lib/tevent/tevent_req.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Infrastructure for async requests
   4    Copyright (C) Volker Lendecke 2008
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7      ** NOTE! The following LGPL license applies to the tevent
   8      ** library. This does NOT imply that all of Samba is released
   9      ** under the LGPL
  10
  11    This library is free software; you can redistribute it and/or
  12    modify it under the terms of the GNU Lesser General Public
  13    License as published by the Free Software Foundation; either
  14    version 3 of the License, or (at your option) any later version.
  15
  16    This library is distributed in the hope that it will be useful,
  17    but WITHOUT ANY WARRANTY; without even the implied warranty of
  18    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19    Lesser General Public License for more details.
  20
  21    You should have received a copy of the GNU Lesser General Public
  22    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "replace.h"
  26 #include "tevent.h"
  27 #include "tevent_internal.h"
  28 #include "tevent_util.h"
  29
  30 char *tevent_req_default_print(struct tevent_req *req, TALLOC_CTX *mem_ctx)
  31 {
  32         return talloc_asprintf(mem_ctx,
  33                                "tevent_req[%p/%s]: state[%d] error[%lld (0x%llX)] "
  34                                " state[%s (%p)] timer[%p]",
  35                                req, req->internal.create_location,
  36                                req->internal.state,
  37                                (unsigned long long)req->internal.error,
  38                                (unsigned long long)req->internal.error,
  39                                talloc_get_name(req->data),
  40                                req->data,
  41                                req->internal.timer
  42                                );
  43 }
  44
  45 char *tevent_req_print(TALLOC_CTX *mem_ctx, struct tevent_req *req)
  46 {
  47         if (!req->private_print) {
  48                 return tevent_req_default_print(req, mem_ctx);
  49         }
  50
  51         return req->private_print(req, mem_ctx);
  52 }
  53
  54 struct tevent_req *_tevent_req_create(TALLOC_CTX *mem_ctx,
  55                                     void *pdata,
  56                                     size_t data_size,
  57                                     const char *type,
  58                                     const char *location)
  59 {
  60         struct tevent_req *req;
  61         void **ppdata = (void **)pdata;
  62         void *data;
  63
  64         req = talloc_zero(mem_ctx, struct tevent_req);
  65         if (req == NULL) {
  66                 return NULL;
  67         }
  68         req->internal.private_type      = type;
  69         req->internal.create_location   = location;
  70         req->internal.finish_location   = NULL;
  71         req->internal.state             = TEVENT_REQ_IN_PROGRESS;
  72         req->internal.trigger           = tevent_create_immediate(req);
  73         if (!req->internal.trigger) {
  74                 talloc_free(req);
  75                 return NULL;
  76         }
  77         req->internal.defer_callback_ev = NULL;
  78
  79         data = talloc_zero_size(req, data_size);
  80         if (data == NULL) {
  81                 talloc_free(req);
  82                 return NULL;
  83         }
  84         talloc_set_name_const(data, type);
  85
  86         req->data = data;
  87
  88         *ppdata = data;
  89         return req;
  90 }
  91
  92 void _tevent_req_notify_callback(struct tevent_req *req, const char *location)
  93 {
  94         req->internal.finish_location = location;
  95         if (req->internal.defer_callback_ev) {
  96                 (void)tevent_req_post(req, req->internal.defer_callback_ev);
  97                 req->internal.defer_callback_ev = NULL;
  98                 return;
  99         }
 100         if (req->async.fn != NULL) {
 101                 req->async.fn(req);
 102         }
 103 }
 104
 105 static void tevent_req_finish(struct tevent_req *req,
 106                               enum tevent_req_state state,
 107                               const char *location)
 108 {
 109         req->internal.state = state;
 110         _tevent_req_notify_callback(req, location);
 111 }
 112
 113 void _tevent_req_done(struct tevent_req *req,
 114                       const char *location)
 115 {
 116         tevent_req_finish(req, TEVENT_REQ_DONE, location);
 117 }
 118
 119 bool _tevent_req_error(struct tevent_req *req,
 120                        uint64_t error,
 121                        const char *location)
 122 {
 123         if (error == 0) {
 124                 return false;
 125         }
 126
 127         req->internal.error = error;
 128         tevent_req_finish(req, TEVENT_REQ_USER_ERROR, location);
 129         return true;
 130 }
 131
 132 void _tevent_req_oom(struct tevent_req *req, const char *location)
 133 {
 134         tevent_req_finish(req, TEVENT_REQ_NO_MEMORY, location);
 135 }
 136
 137 bool _tevent_req_nomem(const void *p,
 138                        struct tevent_req *req,
 139                        const char *location)
 140 {
 141         if (p != NULL) {
 142                 return false;
 143         }
 144         _tevent_req_oom(req, location);
 145         return true;
 146 }
 147
 148 /**
 149  * @internal
 150  *
 151  * @brief Immediate event callback.
