2 * Copyright (C) 2016 "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/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);
78 * Describes the request by plugins from afb-daemon
81 const struct afb_req_itf *itf; /* the interface to use */
82 void *closure; /* the closure argument for functions of 'itf' */
86 * Gets from the request 'req' the argument of 'name'.
87 * Returns a PLAIN structure of type 'struct afb_arg'.
88 * When the argument of 'name' is not found, all fields of result are set to NULL.
89 * When the argument of 'name' is found, the fields are filled,
90 * in particular, the field 'result.name' is set to 'name'.
92 * There is a special name value: the empty string.
93 * The argument of name "" is defined only if the request was made using
94 * an HTTP POST of Content-Type "application/json". In that case, the
95 * argument of name "" receives the value of the body of the HTTP request.
97 static inline struct afb_arg afb_req_get(struct afb_req req, const char *name)
99 return req.itf->get(req.closure, name);
103 * Gets from the request 'req' the string value of the argument of 'name'.
104 * Returns NULL if when there is no argument of 'name'.
105 * Returns the value of the argument of 'name' otherwise.
107 * Shortcut for: afb_req_get(req, name).value
109 static inline const char *afb_req_value(struct afb_req req, const char *name)
111 return afb_req_get(req, name).value;
115 * Gets from the request 'req' the path for file attached to the argument of 'name'.
116 * Returns NULL if when there is no argument of 'name' or when there is no file.
117 * Returns the path of the argument of 'name' otherwise.
119 * Shortcut for: afb_req_get(req, name).path
121 static inline const char *afb_req_path(struct afb_req req, const char *name)
123 return afb_req_get(req, name).path;
127 * Gets from the request 'req' the json object hashing the arguments.
128 * The returned object must not be released using 'json_object_put'.
130 static inline struct json_object *afb_req_json(struct afb_req req)
132 return req.itf->json(req.closure);
136 * Sends a reply of kind success to the request 'req'.
137 * The status of the reply is automatically set to "success".
138 * Its send the object 'obj' (can be NULL) with an
139 * informationnal comment 'info (can also be NULL).
141 * For conveniency, the function calls 'json_object_put' for 'obj'.
142 * Thus, in the case where 'obj' should remain available after
143 * the function returns, the function 'json_object_get' shall be used.
145 static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info)
147 req.itf->success(req.closure, obj, info);
151 * Same as 'afb_req_success' but the 'info' is a formatting
152 * string followed by arguments.
154 * For conveniency, the function calls 'json_object_put' for 'obj'.
155 * Thus, in the case where 'obj' should remain available after
156 * the function returns, the function 'json_object_get' shall be used.
158 static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...)
162 va_start(args, info);
163 if (info == NULL || vasprintf(&message, info, args) < 0)
166 afb_req_success(req, obj, message);
171 * Sends a reply of kind failure to the request 'req'.
172 * The status of the reply is set to 'status' and an
173 * informationnal comment 'info' (can also be NULL) can be added.
175 * Note that calling afb_req_fail("success", info) is equivalent
176 * to call afb_req_success(NULL, info). Thus even if possible it
177 * is strongly recommanded to NEVER use "success" for status.
179 * For conveniency, the function calls 'json_object_put' for 'obj'.
180 * Thus, in the case where 'obj' should remain available after
181 * the function returns, the function 'json_object_get' shall be used.
183 static inline void afb_req_fail(struct afb_req req, const char *status, const char *info)
185 req.itf->fail(req.closure, status, info);
189 * Same as 'afb_req_fail' but the 'info' is a formatting
190 * string followed by arguments.
192 * For conveniency, the function calls 'json_object_put' for 'obj'.
193 * Thus, in the case where 'obj' should remain available after
194 * the function returns, the function 'json_object_get' shall be used.
196 static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...)
200 va_start(args, info);
201 if (info == NULL || vasprintf(&message, info, args) < 0)
204 afb_req_fail(req, status, message);
209 * Gets the pointer stored by the plugin for the session of 'req'.
210 * When the plugin has not yet recorded a pointer, NULL is returned.
