1 /* Event loop machinery for GDB, the GNU debugger.
2 Copyright 1999, 2000, 2001 Free Software Foundation, Inc.
3 Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions.
5 This file is part of GDB.
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.
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.
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. */
23 #include "event-loop.h"
24 #include "event-top.h"
27 #if defined (HAVE_POLL_H)
29 #elif defined (HAVE_SYS_POLL_H)
34 #include <sys/types.h>
35 #include "gdb_string.h"
39 typedef struct gdb_event gdb_event
;
40 typedef void (event_handler_func
) (int);
42 /* Event for the GDB event system. Events are queued by calling
43 async_queue_event and serviced later on by gdb_do_one_event. An
44 event can be, for instance, a file descriptor becoming ready to be
45 read. Servicing an event simply means that the procedure PROC will
46 be called. We have 2 queues, one for file handlers that we listen
47 to in the event loop, and one for the file handlers+events that are
48 ready. The procedure PROC associated with each event is always the
49 same (handle_file_event). Its duty is to invoke the handler
50 associated with the file descriptor whose state change generated
51 the event, plus doing other cleanups and such. */
55 event_handler_func
*proc
; /* Procedure to call to service this event. */
56 int fd
; /* File descriptor that is ready. */
57 struct gdb_event
*next_event
; /* Next in list of events or NULL. */
60 /* Information about each file descriptor we register with the event
63 typedef struct file_handler
65 int fd
; /* File descriptor. */
66 int mask
; /* Events we want to monitor: POLLIN, etc. */
67 int ready_mask
; /* Events that have been seen since
69 handler_func
*proc
; /* Procedure to call when fd is ready. */
70 gdb_client_data client_data
; /* Argument to pass to proc. */
71 int error
; /* Was an error detected on this fd? */
72 struct file_handler
*next_file
; /* Next registered file descriptor. */
76 /* PROC is a function to be invoked when the READY flag is set. This
77 happens when there has been a signal and the corresponding signal
78 handler has 'triggered' this async_signal_handler for
79 execution. The actual work to be done in response to a signal will
80 be carried out by PROC at a later time, within process_event. This
81 provides a deferred execution of signal handlers.
82 Async_init_signals takes care of setting up such an
83 asyn_signal_handler for each interesting signal. */
84 typedef struct async_signal_handler
86 int ready
; /* If ready, call this handler from the main event loop,
87 using invoke_async_handler. */
88 struct async_signal_handler
*next_handler
; /* Ptr to next handler */
89 sig_handler_func
*proc
; /* Function to call to do the work */
90 gdb_client_data client_data
; /* Argument to async_handler_func */
96 - the first event in the queue is the head of the queue.
97 It will be the next to be serviced.
98 - the last event in the queue
100 Events can be inserted at the front of the queue or at the end of
101 the queue. Events will be extracted from the queue for processing
102 starting from the head. Therefore, events inserted at the head of
103 the queue will be processed in a last in first out fashion, while
104 those inserted at the tail of the queue will be processed in a first
105 in first out manner. All the fields are NULL if the queue is
110 gdb_event
*first_event
; /* First pending event */
111 gdb_event
*last_event
; /* Last pending event */
115 /* Gdb_notifier is just a list of file descriptors gdb is interested in.
116 These are the input file descriptor, and the target file
117 descriptor. We have two flavors of the notifier, one for platforms
118 that have the POLL function, the other for those that don't, and
119 only support SELECT. Each of the elements in the gdb_notifier list is
120 basically a description of what kind of events gdb is interested
123 /* As of 1999-04-30 only the input file descriptor is registered with the
126 /* Do we use poll or select ? */
131 #endif /* HAVE_POLL */
133 static unsigned char use_poll
= USE_POLL
;
137 /* Ptr to head of file handler list. */
138 file_handler
*first_file_handler
;
141 /* Ptr to array of pollfd structures. */
142 struct pollfd
*poll_fds
;
144 /* Timeout in milliseconds for calls to poll(). */
148 /* Masks to be used in the next call to select.
