| 1 | /* Event loop machinery for GDB, the GNU debugger. |
| 2 | Copyright 1999, 2000, 2001, 2002 Free Software Foundation, Inc. |
| 3 | Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 20 | Boston, MA 02111-1307, USA. */ |
| 21 | |
| 22 | #include "defs.h" |
| 23 | #include "event-loop.h" |
| 24 | #include "event-top.h" |
| 25 | |
| 26 | #ifdef HAVE_POLL |
| 27 | #if defined (HAVE_POLL_H) |
| 28 | #include <poll.h> |
| 29 | #elif defined (HAVE_SYS_POLL_H) |
| 30 | #include <sys/poll.h> |
| 31 | #endif |
| 32 | #endif |
| 33 | |
| 34 | #include <sys/types.h> |
| 35 | #include "gdb_string.h" |
| 36 | #include <errno.h> |
| 37 | #include <sys/time.h> |
| 38 | #include "exceptions.h" |
| 39 | #include "gdb_assert.h" |
| 40 | |
| 41 | typedef struct gdb_event gdb_event; |
| 42 | typedef void (event_handler_func) (int); |
| 43 | |
| 44 | /* Event for the GDB event system. Events are queued by calling |
| 45 | async_queue_event and serviced later on by gdb_do_one_event. An |
| 46 | event can be, for instance, a file descriptor becoming ready to be |
| 47 | read. Servicing an event simply means that the procedure PROC will |
| 48 | be called. We have 2 queues, one for file handlers that we listen |
| 49 | to in the event loop, and one for the file handlers+events that are |
| 50 | ready. The procedure PROC associated with each event is always the |
| 51 | same (handle_file_event). Its duty is to invoke the handler |
| 52 | associated with the file descriptor whose state change generated |
| 53 | the event, plus doing other cleanups and such. */ |
| 54 | |
| 55 | struct gdb_event |
| 56 | { |
| 57 | event_handler_func *proc; /* Procedure to call to service this event. */ |
| 58 | int fd; /* File descriptor that is ready. */ |
| 59 | struct gdb_event *next_event; /* Next in list of events or NULL. */ |
| 60 | }; |
| 61 | |
| 62 | /* Information about each file descriptor we register with the event |
| 63 | loop. */ |
| 64 | |
| 65 | typedef struct file_handler |
| 66 | { |
| 67 | int fd; /* File descriptor. */ |
| 68 | int mask; /* Events we want to monitor: POLLIN, etc. */ |
| 69 | int ready_mask; /* Events that have been seen since |
| 70 | the last time. */ |
| 71 | handler_func *proc; /* Procedure to call when fd is ready. */ |
| 72 | gdb_client_data client_data; /* Argument to pass to proc. */ |
| 73 | int error; /* Was an error detected on this fd? */ |
| 74 | struct file_handler *next_file; /* Next registered file descriptor. */ |
| 75 | } |
| 76 | file_handler; |
| 77 | |
| 78 | /* PROC is a function to be invoked when the READY flag is set. This |
| 79 | happens when there has been a signal and the corresponding signal |
| 80 | handler has 'triggered' this async_signal_handler for |
| 81 | execution. The actual work to be done in response to a signal will |
| 82 | be carried out by PROC at a later time, within process_event. This |
| 83 | provides a deferred execution of signal handlers. |
| 84 | Async_init_signals takes care of setting up such an |
| 85 | asyn_signal_handler for each interesting signal. */ |
| 86 | typedef struct async_signal_handler |
| 87 | { |
| 88 | int ready; /* If ready, call this handler from the main event loop, |
| 89 | using invoke_async_handler. */ |
| 90 | struct async_signal_handler *next_handler; /* Ptr to next handler */ |
| 91 | sig_handler_func *proc; /* Function to call to do the work */ |
| 92 | gdb_client_data client_data; /* Argument to async_handler_func */ |
| 93 | } |
| 94 | async_signal_handler; |
| 95 | |
| 96 | |
| 97 | /* Event queue: |
| 98 | - the first event in the queue is the head of the queue. |
| 99 | It will be the next to be serviced. |
| 100 | - the last event in the queue |
| 101 | |
| 102 | Events can be inserted at the front of the queue or at the end of |
| 103 | the queue. Events will be extracted from the queue for processing |
| 104 | starting from the head. Therefore, events inserted at the head of |
| 105 | the queue will be processed in a last in first out fashion, while |
| 106 | those inserted at the tail of the queue will be processed in a first |
| 107 | in first out manner. All the fields are NULL if the queue is |
| 108 | empty. */ |
| 109 | |
| 110 | static struct |
| 111 | { |
| 112 | gdb_event *first_event; /* First pending event */ |
| 113 | gdb_event *last_event; /* Last pending event */ |
| 114 | } |
| 115 | event_queue; |
| 116 | |
| 117 | /* Gdb_notifier is just a list of file descriptors gdb is interested in. |
| 118 | These are the input file descriptor, and the target file |
| 119 | descriptor. We have two flavors of the notifier, one for platforms |
| 120 | that have the POLL function, the other for those that don't, and |
| 121 | only support SELECT. Each of the elements in the gdb_notifier list is |
| 122 | basically a description of what kind of events gdb is interested |
| 123 | in, for each fd. */ |
| 124 | |
| 125 | /* As of 1999-04-30 only the input file descriptor is registered with the |
| 126 | event loop. */ |
| 127 | |
| 128 | /* Do we use poll or select ? */ |
| 129 | #ifdef HAVE_POLL |
| 130 | #define USE_POLL 1 |
| 131 | #else |
| 132 | #define USE_POLL 0 |
| 133 | #endif /* HAVE_POLL */ |
| 134 | |
| 135 | static unsigned char use_poll = USE_POLL; |
| 136 | |
| 137 | #ifdef USE_WIN32API |
| 138 | #include <windows.h> |
| 139 | #include <io.h> |
| 140 | #endif |
| 141 | |
| 142 | static struct |
| 143 | { |
| 144 | /* Ptr to head of file handler list. */ |
| 145 | file_handler *first_file_handler; |
| 146 | |
| 147 | #ifdef HAVE_POLL |
| 148 | /* Ptr to array of pollfd structures. */ |
| 149 | struct pollfd *poll_fds; |
| 150 | |
| 151 | /* Timeout in milliseconds for calls to poll(). */ |
| 152 | int poll_timeout; |
| 153 | #endif |
| 154 | |
