--- /dev/null
+
+#include "meshlink_internal.h"
+#include "discovery.h"
+
+#include <pthread.h>
+
+#include <avahi-core/core.h>
+#include <avahi-core/lookup.h>
+#include <avahi-core/publish.h>
+#include <avahi-common/simple-watch.h>
+#include <avahi-common/malloc.h>
+#include <avahi-common/alternative.h>
+#include <avahi-common/error.h>
+
+#define MESHLINK_MDNS_SERVICE_TYPE "_meshlink._tcp"
+#define MESHLINK_MDNS_SERVICE_NAME "Meshlink"
+
+
+static void discovery_entry_group_callback(AvahiServer *server, AvahiSEntryGroup *group, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata)
+{
+ meshlink_handle_t *mesh = userdata;
+
+ /* Called whenever the entry group state changes */
+ switch (state)
+ {
+ case AVAHI_ENTRY_GROUP_ESTABLISHED:
+ /* The entry group has been established successfully */
+ fprintf(stderr, "Service '%s' successfully established.\n", MESHLINK_MDNS_SERVICE_NAME);
+ break;
+
+ case AVAHI_ENTRY_GROUP_COLLISION:
+ fprintf(stderr, "Service name collision '%s'\n", MESHLINK_MDNS_SERVICE_NAME);
+ break;
+
+ case AVAHI_ENTRY_GROUP_FAILURE :
+ fprintf(stderr, "Entry group failure: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server)));
+
+ /* Some kind of failure happened while we were registering our services */
+ avahi_simple_poll_quit(mesh->avahi_poll);
+ break;
+
+ case AVAHI_ENTRY_GROUP_UNCOMMITED:
+ case AVAHI_ENTRY_GROUP_REGISTERING:
+ ;
+ }
+}
+
+
+static void discovery_create_services(meshlink_handle_t *mesh)
+{
+ /* If this is the first time we're called, let's create a new entry group */
+ if (!mesh->avahi_group)
+ if (!(mesh->avahi_group = avahi_s_entry_group_new(mesh->avahi_server, discovery_entry_group_callback, NULL))) {
+ fprintf(stderr, "avahi_entry_group_new() failed: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server)));
+ goto fail;
+ }
+
+ fprintf(stderr, "Adding service '%s'\n", MESHLINK_MDNS_SERVICE_NAME);
+
+ /* Create some random TXT data */
+ char fingerprint[1024];
+ snprintf(fingerprint, sizeof(fingerprint), "fingerprint=%s", /*meshlink_get_fingerprint(mesh, mesh->self)*/ "");
+
+ /* Add the service for IPP */
+ int ret = 0;
+ if ((ret = avahi_server_add_service(mesh->avahi_server, mesh->avahi_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, MESHLINK_MDNS_SERVICE_NAME, MESHLINK_MDNS_SERVICE_TYPE, NULL, NULL, mesh->myport ? atoi(mesh->myport) : 655, fingerprint, NULL)) < 0) {
+ fprintf(stderr, "Failed to add _ipp._tcp service: %s\n", avahi_strerror(ret));
+ goto fail;
+ }
+
+ /* Tell the server to register the service */
+ if ((ret = avahi_s_entry_group_commit(mesh->avahi_group)) < 0) {
+ fprintf(stderr, "Failed to commit entry_group: %s\n", avahi_strerror(ret));
+ goto fail;
+ }
+
+ return;
+
+fail:
+ avahi_simple_poll_quit(mesh->avahi_poll);
+}
+
+static void discovery_server_callback(AvahiServer *server, AvahiServerState state, AVAHI_GCC_UNUSED void * userdata)
+{
+ meshlink_handle_t *mesh = userdata;
+
+ switch (state)
+ {
+ case AVAHI_SERVER_RUNNING:
+ /* The serve has startup successfully and registered its host
+ * name on the network, so it's time to create our services */
+ if (!mesh->avahi_group)
+ discovery_create_services(mesh);
+ break;
+
+ case AVAHI_SERVER_COLLISION:
+ /* A host name collision happened. Let's do nothing */
+ break;
+
+ case AVAHI_SERVER_REGISTERING:
+ /* Let's drop our registered services. When the server is back
+ * in AVAHI_SERVER_RUNNING state we will register them
+ * again with the new host name. */
+ //if (mesh->avahi_group)
+ // avahi_s_entry_group_reset(mesh->avahi_group);
+ break;
+
+ case AVAHI_SERVER_FAILURE:
+ /* Terminate on failure */
+ fprintf(stderr, "Server failure: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server)));
+ avahi_simple_poll_quit(mesh->avahi_poll);
+ break;
+
+ case AVAHI_SERVER_INVALID:
+ break;
+ }
+}
+
+static void discovery_browse_callback(
+ AvahiSServiceBrowser *browser,
+ AvahiIfIndex interface,
