1 /* Event loop machinery for GDB, the GNU debugger.
2 Copyright 1999, 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. */
24 #include "event-loop.h"
25 #include "event-top.h"
28 #if defined (HAVE_POLL_H)
30 #elif defined (HAVE_SYS_POLL_H)
35 #include <sys/types.h>
36 #include "gdb_string.h"
41 /* Type of the mask arguments to select. */
45 /* All this stuff below is not required if select is used as God(tm)
46 intended, with the FD_* macros. Are there any implementations of
47 select which don't have FD_SET and other standard FD_* macros? I
48 don't think there are, but if I'm wrong, we need to catch them. */
49 #error FD_SET must be defined if select function is to be used!
55 #define SELECT_MASK void
57 #define SELECT_MASK int
60 /* Define "NBBY" (number of bits per byte) if it's not already defined. */
66 /* Define the number of fd_masks in an fd_set */
70 #define FD_SETSIZE OPEN_MAX
72 #define FD_SETSIZE 256
76 #define howmany(x, y) (((x)+((y)-1))/(y))
79 #define NFDBITS NBBY*sizeof(fd_mask)
81 #define MASK_SIZE howmany(FD_SETSIZE, NFDBITS)
83 #endif /* NO_FD_SET */
84 #endif /* !HAVE_POLL */
87 typedef struct gdb_event gdb_event
;
88 typedef void (event_handler_func
) (int);
90 /* Event for the GDB event system. Events are queued by calling
91 async_queue_event and serviced later on by gdb_do_one_event. An
92 event can be, for instance, a file descriptor becoming ready to be
93 read. Servicing an event simply means that the procedure PROC will
94 be called. We have 2 queues, one for file handlers that we listen
95 to in the event loop, and one for the file handlers+events that are
96 ready. The procedure PROC associated with each event is always the
97 same (handle_file_event). Its duty is to invoke the handler
98 associated with the file descriptor whose state change generated
99 the event, plus doing other cleanups and such. */
103 event_handler_func
*proc
; /* Procedure to call to service this event. */
104 int fd
; /* File descriptor that is ready. */
105 struct gdb_event
*next_event
; /* Next in list of events or NULL. */
108 /* Information about each file descriptor we register with the event
111 typedef struct file_handler
113 int fd
; /* File descriptor. */
114 int mask
; /* Events we want to monitor: POLLIN, etc. */
115 int ready_mask
; /* Events that have been seen since
117 handler_func
*proc
; /* Procedure to call when fd is ready. */
118 gdb_client_data client_data
; /* Argument to pass to proc. */
119 int error
; /* Was an error detected on this fd? */
120 struct file_handler
*next_file
; /* Next registered file descriptor. */
124 /* PROC is a function to be invoked when the READY flag is set. This
125 happens when there has been a signal and the corresponding signal
126 handler has 'triggered' this async_signal_handler for
127 execution. The actual work to be done in response to a signal will
128 be carried out by PROC at a later time, within process_event. This
129 provides a deferred execution of signal handlers.
130 Async_init_signals takes care of setting up such an
131 asyn_signal_handler for each interesting signal. */
132 typedef struct async_signal_handler
134 int ready
; /* If ready, call this handler from the main event loop,
135 using invoke_async_handler. */
136 struct async_signal_handler
*next_handler
; /* Ptr to next handler */
137 sig_handler_func
*proc
; /* Function to call to do the work */
138 gdb_client_data client_data
; /* Argument to async_handler_func */
140 async_signal_handler
;
144 - the first event in the queue is the head of the queue.
145 It will be the next to be serviced.
146 - the last event in the queue
148 Events can be inserted at the front of the queue or at the end of
149 the queue. Events will be extracted from the queue for processing
150 starting from the head. Therefore, events inserted at the head of
151 the queue will be processed in a last in first out fashion, while
152 those inserted at the tail of the queue will be processed in a first
153 in first out manner. All the fields are NULL if the queue is
158 gdb_event
*first_event
; /* First pending event */
159 gdb_event
*last_event
; /* Last pending event */
163 /* Gdb_notifier is just a list of file descriptors gdb is interested in.
