create a net_ namespace for gpsd-as-a-client protocols. currently these are

dgpsip and ntrip. eventually, gpsd will be able to connect to a remote gpsd.

1 files changed, 103 insertions, 0 deletions

diff --git a/net_gnss_dispatch.c b/net_gnss_dispatch.c
new file mode 100644
index 00000000..b2ca450e
--- /dev/null
+++ b/net_gnss_dispatch.c
@@ -0,0 +1,103 @@
+/* $Id$ */
+/* dgnss.c -- common interface to a number of Differential GNSS services */
+
+#include <sys/types.h>
+#ifndef S_SPLINT_S
+#include <sys/socket.h>
+#endif /* S_SPLINT_S */
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "gpsd_config.h"
+#include "gpsd.h"
+
+#define DGNSS_PROTO_DGPSIP	"dgpsip://"
+#define DGNSS_PROTO_NTRIP	"ntrip://"
+
+/* Where to find the list of DGPSIP correction servers, if there is one */
+#define DGPSIP_SERVER_LIST	"/usr/share/gpsd/dgpsip-servers"
+
+bool dgnss_url(char *name)
+/* is given string a valid URL for DGPS service? */
+{
+    return
+	strncmp(name,DGNSS_PROTO_NTRIP,strlen(DGNSS_PROTO_NTRIP))==0
+	|| strncmp(name,DGNSS_PROTO_DGPSIP,strlen(DGNSS_PROTO_DGPSIP))==0;
+}
+
+
+/*@ -branchstate */
+int dgnss_open(struct gps_context_t *context, char *dgnss_service)
+/* open a connection to a DGNSS service */
+{
+#ifdef NTRIP_ENABLE
+    if (strncmp(dgnss_service,DGNSS_PROTO_NTRIP,strlen(DGNSS_PROTO_NTRIP))==0)
+	return ntrip_open(context, dgnss_service + strlen(DGNSS_PROTO_NTRIP));
+#endif
+
+    if (strncmp(dgnss_service,DGNSS_PROTO_DGPSIP,strlen(DGNSS_PROTO_DGPSIP))==0)
+	return dgpsip_open(context, dgnss_service + strlen(DGNSS_PROTO_DGPSIP));
+
+#ifndef REQUIRE_DGNSS_PROTO
+    return dgpsip_open(context, dgnss_service);
+#else
+    gpsd_report(LOG_ERROR, "Unknown or unspecified DGNSS protocol for service %s\n",
+		dgnss_service);
+    return -1;
+#endif
+}
+/*@ +branchstate */
+
+int dgnss_poll(struct gps_context_t *context)
+/* poll the DGNSS service for a correction report */
+{
+    if (context->dsock > -1) {
+	context->rtcmbytes = read(context->dsock, context->rtcmbuf, sizeof(context->rtcmbuf));
+	if ((context->rtcmbytes == -1 && errno != EAGAIN) ||
+	    (context->rtcmbytes == 0)) {
+	    (void)shutdown(context->dsock, SHUT_RDWR);
+	    (void)close(context->dsock);
+	    return -1;
+	} else
+	    context->rtcmtime = timestamp();
+    }
+    return 0;
+}
+
+void dgnss_report(struct gps_device_t *session)
+/* may be time to ship a usage report to the DGNSS service */
+{
+    if (session->context->dgnss_service == dgnss_dgpsip)
+	dgpsip_report(session);
+#ifdef NTRIP_ENABLE
+    else if (session->context->dgnss_service == dgnss_ntrip)
+	ntrip_report(session);
+#endif
+}
+
+void dgnss_autoconnect(struct gps_context_t *context, double lat, double lon)
+{
+    if (context->dgnss_service != dgnss_ntrip) {
+	dgpsip_autoconnect(context, lat, lon, DGPSIP_SERVER_LIST);
+    }
+}
+
+void rtcm_relay(struct gps_device_t *session)
+/* pass a DGNSS connection report to a session */
+{
+    if (session->gpsdata.gps_fd !=-1
+	&& session->context->rtcmbytes > -1
+	&& session->rtcmtime < session->context->rtcmtime
+	&& session->device_type->rtcm_writer != NULL) {
+	if (session->device_type->rtcm_writer(session,
+					      session->context->rtcmbuf,
+					      (size_t)session->context->rtcmbytes) == 0)
+	    gpsd_report(LOG_ERROR, "Write to RTCM sink failed\n");
+	else {
+	    session->rtcmtime = timestamp();
+	    gpsd_report(LOG_IO, "<= DGPS: %zd bytes of RTCM relayed.\n", session->context->rtcmbytes);
+	}
+    }
+}
+