| 155 | /* Masks to be used in the next call to select. |
| 156 | Bits are set in response to calls to create_file_handler. */ |
| 157 | fd_set check_masks[3]; |
| 158 | |
| 159 | /* What file descriptors were found ready by select. */ |
| 160 | fd_set ready_masks[3]; |
| 161 | |
| 162 | /* Number of file descriptors to monitor. (for poll) */ |
| 163 | /* Number of valid bits (highest fd value + 1). (for select) */ |
| 164 | int num_fds; |
| 165 | |
| 166 | /* Time structure for calls to select(). */ |
| 167 | struct timeval select_timeout; |
| 168 | |
| 169 | /* Flag to tell whether the timeout should be used. */ |
| 170 | int timeout_valid; |
| 171 | } |
| 172 | gdb_notifier; |
| 173 | |
| 174 | /* Structure associated with a timer. PROC will be executed at the |
| 175 | first occasion after WHEN. */ |
| 176 | struct gdb_timer |
| 177 | { |
| 178 | struct timeval when; |
| 179 | int timer_id; |
| 180 | struct gdb_timer *next; |
| 181 | timer_handler_func *proc; /* Function to call to do the work */ |
| 182 | gdb_client_data client_data; /* Argument to async_handler_func */ |
| 183 | } |
| 184 | gdb_timer; |
| 185 | |
| 186 | /* List of currently active timers. It is sorted in order of |
| 187 | increasing timers. */ |
| 188 | static struct |
| 189 | { |
| 190 | /* Pointer to first in timer list. */ |
| 191 | struct gdb_timer *first_timer; |
| 192 | |
| 193 | /* Id of the last timer created. */ |
| 194 | int num_timers; |
| 195 | } |
| 196 | timer_list; |
| 197 | |
| 198 | /* All the async_signal_handlers gdb is interested in are kept onto |
| 199 | this list. */ |
| 200 | static struct |
| 201 | { |
| 202 | /* Pointer to first in handler list. */ |
| 203 | async_signal_handler *first_handler; |
| 204 | |
| 205 | /* Pointer to last in handler list. */ |
| 206 | async_signal_handler *last_handler; |
| 207 | } |
| 208 | sighandler_list; |
| 209 | |
| 210 | /* Are any of the handlers ready? Check this variable using |
| 211 | check_async_ready. This is used by process_event, to determine |
| 212 | whether or not to invoke the invoke_async_signal_handler |
| 213 | function. */ |
| 214 | static int async_handler_ready = 0; |
| 215 | |
| 216 | static void create_file_handler (int fd, int mask, handler_func * proc, gdb_client_data client_data); |
| 217 | static void invoke_async_signal_handler (void); |
| 218 | static void handle_file_event (int event_file_desc); |
| 219 | static int gdb_wait_for_event (void); |
| 220 | static int check_async_ready (void); |
| 221 | static void async_queue_event (gdb_event * event_ptr, queue_position position); |
| 222 | static gdb_event *create_file_event (int fd); |
| 223 | static int process_event (void); |
| 224 | static void handle_timer_event (int dummy); |
| 225 | static void poll_timers (void); |
| 226 | \f |
| 227 | |
| 228 | /* Insert an event object into the gdb event queue at |
| 229 | the specified position. |
| 230 | POSITION can be head or tail, with values TAIL, HEAD. |
| 231 | EVENT_PTR points to the event to be inserted into the queue. |
| 232 | The caller must allocate memory for the event. It is freed |
| 233 | after the event has ben handled. |
| 234 | Events in the queue will be processed head to tail, therefore, |
| 235 | events inserted at the head of the queue will be processed |
| 236 | as last in first out. Event appended at the tail of the queue |
| 237 | will be processed first in first out. */ |
| 238 | static void |
| 239 | async_queue_event (gdb_event * event_ptr, queue_position position) |
| 240 | { |
| 241 | if (position == TAIL) |
| 242 | { |
| 243 | /* The event will become the new last_event. */ |
| 244 | |
| 245 | event_ptr->next_event = NULL; |
| 246 | if (event_queue.first_event == NULL) |
| 247 | event_queue.first_event = event_ptr; |
| 248 | else |
| 249 | event_queue.last_event->next_event = event_ptr; |
| 250 | event_queue.last_event = event_ptr; |
| 251 | } |
| 252 | else if (position == HEAD) |
| 253 | { |
| 254 | /* The event becomes the new first_event. */ |
| 255 | |
| 256 | event_ptr->next_event = event_queue.first_event; |
| 257 | if (event_queue.first_event == NULL) |
| 258 | event_queue.last_event = event_ptr; |
| 259 | event_queue.first_event = event_ptr; |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | /* Create a file event, to be enqueued in the event queue for |
| 264 | processing. The procedure associated to this event is always |
| 265 | handle_file_event, which will in turn invoke the one that was |
| 266 | associated to FD when it was registered with the event loop. */ |
| 267 | static gdb_event * |
| 268 | create_file_event (int fd) |
| 269 | { |
| 270 | gdb_event *file_event_ptr; |
| 271 | |
| 272 | file_event_ptr = (gdb_event *) xmalloc (sizeof (gdb_event)); |
| 273 | file_event_ptr->proc = handle_file_event; |
| 274 | file_event_ptr->fd = fd; |
| 275 | return (file_event_ptr); |
| 276 | } |
| 277 | |
| 278 | /* Process one event. |
| 279 | The event can be the next one to be serviced in the event queue, |
| 280 | or an asynchronous event handler can be invoked in response to |
| 281 | the reception of a signal. |
| 282 | If an event was processed (either way), 1 is returned otherwise |
| 283 | 0 is returned. |
| 284 | Scan the queue from head to tail, processing therefore the high |
| 285 | priority events first, by invoking the associated event handler |
| 286 | procedure. */ |
| 287 | static int |
| 288 | process_event (void) |
| 289 | { |
| 290 | gdb_event *event_ptr, *prev_ptr; |
| 291 | event_handler_func *proc; |
| 292 | int fd; |
| 293 | |
| 294 | /* First let's see if there are any asynchronous event handlers that |
| 295 | are ready. These would be the result of invoking any of the |
| 296 | signal handlers. */ |
| 297 | |
| 298 | if (check_async_ready ()) |
| 299 | { |
