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 /* Maybe better to set a flag to be checked somewhere as to
406 whether display the prompt or not. */
410 /* We are done with the event loop. There are no more event sources
411 to listen to. So we exit GDB. */
416 /* Wrapper function for create_file_handler, so that the caller
417 doesn't have to know implementation details about the use of poll
420 add_file_handler (int fd
, handler_func
* proc
, gdb_client_data client_data
)
429 /* Check to see if poll () is usable. If not, we'll switch to
430 use select. This can happen on systems like
431 m68k-motorola-sys, `poll' cannot be used to wait for `stdin'.
432 On m68k-motorola-sysv, tty's are not stream-based and not
436 if (poll (&fds
, 1, 0) == 1 && (fds
.revents
& POLLNVAL
))
439 internal_error (__FILE__
, __LINE__
,
440 "use_poll without HAVE_POLL");
441 #endif /* HAVE_POLL */
446 create_file_handler (fd
, POLLIN
, proc
, client_data
);
448 internal_error (__FILE__
, __LINE__
,
449 "use_poll without HAVE_POLL");
453 create_file_handler (fd
, GDB_READABLE
| GDB_EXCEPTION
, proc
, client_data
);
456 /* Add a file handler/descriptor to the list of descriptors we are
458 FD is the file descriptor for the file/stream to be listened to.
459 For the poll case, MASK is a combination (OR) of
460 POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM,
461 POLLWRBAND: these are the events we are interested in. If any of them
462 occurs, proc should be called.
463 For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION.
464 PROC is the procedure that will be called when an event occurs for
465 FD. CLIENT_DATA is the argument to pass to PROC. */
467 create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
)
469 file_handler
*file_ptr
;
471 /* Do we already have a file handler for this file? (We may be
472 changing its associated procedure). */
473 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
474 file_ptr
= file_ptr
->next_file
)
476 if (file_ptr
->fd
== fd
)
480 /* It is a new file descriptor. Add it to the list. Otherwise, just
481 change the data associated with it. */
482 if (file_ptr
== NULL
)
484 file_ptr
= (file_handler
*) xmalloc (sizeof (file_handler
));
486 file_ptr
->ready_mask
= 0;
487 file_ptr
->next_file
= gdb_notifier
.first_file_handler
;
488 gdb_notifier
.first_file_handler
= file_ptr
;
490 file_ptr
->proc
= proc
;
491 file_ptr
->client_data
= client_data
;
492 file_ptr
->mask
= mask
;
497 gdb_notifier
.num_fds
++;
498 if (gdb_notifier
.poll_fds
)
499 gdb_notifier
.poll_fds
=
500 (struct pollfd
*) xrealloc (gdb_notifier
.poll_fds
,
501 (gdb_notifier
.num_fds
502 * sizeof (struct pollfd
)));
504 gdb_notifier
.poll_fds
=
505 (struct pollfd
*) xmalloc (sizeof (struct pollfd
));
506 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->fd
= fd
;
507 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->events
= mask
;
508 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->revents
= 0;
510 internal_error (__FILE__
, __LINE__
,
511 "use_poll without HAVE_POLL");
512 #endif /* HAVE_POLL */
516 if (mask
& GDB_READABLE
)
517 FD_SET (fd
, &gdb_notifier
.check_masks
[0]);
519 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
521 if (mask
& GDB_WRITABLE
)
522 FD_SET (fd
, &gdb_notifier
.check_masks
[1]);
524 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
526 if (mask
& GDB_EXCEPTION
)
527 FD_SET (fd
, &gdb_notifier
.check_masks
[2]);
529 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
531 if (gdb_notifier
.num_fds
<= fd
)
532 gdb_notifier
.num_fds
= fd
+ 1;
536 /* Remove the file descriptor FD from the list of monitored fd's:
537 i.e. we don't care anymore about events on the FD. */
539 delete_file_handler (int fd
)
541 file_handler
*file_ptr
, *prev_ptr
= NULL
;
545 struct pollfd
*new_poll_fds
;
548 /* Find the entry for the given file. */
550 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
551 file_ptr
= file_ptr
->next_file
)
553 if (file_ptr
->fd
== fd
)
557 if (file_ptr
== NULL
)
563 /* Create a new poll_fds array by copying every fd's information but the