212 static inline void *afb_req_context_get(struct afb_req req)
214 return req.itf->context_get(req.closure);
218 * Stores for the plugin the pointer 'context' to the session of 'req'.
219 * The function 'free_context' will be called when the session is closed
220 * or if plugin stores an other pointer.
222 static inline void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*))
224 req.itf->context_set(req.closure, context, free_context);
228 * Gets the pointer stored by the plugin for the session of 'req'.
229 * If the stored pointer is NULL, indicating that no pointer was
230 * already stored, afb_req_context creates a new context by calling
231 * the function 'create_context' and stores it with the freeing function
234 static inline void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*))
236 void *result = afb_req_context_get(req);
237 if (result == NULL) {
238 result = create_context();
239 afb_req_context_set(req, result, free_context);
245 * Frees the pointer stored by the plugin for the session of 'req'
246 * and sets it to NULL.
248 * Shortcut for: afb_req_context_set(req, NULL, NULL)
250 static inline void afb_req_context_clear(struct afb_req req)
252 afb_req_context_set(req, NULL, NULL);
256 * Adds one to the count of references of 'req'.
257 * This function MUST be called by asynchronous implementations
258 * of verbs if no reply was sent before returning.
260 static inline void afb_req_addref(struct afb_req req)
262 req.itf->addref(req.closure);
266 * Substracts one to the count of references of 'req'.
267 * This function MUST be called by asynchronous implementations
268 * of verbs after sending the asynchronous reply.
270 static inline void afb_req_unref(struct afb_req req)
272 req.itf->unref(req.closure);
276 * Closes the session associated with 'req'
277 * and delete all associated contexts.
279 static inline void afb_req_session_close(struct afb_req req)
281 req.itf->session_close(req.closure);
285 * Sets the level of assurance of the session of 'req'
286 * to 'level'. The effect of this function is subject of
288 * Returns 1 on success or 0 if failed.
290 static inline int afb_req_session_set_LOA(struct afb_req req, unsigned level)
292 return req.itf->session_set_LOA(req.closure, level);
296 * Stores 'req' on heap for asynchrnous use.
297 * Returns a pointer to the stored 'req' or NULL on memory depletion.
298 * The count of reference to 'req' is incremented on success
299 * (see afb_req_addref).
301 static inline struct afb_req *afb_req_store(struct afb_req req)
303 struct afb_req *result = malloc(sizeof *result);
304 if (result != NULL) {
312 * Retrieves the afb_req stored at 'req' and frees the memory.
313 * Returns the stored request.
314 * The count of reference is UNCHANGED, thus, normally, the
315 * function 'afb_req_unref' should be called on the result
316 * after that the asynchronous reply if sent.
318 static inline struct afb_req afb_req_unstore(struct afb_req *req)
320 struct afb_req result = *req;
326 * Establishes for the client link identified by 'req' a subscription
328 * Returns 0 in case of successful subscription or -1 in case of error.
330 static inline int afb_req_subscribe(struct afb_req req, struct afb_event event)
332 return req.itf->subscribe(req.closure, event);
336 * Revokes the subscription established to the 'event' for the client
337 * link identified by 'req'.
338 * Returns 0 in case of successful subscription or -1 in case of error.
340 static inline int afb_req_unsubscribe(struct afb_req req, struct afb_event event)
342 return req.itf->unsubscribe(req.closure, event);
346 * Makes a call to the method of name 'api' / 'verb' with the object 'args'.
347 * This call is made in the context of the request 'req'.
348 * On completion, the function 'callback' is invoked with the
349 * 'closure' given at call and two other parameters: 'iserror' and 'result'.
350 * 'iserror' is a boolean that indicates if the reply is an error reply.
351 * 'result' is the json object of the reply.
353 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)
355 req.itf->subcall(req.closure, api, verb, args, callback, closure);
359 static inline const char *afb_req_raw(struct afb_req req, size_t *size)
361 return req.itf->raw(req.closure, size);
365 static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size)
367 req.itf->send(req.closure, buffer, size);