lib/tevent/tevent_internal.h

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    generalised event loop handling
   5
   6    INTERNAL STRUCTS. THERE ARE NO API GUARANTEES.
   7    External users should only ever have to include this header when
   8    implementing new tevent backends.
   9
  10    Copyright (C) Stefan Metzmacher 2005-2009
  11
  12      ** NOTE! The following LGPL license applies to the tevent
  13      ** library. This does NOT imply that all of Samba is released
  14      ** under the LGPL
  15
  16    This library is free software; you can redistribute it and/or
  17    modify it under the terms of the GNU Lesser General Public
  18    License as published by the Free Software Foundation; either
  19    version 3 of the License, or (at your option) any later version.
  20
  21    This library is distributed in the hope that it will be useful,
  22    but WITHOUT ANY WARRANTY; without even the implied warranty of
  23    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  24    Lesser General Public License for more details.
  25
  26    You should have received a copy of the GNU Lesser General Public
  27    License along with this library; if not, see <http://www.gnu.org/licenses/>.
  28 */
  29
  30 struct tevent_req {
  31         /**
  32          * @brief What to do on completion
  33          *
  34          * This is used for the user of an async request, fn is called when
  35          * the request completes, either successfully or with an error.
  36          */
  37         struct {
  38                 /**
  39                  * @brief Completion function
  40                  * Completion function, to be filled by the API user
  41                  */
  42                 tevent_req_fn fn;
  43                 /**
  44                  * @brief Private data for the completion function
  45                  */
  46                 void *private_data;
  47         } async;
  48
  49         /**
  50          * @brief Private state pointer for the actual implementation
  51          *
  52          * The implementation doing the work for the async request needs to
  53          * keep around current data like for example a fd event. The user of
  54          * an async request should not touch this.
  55          */
  56         void *data;
  57
  58         /**
  59          * @brief A function to overwrite the default print function
  60          *
  61          * The implementation doing the work may want to implement a
  62          * custom function to print the text representation of the async
  63          * request.
  64          */
  65         tevent_req_print_fn private_print;
  66
  67         /**
  68          * @brief A function to cancel the request
  69          *
  70          * The implementation might want to set a function
  71          * that is called when the tevent_req_cancel() function
  72          * was called.
  73          */
  74         tevent_req_cancel_fn private_cancel;
  75
  76         /**
  77          * @brief A function to cleanup the request
  78          *
  79          * The implementation might want to set a function
  80          * that is called before the tevent_req_done() and tevent_req_error()
  81          * trigger the callers callback function.
  82          */
  83         struct {
  84                 tevent_req_cleanup_fn fn;
  85                 enum tevent_req_state state;
  86         } private_cleanup;
  87
  88         /**
  89          * @brief Internal state of the request
  90          *
  91          * Callers should only access this via functions and never directly.
  92          */
  93         struct {
  94                 /**
  95                  * @brief The talloc type of the data pointer
  96                  *
  97                  * This is filled by the tevent_req_create() macro.
  98                  *
  99                  * This for debugging only.
 100                  */
 101                 const char *private_type;
 102
 103                 /**
 104                  * @brief The location where the request was created
 105                  *
 106                  * This uses the __location__ macro via the tevent_req_create()
 107                  * macro.
 108                  *
 109                  * This for debugging only.
 110                  */
 111                 const char *create_location;
 112
 113                 /**
 114                  * @brief The location where the request was finished
 115                  *
 116                  * This uses the __location__ macro via the tevent_req_done(),
 117                  * tevent_req_error() or tevent_req_nomem() macro.
 118                  *
 119                  * This for debugging only.
 120                  */
 121                 const char *finish_location;
 122
 123                 /**
 124                  * @brief The location where the request was canceled
 125                  *
 126                  * This uses the __location__ macro via the
 127                  * tevent_req_cancel() macro.
 128                  *
 129                  * This for debugging only.
 130                  */
 131                 const char *cancel_location;
 132
 133                 /**
 134                  * @brief The external state - will be queried by the caller
 135                  *
 136                  * While the async request is being processed, state will remain in
 137                  * TEVENT_REQ_IN_PROGRESS. A request is finished if
 138                  * req->state>=TEVENT_REQ_DONE.