164 These are the input file descriptor, and the target file
165 descriptor. We have two flavors of the notifier, one for platforms
166 that have the POLL function, the other for those that don't, and
167 only support SELECT. Each of the elements in the gdb_notifier list is
168 basically a description of what kind of events gdb is interested
171 /* As of 1999-04-30 only the input file descriptor is registered with the
174 /* Do we use poll or select ? */
179 #endif /* HAVE_POLL */
181 static unsigned char use_poll
= USE_POLL
;
185 /* Ptr to head of file handler list. */
186 file_handler
*first_file_handler
;
189 /* Ptr to array of pollfd structures. */
190 struct pollfd
*poll_fds
;
192 /* Timeout in milliseconds for calls to poll(). */
196 /* Masks to be used in the next call to select.
197 Bits are set in response to calls to create_file_handler. */
198 fd_set check_masks
[3];
200 /* What file descriptors were found ready by select. */
201 fd_set ready_masks
[3];
203 /* Number of file descriptors to monitor. (for poll) */
204 /* Number of valid bits (highest fd value + 1). (for select) */
207 /* Time structure for calls to select(). */
208 struct timeval select_timeout
;
210 /* Flag to tell whether the timeout should be used. */
215 /* Structure associated with a timer. PROC will be executed at the
216 first occasion after WHEN. */
221 struct gdb_timer
*next
;
222 timer_handler_func
*proc
; /* Function to call to do the work */
223 gdb_client_data client_data
; /* Argument to async_handler_func */
227 /* List of currently active timers. It is sorted in order of
228 increasing timers. */
231 /* Pointer to first in timer list. */
232 struct gdb_timer
*first_timer
;
234 /* Id of the last timer created. */
239 /* All the async_signal_handlers gdb is interested in are kept onto
243 /* Pointer to first in handler list. */
244 async_signal_handler
*first_handler
;
246 /* Pointer to last in handler list. */
247 async_signal_handler
*last_handler
;
251 /* Are any of the handlers ready? Check this variable using
252 check_async_ready. This is used by process_event, to determine
253 whether or not to invoke the invoke_async_signal_handler
255 static int async_handler_ready
= 0;
257 static void create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
);
258 static void invoke_async_signal_handler (void);
259 static void handle_file_event (int event_file_desc
);
260 static int gdb_wait_for_event (void);
261 static int gdb_do_one_event (void *data
);
262 static int check_async_ready (void);
263 static void async_queue_event (gdb_event
* event_ptr
, queue_position position
);
264 static gdb_event
*create_file_event (int fd
);
265 static int process_event (void);
266 static void handle_timer_event (int dummy
);
267 static void poll_timers (void);
270 /* Insert an event object into the gdb event queue at
271 the specified position.
272 POSITION can be head or tail, with values TAIL, HEAD.
273 EVENT_PTR points to the event to be inserted into the queue.
274 The caller must allocate memory for the event. It is freed
275 after the event has ben handled.
276 Events in the queue will be processed head to tail, therefore,
277 events inserted at the head of the queue will be processed
278 as last in first out. Event appended at the tail of the queue
279 will be processed first in first out. */
281 async_queue_event (gdb_event
* event_ptr
, queue_position position
)
283 if (position
== TAIL
)
285 /* The event will become the new last_event. */
287 event_ptr
->next_event
= NULL
;
288 if (event_queue
.first_event
== NULL
)
289 event_queue
.first_event
= event_ptr
;
291 event_queue
.last_event
->next_event
= event_ptr
;
292 event_queue
.last_event
= event_ptr
;
294 else if (position
== HEAD
)
296 /* The event becomes the new first_event. */
298 event_ptr
->next_event
= event_queue
.first_event
;
299 if (event_queue
.first_event
== NULL
)
300 event_queue
.last_event
= event_ptr
;
301 event_queue
.first_event
= event_ptr
;
305 /* Create a file event, to be enqueued in the event queue for
306 processing. The procedure associated to this event is always
307 handle_file_event, which will in turn invoke the one that was
308 associated to FD when it was registered with the event loop. */
310 create_file_event (int fd
)
312 gdb_event
*file_event_ptr
;
314 file_event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
315 file_event_ptr
->proc
= handle_file_event
;
316 file_event_ptr
->fd
= fd
;
317 return (file_event_ptr
);
320 /* Process one event.
321 The event can be the next one to be serviced in the event queue,
322 or an asynchronous event handler can be invoked in response to
323 the reception of a signal.
