binding: nfc: Fix segmentation fault.

 Bug-AGL: SPEC-1959

 Duplicate reply (xreq_reply_cb) causes the segmentation fault when the
 adapter is plugged in at boot time. Several changes have been applied to
 fix this issue:

   - remove reply on subscribe for presence_event(only reply from loop);
   - power the adapter up only after configuration is complete;
   - update req & api artifacts to implement v3 bindings.

Change-Id: I945de9dc1fee0a95859f28b9d77b627cb998fa1b
Signed-off-by: Raquel Medina <raquel.medina@konsulko.com>

1 files changed, 84 insertions, 55 deletions

diff --git a/binding/afm-nfc-binding.c b/binding/afm-nfc-binding.c
index 94705de..40caa5a 100644
--- a/binding/afm-nfc-binding.c
+++ b/binding/afm-nfc-binding.c
@@ -41,8 +41,8 @@ static void neard_cb_record_found(const char *tag_name, void *ptr)
 {
 	nfc_binding_data *data = ptr;
 	neardal_record *record;
-	int ret = neardal_get_record_properties(tag_name, &record);
 
+	int ret = neardal_get_record_properties(tag_name, &record);
 	if (ret == NEARDAL_SUCCESS) {
 		GVariantIter iter;
 		char *s = NULL;
@@ -51,7 +51,8 @@ static void neard_cb_record_found(const char *tag_name, void *ptr)
 		json_object *jdict = json_object_new_object();
 
 		g_variant_iter_init(&iter, value);
-		json_object_object_add(jresp, "status", json_object_new_string("detected"));
+		json_object_object_add(jresp, "status",
+				json_object_new_string("detected"));
 
 		while (g_variant_iter_loop(&iter, "{sv}", &s, &v)) {
 			gchar *str;
@@ -59,11 +60,10 @@ static void neard_cb_record_found(const char *tag_name, void *ptr)
 			if (g_strcmp0("Name", s) == 0)
 				continue;
 
-			str = g_variant_print(v, 0);
+			str =  g_variant_print(v, 0);
 			str[strlen(str) - 1] = '\0';
-
-			json_object_object_add(jdict, s, json_object_new_string(str + 1));
-
+			json_object_object_add(jdict, s,
+					json_object_new_string(str + 1));
 			g_free(str);
 		}
 
@@ -77,7 +77,7 @@ static void neard_cb_record_found(const char *tag_name, void *ptr)
 		pthread_mutex_unlock(&mutex);
 
 		afb_event_push(presence_event, jresp);
-	}
+        }
 }
 
 static void neard_cb_tag_removed(const char *tag_name, void *ptr)
@@ -92,14 +92,15 @@ static void neard_cb_tag_removed(const char *tag_name, void *ptr)
 	}
 	pthread_mutex_unlock(&mutex);
 
-	json_object_object_add(jresp, "status", json_object_new_string("removed"));
+	json_object_object_add(jresp, "status",
+			       json_object_new_string("removed"));
 
 	afb_event_push(presence_event, jresp);
 
 	g_main_loop_quit(data->loop);
 }
 
-static void *neard_loop_thread(void *ptr)
+static void *poll_adapter(void *ptr)
 {
 	nfc_binding_data *data = ptr;
 	int ret;
@@ -109,10 +110,22 @@ static void *neard_loop_thread(void *ptr)
 	neardal_set_cb_tag_lost(neard_cb_tag_removed, ptr);
 	neardal_set_cb_record_found(neard_cb_record_found, ptr);
 
+	ret = neardal_set_adapter_property(data->adapter,
+					   NEARD_ADP_PROP_POWERED,
+					   GINT_TO_POINTER(1));
+	if (ret != NEARDAL_SUCCESS) {
+		AFB_API_DEBUG(afbBindingV3root,
+			"failed to power %s adapter on: ret=0x%x (%s)",
+			data->adapter, ret, neardal_error_get_text(ret));
+		g_free(data->adapter);
+		return NULL;
+	}
+
 	while (1) {
 		ret = neardal_start_poll(data->adapter);
 
-		if (ret != NEARDAL_SUCCESS)
+		if ((ret != NEARDAL_SUCCESS) &&
+		    (ret != NEARDAL_ERROR_POLLING_ALREADY_ACTIVE))
 			break;
 
 		g_main_loop_run(data->loop);
@@ -123,87 +136,103 @@ static void *neard_loop_thread(void *ptr)
 	return NULL;
 }
 
-static int init(afb_api_t api)
+static int get_adapter(nfc_binding_data *data, unsigned int id)
 {
-	pthread_t thread_id;
-	nfc_binding_data *data = NULL;
 	char **adapters = NULL;
 	int num_adapters, ret;
 
