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 /* avoid inclusion of <json-c/json.h> */
32 * Describes an argument (or parameter) of a request
35 const char *name; /* name of the argument or NULL if invalid */
36 const char *value; /* string representation of the value of the argument */
37 /* original filename of the argument if path != NULL */
38 const char *path; /* if not NULL, path of the received file for the argument */
39 /* when the request is finalized this file is removed */
43 * Interface for handling requests.
44 * It records the functions to be called for the request.
45 * Don't use this structure directly.
46 * Use the helper functions documented below.
49 /* CAUTION: respect the order, add at the end */
51 struct json_object *(*json)(void *closure);
52 struct afb_arg (*get)(void *closure, const char *name);
54 void (*success)(void *closure, struct json_object *obj, const char *info);
55 void (*fail)(void *closure, const char *status, const char *info);
57 const char *(*raw)(void *closure, size_t *size);
58 void (*send)(void *closure, const char *buffer, size_t size);
60 void *(*context_get)(void *closure);
61 void (*context_set)(void *closure, void *value, void (*free_value)(void*));
63 void (*addref)(void *closure);
64 void (*unref)(void *closure);
66 void (*session_close)(void *closure);
67 int (*session_set_LOA)(void *closure, unsigned level);
71 * Describes the request by plugins from afb-daemon
74 const struct afb_req_itf *itf; /* the interface to use */
75 void *closure; /* the closure argument for functions of 'itf' */
79 * Gets from the request 'req' the argument of 'name'.
80 * Returns a PLAIN structure of type 'struct afb_arg'.
81 * When the argument of 'name' is not found, all fields of result are set to NULL.
82 * When the argument of 'name' is found, the fields are filled,
83 * in particular, the field 'result.name' is set to 'name'.
85 * There is a special name value: the empty string.
86 * The argument of name "" is defined only if the request was made using
87 * an HTTP POST of Content-Type "application/json". In that case, the
88 * argument of name "" receives the value of the body of the HTTP request.
90 static inline struct afb_arg afb_req_get(struct afb_req req, const char *name)
92 return req.itf->get(req.closure, name);
96 * Gets from the request 'req' the string value of the argument of 'name'.
97 * Returns NULL if when there is no argument of 'name'.
98 * Returns the value of the argument of 'name' otherwise.
100 * Shortcut for: afb_req_get(req, name).value
102 static inline const char *afb_req_value(struct afb_req req, const char *name)
104 return afb_req_get(req, name).value;
108 * Gets from the request 'req' the path for file attached to the argument of 'name'.
109 * Returns NULL if when there is no argument of 'name' or when there is no file.
110 * Returns the path of the argument of 'name' otherwise.
112 * Shortcut for: afb_req_get(req, name).path
114 static inline const char *afb_req_path(struct afb_req req, const char *name)
116 return afb_req_get(req, name).path;
120 * Gets from the request 'req' the json object hashing the arguments.
121 * The returned object must not be released using 'json_object_put'.
123 static inline struct json_object *afb_req_json(struct afb_req req)
125 return req.itf->json(req.closure);
129 * Sends a reply of kind success to the request 'req'.
130 * The status of the reply is automatically set to "success".
131 * Its send the object 'obj' (can be NULL) with an
132 * informationnal comment 'info (can also be NULL).
134 * For conveniency, the function calls 'json_object_put' for 'obj'.
135 * Thus, in the case where 'obj' should remain available after
136 * the function returns, the function 'json_object_get' shall be used.
138 static inline void afb_req_success(struct afb_req req, struct json_object *obj, const char *info)
140 req.itf->success(req.closure, obj, info);
144 * Same as 'afb_req_success' but the 'info' is a formatting
145 * string followed by arguments.
147 * For conveniency, the function calls 'json_object_put' for 'obj'.
148 * Thus, in the case where 'obj' should remain available after
149 * the function returns, the function 'json_object_get' shall be used.
151 static inline void afb_req_success_f(struct afb_req req, struct json_object *obj, const char *info, ...)
155 va_start(args, info);
156 if (info == NULL || vasprintf(&message, info, args) < 0)
159 afb_req_success(req, obj, message);
164 * Sends a reply of kind failure to the request 'req'.
165 * The status of the reply is set to 'status' and an
166 * informationnal comment 'info' (can also be NULL) can be added.