| 300 | invoke_async_signal_handler (); |
| 301 | return 1; |
| 302 | } |
| 303 | |
| 304 | /* Look in the event queue to find an event that is ready |
| 305 | to be processed. */ |
| 306 | |
| 307 | for (event_ptr = event_queue.first_event; event_ptr != NULL; |
| 308 | event_ptr = event_ptr->next_event) |
| 309 | { |
| 310 | /* Call the handler for the event. */ |
| 311 | |
| 312 | proc = event_ptr->proc; |
| 313 | fd = event_ptr->fd; |
| 314 | |
| 315 | /* Let's get rid of the event from the event queue. We need to |
| 316 | do this now because while processing the event, the proc |
| 317 | function could end up calling 'error' and therefore jump out |
| 318 | to the caller of this function, gdb_do_one_event. In that |
| 319 | case, we would have on the event queue an event wich has been |
| 320 | processed, but not deleted. */ |
| 321 | |
| 322 | if (event_queue.first_event == event_ptr) |
| 323 | { |
| 324 | event_queue.first_event = event_ptr->next_event; |
| 325 | if (event_ptr->next_event == NULL) |
| 326 | event_queue.last_event = NULL; |
| 327 | } |
| 328 | else |
| 329 | { |
| 330 | prev_ptr = event_queue.first_event; |
| 331 | while (prev_ptr->next_event != event_ptr) |
| 332 | prev_ptr = prev_ptr->next_event; |
| 333 | |
| 334 | prev_ptr->next_event = event_ptr->next_event; |
| 335 | if (event_ptr->next_event == NULL) |
| 336 | event_queue.last_event = prev_ptr; |
| 337 | } |
| 338 | xfree (event_ptr); |
| 339 | |
| 340 | /* Now call the procedure associated with the event. */ |
| 341 | (*proc) (fd); |
| 342 | return 1; |
| 343 | } |
| 344 | |
| 345 | /* this is the case if there are no event on the event queue. */ |
| 346 | return 0; |
| 347 | } |
| 348 | |
| 349 | /* Process one high level event. If nothing is ready at this time, |
| 350 | wait for something to happen (via gdb_wait_for_event), then process |
| 351 | it. Returns >0 if something was done otherwise returns <0 (this |
| 352 | can happen if there are no event sources to wait for). If an error |
| 353 | occurs catch_errors() which calls this function returns zero. */ |
| 354 | |
| 355 | int |
| 356 | gdb_do_one_event (void *data) |
| 357 | { |
| 358 | /* Any events already waiting in the queue? */ |
| 359 | if (process_event ()) |
| 360 | { |
| 361 | return 1; |
| 362 | } |
| 363 | |
| 364 | /* Are any timers that are ready? If so, put an event on the queue. */ |
| 365 | poll_timers (); |
| 366 | |
| 367 | /* Wait for a new event. If gdb_wait_for_event returns -1, |
| 368 | we should get out because this means that there are no |
| 369 | event sources left. This will make the event loop stop, |
| 370 | and the application exit. */ |
| 371 | |
| 372 | if (gdb_wait_for_event () < 0) |
| 373 | { |
| 374 | return -1; |
| 375 | } |
| 376 | |
| 377 | /* Handle any new events occurred while waiting. */ |
| 378 | if (process_event ()) |
| 379 | { |
| 380 | return 1; |
| 381 | } |
| 382 | |
| 383 | /* If gdb_wait_for_event has returned 1, it means that one |
| 384 | event has been handled. We break out of the loop. */ |
| 385 | return 1; |
| 386 | } |
| 387 | |
| 388 | /* Start up the event loop. This is the entry point to the event loop |
| 389 | from the command loop. */ |
| 390 | |
| 391 | void |
| 392 | start_event_loop (void) |
| 393 | { |
| 394 | /* Loop until there is nothing to do. This is the entry point to the |
| 395 | event loop engine. gdb_do_one_event, called via catch_errors() |
| 396 | will process one event for each invocation. It blocks waits for |
| 397 | an event and then processes it. >0 when an event is processed, 0 |
| 398 | when catch_errors() caught an error and <0 when there are no |
| 399 | longer any event sources registered. */ |
| 400 | while (1) |
| 401 | { |
| 402 | int gdb_result; |
| 403 | |
| 404 | gdb_result = catch_errors (gdb_do_one_event, 0, "", RETURN_MASK_ALL); |
| 405 | if (gdb_result < 0) |
| 406 | break; |
| 407 | |
| 408 | /* If we long-jumped out of do_one_event, we probably |
| 409 | didn't get around to resetting the prompt, which leaves |
| 410 | readline in a messed-up state. Reset it here. */ |
| 411 | |
| 412 | if (gdb_result == 0) |
| 413 | { |
| 414 | /* FIXME: this should really be a call to a hook that is |
| 415 | interface specific, because interfaces can display the |
| 416 | prompt in their own way. */ |
| 417 | display_gdb_prompt (0); |
| 418 | /* This call looks bizarre, but it is required. If the user |
| 419 | entered a command that caused an error, |
| 420 | after_char_processing_hook won't be called from |
| 421 | rl_callback_read_char_wrapper. Using a cleanup there |
| 422 | won't work, since we want this function to be called |
| 423 | after a new prompt is printed. */ |
| 424 | if (after_char_processing_hook) |
| 425 | (*after_char_processing_hook) (); |
| 426 | /* Maybe better to set a flag to be checked somewhere as to |
| 427 | whether display the prompt or not. */ |
| 428 | } |
| 429 | } |
| 430 | |
| 431 | /* We are done with the event loop. There are no more event sources |
| 432 | to listen to. So we exit GDB. */ |
| 433 | return; |
| 434 | } |
| 435 | \f |
| 436 | |
| 437 | /* Wrapper function for create_file_handler, so that the caller |
| 438 | doesn't have to know implementation details about the use of poll |
| 439 | vs. select. */ |
| 440 | void |
| 441 | add_file_handler (int fd, handler_func * proc, gdb_client_data client_data) |
| 442 | { |
| 443 | #ifdef HAVE_POLL |
| 444 | struct pollfd fds; |
| 445 | #endif |
| 446 | |
| 447 | if (use_poll) |
| 448 | { |
| 449 | #ifdef HAVE_POLL |
| 450 | /* Check to see if poll () is usable. If not, we'll switch to |
| 451 | use select. This can happen on systems like |
| 452 | m68k-motorola-sys, `poll' cannot be used to wait for `stdin'. |
| 453 | On m68k-motorola-sysv, tty's are not stream-based and not |
