improves websockets

Change-Id: I5b941a043838d438c0acc31623ce9361fa742f35
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

1 files changed, 388 insertions, 0 deletions

diff --git a/src/afb-ws.c b/src/afb-ws.c
new file mode 100644
index 00000000..e82e96fc
--- /dev/null
+++ b/src/afb-ws.c
@@ -0,0 +1,388 @@
+/*
+ * Copyright 2016 IoT.bzh
+ * Author: José Bollo <jose.bollo@iot.bzh>
+ *
+ * Inspired by the work of 
+ *
+ * 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 <assert.h>
+#include <errno.h>
+#include <sys/uio.h>
+#include <string.h>
+
+#include <json.h>
+
+#include "websock.h"
+
+#include "utils-upoll.h"
+
+static ssize_t aws_writev(struct afb_ws *ws, const struct iovec *iov, int iovcnt);
+static ssize_t aws_readv(struct afb_ws *ws, const struct iovec *iov, int iovcnt);
+static void aws_disconnect(struct afb_ws *ws);
+static void aws_on_close(struct afb_ws *ws, uint16_t code, size_t size);
+static void aws_on_content(struct afb_ws *ws, int last, size_t size);
+static void aws_on_readable(struct afb_ws *ws);
+
+static struct websock_itf aws_itf = {
+	.writev = (void*)aws_writev,
+	.readv = (void*)aws_readv,
+	.disconnect = (void*)aws_disconnect,
+
+	.on_ping = NULL,
+	.on_pong = NULL,
+	.on_close = (void*)aws_on_close,
+	.on_text = (void*)aws_on_content,
+	.on_binary = (void*)aws_on_content,
+	.on_continue = (void*)aws_on_content,
+	.on_extension = NULL,
+};
+
+struct afb_wsreq
+{
+	struct afb_ws *aws;
+	struct afb_wsreq *next;
+	struct json_object *id;
+	struct json_object *name;
+	struct json_object *token;
+	struct json_object *request;
+};
+
+struct afb_ws
+{
+	int fd;
+	struct upoll *up;
+	struct websock *ws;
+	void (*cleanup)(void*);
+	void *cleanup_closure;
+	struct AFB_clientCtx *context;
+	struct afb_wsreq *requests;
+};
+
+static struct afb_arg wsreq_get(struct afb_wsreq *wsreq, const char *name);
+static void wsreq_iterate(struct afb_wsreq *wsreq, int (*iterator)(void *closure, struct afb_arg arg), void *closure);
+static void wsreq_fail(struct afb_wsreq *wsreq, const char *status, const char *info);
+static void wsreq_success(struct afb_wsreq *wsreq, struct json_object *obj, const char *info);
+static int wsreq_session_create(struct afb_wsreq *wsreq);
+static int wsreq_session_check(struct afb_wsreq *wsreq, int refresh);
+static void wsreq_session_close(struct afb_wsreq *wsreq);
+
+static const struct afb_req_itf wsreq_itf = {
+	.get = (void*)wsreq_get,
+	.iterate = (void*)wsreq_iterate,
+	.fail = (void*)wsreq_fail,
+	.success = (void*)wsreq_success,
+	.session_create = (void*)wsreq_session_create,
+	.session_check = (void*)wsreq_session_check,
+	.session_close = (void*)wsreq_session_close
+};
+
+struct afb_ws *afb_ws_create(int fd, struct AFB_clientCtx *context, void (*cleanup)(void*), void *closure)
+{
+	struct afb_ws *result;
+
+	assert(fd >= 0);
+	assert(context != NULL);
+
+	result = malloc(sizeof * result);
+	if (result == NULL)
+		goto error;
+
+	result->fd = fd;
+	result->cleanup = cleanup;
+	result->cleanup_closure = closure;
+	result->context = ctxClientGet(context);
+	if (result->context == NULL)
+		goto error2;
+
+	result->ws = websock_create_v13(&aws_itf, result);
+	if (result->ws == NULL)
+		goto error3;
+
+	result->up = upoll_open(result->fd, result);
+	if (result->up == NULL)
+		goto error4;
+
+	upoll_on_readable(result->up, (void*)aws_on_readable);
+	upoll_on_hangup(result->up, (void*)aws_disconnect);
+	return result;
+error4:
+	websock_destroy(result->ws);
+error3:
