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.
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"
38 #include "exceptions.h"
40 typedef struct gdb_event gdb_event
;
41 typedef void (event_handler_func
) (int);
43 /* Event for the GDB event system. Events are queued by calling
44 async_queue_event and serviced later on by gdb_do_one_event. An
45 event can be, for instance, a file descriptor becoming ready to be
46 read. Servicing an event simply means that the procedure PROC will
47 be called. We have 2 queues, one for file handlers that we listen
48 to in the event loop, and one for the file handlers+events that are
49 ready. The procedure PROC associated with each event is always the
50 same (handle_file_event). Its duty is to invoke the handler
51 associated with the file descriptor whose state change generated
52 the event, plus doing other cleanups and such. */
56 event_handler_func
*proc
; /* Procedure to call to service this event. */
57 int fd
; /* File descriptor that is ready. */
58 struct gdb_event
*next_event
; /* Next in list of events or NULL. */
61 /* Information about each file descriptor we register with the event
64 typedef struct file_handler
66 int fd
; /* File descriptor. */
67 int mask
; /* Events we want to monitor: POLLIN, etc. */
68 int ready_mask
; /* Events that have been seen since
70 handler_func
*proc
; /* Procedure to call when fd is ready. */
71 gdb_client_data client_data
; /* Argument to pass to proc. */
72 int error
; /* Was an error detected on this fd? */
73 struct file_handler
*next_file
; /* Next registered file descriptor. */
77 /* PROC is a function to be invoked when the READY flag is set. This
78 happens when there has been a signal and the corresponding signal
79 handler has 'triggered' this async_signal_handler for
80 execution. The actual work to be done in response to a signal will
81 be carried out by PROC at a later time, within process_event. This
82 provides a deferred execution of signal handlers.
83 Async_init_signals takes care of setting up such an
84 asyn_signal_handler for each interesting signal. */
85 typedef struct async_signal_handler
87 int ready
; /* If ready, call this handler from the main event loop,
88 using invoke_async_handler. */
89 struct async_signal_handler
*next_handler
; /* Ptr to next handler */
90 sig_handler_func
*proc
; /* Function to call to do the work */
91 gdb_client_data client_data
; /* Argument to async_handler_func */
97 - the first event in the queue is the head of the queue.
98 It will be the next to be serviced.
99 - the last event in the queue
101 Events can be inserted at the front of the queue or at the end of
102 the queue. Events will be extracted from the queue for processing
103 starting from the head. Therefore, events inserted at the head of
104 the queue will be processed in a last in first out fashion, while
105 those inserted at the tail of the queue will be processed in a first
106 in first out manner. All the fields are NULL if the queue is
111 gdb_event
*first_event
; /* First pending event */
112 gdb_event
*last_event
; /* Last pending event */
116 /* Gdb_notifier is just a list of file descriptors gdb is interested in.
117 These are the input file descriptor, and the target file
118 descriptor. We have two flavors of the notifier, one for platforms
119 that have the POLL function, the other for those that don't, and
120 only support SELECT. Each of the elements in the gdb_notifier list is
121 basically a description of what kind of events gdb is interested
124 /* As of 1999-04-30 only the input file descriptor is registered with the
127 /* Do we use poll or select ? */
132 #endif /* HAVE_POLL */
134 static unsigned char use_poll
= USE_POLL
;
138 /* Ptr to head of file handler list. */
139 file_handler
*first_file_handler
;
142 /* Ptr to array of pollfd structures. */
143 struct pollfd
*poll_fds
;
145 /* Timeout in milliseconds for calls to poll(). */
149 /* Masks to be used in the next call to select.
