lib/tevent/tevent.h

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    generalised event loop handling
   5
   6    Copyright (C) Andrew Tridgell 2005
   7    Copyright (C) Stefan Metzmacher 2005-2009
   8    Copyright (C) Volker Lendecke 2008
   9
  10      ** NOTE! The following LGPL license applies to the tevent
  11      ** library. This does NOT imply that all of Samba is released
  12      ** under the LGPL
  13
  14    This library is free software; you can redistribute it and/or
  15    modify it under the terms of the GNU Lesser General Public
  16    License as published by the Free Software Foundation; either
  17    version 3 of the License, or (at your option) any later version.
  18
  19    This library is distributed in the hope that it will be useful,
  20    but WITHOUT ANY WARRANTY; without even the implied warranty of
  21    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22    Lesser General Public License for more details.
  23
  24    You should have received a copy of the GNU Lesser General Public
  25    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  26 */
  27
  28 #ifndef __TEVENT_H__
  29 #define __TEVENT_H__
  30
  31 #include <stdint.h>
  32 #include <talloc.h>
  33 #include <sys/time.h>
  34 #include <stdbool.h>
  35
  36 struct tevent_context;
  37 struct tevent_ops;
  38 struct tevent_fd;
  39 struct tevent_timer;
  40 struct tevent_signal;
  41
  42 /* event handler types */
  43 typedef void (*tevent_fd_handler_t)(struct tevent_context *ev,
  44                                     struct tevent_fd *fde,
  45                                     uint16_t flags,
  46                                     void *private_data);
  47 typedef void (*tevent_fd_close_fn_t)(struct tevent_context *ev,
  48                                      struct tevent_fd *fde,
  49                                      int fd,
  50                                      void *private_data);
  51 typedef void (*tevent_timer_handler_t)(struct tevent_context *ev,
  52                                        struct tevent_timer *te,
  53                                        struct timeval current_time,
  54                                        void *private_data);
  55 typedef void (*tevent_signal_handler_t)(struct tevent_context *ev,
  56                                         struct tevent_signal *se,
  57                                         int signum,
  58                                         int count,
  59                                         void *siginfo,
  60                                         void *private_data);
  61
  62 struct tevent_context *tevent_context_init(TALLOC_CTX *mem_ctx);
  63 struct tevent_context *tevent_context_init_byname(TALLOC_CTX *mem_ctx, const char *name);
  64 const char **tevent_backend_list(TALLOC_CTX *mem_ctx);
  65 void tevent_set_default_backend(const char *backend);
  66
  67 struct tevent_fd *_tevent_add_fd(struct tevent_context *ev,
  68                                  TALLOC_CTX *mem_ctx,
  69                                  int fd,
  70                                  uint16_t flags,
  71                                  tevent_fd_handler_t handler,
  72                                  void *private_data,
  73                                  const char *handler_name,
  74                                  const char *location);
  75 #define tevent_add_fd(ev, mem_ctx, fd, flags, handler, private_data) \
  76         _tevent_add_fd(ev, mem_ctx, fd, flags, handler, private_data, \
  77                        #handler, __location__)
  78
  79 struct tevent_timer *_tevent_add_timer(struct tevent_context *ev,
  80                                        TALLOC_CTX *mem_ctx,
  81                                        struct timeval next_event,
  82                                        tevent_timer_handler_t handler,
  83                                        void *private_data,
  84                                        const char *handler_name,
  85                                        const char *location);
  86 #define tevent_add_timer(ev, mem_ctx, next_event, handler, private_data) \
