netflow: Break out code for sending packets into a new "collectors" module.

sFlow uses a similar UDP structure so this will allow use to reuse the
NetFlow code for it.

1 files changed, 123 insertions, 0 deletions

diff --git a/ofproto/collectors.c b/ofproto/collectors.c
new file mode 100644
index 000000000..f7cb1dbe4
--- /dev/null
+++ b/ofproto/collectors.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2008, 2009 Nicira Networks.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include "collectors.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "socket-util.h"
+#include "svec.h"
+#include "util.h"
+
+#define THIS_MODULE VLM_collectors
+#include "vlog.h"
+
+struct collectors {
+    int *fds;                     /* Sockets. */
+    size_t n_fds;                 /* Number of sockets. */
+};
+
+/* Opens the targets specified in 'targets' for sending UDP packets.  This is
+ * useful for e.g. sending NetFlow or sFlow packets.  Returns 0 if successful,
+ * otherwise a positive errno value if opening at least one collector failed.
+ *
+ * Each target in 'targets' should be a string in the format "<host>[:<port>]".
+ * <port> may be omitted if 'default_port' is nonzero, in which case it
+ * defaults to 'default_port'.
+ *
+ * '*collectorsp' is set to a null pointer if no targets were successfully
+ * added, otherwise to a new collectors object if at least one was successfully
+ * added.  Thus, even on a failure return, it is possible that '*collectorsp'
+ * is nonnull, and even on a successful return, it is possible that
+ * '*collectorsp' is null, if 'target's is an empty svec. */
+int
+collectors_create(const struct svec *targets_, uint16_t default_port,
+                  struct collectors **collectorsp)
+{
+    struct collectors *c;
+    struct svec targets;
+    int retval = 0;
+    size_t i;
+
+    svec_clone(&targets, targets_);
+    svec_sort_unique(&targets);
+
+    c = xmalloc(sizeof *c);
+    c->fds = xmalloc(sizeof *c->fds * targets.n);
+    c->n_fds = 0;
+    for (i = 0; i < targets.n; i++) {
+        const char *name = targets.names[i];
+        int error;
+        int fd;
+
+        error = inet_open_active(SOCK_DGRAM, name, default_port, NULL, &fd);
+        if (fd >= 0) {
+            c->fds[c->n_fds++] = fd;
+        } else {
+            static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+
+            VLOG_WARN_RL(&rl, "couldn't open connection to collector %s (%s)",
+                         name, strerror(error));
+            if (!retval) {
+                retval = error;
+            }
+        }
+    }
+    svec_destroy(&targets);
+
+    if (c->n_fds) {
+        *collectorsp = c;
+    } else {
+        collectors_destroy(c);
+        *collectorsp = NULL;
+    }
+
+    return retval;
+}
+
+/* Destroys 'c'. */
+void
+collectors_destroy(struct collectors *c)
+{
+    if (c) {
+        size_t i;
+
+        for (i = 0; i < c->n_fds; i++) {
+            close(c->fds[i]);
+        }
+        free(c->fds);
+        free(c);
+    }
+}
+
+/* Sends the 'n'-byte 'payload' to each of the collectors in 'c'. */
+void
+collectors_send(const struct collectors *c, const void *payload, size_t n)
+{
+    size_t i;
+
+    for (i = 0; i < c->n_fds; i++) {
+        static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+        if (send(c->fds[i], payload, n, 0) == -1) {
+            VLOG_WARN_RL(&rl, "sending to collector failed: %s",
+                         strerror(errno));
+        }
+    }
+}