Added a tutorial and fix few errorssandbox/ctxnop/binding-object

Added the tuto-5 that show how to benefit from the new 'binding-object'
header. Fix few errors that can cause segfault when dealing with events
and use the right afb::req object for verbs.

Change-Id: I0563dd72a2843b2b54c2e40398ba129aac05ff0c
Signed-off-by: Loïc Collignon <loic.collignon@iot.bzh>

4 files changed, 118 insertions, 25 deletions

diff --git a/bindings/tutorial/CMakeLists.txt b/bindings/tutorial/CMakeLists.txt
index 07b7e3f1..f05fa541 100644
--- a/bindings/tutorial/CMakeLists.txt
+++ b/bindings/tutorial/CMakeLists.txt
@@ -33,5 +33,6 @@ tuto(1 c)
 tuto(2 c)
 tuto(3 cpp)
 tuto(4 c)
+tuto(5 cpp)
 
 tuto(app1 c)
diff --git a/bindings/tutorial/tuto-5.cpp b/bindings/tutorial/tuto-5.cpp
new file mode 100644
index 00000000..458ae7b5
--- /dev/null
+++ b/bindings/tutorial/tuto-5.cpp
@@ -0,0 +1,93 @@
+#include <afb/c++/binding>
+#include <json-c/json.h>
+#include <string.h>
+
+class tuto5
+	: public afb::base_api_t<tuto5>
+{
+private:
+	afb::event event_login;
+	afb::event event_logout;
+
+public:
+	void login(afb::req req)
+	{
+		json_object *user, *passwd;
+
+		json_object* args = req.json();
+		if (!json_object_object_get_ex(args, "user", &user)
+		|| !json_object_object_get_ex(args, "password", &passwd)) {
+			AFB_REQ_ERROR(req, "login, bad request: %s", json_object_get_string(args));
+			req.fail("bad-request");
+		} else if (afb_req_context_get(req)) {
+			AFB_REQ_ERROR(req, "login, bad state, logout first");
+			req.fail("bad-state");
+		} else if (std::string(json_object_get_string(passwd)) != std::string("please")) {
+			AFB_REQ_ERROR(req, "login, unauthorized: %s", json_object_get_string(args));
+			req.fail("unauthorized");
+		} else {
+			char* username = strdup(json_object_get_string(user));
+			AFB_REQ_NOTICE(req, "login user: %s", username);
+			req.session_set_LOA(1);
+			afb_req_context_set(req, username, free);
+			req.success();
+			event_login.push(json_object_new_string(username));
+		}
+	}
+
+	void action(afb::req req) const
+	{
+		json_object* val;
+		json_object* args = req.json();
+		char* username = reinterpret_cast<char*>(afb_req_context_get(req));
+		AFB_REQ_NOTICE(req, "action for user %s: %s", username, json_object_get_string(args));
+		if (json_object_object_get_ex(args, "subscribe", &val)) {
+			if (json_object_get_boolean(val)) {
+				AFB_REQ_NOTICE(req, "user %s subscribes to events", username);
+				req.subscribe(event_login);
+				req.subscribe(event_logout);
+			} else {
+				AFB_REQ_NOTICE(req, "user %s unsubscribes to events", username);
+				req.unsubscribe(event_login);
+				req.unsubscribe(event_logout);
+			}
+		}
+		req.success(json_object_get(args));
+	}
+
+	void logout(afb::req req)
+	{
+		char* username = reinterpret_cast<char*>(afb_req_context_get(req));
+		AFB_REQ_NOTICE(req, "login user %s out", username);
+		event_logout.push(json_object_new_string(username));
+		req.session_set_LOA(0);
+		afb_req_context_clear(req);
+		req.success();
+	}
+
+	int preinit(afb_api_t h) override
+	{
+		return !(
+			(add_verb<&tuto5::login>("login", "log in the system") == 0) &&
+			(add_verb<&tuto5::action>("action", "perform an action", nullptr, nullptr, AFB_SESSION_LOA_1) == 0) &&
+			(add_verb<&tuto5::logout>("logout", "log out the system", nullptr, nullptr, AFB_SESSION_LOA_1) == 0)
+		);
+	}
+
+	int init() override
+	{
+		AFB_API_NOTICE(api_, "init");
+		event_login = make_event("login");
+		event_logout = make_event("logout");
+		if (event_login.is_valid() && event_logout.is_valid())
+			return 0;
+		AFB_API_ERROR(api_, "Can't create events");
+		return -1;
+	}
+};
+
+int afbBindingEntry(afb_api_t h)
+{
+	afb::new_api<tuto5>(h, "tuto-5", "fifth tutorial: C++");
+	return 0;
+}
diff --git a/include/afb/c++/binding-object.hpp b/include/afb/c++/binding-object.hpp
index 307189b9..1744535f 100644
--- a/include/afb/c++/binding-object.hpp
+++ b/include/afb/c++/binding-object.hpp
@@ -57,12 +57,12 @@ namespace afb
 		/**
 		 * @brief TApi's method pointer.
 		 */
-		using TVerbCallback = void(TApi::*)(afb_req_t);
+		using TVerbCallback = void(TApi::*)(req);
 
 		/***
 		 * @brief TApi's const method pointer.
 		 */
-		using TVerbCallbackConst = void(TApi::*)(afb_req_t) const;
+		using TVerbCallbackConst = void(TApi::*)(req) const;
 
 		/**
 		 * @brief Pre-init callback for an api created using @c afb::api::new_api.
@@ -91,7 +91,7 @@ namespace afb
 				return -2;
 			}
 
-			api->handle_ = handle;
+			api->api_ = handle;
 			return api->preinit(handle);
 		}
 
