avahi service publishing

CMakeLists.txt

@@ -84,6 +84,7 @@ else()
 	list(APPEND SUNSHINE_DEFINITIONS APPS_JSON="apps_linux.json")
 
 	find_package(X11 REQUIRED)
+	pkg_check_modules(AVAHI REQUIRED avahi-client)
 	set(PLATFORM_TARGET_FILES
 		sunshine/platform/linux/display.cpp
 		sunshine/platform/linux/input.cpp)
@@ -98,10 +99,12 @@ else()
 		evdev
 		pulse
 		pulse-simple
+		${AVAHI_LIBRARIES}
 		)
 	
 	set(PLATFORM_INCLUDE_DIRS
 		${X11_INCLUDE_DIR}
+		${AVAHI_INCLUDE_DIRS}
 		/usr/include/libevdev-1.0)
 
 	if(NOT DEFINED SUNSHINE_EXECUTABLE_PATH)
@@ -152,6 +155,8 @@ set(SUNSHINE_TARGET_FILES
 	sunshine/thread_safe.h
 	sunshine/sync.h
 	sunshine/round_robin.h
+	sunshine/publish.h
+	sunshine/publish.cpp
 	${PLATFORM_TARGET_FILES})
 
 include_directories(

README.md

@@ -13,7 +13,7 @@ Sunshine is a Gamestream host for Moonlight
 ### Requirements:
 Ubuntu 20.04:
 
-	sudo apt install cmake libssl-dev libavdevice-dev libboost-thread-dev libboost-filesystem-dev libboost-log-dev libpulse-dev libopus-dev libxtst-dev libx11-dev libxfixes-dev libevdev-dev libxcb1-dev libxcb-shm0-dev libxcb-xfixes0-dev
+	sudo apt install cmake libssl-dev libavdevice-dev libboost-thread-dev libboost-filesystem-dev libboost-log-dev libpulse-dev libopus-dev libxtst-dev libx11-dev libxfixes-dev libevdev-dev libxcb1-dev libxcb-shm0-dev libxcb-xfixes0-dev libavahi-client-dev
 
 ### Compilation:
 - `git clone https://github.com/loki-47-6F-64/sunshine.git --recurse-submodules`

sunshine/main.cpp

@@ -20,6 +20,7 @@
 #include "rtsp.h"
 #include "config.h"
 #include "thread_pool.h"
+#include "publish.h"
 
 #include "platform/common.h"
 extern "C" {
@@ -147,6 +148,7 @@ int main(int argc, char *argv[]) {
   task_pool.start(1);
 
   std::thread httpThread { nvhttp::start, shutdown_event };
+  std::thread publishThread { publish::start, shutdown_event };
   stream::rtpThread(shutdown_event);
 
   httpThread.join();

sunshine/nvhttp.cpp

@@ -29,8 +29,6 @@
 
 namespace nvhttp {
 using namespace std::literals;
-constexpr auto PORT_HTTP  = 47989;
-constexpr auto PORT_HTTPS = 47984;
 
 constexpr auto VERSION     = "7.1.400.0";
 constexpr auto GFE_VERSION = "3.12.0.1";

sunshine/nvhttp.h

@@ -15,6 +15,8 @@
 #define CERTIFICATE_FILE CA_DIR    "/cacert.pem"
 
 namespace nvhttp {
+constexpr auto PORT_HTTP  = 47989;
+constexpr auto PORT_HTTPS = 47984;
 void start(std::shared_ptr<safe::signal_t> shutdown_event);
 }
 