150 Bits are set in response to calls to create_file_handler. */
151 fd_set check_masks
[3];
153 /* What file descriptors were found ready by select. */
154 fd_set ready_masks
[3];
156 /* Number of file descriptors to monitor. (for poll) */
157 /* Number of valid bits (highest fd value + 1). (for select) */
160 /* Time structure for calls to select(). */
161 struct timeval select_timeout
;
163 /* Flag to tell whether the timeout should be used. */
168 /* Structure associated with a timer. PROC will be executed at the
169 first occasion after WHEN. */
174 struct gdb_timer
*next
;
175 timer_handler_func
*proc
; /* Function to call to do the work */
176 gdb_client_data client_data
; /* Argument to async_handler_func */
180 /* List of currently active timers. It is sorted in order of
181 increasing timers. */
184 /* Pointer to first in timer list. */
185 struct gdb_timer
*first_timer
;
187 /* Id of the last timer created. */
192 /* All the async_signal_handlers gdb is interested in are kept onto
196 /* Pointer to first in handler list. */
197 async_signal_handler
*first_handler
;
199 /* Pointer to last in handler list. */
200 async_signal_handler
*last_handler
;
204 /* Are any of the handlers ready? Check this variable using
205 check_async_ready. This is used by process_event, to determine
206 whether or not to invoke the invoke_async_signal_handler
208 static int async_handler_ready
= 0;
210 static void create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
);
211 static void invoke_async_signal_handler (void);
212 static void handle_file_event (int event_file_desc
);
213 static int gdb_wait_for_event (void);
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. */
398 gdb_result
= catch_errors (gdb_do_one_event
, 0, "", RETURN_MASK_ALL
);
402 /* If we long-jumped out of do_one_event, we probably
403 didn't get around to resetting the prompt, which leaves
404 readline in a messed-up state. Reset it here. */
408 /* FIXME: this should really be a call to a hook that is
409 interface specific, because interfaces can display the
410 prompt in their own way. */
411 display_gdb_prompt (0);
412 /* This call looks bizarre, but it is required. If the user
413 entered a command that caused an error,
414 after_char_processing_hook won't be called from
415 rl_callback_read_char_wrapper. Using a cleanup there
416 won't work, since we want this function to be called
417 after a new prompt is printed. */
418 if (after_char_processing_hook
)
419 (*after_char_processing_hook
) ();
420 /* Maybe better to set a flag to be checked somewhere as to
421 whether display the prompt or not. */
425 /* We are done with the event loop. There are no more event sources
426 to listen to. So we exit GDB. */
431 /* Wrapper function for create_file_handler, so that the caller
432 doesn't have to know implementation details about the use of poll
435 add_file_handler (int fd
, handler_func
* proc
, gdb_client_data client_data
)
444 /* Check to see if poll () is usable. If not, we'll switch to
445 use select. This can happen on systems like
446 m68k-motorola-sys, `poll' cannot be used to wait for `stdin'.
447 On m68k-motorola-sysv, tty's are not stream-based and not
451 if (poll (&fds
, 1, 0) == 1 && (fds
.revents
& POLLNVAL
))
454 internal_error (__FILE__
, __LINE__
,
455 _("use_poll without HAVE_POLL"));
456 #endif /* HAVE_POLL */
461 create_file_handler (fd
, POLLIN
, proc
, client_data
);
463 internal_error (__FILE__
, __LINE__
,
464 _("use_poll without HAVE_POLL"));
468 create_file_handler (fd
, GDB_READABLE
| GDB_EXCEPTION
, proc
, client_data
);
471 /* Add a file handler/descriptor to the list of descriptors we are
473 FD is the file descriptor for the file/stream to be listened to.
474 For the poll case, MASK is a combination (OR) of
475 POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM,
476 POLLWRBAND: these are the events we are interested in. If any of them
477 occurs, proc should be called.