  87         _tevent_add_timer(ev, mem_ctx, next_event, handler, private_data, \
  88                           #handler, __location__)
  89
  90 struct tevent_signal *_tevent_add_signal(struct tevent_context *ev,
  91                                          TALLOC_CTX *mem_ctx,
  92                                          int signum,
  93                                          int sa_flags,
  94                                          tevent_signal_handler_t handler,
  95                                          void *private_data,
  96                                          const char *handler_name,
  97                                          const char *location);
  98 #define tevent_add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data) \
  99         _tevent_add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data, \
 100                            #handler, __location__)
 101
 102 int tevent_loop_once(struct tevent_context *ev);
 103 int tevent_loop_wait(struct tevent_context *ev);
 104
 105 void tevent_fd_set_close_fn(struct tevent_fd *fde,
 106                             tevent_fd_close_fn_t close_fn);
 107 void tevent_fd_set_auto_close(struct tevent_fd *fde);
 108 uint16_t tevent_fd_get_flags(struct tevent_fd *fde);
 109 void tevent_fd_set_flags(struct tevent_fd *fde, uint16_t flags);
 110
 111 /* bits for file descriptor event flags */
 112 #define TEVENT_FD_READ 1
 113 #define TEVENT_FD_WRITE 2
 114
 115 #define TEVENT_FD_WRITEABLE(fde) \
 116         tevent_fd_set_flags(fde, tevent_fd_get_flags(fde) | TEVENT_FD_WRITE)
 117 #define TEVENT_FD_READABLE(fde) \
 118         tevent_fd_set_flags(fde, tevent_fd_get_flags(fde) | TEVENT_FD_READ)
 119
 120 #define TEVENT_FD_NOT_WRITEABLE(fde) \
 121         tevent_fd_set_flags(fde, tevent_fd_get_flags(fde) & ~TEVENT_FD_WRITE)
 122 #define TEVENT_FD_NOT_READABLE(fde) \
 123         tevent_fd_set_flags(fde, tevent_fd_get_flags(fde) & ~TEVENT_FD_READ)
 124
 125 /* DEBUG */
 126 enum tevent_debug_level {
 127         TEVENT_DEBUG_FATAL,
 128         TEVENT_DEBUG_ERROR,
 129         TEVENT_DEBUG_WARNING,
 130         TEVENT_DEBUG_TRACE
 131 };
 132
 133 int tevent_set_debug(struct tevent_context *ev,
 134                      void (*debug)(void *context,
 135                                    enum tevent_debug_level level,
 136                                    const char *fmt,
 137                                    va_list ap) PRINTF_ATTRIBUTE(3,0),
 138                      void *context);
 139 int tevent_set_debug_stderr(struct tevent_context *ev);
 140
 141 /**
 142  * An async request moves between the following 4 states:
 143  */
 144 enum tevent_req_state {
 145         /**
 146          * we are creating the request
 147          */
 148         TEVENT_REQ_INIT,
 149         /**
 150          * we are waiting the request to complete
 151          */
 152         TEVENT_REQ_IN_PROGRESS,
 153         /**
 154          * the request is finished
 155          */
 156         TEVENT_REQ_DONE,
 157         /**
 158          * A user error has occured
 159          */
 160         TEVENT_REQ_USER_ERROR,
 161         /**
 162          * Request timed out
 163          */
 164         TEVENT_REQ_TIMED_OUT,
 165         /**
 166          * No memory in between
 167          */
 168         TEVENT_REQ_NO_MEMORY,
 169         /**
 170          * the request is already received by the caller
 171          */
 172         TEVENT_REQ_RECEIVED
 173 };
 174
 175 /**
 176  * @brief An async request
 177  *
 178  * This represents an async request being processed by callbacks via an event
 179  * context. A user can issue for example a write request to a socket, giving
 180  * an implementation function the fd, the buffer and the number of bytes to
 181  * transfer. The function issuing the request will immediately return without
 182  * blocking most likely without having sent anything. The API user then fills
 183  * in req->async.fn and req->async.private_data, functions that are called
 184  * when the request is finished.
 185  *
 186  * It is up to the user of the async request to talloc_free it after it has
 187  * finished. This can happen while the completion function is called.
