a/alfred.h
+++ b/alfred.h
@@ -196,6 +196,8 @@  int netsock_own_address(const struct globals *globals,
 /* util.c */
 int time_diff(struct timespec *tv1, struct timespec *tv2,
 	      struct timespec *tvdiff);
+int time_subtract(struct timespec *tv1, struct timespec *tv2,
+	      struct timespec *tvout);
 void time_random_seed(void);
 uint16_t get_random_id(void);
 bool is_valid_ether_addr(uint8_t *addr);
diff --git a/server.c b/server.c
index c5df945..884a1a7 100644
--- a/server.c
+++ b/server.c
@@ -372,7 +372,10 @@  int alfred_server(struct globals *globals)
 
 	while (1) {
 		clock_gettime(CLOCK_MONOTONIC, &now);
-		time_diff(&now, &globals->sync_period, &now);
+
+		/* subtract the synchronization period from the current time */
+		time_subtract(&now, &globals->sync_period, &now);
+
 		if (!time_diff(&last_check, &now, &tv)) {
 			tv.tv_sec = 0;
 			tv.tv_nsec = 0;
diff --git a/util.c b/util.c
index c7e11cc..1b67f78 100644
--- a/util.c
+++ b/util.c
@@ -41,6 +41,19 @@  int time_diff(struct timespec *tv1, struct timespec *tv2,
 	return (tvdiff->tv_sec >= 0);
 }
 
+void time_subtract(struct timespec *tv1, struct timespec *tv2,
+	      struct timespec *tvout) {
+	tvout->tv_sec = tv1->tv_sec - tv2->tv_sec;
+	if (tv1->tv_nsec < tv2->tv_nsec) {
+		tvout->tv_nsec = 1000000000 + tv1->tv_nsec - tv2->tv_nsec;
+		tvout->tv_sec -= 1;
+	} else {
+		tvout->tv_nsec = tv1->tv_nsec - tv2->tv_nsec;
+	}
+
+	return;
+}
+
 void time_random_seed(void)
 {
 	struct timespec now;