564 one we want to get rid of. */
567 (struct pollfd
*) xmalloc ((gdb_notifier
.num_fds
- 1) * sizeof (struct pollfd
));
569 for (i
= 0, j
= 0; i
< gdb_notifier
.num_fds
; i
++)
571 if ((gdb_notifier
.poll_fds
+ i
)->fd
!= fd
)
573 (new_poll_fds
+ j
)->fd
= (gdb_notifier
.poll_fds
+ i
)->fd
;
574 (new_poll_fds
+ j
)->events
= (gdb_notifier
.poll_fds
+ i
)->events
;
575 (new_poll_fds
+ j
)->revents
= (gdb_notifier
.poll_fds
+ i
)->revents
;
579 xfree (gdb_notifier
.poll_fds
);
580 gdb_notifier
.poll_fds
= new_poll_fds
;
581 gdb_notifier
.num_fds
--;
583 internal_error (__FILE__
, __LINE__
,
584 "use_poll without HAVE_POLL");
585 #endif /* HAVE_POLL */
589 if (file_ptr
->mask
& GDB_READABLE
)
590 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
591 if (file_ptr
->mask
& GDB_WRITABLE
)
592 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
593 if (file_ptr
->mask
& GDB_EXCEPTION
)
594 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
596 /* Find current max fd. */
598 if ((fd
+ 1) == gdb_notifier
.num_fds
)
600 gdb_notifier
.num_fds
--;
601 for (i
= gdb_notifier
.num_fds
; i
; i
--)
603 if (FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[0])
604 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[1])
605 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[2]))
608 gdb_notifier
.num_fds
= i
;
612 /* Deactivate the file descriptor, by clearing its mask,
613 so that it will not fire again. */
617 /* Get rid of the file handler in the file handler list. */
618 if (file_ptr
== gdb_notifier
.first_file_handler
)
619 gdb_notifier
.first_file_handler
= file_ptr
->next_file
;
622 for (prev_ptr
= gdb_notifier
.first_file_handler
;
623 prev_ptr
->next_file
!= file_ptr
;
624 prev_ptr
= prev_ptr
->next_file
)
626 prev_ptr
->next_file
= file_ptr
->next_file
;
631 /* Handle the given event by calling the procedure associated to the
632 corresponding file handler. Called by process_event indirectly,
633 through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the
634 event in the front of the event queue. */
636 handle_file_event (int event_file_desc
)
638 file_handler
*file_ptr
;
642 int error_mask_returned
;
645 /* Search the file handler list to find one that matches the fd in
647 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
648 file_ptr
= file_ptr
->next_file
)
650 if (file_ptr
->fd
== event_file_desc
)
652 /* With poll, the ready_mask could have any of three events
653 set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot
654 be used in the requested event mask (events), but they
655 can be returned in the return mask (revents). We need to
656 check for those event too, and add them to the mask which
657 will be passed to the handler. */
659 /* See if the desired events (mask) match the received
660 events (ready_mask). */
665 error_mask
= POLLHUP
| POLLERR
| POLLNVAL
;
666 mask
= (file_ptr
->ready_mask
& file_ptr
->mask
) |
667 (file_ptr
->ready_mask
& error_mask
);
668 error_mask_returned
= mask
& error_mask
;
670 if (error_mask_returned
!= 0)
672 /* Work in progress. We may need to tell somebody what
673 kind of error we had. */
674 if (error_mask_returned
& POLLHUP
)
675 printf_unfiltered ("Hangup detected on fd %d\n", file_ptr
->fd
);
676 if (error_mask_returned
& POLLERR
)
677 printf_unfiltered ("Error detected on fd %d\n", file_ptr
->fd
);
678 if (error_mask_returned
& POLLNVAL
)
679 printf_unfiltered ("Invalid or non-`poll'able fd %d\n", file_ptr
->fd
);
685 internal_error (__FILE__
, __LINE__
,
686 "use_poll without HAVE_POLL");
687 #endif /* HAVE_POLL */
691 if (file_ptr
->ready_mask
& GDB_EXCEPTION
)
693 printf_unfiltered ("Exception condition detected on fd %d\n", file_ptr
->fd
);
698 mask
= file_ptr
->ready_mask
& file_ptr
->mask
;
701 /* Clear the received events for next time around. */
702 file_ptr
->ready_mask
= 0;
704 /* If there was a match, then call the handler. */
706 (*file_ptr
->proc
) (file_ptr
->error
, file_ptr
->client_data
);
712 /* Called by gdb_do_one_event to wait for new events on the
713 monitored file descriptors. Queue file events as they are
714 detected by the poll.
