adding jbus

Change-Id: Ia712f77d32e3a7b0b15fcf2066b562d8d4c02169

2 files changed, 433 insertions, 0 deletions

diff --git a/src/utils-jbus.c b/src/utils-jbus.c
new file mode 100644
index 0000000..8c48113
--- /dev/null
+++ b/src/utils-jbus.c
@@ -0,0 +1,402 @@
+/*
+ Copyright 2015 IoT.bzh
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#include <json.h>
+#include <dbus/dbus.h>
+
+#include "utils-jbus.h"
+
+struct jreq;
+struct jservice;
+struct jbus;
+
+struct jreq {
+	DBusConnection *connection;
+	DBusMessage *reply;
+};
+
+struct jservice {
+	struct jservice *next;
+	char *method;
+	void (*oncall)(struct jreq *, struct json_object *);
+};
+
+struct jrespw {
+	struct jrespw *next;
+	dbus_uint32_t serial;
+	void *data;
+	void (*onresp)(int status, struct json_object *response, void *data);
+};
+
+struct jbus {
+	int refcount;
+	struct jservice *services;
+	DBusConnection *connection;
+	struct jrespw *waiters;
+	char *path;
+	char *name;
+};
+
+static const char reply_out_of_memory[] = "{\"status\":\"out of memory\"}";
+static const char reply_invalid[] = "{\"status\":\"invalid request\"}";
+static const char interface_jbus[] = "org.jbus";
+
+static int send_reply(struct jreq *jreq, const char *reply)
+{
+	int rc = -1;
+	if (dbus_message_append_args(jreq->reply, DBUS_TYPE_STRING, &reply, DBUS_TYPE_INVALID)) {
+		if (dbus_connection_send(jreq->connection, jreq->reply, NULL))
+			rc = 0;
+	}
+	dbus_message_unref(jreq->reply);
+	dbus_connection_unref(jreq->connection);
+	free(jreq);
+	return rc;
+}
+
+static DBusHandlerResult incoming_resp(DBusConnection *connection, DBusMessage *message, struct jbus *jbus)
+{
+	int status;
+	const char *str;
+	struct jrespw *jrw, **prv;
+	struct json_object *reply;
+	dbus_uint32_t serial;
+
+	/* search for the waiter */
+	serial = dbus_message_get_serial(message);
+	prv = &jbus->waiters;
+	while ((jrw = *prv) != NULL && jrw->serial != serial)
+		prv = &jrw->next;
+	if (jrw == NULL)
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+	*prv = jrw->next;
+
+	/* retrieve the json value */
+	if (!dbus_message_get_args(message, NULL, DBUS_TYPE_STRING, &str, DBUS_TYPE_INVALID)) {
+		status = -1;
+		reply = NULL;
+	} else {
+		reply = json_tokener_parse(str);
+		status = reply ? 0 : -1;
+	}
+
+	/* treat it */
+	jrw->onresp(status, reply, jrw->data);
+	free(jrw);
+	return DBUS_HANDLER_RESULT_HANDLED;
+}
+
+static int matchitf(DBusMessage *message)
+{
+	const char *itf = dbus_message_get_interface(message);
+	return itf != NULL && !strcmp(itf, interface_jbus);
+}
+
+static DBusHandlerResult incoming_call(DBusConnection *connection, DBusMessage *message, struct jbus *jbus)
+{
+	struct jservice *srv;
+	struct jreq *jreq;
+	const char *str;
+	const char *method;
+	struct json_object *query;
+
+	/* search for the service */
+	if (!matchitf(message))
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+	method = dbus_message_get_member(message);
+	if (method == NULL)
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+	srv = jbus->services;
+	while(srv != NULL && strcmp(method, srv->method))
+		srv = srv->next;
+	if (srv == NULL)
+		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+
+	/* handle the message */
+	jreq = malloc(sizeof * jreq);
+	if (jreq == NULL)
+		return DBUS_HANDLER_RESULT_NEED_MEMORY;
+	jreq->reply = dbus_message_new_method_return(message);
+	if (jreq->reply == NULL) {
+		free(jreq);
+		return DBUS_HANDLER_RESULT_NEED_MEMORY;
+	}
+	jreq->connection = dbus_connection_ref(jbus->connection);
+	
+	/* retrieve the json value */