324 If an event was processed (either way), 1 is returned otherwise
326 Scan the queue from head to tail, processing therefore the high
327 priority events first, by invoking the associated event handler
332 gdb_event
*event_ptr
, *prev_ptr
;
333 event_handler_func
*proc
;
336 /* First let's see if there are any asynchronous event handlers that
337 are ready. These would be the result of invoking any of the
340 if (check_async_ready ())
342 invoke_async_signal_handler ();
346 /* Look in the event queue to find an event that is ready
349 for (event_ptr
= event_queue
.first_event
; event_ptr
!= NULL
;
350 event_ptr
= event_ptr
->next_event
)
352 /* Call the handler for the event. */
354 proc
= event_ptr
->proc
;
357 /* Let's get rid of the event from the event queue. We need to
358 do this now because while processing the event, the proc
359 function could end up calling 'error' and therefore jump out
360 to the caller of this function, gdb_do_one_event. In that
361 case, we would have on the event queue an event wich has been
362 processed, but not deleted. */
364 if (event_queue
.first_event
== event_ptr
)
366 event_queue
.first_event
= event_ptr
->next_event
;
367 if (event_ptr
->next_event
== NULL
)
368 event_queue
.last_event
= NULL
;
372 prev_ptr
= event_queue
.first_event
;
373 while (prev_ptr
->next_event
!= event_ptr
)
374 prev_ptr
= prev_ptr
->next_event
;
376 prev_ptr
->next_event
= event_ptr
->next_event
;
377 if (event_ptr
->next_event
== NULL
)
378 event_queue
.last_event
= prev_ptr
;
382 /* Now call the procedure associated with the event. */
387 /* this is the case if there are no event on the event queue. */
391 /* Process one high level event. If nothing is ready at this time,
392 wait for something to happen (via gdb_wait_for_event), then process
393 it. Returns >0 if something was done otherwise returns <0 (this
394 can happen if there are no event sources to wait for). If an error
395 occurs catch_errors() which calls this function returns zero. */
398 gdb_do_one_event (void *data
)
400 /* Any events already waiting in the queue? */
401 if (process_event ())
406 /* Are any timers that are ready? If so, put an event on the queue. */
409 /* Wait for a new event. If gdb_wait_for_event returns -1,
410 we should get out because this means that there are no
411 event sources left. This will make the event loop stop,
412 and the application exit. */
414 if (gdb_wait_for_event () < 0)
419 /* Handle any new events occurred while waiting. */
420 if (process_event ())
425 /* If gdb_wait_for_event has returned 1, it means that one
426 event has been handled. We break out of the loop. */
430 /* Start up the event loop. This is the entry point to the event loop
431 from the command loop. */
434 start_event_loop (void)
436 /* Loop until there is nothing to do. This is the entry point to the
437 event loop engine. gdb_do_one_event, called via catch_errors()
438 will process one event for each invocation. It blocks waits for
439 an event and then processes it. >0 when an event is processed, 0
440 when catch_errors() caught an error and <0 when there are no
441 longer any event sources registered. */
444 int result
= catch_errors (gdb_do_one_event
, 0, "", RETURN_MASK_ALL
);
449 /* FIXME: this should really be a call to a hook that is
450 interface specific, because interfaces can display the
451 prompt in their own way. */
452 display_gdb_prompt (0);
453 /* Maybe better to set a flag to be checked somewhere as to
454 whether display the prompt or not. */
458 /* We are done with the event loop. There are no more event sources
459 to listen to. So we exit GDB. */
464 /* Wrapper function for create_file_handler, so that the caller
465 doesn't have to know implementation details about the use of poll
468 add_file_handler (int fd
, handler_func
* proc
, gdb_client_data client_data
)
477 /* Check to see if poll () is usable. If not, we'll switch to
478 use select. This can happen on systems like
479 m68k-motorola-sys, `poll' cannot be used to wait for `stdin'.
480 On m68k-motorola-sysv, tty's are not stream-based and not
484 if (poll (&fds
, 1, 0) == 1 && (fds
.revents
& POLLNVAL
))
487 internal_error (__FILE__
, __LINE__
,
488 "use_poll without HAVE_POLL");
489 #endif /* HAVE_POLL */
494 create_file_handler (fd
, POLLIN
, proc
, client_data
);
496 internal_error (__FILE__
, __LINE__
,
497 "use_poll without HAVE_POLL");
501 create_file_handler (fd
, GDB_READABLE
| GDB_EXCEPTION
, proc
, client_data
);
504 /* Add a file handler/descriptor to the list of descriptors we are
506 FD is the file descriptor for the file/stream to be listened to.
507 For the poll case, MASK is a combination (OR) of
508 POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM,
509 POLLWRBAND: these are the events we are interested in. If any of them
510 occurs, proc should be called.