+ AvahiProtocol protocol,
+ AvahiBrowserEvent event,
+ const char *name,
+ const char *type,
+ const char *domain,
+ AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
+ void* userdata)
+{
+ meshlink_handle_t *mesh = userdata;
+
+ /* Called whenever a new services becomes available on the LAN or is removed from the LAN */
+
+ switch (event)
+ {
+ case AVAHI_BROWSER_FAILURE:
+ fprintf(stderr, "(Browser) %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server)));
+ avahi_simple_poll_quit(mesh->avahi_poll);
+ return;
+
+ case AVAHI_BROWSER_NEW:
+ fprintf(stderr, "(Browser) NEW: service '%s' of type '%s' in domain '%s'\n", name, type, domain);
+ /* We ignore the returned resolver object. In the callback
+ function we free it. If the server is terminated before
+ the callback function is called the server will free
+ the resolver for us. */
+ //if (!(avahi_s_service_resolver_new(s, interface, protocol, name, type, domain, AVAHI_PROTO_UNSPEC, 0, resolve_callback, server)))
+ // fprintf(stderr, "Failed to resolve service '%s': %s\n", name, avahi_strerror(avahi_server_errno(server)));
+ break;
+
+ case AVAHI_BROWSER_REMOVE:
+ fprintf(stderr, "(Browser) REMOVE: service '%s' of type '%s' in domain '%s'\n", name, type, domain);
+ break;
+
+ case AVAHI_BROWSER_ALL_FOR_NOW:
+ case AVAHI_BROWSER_CACHE_EXHAUSTED:
+ fprintf(stderr, "(Browser) %s\n", event == AVAHI_BROWSER_CACHE_EXHAUSTED ? "CACHE_EXHAUSTED" : "ALL_FOR_NOW");
+ break;
+ }
+}
+
+static void *discovery_loop(void *arg)
+{
+ meshlink_handle_t *mesh = arg;
+
+ avahi_simple_poll_loop(mesh->avahi_poll);
+
+ return NULL;
+}
+
+bool discovery_start(meshlink_handle_t *mesh)
+{
+ // Allocate discovery loop object
+ if (!(mesh->avahi_poll = avahi_simple_poll_new())) {
+ fprintf(stderr, "Failed to create discovery poll object.\n");
+ goto fail;
+ }
+
+ // Let's set the host name for this server.
+ AvahiServerConfig config;
+ avahi_server_config_init(&config);
+ config.host_name = avahi_strdup(mesh->name);
+ config.publish_workstation = 0;
+
+ /* Allocate a new server */
+ int error;
+ mesh->avahi_server = avahi_server_new(avahi_simple_poll_get(mesh->avahi_poll), &config, discovery_server_callback, NULL, &error);
+
+ /* Free the configuration data */
+ avahi_server_config_free(&config);
+
+ /* Check wether creating the server object succeeded */
+ if (!mesh->avahi_server) {
+ fprintf(stderr, "Failed to create discovery server: %s\n", avahi_strerror(error));
+ goto fail;
+ }
+
+ // Create the service browser
+ if (!(mesh->avahi_browser = avahi_s_service_browser_new(mesh->avahi_server, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, MESHLINK_MDNS_SERVICE_TYPE, NULL, 0, discovery_browse_callback, mesh))) {
+ fprintf(stderr, "Failed to create discovery service browser: %s\n", avahi_strerror(avahi_server_errno(mesh->avahi_server)));
+ goto fail;
+ }
+
+ // Start the discovery thread
+ if(pthread_create(&mesh->discovery_thread, NULL, discovery_loop, mesh) != 0) {
+ fprintf(stderr, "Could not start discovery thread: %s\n", strerror(errno));
+ memset(&mesh->discovery_thread, 0, sizeof mesh->discovery_thread);
+ goto fail;
+ }
+
+ mesh->discovery_threadstarted = true;
+
+ return true;
+
+fail:
+ if (mesh->avahi_browser)
+ avahi_s_service_browser_free(mesh->avahi_browser);
+
+ if (mesh->avahi_server)
+ avahi_server_free(mesh->avahi_server);
+
+ if (mesh->avahi_poll)
+ avahi_simple_poll_free(mesh->avahi_poll);
+
+ return false;
+}
+
+void discovery_stop(meshlink_handle_t *mesh)
+{
+ // @TODO: Shut down
+ avahi_simple_poll_quit(mesh->avahi_poll);
+
+ // Wait for the discovery thread to finish
+
+ pthread_join(mesh->discovery_thread, NULL);
+
+ // Clean up resources
+ if (mesh->avahi_browser)
+ avahi_s_service_browser_free(mesh->avahi_browser);
+
+ if (mesh->avahi_server)
+ avahi_server_free(mesh->avahi_server);
+
+ if (mesh->avahi_poll)
+ avahi_simple_poll_free(mesh->avahi_poll);
+}
projects / meshlink / commitdiff