 188  */
 189
 190 struct tevent_req;
 191
 192 typedef void (*tevent_req_fn)(struct tevent_req *);
 193
 194 void tevent_req_set_callback(struct tevent_req *req, tevent_req_fn fn, void *pvt);
 195 void *_tevent_req_callback_data(struct tevent_req *req);
 196 void *_tevent_req_data(struct tevent_req *req);
 197
 198 #define tevent_req_callback_data(_req, _type) \
 199         talloc_get_type_abort(_tevent_req_callback_data(_req), _type)
 200 #define tevent_req_data(_req, _type) \
 201         talloc_get_type_abort(_tevent_req_data(_req), _type)
 202
 203 typedef char *(*tevent_req_print_fn)(struct tevent_req *, TALLOC_CTX *);
 204
 205 void tevent_req_set_print_fn(struct tevent_req *req, tevent_req_print_fn fn);
 206
 207 char *tevent_req_default_print(struct tevent_req *req, TALLOC_CTX *mem_ctx);
 208
 209 char *tevent_req_print(TALLOC_CTX *mem_ctx, struct tevent_req *req);
 210
 211 struct tevent_req *_tevent_req_create(TALLOC_CTX *mem_ctx,
 212                                       void *pstate,
 213                                       size_t state_size,
 214                                       const char *type,
 215                                       const char *location);
 216
 217 #define tevent_req_create(_mem_ctx, _pstate, _type) \
 218         _tevent_req_create((_mem_ctx), (_pstate), sizeof(_type), \
 219                            #_type, __location__)
 220
 221 bool tevent_req_set_endtime(struct tevent_req *req,
 222                             struct tevent_context *ev,
 223                             struct timeval endtime);
 224
 225 void tevent_req_done(struct tevent_req *req);
 226
 227 bool tevent_req_error(struct tevent_req *req,
 228                       uint64_t error);
 229
 230 bool tevent_req_nomem(const void *p,
 231                       struct tevent_req *req);
 232
 233 struct tevent_req *tevent_req_post(struct tevent_req *req,
 234                                    struct tevent_context *ev);
 235
 236 bool tevent_req_is_in_progress(struct tevent_req *req);
 237
 238 bool tevent_req_poll(struct tevent_req *req,
 239                      struct tevent_context *ev);
 240
 241 bool tevent_req_is_error(struct tevent_req *req,
 242                          enum tevent_req_state *state,
 243                          uint64_t *error);
 244
 245 void tevent_req_received(struct tevent_req *req);
 246
 247 struct tevent_req *tevent_wakeup_send(TALLOC_CTX *mem_ctx,
 248                                       struct tevent_context *ev,
 249                                       struct timeval wakeup_time);
 250 bool tevent_wakeup_recv(struct tevent_req *req);
 251
 252 int tevent_timeval_compare(const struct timeval *tv1,
 253                            const struct timeval *tv2);
 254
 255 struct timeval tevent_timeval_zero(void);
 256
 257 struct timeval tevent_timeval_current(void);
 258
 259 struct timeval tevent_timeval_set(uint32_t secs, uint32_t usecs);
 260
 261 struct timeval tevent_timeval_until(const struct timeval *tv1,
 262                                     const struct timeval *tv2);
 263
 264 bool tevent_timeval_is_zero(const struct timeval *tv);
 265
 266 struct timeval tevent_timeval_add(const struct timeval *tv, uint32_t secs,
 267                                   uint32_t usecs);
 268
 269 struct timeval tevent_timeval_current_ofs(uint32_t secs, uint32_t usecs);
 270
 271 struct tevent_queue;
 272
 273 struct tevent_queue *_tevent_queue_create(TALLOC_CTX *mem_ctx,
 274                                           const char *name,