478 For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION.
479 PROC is the procedure that will be called when an event occurs for
480 FD. CLIENT_DATA is the argument to pass to PROC. */
482 create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
)
484 file_handler
*file_ptr
;
486 /* Do we already have a file handler for this file? (We may be
487 changing its associated procedure). */
488 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
489 file_ptr
= file_ptr
->next_file
)
491 if (file_ptr
->fd
== fd
)
495 /* It is a new file descriptor. Add it to the list. Otherwise, just
496 change the data associated with it. */
497 if (file_ptr
== NULL
)
499 file_ptr
= (file_handler
*) xmalloc (sizeof (file_handler
));
501 file_ptr
->ready_mask
= 0;
502 file_ptr
->next_file
= gdb_notifier
.first_file_handler
;
503 gdb_notifier
.first_file_handler
= file_ptr
;
508 gdb_notifier
.num_fds
++;
509 if (gdb_notifier
.poll_fds
)
510 gdb_notifier
.poll_fds
=
511 (struct pollfd
*) xrealloc (gdb_notifier
.poll_fds
,
512 (gdb_notifier
.num_fds
513 * sizeof (struct pollfd
)));
515 gdb_notifier
.poll_fds
=
516 (struct pollfd
*) xmalloc (sizeof (struct pollfd
));
517 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->fd
= fd
;
518 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->events
= mask
;
519 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->revents
= 0;
521 internal_error (__FILE__
, __LINE__
,
522 _("use_poll without HAVE_POLL"));
523 #endif /* HAVE_POLL */
527 if (mask
& GDB_READABLE
)
528 FD_SET (fd
, &gdb_notifier
.check_masks
[0]);
530 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
532 if (mask
& GDB_WRITABLE
)
533 FD_SET (fd
, &gdb_notifier
.check_masks
[1]);
535 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
537 if (mask
& GDB_EXCEPTION
)
538 FD_SET (fd
, &gdb_notifier
.check_masks
[2]);
540 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
542 if (gdb_notifier
.num_fds
<= fd
)
543 gdb_notifier
.num_fds
= fd
+ 1;
547 file_ptr
->proc
= proc
;
548 file_ptr
->client_data
= client_data
;
549 file_ptr
->mask
= mask
;
552 /* Remove the file descriptor FD from the list of monitored fd's:
553 i.e. we don't care anymore about events on the FD. */
555 delete_file_handler (int fd
)
557 file_handler
*file_ptr
, *prev_ptr
= NULL
;
561 struct pollfd
*new_poll_fds
;
564 /* Find the entry for the given file. */
566 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
567 file_ptr
= file_ptr
->next_file
)
569 if (file_ptr
->fd
== fd
)
573 if (file_ptr
== NULL
)
579 /* Create a new poll_fds array by copying every fd's information but the
580 one we want to get rid of. */
583 (struct pollfd
*) xmalloc ((gdb_notifier
.num_fds
- 1) * sizeof (struct pollfd
));
585 for (i
= 0, j
= 0; i
< gdb_notifier
.num_fds
; i
++)
587 if ((gdb_notifier
.poll_fds
+ i
)->fd
!= fd
)
589 (new_poll_fds
+ j
)->fd
= (gdb_notifier
.poll_fds
+ i
)->fd
;
590 (new_poll_fds
+ j
)->events
= (gdb_notifier
.poll_fds
+ i
)->events
;
591 (new_poll_fds
+ j
)->revents
= (gdb_notifier
.poll_fds
+ i
)->revents
;
595 xfree (gdb_notifier
.poll_fds
);
596 gdb_notifier
.poll_fds
= new_poll_fds
;
597 gdb_notifier
.num_fds
--;
599 internal_error (__FILE__
, __LINE__
,
600 _("use_poll without HAVE_POLL"));
601 #endif /* HAVE_POLL */
605 if (file_ptr
->mask
& GDB_READABLE
)
606 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
607 if (file_ptr
->mask
& GDB_WRITABLE
)
608 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
609 if (file_ptr
->mask
& GDB_EXCEPTION
)
610 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
612 /* Find current max fd. */
614 if ((fd
+ 1) == gdb_notifier
.num_fds
)
616 gdb_notifier
.num_fds
--;
617 for (i
= gdb_notifier
.num_fds
; i
; i
--)
619 if (FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[0])
620 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[1])