| 454 | `poll'able. */ |
| 455 | fds.fd = fd; |
| 456 | fds.events = POLLIN; |
| 457 | if (poll (&fds, 1, 0) == 1 && (fds.revents & POLLNVAL)) |
| 458 | use_poll = 0; |
| 459 | #else |
| 460 | internal_error (__FILE__, __LINE__, |
| 461 | _("use_poll without HAVE_POLL")); |
| 462 | #endif /* HAVE_POLL */ |
| 463 | } |
| 464 | if (use_poll) |
| 465 | { |
| 466 | #ifdef HAVE_POLL |
| 467 | create_file_handler (fd, POLLIN, proc, client_data); |
| 468 | #else |
| 469 | internal_error (__FILE__, __LINE__, |
| 470 | _("use_poll without HAVE_POLL")); |
| 471 | #endif |
| 472 | } |
| 473 | else |
| 474 | create_file_handler (fd, GDB_READABLE | GDB_EXCEPTION, proc, client_data); |
| 475 | } |
| 476 | |
| 477 | /* Add a file handler/descriptor to the list of descriptors we are |
| 478 | interested in. |
| 479 | FD is the file descriptor for the file/stream to be listened to. |
| 480 | For the poll case, MASK is a combination (OR) of |
| 481 | POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM, |
| 482 | POLLWRBAND: these are the events we are interested in. If any of them |
| 483 | occurs, proc should be called. |
| 484 | For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION. |
| 485 | PROC is the procedure that will be called when an event occurs for |
| 486 | FD. CLIENT_DATA is the argument to pass to PROC. */ |
| 487 | static void |
| 488 | create_file_handler (int fd, int mask, handler_func * proc, gdb_client_data client_data) |
| 489 | { |
| 490 | file_handler *file_ptr; |
| 491 | |
| 492 | /* Do we already have a file handler for this file? (We may be |
| 493 | changing its associated procedure). */ |
| 494 | for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; |
| 495 | file_ptr = file_ptr->next_file) |
| 496 | { |
| 497 | if (file_ptr->fd == fd) |
| 498 | break; |
| 499 | } |
| 500 | |
| 501 | /* It is a new file descriptor. Add it to the list. Otherwise, just |
| 502 | change the data associated with it. */ |
| 503 | if (file_ptr == NULL) |
| 504 | { |
| 505 | file_ptr = (file_handler *) xmalloc (sizeof (file_handler)); |
| 506 | file_ptr->fd = fd; |
| 507 | file_ptr->ready_mask = 0; |
| 508 | file_ptr->next_file = gdb_notifier.first_file_handler; |
| 509 | gdb_notifier.first_file_handler = file_ptr; |
| 510 | |
| 511 | if (use_poll) |
| 512 | { |
| 513 | #ifdef HAVE_POLL |
| 514 | gdb_notifier.num_fds++; |
| 515 | if (gdb_notifier.poll_fds) |
| 516 | gdb_notifier.poll_fds = |
| 517 | (struct pollfd *) xrealloc (gdb_notifier.poll_fds, |
| 518 | (gdb_notifier.num_fds |
| 519 | * sizeof (struct pollfd))); |
| 520 | else |
| 521 | gdb_notifier.poll_fds = |
| 522 | (struct pollfd *) xmalloc (sizeof (struct pollfd)); |
| 523 | (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->fd = fd; |
| 524 | (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->events = mask; |
| 525 | (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->revents = 0; |
| 526 | #else |
| 527 | internal_error (__FILE__, __LINE__, |
| 528 | _("use_poll without HAVE_POLL")); |
| 529 | #endif /* HAVE_POLL */ |
| 530 | } |
| 531 | else |
| 532 | { |
| 533 | if (mask & GDB_READABLE) |
| 534 | FD_SET (fd, &gdb_notifier.check_masks[0]); |
| 535 | else |
| 536 | FD_CLR (fd, &gdb_notifier.check_masks[0]); |
| 537 | |
| 538 | if (mask & GDB_WRITABLE) |
| 539 | FD_SET (fd, &gdb_notifier.check_masks[1]); |
| 540 | else |
| 541 | FD_CLR (fd, &gdb_notifier.check_masks[1]); |
| 542 | |
| 543 | if (mask & GDB_EXCEPTION) |
| 544 | FD_SET (fd, &gdb_notifier.check_masks[2]); |
| 545 | else |
| 546 | FD_CLR (fd, &gdb_notifier.check_masks[2]); |
| 547 | |
| 548 | if (gdb_notifier.num_fds <= fd) |
| 549 | gdb_notifier.num_fds = fd + 1; |
| 550 | } |
| 551 | } |
| 552 | |
| 553 | file_ptr->proc = proc; |
| 554 | file_ptr->client_data = client_data; |
| 555 | file_ptr->mask = mask; |
| 556 | } |
| 557 | |
| 558 | /* Remove the file descriptor FD from the list of monitored fd's: |
| 559 | i.e. we don't care anymore about events on the FD. */ |
| 560 | void |
| 561 | delete_file_handler (int fd) |
| 562 | { |
| 563 | file_handler *file_ptr, *prev_ptr = NULL; |
| 564 | int i; |
| 565 | #ifdef HAVE_POLL |
| 566 | int j; |
| 567 | struct pollfd *new_poll_fds; |
| 568 | #endif |
| 569 | |
| 570 | /* Find the entry for the given file. */ |
| 571 | |
| 572 | for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; |
| 573 | file_ptr = file_ptr->next_file) |
| 574 | { |
| 575 | if (file_ptr->fd == fd) |
| 576 | break; |
| 577 | } |
| 578 | |
| 579 | if (file_ptr == NULL) |
| 580 | return; |
| 581 | |
| 582 | if (use_poll) |
| 583 | { |
| 584 | #ifdef HAVE_POLL |
| 585 | /* Create a new poll_fds array by copying every fd's information but the |
| 586 | one we want to get rid of. */ |
| 587 | |
| 588 | new_poll_fds = |
| 589 | (struct pollfd *) xmalloc ((gdb_notifier.num_fds - 1) * sizeof (struct pollfd)); |
| 590 | |
| 591 | for (i = 0, j = 0; i < gdb_notifier.num_fds; i++) |
| 592 | { |
| 593 | if ((gdb_notifier.poll_fds + i)->fd != fd) |
| 594 | { |
| 595 | (new_poll_fds + j)->fd = (gdb_notifier.poll_fds + i)->fd; |
| 596 | (new_poll_fds + j)->events = (gdb_notifier.poll_fds + i)->events; |
| 597 | (new_poll_fds + j)->revents = (gdb_notifier.poll_fds + i)->revents; |
| 598 | j++; |
| 599 | } |
| 600 | } |
| 601 | xfree (gdb_notifier.poll_fds); |
| 602 | gdb_notifier.poll_fds = new_poll_fds; |
| 603 | gdb_notifier.num_fds--; |
| 604 | #else |
| 605 | internal_error (__FILE__, __LINE__, |
| 606 | _("use_poll without HAVE_POLL")); |
| 607 | #endif /* HAVE_POLL */ |
| 608 | } |
| 609 | else |
| 610 | { |
| 611 | if (file_ptr->mask & GDB_READABLE) |
| 612 | FD_CLR (fd, &gdb_notifier.check_masks[0]); |
| 613 | if (file_ptr->mask & GDB_WRITABLE) |
| 614 | FD_CLR (fd, &gdb_notifier.check_masks[1]); |
