2 * Copyright (C) 2016, 2017 "IoT.bzh"
3 * Author: José Bollo <jose.bollo@iot.bzh>
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
20 #if !defined(_GNU_SOURCE)
21 # error "_GNU_SOURCE must be defined for using vasprintf"
28 #include "afb-event-itf.h"
30 /* avoid inclusion of <json-c/json.h> */
34 * Describes an argument (or parameter) of a request
37 const char *name; /* name of the argument or NULL if invalid */
38 const char *value; /* string representation of the value of the argument */
39 /* original filename of the argument if path != NULL */
40 const char *path; /* if not NULL, path of the received file for the argument */
41 /* when the request is finalized this file is removed */
45 * Interface for handling requests.
46 * It records the functions to be called for the request.
47 * Don't use this structure directly.
48 * Use the helper functions documented below.
51 /* CAUTION: respect the order, add at the end */
53 struct json_object *(*json)(void *closure);
54 struct afb_arg (*get)(void *closure, const char *name);
56 void (*success)(void *closure, struct json_object *obj, const char *info);
57 void (*fail)(void *closure, const char *status, const char *info);
59 const char *(*raw)(void *closure, size_t *size);
60 void (*send)(void *closure, const char *buffer, size_t size);
62 void *(*context_get)(void *closure);
63 void (*context_set)(void *closure, void *value, void (*free_value)(void*));
65 void (*addref)(void *closure);
66 void (*unref)(void *closure);
68 void (*session_close)(void *closure);
69 int (*session_set_LOA)(void *closure, unsigned level);
71 int (*subscribe)(void *closure, struct afb_event event);
72 int (*unsubscribe)(void *closure, struct afb_event event);
74 void (*subcall)(void *closure, const char *api, const char *verb, struct json_object *args, void (*callback)(void*, int, struct json_object*), void *cb_closure);
75 int (*subcallsync)(void *closure, const char *api, const char *verb, struct json_object *args, struct json_object **result);
79 * Describes the request by bindings from afb-daemon
82 const struct afb_req_itf *itf; /* the interface to use */
83 void *closure; /* the closure argument for functions of 'itf' */
87 * Checks wether the request 'req' is valid or not.
89 * Returns 0 if not valid or 1 if valid.
91 static inline int afb_req_is_valid(struct afb_req req)
93 return req.itf != NULL;
97 * Gets from the request 'req' the argument of 'name'.
98 * Returns a PLAIN structure of type 'struct afb_arg'.
99 * When the argument of 'name' is not found, all fields of result are set to NULL.
100 * When the argument of 'name' is found, the fields are filled,
101 * in particular, the field 'result.name' is set to 'name'.
103 * There is a special name value: the empty string.
104 * The argument of name "" is defined only if the request was made using
105 * an HTTP POST of Content-Type "application/json". In that case, the
106 * argument of name "" receives the value of the body of the HTTP request.
108 static inline struct afb_arg afb_req_get(struct afb_req req, const char *name)
110 return req.itf->get(req.closure, name);
114 * Gets from the request 'req' the string value of the argument of 'name'.
115 * Returns NULL if when there is no argument of 'name'.
116 * Returns the value of the argument of 'name' otherwise.
118 * Shortcut for: afb_req_get(req, name).value
120 static inline const char *afb_req_value(struct afb_req req, const char *name)
122 return afb_req_get(req, name).value;
126 * Gets from the request 'req' the path for file attached to the argument of 'name'.
127 * Returns NULL if when there is no argument of 'name' or when there is no file.
128 * Returns the path of the argument of 'name' otherwise.
130 * Shortcut for: afb_req_get(req, name).path
132 static inline const char *afb_req_path(struct afb_req req, const char *name)
134 return afb_req_get(req, name).path;
138 * Gets from the request 'req' the json object hashing the arguments.
139 * The returned object must not be released using 'json_object_put'.
141 static inline struct json_object *afb_req_json(struct afb_req req)
143 return req.itf->json(req.closure);
147 * Sends a reply of kind success to the request 'req'.
148 * The status of the reply is automatically set to "success".
149 * Its send the object 'obj' (can be NULL) with an
150 * informationnal comment 'info (can also be NULL).
152 * For convenience, the function calls 'json_object_put' for 'obj'.
153 * Thus, in the case where 'obj' should remain available after
154 * the function returns, the function 'json_object_get' shall be used.
156 static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info)
158 req.itf->success(req.closure, obj, info);
162 * Same as 'afb_req_success' but the 'info' is a formatting
163 * string followed by arguments.
165 * For convenience, the function calls 'json_object_put' for 'obj'.
166 * Thus, in the case where 'obj' should remain available after
167 * the function returns, the function 'json_object_get' shall be used.
169 static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...)
173 va_start(args, info);
174 if (info == NULL || vasprintf(&message, info, args) < 0)
177 afb_req_success(req, obj, message);
182 * Sends a reply of kind failure to the request 'req'.
183 * The status of the reply is set to 'status' and an
184 * informationnal comment 'info' (can also be NULL) can be added.
186 * Note that calling afb_req_fail("success", info) is equivalent
187 * to call afb_req_success(NULL, info). Thus even if possible it
188 * is strongly recommanded to NEVER use "success" for status.
190 * For convenience, the function calls 'json_object_put' for 'obj'.
191 * Thus, in the case where 'obj' should remain available after
192 * the function returns, the function 'json_object_get' shall be used.
