1 files changed, 106 insertions, 2 deletions

diff --git a/x11vnc/avahi.c b/x11vnc/avahi.c
index 3d60388..830fabd 100644
--- a/x11vnc/avahi.c
+++ b/x11vnc/avahi.c
@@ -7,18 +7,122 @@ void avahi_advertise(const char *name, const char *host, const uint16_t port);
 void avahi_reset(void);
 void avahi_cleanup(void);
 
+static pid_t avahi_pid = 0;
+
+static void kill_avahi_pid(void) {
+	if (avahi_pid != 0) {
+		kill(avahi_pid, SIGTERM);
+		avahi_pid = 0;
+	}
+}
+
+static int try_avahi_helper(const char *name, const char *host, const uint16_t port) {
+#if LIBVNCSERVER_HAVE_FORK
+	char *cmd, *p, *path = getenv("PATH"), portstr[32];
+	int i;
+
+	/* avahi-publish */
+	if (no_external_cmds || !cmd_ok("zeroconf")) {
+		return 0;
+	}
+
+	if (!path) {
+		return 0;
+	}
+
+	path = strdup(path); 
+	cmd = (char *) malloc(strlen(path) + 100);
+	sprintf(portstr, "%d", (int) port);
+
+	p = strtok(path, ":");
+	while (p) {
+		struct stat sbuf;
+
+		sprintf(cmd, "%s/avahi-publish", p);
+		if (stat(cmd, &sbuf) == 0) {
+			break;
+		}
+		sprintf(cmd, "%s/dns-sd", p);
+		if (stat(cmd, &sbuf) == 0) {
+			break;
+		}
+		sprintf(cmd, "%s/mDNS", p);
+		if (stat(cmd, &sbuf) == 0) {
+			break;
+		}
+		cmd[0] = '\0';
+
+		p = strtok(NULL, ":");
+	}
+	free(path);
+
+	if (!strcmp(cmd, "")) {
+		free(cmd);
+		rfbLog("Could not find an external avahi/zeroconf helper program.\n");
+		return 0;
+	}
+
+	avahi_pid = fork();
+
+	if (avahi_pid < 0) {
+		rfbLogPerror("fork");
+		avahi_pid = 0;
+		free(cmd);
+		return 0;
+	}
+
+	if (avahi_pid != 0) {
+		int status;
+
+		usleep(500 * 1000);
+		waitpid(avahi_pid, &status, WNOHANG); 
+		if (kill(avahi_pid, 0) != 0) {
+			waitpid(avahi_pid, &status, WNOHANG); 
+			avahi_pid = 0;
+			free(cmd);
+			return 0;
+		}
+		if (! quiet) {
+			rfbLog("%s helper pid is: %d\n", cmd, (int) avahi_pid);
+		}
+		free(cmd);
+		return 1;
+	}
+
+	for (i=3; i<256; i++) {
+		close(i);
+	}
+
+	if (strstr(cmd, "/avahi-publish")) {
+		execlp(cmd, cmd, "-s", name, "_rfb._tcp", portstr, (char *) NULL);
+	} else {
+		execlp(cmd, cmd, "-R", name, "_rfb._tcp", ".", portstr, (char *) NULL);
+	}
+	exit(1);
+#else
+	if (!name || !host || !port) {}
+	return 0;
+#endif
+}
+
 #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");
+	if (!try_avahi_helper(name, host, port)) {
+		rfbLog("avahi_advertise:  no Avahi support at buildtime.\n");
+	}
 }
+
 void avahi_reset(void) {
+	kill_avahi_pid();
 	rfbLog("avahi_reset: no Avahi support at buildtime.\n");
 }
+
 void avahi_cleanup(void) {
+	kill_avahi_pid();
 	rfbLog("avahi_cleanup: no Avahi support at buildtime.\n");
 }
 #else