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Diffstat (limited to 'src/lib/util/op.c')
-rw-r--r-- | src/lib/util/op.c | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/src/lib/util/op.c b/src/lib/util/op.c new file mode 100644 index 000000000..a8fc3de4a --- /dev/null +++ b/src/lib/util/op.c | |||
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1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2016 GNUnet e.V. | ||
4 | |||
5 | GNUnet is free software: you can redistribute it and/or modify it | ||
6 | under the terms of the GNU Affero General Public License as published | ||
7 | by the Free Software Foundation, either version 3 of the License, | ||
8 | or (at your option) any later version. | ||
9 | |||
10 | GNUnet is distributed in the hope that it will be useful, but | ||
11 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
13 | Affero General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU Affero General Public License | ||
16 | along with this program. If not, see <http://www.gnu.org/licenses/>. | ||
17 | |||
18 | SPDX-License-Identifier: AGPL3.0-or-later | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file | ||
23 | * Asynchronous operations; register callbacks for operations and call them when a response arrives. | ||
24 | * | ||
25 | * @author Gabor X Toth | ||
26 | */ | ||
27 | |||
28 | #include "platform.h" | ||
29 | #include <inttypes.h> | ||
30 | |||
31 | |||
32 | #include "gnunet_util_lib.h" | ||
33 | |||
34 | #define LOG(kind, ...) GNUNET_log_from (kind, "util-op", __VA_ARGS__) | ||
35 | |||
36 | struct OperationListItem | ||
37 | { | ||
38 | struct OperationListItem *prev; | ||
39 | struct OperationListItem *next; | ||
40 | |||
41 | /** | ||
42 | * Operation ID. | ||
43 | */ | ||
44 | uint64_t op_id; | ||
45 | |||
46 | /** | ||
47 | * Continuation to invoke with the result of an operation. | ||
48 | */ | ||
49 | GNUNET_ResultCallback result_cb; | ||
50 | |||
51 | /** | ||
52 | * Closure for @a result_cb. | ||
53 | */ | ||
54 | void *cls; | ||
55 | |||
56 | /** | ||
57 | * User context. | ||
58 | */ | ||
59 | void *ctx; | ||
60 | }; | ||
61 | |||
62 | |||
63 | /** | ||
64 | * Operations handle. | ||
65 | */ | ||
66 | |||
67 | struct GNUNET_OP_Handle | ||
68 | { | ||
69 | /** | ||
70 | * First operation in the linked list. | ||
71 | */ | ||
72 | struct OperationListItem *op_head; | ||
73 | |||
74 | /** | ||
75 | * Last operation in the linked list. | ||
76 | */ | ||
77 | struct OperationListItem *op_tail; | ||
78 | |||
79 | /** | ||
80 | * Last operation ID used. | ||
81 | */ | ||
82 | uint64_t last_op_id; | ||
83 | }; | ||
84 | |||
85 | |||
86 | /** | ||
87 | * Create new operations handle. | ||
88 | */ | ||
89 | struct GNUNET_OP_Handle * | ||
90 | GNUNET_OP_create () | ||
91 | { | ||
92 | return GNUNET_new (struct GNUNET_OP_Handle); | ||
93 | } | ||
94 | |||
95 | |||
96 | /** | ||
97 | * Destroy operations handle. | ||
98 | */ | ||
99 | void | ||
100 | GNUNET_OP_destroy (struct GNUNET_OP_Handle *h) | ||
101 | { | ||
102 | GNUNET_free (h); | ||
103 | } | ||
104 | |||
105 | |||
106 | /** | ||
107 | * Get a unique operation ID to distinguish between asynchronous requests. | ||
108 | * | ||
109 | * @param h | ||
110 | * Operations handle. | ||
111 | * | ||
112 | * @return Operation ID to use. | ||
113 | */ | ||
114 | uint64_t | ||