621 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[2]))
624 gdb_notifier
.num_fds
= i
;
628 /* Deactivate the file descriptor, by clearing its mask,
629 so that it will not fire again. */
633 /* Get rid of the file handler in the file handler list. */
634 if (file_ptr
== gdb_notifier
.first_file_handler
)
635 gdb_notifier
.first_file_handler
= file_ptr
->next_file
;
638 for (prev_ptr
= gdb_notifier
.first_file_handler
;
639 prev_ptr
->next_file
!= file_ptr
;
640 prev_ptr
= prev_ptr
->next_file
)
642 prev_ptr
->next_file
= file_ptr
->next_file
;
647 /* Handle the given event by calling the procedure associated to the
648 corresponding file handler. Called by process_event indirectly,
649 through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the
650 event in the front of the event queue. */
652 handle_file_event (int event_file_desc
)
654 file_handler
*file_ptr
;
658 int error_mask_returned
;
661 /* Search the file handler list to find one that matches the fd in
663 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
664 file_ptr
= file_ptr
->next_file
)
666 if (file_ptr
->fd
== event_file_desc
)
668 /* With poll, the ready_mask could have any of three events
669 set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot
670 be used in the requested event mask (events), but they
671 can be returned in the return mask (revents). We need to
672 check for those event too, and add them to the mask which
673 will be passed to the handler. */
675 /* See if the desired events (mask) match the received
676 events (ready_mask). */
681 error_mask
= POLLHUP
| POLLERR
| POLLNVAL
;
682 mask
= (file_ptr
->ready_mask
& file_ptr
->mask
) |
683 (file_ptr
->ready_mask
& error_mask
);
684 error_mask_returned
= mask
& error_mask
;
686 if (error_mask_returned
!= 0)
688 /* Work in progress. We may need to tell somebody what
689 kind of error we had. */
690 if (error_mask_returned
& POLLHUP
)
691 printf_unfiltered (_("Hangup detected on fd %d\n"), file_ptr
->fd
);
692 if (error_mask_returned
& POLLERR
)
693 printf_unfiltered (_("Error detected on fd %d\n"), file_ptr
->fd
);
694 if (error_mask_returned
& POLLNVAL
)
695 printf_unfiltered (_("Invalid or non-`poll'able fd %d\n"), file_ptr
->fd
);
701 internal_error (__FILE__
, __LINE__
,
702 _("use_poll without HAVE_POLL"));
703 #endif /* HAVE_POLL */
707 if (file_ptr
->ready_mask
& GDB_EXCEPTION
)
709 printf_unfiltered (_("Exception condition detected on fd %d\n"), file_ptr
->fd
);
714 mask
= file_ptr
->ready_mask
& file_ptr
->mask
;
717 /* Clear the received events for next time around. */
718 file_ptr
->ready_mask
= 0;
720 /* If there was a match, then call the handler. */
722 (*file_ptr
->proc
) (file_ptr
->error
, file_ptr
->client_data
);
728 /* Called by gdb_do_one_event to wait for new events on the
729 monitored file descriptors. Queue file events as they are
730 detected by the poll.
731 If there are no events, this function will block in the
733 Return -1 if there are no files descriptors to monitor,
734 otherwise return 0. */
736 gdb_wait_for_event (void)
738 file_handler
*file_ptr
;
739 gdb_event
*file_event_ptr
;
743 /* Make sure all output is done before getting another event. */
744 gdb_flush (gdb_stdout
);
745 gdb_flush (gdb_stderr
);
747 if (gdb_notifier
.num_fds
== 0)
754 poll (gdb_notifier
.poll_fds
,
755 (unsigned long) gdb_notifier
.num_fds
,
756 gdb_notifier
.timeout_valid
? gdb_notifier
.poll_timeout
: -1);
758 /* Don't print anything if we get out of poll because of a
760 if (num_found
== -1 && errno
!= EINTR
)
761 perror_with_name (("poll"));
763 internal_error (__FILE__
, __LINE__
,
764 _("use_poll without HAVE_POLL"));
765 #endif /* HAVE_POLL */
769 gdb_notifier
.ready_masks
[0] = gdb_notifier
.check_masks
[0];
770 gdb_notifier
.ready_masks
[1] = gdb_notifier
.check_masks
[1];
771 gdb_notifier
.ready_masks
[2] = gdb_notifier
.check_masks
[2];