168 * Note that calling afb_req_fail("success", info) is equivalent
169 * to call afb_req_success(NULL, info). Thus even if possible it
170 * is strongly recommanded to NEVER use "success" for status.
172 * For conveniency, the function calls 'json_object_put' for 'obj'.
173 * Thus, in the case where 'obj' should remain available after
174 * the function returns, the function 'json_object_get' shall be used.
176 static inline void afb_req_fail(struct afb_req req, const char *status, const char *info)
178 req.itf->fail(req.closure, status, info);
182 * Same as 'afb_req_fail' but the 'info' is a formatting
183 * string followed by arguments.
185 * For conveniency, the function calls 'json_object_put' for 'obj'.
186 * Thus, in the case where 'obj' should remain available after
187 * the function returns, the function 'json_object_get' shall be used.
189 static inline void afb_req_fail_f(struct afb_req req, const char *status, const char *info, ...)
193 va_start(args, info);
194 if (info == NULL || vasprintf(&message, info, args) < 0)
197 afb_req_fail(req, status, message);
202 * Gets the pointer stored by the plugin for the session of 'req'.
203 * When the plugin has not yet recorded a pointer, NULL is returned.
205 static inline void *afb_req_context_get(struct afb_req req)
207 return req.itf->context_get(req.closure);
211 * Stores for the plugin the pointer 'context' to the session of 'req'.
212 * The function 'free_context' will be called when the session is closed
213 * or if plugin stores an other pointer.
215 static inline void afb_req_context_set(struct afb_req req, void *context, void (*free_context)(void*))
217 req.itf->context_set(req.closure, context, free_context);
221 * Gets the pointer stored by the plugin for the session of 'req'.
222 * If the stored pointer is NULL, indicating that no pointer was
223 * already stored, afb_req_context creates a new context by calling
224 * the function 'create_context' and stores it with the freeing function
227 static inline void *afb_req_context(struct afb_req req, void *(*create_context)(), void (*free_context)(void*))
229 void *result = afb_req_context_get(req);
230 if (result == NULL) {
231 result = create_context();
232 afb_req_context_set(req, result, free_context);
238 * Frees the pointer stored by the plugin for the session of 'req'
239 * and sets it to NULL.
241 * Shortcut for: afb_req_context_set(req, NULL, NULL)
243 static inline void afb_req_context_clear(struct afb_req req)
245 afb_req_context_set(req, NULL, NULL);
249 * Adds one to the count of references of 'req'.
250 * This function MUST be called by asynchronous implementations
251 * of verbs if no reply was sent before returning.
253 static inline void afb_req_addref(struct afb_req req)
255 req.itf->addref(req.closure);
259 * Substracts one to the count of references of 'req'.
260 * This function MUST be called by asynchronous implementations
261 * of verbs after sending the asynchronous reply.
263 static inline void afb_req_unref(struct afb_req req)
265 req.itf->unref(req.closure);
269 * Closes the session associated with 'req'
270 * and delete all associated contexts.
272 static inline void afb_req_session_close(struct afb_req req)
274 req.itf->session_close(req.closure);
278 * Sets the level of assurance of the session of 'req'
279 * to 'level'. The effect of this function is subject of
281 * Returns 1 on success or 0 if failed.
283 static inline int afb_req_session_set_LOA(struct afb_req req, unsigned level)
285 return req.itf->session_set_LOA(req.closure, level);
289 * Stores 'req' on heap for asynchrnous use.
290 * Returns a pointer to the stored 'req' or NULL on memory depletion.
291 * The count of reference to 'req' is incremented on success
292 * (see afb_req_addref).
294 static inline struct afb_req *afb_req_store(struct afb_req req)
296 struct afb_req *result = malloc(sizeof *result);
297 if (result != NULL) {
305 * Retrieves the afb_req stored at 'req' and frees the memory.
306 * Returns the stored request.
307 * The count of reference is UNCHANGED, thus, normally, the
308 * function 'afb_req_unref' should be called on the result
309 * after that the asynchronous reply if sent.
311 static inline struct afb_req afb_req_unstore(struct afb_req *req)
313 struct afb_req result = *req;
319 static inline const char *afb_req_raw(struct afb_req req, size_t *size)
321 return req.itf->raw(req.closure, size);
325 static inline void afb_req_send(struct afb_req req, const char *buffer, size_t size)
327 req.itf->send(req.closure, buffer, size);