| 615 | if (file_ptr->mask & GDB_EXCEPTION) |
| 616 | FD_CLR (fd, &gdb_notifier.check_masks[2]); |
| 617 | |
| 618 | /* Find current max fd. */ |
| 619 | |
| 620 | if ((fd + 1) == gdb_notifier.num_fds) |
| 621 | { |
| 622 | gdb_notifier.num_fds--; |
| 623 | for (i = gdb_notifier.num_fds; i; i--) |
| 624 | { |
| 625 | if (FD_ISSET (i - 1, &gdb_notifier.check_masks[0]) |
| 626 | || FD_ISSET (i - 1, &gdb_notifier.check_masks[1]) |
| 627 | || FD_ISSET (i - 1, &gdb_notifier.check_masks[2])) |
| 628 | break; |
| 629 | } |
| 630 | gdb_notifier.num_fds = i; |
| 631 | } |
| 632 | } |
| 633 | |
| 634 | /* Deactivate the file descriptor, by clearing its mask, |
| 635 | so that it will not fire again. */ |
| 636 | |
| 637 | file_ptr->mask = 0; |
| 638 | |
| 639 | /* Get rid of the file handler in the file handler list. */ |
| 640 | if (file_ptr == gdb_notifier.first_file_handler) |
| 641 | gdb_notifier.first_file_handler = file_ptr->next_file; |
| 642 | else |
| 643 | { |
| 644 | for (prev_ptr = gdb_notifier.first_file_handler; |
| 645 | prev_ptr->next_file != file_ptr; |
| 646 | prev_ptr = prev_ptr->next_file) |
| 647 | ; |
| 648 | prev_ptr->next_file = file_ptr->next_file; |
| 649 | } |
| 650 | xfree (file_ptr); |
| 651 | } |
| 652 | |
| 653 | /* Handle the given event by calling the procedure associated to the |
| 654 | corresponding file handler. Called by process_event indirectly, |
| 655 | through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the |
| 656 | event in the front of the event queue. */ |
| 657 | static void |
| 658 | handle_file_event (int event_file_desc) |
| 659 | { |
| 660 | file_handler *file_ptr; |
| 661 | int mask; |
| 662 | #ifdef HAVE_POLL |
| 663 | int error_mask; |
| 664 | int error_mask_returned; |
| 665 | #endif |
| 666 | |
| 667 | /* Search the file handler list to find one that matches the fd in |
| 668 | the event. */ |
| 669 | for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; |
| 670 | file_ptr = file_ptr->next_file) |
| 671 | { |
| 672 | if (file_ptr->fd == event_file_desc) |
| 673 | { |
| 674 | /* With poll, the ready_mask could have any of three events |
| 675 | set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot |
| 676 | be used in the requested event mask (events), but they |
| 677 | can be returned in the return mask (revents). We need to |
| 678 | check for those event too, and add them to the mask which |
| 679 | will be passed to the handler. */ |
| 680 | |
| 681 | /* See if the desired events (mask) match the received |
| 682 | events (ready_mask). */ |
| 683 | |
| 684 | if (use_poll) |
| 685 | { |
| 686 | #ifdef HAVE_POLL |
| 687 | error_mask = POLLHUP | POLLERR | POLLNVAL; |
| 688 | mask = (file_ptr->ready_mask & file_ptr->mask) | |
| 689 | (file_ptr->ready_mask & error_mask); |
| 690 | error_mask_returned = mask & error_mask; |
| 691 | |
| 692 | if (error_mask_returned != 0) |
| 693 | { |
| 694 | /* Work in progress. We may need to tell somebody what |
| 695 | kind of error we had. */ |
| 696 | if (error_mask_returned & POLLHUP) |
| 697 | printf_unfiltered (_("Hangup detected on fd %d\n"), file_ptr->fd); |
| 698 | if (error_mask_returned & POLLERR) |
| 699 | printf_unfiltered (_("Error detected on fd %d\n"), file_ptr->fd); |
| 700 | if (error_mask_returned & POLLNVAL) |
| 701 | printf_unfiltered (_("Invalid or non-`poll'able fd %d\n"), file_ptr->fd); |
| 702 | file_ptr->error = 1; |
| 703 | } |
| 704 | else |
| 705 | file_ptr->error = 0; |
| 706 | #else |
| 707 | internal_error (__FILE__, __LINE__, |
| 708 | _("use_poll without HAVE_POLL")); |
| 709 | #endif /* HAVE_POLL */ |
| 710 | } |
| 711 | else |
| 712 | { |
| 713 | if (file_ptr->ready_mask & GDB_EXCEPTION) |
| 714 | { |
| 715 | printf_unfiltered (_("Exception condition detected on fd %d\n"), file_ptr->fd); |
| 716 | file_ptr->error = 1; |
| 717 | } |
| 718 | else |
| 719 | file_ptr->error = 0; |
| 720 | mask = file_ptr->ready_mask & file_ptr->mask; |
| 721 | } |
| 722 | |
| 723 | /* Clear the received events for next time around. */ |
| 724 | file_ptr->ready_mask = 0; |
| 725 | |
| 726 | /* If there was a match, then call the handler. */ |
| 727 | if (mask != 0) |
| 728 | (*file_ptr->proc) (file_ptr->error, file_ptr->client_data); |
| 729 | break; |
| 730 | } |
| 731 | } |
| 732 | } |
| 733 | |
| 734 | /* Wrapper for select. This function is not yet exported from this |
| 735 | file because it is not sufficiently general. For example, |
| 736 | ser-base.c uses select to check for socket activity, and this |
| 737 | function does not support sockets under Windows, so we do not want |
| 738 | to use gdb_select in ser-base.c. */ |
| 739 | |
| 740 | static int |
| 741 | gdb_select (int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, |
| 742 | struct timeval *timeout) |
| 743 | { |
| 744 | #ifdef USE_WIN32API |
| 745 | HANDLE handles[MAXIMUM_WAIT_OBJECTS]; |
| 746 | HANDLE h; |
| 747 | DWORD event; |
| 748 | DWORD num_handles; |
| 749 | int fd; |
| 750 | int num_ready; |
| 751 | |
| 752 | num_handles = 0; |
| 753 | for (fd = 0; fd < n; ++fd) |
| 754 | { |
| 755 | /* EXCEPTFDS is silently ignored. GDB always sets GDB_EXCEPTION |
| 756 | when calling add_file_handler, but there is no natural analog |
| 757 | under Windows. */ |
| 758 | /* There is no support yet for WRITEFDS. At present, this isn't |
| 759 | used by GDB -- but we do not want to silently ignore WRITEFDS |
| 760 | if something starts using it. */ |
| 761 | gdb_assert (!FD_ISSET (fd, writefds)); |
| 762 | if (FD_ISSET (fd, readfds)) |
| 763 | { |
| 764 | gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS); |
| 765 | handles[num_handles++] = (HANDLE) _get_osfhandle (fd); |
| 766 | } |
| 767 | } |
| 768 | event = WaitForMultipleObjects (num_handles, |