772 num_found
= select (gdb_notifier
.num_fds
,
773 &gdb_notifier
.ready_masks
[0],
774 &gdb_notifier
.ready_masks
[1],
775 &gdb_notifier
.ready_masks
[2],
776 gdb_notifier
.timeout_valid
777 ? &gdb_notifier
.select_timeout
: NULL
);
779 /* Clear the masks after an error from select. */
782 FD_ZERO (&gdb_notifier
.ready_masks
[0]);
783 FD_ZERO (&gdb_notifier
.ready_masks
[1]);
784 FD_ZERO (&gdb_notifier
.ready_masks
[2]);
785 /* Dont print anything is we got a signal, let gdb handle it. */
787 perror_with_name (("select"));
791 /* Enqueue all detected file events. */
796 for (i
= 0; (i
< gdb_notifier
.num_fds
) && (num_found
> 0); i
++)
798 if ((gdb_notifier
.poll_fds
+ i
)->revents
)
803 for (file_ptr
= gdb_notifier
.first_file_handler
;
805 file_ptr
= file_ptr
->next_file
)
807 if (file_ptr
->fd
== (gdb_notifier
.poll_fds
+ i
)->fd
)
813 /* Enqueue an event only if this is still a new event for
815 if (file_ptr
->ready_mask
== 0)
817 file_event_ptr
= create_file_event (file_ptr
->fd
);
818 async_queue_event (file_event_ptr
, TAIL
);
822 file_ptr
->ready_mask
= (gdb_notifier
.poll_fds
+ i
)->revents
;
825 internal_error (__FILE__
, __LINE__
,
826 _("use_poll without HAVE_POLL"));
827 #endif /* HAVE_POLL */
831 for (file_ptr
= gdb_notifier
.first_file_handler
;
832 (file_ptr
!= NULL
) && (num_found
> 0);
833 file_ptr
= file_ptr
->next_file
)
837 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[0]))
838 mask
|= GDB_READABLE
;
839 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[1]))
840 mask
|= GDB_WRITABLE
;
841 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[2]))
842 mask
|= GDB_EXCEPTION
;
849 /* Enqueue an event only if this is still a new event for
852 if (file_ptr
->ready_mask
== 0)
854 file_event_ptr
= create_file_event (file_ptr
->fd
);
855 async_queue_event (file_event_ptr
, TAIL
);
857 file_ptr
->ready_mask
= mask
;
864 /* Create an asynchronous handler, allocating memory for it.
865 Return a pointer to the newly created handler.
866 This pointer will be used to invoke the handler by
867 invoke_async_signal_handler.
868 PROC is the function to call with CLIENT_DATA argument
869 whenever the handler is invoked. */
870 async_signal_handler
*
871 create_async_signal_handler (sig_handler_func
* proc
, gdb_client_data client_data
)
873 async_signal_handler
*async_handler_ptr
;
876 (async_signal_handler
*) xmalloc (sizeof (async_signal_handler
));
877 async_handler_ptr
->ready
= 0;
878 async_handler_ptr
->next_handler
= NULL
;
879 async_handler_ptr
->proc
= proc
;
880 async_handler_ptr
->client_data
= client_data
;
881 if (sighandler_list
.first_handler
== NULL
)
882 sighandler_list
.first_handler
= async_handler_ptr
;
884 sighandler_list
.last_handler
->next_handler
= async_handler_ptr
;
885 sighandler_list
.last_handler
= async_handler_ptr
;
886 return async_handler_ptr
;
889 /* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will
890 be used when the handlers are invoked, after we have waited for
891 some event. The caller of this function is the interrupt handler
892 associated with a signal. */
894 mark_async_signal_handler (async_signal_handler
* async_handler_ptr
)
896 ((async_signal_handler
*) async_handler_ptr
)->ready
= 1;
897 async_handler_ready
= 1;
900 /* Call all the handlers that are ready. */
902 invoke_async_signal_handler (void)
904 async_signal_handler
*async_handler_ptr
;
906 if (async_handler_ready
== 0)
908 async_handler_ready
= 0;
910 /* Invoke ready handlers. */
914 for (async_handler_ptr
= sighandler_list
.first_handler
;
915 async_handler_ptr
!= NULL
;
916 async_handler_ptr
= async_handler_ptr
->next_handler
)
918 if (async_handler_ptr
->ready
)
921 if (async_handler_ptr
== NULL
)
923 async_handler_ptr
->ready
= 0;
924 (*async_handler_ptr
->proc
) (async_handler_ptr
->client_data
);
930 /* Delete an asynchronous handler (ASYNC_HANDLER_PTR).
