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_pooled_object(
  65                 mem_ctx, struct tevent_req, 2,
  66                 sizeof(struct tevent_immediate) + data_size);
  67         if (req == NULL) {
  68                 return NULL;
  69         }
  70         ZERO_STRUCTP(req);
  71         req->internal.private_type      = type;
  72         req->internal.create_location   = location;
  73         req->internal.finish_location   = NULL;
  74         req->internal.state             = TEVENT_REQ_IN_PROGRESS;
  75         req->internal.trigger           = tevent_create_immediate(req);
  76         if (!req->internal.trigger) {
  77                 talloc_free(req);
  78                 return NULL;
  79         }
  80         req->internal.defer_callback_ev = NULL;
  81
  82         data = talloc_zero_size(req, data_size);
  83         if (data == NULL) {
  84                 talloc_free(req);
  85                 return NULL;
  86         }
  87         talloc_set_name_const(data, type);
  88
  89         req->data = data;
  90
  91         *ppdata = data;
  92         return req;
  93 }
  94
  95 void _tevent_req_notify_callback(struct tevent_req *req, const char *location)
  96 {
  97         req->internal.finish_location = location;
  98         if (req->internal.defer_callback_ev) {
  99                 (void)tevent_req_post(req, req->internal.defer_callback_ev);
 100                 req->internal.defer_callback_ev = NULL;
 101                 return;
 102         }
 103         if (req->async.fn != NULL) {
 104                 req->async.fn(req);
 105         }
 106 }
 107
 108 static void tevent_req_finish(struct tevent_req *req,
 109                               enum tevent_req_state state,
 110                               const char *location)
 111 {
 112         req->internal.state = state;
 113         _tevent_req_notify_callback(req, location);
 114 }
 115
 116 void _tevent_req_done(struct tevent_req *req,
 117                       const char *location)
 118 {
 119         tevent_req_finish(req, TEVENT_REQ_DONE, location);
 120 }
 121
 122 bool _tevent_req_error(struct tevent_req *req,
 123                        uint64_t error,
 124                        const char *location)
 125 {
 126         if (error == 0) {
 127                 return false;
 128         }
 129
 130         req->internal.error = error;
 131         tevent_req_finish(req, TEVENT_REQ_USER_ERROR, location);
 132         return true;
 133 }
 134
 135 void _tevent_req_oom(struct tevent_req *req, const char *location)
 136 {
 137         tevent_req_finish(req, TEVENT_REQ_NO_MEMORY, location);
 138 }
 139
 140 bool _tevent_req_nomem(const void *p,
 141                        struct tevent_req *req,
 142                        const char *location)
 143 {
 144         if (p != NULL) {
 145                 return false;
 146         }
 147         _tevent_req_oom(req, location);
 148         return true;
 149 }
 150
 151 /**
 152  * @internal
 153  *
 154  * @brief Immediate event callback.
 155  *
 156  * @param[in]  ev       The event context to use.
 157  *
 158  * @param[in]  im       The immediate event.
 159  *
 160  * @param[in]  priv     The async request to be finished.
 161  */
 162 static void tevent_req_trigger(struct tevent_context *ev,
 163                                struct tevent_immediate *im,
 164                                void *private_data)
 165 {
 166         struct tevent_req *req = talloc_get_type(private_data,
 167                                  struct tevent_req);
 168
 169         tevent_req_finish(req, req->internal.state,
 170                           req->internal.finish_location);
 171 }
 172
 173 struct tevent_req *tevent_req_post(struct tevent_req *req,
 174                                    struct tevent_context *ev)
 175 {
 176         tevent_schedule_immediate(req->internal.trigger,
 177                                   ev, tevent_req_trigger, req);
 178         return req;
 179 }
 180
 181 void tevent_req_defer_callback(struct tevent_req *req,
 182                                struct tevent_context *ev)
 183 {
 184         req->internal.defer_callback_ev = ev;
 185 }
 186
 187 bool tevent_req_is_in_progress(struct tevent_req *req)
 188 {
 189         if (req->internal.state == TEVENT_REQ_IN_PROGRESS) {
 190                 return true;
 191         }
 192
 193         return false;
 194 }
 195
 196 void tevent_req_received(struct tevent_req *req)
 197 {
 198         TALLOC_FREE(req->data);
 199         req->private_print = NULL;
 200
 201         TALLOC_FREE(req->internal.trigger);
 202         TALLOC_FREE(req->internal.timer);
 203
 204         req->internal.state = TEVENT_REQ_RECEIVED;
 205 }
 206
 207 bool tevent_req_poll(struct tevent_req *req,
 208                      struct tevent_context *ev)
 209 {
 210         while (tevent_req_is_in_progress(req)) {
 211                 int ret;
 212
 213                 ret = tevent_loop_once(ev);
 214                 if (ret != 0) {
 215                         return false;
 216                 }
 217         }
 218
 219         return true;
 220 }
 221
 222 bool tevent_req_is_error(struct tevent_req *req, enum tevent_req_state *state,
 223                         uint64_t *error)
 224 {
 225         if (req->internal.state == TEVENT_REQ_DONE) {
 226                 return false;
 227         }
 228         if (req->internal.state == TEVENT_REQ_USER_ERROR) {
 229                 *error = req->internal.error;
 230         }
 231         *state = req->internal.state;
 232         return true;
 233 }
 234
 235 static void tevent_req_timedout(struct tevent_context *ev,
 236                                struct tevent_timer *te,
 237                                struct timeval now,
 238                                void *private_data)
 239 {
 240         struct tevent_req *req = talloc_get_type(private_data,
 241                                  struct tevent_req);
 242
 243         TALLOC_FREE(req->internal.timer);
 244
 245         tevent_req_finish(req, TEVENT_REQ_TIMED_OUT, __FUNCTION__);
 246 }
 247
 248 bool tevent_req_set_endtime(struct tevent_req *req,
 249                             struct tevent_context *ev,
 250                             struct timeval endtime)
 251 {
 252         TALLOC_FREE(req->internal.timer);
 253
 254         req->internal.timer = tevent_add_timer(ev, req, endtime,
 255                                                tevent_req_timedout,
 256                                                req);
 257         if (tevent_req_nomem(req->internal.timer, req)) {
 258                 return false;
 259         }
 260
 261         return true;
 262 }
 263
 264 void tevent_req_set_callback(struct tevent_req *req, tevent_req_fn fn, void *pvt)
 265 {
 266         req->async.fn = fn;
 267         req->async.private_data = pvt;
 268 }
 269
 270 void *_tevent_req_callback_data(struct tevent_req *req)
 271 {
 272         return req->async.private_data;
 273 }
 274
 275 void *_tevent_req_data(struct tevent_req *req)
 276 {
 277         return req->data;
 278 }
 279
 280 void tevent_req_set_print_fn(struct tevent_req *req, tevent_req_print_fn fn)
 281 {
 282         req->private_print = fn;
 283 }
 284
 285 void tevent_req_set_cancel_fn(struct tevent_req *req, tevent_req_cancel_fn fn)
 286 {
 287         req->private_cancel = fn;
 288 }
 289
 290 bool _tevent_req_cancel(struct tevent_req *req, const char *location)
 291 {
 292         if (req->private_cancel == NULL) {
 293                 return false;
 294         }
 295
 296         return req->private_cancel(req);
 297 }