149 Bits are set in response to calls to create_file_handler. */
150 fd_set check_masks
[3];
152 /* What file descriptors were found ready by select. */
153 fd_set ready_masks
[3];
155 /* Number of file descriptors to monitor. (for poll) */
156 /* Number of valid bits (highest fd value + 1). (for select) */
159 /* Time structure for calls to select(). */
160 struct timeval select_timeout
;
162 /* Flag to tell whether the timeout should be used. */
167 /* Structure associated with a timer. PROC will be executed at the
168 first occasion after WHEN. */
173 struct gdb_timer
*next
;
174 timer_handler_func
*proc
; /* Function to call to do the work */
175 gdb_client_data client_data
; /* Argument to async_handler_func */
179 /* List of currently active timers. It is sorted in order of
180 increasing timers. */
183 /* Pointer to first in timer list. */
184 struct gdb_timer
*first_timer
;
186 /* Id of the last timer created. */
191 /* All the async_signal_handlers gdb is interested in are kept onto
195 /* Pointer to first in handler list. */
196 async_signal_handler
*first_handler
;
198 /* Pointer to last in handler list. */
199 async_signal_handler
*last_handler
;
203 /* Are any of the handlers ready? Check this variable using
204 check_async_ready. This is used by process_event, to determine
205 whether or not to invoke the invoke_async_signal_handler
207 static int async_handler_ready
= 0;
209 static void create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
);
210 static void invoke_async_signal_handler (void);
211 static void handle_file_event (int event_file_desc
);
212 static int gdb_wait_for_event (void);
213 static int gdb_do_one_event (void *data
);
214 static int check_async_ready (void);
215 static void async_queue_event (gdb_event
* event_ptr
, queue_position position
);
216 static gdb_event
*create_file_event (int fd
);
217 static int process_event (void);
218 static void handle_timer_event (int dummy
);
219 static void poll_timers (void);
222 /* Insert an event object into the gdb event queue at
223 the specified position.
224 POSITION can be head or tail, with values TAIL, HEAD.
225 EVENT_PTR points to the event to be inserted into the queue.
226 The caller must allocate memory for the event. It is freed
227 after the event has ben handled.
228 Events in the queue will be processed head to tail, therefore,
229 events inserted at the head of the queue will be processed
230 as last in first out. Event appended at the tail of the queue
231 will be processed first in first out. */
233 async_queue_event (gdb_event
* event_ptr
, queue_position position
)
235 if (position
== TAIL
)
237 /* The event will become the new last_event. */
239 event_ptr
->next_event
= NULL
;
240 if (event_queue
.first_event
== NULL
)
241 event_queue
.first_event
= event_ptr
;
243 event_queue
.last_event
->next_event
= event_ptr
;
244 event_queue
.last_event
= event_ptr
;
246 else if (position
== HEAD
)
248 /* The event becomes the new first_event. */
250 event_ptr
->next_event
= event_queue
.first_event
;
251 if (event_queue
.first_event
== NULL
)
252 event_queue
.last_event
= event_ptr
;
253 event_queue
.first_event
= event_ptr
;
257 /* Create a file event, to be enqueued in the event queue for
258 processing. The procedure associated to this event is always
259 handle_file_event, which will in turn invoke the one that was
260 associated to FD when it was registered with the event loop. */
262 create_file_event (int fd
)
264 gdb_event
*file_event_ptr
;
266 file_event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
267 file_event_ptr
->proc
= handle_file_event
;
268 file_event_ptr
->fd
= fd
;
269 return (file_event_ptr
);
272 /* Process one event.
273 The event can be the next one to be serviced in the event queue,
274 or an asynchronous event handler can be invoked in response to
275 the reception of a signal.
