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);
76 * Describes the request by plugins from afb-daemon
79 const struct afb_req_itf *itf; /* the interface to use */
80 void *closure; /* the closure argument for functions of 'itf' */
84 * Gets from the request 'req' the argument of 'name'.
85 * Returns a PLAIN structure of type 'struct afb_arg'.
86 * When the argument of 'name' is not found, all fields of result are set to NULL.
87 * When the argument of 'name' is found, the fields are filled,
88 * in particular, the field 'result.name' is set to 'name'.
90 * There is a special name value: the empty string.
91 * The argument of name "" is defined only if the request was made using
92 * an HTTP POST of Content-Type "application/json". In that case, the
93 * argument of name "" receives the value of the body of the HTTP request.
95 static inline struct afb_arg afb_req_get(struct afb_req req, const char *name)
97 return req.itf->get(req.closure, name);
101 * Gets from the request 'req' the string value of the argument of 'name'.
102 * Returns NULL if when there is no argument of 'name'.
103 * Returns the value of the argument of 'name' otherwise.
105 * Shortcut for: afb_req_get(req, name).value
107 static inline const char *afb_req_value(struct afb_req req, const char *name)
109 return afb_req_get(req, name).value;
113 * Gets from the request 'req' the path for file attached to the argument of 'name'.
114 * Returns NULL if when there is no argument of 'name' or when there is no file.
115 * Returns the path of the argument of 'name' otherwise.
117 * Shortcut for: afb_req_get(req, name).path
119 static inline const char *afb_req_path(struct afb_req req, const char *name)
121 return afb_req_get(req, name).path;
125 * Gets from the request 'req' the json object hashing the arguments.
126 * The returned object must not be released using 'json_object_put'.
128 static inline struct json_object *afb_req_json(struct afb_req req)
130 return req.itf->json(req.closure);
134 * Sends a reply of kind success to the request 'req'.
135 * The status of the reply is automatically set to "success".
136 * Its send the object 'obj' (can be NULL) with an
137 * informationnal comment 'info (can also be NULL).
139 * For conveniency, the function calls 'json_object_put' for 'obj'.
140 * Thus, in the case where 'obj' should remain available after
141 * the function returns, the function 'json_object_get' shall be used.
143 static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info)
145 req.itf->success(req.closure, obj, info);
149 * Same as 'afb_req_success' but the 'info' is a formatting
150 * string followed by arguments.
152 * For conveniency, 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_f(struct afb_req req, struct json_object *obj, const char *info, ...)
160 va_start(args, info);
161 if (info == NULL || vasprintf(&message, info, args) < 0)
164 afb_req_success(req, obj, message);
169 * Sends a reply of kind failure to the request 'req'.
170 * The status of the reply is set to 'status' and an
171 * informationnal comment 'info' (can also be NULL) can be added.
173 * Note that calling afb_req_fail("success", info) is equivalent
174 * to call afb_req_success(NULL, info). Thus even if possible it
175 * is strongly recommanded to NEVER use "success" for status.
177 * For conveniency, the function calls 'json_object_put' for 'obj'.
178 * Thus, in the case where 'obj' should remain available after
179 * the function returns, the function 'json_object_get' shall be used.
181 static inline void afb_req_fail(struct afb_req req, const char *status, const char *info)
183 req.itf->fail(req.closure, status, info);
187 * Same as 'afb_req_fail' but the 'info' is a formatting
188 * string followed by arguments.
190 * For conveniency, 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_f(struct afb_req req, const char *status, const char *info, ...)
198 va_start(args, info);
199 if (info == NULL || vasprintf(&message, info, args) < 0)
202 afb_req_fail(req, status, message);
207 * Gets the pointer stored by the plugin for the session of 'req'.
208 * When the plugin has not yet recorded a pointer, NULL is returned.
210 static inline void *afb_req_context_get(struct afb_req req)
212 return req.itf->context_get(req.closure);
216 * Stores for the plugin the pointer 'context' to the session of 'req'.
217 * The function 'free_context' will be called when the session is closed
218 * or if plugin stores an other pointer.
220 static inline void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*))
222 req.itf->context_set(req.closure, context, free_context);
226 * Gets the pointer stored by the plugin for the session of 'req'.
227 * If the stored pointer is NULL, indicating that no pointer was
228 * already stored, afb_req_context creates a new context by calling
229 * the function 'create_context' and stores it with the freeing function
232 static inline void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*))
234 void *result = afb_req_context_get(req);
235 if (result == NULL) {
236 result = create_context();
237 afb_req_context_set(req, result, free_context);
243 * Frees the pointer stored by the plugin for the session of 'req'
244 * and sets it to NULL.
246 * Shortcut for: afb_req_context_set(req, NULL, NULL)
248 static inline void afb_req_context_clear(struct afb_req req)
250 afb_req_context_set(req, NULL, NULL);
254 * Adds one to the count of references of 'req'.
255 * This function MUST be called by asynchronous implementations
256 * of verbs if no reply was sent before returning.
258 static inline void afb_req_addref(struct afb_req req)
260 req.itf->addref(req.closure);
264 * Substracts one to the count of references of 'req'.
265 * This function MUST be called by asynchronous implementations
266 * of verbs after sending the asynchronous reply.
268 static inline void afb_req_unref(struct afb_req req)
270 req.itf->unref(req.closure);
274 * Closes the session associated with 'req'
275 * and delete all associated contexts.
277 static inline void afb_req_session_close(struct afb_req req)
279 req.itf->session_close(req.closure);
283 * Sets the level of assurance of the session of 'req'
284 * to 'level'. The effect of this function is subject of
286 * Returns 1 on success or 0 if failed.
288 static inline int afb_req_session_set_LOA(struct afb_req req, unsigned level)
290 return req.itf->session_set_LOA(req.closure, level);
294 * Stores 'req' on heap for asynchrnous use.
295 * Returns a pointer to the stored 'req' or NULL on memory depletion.
296 * The count of reference to 'req' is incremented on success
297 * (see afb_req_addref).
299 static inline struct afb_req *afb_req_store(struct afb_req req)
301 struct afb_req *result = malloc(sizeof *result);
302 if (result != NULL) {
310 * Retrieves the afb_req stored at 'req' and frees the memory.
311 * Returns the stored request.
312 * The count of reference is UNCHANGED, thus, normally, the
313 * function 'afb_req_unref' should be called on the result
314 * after that the asynchronous reply if sent.
316 static inline struct afb_req afb_req_unstore(struct afb_req *req)
318 struct afb_req result = *req;
324 * Establishes for the client link identified by 'req' a subscription
326 * Returns 0 in case of successful subscription or -1 in case of error.
328 static inline int afb_req_subscribe(struct afb_req req, struct afb_event event)
330 return req.itf->subscribe(req.closure, event);
334 * Revokes the subscription established to the 'event' for the client
335 * link identified by 'req'.
336 * Returns 0 in case of successful subscription or -1 in case of error.
338 static inline int afb_req_unsubscribe(struct afb_req req, struct afb_event event)
340 return req.itf->unsubscribe(req.closure, event);
347 static inline const char *afb_req_raw(struct afb_req req, size_t *size)
349 return req.itf->raw(req.closure, size);
353 static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size)
355 req.itf->send(req.closure, buffer, size);