 139                  */
 140                 enum tevent_req_state state;
 141
 142                 /**
 143                  * @brief status code when finished
 144                  *
 145                  * This status can be queried in the async completion function. It
 146                  * will be set to 0 when everything went fine.
 147                  */
 148                 uint64_t error;
 149
 150                 /**
 151                  * @brief the immediate event used by tevent_req_post
 152                  *
 153                  */
 154                 struct tevent_immediate *trigger;
 155
 156                 /**
 157                  * @brief An event context which will be used to
 158                  *        defer the _tevent_req_notify_callback().
 159                  */
 160                 struct tevent_context *defer_callback_ev;
 161
 162                 /**
 163                  * @brief the timer event if tevent_req_set_endtime was used
 164                  *
 165                  */
 166                 struct tevent_timer *timer;
 167
 168                 /**
 169                  * @brief The place where profiling data is kept
 170                  */
 171                 struct tevent_req_profile *profile;
 172         } internal;
 173 };
 174
 175 struct tevent_req_profile {
 176         struct tevent_req_profile *prev, *next;
 177         struct tevent_req_profile *parent;
 178         const char *req_name;
 179         pid_t pid;
 180         const char *start_location;
 181         struct timeval start_time;
 182         const char *stop_location;
 183         struct timeval stop_time;
 184         enum tevent_req_state state;
 185         uint64_t user_error;
 186         struct tevent_req_profile *subprofiles;
 187 };
 188
 189 struct tevent_fd {
 190         struct tevent_fd *prev, *next;
 191         struct tevent_context *event_ctx;
 192         struct tevent_wrapper_glue *wrapper;
 193         bool busy;
 194         bool destroyed;
 195         int fd;
 196         uint16_t flags; /* see TEVENT_FD_* flags */
 197         tevent_fd_handler_t handler;
 198         tevent_fd_close_fn_t close_fn;
 199         /* this is private for the specific handler */
 200         void *private_data;
 201         /* this is for debugging only! */
 202         const char *handler_name;
 203         const char *location;
 204         /* this is private for the events_ops implementation */
 205         uint64_t additional_flags;
 206         void *additional_data;
 207 };
 208
 209 struct tevent_timer {
 210         struct tevent_timer *prev, *next;
 211         struct tevent_context *event_ctx;
 212         struct tevent_wrapper_glue *wrapper;
 213         bool busy;
 214         bool destroyed;
 215         struct timeval next_event;
 216         tevent_timer_handler_t handler;
 217         /* this is private for the specific handler */
 218         void *private_data;
 219         /* this is for debugging only! */
 220         const char *handler_name;
 221         const char *location;
 222         /* this is private for the events_ops implementation */
 223         void *additional_data;
 224 };
 225
 226 struct tevent_immediate {
 227         struct tevent_immediate *prev, *next;
 228         struct tevent_context *event_ctx;
 229         struct tevent_wrapper_glue *wrapper;
 230         bool busy;
 231         bool destroyed;
 232         tevent_immediate_handler_t handler;
 233         /* this is private for the specific handler */
 234         void *private_data;
 235         /* this is for debugging only! */
 236         const char *handler_name;
 237         const char *create_location;
 238         const char *schedule_location;
 239         /* this is private for the events_ops implementation */
 240         void (*cancel_fn)(struct tevent_immediate *im);
 241         void *additional_data;
 242 };
 243
 244 struct tevent_signal {
 245         struct tevent_signal *prev, *next;
 246         struct tevent_context *event_ctx;
 247         struct tevent_wrapper_glue *wrapper;
 248         bool busy;
 249         bool destroyed;
 250         int signum;
 251         int sa_flags;
 252         tevent_signal_handler_t handler;
 253         /* this is private for the specific handler */
 254         void *private_data;
 255         /* this is for debugging only! */
 256         const char *handler_name;
 257         const char *location;
 258         /* this is private for the events_ops implementation */
 259         void *additional_data;
 260 };
 261
 262 struct tevent_threaded_context {
 263         struct tevent_threaded_context *next, *prev;
 264
 265 #ifdef HAVE_PTHREAD
 266         pthread_mutex_t event_ctx_mutex;
 267 #endif
 268         struct tevent_context *event_ctx;
 269 };
 270
 271 struct tevent_debug_ops {
 272         void (*debug)(void *context, enum tevent_debug_level level,
 273                       const char *fmt, va_list ap) PRINTF_ATTRIBUTE(3,0);
 274         void *context;
 275 };
 276
 277 void tevent_debug(struct tevent_context *ev, enum tevent_debug_level level,
 278                   const char *fmt, ...) PRINTF_ATTRIBUTE(3,4);
 279
 280 void tevent_abort(struct tevent_context *ev, const char *reason);
 281
 282 void tevent_common_check_double_free(TALLOC_CTX *ptr, const char *reason);
 283
 284 struct tevent_context {
 285         /* the specific events implementation */
 286         const struct tevent_ops *ops;
 287
 288         /*
 289          * The following three pointers are queried on every loop_once
 290          * in the order in which they appear here. Not measured, but
 291          * hopefully putting them at the top together with "ops"
 292          * should make tevent a *bit* more cache-friendly than before.