-	presence_event = afb_daemon_make_event("presence");
-
 	ret = neardal_get_adapters(&adapters, &num_adapters);
+	if (ret != NEARDAL_SUCCESS) {
+		AFB_API_DEBUG(afbBindingV3root,
+			      "failed to find adapters ret=0x%x (%s)",
+			      ret, neardal_error_get_text(ret));
 
-	if (ret == NEARDAL_SUCCESS) {
-		ret = neardal_set_adapter_property(adapters[0], NEARD_ADP_PROP_POWERED, GINT_TO_POINTER(1));
+		return -EIO;
+	}
 
-		if (ret == NEARDAL_SUCCESS) {
-			data = malloc(sizeof(nfc_binding_data));
+	if (id > num_adapters - 1) {
+		AFB_API_DEBUG(afbBindingV3root,
+			      "adapter out of range (%d - %d)",
+			      id, num_adapters);
+		return -EINVAL;
+	}
 
-			if (data == NULL)
-				return -ENOMEM;
+	data->adapter = g_strdup(adapters[id]);
+	neardal_free_array(&adapters);
 
-			afb_api_set_userdata(api, data);
+	return ret;
+}
 
-			data->adapter = g_strdup(adapters[0]);
-			ret = pthread_create(&thread_id, NULL, neard_loop_thread, data);
-		}
+static int init(afb_api_t api)
+{
+	nfc_binding_data *data;
+	pthread_t thread_id;
+	int ret;
+
+	data = g_malloc0(sizeof(nfc_binding_data));
+
+	presence_event = afb_api_make_event(api, "presence");
+	if (!afb_event_is_valid(presence_event)) {
+		AFB_API_ERROR(api, "Failed to create event");
+		return -EINVAL;
 	}
 
-	neardal_free_array(&adapters);
+	/* get the first adapter */
+	ret = get_adapter(data, 0);
+	if (ret != NEARDAL_SUCCESS)
+		return 0;
+
+	AFB_API_DEBUG(api, " %s adapter found", data->adapter);
+
+	afb_api_set_userdata(api, data);
+	ret = pthread_create(&thread_id, NULL, poll_adapter, data);
+	if (ret)
+		AFB_API_ERROR(api, "polling pthread creation failed");
 
 	return 0;
 }
 
 static void subscribe(afb_req_t request)
 {
-	const char *value = afb_req_value(request, "value");
-	afb_api_t api = afb_req_get_api(request);
-	nfc_binding_data *data = afb_api_get_userdata(api);
-
-	if (value && !strcasecmp(value, "presence")) {
-		afb_req_subscribe(request, presence_event);
-		afb_req_success(request, NULL, NULL);
-
-		// send initial tag if exists
-		pthread_mutex_lock(&mutex);
-		if (data && data->jresp) {
-			json_object_get(data->jresp);
-			afb_event_push(presence_event, data->jresp);
-		}
-		pthread_mutex_unlock(&mutex);
+	if (afb_req_subscribe(request, presence_event) < 0) {
+		AFB_REQ_ERROR(request, "subscribe to presence_event failed");
+		afb_req_reply(request, NULL, "failed", "Invalid event");
 
 		return;
 	}
 
-	afb_req_fail(request, "failed", "Invalid event");
+	afb_req_reply(request, NULL, NULL, NULL);
 }
 
 static void unsubscribe(afb_req_t request)
 {
-	const char *value = afb_req_value(request, "value");
+	if (afb_req_unsubscribe(request, presence_event) < 0) {
+		AFB_REQ_ERROR(request,
+			      "unsubscribe to presence_event failed");
+		afb_req_reply(request, NULL, "failed", "Invalid event");
 
-	if (value && !strcasecmp(value, "presence")) {
-		afb_req_unsubscribe(request, presence_event);
-		afb_req_success(request, NULL, NULL);
 		return;
 	}
 
-	afb_req_fail(request, "failed", "Invalid event");
+	afb_req_reply(request, NULL, NULL, NULL);
 }
 
-static const struct afb_verb_v3 binding_verbs[] = {
-	{ .verb = "subscribe",   .callback = subscribe,    .info = "Subscribe to NFC events" },
-	{ .verb = "unsubscribe", .callback = unsubscribe,  .info = "Unsubscribe to NFC events" },
+const afb_verb_t binding_verbs[] = {
+	{ .verb = "subscribe",   .callback = subscribe,
+	  .info = "Subscribe to NFC events" },
+	{ .verb = "unsubscribe", .callback = unsubscribe,
+	  .info = "Unsubscribe to NFC events" },
 	{ }
 };
 
 /*
  * binder API description
  */
-const struct afb_binding_v3 afbBindingV3 = {
-	.api		= "nfc",
-	.specification	= "NFC service API",
-	.verbs		= binding_verbs,
-	.init		= init,
+const afb_binding_t afbBindingExport = {
+	.api            = "nfc",
+	.specification  = "NFC service API",
+	.info           = "AGL nfc service",
+	.verbs          = binding_verbs,
+	.init           = init
 };
+