115 | GNUNET_OP_get_next_id (struct GNUNET_OP_Handle *h) | ||
116 | { | ||
117 | return ++h->last_op_id; | ||
118 | } | ||
119 | |||
120 | |||
121 | /** | ||
122 | * Find operation by ID. | ||
123 | * | ||
124 | * @param h | ||
125 | * Operations handle. | ||
126 | * @param op_id | ||
127 | * Operation ID to look up. | ||
128 | * | ||
129 | * @return Operation, or NULL if not found. | ||
130 | */ | ||
131 | static struct OperationListItem * | ||
132 | op_find (struct GNUNET_OP_Handle *h, | ||
133 | uint64_t op_id) | ||
134 | { | ||
135 | struct OperationListItem *op; | ||
136 | |||
137 | for (op = h->op_head; NULL != op; op = op->next) | ||
138 | if (op->op_id == op_id) | ||
139 | return op; | ||
140 | return NULL; | ||
141 | } | ||
142 | |||
143 | |||
144 | /** | ||
145 | * Find operation by ID. | ||
146 | * | ||
147 | * @param h | ||
148 | * Operations handle. | ||
149 | * @param op_id | ||
150 | * Operation ID to look up. | ||
151 | * @param[out] result_cb | ||
152 | * If an operation was found, its result callback is returned here. | ||
153 | * @param[out] cls | ||
154 | * If an operation was found, its closure is returned here. | ||
155 | * @param[out] ctx | ||
156 | * If an operation was found, its user context is returned here. | ||
157 | * | ||
158 | * @return #GNUNET_YES if an operation was found, | ||
159 | * #GNUNET_NO if not found. | ||
160 | */ | ||
161 | int | ||
162 | GNUNET_OP_get (struct GNUNET_OP_Handle *h, | ||
163 | uint64_t op_id, | ||
164 | GNUNET_ResultCallback *result_cb, | ||
165 | void **cls, | ||
166 | void **ctx) | ||
167 | { | ||
168 | struct OperationListItem *op = op_find (h, op_id); | ||
169 | |||
170 | if (NULL != op) | ||
171 | { | ||
172 | if (NULL != result_cb) | ||
173 | *result_cb = op->result_cb; | ||
174 | if (NULL != cls) | ||
175 | *cls = op->cls; | ||
176 | if (NULL != ctx) | ||
177 | *ctx = op->ctx; | ||
178 | return GNUNET_YES; | ||
179 | } | ||
180 | return GNUNET_NO; | ||
181 | } | ||
182 | |||
183 | |||
184 | /** | ||
185 | * Add a new operation. | ||
186 | * | ||
187 | * @param h | ||
188 | * Operations handle. | ||
189 | * @param result_cb | ||
190 | * Function to call with the result of the operation. | ||
191 | * @param cls | ||
192 | * Closure for @a result_cb. | ||
193 | * @param ctx | ||
194 | * User context. | ||
195 | * | ||
196 | * @return ID of the new operation. | ||
197 | */ | ||
198 | uint64_t | ||
199 | GNUNET_OP_add (struct GNUNET_OP_Handle *h, | ||
200 | GNUNET_ResultCallback result_cb, | ||
201 | void *cls, | ||
202 | void *ctx) | ||
203 | { | ||
204 | struct OperationListItem *op; | ||
205 | |||
206 | op = GNUNET_new (struct OperationListItem); | ||
207 | op->op_id = GNUNET_OP_get_next_id (h); | ||
208 | op->result_cb = result_cb; | ||
209 | op->cls = cls; | ||
210 | op->ctx = ctx; | ||
211 | GNUNET_CONTAINER_DLL_insert_tail (h->op_head, | ||
212 | h->op_tail, | ||
213 | op); | ||
214 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
215 | "%p Added operation #%" PRIu64 "\n", | ||
216 | h, op->op_id); | ||
217 | return op->op_id; | ||
218 | } | ||
219 | |||
220 | |||
221 | /** | ||
222 | * Remove an operation, and call its result callback (unless it was cancelled). | ||
223 | * | ||
224 | * | ||
225 | * @param h | ||
226 | * Operations handle. | ||
227 | * @param op_id | ||
228 | * Operation ID. | ||
229 | * @param result_code | ||
230 | * Result of the operation. | ||
