--- /dev/null
+/**
+ * collectd - src/multicast.c
+ * Copyright (C) 2005 Florian octo Forster
+ *
+ * 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.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors:
+ * Florian octo Forster <octo at verplant.org>
+ **/
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <netdb.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <syslog.h>
+#include <errno.h>
+
+#include "multicast.h"
+#include "common.h"
+
+/*
+ * From RFC2365:
+ *
+ * The IPv4 Organization Local Scope -- 239.192.0.0/14
+ *
+ * 239.192.0.0/14 is defined to be the IPv4 Organization Local Scope, and is
+ * the space from which an organization should allocate sub-ranges when
+ * defining scopes for private use.
+ *
+ * Port 25826 is not assigned as of 2005-09-12
+ */
+
+#define MCAST_GROUP "239.192.74.66"
+#define UDP_PORT 25826
+
+/* 1500 - 40 - 8 = Ethernet packet - IPv6 header - UDP header */
+#define BUFF_SIZE 1452
+
+int get_read_socket (void)
+{
+ static int sd = -1; /* socket descriptor */
+ int optval;
+
+ struct sockaddr_in addr;
+ struct ip_mreq mreq;
+
+ if (sd != -1)
+ return (sd);
+
+ /* Create UDP sicket */
+ if ((sd = socket (PF_INET, SOCK_DGRAM, 0)) == -1)
+ {
+ syslog (LOG_ERR, "socket: %s", strerror (errno));
+ return (-1);
+ }
+
+ optval = 1;
+ if (setsockopt (sd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof(optval)) == -1)
+ {
+ syslog (LOG_ERR, "setsockopt: %s", strerror (errno));
+ shutdown (sd, SHUT_RD);
+ sd = -1;
+ return (-1);
+ }
+
+ memset (&addr, '\0', sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = htonl (INADDR_ANY);
+ addr.sin_port = htons (UDP_PORT);
+ if (bind (sd, (struct sockaddr *) &addr, sizeof (addr)) == -1)
+ {
+ syslog (LOG_ERR, "bind: %s", strerror (errno));
+ shutdown (sd, SHUT_RD);
+ sd = -1;
+ return (-1);
+ }
+
+ mreq.imr_multiaddr.s_addr = inet_addr (MCAST_GROUP);
+ mreq.imr_interface.s_addr = htonl (INADDR_ANY);
+ if (setsockopt (sd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof (mreq)) == -1)
+ {
+ syslog (LOG_ERR, "setsockopt: %s", strerror (errno));
+ shutdown (sd, SHUT_RD);
+ sd = -1;
+ return (-1);
+ }
+
+ return (sd);
+}
+
+int get_write_socket (void)
+{
+ static int sd = -1;
+
+ if (sd != -1)
+ return (sd);
+
+ if ((sd = socket (AF_INET, SOCK_DGRAM, 0)) == -1)
+ {
+ syslog (LOG_ERR, "socket: %s", strerror (errno));
+ return (-1);
+ }
+
+ return (sd);
+}
+
+char *addr_to_host (struct sockaddr_in *addr)
+{
+ char *host;
+ struct hostent *he;
+
+ if ((he = gethostbyaddr ((char *) &addr->sin_addr, sizeof (addr->sin_addr), AF_INET)) != NULL)
+ {
+ host = strdup (he->h_name);
+ }
+ else
+ {
+ char *tmp = inet_ntoa (addr->sin_addr);
+ host = strdup (tmp);
+ }
+
+ return (host);
+}
+
+int multicast_receive (char **host, char **type, char **instance, char **value)
+{
+ int sd = get_read_socket ();
+
+ char buffer[BUFF_SIZE];
+
+ struct sockaddr_in addr;
+ socklen_t addr_size;
+
+ char *fields[4];
+
+ *host = NULL;
+ *type = NULL;
+ *instance = NULL;
+ *value = NULL;
+
+ if (sd == -1)
+ return (-1);
+
+ addr_size = sizeof (addr);
+
+ if (recvfrom (sd, buffer, BUFF_SIZE, 0, (struct sockaddr *) &addr, &addr_size) == -1)
+ {
+ syslog (LOG_ERR, "recvfrom: %s", strerror (errno));
+ return (-1);
+ }
+
+ if (strsplit (buffer, fields, 4) != 3)
+ return (-1);
+
+ *host = addr_to_host (&addr);
+ *type = strdup (fields[0]);
+ *instance = strdup (fields[1]);
+ *value = strdup (fields[2]);
+
+ if (*host == NULL || *type == NULL || *instance == NULL || *value == NULL)
+ return (-1);
+
+ return (0);
+}
+
+int multicast_send (char *type, char *instance, char *value)
+{
+ int sd = get_write_socket ();
+ struct sockaddr_in addr;
+
+ char buf[BUFF_SIZE];
+ int buflen;
+
+ if (sd == -1)
+ return (-1);
+
+ if ((buflen = snprintf (buf, BUFF_SIZE, "%s %s %s", type, instance, value)) >= BUFF_SIZE)
+ {
+ syslog (LOG_WARNING, "multicast_send: Output truncated..");
+ return (-1);
+ }
+ buf[buflen++] = '\0';
+
+ memset(&addr, '\0', sizeof (addr));
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = inet_addr (MCAST_GROUP);
+ addr.sin_port = htons (UDP_PORT);
+
+ return (sendto (sd, buf, buflen, 0, (struct sockaddr *) &addr, sizeof (addr)));
+}
--- /dev/null
+/**
+ * collectd - src/multicast.h
+ * Copyright (C) 2005 Florian octo Forster
+ *
+ * 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.,
+ * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Authors:
+ * Florian octo Forster <octo at verplant.org>
+ **/
+
+#ifndef MULTICAST_H
+#define MULTICAST_H
+
+int multicast_receive (char **host, char **type, char **instance, char **value);
+int multicast_send (char *type, char *instance, char *value);
+
+#endif /* MULTICAST_H */
projects / collectd.git / commitdiff