276 If an event was processed (either way), 1 is returned otherwise
278 Scan the queue from head to tail, processing therefore the high
279 priority events first, by invoking the associated event handler
284 gdb_event
*event_ptr
, *prev_ptr
;
285 event_handler_func
*proc
;
288 /* First let's see if there are any asynchronous event handlers that
289 are ready. These would be the result of invoking any of the
292 if (check_async_ready ())
294 invoke_async_signal_handler ();
298 /* Look in the event queue to find an event that is ready
301 for (event_ptr
= event_queue
.first_event
; event_ptr
!= NULL
;
302 event_ptr
= event_ptr
->next_event
)
304 /* Call the handler for the event. */
306 proc
= event_ptr
->proc
;
309 /* Let's get rid of the event from the event queue. We need to
310 do this now because while processing the event, the proc
311 function could end up calling 'error' and therefore jump out
312 to the caller of this function, gdb_do_one_event. In that
313 case, we would have on the event queue an event wich has been
314 processed, but not deleted. */
316 if (event_queue
.first_event
== event_ptr
)
318 event_queue
.first_event
= event_ptr
->next_event
;
319 if (event_ptr
->next_event
== NULL
)
320 event_queue
.last_event
= NULL
;
324 prev_ptr
= event_queue
.first_event
;
325 while (prev_ptr
->next_event
!= event_ptr
)
326 prev_ptr
= prev_ptr
->next_event
;
328 prev_ptr
->next_event
= event_ptr
->next_event
;
329 if (event_ptr
->next_event
== NULL
)
330 event_queue
.last_event
= prev_ptr
;
334 /* Now call the procedure associated with the event. */
339 /* this is the case if there are no event on the event queue. */
343 /* Process one high level event. If nothing is ready at this time,
344 wait for something to happen (via gdb_wait_for_event), then process
345 it. Returns >0 if something was done otherwise returns <0 (this
346 can happen if there are no event sources to wait for). If an error
347 occurs catch_errors() which calls this function returns zero. */
350 gdb_do_one_event (void *data
)
352 /* Any events already waiting in the queue? */
353 if (process_event ())
358 /* Are any timers that are ready? If so, put an event on the queue. */
361 /* Wait for a new event. If gdb_wait_for_event returns -1,
362 we should get out because this means that there are no
363 event sources left. This will make the event loop stop,
364 and the application exit. */
366 if (gdb_wait_for_event () < 0)
371 /* Handle any new events occurred while waiting. */
372 if (process_event ())
377 /* If gdb_wait_for_event has returned 1, it means that one
378 event has been handled. We break out of the loop. */
382 /* Start up the event loop. This is the entry point to the event loop
383 from the command loop. */
386 start_event_loop (void)
388 /* Loop until there is nothing to do. This is the entry point to the
389 event loop engine. gdb_do_one_event, called via catch_errors()
390 will process one event for each invocation. It blocks waits for
391 an event and then processes it. >0 when an event is processed, 0
392 when catch_errors() caught an error and <0 when there are no
393 longer any event sources registered. */
396 int result
= catch_errors (gdb_do_one_event
, 0, "", RETURN_MASK_ALL
);
401 /* FIXME: this should really be a call to a hook that is
402 interface specific, because interfaces can display the
403 prompt in their own way. */
404 display_gdb_prompt (0);
405 /* This call looks bizarre, but it is required. If the user
406 entered a command that caused an error,
407 after_char_processing_hook won't be called from
408 rl_callback_read_char_wrapper. Using a cleanup there
409 won't work, since we want this function to be called
410 after a new prompt is printed. */
411 if (after_char_processing_hook
)
412 (*after_char_processing_hook
) ();
413 /* Maybe better to set a flag to be checked somewhere as to
414 whether display the prompt or not. */
418 /* We are done with the event loop. There are no more event sources
419 to listen to. So we exit GDB. */
424 /* Wrapper function for create_file_handler, so that the caller
425 doesn't have to know implementation details about the use of poll
428 add_file_handler (int fd
, handler_func
* proc
, gdb_client_data client_data
)
437 /* Check to see if poll () is usable. If not, we'll switch to
438 use select. This can happen on systems like
439 m68k-motorola-sys, `poll' cannot be used to wait for `stdin'.
440 On m68k-motorola-sysv, tty's are not stream-based and not
444 if (poll (&fds
, 1, 0) == 1 && (fds
.revents
& POLLNVAL
))
447 internal_error (__FILE__
, __LINE__
,
448 "use_poll without HAVE_POLL");
449 #endif /* HAVE_POLL */
454 create_file_handler (fd
, POLLIN
, proc
, client_data
);
456 internal_error (__FILE__
, __LINE__
,
457 "use_poll without HAVE_POLL");
461 create_file_handler (fd
, GDB_READABLE
| GDB_EXCEPTION
, proc
, client_data
);
464 /* Add a file handler/descriptor to the list of descriptors we are
466 FD is the file descriptor for the file/stream to be listened to.
467 For the poll case, MASK is a combination (OR) of
468 POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM,
469 POLLWRBAND: these are the events we are interested in. If any of them
470 occurs, proc should be called.
