tools, lib: cbr tool for bandwidth testing

The tool sends constant bandwidth traffic between a client and a
server. cbr --help for more info.

Adds time_utils.h to the library containing useful functions for
arithmetic with timespec and timeval structures.

1 files changed, 97 insertions, 0 deletions

diff --git a/src/tools/cbr/cbr_client.c b/src/tools/cbr/cbr_client.c
new file mode 100644
index 00000000..7b8e8b3f
--- /dev/null
+++ b/src/tools/cbr/cbr_client.c
@@ -0,0 +1,97 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * A simple CBR generator
+ *
+ *    Dimitri Staessens <dimitri.staessens@intec.ugent.be>
+ *    Sander Vrijders <sander.vrijders@intec.ugent.be>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <ouroboros/dev.h>
+#include <ouroboros/time_utils.h>
+
+int client_main(int duration, int size, long rate)
+{
+        int fd = 0;
+        int result = 0;
+        bool stop = false;
+        char buf[size];
+        long seqnr = 0;
+        long long gap = size * 8 * (BILLION / rate); /* ns */
+
+        struct timespec start;
+        struct timespec end;
+        struct timespec interval = {(gap / BILLION), gap % BILLION};
+        int ms;
+
+        if (ap_init(CLIENT_AP_NAME)) {
+                printf("Failed to init AP.\n");
+                return -1;
+        }
+
+        printf("Client started, duration %d, rate %lu b/s, size %d B.\n",
+                duration, rate, size);
+
+        fd = flow_alloc(SERVER_AP_NAME, NULL, NULL);
+        if (fd < 0) {
+                printf("Failed to allocate flow.\n");
+                ap_fini();
+                return -1;
+        }
+
+        result = flow_alloc_res(fd);
+        if (result < 0) {
+                printf("Flow allocation refused.\n");
+                flow_dealloc(fd);
+                ap_fini();
+                return -1;
+        }
+
+        clock_gettime(CLOCK_REALTIME, &start);
+        while (!stop) {
+                memcpy(buf, &seqnr, sizeof(seqnr));
+
+                if (flow_write(fd, buf, size) == -1) {
+                        printf("Failed to write SDU.\n");
+                        stop = true;
+                }
+
+                nanosleep(&interval, NULL);
+
+                seqnr++;
+
+                clock_gettime(CLOCK_REALTIME, &end);
+
+                if (duration != 0
+                    && ts_diff_us(&start, &end) / MILLION >= (long) duration)
+                        stop = 1;
+        }
+
+        clock_gettime(CLOCK_REALTIME, &end);
+
+        ms = ts_diff_ms(&start, &end);
+
+        printf("sent statistics: "
+               "%9ld SDUs, %12ld bytes in %9d ms, %4.4f Mb/s\n",
+               seqnr, seqnr * size, ms, (seqnr * size * 8.0)/(ms * 1000));
+
+        flow_dealloc(fd);
+
+        ap_fini();
+
+        return 0;
+}