511 For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION.
512 PROC is the procedure that will be called when an event occurs for
513 FD. CLIENT_DATA is the argument to pass to PROC. */
515 create_file_handler (int fd
, int mask
, handler_func
* proc
, gdb_client_data client_data
)
517 file_handler
*file_ptr
;
519 /* Do we already have a file handler for this file? (We may be
520 changing its associated procedure). */
521 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
522 file_ptr
= file_ptr
->next_file
)
524 if (file_ptr
->fd
== fd
)
528 /* It is a new file descriptor. Add it to the list. Otherwise, just
529 change the data associated with it. */
530 if (file_ptr
== NULL
)
532 file_ptr
= (file_handler
*) xmalloc (sizeof (file_handler
));
534 file_ptr
->ready_mask
= 0;
535 file_ptr
->next_file
= gdb_notifier
.first_file_handler
;
536 gdb_notifier
.first_file_handler
= file_ptr
;
538 file_ptr
->proc
= proc
;
539 file_ptr
->client_data
= client_data
;
540 file_ptr
->mask
= mask
;
545 gdb_notifier
.num_fds
++;
546 if (gdb_notifier
.poll_fds
)
547 gdb_notifier
.poll_fds
=
548 (struct pollfd
*) realloc (gdb_notifier
.poll_fds
,
549 (gdb_notifier
.num_fds
) * sizeof (struct pollfd
));
551 gdb_notifier
.poll_fds
=
552 (struct pollfd
*) xmalloc (sizeof (struct pollfd
));
553 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->fd
= fd
;
554 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->events
= mask
;
555 (gdb_notifier
.poll_fds
+ gdb_notifier
.num_fds
- 1)->revents
= 0;
557 internal_error (__FILE__
, __LINE__
,
558 "use_poll without HAVE_POLL");
559 #endif /* HAVE_POLL */
563 if (mask
& GDB_READABLE
)
564 FD_SET (fd
, &gdb_notifier
.check_masks
[0]);
566 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
568 if (mask
& GDB_WRITABLE
)
569 FD_SET (fd
, &gdb_notifier
.check_masks
[1]);
571 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
573 if (mask
& GDB_EXCEPTION
)
574 FD_SET (fd
, &gdb_notifier
.check_masks
[2]);
576 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
578 if (gdb_notifier
.num_fds
<= fd
)
579 gdb_notifier
.num_fds
= fd
+ 1;
583 /* Remove the file descriptor FD from the list of monitored fd's:
584 i.e. we don't care anymore about events on the FD. */
586 delete_file_handler (int fd
)
588 file_handler
*file_ptr
, *prev_ptr
= NULL
;
592 struct pollfd
*new_poll_fds
;
595 /* Find the entry for the given file. */
597 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
598 file_ptr
= file_ptr
->next_file
)
600 if (file_ptr
->fd
== fd
)
604 if (file_ptr
== NULL
)
610 /* Create a new poll_fds array by copying every fd's information but the
611 one we want to get rid of. */
614 (struct pollfd
*) xmalloc ((gdb_notifier
.num_fds
- 1) * sizeof (struct pollfd
));
616 for (i
= 0, j
= 0; i
< gdb_notifier
.num_fds
; i
++)
618 if ((gdb_notifier
.poll_fds
+ i
)->fd
!= fd
)
620 (new_poll_fds
+ j
)->fd
= (gdb_notifier
.poll_fds
+ i
)->fd
;
621 (new_poll_fds
+ j
)->events
= (gdb_notifier
.poll_fds
+ i
)->events
;
622 (new_poll_fds
+ j
)->revents
= (gdb_notifier
.poll_fds
+ i
)->revents
;
626 xfree (gdb_notifier
.poll_fds
);
627 gdb_notifier
.poll_fds
= new_poll_fds
;
628 gdb_notifier
.num_fds
--;
630 internal_error (__FILE__
, __LINE__
,
631 "use_poll without HAVE_POLL");
632 #endif /* HAVE_POLL */
636 if (file_ptr
->mask
& GDB_READABLE
)
637 FD_CLR (fd
, &gdb_notifier
