route: add separate function to set netem qdisc delay distribution

A new function rtnl_netem_set_delay_distribution_data() has been added
to allow the user to pass the delay distribution directly without loading
it from a file.

In conjunction with the maketable code (see iproute2 / NISTnet) this can
be used to generate and load custom delay distributions on the fly.

2 files changed, 27 insertions, 10 deletions

diff --git a/include/netlink/route/qdisc/netem.h b/include/netlink/route/qdisc/netem.h
index 4b071bf..707d665 100644
--- a/include/netlink/route/qdisc/netem.h
+++ b/include/netlink/route/qdisc/netem.h
@@ -66,6 +66,7 @@ extern int rtnl_netem_get_delay_correlation(struct rtnl_qdisc *);
 /* Delay Distribution */
 #define MAXDIST 65536
 extern int rtnl_netem_set_delay_distribution(struct rtnl_qdisc *, const char *);
+extern int rtnl_netem_set_delay_distribution_data(struct rtnl_qdisc *, int16_t *, size_t len);
 extern int rtnl_netem_get_delay_distribution_size(struct rtnl_qdisc *);
 extern int rtnl_netem_get_delay_distribution(struct rtnl_qdisc *, int16_t **);
 
diff --git a/lib/route/qdisc/netem.c b/lib/route/qdisc/netem.c
index c4ba2a1..0df5b01 100644
--- a/lib/route/qdisc/netem.c
+++ b/lib/route/qdisc/netem.c
@@ -867,17 +867,36 @@ int rtnl_netem_get_delay_distribution(struct rtnl_qdisc *qdisc, int16_t **dist_p
 }
 
 /**
- * Set the delay distribution. Latency/jitter must be set before applying.
+ * Set the delay distribution data. Latency/jitter must be set before applying.
  * @arg qdisc Netem qdisc.
- * @arg dist_type The name of the distribution (type, file, path/file).
  * @return 0 on success, error code on failure.
  */
-int rtnl_netem_set_delay_distribution(struct rtnl_qdisc *qdisc, const char *dist_type) {
+int rtnl_netem_set_delay_distribution_data(struct rtnl_qdisc *qdisc, int16_t *data, size_t len) {
 	struct rtnl_netem *netem;
 
 	if (!(netem = rtnl_tc_data(TC_CAST(qdisc))))
 		BUG();
 
+	if (len > MAXDIST)
+		return -NLE_INVAL;
+
+	netem->qnm_dist.dist_data = (int16_t *) calloc(len, sizeof(int16_t));
+
+	memcpy(netem->qnm_dist.dist_data, data, len * sizeof(int16_t));
+
+	netem->qnm_dist.dist_size = len;
+	netem->qnm_mask |= SCH_NETEM_ATTR_DIST;
+
+	return 0;
+}
+
+/**
+ * Load the delay distribution from a file. Latency/jitter must be set before applying.
+ * @arg qdisc Netem qdisc.
+ * @arg dist_type The name of the distribution (type, file, path/file).
+ * @return 0 on success, error code on failure.
+ */
+int rtnl_netem_set_delay_distribution(struct rtnl_qdisc *qdisc, const char *dist_type) {
 	FILE *f;
 	int n = 0;
 	size_t i;
@@ -909,7 +928,7 @@ int rtnl_netem_set_delay_distribution(struct rtnl_qdisc *qdisc, const char *dist
 	if (f == NULL)
 		return -nl_syserr2nlerr(errno);
 
-	netem->qnm_dist.dist_data = (int16_t *) calloc (MAXDIST, sizeof(int16_t));
+	int16_t * data = (int16_t *) calloc (MAXDIST, sizeof(int16_t));
 
 	line = (char *) calloc (sizeof(char), len + 1);
 
@@ -928,17 +947,14 @@ int rtnl_netem_set_delay_distribution(struct rtnl_qdisc *qdisc, const char *dist
 				fclose(f);
 				return -NLE_INVAL;
 			}
-			netem->qnm_dist.dist_data[n++] = x;
+			data[n++] = x;
 		}
 	}
 
 	free(line);
-
-	netem->qnm_dist.dist_size = n;
-	netem->qnm_mask |= SCH_NETEM_ATTR_DIST;
-
 	fclose(f);
-	return 0;
+	
+	return rtnl_netem_set_delay_distribution_data(qdisc, data, n);
 }
 
 /** @} */