 293          */
 294
 295         /* list of signal events - used by common code */
 296         struct tevent_signal *signal_events;
 297
 298         /* List of threaded job indicators */
 299         struct tevent_threaded_context *threaded_contexts;
 300
 301         /* list of immediate events - used by common code */
 302         struct tevent_immediate *immediate_events;
 303
 304         /* list of fd events - used by common code */
 305         struct tevent_fd *fd_events;
 306
 307         /* list of timed events - used by common code */
 308         struct tevent_timer *timer_events;
 309
 310         /* List of scheduled immediates */
 311         pthread_mutex_t scheduled_mutex;
 312         struct tevent_immediate *scheduled_immediates;
 313
 314         /* this is private for the events_ops implementation */
 315         void *additional_data;
 316
 317         /* pipe hack used with signal handlers */
 318         struct tevent_fd *wakeup_fde;
 319         int wakeup_fd;          /* fd to write into */
 320 #ifndef HAVE_EVENT_FD
 321         int wakeup_read_fd;
 322 #endif
 323
 324         /* debugging operations */
 325         struct tevent_debug_ops debug_ops;
 326
 327         /* info about the nesting status */
 328         struct {
 329                 bool allowed;
 330                 uint32_t level;
 331                 tevent_nesting_hook hook_fn;
 332                 void *hook_private;
 333         } nesting;
 334
 335         struct {
 336                 tevent_trace_callback_t callback;
 337                 void *private_data;
 338         } tracing;
 339
 340         struct {
 341                 /*
 342                  * This is used on the main event context
 343                  */
 344                 struct tevent_wrapper_glue *list;
 345
 346                 /*
 347                  * This is used on the wrapper event context
 348                  */
 349                 struct tevent_wrapper_glue *glue;
 350         } wrapper;
 351
 352         /*
 353          * an optimization pointer into timer_events
 354          * used by used by common code via
 355          * tevent_common_add_timer_v2()
 356          */
 357         struct tevent_timer *last_zero_timer;
 358
 359 #ifdef HAVE_PTHREAD
 360         struct tevent_context *prev, *next;
 361 #endif
 362 };
 363
 364 const struct tevent_ops *tevent_find_ops_byname(const char *name);
 365
 366 int tevent_common_context_destructor(struct tevent_context *ev);
 367 int tevent_common_loop_wait(struct tevent_context *ev,
 368                             const char *location);
 369
 370 int tevent_common_fd_destructor(struct tevent_fd *fde);
 371 struct tevent_fd *tevent_common_add_fd(struct tevent_context *ev,
 372                                        TALLOC_CTX *mem_ctx,
 373                                        int fd,
 374                                        uint16_t flags,
 375                                        tevent_fd_handler_t handler,
 376                                        void *private_data,
 377                                        const char *handler_name,
 378                                        const char *location);
 379 void tevent_common_fd_set_close_fn(struct tevent_fd *fde,
 380                                    tevent_fd_close_fn_t close_fn);
 381 uint16_t tevent_common_fd_get_flags(struct tevent_fd *fde);
 382 void tevent_common_fd_set_flags(struct tevent_fd *fde, uint16_t flags);
 383 int tevent_common_invoke_fd_handler(struct tevent_fd *fde, uint16_t flags,
 384                                     bool *removed);
 385
 386 struct tevent_timer *tevent_common_add_timer(struct tevent_context *ev,
 387                                              TALLOC_CTX *mem_ctx,
 388                                              struct timeval next_event,
 389                                              tevent_timer_handler_t handler,
 390                                              void *private_data,
 391                                              const char *handler_name,
 392                                              const char *location);
 393 struct tevent_timer *tevent_common_add_timer_v2(struct tevent_context *ev,