.check_masks
[0]);
638 if (file_ptr
->mask
& GDB_WRITABLE
)
639 FD_CLR (fd
, &gdb_notifier
.check_masks
[1]);
640 if (file_ptr
->mask
& GDB_EXCEPTION
)
641 FD_CLR (fd
, &gdb_notifier
.check_masks
[2]);
643 /* Find current max fd. */
645 if ((fd
+ 1) == gdb_notifier
.num_fds
)
647 gdb_notifier
.num_fds
--;
648 for (i
= gdb_notifier
.num_fds
; i
; i
--)
650 if (FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[0])
651 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[1])
652 || FD_ISSET (i
- 1, &gdb_notifier
.check_masks
[2]))
655 gdb_notifier
.num_fds
= i
;
659 /* Deactivate the file descriptor, by clearing its mask,
660 so that it will not fire again. */
664 /* Get rid of the file handler in the file handler list. */
665 if (file_ptr
== gdb_notifier
.first_file_handler
)
666 gdb_notifier
.first_file_handler
= file_ptr
->next_file
;
669 for (prev_ptr
= gdb_notifier
.first_file_handler
;
670 prev_ptr
->next_file
!= file_ptr
;
671 prev_ptr
= prev_ptr
->next_file
)
673 prev_ptr
->next_file
= file_ptr
->next_file
;
678 /* Handle the given event by calling the procedure associated to the
679 corresponding file handler. Called by process_event indirectly,
680 through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the
681 event in the front of the event queue. */
683 handle_file_event (int event_file_desc
)
685 file_handler
*file_ptr
;
689 int error_mask_returned
;
692 /* Search the file handler list to find one that matches the fd in
694 for (file_ptr
= gdb_notifier
.first_file_handler
; file_ptr
!= NULL
;
695 file_ptr
= file_ptr
->next_file
)
697 if (file_ptr
->fd
== event_file_desc
)
699 /* With poll, the ready_mask could have any of three events
700 set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot
701 be used in the requested event mask (events), but they
702 can be returned in the return mask (revents). We need to
703 check for those event too, and add them to the mask which
704 will be passed to the handler. */
706 /* See if the desired events (mask) match the received
707 events (ready_mask). */
712 error_mask
= POLLHUP
| POLLERR
| POLLNVAL
;
713 mask
= (file_ptr
->ready_mask
& file_ptr
->mask
) |
714 (file_ptr
->ready_mask
& error_mask
);
715 error_mask_returned
= mask
& error_mask
;
717 if (error_mask_returned
!= 0)
719 /* Work in progress. We may need to tell somebody what
720 kind of error we had. */
721 if (error_mask_returned
& POLLHUP
)
722 printf_unfiltered ("Hangup detected on fd %d\n", file_ptr
->fd
);
723 if (error_mask_returned
& POLLERR
)
724 printf_unfiltered ("Error detected on fd %d\n", file_ptr
->fd
);
725 if (error_mask_returned
& POLLNVAL
)
726 printf_unfiltered ("Invalid or non-`poll'able fd %d\n", file_ptr
->fd
);
732 internal_error (__FILE__
, __LINE__
,
733 "use_poll without HAVE_POLL");
734 #endif /* HAVE_POLL */
738 if (file_ptr
->ready_mask
& GDB_EXCEPTION
)
740 printf_unfiltered ("Exception condition detected on fd %d\n", file_ptr
->fd
);
745 mask
= file_ptr
->ready_mask
& file_ptr
->mask
;
748 /* Clear the received events for next time around. */
749 file_ptr
->ready_mask
= 0;
751 /* If there was a match, then call the handler. */
753 (*file_ptr
->proc
) (file_ptr
->error
, file_ptr
->client_data
);
759 /* Called by gdb_do_one_event to wait for new events on the
760 monitored file descriptors. Queue file events as they are
761 detected by the poll.
