x11vnc: add avahi (aka mDNS/Zeroconf/Bonjour...) support thanks to Diego Petteno. add -find -create

1 files changed, 207 insertions, 0 deletions

diff --git a/x11vnc/avahi.c b/x11vnc/avahi.c
new file mode 100644
index 0000000..f4642c6
--- /dev/null
+++ b/x11vnc/avahi.c
@@ -0,0 +1,207 @@
+/* -- avahi.c -- */
+
+#include "x11vnc.h"
+
+void avahi_initialise(void);
+void avahi_advertise(const char *name, const char *host, const uint16_t port);
+void avahi_reset(void);
+void avahi_cleanup(void);
+
+#if !defined(LIBVNCSERVER_HAVE_AVAHI) || !defined(LIBVNCSERVER_HAVE_LIBPTHREAD)
+void avahi_initialise(void) {
+	rfbLog("avahi_initialise: no Avahi support at buildtime.\n");
+}
+void avahi_advertise(const char *name, const char *host, const uint16_t port) {
+	if (!name || !host || !port) {}
+	rfbLog("avahi_advertise:  no Avahi support at buildtime.\n");
+}
+void avahi_reset(void) {
+	rfbLog("avahi_reset: no Avahi support at buildtime.\n");
+}
+void avahi_cleanup(void) {
+	rfbLog("avahi_cleanup: no Avahi support at buildtime.\n");
+}
+#else
+
+#include <avahi-common/thread-watch.h>
+#include <avahi-common/alternative.h>
+#include <avahi-client/client.h>
+#include <avahi-client/publish.h>
+
+static AvahiThreadedPoll *_poll = NULL;
+static AvahiClient *_client = NULL;
+static AvahiEntryGroup *_group = NULL;
+
+static int db = 0;
+
+void avahi_initialise(void) {
+	int ret;
+
+	if (getenv("AVAHI_DEBUG")) {
+		db = 1;
+	}
+
+if (db) fprintf(stderr, "in  avahi_initialise\n");
+	if (_poll) {
+if (db) fprintf(stderr, "    avahi_initialise: poll not null\n");
+		return;
+	}
+
+	if (! (_poll = avahi_threaded_poll_new()) ) {
+		rfbLog("warning: unable to open Avahi poll.\n");
+		return;
+	}
+
+	_client = avahi_client_new(avahi_threaded_poll_get(_poll),
+	    0, NULL, NULL, &ret);
+	if (! _client) {
+		rfbLog("warning: unable to open Avahi client: %s\n",
+		    avahi_strerror(ret));
+
+		avahi_threaded_poll_free(_poll);
+		_poll = NULL;
+		return;
+	}
+
+	if (avahi_threaded_poll_start(_poll) < 0) {
+		rfbLog("warning: unable to start Avahi poll.\n");
+		avahi_client_free(_client);
+		_client = NULL;
+		avahi_threaded_poll_free(_poll);
+		_poll = NULL;
+		return;
+	}
+if (db) fprintf(stderr, "out avahi_initialise\n");
+}
+
+typedef struct {
+	const char *name;
+	const char *host;
+	uint16_t port;
+} avahi_service_t;
+
+static void _avahi_create_services(const char *name, const char *host,
+    const uint16_t port);
+
+static void _avahi_entry_group_callback(AvahiEntryGroup *g,
+    AvahiEntryGroupState state, void *userdata) {
+	char *new_name;
+	avahi_service_t *svc = (avahi_service_t *)userdata;
+
+if (db) fprintf(stderr, "in  _avahi_entry_group_callback %d 0x%p\n", state, svc);
+	if (g != _group && _group != NULL) {
+		rfbLog("avahi_entry_group_callback fatal error (group).\n");
+		clean_up_exit(1);
+	}
+	if (userdata == NULL) {
+		rfbLog("avahi_entry_group_callback fatal error (userdata).\n");
+		clean_up_exit(1);
+	}
+
+	switch(state) {