931 Free the space allocated for it. */
933 delete_async_signal_handler (async_signal_handler
** async_handler_ptr
)
935 async_signal_handler
*prev_ptr
;
937 if (sighandler_list
.first_handler
== (*async_handler_ptr
))
939 sighandler_list
.first_handler
= (*async_handler_ptr
)->next_handler
;
940 if (sighandler_list
.first_handler
== NULL
)
941 sighandler_list
.last_handler
= NULL
;
945 prev_ptr
= sighandler_list
.first_handler
;
946 while (prev_ptr
->next_handler
!= (*async_handler_ptr
) && prev_ptr
)
947 prev_ptr
= prev_ptr
->next_handler
;
948 prev_ptr
->next_handler
= (*async_handler_ptr
)->next_handler
;
949 if (sighandler_list
.last_handler
== (*async_handler_ptr
))
950 sighandler_list
.last_handler
= prev_ptr
;
952 xfree ((*async_handler_ptr
));
953 (*async_handler_ptr
) = NULL
;
956 /* Is it necessary to call invoke_async_signal_handler? */
958 check_async_ready (void)
960 return async_handler_ready
;
963 /* Create a timer that will expire in MILLISECONDS from now. When the
964 timer is ready, PROC will be executed. At creation, the timer is
965 aded to the timers queue. This queue is kept sorted in order of
966 increasing timers. Return a handle to the timer struct. */
968 create_timer (int milliseconds
, timer_handler_func
* proc
, gdb_client_data client_data
)
970 struct gdb_timer
*timer_ptr
, *timer_index
, *prev_timer
;
971 struct timeval time_now
, delta
;
973 /* compute seconds */
974 delta
.tv_sec
= milliseconds
/ 1000;
975 /* compute microseconds */
976 delta
.tv_usec
= (milliseconds
% 1000) * 1000;
978 gettimeofday (&time_now
, NULL
);
980 timer_ptr
= (struct gdb_timer
*) xmalloc (sizeof (gdb_timer
));
981 timer_ptr
->when
.tv_sec
= time_now
.tv_sec
+ delta
.tv_sec
;
982 timer_ptr
->when
.tv_usec
= time_now
.tv_usec
+ delta
.tv_usec
;
984 if (timer_ptr
->when
.tv_usec
>= 1000000)
986 timer_ptr
->when
.tv_sec
+= 1;
987 timer_ptr
->when
.tv_usec
-= 1000000;
989 timer_ptr
->proc
= proc
;
990 timer_ptr
->client_data
= client_data
;
991 timer_list
.num_timers
++;
992 timer_ptr
->timer_id
= timer_list
.num_timers
;
994 /* Now add the timer to the timer queue, making sure it is sorted in
995 increasing order of expiration. */
997 for (timer_index
= timer_list
.first_timer
;
999 timer_index
= timer_index
->next
)
1001 /* If the seconds field is greater or if it is the same, but the
1002 microsecond field is greater. */
1003 if ((timer_index
->when
.tv_sec
> timer_ptr
->when
.tv_sec
) ||
1004 ((timer_index
->when
.tv_sec
== timer_ptr
->when
.tv_sec
)
1005 && (timer_index
->when
.tv_usec
> timer_ptr
->when
.tv_usec
)))
1009 if (timer_index
== timer_list
.first_timer
)
1011 timer_ptr
->next
= timer_list
.first_timer
;
1012 timer_list
.first_timer
= timer_ptr
;
1017 for (prev_timer
= timer_list
.first_timer
;
1018 prev_timer
->next
!= timer_index
;
1019 prev_timer
= prev_timer
->next
)
1022 prev_timer
->next
= timer_ptr
;
1023 timer_ptr
->next
= timer_index
;
1026 gdb_notifier
.timeout_valid
= 0;
1027 return timer_ptr
->timer_id
;
1030 /* There is a chance that the creator of the timer wants to get rid of
1031 it before it expires. */
1033 delete_timer (int id
)
1035 struct gdb_timer
*timer_ptr
, *prev_timer
= NULL
;
1037 /* Find the entry for the given timer. */
1039 for (timer_ptr
= timer_list
.first_timer
; timer_ptr
!= NULL
;
1040 timer_ptr
= timer_ptr
->next