471 For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION.
472 PROC is the procedure that will be called when an event occurs for
473 FD. CLIENT_DATA is the argument to pass to PROC. */
475 create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
)
477 file_handler
*file_ptr
;
479 /* Do we already have a file handler for this file? (We may be
480 changing its associated procedure). */
481 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
482 file_ptr
= file_ptr
->next_file
)
484 if (file_ptr
->fd
== fd
)
488 /* It is a new file descriptor. Add it to the list. Otherwise, just
489 change the data associated with it. */
490 if (file_ptr
== NULL
)
492 file_ptr
= (file_handler
*) xmalloc (sizeof (file_handler
));
494 file_ptr
->ready_mask
= 0;
495 file_ptr
->next_file
= gdb_notifier
.first_file_handler
;
496 gdb_notifier
.first_file_handler
= file_ptr
;
501 gdb_notifier
.num_fds
++;
502 if (gdb_notifier
.poll_fds
)
503 gdb_notifier
.poll_fds
=
504 (struct pollfd
*) xrealloc (gdb_notifier
.poll_fds
,
505 (gdb_notifier
.num_fds
506 * sizeof (struct pollfd
)));
508 gdb_notifier
.poll_fds
=
509 (struct pollfd
*) xmalloc (sizeof (struct pollfd
));
510 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->fd
= fd
;
511 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->events
= mask
;
512 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->revents
= 0;
514 internal_error (__FILE__
, __LINE__
,
515 "use_poll without HAVE_POLL");
516 #endif /* HAVE_POLL */
520 if (mask
& GDB_READABLE
)
521 FD_SET (fd
, &gdb_notifier
.check_masks
[0]);
523 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
525 if (mask
& GDB_WRITABLE
)
526 FD_SET (fd
, &gdb_notifier
.check_masks
[1]);
528 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
530 if (mask
& GDB_EXCEPTION
)
531 FD_SET (fd
, &gdb_notifier
.check_masks
[2]);
533 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
535 if (gdb_notifier
.num_fds
<= fd
)
536 gdb_notifier
.num_fds
= fd
+ 1;
540 file_ptr
->proc
= proc
;
541 file_ptr
->client_data
= client_data
;
542 file_ptr
->mask
= mask
;
545 /* Remove the file descriptor FD from the list of monitored fd's:
546 i.e. we don't care anymore about events on the FD. */
548 delete_file_handler (int fd
)
550 file_handler
*file_ptr
, *prev_ptr
= NULL
;
554 struct pollfd
*new_poll_fds
;
557 /* Find the entry for the given file. */
559 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
560 file_ptr
= file_ptr
->next_file
)
562 if (file_ptr
->fd
== fd
)
566 if (file_ptr
== NULL
)
572 /* Create a new poll_fds array by copying every fd's information but the
573 one we want to get rid of. */
576 (struct pollfd
*) xmalloc ((gdb_notifier
.num_fds
- 1) * sizeof (struct pollfd
));
578 for (i
= 0, j
= 0; i
< gdb_notifier
.num_fds
; i
++)
580 if ((gdb_notifier
.poll_fds
+ i
)->fd
!= fd
)
582 (new_poll_fds
+ j
)->fd
= (gdb_notifier
.poll_fds
+ i
)->fd
;
583 (new_poll_fds
+ j
)->events
= (gdb_notifier
.poll_fds
+ i
)->events
;
584 (new_poll_fds
+ j
)->revents
= (gdb_notifier
.poll_fds
+ i
)->revents
;
588 xfree (gdb_notifier
.poll_fds
);
589 gdb_notifier
.poll_fds
= new_poll_fds
;
590 gdb_notifier
.num_fds
--;
592 internal_error (__FILE__
, __LINE__
,
593 "use_poll without HAVE_POLL");
594 #endif /* HAVE_POLL */
598 if (file_ptr
->mask
& GDB_READABLE
)
599 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
600 if (file_ptr
->mask
& GDB_WRITABLE
)
601 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
602 if (file_ptr
->mask
& GDB_EXCEPTION
)
603 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
605 /* Find current max fd. */
607 if ((fd
+ 1) == gdb_notifier
.num_fds
)
609 gdb_notifier
.num_fds
--;
610 for (i
= gdb_notifier
.num_fds
; i
; i
--)
612 if (FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[0])
613 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[1])
