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