Implement DLTClient for UDP multicast (#240)

* Add UDP multicast support on client side

UDP multicast support is already present on server side. This
patch add seemless support for UDP multicast on client side
in dlt-receive.

Signed-off-by: Joao Sousa <joao.sa.sousa@ctw.bmwgroup.com>

4 files changed, 113 insertions, 7 deletions

diff --git a/src/console/dlt-receive.c b/src/console/dlt-receive.c
index 24280ee..cdfa274 100644
--- a/src/console/dlt-receive.c
+++ b/src/console/dlt-receive.c
@@ -96,6 +96,7 @@ typedef struct {
     int mflag;
     int vflag;
     int yflag;
+    int uflag;
     char *ovalue;
     char *ovaluebase; /* ovalue without ".dlt" */
     char *fvalue;
@@ -131,6 +132,7 @@ void usage()
     printf("  -v            Verbose mode\n");
     printf("  -h            Usage\n");
     printf("  -y            Serial device mode\n");
+    printf("  -u            UDP multicast mode\n");
     printf("  -b baudrate   Serial device baudrate (Default: 115200)\n");
     printf("  -e ecuid      Set ECU ID (Default: RECV)\n");
     printf("  -o filename   Output messages in new DLT file\n");
@@ -300,6 +302,7 @@ int main(int argc, char *argv[])
     dltdata.mflag = 0;
     dltdata.vflag = 0;
     dltdata.yflag = 0;
+    dltdata.uflag = 0;
     dltdata.ovalue = 0;
     dltdata.ovaluebase = 0;
     dltdata.fvalue = 0;
@@ -313,7 +316,7 @@ int main(int argc, char *argv[])
     /* Fetch command line arguments */
     opterr = 0;
 
-    while ((c = getopt (argc, argv, "vashyxmf:o:e:b:c:")) != -1)
+    while ((c = getopt (argc, argv, "vashyuxmf:o:e:b:c:")) != -1)
         switch (c) {
         case 'v':
         {
@@ -350,6 +353,11 @@ int main(int argc, char *argv[])
             dltdata.yflag = 1;
             break;
         }
+        case 'u':
+        {
+            dltdata.uflag = 1;
+            break;
+        }
         case 'f':
         {
             dltdata.fvalue = optarg;
@@ -425,9 +433,14 @@ int main(int argc, char *argv[])
     dlt_client_register_message_callback(dlt_receive_message_callback);
 
     /* Setup DLT Client structure */
-    dltclient.mode = dltdata.yflag;
+    if(dltdata.uflag) {
+        dltclient.mode = DLT_CLIENT_MODE_UDP_MULTICAST;
+    }
+    else {
+        dltclient.mode = dltdata.yflag;
+    }
 
-    if (dltclient.mode == DLT_CLIENT_MODE_TCP) {
+    if (dltclient.mode == DLT_CLIENT_MODE_TCP || dltclient.mode == DLT_CLIENT_MODE_UDP_MULTICAST) {
         for (index = optind; index < argc; index++)
             if (dlt_client_set_server_ip(&dltclient, argv[index]) == -1) {
                 fprintf(stderr, "set server ip didn't succeed\n");
diff --git a/src/examples/CMakeLists.txt b/src/examples/CMakeLists.txt
index 93f76a8..013700d 100644
--- a/src/examples/CMakeLists.txt
+++ b/src/examples/CMakeLists.txt
@@ -40,8 +40,8 @@ if(WITH_UDP_CONNECTION)
     set_target_properties(dlt-example-multicast-clientmsg-view PROPERTIES LINKER_LANGUAGE C)
 
     install(TARGETS dlt-example-multicast-clientmsg-view
-			RUNTIME DESTINATION bin
-			COMPONENT base)
+            RUNTIME DESTINATION bin
+            COMPONENT base)
 
 endif(WITH_UDP_CONNECTION)
 
diff --git a/src/lib/dlt_client.c b/src/lib/dlt_client.c
index 5c18c0e..0b44d6e 100644
--- a/src/lib/dlt_client.c
+++ b/src/lib/dlt_client.c
@@ -121,6 +121,7 @@ DltReturnValue dlt_client_init_port(DltClient *client, int port, int verbose)
     client->receiver.buffer = NULL;
     client->receiver.buf = NULL;
     client->receiver.backup_buf = NULL;
+    client->hostip = NULL;
 
     return DLT_RETURN_OK;
 }
@@ -153,16 +154,17 @@ DltReturnValue dlt_client_init(DltClient *client, int verbose)
         dlt_vlog(LOG_INFO,
                  "Init dlt client struct with default port: %hu.\n",
                  servPort);
-
     return dlt_client_init_port(client, servPort, verbose);
 }
 
 DltReturnValue dlt_client_connect(DltClient *client, int verbose)
 {
+    const int yes = 1;
     char portnumbuffer[33];
     struct addrinfo hints, *servinfo, *p;
     struct sockaddr_un addr;
     int rv;
+    struct ip_mreq mreq;
     memset(&hints, 0, sizeof(hints));
     hints.ai_socktype = SOCK_STREAM;
 