762 If there are no events, this function will block in the
764 Return -1 if there are no files descriptors to monitor,
765 otherwise return 0. */
767 gdb_wait_for_event (void)
769 file_handler
*file_ptr
;
770 gdb_event
*file_event_ptr
;
774 /* Make sure all output is done before getting another event. */
775 gdb_flush (gdb_stdout
);
776 gdb_flush (gdb_stderr
);
778 if (gdb_notifier
.num_fds
== 0)
785 poll (gdb_notifier
.poll_fds
,
786 (unsigned long) gdb_notifier
.num_fds
,
787 gdb_notifier
.timeout_valid
? gdb_notifier
.poll_timeout
: -1);
789 /* Don't print anything if we get out of poll because of a
791 if (num_found
== -1 && errno
!= EINTR
)
792 perror_with_name ("Poll");
794 internal_error (__FILE__
, __LINE__
,
795 "use_poll without HAVE_POLL");
796 #endif /* HAVE_POLL */
800 gdb_notifier
.ready_masks
[0] = gdb_notifier
.check_masks
[0];
801 gdb_notifier
.ready_masks
[1] = gdb_notifier
.check_masks
[1];
802 gdb_notifier
.ready_masks
[2] = gdb_notifier
.check_masks
[2];
803 num_found
= select (gdb_notifier
.num_fds
,
804 &gdb_notifier
.ready_masks
[0],
805 &gdb_notifier
.ready_masks
[1],
806 &gdb_notifier
.ready_masks
[2],
807 gdb_notifier
.timeout_valid
808 ? &gdb_notifier
.select_timeout
: NULL
);
810 /* Clear the masks after an error from select. */
813 FD_ZERO (&gdb_notifier
.ready_masks
[0]);
814 FD_ZERO (&gdb_notifier
.ready_masks
[1]);
815 FD_ZERO (&gdb_notifier
.ready_masks
[2]);
816 /* Dont print anything is we got a signal, let gdb handle it. */
818 perror_with_name ("Select");
822 /* Enqueue all detected file events. */
827 for (i
= 0; (i
< gdb_notifier
.num_fds
) && (num_found
> 0); i
++)
829 if ((gdb_notifier
.poll_fds
+ i
)->revents
)
834 for (file_ptr
= gdb_notifier
.first_file_handler
;
836 file_ptr
= file_ptr
->next_file
)
838 if (file_ptr
->fd
== (gdb_notifier
.poll_fds
+ i
)->fd
)
844 /* Enqueue an event only if this is still a new event for
846 if (file_ptr
->ready_mask
== 0)
848 file_event_ptr
= create_file_event (file_ptr
->fd
);
849 async_queue_event (file_event_ptr
, TAIL
);
853 file_ptr
->ready_mask
= (gdb_notifier
.poll_fds
+ i
)->revents
;
856 internal_error (__FILE__
, __LINE__
,
857 "use_poll without HAVE_POLL");
858 #endif /* HAVE_POLL */
862 for (file_ptr
= gdb_notifier
.first_file_handler
;
863 (file_ptr
!= NULL
) && (num_found
> 0);
864 file_ptr
= file_ptr
->next_file
)
868 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[0]))
869 mask
|= GDB_READABLE
;
870 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[1]))
871 mask
|= GDB_WRITABLE
;
872 if (FD_ISSET (file_ptr
->fd
, &gdb_notifier
.ready_masks
[2]))
873 mask
|= GDB_EXCEPTION
;
880 /* Enqueue an event only if this is still a new event for
883 if (file_ptr
->ready_mask
== 0)
885 file_event_ptr
= create_file_event (file_ptr
->fd
);
886 async_queue_event (file_event_ptr
, TAIL
);
888 file_ptr
->ready_mask
= mask
;
895 /* Create an asynchronous handler, allocating memory for it.
896 Return a pointer to the newly created handler.
897 This pointer will be used to invoke the handler by
898 invoke_async_signal_handler.
899 PROC is the function to call with CLIENT_DATA argument
900 whenever the handler is invoked. */
901 async_signal_handler
*
902 create_async_signal_handler (sig_handler_func
* proc
, gdb_client_data client_data
)
904 async_signal_handler
*async_handler_ptr
;
907 (async_signal_handler
*) xmalloc (sizeof (async_signal_handler
));
908 async_handler_ptr
->ready
= 0;
909 async_handler_ptr
->next_handler
= NULL
;
910 async_handler_ptr
->proc
= proc
;
911 async_handler_ptr
->client_data
= client_data
;
912 if (sighandler_list
.first_handler
== NULL
)
913 sighandler_list
.first_handler
= async_handler_ptr
;
915 sighandler_list
.last_handler
->next_handler
= async_handler_ptr
;
916 sighandler_list
.last_handler
= async_handler_ptr
;
917 return async_handler_ptr
;
920 /* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will
921 be used when the handlers are invoked, after we have waited for
922 some event. The caller of this function is the interrupt handler
923 associated with a signal. */
925 mark_async_signal_handler (async_signal_handler
* async_handler_ptr
)
927 ((async_signal_handler
*) async_handler_ptr
)->ready
= 1;
928 async_handler_ready
= 1;
931 /* Call all the handlers that are ready. */
933 invoke_async_signal_handler (void)
935 async_signal_handler
*async_handler_ptr
;
937 if (async_handler_ready
== 0)
939 async_handler_ready
= 0;
941 /* Invoke ready handlers. */
945 for (async_handler_ptr
= sighandler_list
.first_handler
;
946 async_handler_ptr
!= NULL
;
947 async_handler_ptr
= async_handler_ptr
->next_handler
)
949 if (async_handler_ptr
->ready
)
952 if (async_handler_ptr
== NULL
)
954 async_handler_ptr
->ready
= 0;
955 (*async_handler_ptr
->proc
) (async_handler_ptr
->client_data
);
961 /* Delete an asynchronous handler (ASYNC_HANDLER_PTR).