+	if (!dbus_message_get_args(message, NULL, DBUS_TYPE_STRING, &str, DBUS_TYPE_INVALID)) {
+		send_reply(jreq, reply_invalid);
+		return DBUS_HANDLER_RESULT_HANDLED;
+	}
+	query = json_tokener_parse(str);
+	if (query == NULL) {
+		send_reply(jreq, reply_invalid);
+		return DBUS_HANDLER_RESULT_HANDLED;
+	}
+
+	/* treat it */
+	srv->oncall(jreq, query);
+	return DBUS_HANDLER_RESULT_HANDLED;
+}
+
+static DBusHandlerResult incoming(DBusConnection *connection, DBusMessage *message, void *data)
+{
+	switch(dbus_message_get_type(message)) {
+	case DBUS_MESSAGE_TYPE_METHOD_CALL:
+		return incoming_call(connection, message, (struct jbus*)data);
+	case  DBUS_MESSAGE_TYPE_METHOD_RETURN:
+		return incoming_resp(connection, message, (struct jbus*)data);
+	}
+	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
+}
+
+
+struct jbus *create_jbus(int session, const char *path)
+{
+	struct jbus *jbus;
+	char *name;
+
+	/* create the context and connect */
+	jbus = calloc(1, sizeof * jbus);
+	if (jbus == NULL) {
+		errno = ENOMEM;
+		goto error;
+	}
+	jbus->refcount = 1;
+	jbus->path = strdup(path);
+	jbus->name = NULL;
+	if (jbus->path == NULL) {
+		errno = ENOMEM;
+		goto error2;
+	}
+	while(*path == '/') path++;
+	jbus->name = name = strdup(path);
+	if (name == NULL) {
+		errno = ENOMEM;
+		goto error2;
+	}
+	while(*name) {
+		if (*name == '/')
+			*name = '.';
+		name++;
+	}
+	name--;
+	while (name >= jbus->name && *name == '.')
+		*name-- = 0;
+	if (!*jbus->name) {
+		errno = EINVAL;
+		goto error2;
+	}
+
+	/* connect */
+	jbus->connection = dbus_bus_get(session ? DBUS_BUS_SESSION : DBUS_BUS_SYSTEM, NULL);
+	if (jbus->connection == NULL) {
+		goto error2;
+	}
+	if (!dbus_connection_add_filter(jbus->connection, incoming, jbus, NULL)) {
+		goto error2;
+	}
+
+	return jbus;
+
+error2:
+	jbus_unref(jbus);
+error:
+	return NULL;
+}
+
+void jbus_addref(struct jbus *jbus)
+{
+	jbus->refcount++;
+}
+
+void jbus_unref(struct jbus *jbus)
+{
+	struct jservice *srv;
+	if (!--jbus->refcount) {
+		dbus_connection_unref(jbus->connection);
+		while((srv = jbus->services) != NULL) {
+			jbus->services = srv->next;
+			free(srv->method);
+			free(srv);
+		}
+		free(jbus->name);
+		free(jbus->path);
+		free(jbus);
+	}
+}
+
+int jbus_reply(struct jreq *jreq, struct json_object *reply)
+{
+	const char *str = json_object_to_json_string(reply);
+	return send_reply(jreq, str ? str : reply_out_of_memory);
+}
+
+int jbus_add_service(struct jbus *jbus, const char *method, void (*oncall)(struct jreq *jreq, struct json_object *request))
+{
+	struct jservice *srv;
+
+	/* allocation */
+	srv = malloc(sizeof * srv);
+	if (srv == NULL) {
+		errno = ENOMEM;
+		goto error;
+	}
+	srv->method = strdup(method);
+	if (!srv->method) {
+		errno = ENOMEM;
+		goto error2;
+	}
+
+	/* record the service */
+	srv->oncall = oncall;
+	srv->next = jbus->services;
+	jbus->services = srv;
+
+	return 0;
+
+error3:
+	free(srv->method);
+error2:
+	free(srv);
+error:
+	return -1;
+}
+
+int jbus_start_serving(struct jbus *jbus)
+{
+	int status = dbus_bus_request_name(jbus->connection, jbus->name, DBUS_NAME_FLAG_DO_NOT_QUEUE, NULL);
+	switch (status) {
+	case DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER:
+	case DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER:
+		return 0;
+	case DBUS_REQUEST_NAME_REPLY_EXISTS:
+	case DBUS_REQUEST_NAME_REPLY_IN_QUEUE:
+		errno = EADDRINUSE;
+		return -1;
+	}
+}
+
+int jbus_callj(struct jbus *jbus, const char *method, const char *query, void (*onresp)(int status, struct json_object *response, void *data), void *data)