715 If there are no events, this function will block in the
717 Return -1 if there are no files descriptors to monitor,
718 otherwise return 0. */
720 gdb_wait_for_event (void)
722 file_handler
*file_ptr
;
723 gdb_event
*file_event_ptr
;
727 /* Make sure all output is done before getting another event. */
728 gdb_flush (gdb_stdout
);
729 gdb_flush (gdb_stderr
);
731 if (gdb_notifier
.num_fds
== 0)
738 poll (gdb_notifier
.poll_fds
,
739 (unsigned long) gdb_notifier
.num_fds
,
740 gdb_notifier
.timeout_valid
? gdb_notifier
.poll_timeout
: -1);
742 /* Don't print anything if we get out of poll because of a
744 if (num_found
== -1 && errno
!= EINTR
)
745 perror_with_name ("Poll");
747 internal_error (__FILE__
, __LINE__
,
748 "use_poll without HAVE_POLL");
749 #endif /* HAVE_POLL */
753 gdb_notifier
.ready_masks
[0] = gdb_notifier
.check_masks
[0];
754 gdb_notifier
.ready_masks
[1] = gdb_notifier
.check_masks
[1];
755 gdb_notifier
.ready_masks
[2] = gdb_notifier
.check_masks
[2];
756 num_found
= select (gdb_notifier
.num_fds
,
757 &gdb_notifier
.ready_masks
[0],
758 &gdb_notifier
.ready_masks
[1],
759 &gdb_notifier
.ready_masks
[2],
760 gdb_notifier
.timeout_valid
761 ? &gdb_notifier
.select_timeout
: NULL
);
763 /* Clear the masks after an error from select. */
766 FD_ZERO (&gdb_notifier
.ready_masks
[0]);
767 FD_ZERO (&gdb_notifier
.ready_masks
[1]);
768 FD_ZERO (&gdb_notifier
.ready_masks
[2]);
769 /* Dont print anything is we got a signal, let gdb handle it. */
771 perror_with_name ("Select");
775 /* Enqueue all detected file events. */
780 for (i
= 0; (i
< gdb_notifier
.num_fds
) && (num_found
> 0); i
++)
782 if ((gdb_notifier
.poll_fds
+ i
)->revents
)
787 for (file_ptr
= gdb_notifier
.first_file_handler
;
789 file_ptr
= file_ptr
->next_file
)
791 if (file_ptr
->fd
== (gdb_notifier
.poll_fds
+ i
)->fd
)
797 /* Enqueue an event only if this is still a new event for
799 if (file_ptr
->ready_mask
== 0)
801 file_event_ptr
= create_file_event (file_ptr
->fd
);
802 async_queue_event (file_event_ptr
, TAIL
);
806 file_ptr
->ready_mask
= (gdb_notifier
.poll_fds
+ i
)->revents
;
809 internal_error (__FILE__
, __LINE__
,
810 "use_poll without HAVE_POLL");
811 #endif /* HAVE_POLL */
815 for (file_ptr
= gdb_notifier
.first_file_handler
;
816 (file_ptr
!= NULL
) && (num_found
> 0);
817 file_ptr
= file_ptr
->next_file
)
821 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[0]))
822 mask
|= GDB_READABLE
;
823 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[1]))
824 mask
|= GDB_WRITABLE
;
825 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[2]))
826 mask
|= GDB_EXCEPTION
;
833 /* Enqueue an event only if this is still a new event for
836 if (file_ptr
->ready_mask
== 0)
838 file_event_ptr
= create_file_event (file_ptr
->fd
);
839 async_queue_event (file_event_ptr
, TAIL
);
841 file_ptr
->ready_mask
= mask
;
848 /* Create an asynchronous handler, allocating memory for it.
849 Return a pointer to the newly created handler.
850 This pointer will be used to invoke the handler by
851 invoke_async_signal_handler.
852 PROC is the function to call with CLIENT_DATA argument
853 whenever the handler is invoked. */
854 async_signal_handler
*
855 create_async_signal_handler (sig_handler_func
* proc
, gdb_client_data client_data
)
857 async_signal_handler
*async_handler_ptr
;
860 (async_signal_handler
*) xmalloc (sizeof (async_signal_handler
));
861 async_handler_ptr
->ready
= 0;
862 async_handler_ptr
->next_handler
= NULL
;
863 async_handler_ptr
->proc
= proc
;
864 async_handler_ptr
->client_data
= client_data
;
865 if (sighandler_list
.first_handler
== NULL
)
866 sighandler_list
.first_handler
= async_handler_ptr
;
868 sighandler_list
.last_handler
->next_handler
= async_handler_ptr
;
869 sighandler_list
.last_handler
= async_handler_ptr
;
870 return async_handler_ptr
;
873 /* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will
874 be used when the handlers are invoked, after we have waited for
875 some event. The caller of this function is the interrupt handler
876 associated with a signal. */
878 mark_async_signal_handler (async_signal_handler
* async_handler_ptr
)
880 ((async_signal_handler
*) async_handler_ptr
)->ready
= 1;
881 async_handler_ready
= 1;
884 /* Call all the handlers that are ready. */
886 invoke_async_signal_handler (void)
888 async_signal_handler
*async_handler_ptr
;
890 if (async_handler_ready
== 0)
892 async_handler_ready
= 0;
894 /* Invoke ready handlers. */
898 for (async_handler_ptr
= sighandler_list
.first_handler
;
899 async_handler_ptr
!= NULL
;
900 async_handler_ptr
= async_handler_ptr
->next_handler
)
902 if (async_handler_ptr
->ready
)
905 if (async_handler_ptr
== NULL
)
907 async_handler_ptr
->ready
= 0;
908 (*async_handler_ptr
->proc
) (async_handler_ptr
->client_data
);
914 /* Delete an asynchronous handler (ASYNC_HANDLER_PTR).