962 Free the space allocated for it. */
964 delete_async_signal_handler (async_signal_handler
** async_handler_ptr
)
966 async_signal_handler
*prev_ptr
;
968 if (sighandler_list
.first_handler
== (*async_handler_ptr
))
970 sighandler_list
.first_handler
= (*async_handler_ptr
)->next_handler
;
971 if (sighandler_list
.first_handler
== NULL
)
972 sighandler_list
.last_handler
= NULL
;
976 prev_ptr
= sighandler_list
.first_handler
;
977 while (prev_ptr
->next_handler
!= (*async_handler_ptr
) && prev_ptr
)
978 prev_ptr
= prev_ptr
->next_handler
;
979 prev_ptr
->next_handler
= (*async_handler_ptr
)->next_handler
;
980 if (sighandler_list
.last_handler
== (*async_handler_ptr
))
981 sighandler_list
.last_handler
= prev_ptr
;
983 xfree ((*async_handler_ptr
));
984 (*async_handler_ptr
) = NULL
;
987 /* Is it necessary to call invoke_async_signal_handler? */
989 check_async_ready (void)
991 return async_handler_ready
;
994 /* Create a timer that will expire in MILLISECONDS from now. When the
995 timer is ready, PROC will be executed. At creation, the timer is
996 aded to the timers queue. This queue is kept sorted in order of
997 increasing timers. Return a handle to the timer struct. */
999 create_timer (int milliseconds
, timer_handler_func
* proc
, gdb_client_data client_data
)
1001 struct gdb_timer
*timer_ptr
, *timer_index
, *prev_timer
;
1002 struct timeval time_now
, delta
;
1004 /* compute seconds */
1005 delta
.tv_sec
= milliseconds
/ 1000;
1006 /* compute microseconds */
1007 delta
.tv_usec
= (milliseconds
% 1000) * 1000;
1009 gettimeofday (&time_now
, NULL
);
1011 timer_ptr
= (struct gdb_timer
*) xmalloc (sizeof (gdb_timer
));
1012 timer_ptr
->when
.tv_sec
= time_now
.tv_sec
+ delta
.tv_sec
;
1013 timer_ptr
->when
.tv_usec
= time_now
.tv_usec
+ delta
.tv_usec
;
1015 if (timer_ptr
->when
.tv_usec
>= 1000000)
1017 timer_ptr
->when
.tv_sec
+= 1;
1018 timer_ptr
->when
.tv_usec
-= 1000000;
1020 timer_ptr
->proc
= proc
;
1021 timer_ptr
->client_data
= client_data
;
1022 timer_list
.num_timers
++;
1023 timer_ptr
->timer_id
= timer_list
.num_timers
;
1025 /* Now add the timer to the timer queue, making sure it is sorted in
1026 increasing order of expiration. */
1028 for (timer_index
= timer_list
.first_timer
;
1029 timer_index
!= NULL
;
1030 timer_index
= timer_index
->next
)
1032 /* If the seconds field is greater or if it is the same, but the
1033 microsecond field is greater. */
1034 if ((timer_index
->when
.tv_sec
> timer_ptr
->when
.tv_sec
) ||
1035 ((timer_index
->when
.tv_sec
== timer_ptr
->when
.tv_sec
)
1036 && (timer_index
->when
.tv_usec
> timer_ptr
->when
.tv_usec
)))
1040 if (timer_index
== timer_list
.first_timer
)
1042 timer_ptr
->next
= timer_list
.first_timer
;
1043 timer_list
.first_timer
= timer_ptr
;
1048 for (prev_timer
= timer_list
.first_timer
;
1049 prev_timer
->next
!= timer_index
;
1050 prev_timer
= prev_timer
->next
)
1053 prev_timer
->next
= timer_ptr
;
1054 timer_ptr
->next
= timer_index
;
1057 gdb_notifier
.timeout_valid
= 0;
1058 return timer_ptr
->timer_id
;
1061 /* There is a chance that the creator of the timer wants to get rid of
1062 it before it expires. */
1064 delete_timer (int id
)
1066 struct gdb_timer
*timer_ptr
, *prev_timer
= NULL
;
1068 /* Find the entry for the given timer. */
1070 for (timer_ptr
= timer_list
.first_timer
; timer_ptr
!= NULL
;