 394                                                 TALLOC_CTX *mem_ctx,
 395                                                 struct timeval next_event,
 396                                                 tevent_timer_handler_t handler,
 397                                                 void *private_data,
 398                                                 const char *handler_name,
 399                                                 const char *location);
 400 struct timeval tevent_common_loop_timer_delay(struct tevent_context *);
 401 int tevent_common_invoke_timer_handler(struct tevent_timer *te,
 402                                        struct timeval current_time,
 403                                        bool *removed);
 404
 405 void tevent_common_schedule_immediate(struct tevent_immediate *im,
 406                                       struct tevent_context *ev,
 407                                       tevent_immediate_handler_t handler,
 408                                       void *private_data,
 409                                       const char *handler_name,
 410                                       const char *location);
 411 int tevent_common_invoke_immediate_handler(struct tevent_immediate *im,
 412                                            bool *removed);
 413 bool tevent_common_loop_immediate(struct tevent_context *ev);
 414 void tevent_common_threaded_activate_immediate(struct tevent_context *ev);
 415
 416 bool tevent_common_have_events(struct tevent_context *ev);
 417 int tevent_common_wakeup_init(struct tevent_context *ev);
 418 int tevent_common_wakeup_fd(int fd);
 419 int tevent_common_wakeup(struct tevent_context *ev);
 420
 421 struct tevent_signal *tevent_common_add_signal(struct tevent_context *ev,
 422                                                TALLOC_CTX *mem_ctx,
 423                                                int signum,
 424                                                int sa_flags,
 425                                                tevent_signal_handler_t handler,
 426                                                void *private_data,
 427                                                const char *handler_name,
 428                                                const char *location);
 429 int tevent_common_check_signal(struct tevent_context *ev);
 430 void tevent_cleanup_pending_signal_handlers(struct tevent_signal *se);
 431 int tevent_common_invoke_signal_handler(struct tevent_signal *se,
 432                                         int signum, int count, void *siginfo,
 433                                         bool *removed);
 434
 435 struct tevent_context *tevent_wrapper_main_ev(struct tevent_context *ev);
 436
 437 struct tevent_wrapper_ops;
 438
 439 struct tevent_wrapper_glue {
 440         struct tevent_wrapper_glue *prev, *next;
 441         struct tevent_context *wrap_ev;
 442         struct tevent_context *main_ev;
 443         bool busy;
 444         bool destroyed;
 445         const struct tevent_wrapper_ops *ops;
 446         void *private_state;
 447 };
 448
 449 void tevent_wrapper_push_use_internal(struct tevent_context *ev,
 450                                       struct tevent_wrapper_glue *wrapper);
 451 void tevent_wrapper_pop_use_internal(const struct tevent_context *__ev_ptr,
 452                                      struct tevent_wrapper_glue *wrapper);
 453
 454 bool tevent_standard_init(void);
 455 bool tevent_poll_init(void);
 456 bool tevent_poll_event_add_fd_internal(struct tevent_context *ev,
 457                                        struct tevent_fd *fde);
 458 bool tevent_poll_mt_init(void);
 459 #ifdef HAVE_EPOLL
 460 bool tevent_epoll_init(void);
 461 void tevent_epoll_set_panic_fallback(struct tevent_context *ev,
 462                         bool (*panic_fallback)(struct tevent_context *ev,
 463                                                bool replay));
 464 #endif
 465 #ifdef HAVE_SOLARIS_PORTS
 466 bool tevent_port_init(void);
 467 #endif
 468
 469
 470 void tevent_trace_point_callback(struct tevent_context *ev,
 471                                  enum tevent_trace_point);