+	case AVAHI_ENTRY_GROUP_ESTABLISHED:
+		rfbLog("Avahi group %s established.\n", svc->name);
+#if 0		/* is this the segv problem? */
+		free(svc);
+#endif
+		break;
+	case AVAHI_ENTRY_GROUP_COLLISION:
+		new_name = avahi_alternative_service_name(svc->name);
+		_avahi_create_services(new_name, svc->host, svc->port);
+		rfbLog("Avahi Entry group collision\n");
+		avahi_free(new_name);
+		break;
+	case AVAHI_ENTRY_GROUP_FAILURE:
+		rfbLog("Avahi Entry group failure: %s\n",
+		    avahi_strerror(avahi_client_errno(
+		    avahi_entry_group_get_client(g))));
+		break;
+	}
+if (db) fprintf(stderr, "out _avahi_entry_group_callback\n");
+}
+
+static void _avahi_create_services(const char *name, const char *host,
+    const uint16_t port) {
+	avahi_service_t *svc = (avahi_service_t *)malloc(sizeof(avahi_service_t));
+	int ret = 0;
+
+if (db) fprintf(stderr, "in  _avahi_create_services  %s %s %d\n", name, host, port);
+	svc->name = name;
+	svc->host = host;
+	svc->port = port;
+
+	if (!_group) {
+if (db) fprintf(stderr, "    _avahi_create_services create group\n");
+		_group = avahi_entry_group_new(_client,
+		    _avahi_entry_group_callback, svc);
+	}
+	if (!_group) {
+		rfbLog("avahi_entry_group_new() failed: %s\n",
+		    avahi_strerror(avahi_client_errno(_client)));
+		return;
+	}
+
+	ret = avahi_entry_group_add_service(_group, AVAHI_IF_UNSPEC,
+	    AVAHI_PROTO_UNSPEC, 0, name, "_rfb._tcp", NULL, NULL, port, NULL);
+	if (ret < 0) {
+		rfbLog("Failed to add _rfb._tcp service: %s\n",
+		    avahi_strerror(ret));
+		return;
+	}
+
+	ret = avahi_entry_group_commit(_group);
+	if (ret < 0) {
+		rfbLog("Failed to commit entry_group:: %s\n",
+		    avahi_strerror(ret));
+		return;
+	}
+if (db) fprintf(stderr, "out _avahi_create_services\n");
+}
+
+void avahi_advertise(const char *name, const char *host, const uint16_t port) {
+if (db) fprintf(stderr, "in  avahi_advertise\n");
+	if (!_client) {
+if (db) fprintf(stderr, "    avahi_advertise client null\n");
+		return;
+	}
+	if (_poll == NULL) {
+		rfbLog("Avahi poll not initialized.\n");
+		return;
+	}
+
+	avahi_threaded_poll_lock(_poll);
+	_avahi_create_services(name, host, port >= 5900 ? port : 5900+port);
+	avahi_threaded_poll_unlock(_poll);
+if (db) fprintf(stderr, "out avahi_advertise\n");
+}
+
+void avahi_reset(void) {
+if (db) fprintf(stderr, "in  avahi_reset\n");
+	if (!_client || !_group) {
+if (db) fprintf(stderr, "    avahi_reset client/group null\n");
+		return;
+	}
+	avahi_entry_group_reset(_group);
+	rfbLog("Avahi resetting group.\n");
+if (db) fprintf(stderr, "out avahi_reset\n");
+}
+
+void avahi_cleanup(void) {
+if (db) fprintf(stderr, "in  avahi_cleanup\n");
+	if (!_client) {
+if (db) fprintf(stderr, "    avahi_cleanup client null\n");
+		return;
+	}
+	avahi_threaded_poll_lock(_poll);
+	avahi_threaded_poll_stop(_poll);
+
+	avahi_client_free(_client);
+	_client = NULL;
+
+	avahi_threaded_poll_free(_poll);
+	_poll = NULL;
+if (db) fprintf(stderr, "out avahi_cleanup\n");
+}
+
+#endif
+