614 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[2]))
617 gdb_notifier
.num_fds
= i
;
621 /* Deactivate the file descriptor, by clearing its mask,
622 so that it will not fire again. */
626 /* Get rid of the file handler in the file handler list. */
627 if (file_ptr
== gdb_notifier
.first_file_handler
)
628 gdb_notifier
.first_file_handler
= file_ptr
->next_file
;
631 for (prev_ptr
= gdb_notifier
.first_file_handler
;
632 prev_ptr
->next_file
!= file_ptr
;
633 prev_ptr
= prev_ptr
->next_file
)
635 prev_ptr
->next_file
= file_ptr
->next_file
;
640 /* Handle the given event by calling the procedure associated to the
641 corresponding file handler. Called by process_event indirectly,
642 through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the
643 event in the front of the event queue. */
645 handle_file_event (int event_file_desc
)
647 file_handler
*file_ptr
;
651 int error_mask_returned
;
654 /* Search the file handler list to find one that matches the fd in
656 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
657 file_ptr
= file_ptr
->next_file
)
659 if (file_ptr
->fd
== event_file_desc
)
661 /* With poll, the ready_mask could have any of three events
662 set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot
663 be used in the requested event mask (events), but they
664 can be returned in the return mask (revents). We need to
665 check for those event too, and add them to the mask which
666 will be passed to the handler. */
668 /* See if the desired events (mask) match the received
669 events (ready_mask). */
674 error_mask
= POLLHUP
| POLLERR
| POLLNVAL
;
675 mask
= (file_ptr
->ready_mask
& file_ptr
->mask
) |
676 (file_ptr
->ready_mask
& error_mask
);
677 error_mask_returned
= mask
& error_mask
;
679 if (error_mask_returned
!= 0)
681 /* Work in progress. We may need to tell somebody what
682 kind of error we had. */
683 if (error_mask_returned
& POLLHUP
)
684 printf_unfiltered ("Hangup detected on fd %d\n", file_ptr
->fd
);
685 if (error_mask_returned
& POLLERR
)
686 printf_unfiltered ("Error detected on fd %d\n", file_ptr
->fd
);
687 if (error_mask_returned
& POLLNVAL
)
688 printf_unfiltered ("Invalid or non-`poll'able fd %d\n", file_ptr
->fd
);
694 internal_error (__FILE__
, __LINE__
,
695 "use_poll without HAVE_POLL");
696 #endif /* HAVE_POLL */
700 if (file_ptr
->ready_mask
& GDB_EXCEPTION
)
702 printf_unfiltered ("Exception condition detected on fd %d\n", file_ptr
->fd
);
707 mask
= file_ptr
->ready_mask
& file_ptr
->mask
;
710 /* Clear the received events for next time around. */
711 file_ptr
->ready_mask
= 0;
713 /* If there was a match, then call the handler. */
715 (*file_ptr
->proc
) (file_ptr
->error
, file_ptr
->client_data
);
721 /* Called by gdb_do_one_event to wait for new events on the
722 monitored file descriptors. Queue file events as they are
723 detected by the poll.
724 If there are no events, this function will block in the
726 Return -1 if there are no files descriptors to monitor,
727 otherwise return 0. */
729 gdb_wait_for_event (void)
731 file_handler
*file_ptr
;
732 gdb_event
*file_event_ptr
;
736 /* Make sure all output is done before getting another event. */
737 gdb_flush (gdb_stdout
);
738 gdb_flush (gdb_stderr
);
740 if (gdb_notifier
.num_fds
== 0)
747 poll (gdb_notifier
.poll_fds
,
748 (unsigned long) gdb_notifier
.num_fds
,
749 gdb_notifier
.timeout_valid
? gdb_notifier
.poll_timeout
: -1);
751 /* Don't print anything if we get out of poll because of a
753 if (num_found
== -1 && errno
!= EINTR
)
754 perror_with_name ("Poll");
756 internal_error (__FILE__
, __LINE__
,
757 "use_poll without HAVE_POLL");
758 #endif /* HAVE_POLL */
762 gdb_notifier
.ready_masks
[0] = gdb_notifier
.check_masks
[0];
763 gdb_notifier
.ready_masks
[1] = gdb_notifier
.check_masks
[1];
764 gdb_notifier
.ready_masks
[2] = gdb_notifier
.check_masks
[2];