915 Free the space allocated for it. */
917 delete_async_signal_handler (async_signal_handler
** async_handler_ptr
)
919 async_signal_handler
*prev_ptr
;
921 if (sighandler_list
.first_handler
== (*async_handler_ptr
))
923 sighandler_list
.first_handler
= (*async_handler_ptr
)->next_handler
;
924 if (sighandler_list
.first_handler
== NULL
)
925 sighandler_list
.last_handler
= NULL
;
929 prev_ptr
= sighandler_list
.first_handler
;
930 while (prev_ptr
->next_handler
!= (*async_handler_ptr
) && prev_ptr
)
931 prev_ptr
= prev_ptr
->next_handler
;
932 prev_ptr
->next_handler
= (*async_handler_ptr
)->next_handler
;
933 if (sighandler_list
.last_handler
== (*async_handler_ptr
))
934 sighandler_list
.last_handler
= prev_ptr
;
936 xfree ((*async_handler_ptr
));
937 (*async_handler_ptr
) = NULL
;
940 /* Is it necessary to call invoke_async_signal_handler? */
942 check_async_ready (void)
944 return async_handler_ready
;
947 /* Create a timer that will expire in MILLISECONDS from now. When the
948 timer is ready, PROC will be executed. At creation, the timer is
949 aded to the timers queue. This queue is kept sorted in order of
950 increasing timers. Return a handle to the timer struct. */
952 create_timer (int milliseconds
, timer_handler_func
* proc
, gdb_client_data client_data
)
954 struct gdb_timer
*timer_ptr
, *timer_index
, *prev_timer
;
955 struct timeval time_now
, delta
;
957 /* compute seconds */
958 delta
.tv_sec
= milliseconds
/ 1000;
959 /* compute microseconds */
960 delta
.tv_usec
= (milliseconds
% 1000) * 1000;
962 gettimeofday (&time_now
, NULL
);
964 timer_ptr
= (struct gdb_timer
*) xmalloc (sizeof (gdb_timer
));
965 timer_ptr
->when
.tv_sec
= time_now
.tv_sec
+ delta
.tv_sec
;
966 timer_ptr
->when
.tv_usec
= time_now
.tv_usec
+ delta
.tv_usec
;
968 if (timer_ptr
->when
.tv_usec
>= 1000000)
970 timer_ptr
->when
.tv_sec
+= 1;
971 timer_ptr
->when
.tv_usec
-= 1000000;
973 timer_ptr
->proc
= proc
;
974 timer_ptr
->client_data
= client_data
;
975 timer_list
.num_timers
++;
976 timer_ptr
->timer_id
= timer_list
.num_timers
;
978 /* Now add the timer to the timer queue, making sure it is sorted in
979 increasing order of expiration. */
981 for (timer_index
= timer_list
.first_timer
;
983 timer_index
= timer_index
->next
)
985 /* If the seconds field is greater or if it is the same, but the
986 microsecond field is greater. */
987 if ((timer_index
->when
.tv_sec
> timer_ptr
->when
.tv_sec
) ||
988 ((timer_index
->when
.tv_sec
== timer_ptr
->when
.tv_sec
)
989 && (timer_index
->when
.tv_usec
> timer_ptr
->when
.tv_usec
)))
993 if (timer_index
== timer_list
.first_timer
)
995 timer_ptr
->next
= timer_list
.first_timer
;
996 timer_list
.first_timer
= timer_ptr
;
1001 for (prev_timer
= timer_list
.first_timer
;
1002 prev_timer
->next
!= timer_index
;
1003 prev_timer
= prev_timer
->next
)
1006 prev_timer
->next
= timer_ptr
;
1007 timer_ptr
->next
= timer_index
;
1010 gdb_notifier
.timeout_valid
= 0;
1011 return timer_ptr
->timer_id
;
1014 /* There is a chance that the creator of the timer wants to get rid of
1015 it before it expires. */
1017 delete_timer (int id
)
1019 struct gdb_timer
*timer_ptr
, *prev_timer
= NULL
;
1021 /* Find the entry for the given timer. */
1023 for (timer_ptr
= timer_list
.first_timer
; timer_ptr
!= NULL
;
1024 timer_ptr
= timer_ptr
->next
)
