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Diffstat (limited to 'gdb/event-loop.c')
| -rw-r--r-- | gdb/event-loop.c | 1151 |
1 files changed, 0 insertions, 1151 deletions
diff --git a/gdb/event-loop.c b/gdb/event-loop.c deleted file mode 100644 index ea74419623e..00000000000 --- a/gdb/event-loop.c +++ /dev/null @@ -1,1151 +0,0 @@ -/* Event loop machinery for GDB, the GNU debugger. - Copyright 1999, 2000, 2001 Free Software Foundation, Inc. - Written by Elena Zannoni <ezannoni@cygnus.com> of Cygnus Solutions. - - This file is part of GDB. - - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place - Suite 330, - Boston, MA 02111-1307, USA. */ - -#include "defs.h" -#include "event-loop.h" -#include "event-top.h" - -#ifdef HAVE_POLL -#if defined (HAVE_POLL_H) -#include <poll.h> -#elif defined (HAVE_SYS_POLL_H) -#include <sys/poll.h> -#endif -#endif - -#include <sys/types.h> -#include "gdb_string.h" -#include <errno.h> -#include <sys/time.h> - -typedef struct gdb_event gdb_event; -typedef void (event_handler_func) (int); - -/* Event for the GDB event system. Events are queued by calling - async_queue_event and serviced later on by gdb_do_one_event. An - event can be, for instance, a file descriptor becoming ready to be - read. Servicing an event simply means that the procedure PROC will - be called. We have 2 queues, one for file handlers that we listen - to in the event loop, and one for the file handlers+events that are - ready. The procedure PROC associated with each event is always the - same (handle_file_event). Its duty is to invoke the handler - associated with the file descriptor whose state change generated - the event, plus doing other cleanups and such. */ - -struct gdb_event - { - event_handler_func *proc; /* Procedure to call to service this event. */ - int fd; /* File descriptor that is ready. */ - struct gdb_event *next_event; /* Next in list of events or NULL. */ - }; - -/* Information about each file descriptor we register with the event - loop. */ - -typedef struct file_handler - { - int fd; /* File descriptor. */ - int mask; /* Events we want to monitor: POLLIN, etc. */ - int ready_mask; /* Events that have been seen since - the last time. */ - handler_func *proc; /* Procedure to call when fd is ready. */ - gdb_client_data client_data; /* Argument to pass to proc. */ - int error; /* Was an error detected on this fd? */ - struct file_handler *next_file; /* Next registered file descriptor. */ - } -file_handler; - -/* PROC is a function to be invoked when the READY flag is set. This - happens when there has been a signal and the corresponding signal - handler has 'triggered' this async_signal_handler for - execution. The actual work to be done in response to a signal will - be carried out by PROC at a later time, within process_event. This - provides a deferred execution of signal handlers. - Async_init_signals takes care of setting up such an - asyn_signal_handler for each interesting signal. */ -typedef struct async_signal_handler - { - int ready; /* If ready, call this handler from the main event loop, - using invoke_async_handler. */ - struct async_signal_handler *next_handler; /* Ptr to next handler */ - sig_handler_func *proc; /* Function to call to do the work */ - gdb_client_data client_data; /* Argument to async_handler_func */ - } -async_signal_handler; - - -/* Event queue: - - the first event in the queue is the head of the queue. - It will be the next to be serviced. - - the last event in the queue - - Events can be inserted at the front of the queue or at the end of - the queue. Events will be extracted from the queue for processing - starting from the head. Therefore, events inserted at the head of - the queue will be processed in a last in first out fashion, while - those inserted at the tail of the queue will be processed in a first - in first out manner. All the fields are NULL if the queue is - empty. */ - -static struct - { - gdb_event *first_event; /* First pending event */ - gdb_event *last_event; /* Last pending event */ - } -event_queue; - -/* Gdb_notifier is just a list of file descriptors gdb is interested in. - These are the input file descriptor, and