765 num_found
= select (gdb_notifier
.num_fds
,
766 &gdb_notifier
.ready_masks
[0],
767 &gdb_notifier
.ready_masks
[1],
768 &gdb_notifier
.ready_masks
[2],
769 gdb_notifier
.timeout_valid
770 ? &gdb_notifier
.select_timeout
: NULL
);
772 /* Clear the masks after an error from select. */
775 FD_ZERO (&gdb_notifier
.ready_masks
[0]);
776 FD_ZERO (&gdb_notifier
.ready_masks
[1]);
777 FD_ZERO (&gdb_notifier
.ready_masks
[2]);
778 /* Dont print anything is we got a signal, let gdb handle it. */
780 perror_with_name ("Select");
784 /* Enqueue all detected file events. */
789 for (i
= 0; (i
< gdb_notifier
.num_fds
) && (num_found
> 0); i
++)
791 if ((gdb_notifier
.poll_fds
+ i
)->revents
)
796 for (file_ptr
= gdb_notifier
.first_file_handler
;
798 file_ptr
= file_ptr
->next_file
)
800 if (file_ptr
->fd
== (gdb_notifier
.poll_fds
+ i
)->fd
)
806 /* Enqueue an event only if this is still a new event for
808 if (file_ptr
->ready_mask
== 0)
810 file_event_ptr
= create_file_event (file_ptr
->fd
);
811 async_queue_event (file_event_ptr
, TAIL
);
815 file_ptr
->ready_mask
= (gdb_notifier
.poll_fds
+ i
)->revents
;
818 internal_error (__FILE__
, __LINE__
,
819 "use_poll without HAVE_POLL");
820 #endif /* HAVE_POLL */
824 for (file_ptr
= gdb_notifier
.first_file_handler
;
825 (file_ptr
!= NULL
) && (num_found
> 0);
826 file_ptr
= file_ptr
->next_file
)
830 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[0]))
831 mask
|= GDB_READABLE
;
832 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[1]))
833 mask
|= GDB_WRITABLE
;
834 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[2]))
835 mask
|= GDB_EXCEPTION
;
842 /* Enqueue an event only if this is still a new event for
845 if (file_ptr
->ready_mask
== 0)
847 file_event_ptr
= create_file_event (file_ptr
->fd
);
848 async_queue_event (file_event_ptr
, TAIL
);
850 file_ptr
->ready_mask
= mask
;
857 /* Create an asynchronous handler, allocating memory for it.
858 Return a pointer to the newly created handler.
859 This pointer will be used to invoke the handler by
860 invoke_async_signal_handler.
861 PROC is the function to call with CLIENT_DATA argument
862 whenever the handler is invoked. */
863 async_signal_handler
*
864 create_async_signal_handler (sig_handler_func
* proc
, gdb_client_data client_data
)
866 async_signal_handler
*async_handler_ptr
;
869 (async_signal_handler
*) xmalloc (sizeof (async_signal_handler
));
870 async_handler_ptr
->ready
= 0;
871 async_handler_ptr
->next_handler
= NULL
;
872 async_handler_ptr
->proc
= proc
;
873 async_handler_ptr
->client_data
= client_data
;
874 if (sighandler_list
.first_handler
== NULL
)
875 sighandler_list
.first_handler
= async_handler_ptr
;
877 sighandler_list
.last_handler
->next_handler
= async_handler_ptr
;
878 sighandler_list
.last_handler
= async_handler_ptr
;
879 return async_handler_ptr
;
882 /* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will
883 be used when the handlers are invoked, after we have waited for
884 some event. The caller of this function is the interrupt handler
885 associated with a signal. */
887 mark_async_signal_handler (async_signal_handler
* async_handler_ptr
)
889 ((async_signal_handler
*) async_handler_ptr
)->ready
= 1;
890 async_handler_ready
= 1;
893 /* Call all the handlers that are ready. */
895 invoke_async_signal_handler (void)
897 async_signal_handler
*async_handler_ptr
;
899 if (async_handler_ready
== 0)
901 async_handler_ready
= 0;
903 /* Invoke ready handlers. */
907 for (async_handler_ptr
= sighandler_list
.first_handler
;
908 async_handler_ptr
!= NULL
;
909 async_handler_ptr
= async_handler_ptr
->next_handler
)
911 if (async_handler_ptr
->ready
)
914 if (async_handler_ptr
== NULL
)
916 async_handler_ptr
->ready
= 0;
917 (*async_handler_ptr
->proc
) (async_handler_ptr
->client_data
);
923 /* Delete an asynchronous handler (ASYNC_HANDLER_PTR).