194 static inline void afb_req_fail(struct afb_req req, const char *status, const char *info)
196 req.itf->fail(req.closure, status, info);
200 * Same as 'afb_req_fail' but the 'info' is a formatting
201 * string followed by arguments.
203 * For convenience, the function calls 'json_object_put' for 'obj'.
204 * Thus, in the case where 'obj' should remain available after
205 * the function returns, the function 'json_object_get' shall be used.
207 static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...)
211 va_start(args, info);
212 if (info == NULL || vasprintf(&message, info, args) < 0)
215 afb_req_fail(req, status, message);
220 * Gets the pointer stored by the binding for the session of 'req'.
221 * When the binding has not yet recorded a pointer, NULL is returned.
223 static inline void *afb_req_context_get(struct afb_req req)
225 return req.itf->context_get(req.closure);
229 * Stores for the binding the pointer 'context' to the session of 'req'.
230 * The function 'free_context' will be called when the session is closed
231 * or if binding stores an other pointer.
233 static inline void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*))
235 req.itf->context_set(req.closure, context, free_context);
239 * Gets the pointer stored by the binding for the session of 'req'.
240 * If the stored pointer is NULL, indicating that no pointer was
241 * already stored, afb_req_context creates a new context by calling
242 * the function 'create_context' and stores it with the freeing function
245 static inline void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*))
247 void *result = afb_req_context_get(req);
248 if (result == NULL) {
249 result = create_context();
250 afb_req_context_set(req, result, free_context);
256 * Frees the pointer stored by the binding for the session of 'req'
257 * and sets it to NULL.
259 * Shortcut for: afb_req_context_set(req, NULL, NULL)
261 static inline void afb_req_context_clear(struct afb_req req)
263 afb_req_context_set(req, NULL, NULL);
267 * Adds one to the count of references of 'req'.
268 * This function MUST be called by asynchronous implementations
269 * of verbs if no reply was sent before returning.
271 static inline void afb_req_addref(struct afb_req req)
273 req.itf->addref(req.closure);
277 * Substracts one to the count of references of 'req'.
278 * This function MUST be called by asynchronous implementations
279 * of verbs after sending the asynchronous reply.
281 static inline void afb_req_unref(struct afb_req req)
283 req.itf->unref(req.closure);
287 * Closes the session associated with 'req'
288 * and delete all associated contexts.
290 static inline void afb_req_session_close(struct afb_req req)
292 req.itf->session_close(req.closure);
296 * Sets the level of assurance of the session of 'req'
297 * to 'level'. The effect of this function is subject of
299 * Returns 1 on success or 0 if failed.
301 static inline int afb_req_session_set_LOA(struct afb_req req, unsigned level)
303 return req.itf->session_set_LOA(req.closure, level);
307 * Stores 'req' on heap for asynchrnous use.
308 * Returns a pointer to the stored 'req' or NULL on memory depletion.
309 * The count of reference to 'req' is incremented on success
310 * (see afb_req_addref).
312 static inline struct afb_req *afb_req_store(struct afb_req req)
314 struct afb_req *result = (struct afb_req*)malloc(sizeof *result);
315 if (result != NULL) {
323 * Retrieves the afb_req stored at 'req' and frees the memory.
324 * Returns the stored request.
325 * The count of reference is UNCHANGED, thus, normally, the
326 * function 'afb_req_unref' should be called on the result
327 * after that the asynchronous reply if sent.
329 static inline struct afb_req afb_req_unstore(struct afb_req *req)
331 struct afb_req result = *req;
337 * Establishes for the client link identified by 'req' a subscription
339 * Returns 0 in case of successful subscription or -1 in case of error.
341 static inline int afb_req_subscribe(struct afb_req req, struct afb_event event)
343 return req.itf->subscribe(req.closure, event);
347 * Revokes the subscription established to the 'event' for the client
348 * link identified by 'req'.
349 * Returns 0 in case of successful subscription or -1 in case of error.
351 static inline int afb_req_unsubscribe(struct afb_req req, struct afb_event event)
353 return req.itf->unsubscribe(req.closure, event);
357 * Makes a call to the method of name 'api' / 'verb' with the object 'args'.
358 * This call is made in the context of the request 'req'.
359 * On completion, the function 'callback' is invoked with the
360 * 'closure' given at call and two other parameters: 'iserror' and 'result'.
361 * 'iserror' is a boolean that indicates if the reply is an error reply.
362 * 'result' is the json object of the reply.
364 static inline void afb_req_subcall(struct afb_req req, const char *api, const char *verb, struct json_object *args, void (*callback)(void *closure, int iserror, struct json_object *result), void *closure)
366 req.itf->subcall(req.closure, api, verb, args, callback, closure);
370 * Makes a call to the method of name 'api' / 'verb' with the object 'args'.
371 * This call is made in the context of the request 'req'.
372 * This call is synchronous, it waits untill completion of the request.
373 * It returns 0 on an error answer and returns 1 when no error was detected.
374 * The object pointed by 'result' is filled and must be released by the caller
375 * after its use by calling 'json_object_put'.
377 static inline int afb_req_subcall_sync(struct afb_req req, const char *api, const char *verb, struct json_object *args, struct json_object **result)
379 return req.itf->subcallsync(req.closure, api, verb, args, result);
383 static inline const char *afb_req_raw(struct afb_req req, size_t *size)
385 return req.itf->raw(req.closure, size);
389 static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size)
391 req.itf->send(req.closure, buffer, size);