+	ctxClientPut(result->context);
+error2:
+	free(result);
+error:
+	close(fd);
+	return NULL;
+}
+
+static ssize_t aws_writev(struct afb_ws *ws, const struct iovec *iov, int iovcnt)
+{
+	ssize_t rc;
+	do {
+		rc = writev(ws->fd, iov, iovcnt);
+	} while(rc == -1 && errno == EINTR);
+	return rc;
+}
+
+static ssize_t aws_readv(struct afb_ws *ws, const struct iovec *iov, int iovcnt)
+{
+	ssize_t rc;
+	do {
+		rc = readv(ws->fd, iov, iovcnt);
+	} while(rc == -1 && errno == EINTR);
+	return rc;
+}
+
+static void aws_disconnect(struct afb_ws *ws)
+{
+	upoll_close(ws->up);
+	websock_destroy(ws->ws);
+	close(ws->fd);
+	MHD_resume_connection (ws->connection);
+	ctxClientPut(ws->context);
+	json_tokener_free(ws->tokener);
+	free(ws);
+}
+
+static void aws_on_close(struct afb_ws *ws, uint16_t code, size_t size)
+{
+	/* do nothing */
+}
+
+static void aws_on_readable(struct afb_ws *ws)
+{
+	websock_dispatch(ws->ws);
+}
+
+static int aws_handle_json(struct afb_ws *aws, struct json_object *obj)
+{
+	struct afb_req r;
+	int count, num;
+	struct json_object *type, *id, *name, *req, *token;
+	struct afb_wsreq *wsreq;
+	const char *api, *verb;
+	size_t lenapi, lenverb;
+
+	/* protocol inspired by http://www.gir.fr/ocppjs/ocpp_srpc_spec.shtml */
+
+	/* the object must be an array of 4 or 5 elements */
+	if (!json_object_is_type(obj, json_type_array))
+		goto error;
+	count = json_object_array_length(obj);
+	if (count < 4 || count > 5)
+		goto error;
+
+	/* get the 5 elements: type id name request token */
+	type = json_object_array_get_idx(obj, 0);
+	id = json_object_array_get_idx(obj, 1);
+	name = json_object_array_get_idx(obj, 2);
+	req = json_object_array_get_idx(obj, 3);
+	token = json_object_array_get_idx(obj, 4);
+
+	/* check the types: int string string object string */
+	if (!json_object_is_type(type, json_type_int))
+		goto error;
+	if (!json_object_is_type(id, json_type_string))
+		goto error;
+	if (!json_object_is_type(name, json_type_string))
+		goto error;
+	if (!json_object_is_type(req, json_type_object))
+		goto error;
+	if (token != NULL && !json_object_is_type(token, json_type_string))
+		goto error;
+
+	/* the type is only 2 */
+	num = json_object_get_int(type);
+	if (num != 2)
+		goto error;
+
+	/* checks the api/verb structure of name */
+	api = json_object_get_string(name);
+	for (lenapi = 0 ; api[lenapi] && api[lenapi] != '/' ; lenapi++);
+	if (!lenapi || !api[lenapi])
+		goto error;
+	verb = &api[lenapi+1];
+	for (lenverb = 0 ; verb[lenverb] && verb[lenverb] != '/' ; lenverb++);
+	if (!lenverb || verb[lenverb])
+		goto error;
+
+	/* allocates the request data */
+	wsreq = malloc(sizeof *wsreq);
+	if (wsreq == NULL)
+		goto error;
+
+	/* fill and record the request */
+	wsreq->aws = aws;
+	wsreq->id = json_object_get(id);
+	wsreq->name = json_object_get(name);
+	wsreq->token = json_object_get(token);
+	wsreq->request = json_object_get(req);
+	wsreq->next = aws->requests;
+	aws->requests = wsreq;
+	json_object_put(obj);
+
+	r.data = wsreq;
+	r.itf = &wsreq_itf;
+	afb_apis_call(r, aws->context, api, lenapi, verb, lenverb);
+	return 1;
+
+error:
+	json_object_put(obj);
+	return 0;
+}
+
+static void aws_on_content(struct afb_ws *ws, int last, size_t size)
+{
+	ssize_t rrc;
+	char buffer[8000];
+	struct json_object *obj;
+
+	json_tokener_reset(ws->tokener);
+	while(size) {
+		rrc = websock_read(ws->ws, buffer,
+				size > sizeof buffer ? sizeof buffer : size);
+		if (rrc < 0) {
+			websock_close(ws->ws);
+			return;
+		}