924 Free the space allocated for it. */
926 delete_async_signal_handler (async_signal_handler
** async_handler_ptr
)
928 async_signal_handler
*prev_ptr
;
930 if (sighandler_list
.first_handler
== (*async_handler_ptr
))
932 sighandler_list
.first_handler
= (*async_handler_ptr
)->next_handler
;
933 if (sighandler_list
.first_handler
== NULL
)
934 sighandler_list
.last_handler
= NULL
;
938 prev_ptr
= sighandler_list
.first_handler
;
939 while (prev_ptr
->next_handler
!= (*async_handler_ptr
) && prev_ptr
)
940 prev_ptr
= prev_ptr
->next_handler
;
941 prev_ptr
->next_handler
= (*async_handler_ptr
)->next_handler
;
942 if (sighandler_list
.last_handler
== (*async_handler_ptr
))
943 sighandler_list
.last_handler
= prev_ptr
;
945 xfree ((*async_handler_ptr
));
946 (*async_handler_ptr
) = NULL
;
949 /* Is it necessary to call invoke_async_signal_handler? */
951 check_async_ready (void)
953 return async_handler_ready
;
956 /* Create a timer that will expire in MILLISECONDS from now. When the
957 timer is ready, PROC will be executed. At creation, the timer is
958 aded to the timers queue. This queue is kept sorted in order of
959 increasing timers. Return a handle to the timer struct. */
961 create_timer (int milliseconds
, timer_handler_func
* proc
, gdb_client_data client_data
)
963 struct gdb_timer
*timer_ptr
, *timer_index
, *prev_timer
;
964 struct timeval time_now
, delta
;
966 /* compute seconds */
967 delta
.tv_sec
= milliseconds
/ 1000;
968 /* compute microseconds */
969 delta
.tv_usec
= (milliseconds
% 1000) * 1000;
971 gettimeofday (&time_now
, NULL
);
973 timer_ptr
= (struct gdb_timer
*) xmalloc (sizeof (gdb_timer
));
974 timer_ptr
->when
.tv_sec
= time_now
.tv_sec
+ delta
.tv_sec
;
975 timer_ptr
->when
.tv_usec
= time_now
.tv_usec
+ delta
.tv_usec
;
977 if (timer_ptr
->when
.tv_usec
>= 1000000)
979 timer_ptr
->when
.tv_sec
+= 1;
980 timer_ptr
->when
.tv_usec
-= 1000000;
982 timer_ptr
->proc
= proc
;
983 timer_ptr
->client_data
= client_data
;
984 timer_list
.num_timers
++;
985 timer_ptr
->timer_id
= timer_list
.num_timers
;
987 /* Now add the timer to the timer queue, making sure it is sorted in
988 increasing order of expiration. */
990 for (timer_index
= timer_list
.first_timer
;
992 timer_index
= timer_index
->next
)
994 /* If the seconds field is greater or if it is the same, but the
995 microsecond field is greater. */
996 if ((timer_index
->when
.tv_sec
> timer_ptr
->when
.tv_sec
) ||
997 ((timer_index
->when
.tv_sec
== timer_ptr
->when
.tv_sec
)
998 && (timer_index
->when
.tv_usec
> timer_ptr
->when
.tv_usec
)))
1002 if (timer_index
== timer_list
.first_timer
)
1004 timer_ptr
->next
= timer_list
.first_timer
;
1005 timer_list
.first_timer
= timer_ptr
;
1010 for (prev_timer
= timer_list
.first_timer
;
1011 prev_timer
->next
!= timer_index
;
1012 prev_timer
= prev_timer
->next
)
1015 prev_timer
->next
= timer_ptr
;
1016 timer_ptr
->next
= timer_index
;
1019 gdb_notifier
.timeout_valid
= 0;
1020 return timer_ptr
->timer_id
;
1023 /* There is a chance that the creator of the timer wants to get rid of
1024 it before it expires. */
1026 delete_timer (int id
)
1028 struct gdb_timer
*timer_ptr
, *prev_timer
= NULL
;
1030 /* Find the entry for the given timer. */
1032 for (timer_ptr
= timer_list
.first_timer
; timer_ptr
!= NULL
;
1033 timer_ptr
= timer_ptr
->next