| 769 | handles, |
| 770 | FALSE, |
| 771 | timeout |
| 772 | ? (timeout->tv_sec * 1000 + timeout->tv_usec) |
| 773 | : INFINITE); |
| 774 | /* EVENT can only be a value in the WAIT_ABANDONED_0 range if the |
| 775 | HANDLES included an abandoned mutex. Since GDB doesn't use |
| 776 | mutexes, that should never occur. */ |
| 777 | gdb_assert (!(WAIT_ABANDONED_0 <= event |
| 778 | && event < WAIT_ABANDONED_0 + num_handles)); |
| 779 | if (event == WAIT_FAILED) |
| 780 | return -1; |
| 781 | if (event == WAIT_TIMEOUT) |
| 782 | return 0; |
| 783 | /* Run through the READFDS, clearing bits corresponding to descriptors |
| 784 | for which input is unavailable. */ |
| 785 | num_ready = num_handles; |
| 786 | h = handles[event - WAIT_OBJECT_0]; |
| 787 | for (fd = 0; fd < n; ++fd) |
| 788 | { |
| 789 | HANDLE fd_h; |
| 790 | if (!FD_ISSET (fd, readfds)) |
| 791 | continue; |
| 792 | fd_h = (HANDLE) _get_osfhandle (fd); |
| 793 | /* This handle might be ready, even though it wasn't the handle |
| 794 | returned by WaitForMultipleObjects. */ |
| 795 | if (fd_h != h && WaitForSingleObject (fd_h, 0) != WAIT_OBJECT_0) |
| 796 | { |
| 797 | FD_CLR (fd, readfds); |
| 798 | --num_ready; |
| 799 | } |
| 800 | } |
| 801 | /* We never report any descriptors available for writing or with |
| 802 | exceptional conditions. */ |
| 803 | FD_ZERO (writefds); |
| 804 | FD_ZERO (exceptfds); |
| 805 | |
| 806 | return num_ready; |
| 807 | #else |
| 808 | return select (n, readfds, writefds, exceptfds, timeout); |
| 809 | #endif |
| 810 | } |
| 811 | |
| 812 | /* Called by gdb_do_one_event to wait for new events on the |
| 813 | monitored file descriptors. Queue file events as they are |
| 814 | detected by the poll. |
| 815 | If there are no events, this function will block in the |
| 816 | call to poll. |
| 817 | Return -1 if there are no files descriptors to monitor, |
| 818 | otherwise return 0. */ |
| 819 | static int |
| 820 | gdb_wait_for_event (void) |
| 821 | { |
| 822 | file_handler *file_ptr; |
| 823 | gdb_event *file_event_ptr; |
| 824 | int num_found = 0; |
| 825 | int i; |
| 826 | |
| 827 | /* Make sure all output is done before getting another event. */ |
| 828 | gdb_flush (gdb_stdout); |
| 829 | gdb_flush (gdb_stderr); |
| 830 | |
| 831 | if (gdb_notifier.num_fds == 0) |
| 832 | return -1; |
| 833 | |
| 834 | if (use_poll) |
| 835 | { |
| 836 | #ifdef HAVE_POLL |
| 837 | num_found = |
| 838 | poll (gdb_notifier.poll_fds, |
| 839 | (unsigned long) gdb_notifier.num_fds, |
| 840 | gdb_notifier.timeout_valid ? gdb_notifier.poll_timeout : -1); |
| 841 | |
| 842 | /* Don't print anything if we get out of poll because of a |
| 843 | signal. */ |
| 844 | if (num_found == -1 && errno != EINTR) |
| 845 | perror_with_name (("poll")); |
| 846 | #else |
| 847 | internal_error (__FILE__, __LINE__, |
| 848 | _("use_poll without HAVE_POLL")); |
| 849 | #endif /* HAVE_POLL */ |
| 850 | } |
| 851 | else |
| 852 | { |
| 853 | gdb_notifier.ready_masks[0] = gdb_notifier.check_masks[0]; |
| 854 | gdb_notifier.ready_masks[1] = gdb_notifier.check_masks[1]; |
| 855 | gdb_notifier.ready_masks[2] = gdb_notifier.check_masks[2]; |
| 856 | num_found = gdb_select (gdb_notifier.num_fds, |
| 857 | &gdb_notifier.ready_masks[0], |
| 858 | &gdb_notifier.ready_masks[1], |
| 859 | &gdb_notifier.ready_masks[2], |
| 860 | gdb_notifier.timeout_valid |
| 861 | ? &gdb_notifier.select_timeout : NULL); |
| 862 | |
| 863 | /* Clear the masks after an error from select. */ |
| 864 | if (num_found == -1) |
| 865 | { |
| 866 | FD_ZERO (&gdb_notifier.ready_masks[0]); |
| 867 | FD_ZERO (&gdb_notifier.ready_masks[1]); |
| 868 | FD_ZERO (&gdb_notifier.ready_masks[2]); |
| 869 | /* Dont print anything is we got a signal, let gdb handle it. */ |
| 870 | if (errno != EINTR) |
| 871 | perror_with_name (("select")); |
| 872 | } |
| 873 | } |
| 874 | |
| 875 | /* Enqueue all detected file events. */ |
| 876 | |
| 877 | if (use_poll) |
| 878 | { |
| 879 | #ifdef HAVE_POLL |
| 880 | for (i = 0; (i < gdb_notifier.num_fds) && (num_found > 0); i++) |
| 881 | { |
| 882 | if ((gdb_notifier.poll_fds + i)->revents) |
| 883 | num_found--; |
| 884 | else |
| 885 | continue; |
| 886 | |
| 887 | for (file_ptr = gdb_notifier.first_file_handler; |
| 888 | file_ptr != NULL; |
| 889 | file_ptr = file_ptr->next_file) |
| 890 | { |
| 891 | if (file_ptr->fd == (gdb_notifier.poll_fds + i)->fd) |
| 892 | break; |
| 893 | } |
| 894 | |
| 895 | if (file_ptr) |
| 896 | { |
| 897 | /* Enqueue an event only if this is still a new event for |
| 898 | this fd. */ |
| 899 | if (file_ptr->ready_mask == 0) |
| 900 | { |
| 901 | file_event_ptr = create_file_event (file_ptr->fd); |
| 902 | async_queue_event (file_event_ptr, TAIL); |
| 903 | } |
| 904 | } |
| 905 | |
| 906 | file_ptr->ready_mask = (gdb_notifier.poll_fds + i)->revents; |
| 907 | } |
| 908 | #else |
| 909 | internal_error (__FILE__, __LINE__, |
| 910 | _("use_poll without HAVE_POLL")); |
| 911 | #endif /* HAVE_POLL */ |
| 912 | } |
| 913 | else |
| 914 | { |
| 915 | for (file_ptr = gdb_notifier.first_file_handler; |
| 916 | (file_ptr != NULL) && (num_found > 0); |
| 917 | file_ptr = file_ptr->next_file) |
| 918 | { |
| 919 | int mask = 0; |
| 920 | |
| 921 | if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[0])) |
| 922 | mask |= GDB_READABLE; |
| 923 | if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[1])) |
| 924 | mask |= GDB_WRITABLE; |
| 925 | if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[2])) |
| 926 | mask |= GDB_EXCEPTION; |
| 927 | |
| 928 | if (!mask) |
| 929 | continue; |
| 930 | else |
| 931 | num_found--; |
| 932 | |
| 933 | /* Enqueue an event only if this is still a new event for |
| 934 | this fd. */ |
| 935 | |
| 936 | if (file_ptr->ready_mask == 0) |
| 937 | { |