the target file - descriptor. We have two flavors of the notifier, one for platforms - that have the POLL function, the other for those that don't, and - only support SELECT. Each of the elements in the gdb_notifier list is - basically a description of what kind of events gdb is interested - in, for each fd. */ - -/* As of 1999-04-30 only the input file descriptor is registered with the - event loop. */ - -/* Do we use poll or select ? */ -#ifdef HAVE_POLL -#define USE_POLL 1 -#else -#define USE_POLL 0 -#endif /* HAVE_POLL */ - -static unsigned char use_poll = USE_POLL; - -static struct - { - /* Ptr to head of file handler list. */ - file_handler *first_file_handler; - -#ifdef HAVE_POLL - /* Ptr to array of pollfd structures. */ - struct pollfd *poll_fds; - - /* Timeout in milliseconds for calls to poll(). */ - int poll_timeout; -#endif - - /* Masks to be used in the next call to select. - Bits are set in response to calls to create_file_handler. */ - fd_set check_masks[3]; - - /* What file descriptors were found ready by select. */ - fd_set ready_masks[3]; - - /* Number of file descriptors to monitor. (for poll) */ - /* Number of valid bits (highest fd value + 1). (for select) */ - int num_fds; - - /* Time structure for calls to select(). */ - struct timeval select_timeout; - - /* Flag to tell whether the timeout should be used. */ - int timeout_valid; - } -gdb_notifier; - -/* Structure associated with a timer. PROC will be executed at the - first occasion after WHEN. */ -struct gdb_timer - { - struct timeval when; - int timer_id; - struct gdb_timer *next; - timer_handler_func *proc; /* Function to call to do the work */ - gdb_client_data client_data; /* Argument to async_handler_func */ - } -gdb_timer; - -/* List of currently active timers. It is sorted in order of - increasing timers. */ -static struct - { - /* Pointer to first in timer list. */ - struct gdb_timer *first_timer; - - /* Id of the last timer created. */ - int num_timers; - } -timer_list; - -/* All the async_signal_handlers gdb is interested in are kept onto - this list. */ -static struct - { - /* Pointer to first in handler list. */ - async_signal_handler *first_handler; - - /* Pointer to last in handler list. */ - async_signal_handler *last_handler; - } -sighandler_list; - -/* Are any of the handlers ready? Check this variable using - check_async_ready. This is used by process_event, to determine - whether or not to invoke the invoke_async_signal_handler - function. */ -static int async_handler_ready = 0; - -static void create_file_handler (int fd, int mask, handler_func * proc, gdb_client_data client_data); -static void invoke_async_signal_handler (void); -static void handle_file_event (int event_file_desc); -static int gdb_wait_for_event (void); -static int gdb_do_one_event (void *data); -static int check_async_ready (void); -static void async_queue_event (gdb_event * event_ptr, queue_position position); -static gdb_event *create_file_event (int fd); -static int process_event (void); -static void handle_timer_event (int dummy); -static void poll_timers (void); - - -/* Insert an event object into the gdb event queue at - the specified position. - POSITION can be head or tail, with values TAIL, HEAD. - EVENT_PTR points to the event to be inserted into the queue. - The caller must allocate memory for the event. It is freed - after the event has ben handled. - Events in the queue will be processed head to tail, therefore, - events inserted at the head of the queue will be processed - as last in first out. Event appended at the tail of the queue - will be processed first in first out. */ -static void -async_queue_event (gdb_event * event_ptr, queue_position position) -{ - if (position == TAIL) - { - /* The event will become the new last_event. */ - - event_ptr->next_event = NULL; - if (event_queue.first_event == NULL) - event_queue.first_event = event_ptr; - else - event_queue.last_event->next_event = event_ptr; - event_queue.last_event = event_ptr; - } - else if (position == HEAD) - { - /* The event becomes the new first_event. */ - - event_ptr->next_event = event_queue.first_event; - if (event_queue.first_event == NULL) - event_queue.last_event = event_ptr; - event_queue.first_event = event_ptr; - } -} - -/* Create a file event, to be enqueued in the event queue for - processing. The procedure associated to this event is always - handle_file_event, which will in turn invoke the one that was - associated to FD when it was registered with the event loop. */ -static gdb_event * -create_file_event (int fd) -{ - gdb_event *file_event_ptr; - - file_event_ptr = (gdb_event *) xmalloc (sizeof (gdb_event)); - file_event_ptr->proc = handle_file_event; - file_event_ptr->fd = fd; - return (file_event_ptr); -} - -/* Process one event. - The event can be the next one to be serviced in the event queue, - or an asynchronous event handler can be invoked in response to - the reception of a signal. - If an event was processed (either way), 1 is returned otherwise - 0 is returned. - Scan the queue from head to tail, processing therefore the high - priority events first, by invoking the associated event handler - procedure. */ -static int -process_event (void) -{ - gdb_event *event_ptr, *prev_ptr; - event_handler_func *proc; - int fd; - - /* First let's see if there are any asynchronous event handlers that - are ready. These would be the result of invoking any of the - signal handlers. */ - - if (check_async_ready ()) - { - invoke_async_signal_handler (); - return 1; - } - - /* Look in the event queue to find an event that is ready - to be processed. */ - - for (event_ptr = event_queue.first_event; event_ptr != NULL; - event_ptr = event_ptr->next_event) - { - /* Call the handler for the event. */ - - proc = event_ptr->proc; - fd = event_ptr->fd; - - /* Let's get rid of the event from the event queue. We need to - do this now because while processing the event, the proc - function could end up calling 'error' and therefore jump out - to the caller of this function, gdb_do_one_event. In that - case, we would have on the event queue an event wich has been - processed, but not deleted. */ - - if (event_queue.first_event == event_ptr) - { - event_queue.first_event = event_ptr->next_event; - if (event_ptr->next_event == NULL) - event_queue.last_event = NULL; - } - else - { - prev_ptr = event_queue.first_event; - while (prev_ptr->next_event != event_ptr) - prev_ptr = prev_ptr->next_event; - - prev_ptr->next_event = event_ptr->next_event; - if (event_ptr->next_event == NULL) - event_queue.last_event = prev_ptr; - } - xfree (event_ptr); - - /* Now call the procedure associated with the event. */ - (*proc) (fd); - return 1; - } - - /* this is the case if there are no event on the event queue. */ - return 0; -} - -/* Process one high level event. If nothing is ready at this time, - wait for something to happen (via gdb_wait_for_event), then process - it. Returns >0 if something was done otherwise returns <0 (this - can happen if there are no event sources to wait for). If an error - occurs catch_errors() which calls this function returns zero. */ - -static int -gdb_do_one_event (void *data) -{ - /* Any events already waiting in the queue? */ - if (process_event ()) - { - return 1; - } - - /* Are any timers that are ready? If so, put an event on the queue. */ - poll_timers (); - - /* Wait for a new event. If gdb_wait_for_event returns -1, - we should get out because this means that there are no - event sources left. This will make the event loop stop, - and the application exit. */ - - if (gdb_wait_for_event () < 0) - { - return -1; - } - - /* Handle any new events occurred while waiting. */ - if (process_event ()) - { - return 1; - } - - /* If gdb_wait_for_event has returned 1, it means that one - event has been handled. We break out of the loop. */ - return 1; -} - -/* Start up the event loop. This is the entry point to the event loop - from the command loop. */ - -void -start_event_loop (void) -{ - /* Loop until there is nothing to do. This is the entry point to the - event loop engine. gdb_do_one_event, called via catch_errors() - will process one event for each invocation. It blocks waits for - an event and then processes it. >0 when an event is processed, 0 - when catch_errors() caught an error and <0 when there are no - longer any event sources