sunshine/publish.cpp

@@ -0,0 +1,134 @@
+
+// adapted from https://www.avahi.org/doxygen/html/client-publish-service_8c-example.html
+#include <thread>
+
+#include <avahi-client/client.h>
+#include <avahi-client/publish.h>
+#include <avahi-common/alternative.h>
+#include <avahi-common/error.h>
+#include <avahi-common/malloc.h>
+#include <avahi-common/simple-watch.h>
+#include <avahi-common/timeval.h>
+
+#include "publish.h"
+#include "nvhttp.h"
+#include "main.h"
+
+namespace publish {
+AvahiEntryGroup *group = NULL;
+AvahiSimplePoll *simple_poll = NULL;
+char *name = NULL;
+void create_services(AvahiClient *c);
+
+void entry_group_callback(AvahiEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) {
+  assert(g == group || group == NULL);
+  group = g;
+  switch (state) {
+  case AVAHI_ENTRY_GROUP_ESTABLISHED:
+    BOOST_LOG(info) << "Avahi service " << name << " successfully established.";
+    break;
+  case AVAHI_ENTRY_GROUP_COLLISION:
+    char *n;
+    n = avahi_alternative_service_name(name);
+    avahi_free(name);
+    name = n;
+    BOOST_LOG(info) << "Avahi service name collision, renaming service to " << name;
+    create_services(avahi_entry_group_get_client(g));
+    break;
+  case AVAHI_ENTRY_GROUP_FAILURE:
+    BOOST_LOG(error) << "Avahi entry group failure: " << avahi_strerror(avahi_client_errno(avahi_entry_group_get_client(g)));
+    avahi_simple_poll_quit(simple_poll);
+    break;
+  case AVAHI_ENTRY_GROUP_UNCOMMITED:
+  case AVAHI_ENTRY_GROUP_REGISTERING:
+    ;
+  }
+}
+
+void create_services(AvahiClient *c) {
+  char *n;
+  int ret;
+  assert(c);
+  if (!group) {
+    if (!(group = avahi_entry_group_new(c, entry_group_callback, NULL))) {
+      BOOST_LOG(error) << "avahi_entry_group_new() failed: " << avahi_strerror(avahi_client_errno(c));
+      goto fail;
+    }
+  }
+  if (avahi_entry_group_is_empty(group)) {
+    BOOST_LOG(info) << "Adding avahi service " << name;
+
+    if ((ret = avahi_entry_group_add_service(group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AvahiPublishFlags(0), name, SERVICE_TYPE, NULL, NULL, nvhttp::PORT_HTTP, NULL)) < 0) {
+      if (ret == AVAHI_ERR_COLLISION)
+        goto collision;
+      BOOST_LOG(error) << "Failed to add " << SERVICE_TYPE << " service: " << avahi_strerror(ret);
+      goto fail;
+    }
+    if ((ret = avahi_entry_group_commit(group)) < 0) {
+      BOOST_LOG(error) << "Failed to commit entry group: " << avahi_strerror(ret);
+      goto fail;
+    }
+  }
+  return;
+collision:
+  // A service name collision with a local service happened. Let's pick a new name
+  n = avahi_alternative_service_name(name);
+  avahi_free(name);
+  name = n;
+  BOOST_LOG(info) <<  "Service name collision, renaming service to " << name;
+  avahi_entry_group_reset(group);
+  create_services(c);
+  return;
+fail:
+  avahi_simple_poll_quit(simple_poll);
+}
+
+void client_callback(AvahiClient *c, AvahiClientState state, AVAHI_GCC_UNUSED void *userdata) {
+  assert(c);
+  switch (state) {
+  case AVAHI_CLIENT_S_RUNNING:
+    create_services(c);
+    break;
+  case AVAHI_CLIENT_FAILURE:
+    BOOST_LOG(error) << "Client failure: " << avahi_strerror(avahi_client_errno(c));
+    avahi_simple_poll_quit(simple_poll);
+    break;
+  case AVAHI_CLIENT_S_COLLISION:
+  case AVAHI_CLIENT_S_REGISTERING:
+    if (group)
+      avahi_entry_group_reset(group);
+    break;
+  case AVAHI_CLIENT_CONNECTING:
+    ;
+  }
+}
+
+void start(std::shared_ptr<safe::signal_t> shutdown_event) {
+  AvahiClient *client = NULL;
+  int error;
+  if (!(simple_poll = avahi_simple_poll_new())) {
+    fprintf(stderr, "Failed to create simple poll object.\n");
+    return;
+  }
+  name = avahi_strdup(SERVICE_NAME);
+  client = avahi_client_new(avahi_simple_poll_get(simple_poll), AvahiClientFlags(0), client_callback, NULL, &error);
+  if (!client) {
+    fprintf(stderr, "Failed to create client: %s\n", avahi_strerror(error));
+    avahi_simple_poll_free(simple_poll);
+    return;
+  }
+
+  std::thread poll_thread { avahi_simple_poll_loop, simple_poll };
+
+  // Wait for any event
+  shutdown_event->view();
+
+  avahi_simple_poll_quit(simple_poll);
+
+  poll_thread.join();
+  
+  avahi_client_free(client);
+  avahi_simple_poll_free(simple_poll);
+  avahi_free(name);
+}
+}; // namespace publish

sunshine/publish.h

@@ -0,0 +1,16 @@
+#ifndef SUNSHINE_PUBLISH_H
+#define SUNSHINE_PUBLISH_H
+
+#include <functional>
+#include <string>
+
+#include "thread_safe.h"
+
+#define SERVICE_NAME "Sunshine"
+#define SERVICE_TYPE "_nvstream._tcp"
+
+namespace publish {
+void start(std::shared_ptr<safe::signal_t> shutdown_event);
+}
+
+#endif //SUNSHINE_PUBLISH_H