231 | * @param data | ||
232 | * Data result of the operation. | ||
233 | * @param data_size | ||
234 | * Size of @a data. | ||
235 | * @param[out] ctx | ||
236 | * User context. | ||
237 | * @param cancel | ||
238 | * Is the operation cancelled? | ||
239 | * #GNUNET_NO Not cancelled, result callback is called. | ||
240 | * #GNUNET_YES Cancelled, result callback is not called. | ||
241 | * | ||
242 | * @return #GNUNET_YES if the operation was found and removed, | ||
243 | * #GNUNET_NO if the operation was not found. | ||
244 | */ | ||
245 | static int | ||
246 | op_result (struct GNUNET_OP_Handle *h, | ||
247 | uint64_t op_id, | ||
248 | int64_t result_code, | ||
249 | const void *data, | ||
250 | uint16_t data_size, | ||
251 | void **ctx, | ||
252 | uint8_t cancel) | ||
253 | { | ||
254 | if (0 == op_id) | ||
255 | return GNUNET_NO; | ||
256 | |||
257 | struct OperationListItem *op = op_find (h, op_id); | ||
258 | if (NULL == op) | ||
259 | { | ||
260 | LOG (GNUNET_ERROR_TYPE_WARNING, | ||
261 | "Could not find operation #%" PRIu64 "\n", op_id); | ||
262 | return GNUNET_NO; | ||
263 | } | ||
264 | |||
265 | if (NULL != ctx) | ||
266 | *ctx = op->ctx; | ||
267 | |||
268 | GNUNET_CONTAINER_DLL_remove (h->op_head, | ||
269 | h->op_tail, | ||
270 | op); | ||
271 | |||
272 | if ((GNUNET_YES != cancel) && | ||
273 | (NULL != op->result_cb)) | ||
274 | op->result_cb (op->cls, | ||
275 | result_code, data, | ||
276 | data_size); | ||
277 | GNUNET_free (op); | ||
278 | return GNUNET_YES; | ||
279 | } | ||
280 | |||
281 | |||
282 | /** | ||
283 | * Call the result callback of an operation and remove it. | ||
284 | * | ||
285 | * @param h | ||
286 | * Operations handle. | ||
287 | * @param op_id | ||
288 | * Operation ID. | ||
289 | * @param result_code | ||
290 | * Result of the operation. | ||
291 | * @param data | ||
292 | * Data result of the operation. | ||
293 | * @param data_size | ||
294 | * Size of @a data. | ||
295 | * @param[out] ctx | ||
296 | * User context. | ||
297 | * | ||
298 | * @return #GNUNET_YES if the operation was found and removed, | ||
299 | * #GNUNET_NO if the operation was not found. | ||
300 | */ | ||
301 | int | ||
302 | GNUNET_OP_result (struct GNUNET_OP_Handle *h, | ||
303 | uint64_t op_id, | ||
304 | int64_t result_code, | ||
305 | const void *data, | ||
306 | uint16_t data_size, | ||
307 | void **ctx) | ||
308 | { | ||
309 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
310 | "%p Received result for operation #%" PRIu64 ": %" PRId64 " (size: %u)\n", | ||
311 | h, op_id, result_code, data_size); | ||
312 | return op_result (h, op_id, result_code, data, data_size, ctx, GNUNET_NO); | ||
313 | } | ||
314 | |||
315 | |||
316 | /** | ||
317 | * Remove / cancel an operation. | ||
318 | * | ||
319 | * @param h | ||
320 | * Operations handle. | ||
321 | * @param op_id | ||
322 | * Operation ID. | ||
323 | * | ||
324 | * @return #GNUNET_YES if the operation was found and removed, | ||
325 | * #GNUNET_NO if the operation was not found. | ||
326 | */ | ||
327 | int | ||
328 | GNUNET_OP_remove (struct GNUNET_OP_Handle *h, | ||
329 | uint64_t op_id) | ||
330 | { | ||
331 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
332 | "%p Cancelling operation #%" PRIu64 "\n", | ||
333 | h, op_id); | ||
334 | return op_result (h, op_id, 0, NULL, 0, NULL, GNUNET_YES); | ||
335 | } | ||