| 938 | file_event_ptr = create_file_event (file_ptr->fd); |
| 939 | async_queue_event (file_event_ptr, TAIL); |
| 940 | } |
| 941 | file_ptr->ready_mask = mask; |
| 942 | } |
| 943 | } |
| 944 | return 0; |
| 945 | } |
| 946 | \f |
| 947 | |
| 948 | /* Create an asynchronous handler, allocating memory for it. |
| 949 | Return a pointer to the newly created handler. |
| 950 | This pointer will be used to invoke the handler by |
| 951 | invoke_async_signal_handler. |
| 952 | PROC is the function to call with CLIENT_DATA argument |
| 953 | whenever the handler is invoked. */ |
| 954 | async_signal_handler * |
| 955 | create_async_signal_handler (sig_handler_func * proc, gdb_client_data client_data) |
| 956 | { |
| 957 | async_signal_handler *async_handler_ptr; |
| 958 | |
| 959 | async_handler_ptr = |
| 960 | (async_signal_handler *) xmalloc (sizeof (async_signal_handler)); |
| 961 | async_handler_ptr->ready = 0; |
| 962 | async_handler_ptr->next_handler = NULL; |
| 963 | async_handler_ptr->proc = proc; |
| 964 | async_handler_ptr->client_data = client_data; |
| 965 | if (sighandler_list.first_handler == NULL) |
| 966 | sighandler_list.first_handler = async_handler_ptr; |
| 967 | else |
| 968 | sighandler_list.last_handler->next_handler = async_handler_ptr; |
| 969 | sighandler_list.last_handler = async_handler_ptr; |
| 970 | return async_handler_ptr; |
| 971 | } |
| 972 | |
| 973 | /* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will |
| 974 | be used when the handlers are invoked, after we have waited for |
| 975 | some event. The caller of this function is the interrupt handler |
| 976 | associated with a signal. */ |
| 977 | void |
| 978 | mark_async_signal_handler (async_signal_handler * async_handler_ptr) |
| 979 | { |
| 980 | ((async_signal_handler *) async_handler_ptr)->ready = 1; |
| 981 | async_handler_ready = 1; |
| 982 | } |
| 983 | |
| 984 | /* Call all the handlers that are ready. */ |
| 985 | static void |
| 986 | invoke_async_signal_handler (void) |
| 987 | { |
| 988 | async_signal_handler *async_handler_ptr; |
| 989 | |
| 990 | if (async_handler_ready == 0) |
| 991 | return; |
| 992 | async_handler_ready = 0; |
| 993 | |
| 994 | /* Invoke ready handlers. */ |
| 995 | |
| 996 | while (1) |
| 997 | { |
| 998 | for (async_handler_ptr = sighandler_list.first_handler; |
| 999 | async_handler_ptr != NULL; |
| 1000 | async_handler_ptr = async_handler_ptr->next_handler) |
| 1001 | { |
| 1002 | if (async_handler_ptr->ready) |
| 1003 | break; |
| 1004 | } |
| 1005 | if (async_handler_ptr == NULL) |
| 1006 | break; |
| 1007 | async_handler_ptr->ready = 0; |
| 1008 | (*async_handler_ptr->proc) (async_handler_ptr->client_data); |
| 1009 | } |
| 1010 | |
| 1011 | return; |
| 1012 | } |
| 1013 | |
| 1014 | /* Delete an asynchronous handler (ASYNC_HANDLER_PTR). |
| 1015 | Free the space allocated for it. */ |
| 1016 | void |
| 1017 | delete_async_signal_handler (async_signal_handler ** async_handler_ptr) |
| 1018 | { |
| 1019 | async_signal_handler *prev_ptr; |
| 1020 | |
| 1021 | if (sighandler_list.first_handler == (*async_handler_ptr)) |
| 1022 | { |
| 1023 | sighandler_list.first_handler = (*async_handler_ptr)->next_handler; |
| 1024 | if (sighandler_list.first_handler == NULL) |
| 1025 | sighandler_list.last_handler = NULL; |
| 1026 | } |
| 1027 | else |
| 1028 | { |
| 1029 | prev_ptr = sighandler_list.first_handler; |
| 1030 | while (prev_ptr->next_handler != (*async_handler_ptr) && prev_ptr) |
| 1031 | prev_ptr = prev_ptr->next_handler; |
| 1032 | prev_ptr->next_handler = (*async_handler_ptr)->next_handler; |
| 1033 | if (sighandler_list.last_handler == (*async_handler_ptr)) |
| 1034 | sighandler_list.last_handler = prev_ptr; |
| 1035 | } |
| 1036 | xfree ((*async_handler_ptr)); |
| 1037 | (*async_handler_ptr) = NULL; |
| 1038 | } |
| 1039 | |
| 1040 | /* Is it necessary to call invoke_async_signal_handler? */ |
| 1041 | static int |
| 1042 | check_async_ready (void) |
| 1043 | { |
| 1044 | return async_handler_ready; |
| 1045 | } |
| 1046 | |
| 1047 | /* Create a timer that will expire in MILLISECONDS from now. When the |
| 1048 | timer is ready, PROC will be executed. At creation, the timer is |
| 1049 | aded to the timers queue. This queue is kept sorted in order of |
| 1050 | increasing timers. Return a handle to the timer struct. */ |
| 1051 | int |
| 1052 | create_timer (int milliseconds, timer_handler_func * proc, gdb_client_data client_data) |
| 1053 | { |
| 1054 | struct gdb_timer *timer_ptr, *timer_index, *prev_timer; |
| 1055 | struct timeval time_now, delta; |
| 1056 | |
| 1057 | /* compute seconds */ |
| 1058 | delta.tv_sec = milliseconds / 1000; |
| 1059 | /* compute microseconds */ |
| 1060 | delta.tv_usec = (milliseconds % 1000) * 1000; |
| 1061 | |
| 1062 | gettimeofday (&time_now, NULL); |
| 1063 | |
| 1064 | timer_ptr = (struct gdb_timer *) xmalloc (sizeof (gdb_timer)); |
| 1065 | timer_ptr->when.tv_sec = time_now.tv_sec + delta.tv_sec; |
| 1066 | timer_ptr->when.tv_usec = time_now.tv_usec + delta.tv_usec; |
| 1067 | /* carry? */ |
| 1068 | if (timer_ptr->when.tv_usec >= 1000000) |
| 1069 | { |
| 1070 | timer_ptr->when.tv_sec += 1; |
| 1071 | timer_ptr->when.tv_usec -= 1000000; |
| 1072 | } |
| 1073 | timer_ptr->proc = proc; |
| 1074 | timer_ptr->client_data = client_data; |
| 1075 | timer_list.num_timers++; |
| 1076 | timer_ptr->timer_id = timer_list.num_timers; |
| 1077 | |
| 1078 | /* Now add the timer to the timer queue, making sure it is sorted in |
| 1079 | increasing order of expiration. */ |
| 1080 | |
| 1081 | for (timer_index = timer_list.first_timer; |
| 1082 | timer_index != NULL; |
| 1083 | timer_index = timer_index->next) |
| 1084 | { |
| 1085 | /* If the seconds field is greater or if it is the same, but the |
