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, 174 insertions, 0 deletions

diff --git a/src/tools/cbr/cbr_server.c b/src/tools/cbr/cbr_server.c
new file mode 100644
index 00000000..14791bd4
--- /dev/null
+++ b/src/tools/cbr/cbr_server.c
@@ -0,0 +1,174 @@
+/*
+ * 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 <stdbool.h>
+#include <signal.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <pthread.h>
+
+#include <ouroboros/dev.h>
+#include <ouroboros/time_utils.h>
+
+#define DIF_NAME "*"
+
+
+void shutdown_server(int signo)
+{
+        char * dif = DIF_NAME;
+
+        if (ap_unreg(&dif, 1)) {
+                printf("Failed to unregister application.\n");
+                ap_fini();
+                exit(EXIT_FAILURE);
+        }
+
+        ap_fini();
+        exit(EXIT_SUCCESS);
+}
+
+void * handleflow(void * o)
+{
+        ssize_t count = 0;
+        int fd = *((int *) o);
+        char buf[BUF_SIZE];
+
+        struct timespec now;
+        struct timespec alive;
+        struct timespec intv = {server_settings.interval, 0};
+
+        struct timespec iv_start;
+        struct timespec iv_end;
+
+        bool stop = false;
+
+        long sdus            = 0;
+        long sdus_intv       = 0;
+        long bytes_read      = 0;
+        long bytes_read_intv = 0;
+
+
+        clock_gettime(CLOCK_REALTIME, &iv_start);
+        alive = iv_start;
+        ts_add(&iv_start, &intv, &iv_end);
+
+        flow_cntl(fd, FLOW_F_SETFL, FLOW_O_NONBLOCK);
+
+        while (!stop) {
+                clock_gettime(CLOCK_REALTIME, &now);
+
+                count = flow_read(fd, buf, BUF_SIZE);
+
+                if (count > 0) {
+                        clock_gettime(CLOCK_REALTIME, &alive);
+                        sdus++;
+                        bytes_read += count;
+                }
+
+                if (ts_diff_us(&alive, &now)
+                    > server_settings.timeout * MILLION) {
+                        printf("Test on flow %d timed out\n", fd);
+                        stop = true;
+                }
+
+                if (stop || ts_diff_ms(&now, &iv_end) < 0) {
+                        long us = ts_diff_us(&iv_start, &now);
+                        printf("Flow %4d: %9ld SDUs (%12ld bytes) in %9ld ms"
+                               " => %9.4f p/s, %9.4f Mb/s\n",
+                               fd,
+                               sdus-sdus_intv,
+                               bytes_read-bytes_read_intv,
+                               us / 1000,
+                               ((sdus-sdus_intv) / (float) us) * MILLION,
+                               8 * (bytes_read-bytes_read_intv)
+                               / (float)(us));
+                        iv_start=iv_end;
+                        sdus_intv = sdus;
+                        bytes_read_intv = bytes_read;
+                        ts_add(&iv_start, &intv, &iv_end);
+                }
+        }
+
+        return 0;
+}
+
+int server_main()
+{
+        int    server_fd = 0;
+        int    client_fd = 0;
+        char * dif = DIF_NAME;
+        char * client_name = NULL;
+        int    i         = 0;
+        pthread_t * threads = malloc(sizeof(*threads) * 10);
+        if (threads == NULL)
+                exit(1);
+
+        printf("Server started, interval is %ld s, timeout is %ld s.\n",
+               server_settings.interval, server_settings.timeout);
+
+        /* Manual cleanup is required for now */
+        if (signal(SIGINT, shutdown_server) == SIG_ERR) {
+                printf("Can't install signal handler.\n");
+                return -1;
+        }
+
+        if (ap_init(SERVER_AP_NAME)) {
+                printf("Failed to init AP.\n");
+                return -1;
+        }
+
+        server_fd = ap_reg(&dif, 1);
+        if (server_fd < 0) {
+                printf("Failed to register application.\n");
+                ap_fini();
+                return -1;
+        }
+
+        while (true) {
+                client_fd = flow_accept(server_fd,
+                                        &client_name, NULL);
+                if (client_fd < 0) {
+                        printf("Failed to accept flow.\n");
+                        break;
+                }
+
+                printf("New flow from %s.\n", client_name);
+
+                if (flow_alloc_resp(client_fd, 0)) {
+                        printf("Failed to give an allocate response.\n");
+                        flow_dealloc(client_fd);
+                        continue;
+                }
+
+                if (i < 10) {
+                        pthread_create(&threads[i++],
+                                       NULL,
+                                       handleflow,
+                                       &client_fd);
+                }
+        }
+
+        ap_fini();
+
+        return 0;
+}