 152  *
 153  * @param[in]  ev       The event context to use.
 154  *
 155  * @param[in]  im       The immediate event.
 156  *
 157  * @param[in]  priv     The async request to be finished.
 158  */
 159 static void tevent_req_trigger(struct tevent_context *ev,
 160                                struct tevent_immediate *im,
 161                                void *private_data)
 162 {
 163         struct tevent_req *req = talloc_get_type(private_data,
 164                                  struct tevent_req);
 165
 166         tevent_req_finish(req, req->internal.state,
 167                           req->internal.finish_location);
 168 }
 169
 170 struct tevent_req *tevent_req_post(struct tevent_req *req,
 171                                    struct tevent_context *ev)
 172 {
 173         tevent_schedule_immediate(req->internal.trigger,
 174                                   ev, tevent_req_trigger, req);
 175         return req;
 176 }
 177
 178 void tevent_req_defer_callback(struct tevent_req *req,
 179                                struct tevent_context *ev)
 180 {
 181         req->internal.defer_callback_ev = ev;
 182 }
 183
 184 bool tevent_req_is_in_progress(struct tevent_req *req)
 185 {
 186         if (req->internal.state == TEVENT_REQ_IN_PROGRESS) {
 187                 return true;
 188         }
 189
 190         return false;
 191 }
 192
 193 void tevent_req_received(struct tevent_req *req)
 194 {
 195         TALLOC_FREE(req->data);
 196         req->private_print = NULL;
 197
 198         TALLOC_FREE(req->internal.trigger);
 199         TALLOC_FREE(req->internal.timer);
 200
 201         req->internal.state = TEVENT_REQ_RECEIVED;
 202 }
 203
 204 bool tevent_req_poll(struct tevent_req *req,
 205                      struct tevent_context *ev)
 206 {
 207         while (tevent_req_is_in_progress(req)) {
 208                 int ret;
 209
 210                 ret = tevent_loop_once(ev);
 211                 if (ret != 0) {
 212                         return false;
 213                 }
 214         }
 215
 216         return true;
 217 }
 218
 219 bool tevent_req_is_error(struct tevent_req *req, enum tevent_req_state *state,
 220                         uint64_t *error)
 221 {
 222         if (req->internal.state == TEVENT_REQ_DONE) {
 223                 return false;
 224         }
 225         if (req->internal.state == TEVENT_REQ_USER_ERROR) {
 226                 *error = req->internal.error;
 227         }
 228         *state = req->internal.state;
 229         return true;
 230 }
 231
 232 static void tevent_req_timedout(struct tevent_context *ev,
 233                                struct tevent_timer *te,
 234                                struct timeval now,
 235                                void *private_data)
 236 {
 237         struct tevent_req *req = talloc_get_type(private_data,
 238                                  struct tevent_req);
 239
 240         TALLOC_FREE(req->internal.timer);
 241
 242         tevent_req_finish(req, TEVENT_REQ_TIMED_OUT, __FUNCTION__);
 243 }
 244
 245 bool tevent_req_set_endtime(struct tevent_req *req,
 246                             struct tevent_context *ev,
 247                             struct timeval endtime)
 248 {
 249         TALLOC_FREE(req->internal.timer);
 250
 251         req->internal.timer = tevent_add_timer(ev, req, endtime,
 252                                                tevent_req_timedout,
 253                                                req);
 254         if (tevent_req_nomem(req->internal.timer, req)) {
 255                 return false;
 256         }
 257
 258         return true;
 259 }
 260
 261 void tevent_req_set_callback(struct tevent_req *req, tevent_req_fn fn, void *pvt)
 262 {
 263         req->async.fn = fn;
 264         req->async.private_data = pvt;
 265 }
 266
 267 void *_tevent_req_callback_data(struct tevent_req *req)
 268 {
 269         return req->async.private_data;
 270 }
 271
 272 void *_tevent_req_data(struct tevent_req *req)
 273 {
 274         return req->data;
 275 }
 276
 277 void tevent_req_set_print_fn(struct tevent_req *req, tevent_req_print_fn fn)
 278 {
 279         req->private_print = fn;
 280 }
 281
 282 void tevent_req_set_cancel_fn(struct tevent_req *req, tevent_req_cancel_fn fn)
 283 {
 284         req->private_cancel = fn;
 285 }
 286
 287 bool _tevent_req_cancel(struct tevent_req *req, const char *location)
 288 {
 289         if (req->private_cancel == NULL) {
 290                 return false;
 291         }
 292
 293         return req->private_cancel(req);
 294 }