| 1086 | microsecond field is greater. */ |
| 1087 | if ((timer_index->when.tv_sec > timer_ptr->when.tv_sec) || |
| 1088 | ((timer_index->when.tv_sec == timer_ptr->when.tv_sec) |
| 1089 | && (timer_index->when.tv_usec > timer_ptr->when.tv_usec))) |
| 1090 | break; |
| 1091 | } |
| 1092 | |
| 1093 | if (timer_index == timer_list.first_timer) |
| 1094 | { |
| 1095 | timer_ptr->next = timer_list.first_timer; |
| 1096 | timer_list.first_timer = timer_ptr; |
| 1097 | |
| 1098 | } |
| 1099 | else |
| 1100 | { |
| 1101 | for (prev_timer = timer_list.first_timer; |
| 1102 | prev_timer->next != timer_index; |
| 1103 | prev_timer = prev_timer->next) |
| 1104 | ; |
| 1105 | |
| 1106 | prev_timer->next = timer_ptr; |
| 1107 | timer_ptr->next = timer_index; |
| 1108 | } |
| 1109 | |
| 1110 | gdb_notifier.timeout_valid = 0; |
| 1111 | return timer_ptr->timer_id; |
| 1112 | } |
| 1113 | |
| 1114 | /* There is a chance that the creator of the timer wants to get rid of |
| 1115 | it before it expires. */ |
| 1116 | void |
| 1117 | delete_timer (int id) |
| 1118 | { |
| 1119 | struct gdb_timer *timer_ptr, *prev_timer = NULL; |
| 1120 | |
| 1121 | /* Find the entry for the given timer. */ |
| 1122 | |
| 1123 | for (timer_ptr = timer_list.first_timer; timer_ptr != NULL; |
| 1124 | timer_ptr = timer_ptr->next) |
| 1125 | { |
| 1126 | if (timer_ptr->timer_id == id) |
| 1127 | break; |
| 1128 | } |
| 1129 | |
| 1130 | if (timer_ptr == NULL) |
| 1131 | return; |
| 1132 | /* Get rid of the timer in the timer list. */ |
| 1133 | if (timer_ptr == timer_list.first_timer) |
| 1134 | timer_list.first_timer = timer_ptr->next; |
| 1135 | else |
| 1136 | { |
| 1137 | for (prev_timer = timer_list.first_timer; |
| 1138 | prev_timer->next != timer_ptr; |
| 1139 | prev_timer = prev_timer->next) |
| 1140 | ; |
| 1141 | prev_timer->next = timer_ptr->next; |
| 1142 | } |
| 1143 | xfree (timer_ptr); |
| 1144 | |
| 1145 | gdb_notifier.timeout_valid = 0; |
| 1146 | } |
| 1147 | |
| 1148 | /* When a timer event is put on the event queue, it will be handled by |
| 1149 | this function. Just call the assiciated procedure and delete the |
| 1150 | timer event from the event queue. Repeat this for each timer that |
| 1151 | has expired. */ |
| 1152 | static void |
| 1153 | handle_timer_event (int dummy) |
| 1154 | { |
| 1155 | struct timeval time_now; |
| 1156 | struct gdb_timer *timer_ptr, *saved_timer; |
| 1157 | |
| 1158 | gettimeofday (&time_now, NULL); |
| 1159 | timer_ptr = timer_list.first_timer; |
| 1160 | |
| 1161 | while (timer_ptr != NULL) |
| 1162 | { |
| 1163 | if ((timer_ptr->when.tv_sec > time_now.tv_sec) || |
| 1164 | ((timer_ptr->when.tv_sec == time_now.tv_sec) && |
| 1165 | (timer_ptr->when.tv_usec > time_now.tv_usec))) |
| 1166 | break; |
| 1167 | |
| 1168 | /* Get rid of the timer from the beginning of the list. */ |
| 1169 | timer_list.first_timer = timer_ptr->next; |
| 1170 | saved_timer = timer_ptr; |
| 1171 | timer_ptr = timer_ptr->next; |
| 1172 | /* Call the procedure associated with that timer. */ |
| 1173 | (*saved_timer->proc) (saved_timer->client_data); |
| 1174 | xfree (saved_timer); |
| 1175 | } |
| 1176 | |
| 1177 | gdb_notifier.timeout_valid = 0; |
| 1178 | } |
| 1179 | |
| 1180 | /* Check whether any timers in the timers queue are ready. If at least |
| 1181 | one timer is ready, stick an event onto the event queue. Even in |
| 1182 | case more than one timer is ready, one event is enough, because the |
| 1183 | handle_timer_event() will go through the timers list and call the |
| 1184 | procedures associated with all that have expired. Update the |
| 1185 | timeout for the select() or poll() as well. */ |
| 1186 | static void |
| 1187 | poll_timers (void) |
| 1188 | { |
| 1189 | struct timeval time_now, delta; |
| 1190 | gdb_event *event_ptr; |
| 1191 | |
| 1192 | if (timer_list.first_timer != NULL) |
| 1193 | { |
| 1194 | gettimeofday (&time_now, NULL); |
| 1195 | delta.tv_sec = timer_list.first_timer->when.tv_sec - time_now.tv_sec; |
| 1196 | delta.tv_usec = timer_list.first_timer->when.tv_usec - time_now.tv_usec; |
| 1197 | /* borrow? */ |
| 1198 | if (delta.tv_usec < 0) |
| 1199 | { |
| 1200 | delta.tv_sec -= 1; |
| 1201 | delta.tv_usec += 1000000; |
| 1202 | } |
| 1203 | |
| 1204 | /* Oops it expired already. Tell select / poll to return |
| 1205 | immediately. (Cannot simply test if delta.tv_sec is negative |
| 1206 | because time_t might be unsigned.) */ |
| 1207 | if (timer_list.first_timer->when.tv_sec < time_now.tv_sec |
| 1208 | || (timer_list.first_timer->when.tv_sec == time_now.tv_sec |
| 1209 | && timer_list.first_timer->when.tv_usec < time_now.tv_usec)) |
| 1210 | { |
| 1211 | delta.tv_sec = 0; |
| 1212 | delta.tv_usec = 0; |
| 1213 | } |
| 1214 | |
| 1215 | if (delta.tv_sec == 0 && delta.tv_usec == 0) |
| 1216 | { |
| 1217 | event_ptr = (gdb_event *) xmalloc (sizeof (gdb_event)); |
| 1218 | event_ptr->proc = handle_timer_event; |
| 1219 | event_ptr->fd = timer_list.first_timer->timer_id; |
| 1220 | async_queue_event (event_ptr, TAIL); |
| 1221 | } |
| 1222 | |
| 1223 | /* Now we need to update the timeout for select/ poll, because we |
| 1224 | don't want to sit there while this timer is expiring. */ |
| 1225 | if (use_poll) |
| 1226 | { |
| 1227 | #ifdef HAVE_POLL |
| 1228 | gdb_notifier.poll_timeout = delta.tv_sec * 1000; |
| 1229 | #else |
| 1230 | internal_error (__FILE__, __LINE__, |
| 1231 | _("use_poll without HAVE_POLL")); |
| 1232 | #endif /* HAVE_POLL */ |
| 1233 | } |
| 1234 | else |
| 1235 | { |
| 1236 | gdb_notifier.select_timeout.tv_sec = delta.tv_sec; |
| 1237 | gdb_notifier.select_timeout.tv_usec = delta.tv_usec; |
| 1238 | } |
| 1239 | gdb_notifier.timeout_valid = 1; |
| 1240 | } |
| 1241 | else |
| 1242 | gdb_notifier.timeout_valid = 0; |
| 1243 | } |