+		size -= (size_t)rrc;
+		obj = json_tokener_parse_ex(ws->tokener, buffer, (int)rrc);
+		if (obj != NULL) {
+			if (!aws_handle_json(ws, obj)) {
+				websock_close(ws->ws);
+				return;
+			}
+		} else if (json_tokener_get_error(ws->tokener) != json_tokener_continue) {
+			websock_close(ws->ws);
+			return;
+		}
+	}
+}
+
+static struct afb_arg wsreq_get(struct afb_wsreq *wsreq, const char *name)
+{
+	struct afb_arg arg;
+	struct json_object *value;
+
+	if (json_object_object_get_ex(wsreq->request, name, &value)) {
+		arg.name = name;
+		arg.value = json_object_get_string(value);
+		arg.size = strlen(arg.value);
+	} else {
+		arg.name = NULL;
+		arg.value = NULL;
+		arg.size = 0;
+	}
+	arg.path = NULL;
+	return arg;
+}
+
+static void wsreq_iterate(struct afb_wsreq *wsreq, int (*iterator)(void *closure, struct afb_arg arg), void *closure)
+{
+	struct afb_arg arg;
+	struct json_object_iterator it = json_object_iter_begin(wsreq->request);
+	struct json_object_iterator end = json_object_iter_end(wsreq->request);
+
+	arg.size = 0;
+	arg.path = NULL;
+	while(!json_object_iter_equal(&it, &end)) {
+		arg.name = json_object_iter_peek_name(&it);
+		arg.value = json_object_get_string(json_object_iter_peek_value(&it));
+		if (!iterator(closure, arg))
+			break;
+		json_object_iter_next(&it);
+	}
+}
+
+static int wsreq_session_create(struct afb_wsreq *wsreq)
+{
+	struct AFB_clientCtx *context = wsreq->aws->context;
+	if (context->created)
+		return 0;
+	return wsreq_session_check(wsreq, 1);
+}
+
+static int wsreq_session_check(struct afb_wsreq *wsreq, int refresh)
+{
+	const char *token;
+	struct AFB_clientCtx *context = wsreq->aws->context;
+
+	if (wsreq->token == NULL)
+		return 0;
+
+	token = json_object_get_string(wsreq->token);
+	if (token == NULL)
+		return 0;
+
+	if (!ctxTokenCheck (context, token))
+		return 0;
+
+	if (refresh) {
+		ctxTokenNew (context);
+	}
+
+	return 1;
+}
+
+static void wsreq_session_close(struct afb_wsreq *wsreq)
+{
+	struct AFB_clientCtx *context = wsreq->aws->context;
+	ctxClientClose(context);
+}
+
+
+static void wsreq_reply(struct afb_wsreq *wsreq, int retcode, const char *status, const char *info, json_object *resp)
+{
+	json_object *root, *request, *reply;
+	const char *message;
+
+	/* builds the answering structure */
+	root = json_object_new_object();
+	json_object_object_add(root, "jtype", json_object_new_string("afb-reply"));
+	request = json_object_new_object();
+	json_object_object_add(root, "request", request);
+	json_object_object_add(request, "status", json_object_new_string(status));
+	if (info)
+		json_object_object_add(request, "info", json_object_new_string(info));
+	if (resp)
+		json_object_object_add(root, "response", resp);
+
+	/* make the reply */
+	reply = json_object_new_array();
+	json_object_array_add(reply, json_object_new_int(retcode));
+	json_object_array_add(reply, wsreq->id);
+	json_object_array_add(reply, root);
+	json_object_array_add(reply, json_object_new_string(wsreq->aws->context->token));
+
+	/* emits the reply */
+	message = json_object_to_json_string(reply);
+	websock_text(wsreq->aws->ws, message, strlen(message));
+	json_object_put(reply);
+
+	/* TODO eliminates the wsreq */
+}
+
+static void wsreq_fail(struct afb_wsreq *wsreq, const char *status, const char *info)
+{
+	wsreq_reply(wsreq, 4, status, info, NULL);
+}
+
+static void wsreq_success(struct afb_wsreq *wsreq, json_object *obj, const char *info)
+{
+	wsreq_reply(wsreq, 3, "success", info, obj);
+}
+