1026 if (timer_ptr
->timer_id
== id
)
1030 if (timer_ptr
== NULL
)
1032 /* Get rid of the timer in the timer list. */
1033 if (timer_ptr
== timer_list
.first_timer
)
1034 timer_list
.first_timer
= timer_ptr
->next
;
1037 for (prev_timer
= timer_list
.first_timer
;
1038 prev_timer
->next
!= timer_ptr
;
1039 prev_timer
= prev_timer
->next
)
1041 prev_timer
->next
= timer_ptr
->next
;
1045 gdb_notifier
.timeout_valid
= 0;
1048 /* When a timer event is put on the event queue, it will be handled by
1049 this function. Just call the assiciated procedure and delete the
1050 timer event from the event queue. Repeat this for each timer that
1053 handle_timer_event (int dummy
)
1055 struct timeval time_now
;
1056 struct gdb_timer
*timer_ptr
, *saved_timer
;
1058 gettimeofday (&time_now
, NULL
);
1059 timer_ptr
= timer_list
.first_timer
;
1061 while (timer_ptr
!= NULL
)
1063 if ((timer_ptr
->when
.tv_sec
> time_now
.tv_sec
) ||
1064 ((timer_ptr
->when
.tv_sec
== time_now
.tv_sec
) &&
1065 (timer_ptr
->when
.tv_usec
> time_now
.tv_usec
)))
1068 /* Get rid of the timer from the beginning of the list. */
1069 timer_list
.first_timer
= timer_ptr
->next
;
1070 saved_timer
= timer_ptr
;
1071 timer_ptr
= timer_ptr
->next
;
1072 /* Call the procedure associated with that timer. */
1073 (*saved_timer
->proc
) (saved_timer
->client_data
);
1074 xfree (saved_timer
);
1077 gdb_notifier
.timeout_valid
= 0;
1080 /* Check whether any timers in the timers queue are ready. If at least
1081 one timer is ready, stick an event onto the event queue. Even in
1082 case more than one timer is ready, one event is enough, because the
1083 handle_timer_event() will go through the timers list and call the
1084 procedures associated with all that have expired. Update the
1085 timeout for the select() or poll() as well. */
1089 struct timeval time_now
, delta
;
1090 gdb_event
*event_ptr
;
1092 if (timer_list
.first_timer
!= NULL
)
1094 gettimeofday (&time_now
, NULL
);
1095 delta
.tv_sec
= timer_list
.first_timer
->when
.tv_sec
- time_now
.tv_sec
;
1096 delta
.tv_usec
= timer_list
.first_timer
->when
.tv_usec
- time_now
.tv_usec
;
1098 if (delta
.tv_usec
< 0)
1101 delta
.tv_usec
+= 1000000;
1104 /* Oops it expired already. Tell select / poll to return
1105 immediately. (Cannot simply test if delta.tv_sec is negative
1106 because time_t might be unsigned.) */
1107 if (timer_list
.first_timer
->when
.tv_sec
< time_now
.tv_sec
1108 || (timer_list
.first_timer
->when
.tv_sec
== time_now
.tv_sec
1109 && timer_list
.first_timer
->when
.tv_usec
< time_now
.tv_usec
))
1115 if (delta
.tv_sec
== 0 && delta
.tv_usec
== 0)
1117 event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
1118 event_ptr
->proc
= handle_timer_event
;
1119 event_ptr
->fd
= timer_list
.first_timer
->timer_id
;
1120 async_queue_event (event_ptr
, TAIL
);
1123 /* Now we need to update the timeout for select/ poll, because we
1124 don't want to sit there while this timer is expiring. */
1128 gdb_notifier
.poll_timeout
= delta
.tv_sec
* 1000;
1130 internal_error (__FILE__
, __LINE__
,
1131 "use_poll without HAVE_POLL");
1132 #endif /* HAVE_POLL */
1136 gdb_notifier
.select_timeout
.tv_sec
= delta
.tv_sec
;
1137 gdb_notifier
.select_timeout
.tv_usec
= delta
.tv_usec
;
1139 gdb_notifier
.timeout_valid
= 1;
1142 gdb_notifier
.timeout_valid
= 0;