registered. */ - while (1) - { - int result = catch_errors (gdb_do_one_event, 0, "", RETURN_MASK_ALL); - if (result < 0) - break; - if (result == 0) - { - /* FIXME: this should really be a call to a hook that is - interface specific, because interfaces can display the - prompt in their own way. */ - display_gdb_prompt (0); - /* This call looks bizarre, but it is required. If the user - entered a command that caused an error, - after_char_processing_hook won't be called from - rl_callback_read_char_wrapper. Using a cleanup there - won't work, since we want this function to be called - after a new prompt is printed. */ - if (after_char_processing_hook) - (*after_char_processing_hook) (); - /* Maybe better to set a flag to be checked somewhere as to - whether display the prompt or not. */ - } - } - - /* We are done with the event loop. There are no more event sources - to listen to. So we exit GDB. */ - return; -} - - -/* Wrapper function for create_file_handler, so that the caller - doesn't have to know implementation details about the use of poll - vs. select. */ -void -add_file_handler (int fd, handler_func * proc, gdb_client_data client_data) -{ -#ifdef HAVE_POLL - struct pollfd fds; -#endif - - if (use_poll) - { -#ifdef HAVE_POLL - /* Check to see if poll () is usable. If not, we'll switch to - use select. This can happen on systems like - m68k-motorola-sys, `poll' cannot be used to wait for `stdin'. - On m68k-motorola-sysv, tty's are not stream-based and not - `poll'able. */ - fds.fd = fd; - fds.events = POLLIN; - if (poll (&fds, 1, 0) == 1 && (fds.revents & POLLNVAL)) - use_poll = 0; -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - if (use_poll) - { -#ifdef HAVE_POLL - create_file_handler (fd, POLLIN, proc, client_data); -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif - } - else - create_file_handler (fd, GDB_READABLE | GDB_EXCEPTION, proc, client_data); -} - -/* Add a file handler/descriptor to the list of descriptors we are - interested in. - FD is the file descriptor for the file/stream to be listened to. - For the poll case, MASK is a combination (OR) of - POLLIN, POLLRDNORM, POLLRDBAND, POLLPRI, POLLOUT, POLLWRNORM, - POLLWRBAND: these are the events we are interested in. If any of them - occurs, proc should be called. - For the select case, MASK is a combination of READABLE, WRITABLE, EXCEPTION. - PROC is the procedure that will be called when an event occurs for - FD. CLIENT_DATA is the argument to pass to PROC. */ -static void -create_file_handler (int fd, int mask, handler_func * proc, gdb_client_data client_data) -{ - file_handler *file_ptr; - - /* Do we already have a file handler for this file? (We may be - changing its associated procedure). */ - for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; - file_ptr = file_ptr->next_file) - { - if (file_ptr->fd == fd) - break; - } - - /* It is a new file descriptor. Add it to the list. Otherwise, just - change the data associated with it. */ - if (file_ptr == NULL) - { - file_ptr = (file_handler *) xmalloc (sizeof (file_handler)); - file_ptr->fd = fd; - file_ptr->ready_mask = 0; - file_ptr->next_file = gdb_notifier.first_file_handler; - gdb_notifier.first_file_handler = file_ptr; - } - file_ptr->proc = proc; - file_ptr->client_data = client_data; - file_ptr->mask = mask; - - if (use_poll) - { -#ifdef HAVE_POLL - gdb_notifier.num_fds++; - if (gdb_notifier.poll_fds) - gdb_notifier.poll_fds = - (struct pollfd *) xrealloc (gdb_notifier.poll_fds, - (gdb_notifier.num_fds - * sizeof (struct pollfd))); - else - gdb_notifier.poll_fds = - (struct pollfd *) xmalloc (sizeof (struct pollfd)); - (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->fd = fd; - (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->events = mask; - (gdb_notifier.poll_fds + gdb_notifier.num_fds - 1)->revents = 0; -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - if (mask & GDB_READABLE) - FD_SET (fd, &gdb_notifier.check_masks[0]); - else - FD_CLR (fd, &gdb_notifier.check_masks[0]); - - if (mask & GDB_WRITABLE) - FD_SET (fd, &gdb_notifier.check_masks[1]); - else - FD_CLR (fd, &gdb_notifier.check_masks[1]); - - if (mask & GDB_EXCEPTION) - FD_SET (fd, &gdb_notifier.check_masks[2]); - else - FD_CLR (fd, &gdb_notifier.check_masks[2]); - - if (gdb_notifier.num_fds <= fd) - gdb_notifier.num_fds = fd + 1; - } -} - -/* Remove the file descriptor FD from the list of monitored fd's: - i.e. we don't care anymore about events on the FD. */ -void -delete_file_handler (int fd) -{ - file_handler *file_ptr, *prev_ptr = NULL; - int i; -#ifdef HAVE_POLL - int j; - struct pollfd *new_poll_fds; -#endif - - /* Find the entry for the given file. */ - - for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; - file_ptr = file_ptr->next_file) - { - if (file_ptr->fd == fd) - break; - } - - if (file_ptr == NULL) - return; - - if (use_poll) - { -#ifdef HAVE_POLL - /* Create a new poll_fds array by copying every fd's information but the - one we want to get rid of. */ - - new_poll_fds = - (struct pollfd *) xmalloc ((gdb_notifier.num_fds - 1) * sizeof (struct pollfd)); - - for (i = 0, j = 0; i < gdb_notifier.num_fds; i++) - { - if ((gdb_notifier.poll_fds + i)->fd != fd) - { - (new_poll_fds + j)->fd = (gdb_notifier.poll_fds + i)->fd; - (new_poll_fds + j)->events = (gdb_notifier.poll_fds + i)->events; - (new_poll_fds + j)->revents = (gdb_notifier.poll_fds + i)->revents; - j++; - } - } - xfree (gdb_notifier.poll_fds); - gdb_notifier.poll_fds = new_poll_fds; - gdb_notifier.num_fds--; -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - if (file_ptr->mask & GDB_READABLE) - FD_CLR (fd, &gdb_notifier.check_masks[0]); - if (file_ptr->mask & GDB_WRITABLE) - FD_CLR (fd, &gdb_notifier.check_masks[1]); - if (file_ptr->mask & GDB_EXCEPTION) - FD_CLR (fd, &gdb_notifier.check_masks[2]); - - /* Find current max fd. */ - - if ((fd + 1) == gdb_notifier.num_fds) - { - gdb_notifier.num_fds--; - for (i = gdb_notifier.num_fds; i; i--) - { - if (FD_ISSET (i - 1, &gdb_notifier.check_masks[0]) - || FD_ISSET (i - 1, &gdb_notifier.check_masks[1]) - || FD_ISSET (i - 1, &gdb_notifier.check_masks[2])) - break; - } - gdb_notifier.num_fds = i; - } - } - - /* Deactivate the file descriptor, by clearing its mask, - so that it will not fire again. */ - - file_ptr->mask = 0; - - /* Get rid of the file handler in the file handler list. */ - if (file_ptr == gdb_notifier.first_file_handler) - gdb_notifier.first_file_handler = file_ptr->next_file; - else - { - for (prev_ptr = gdb_notifier.first_file_handler; - prev_ptr->next_file != file_ptr; - prev_ptr = prev_ptr->next_file) - ; - prev_ptr->next_file = file_ptr->next_file; - } - xfree (file_ptr); -} - -/* Handle the given event by calling the procedure associated to the - corresponding file handler. Called by process_event indirectly, - through event_ptr->proc. EVENT_FILE_DESC is file descriptor of the - event in the front of the event queue. */ -static void -handle_file_event (int event_file_desc) -{ - file_handler *file_ptr; - int mask; -#ifdef HAVE_POLL - int error_mask; - int error_mask_returned; -#endif - - /* Search the file handler list to find one that matches the fd in - the event. */ - for (file_ptr = gdb_notifier.first_file_handler; file_ptr != NULL; - file_ptr = file_ptr->next_file) - { - if (file_ptr->fd == event_file_desc) - { - /* With poll, the ready_mask could have any of three events - set to 1: POLLHUP, POLLERR, POLLNVAL. These events cannot - be used in the requested event mask (events), but they - can be returned in the return mask (revents). We need to - check for those event too, and add them to the mask which - will be passed to the handler. */ - - /* See if the desired events (mask) match the received - events (ready_mask). */ - - if (use_poll) - { -#ifdef HAVE_POLL - error_mask = POLLHUP | POLLERR | POLLNVAL; - mask = (file_ptr->ready_mask & file_ptr->mask) | - (file_ptr->ready_mask & error_mask); - error_mask_returned = mask & error_mask; - - if (error_mask_returned != 0) - { - /* Work in progress. We may need to tell somebody what - kind of error we had. */ - if (error_mask_returned & POLLHUP) - printf_unfiltered ("Hangup detected on fd %d\n", file_ptr->fd); - if (error_mask_returned & POLLERR) - printf_unfiltered ("Error detected on fd %d\n", file_ptr->fd); - if (error_mask_returned & POLLNVAL) - printf_unfiltered ("Invalid or non-`poll'able fd %d\n", file_ptr->fd); - file_ptr->error = 1; - } - else - file_ptr->error = 0; -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - if (file_ptr->ready_mask & GDB_EXCEPTION) - { - printf_unfiltered ("Exception condition detected on fd %d\n", file_ptr->fd); - file_ptr->error = 1; - } - else - file_ptr->error = 0; - mask = file_ptr->ready_mask & file_ptr->mask; - } - - /* Clear the received events for next time around. */ - file_ptr->ready_mask = 0; - - /* If there was a match, then call the handler. */ - if (mask != 0) - (*file_ptr->proc) (file_ptr->error, file_ptr->client_data); - break; - } - } -} - -/* Called by gdb_do_one_event to wait for new events on the - monitored file descriptors. Queue file events as they are - detected by the poll. - If there are no events, this function will block in the - call to poll. - Return -1 if there are no files descriptors to monitor, - otherwise return 0. */ -static int -gdb_wait_for_event (void) -{ - file_handler *file_ptr; - gdb_event *file_event_ptr; - int num_found = 0; - int i; - - /* Make sure all output is done before getting another event. */ - gdb_flush (gdb_stdout); - gdb_flush (gdb_stderr); - - if (gdb_notifier.num_fds == 0) - return -1; - - if (use_poll) - { -#ifdef HAVE_POLL - num_found = - poll (gdb_notifier.poll_fds, - (unsigned long) gdb_notifier.num_fds, - gdb_notifier.timeout_valid ? gdb_notifier.poll_timeout : -1); - - /* Don't print anything if we get out of poll because of a - signal. */ - if (num_found == -1 && errno != EINTR) - perror_with_name ("Poll"); -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - gdb_notifier.ready_masks[0] = gdb_notifier.check_masks[0]; - gdb_notifier.ready_masks[1] = gdb_notifier.check_masks[1]; - gdb_notifier.ready_masks[2] = gdb_notifier.check_masks[2]; - num_found = select (gdb_notifier.num_fds, - &gdb_notifier.ready_masks[0], - &gdb_notifier.ready_masks[1], - &gdb_notifier.ready_masks[2], - gdb_notifier.timeout_valid - ? &gdb_notifier.select_timeout : NULL); - - /* Clear the masks after an error from select. */ - if (num_found == -1) - { - FD_ZERO (&gdb_notifier.ready_masks[0]); - FD_ZERO (&gdb_notifier.ready_masks[1]); - FD_ZERO (&gdb_notifier.ready_masks[2]); - /* Dont print anything is we got a signal, let gdb handle it. */ - if (errno != EINTR) - perror_with_name ("Select"); - } - } - - /* Enqueue all detected file events. */ - - if (use_poll) - { -#ifdef HAVE_POLL - for (i = 0; (i < gdb_notifier.num_fds) && (num_found > 0); i++) - { - if ((gdb_notifier.poll_fds + i)->revents) - num_found--; - else - continue; - - for (file_ptr = gdb_notifier.first_file_handler; - file_ptr != NULL; - file_ptr = file_ptr->next_file) - { - if (file_ptr->fd == (gdb_notifier.poll_fds + i)->fd) - break; - } - - if (file_ptr) - { - /* Enqueue an event only if this is still a new event for - this fd. */ - if (file_ptr->ready_mask == 0) - { - file_event_ptr = create_file_event (file_ptr->fd); - async_queue_event (file_event_ptr, TAIL); - } - } - - file_ptr->ready_mask = (gdb_notifier.poll_fds + i)->revents; - } -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - for (file_ptr = gdb_notifier.first_file_handler; - (file_ptr != NULL) && (num_found > 0); - file_ptr = file_ptr->next_file) - { - int mask = 0; - - if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[0])) - mask |= GDB_READABLE; - if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[1])) - mask |= GDB_WRITABLE; - if (FD_ISSET (file_ptr->fd, &gdb_notifier.ready_masks[2])) - mask |= GDB_EXCEPTION; - - if (!mask) - continue; - else - num_found--; - - /* Enqueue an event only if this is still a new event for - this fd. */ - - if (file_ptr->ready_mask == 0) - { - file_event_ptr = create_file_event (file_ptr->fd); - async_queue_event (file_event_ptr, TAIL); - } - file_ptr->ready_mask = mask; - } - } - return 0; -} - - -/* Create an asynchronous handler, allocating memory for it. - Return a pointer to the newly created handler. - This pointer will be used to invoke the handler by - invoke_async_signal_handler. - PROC is the function to call with CLIENT_DATA argument - whenever the handler is invoked. */ -async_signal_handler * -create_async_signal_handler (sig_handler_func * proc, gdb_client_data client_data) -{ - async_signal_handler *async_handler_ptr; - - async_handler_ptr = - (async_signal_handler *) xmalloc (sizeof (async_signal_handler)); - async_handler_ptr->ready = 0; - async_handler_ptr->next_handler = NULL; - async_handler_ptr->proc = proc; - async_handler_ptr->client_data = client_data; - if (sighandler_list.first_handler == NULL) - sighandler_list.first_handler = async_handler_ptr; - else - sighandler_list.last_handler->next_handler = async_handler_ptr; - sighandler_list.last_handler = async_handler_ptr; - return async_handler_ptr; -} - -/* Mark the handler (ASYNC_HANDLER_PTR) as ready. This information will - be used when the handlers are invoked, after we have waited for - some event. The caller of this function is the interrupt handler - associated with a signal. */ -void -mark_async_signal_handler (async_signal_handler * async_handler_ptr) -{ - ((async_signal_handler *) async_handler_ptr)->ready = 1; - async_handler_ready = 1; -} - -/* Call all the handlers that are ready. */ -static void -invoke_async_signal_handler (void) -{ - async_signal_handler *async_handler_ptr; - - if (async_handler_ready == 0) - return; - async_handler_ready = 0; - - /* Invoke ready handlers. */ - - while (1) - { - for (async_handler_ptr = sighandler_list.first_handler; - async_handler_ptr != NULL; - async_handler_ptr = async_handler_ptr->next_handler) - { - if (async_handler_ptr->ready) - break; - } - if (async_handler_ptr == NULL) - break; - async_handler_ptr->ready = 0; - (*async_handler_ptr->proc) (async_handler_ptr->client_data); - } - - return; -} - -/* Delete an asynchronous handler (ASYNC_HANDLER_PTR). - Free the space allocated for it. */ -void -delete_async_signal_handler (async_signal_handler ** async_handler_ptr) -{ - async_signal_handler *prev_ptr; - - if (sighandler_list.first_handler == (*async_handler_ptr)) - { - sighandler_list.first_handler = (*async_handler_ptr)->next_handler; - if (sighandler_list.first_handler == NULL) - sighandler_list.last_handler = NULL; - } - else - { - prev_ptr = sighandler_list.first_handler; - while (prev_ptr->next_handler != (*async_handler_ptr) && prev_ptr) - prev_ptr = prev_ptr->next_handler; - prev_ptr->next_handler = (*async_handler_ptr)->next_handler; - if (sighandler_list.last_handler == (*async_handler_ptr)) - sighandler_list.last_handler = prev_ptr; - } - xfree ((*async_handler_ptr)); - (*async_handler_ptr) = NULL; -} - -/* Is it necessary to call invoke_async_signal_handler? */ -static int -check_async_ready (void) -{ - return async_handler_ready; -} - -/* Create a timer that will expire in MILLISECONDS from now. When the - timer is ready, PROC will be executed. At creation, the timer is - aded to the timers queue. This queue is kept sorted in order of - increasing timers. Return a handle to the timer struct. */ -int -create_timer (int milliseconds, timer_handler_func * proc, gdb_client_data client_data) -{ - struct gdb_timer *timer_ptr, *timer_index, *prev_timer; - struct timeval time_now, delta; - - /* compute seconds */ - delta.tv_sec = milliseconds / 1000; - /* compute microseconds */ - delta.tv_usec = (milliseconds % 1000) * 1000; - - gettimeofday (&time_now, NULL); - - timer_ptr = (struct gdb_timer *) xmalloc (sizeof (gdb_timer)); - timer_ptr->when.tv_sec = time_now.tv_sec + delta.tv_sec; - timer_ptr->when.tv_usec = time_now.tv_usec + delta.tv_usec; - /* carry? */ - if (timer_ptr->when.tv_usec >= 1000000) - { - timer_ptr->when.tv_sec += 1; - timer_ptr->when.tv_usec -= 1000000; - } - timer_ptr->proc = proc; - timer_ptr->client_data = client_data; - timer_list.num_timers++; - timer_ptr->timer_id = timer_list.num_timers; - - /* Now add the timer to the timer queue, making sure it is sorted in - increasing order of expiration. */ - - for (timer_index = timer_list.first_timer; - timer_index != NULL; - timer_index = timer_index->next) - { - /* If the seconds field is greater or if it is the same, but the - microsecond field is greater. */ - if ((timer_index->when.tv_sec > timer_ptr->when.tv_sec) || - ((timer_index->when.tv_sec == timer_ptr->when.tv_sec) - && (timer_index->when.tv_usec > timer_ptr->when.tv_usec))) - break; - } - - if (timer_index == timer_list.first_timer) - { - timer_ptr->next = timer_list.first_timer; - timer_list.first_timer = timer_ptr; - - } - else - { - for (prev_timer = timer_list.first_timer; - prev_timer->next != timer_index; - prev_timer = prev_timer->next) - ; - - prev_timer->next = timer_ptr; - timer_ptr->next = timer_index; - } - - gdb_notifier.timeout_valid = 0; - return timer_ptr->timer_id; -} - -/* There is a chance that the creator of the timer wants to get rid of - it before it expires. */ -void -delete_timer (int id) -{ - struct gdb_timer *timer_ptr, *prev_timer = NULL; - - /* Find the entry for the given timer. */ - - for (timer_ptr = timer_list.first_timer; timer_ptr != NULL; - timer_ptr = timer_ptr->next) - { - if (timer_ptr->timer_id == id) - break; - } - - if (timer_ptr == NULL) - return; - /* Get rid of the timer in the timer list. */ - if (timer_ptr == timer_list.first_timer) - timer_list.first_timer = timer_ptr->next; - else - { - for (prev_timer = timer_list.first_timer; - prev_timer->next != timer_ptr; - prev_timer = prev_timer->next) - ; - prev_timer->next = timer_ptr->next; - } - xfree (timer_ptr); - - gdb_notifier.timeout_valid = 0; -} - -/* When a timer event is put on the event queue, it will be handled by - this function. Just call the assiciated procedure and delete the - timer event from the event queue. Repeat this for each timer that - has expired. */ -static void -handle_timer_event (int dummy) -{ - struct timeval time_now; - struct gdb_timer *timer_ptr, *saved_timer; - - gettimeofday (&time_now, NULL); - timer_ptr = timer_list.first_timer; - - while (timer_ptr != NULL) - { - if ((timer_ptr->when.tv_sec > time_now.tv_sec) || - ((timer_ptr->when.tv_sec == time_now.tv_sec) && - (timer_ptr->when.tv_usec > time_now.tv_usec))) - break; - - /* Get rid of the timer from the beginning of the list. */ - timer_list.first_timer = timer_ptr->next; - saved_timer = timer_ptr; - timer_ptr = timer_ptr->next; - /* Call the procedure associated with that timer. */ - (*saved_timer->proc) (saved_timer->client_data); - xfree (saved_timer); - } - - gdb_notifier.timeout_valid = 0; -} - -/* Check whether any timers in the timers queue are ready. If at least - one timer is ready, stick an event onto the event queue. Even in - case more than one timer is ready, one event is enough, because the - handle_timer_event() will go through the timers list and call the - procedures associated with all that have expired. Update the - timeout for the select() or poll() as well. */ -static void -poll_timers (void) -{ - struct timeval time_now, delta; - gdb_event *event_ptr; - - if (timer_list.first_timer != NULL) - { - gettimeofday (&time_now, NULL); - delta.tv_sec = timer_list.first_timer->when.tv_sec - time_now.tv_sec; - delta.tv_usec = timer_list.first_timer->when.tv_usec - time_now.tv_usec; - /* borrow? */ - if (delta.tv_usec < 0) - { - delta.tv_sec -= 1; - delta.tv_usec += 1000000; - } - - /* Oops it expired already. Tell select / poll to return - immediately. (Cannot simply test if delta.tv_sec is negative - because time_t might be unsigned.) */ - if (timer_list.first_timer->when.tv_sec < time_now.tv_sec - || (timer_list.first_timer->when.tv_sec == time_now.tv_sec - && timer_list.first_timer->when.tv_usec < time_now.tv_usec)) - { - delta.tv_sec = 0; - delta.tv_usec = 0; - } - - if (delta.tv_sec == 0 && delta.tv_usec == 0) - { - event_ptr = (gdb_event *) xmalloc (sizeof (gdb_event)); - event_ptr->proc = handle_timer_event; - event_ptr->fd = timer_list.first_timer->timer_id; - async_queue_event (event_ptr, TAIL); - } - - /* Now we need to update the timeout for select/ poll, because we - don't want to sit there while this timer is expiring. */ - if (use_poll) - { -#ifdef HAVE_POLL - gdb_notifier.poll_timeout = delta.tv_sec * 1000; -#else - internal_error (__FILE__, __LINE__, - "use_poll without HAVE_POLL"); -#endif /* HAVE_POLL */ - } - else - { - gdb_notifier.select_timeout.tv_sec = delta.tv_sec; - gdb_notifier.select_timeout.tv_usec = delta.tv_usec; - } - gdb_notifier.timeout_valid = 1; - } - else - gdb_notifier.timeout_valid = 0; -} |