 275                                           const char *location);
 276
 277 #define tevent_queue_create(_mem_ctx, _name) \
 278         _tevent_queue_create((_mem_ctx), (_name), __location__)
 279
 280 typedef void (*tevent_queue_trigger_fn_t)(struct tevent_req *req,
 281                                           void *private_data);
 282 bool tevent_queue_add(struct tevent_queue *queue,
 283                       struct tevent_context *ev,
 284                       struct tevent_req *req,
 285                       tevent_queue_trigger_fn_t trigger,
 286                       void *private_data);
 287 bool tevent_queue_start(struct tevent_queue *queue,
 288                         struct tevent_context *ev);
 289 void tevent_queue_stop(struct tevent_queue *queue);
 290
 291 size_t tevent_queue_length(struct tevent_queue *queue);
 292
 293 #ifdef TEVENT_COMPAT_DEFINES
 294
 295 #define event_context   tevent_context
 296 #define event_ops       tevent_ops
 297 #define fd_event        tevent_fd
 298 #define timed_event     tevent_timer
 299 #define signal_event    tevent_signal
 300
 301 #define event_fd_handler_t      tevent_fd_handler_t
 302 #define event_timed_handler_t   tevent_timer_handler_t
 303 #define event_signal_handler_t  tevent_signal_handler_t
 304
 305 #define event_context_init(mem_ctx) \
 306         tevent_context_init(mem_ctx)
 307
 308 #define event_context_init_byname(mem_ctx, name) \
 309         tevent_context_init_byname(mem_ctx, name)
 310
 311 #define event_backend_list(mem_ctx) \
 312         tevent_backend_list(mem_ctx)
 313
 314 #define event_set_default_backend(backend) \
 315         tevent_set_default_backend(backend)
 316
 317 #define event_add_fd(ev, mem_ctx, fd, flags, handler, private_data) \
 318         tevent_add_fd(ev, mem_ctx, fd, flags, handler, private_data)
 319
 320 #define event_add_timed(ev, mem_ctx, next_event, handler, private_data) \
 321         tevent_add_timer(ev, mem_ctx, next_event, handler, private_data)
 322
 323 #define event_add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data) \
 324         tevent_add_signal(ev, mem_ctx, signum, sa_flags, handler, private_data)
 325
 326 #define event_loop_once(ev) \
 327         tevent_loop_once(ev)
 328
 329 #define event_loop_wait(ev) \
 330         tevent_loop_wait(ev)
 331
 332 #define event_get_fd_flags(fde) \
 333         tevent_fd_get_flags(fde)
 334
 335 #define event_set_fd_flags(fde, flags) \
 336         tevent_fd_set_flags(fde, flags)
 337
 338 #define EVENT_FD_READ           TEVENT_FD_READ
 339 #define EVENT_FD_WRITE          TEVENT_FD_WRITE
 340
 341 #define EVENT_FD_WRITEABLE(fde) \
 342         TEVENT_FD_WRITEABLE(fde)
 343
 344 #define EVENT_FD_READABLE(fde) \
 345         TEVENT_FD_READABLE(fde)
 346
 347 #define EVENT_FD_NOT_WRITEABLE(fde) \
 348         TEVENT_FD_NOT_WRITEABLE(fde)
 349
 350 #define EVENT_FD_NOT_READABLE(fde) \
 351         TEVENT_FD_NOT_READABLE(fde)
 352
 353 #define ev_debug_level          tevent_debug_level
 354
 355 #define EV_DEBUG_FATAL          TEVENT_DEBUG_FATAL
 356 #define EV_DEBUG_ERROR          TEVENT_DEBUG_ERROR
 357 #define EV_DEBUG_WARNING        TEVENT_DEBUG_WARNING
 358 #define EV_DEBUG_TRACE          TEVENT_DEBUG_TRACE
 359
 360 #define ev_set_debug(ev, debug, context) \
 361         tevent_set_debug(ev, debug, context)
 362
 363 #define ev_set_debug_stderr(_ev) tevent_set_debug_stderr(ev)
 364
 365 #endif /* TEVENT_COMPAT_DEFINES */
 366
 367 #endif /* __TEVENT_H__ */