+{
+	int rc;
+	DBusMessage *msg;
+	struct jrespw *resp;
+
+	resp = malloc(sizeof * resp);
+	if (resp == NULL) {
+		errno = ENOMEM;
+		goto error;
+	}
+
+	msg = dbus_message_new_method_call(jbus->name, jbus->path, interface_jbus, method);
+	if (msg == NULL) {
+		errno = ENOMEM;
+		goto error2;
+	}
+
+	if (!dbus_message_append_args(msg, DBUS_TYPE_STRING, &query, DBUS_TYPE_INVALID)) {
+		errno = ENOMEM;
+		goto error3;
+	}
+
+	if (!dbus_connection_send(jbus->connection, msg, &resp->serial)) {
+		goto error3;
+	}
+
+	dbus_message_unref(msg);
+	resp->data = data;
+	resp->onresp = onresp;
+	resp->next = jbus->waiters;
+	jbus->waiters = resp;
+	return 0;
+
+error3:
+	dbus_message_unref(msg);
+error2:
+	free(resp);
+error:
+	return -1;
+}
+
+
+int jbus_call(struct jbus *jbus, const char *method, struct json_object *query, void (*onresp)(int status, struct json_object *response, void *data), void *data)
+{
+	const char *str = json_object_to_json_string(query);
+	if (str == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+	return jbus_callj(jbus, method, str, onresp, data);
+}
+
+#ifdef SERVER
+#include <stdio.h>
+#include <unistd.h>
+void ping(struct jreq *jreq, struct json_object *request)
+{
+printf("ping(%s) -> %s\n",json_object_to_json_string(request),json_object_to_json_string(request));
+	jbus_reply(jreq, request);
+	json_object_put(request);
+}
+void incr(struct jreq *jreq, struct json_object *request)
+{
+	static int counter = 0;
+	struct json_object *res = json_object_new_int(++counter);
+printf("incr(%s) -> %s\n",json_object_to_json_string(request),json_object_to_json_string(res));
+	jbus_reply(jreq, res);
+	json_object_put(res);
+	json_object_put(request);
+}
+int main()
+{
+	struct jbus *jbus = create_jbus(1, "/bzh/iot/jdbus");
+	int s1 = jbus_add_service(jbus, "ping", ping);
+	int s2 = jbus_add_service(jbus, "incr", incr);
+	int s3 = jbus_start_serving(jbus);
+	printf("started %d %d %d\n", s1, s2, s3);
+	while (dbus_connection_read_write_dispatch (jbus->connection, -1))
+		;
+}
+#endif
+#ifdef CLIENT
+#include <stdio.h>
+#include <unistd.h>
+void onresp(int status, struct json_object *response, void *data)
+{
+	printf("resp: %d, %s, %s\n",status,(char*)data,json_object_to_json_string(response));
+	json_object_put(response);
+}
+int main()
+{
+	struct jbus *jbus = create_jbus(1, "/bzh/iot/jdbus");
+	int i = 10;
+	while(i--) {
+		jbus_callj(jbus, "ping", "{\"toto\":[1,2,3,4,true,\"toto\"]}", onresp, "ping");
+		jbus_callj(jbus, "incr", "{\"doit\":\"for-me\"}", onresp, "incr");
+		dbus_connection_read_write_dispatch (jbus->connection, 1);
+	}
+	while (dbus_connection_read_write_dispatch (jbus->connection, -1))
+		;
+}
+#endif
+
diff --git a/src/utils-jbus.h b/src/utils-jbus.h
new file mode 100644
index 0000000..f1ec78f
--- /dev/null
+++ b/src/utils-jbus.h
@@ -0,0 +1,31 @@
+/*
+ Copyright 2015 IoT.bzh
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+
+struct jreq;
+struct jbus;
+
+
+struct jbus *create_jbus(int session, const char *path);
+void jbus_addref(struct jbus *jbus);
+void jbus_unref(struct jbus *jbus);
+
+int jbus_reply(struct jreq *jreq, struct json_object *reply);
+int jbus_add_service(struct jbus *jbus, const char *method, void (*oncall)(struct jreq *, struct json_object *));
+
+int jbus_callj(struct jbus *jbus, const char *method, const char *query, void (*onresp)(int, struct json_object *, void *), void *data);
+int jbus_call(struct jbus *jbus, const char *method, struct json_object *query, void (*onresp)(int, struct json_object *response, void *), void *data);
+