)
1035 if (timer_ptr
->timer_id
== id
)
1039 if (timer_ptr
== NULL
)
1041 /* Get rid of the timer in the timer list. */
1042 if (timer_ptr
== timer_list
.first_timer
)
1043 timer_list
.first_timer
= timer_ptr
->next
;
1046 for (prev_timer
= timer_list
.first_timer
;
1047 prev_timer
->next
!= timer_ptr
;
1048 prev_timer
= prev_timer
->next
)
1050 prev_timer
->next
= timer_ptr
->next
;
1054 gdb_notifier
.timeout_valid
= 0;
1057 /* When a timer event is put on the event queue, it will be handled by
1058 this function. Just call the assiciated procedure and delete the
1059 timer event from the event queue. Repeat this for each timer that
1062 handle_timer_event (int dummy
)
1064 struct timeval time_now
;
1065 struct gdb_timer
*timer_ptr
, *saved_timer
;
1067 gettimeofday (&time_now
, NULL
);
1068 timer_ptr
= timer_list
.first_timer
;
1070 while (timer_ptr
!= NULL
)
1072 if ((timer_ptr
->when
.tv_sec
> time_now
.tv_sec
) ||
1073 ((timer_ptr
->when
.tv_sec
== time_now
.tv_sec
) &&
1074 (timer_ptr
->when
.tv_usec
> time_now
.tv_usec
)))
1077 /* Get rid of the timer from the beginning of the list. */
1078 timer_list
.first_timer
= timer_ptr
->next
;
1079 saved_timer
= timer_ptr
;
1080 timer_ptr
= timer_ptr
->next
;
1081 /* Call the procedure associated with that timer. */
1082 (*saved_timer
->proc
) (saved_timer
->client_data
);
1083 xfree (saved_timer
);
1086 gdb_notifier
.timeout_valid
= 0;
1089 /* Check whether any timers in the timers queue are ready. If at least
1090 one timer is ready, stick an event onto the event queue. Even in
1091 case more than one timer is ready, one event is enough, because the
1092 handle_timer_event() will go through the timers list and call the
1093 procedures associated with all that have expired. Update the
1094 timeout for the select() or poll() as well. */
1098 struct timeval time_now
, delta
;
1099 gdb_event
*event_ptr
;
1101 if (timer_list
.first_timer
!= NULL
)
1103 gettimeofday (&time_now
, NULL
);
1104 delta
.tv_sec
= timer_list
.first_timer
->when
.tv_sec
- time_now
.tv_sec
;
1105 delta
.tv_usec
= timer_list
.first_timer
->when
.tv_usec
- time_now
.tv_usec
;
1107 if (delta
.tv_usec
< 0)
1110 delta
.tv_usec
+= 1000000;
1113 /* Oops it expired already. Tell select / poll to return
1114 immediately. (Cannot simply test if delta.tv_sec is negative
1115 because time_t might be unsigned.) */
1116 if (timer_list
.first_timer
->when
.tv_sec
< time_now
.tv_sec
1117 || (timer_list
.first_timer
->when
.tv_sec
== time_now
.tv_sec
1118 && timer_list
.first_timer
->when
.tv_usec
< time_now
.tv_usec
))
1124 if (delta
.tv_sec
== 0 && delta
.tv_usec
== 0)
1126 event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
1127 event_ptr
->proc
= handle_timer_event
;
1128 event_ptr
->fd
= timer_list
.first_timer
->timer_id
;
1129 async_queue_event (event_ptr
, TAIL
);
1132 /* Now we need to update the timeout for select/ poll, because we
1133 don't want to sit there while this timer is expiring. */
1137 gdb_notifier
.poll_timeout
= delta
.tv_sec
* 1000;
1139 internal_error (__FILE__
, __LINE__
,
1140 "use_poll without HAVE_POLL");
1141 #endif /* HAVE_POLL */
1145 gdb_notifier
.select_timeout
.tv_sec
= delta
.tv_sec
;
1146 gdb_notifier
.select_timeout
.tv_usec
= delta
.tv_usec
;
1148 gdb_notifier
.timeout_valid
= 1;
1151 gdb_notifier
.timeout_valid
= 0;