1071 timer_ptr
= timer_ptr
->next
)
1073 if (timer_ptr
->timer_id
== id
)
1077 if (timer_ptr
== NULL
)
1079 /* Get rid of the timer in the timer list. */
1080 if (timer_ptr
== timer_list
.first_timer
)
1081 timer_list
.first_timer
= timer_ptr
->next
;
1084 for (prev_timer
= timer_list
.first_timer
;
1085 prev_timer
->next
!= timer_ptr
;
1086 prev_timer
= prev_timer
->next
)
1088 prev_timer
->next
= timer_ptr
->next
;
1092 gdb_notifier
.timeout_valid
= 0;
1095 /* When a timer event is put on the event queue, it will be handled by
1096 this function. Just call the assiciated procedure and delete the
1097 timer event from the event queue. Repeat this for each timer that
1100 handle_timer_event (int dummy
)
1102 struct timeval time_now
;
1103 struct gdb_timer
*timer_ptr
, *saved_timer
;
1105 gettimeofday (&time_now
, NULL
);
1106 timer_ptr
= timer_list
.first_timer
;
1108 while (timer_ptr
!= NULL
)
1110 if ((timer_ptr
->when
.tv_sec
> time_now
.tv_sec
) ||
1111 ((timer_ptr
->when
.tv_sec
== time_now
.tv_sec
) &&
1112 (timer_ptr
->when
.tv_usec
> time_now
.tv_usec
)))
1115 /* Get rid of the timer from the beginning of the list. */
1116 timer_list
.first_timer
= timer_ptr
->next
;
1117 saved_timer
= timer_ptr
;
1118 timer_ptr
= timer_ptr
->next
;
1119 /* Call the procedure associated with that timer. */
1120 (*saved_timer
->proc
) (saved_timer
->client_data
);
1121 xfree (saved_timer
);
1124 gdb_notifier
.timeout_valid
= 0;
1127 /* Check whether any timers in the timers queue are ready. If at least
1128 one timer is ready, stick an event onto the event queue. Even in
1129 case more than one timer is ready, one event is enough, because the
1130 handle_timer_event() will go through the timers list and call the
1131 procedures associated with all that have expired. Update the
1132 timeout for the select() or poll() as well. */
1136 struct timeval time_now
, delta
;
1137 gdb_event
*event_ptr
;
1139 if (timer_list
.first_timer
!= NULL
)
1141 gettimeofday (&time_now
, NULL
);
1142 delta
.tv_sec
= timer_list
.first_timer
->when
.tv_sec
- time_now
.tv_sec
;
1143 delta
.tv_usec
= timer_list
.first_timer
->when
.tv_usec
- time_now
.tv_usec
;
1145 if (delta
.tv_usec
< 0)
1148 delta
.tv_usec
+= 1000000;
1151 /* Oops it expired already. Tell select / poll to return
1152 immediately. (Cannot simply test if delta.tv_sec is negative
1153 because time_t might be unsigned.) */
1154 if (timer_list
.first_timer
->when
.tv_sec
< time_now
.tv_sec
1155 || (timer_list
.first_timer
->when
.tv_sec
== time_now
.tv_sec
1156 && timer_list
.first_timer
->when
.tv_usec
< time_now
.tv_usec
))
1162 if (delta
.tv_sec
== 0 && delta
.tv_usec
== 0)
1164 event_ptr
= (gdb_event
*) xmalloc (sizeof (gdb_event
));
1165 event_ptr
->proc
= handle_timer_event
;
1166 event_ptr
->fd
= timer_list
.first_timer
->timer_id
;
1167 async_queue_event (event_ptr
, TAIL
);
1170 /* Now we need to update the timeout for select/ poll, because we
1171 don't want to sit there while this timer is expiring. */
1175 gdb_notifier
.poll_timeout
= delta
.tv_sec
* 1000;
1177 internal_error (__FILE__
, __LINE__
,
1178 "use_poll without HAVE_POLL");
1179 #endif /* HAVE_POLL */
1183 gdb_notifier
.select_timeout
.tv_sec
= delta
.tv_sec
;
1184 gdb_notifier
.select_timeout
.tv_usec
= delta
.tv_usec
;
1186 gdb_notifier
.timeout_valid
= 1;
1189 gdb_notifier
.timeout_valid
= 0;