@@ -266,6 +268,58 @@ DltReturnValue dlt_client_connect(DltClient *client, int verbose)
         }
 
         break;
+    case DLT_CLIENT_MODE_UDP_MULTICAST:
+
+        if ((client->sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
+        {
+            fprintf(stderr, "ERROR: socket error: %s\n", strerror(errno));
+            return DLT_RETURN_ERROR;
+        }
+
+        /* allow multiple sockets to use the same PORT number */
+        if (setsockopt(client->sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0)
+        {
+            fprintf(stderr, "ERROR: Reusing address failed: %s\n", strerror(errno));
+            return DLT_RETURN_ERROR;
+        }
+
+        memset(&client->receiver.addr, 0, sizeof(client->receiver.addr));
+        client->receiver.addr.sin_family = AF_INET;
+        client->receiver.addr.sin_addr.s_addr = htonl(INADDR_ANY);
+        client->receiver.addr.sin_port = htons(client->port);
+
+        /* bind to receive address */
+        if (bind(client->sock, (struct sockaddr*) &client->receiver.addr, sizeof(client->receiver.addr)) < 0)
+        {
+            fprintf(stderr, "ERROR: bind failed: %s\n", strerror(errno));
+            return DLT_RETURN_ERROR;
+        }
+
+        mreq.imr_interface.s_addr = htonl(INADDR_ANY);
+        if (client->hostip)
+        {
+            mreq.imr_interface.s_addr = inet_addr(client->hostip);
+        }
+        if (client->servIP == NULL)
+        {
+            fprintf(stderr, "ERROR: server address not set\n");
+            return DLT_RETURN_ERROR;
+        }
+
+        mreq.imr_multiaddr.s_addr = inet_addr(client->servIP);
+        if (mreq.imr_multiaddr.s_addr == (in_addr_t)-1)
+        {
+            fprintf(stderr, "ERROR: server address not not valid %s\n", client->servIP);
+            return DLT_RETURN_ERROR;
+        }
+
+        if (setsockopt(client->sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, (char *)&mreq, sizeof(mreq)) < 0)
+        {
+            fprintf(stderr, "ERROR: setsockopt add membership failed: %s\n", strerror(errno));
+            return DLT_RETURN_ERROR;
+        }
+
+        break;
     default:
 
         if (verbose)
@@ -315,6 +369,10 @@ DltReturnValue dlt_client_cleanup(DltClient *client, int verbose)
         client->socketPath = NULL;
     }
 
+    if (client->hostip) {
+        free(client->hostip);
+        client->hostip = NULL;
+    }
     return ret;
 }
 
@@ -875,6 +933,16 @@ DltReturnValue dlt_client_setbaudrate(DltClient *client, int baudrate)
     return DLT_RETURN_OK;
 }
 
+DltReturnValue dlt_client_set_mode(DltClient *client, DltClientMode mode)
+{
+    if (client == 0)
+        return DLT_RETURN_ERROR;
+
+    client->mode = mode;
+    return DLT_RETURN_OK;
+
+}
+
 int dlt_client_set_server_ip(DltClient *client, char *ipaddr)
 {
     client->servIP = strdup(ipaddr);
@@ -887,6 +955,18 @@ int dlt_client_set_server_ip(DltClient *client, char *ipaddr)
     return DLT_RETURN_OK;
 }
 
+int dlt_client_set_host_if_address(DltClient *client, char *hostip)
+{
+    client->hostip = strdup(hostip);
+
+    if (client->hostip == NULL) {
+        dlt_log(LOG_ERR, "ERROR: failed to duplicate UDP interface address\n");
+        return DLT_RETURN_ERROR;
+    }
+
+    return DLT_RETURN_OK;
+}
+
 int dlt_client_set_serial_device(DltClient *client, char *serial_device)
 {
     client->serialDevice = strdup(serial_device);
diff --git a/src/shared/dlt_common.c b/src/shared/dlt_common.c
index eb620f5..823bca7 100644
--- a/src/shared/dlt_common.c
+++ b/src/shared/dlt_common.c
@@ -2014,6 +2014,8 @@ DltReturnValue dlt_receiver_free_unix_socket(DltReceiver *receiver)
 
 int dlt_receiver_receive(DltReceiver *receiver, DltReceiverType from_src)
 {
+    socklen_t addrlen;
+
     if (receiver == NULL)
         return -1;
 
@@ -2035,12 +2037,23 @@ int dlt_receiver_receive(DltReceiver *receiver, DltReceiverType from_src)
                                    receiver->buf + receiver->lastBytesRcvd,
                                    receiver->buffersize - receiver->lastBytesRcvd,
                                    0);
-    else
+    else if (from_src == DLT_RECEIVE_FD)
         /* wait for data from fd */
         receiver->bytesRcvd = read(receiver->fd,
                                    receiver->buf + receiver->lastBytesRcvd,
                                    receiver->buffersize - receiver->lastBytesRcvd);
 
+    else {
+        /* wait for data from UDP socket */
+        addrlen = sizeof(receiver->addr);
+        receiver->bytesRcvd = recvfrom(receiver->fd,
+                                       receiver->buf + receiver->lastBytesRcvd,
+                                       receiver->buffersize - receiver->lastBytesRcvd,
+                                       0,
+                                       (struct sockaddr *)&(receiver->addr),
+                                       &addrlen);
+    }
+
     if (receiver->bytesRcvd <= 0) {
         receiver->bytesRcvd = 0;