@@ -131,30 +131,30 @@ namespace afb
 		/**
 		 * @brief Verb callback for a verb added using @c afb::api::add_verb.
 		 * @tparam callback TApi's method to call
-		 * @param[in] req Request to handle.
+		 * @param[in] r Request to handle.
 		 */
 		template <TVerbCallback callback>
-		static void verb(afb_req_t req)
+		static void verb(afb_req_t r)
 		{
-			assert(req != nullptr);
+			assert(r != nullptr);
 
-			afb_api_t handle = afb_req_get_api(req);
+			afb_api_t handle = afb_req_get_api(r);
 			if (handle)
 			{
 				void* userdata = afb_api_get_userdata(handle);
 				if (userdata)
 				{
 					TApi* api = reinterpret_cast<TApi*>(userdata);
-					(api->*callback)(req);
+					(api->*callback)(afb::req(r));
 				}
 				else
 				{
-					afb_req_fail(req, "Failed to get the API object!", nullptr);
+					afb_req_fail(r, "Failed to get the API object!", nullptr);
 				}
 			}
 			else
 			{
-				afb_req_fail(req, "Failed to get the corresponding API from the query!", nullptr);
+				afb_req_fail(r, "Failed to get the corresponding API from the query!", nullptr);
 			}
 		}
 
@@ -164,27 +164,27 @@ namespace afb
 		 * @param[in] req Request to handle.
 		 */
 		template <TVerbCallbackConst callback>
-		static void verb(afb_req_t req)
+		static void verb(afb_req_t r)
 		{
-			assert(req != nullptr);
+			assert(r != nullptr);
 
-			afb_api_t handle = afb_req_get_api(req);
+			afb_api_t handle = afb_req_get_api(r);
 			if (handle)
 			{
 				void* userdata = afb_api_get_userdata(handle);
 				if (userdata)
 				{
 					TApi* api = reinterpret_cast<TApi*>(userdata);
-					(api->*callback)(req);
+					(api->*callback)(afb::req(r));
 				}
 				else
 				{
-					afb_req_fail(req, "Failed to get the API object!", nullptr);
+					afb_req_fail(r, "Failed to get the API object!", nullptr);
 				}
 			}
 			else
 			{
-				afb_req_fail(req, "Failed to get the corresponding API from the query!", nullptr);
+				afb_req_fail(r, "Failed to get the corresponding API from the query!", nullptr);
 			}
 		}
 	};
@@ -212,8 +212,6 @@ namespace afb
 		base_api_t& operator=(const base_api_t&) = delete;
 
 	protected:
-		afb_api_t handle_;
-
 		/**
 		 * @brief Default constructor.
 		 */
@@ -238,7 +236,7 @@ namespace afb
 		int add_verb(const std::string& verb, const std::string& info, void* vcbdata = nullptr, const struct afb_auth* auth = nullptr, uint32_t session = AFB_SESSION_NONE_X2, int glob = 0)
 		{
 			return afb_api_add_verb(
-				handle_,
+				api_,
 				verb.c_str(),
 				info == "" ? nullptr : info.c_str(),
 				TTraits::template verb<Callback>,
@@ -263,7 +261,7 @@ namespace afb
 		int add_verb(const std::string& verb, const std::string& info, void* vcbdata = nullptr, const struct afb_auth* auth = nullptr, uint32_t session = AFB_SESSION_NONE_X2, int glob = 0)
 		{
 			return afb_api_add_verb(
-				handle_,
+				api_,
 				verb.c_str(),
 				info == "" ? nullptr : info.c_str(),
 				TTraits::template verb<Callback>,
@@ -284,21 +282,21 @@ namespace afb
 		 * @brief Get the API's handle.
 		 * @return The API's handle.
 		 */
-		afb_api_t handle() const { return handle_; }
+		afb_api_t handle() const { return api_; }
 
 		/**
 		 * @brief Implicit conversion to C handle.
 		 * @return The API's handle.
 		 */
-		operator afb_api_t() const { return handle_; }
+		operator afb_api_t() const { return api_; }
 
 		/**
 		 * @brief Destructor.
 		 */
 		virtual ~base_api_t()
 		{
-			if (handle_ && afb_api_delete_api(handle_))
-				AFB_API_ERROR(handle_, "Failed to delete API.");
+			if (api_ && afb_api_delete_api(api_))
+				AFB_API_ERROR(api_, "Failed to delete API.");
 		}
 
 		/**
diff --git a/include/afb/c++/binding-wrap.hpp b/include/afb/c++/binding-wrap.hpp
index 04f4add1..ae0e5eeb 100644
--- a/include/afb/c++/binding-wrap.hpp
+++ b/include/afb/c++/binding-wrap.hpp
@@ -90,6 +90,7 @@ bool callsync(const char *api, const char *verb, struct json_object *args, struc
 /* apis */
 class api
 {
+protected:
 	afb_api_t api_;
 public:
 	using call_cb = void (*)(void *closure, struct json_object *object, const char *error, const char *info, afb_api_t api);
@@ -406,7 +407,7 @@ inline bool event::is_valid() const { return afb_event_is_valid(event_); }
 inline int event::broadcast(json_object *object) const { return afb_event_broadcast(event_, object); }
 inline int event::push(json_object *object) const { return afb_event_push(event_, object); }
 
-inline void event::unref() { afb_event_unref(event_); event_ = nullptr; }
+inline void event::unref() { if (event_) { afb_event_unref(event_); } event_ = nullptr; }
 inline void event::addref() { afb_event_addref(event_); }
 inline const char *event::name() const { return afb_event_name(event_); }