)
1042 if (timer_ptr
->timer_id
== id
)
1046 if (timer_ptr
== NULL
)
1048 /* Get rid of the timer in the timer list. */
1049 if (timer_ptr
== timer_list
.first_timer
)
1050 timer_list
.first_timer
= timer_ptr
->next
;
1053 for (prev_timer
= timer_list
.first_timer
;
1054 prev_timer
->next
!= timer_ptr
;
1055 prev_timer
= prev_timer
->next
)
1057 prev_timer
->next
= timer_ptr
->next
;
1061 gdb_notifier
.timeout_valid
= 0;
1064 /* When a timer event is put on the event queue, it will be handled by
1065 this function. Just call the assiciated procedure and delete the
1066 timer event from the event queue. Repeat this for each timer that
1069 handle_timer_event (int dummy
)
1071 struct timeval time_now
;
1072 struct gdb_timer
*timer_ptr
, *saved_timer
;
1074 gettimeofday (&time_now
, NULL
);
1075 timer_ptr
= timer_list
.first_timer
;
1077 while (timer_ptr
!= NULL
)
1079 if ((timer_ptr
->when
.tv_sec
> time_now
.tv_sec
) ||
1080 ((timer_ptr
->when
.tv_sec
== time_now
.tv_sec
) &&
1081 (timer_ptr
->when
.tv_usec
> time_now
.tv_usec
)))
1084 /* Get rid of the timer from the beginning of the list. */
1085 timer_list
.first_timer
= timer_ptr
->next
;
1086 saved_timer
= timer_ptr
;
1087 timer_ptr
= timer_ptr
->next
;
1088 /* Call the procedure associated with that timer. */
1089 (*saved_timer
->proc
) (saved_timer
->client_data
);
1090 xfree (saved_timer
);
1093 gdb_notifier
.timeout_valid
= 0;
1096 /* Check whether any timers in the timers queue are ready. If at least
1097 one timer is ready, stick an event onto the event queue. Even in
1098 case more than one timer is ready, one event is enough, because the
1099 handle_timer_event() will go through the timers list and call the
1100 procedures associated with all that have expired. Update the
1101 timeout for the select() or poll() as well. */
1105 struct timeval time_now
, delta
;
1106 gdb_event
*event_ptr
;
1108 if (timer_list
.first_timer
!= NULL
)
1110 gettimeofday (&time_now
, NULL
);
1111 delta
.tv_sec
= timer_list
.first_timer
->when
.tv_sec
- time_now
.tv_sec
;
1112 delta
.tv_usec
= timer_list
.first_timer
->when
.tv_usec
- time_now
.tv_usec
;
1114 if (delta
.tv_usec
< 0)
1117 delta
.tv_usec
+= 1000000;
1120 /* Oops it expired already. Tell select / poll to return
1121 immediately. (Cannot simply test if delta.tv_sec is negative
1122 because time_t might be unsigned.) */
1123 if (timer_list
.first_timer
->when
.tv_sec
< time_now
.tv_sec
1124 || (timer_list
.first_timer
->when
.tv_sec
== time_now
.tv_sec
1125 && timer_list
.first_timer
->when
.tv_usec
< time_now
.tv_usec
))
1131 if (delta
.tv_sec
== 0 && delta
.tv_usec
== 0)
1133 event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
1134 event_ptr
->proc
= handle_timer_event
;
1135 event_ptr
->fd
= timer_list
.first_timer
->timer_id
;
1136 async_queue_event (event_ptr
, TAIL
);
1139 /* Now we need to update the timeout for select/ poll, because we
1140 don't want to sit there while this timer is expiring. */
1144 gdb_notifier
.poll_timeout
= delta
.tv_sec
* 1000;
1146 internal_error (__FILE__
, __LINE__
,
1147 _("use_poll without HAVE_POLL"));
1148 #endif /* HAVE_POLL */
1152 gdb_notifier
.select_timeout
.tv_sec
= delta
.tv_sec
;
1153 gdb_notifier
.select_timeout
.tv_usec
= delta
.tv_usec
;
1155 gdb_notifier
.timeout_valid
= 1;
1158 gdb_notifier
.timeout_valid
= 0;