diff options
Diffstat (limited to 'bus/loop.c')
| -rw-r--r-- | bus/loop.c | 698 |
1 files changed, 0 insertions, 698 deletions
diff --git a/bus/loop.c b/bus/loop.c deleted file mode 100644 index e2e129eb..00000000 --- a/bus/loop.c +++ /dev/null @@ -1,698 +0,0 @@ -/* -*- mode: C; c-file-style: "gnu" -*- */ -/* loop.c Main loop for daemon - * - * Copyright (C) 2003 Red Hat, Inc. - * - * Licensed under the Academic Free License version 1.2 - * - * 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 "loop.h" -#include "utils.h" -#include <dbus/dbus-list.h> -#include <dbus/dbus-sysdeps.h> - -struct BusLoop -{ - int refcount; - DBusList *callbacks; - int callback_list_serial; - int watch_count; - int timeout_count; - int depth; /**< number of recursive runs */ -}; - -typedef enum -{ - CALLBACK_WATCH, - CALLBACK_TIMEOUT -} CallbackType; - -typedef struct -{ - CallbackType type; - void *data; - DBusFreeFunction free_data_func; -} Callback; - -typedef struct -{ - Callback callback; - BusWatchFunction function; - DBusWatch *watch; - /* last watch handle failed due to OOM */ - unsigned int last_iteration_oom : 1; -} WatchCallback; - -typedef struct -{ - Callback callback; - DBusTimeout *timeout; - BusTimeoutFunction function; - unsigned long last_tv_sec; - unsigned long last_tv_usec; -} TimeoutCallback; - -#define WATCH_CALLBACK(callback) ((WatchCallback*)callback) -#define TIMEOUT_CALLBACK(callback) ((TimeoutCallback*)callback) - -static WatchCallback* -watch_callback_new (DBusWatch *watch, - BusWatchFunction function, - void *data, - DBusFreeFunction free_data_func) -{ - WatchCallback *cb; - - cb = dbus_new (WatchCallback, 1); - if (cb == NULL) - return NULL; - - cb->watch = watch; - cb->function = function; - cb->last_iteration_oom = FALSE; - cb->callback.type = CALLBACK_WATCH; - cb->callback.data = data; - cb->callback.free_data_func = free_data_func; - - return cb; -} - -static TimeoutCallback* -timeout_callback_new (DBusTimeout *timeout, - BusTimeoutFunction function, - void *data, - DBusFreeFunction free_data_func) -{ - TimeoutCallback *cb; - - cb = dbus_new (TimeoutCallback, 1); - if (cb == NULL) - return NULL; - - cb->timeout = timeout; - cb->function = function; - _dbus_get_current_time (&cb->last_tv_sec, - &cb->last_tv_usec); - cb->callback.type = CALLBACK_TIMEOUT; - cb->callback.data = data; - cb->callback.free_data_func = free_data_func; - - return cb; -} - -static void -callback_free (Callback *cb) -{ - if (cb->free_data_func) - (* cb->free_data_func) (cb->data); - - dbus_free (cb); -} - -static dbus_bool_t -add_callback (BusLoop *loop, - Callback *cb) -{ - if (!_dbus_list_append (&loop->callbacks, cb)) - return FALSE; - - loop->callback_list_serial += 1; - - switch (cb->type) - { - case CALLBACK_WATCH: - loop->watch_count += 1; - break; - case CALLBACK_TIMEOUT: - loop->timeout_count += 1; - break; - } - - return TRUE; -} - -static void -remove_callback (BusLoop *loop, - DBusList *link) -{ - Callback *cb = link->data; - - switch (cb->type) - { - case CALLBACK_WATCH: - loop->watch_count -= 1; - break; - case CALLBACK_TIMEOUT: - loop->timeout_count -= 1; - break; - } - - callback_free (cb); - _dbus_list_remove_link (&loop->callbacks, link); - loop->callback_list_serial += 1; -} - -BusLoop* -bus_loop_new (void) -{ - BusLoop *loop; - - loop = dbus_new0 (BusLoop, 1); - if (loop == NULL) - return NULL; - - loop->refcount = 1; - - return loop; -} - -void -bus_loop_ref (BusLoop *loop) -{ - _dbus_assert (loop != NULL); - _dbus_assert (loop->refcount > 0); - - loop->refcount += 1; -} - -void -bus_loop_unref (BusLoop *loop) -{ - _dbus_assert (loop != NULL); - _dbus_assert (loop->refcount > 0); - - loop->refcount -= 1; - if (loop->refcount == 0) - { - - dbus_free (loop); - } -} - -dbus_bool_t -bus_loop_add_watch (BusLoop *loop, - DBusWatch *watch, - BusWatchFunction function, - void *data, - DBusFreeFunction free_data_func) -{ - WatchCallback *wcb; - - wcb = watch_callback_new (watch, function, data, free_data_func); - if (wcb == NULL) - return FALSE; - - if (!add_callback (loop, (Callback*) wcb)) - { - wcb->callback.free_data_func = NULL; /* don't want to have this side effect */ - callback_free ((Callback*) wcb); - return FALSE; - } - - return TRUE; -} - -void -bus_loop_remove_watch (BusLoop *loop, - DBusWatch *watch, - BusWatchFunction function, - void *data) -{ - DBusList *link; - - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *this = link->data; - - if (this->type == CALLBACK_WATCH && - WATCH_CALLBACK (this)->watch == watch && - this->data == data && - WATCH_CALLBACK (this)->function == function) - { - remove_callback (loop, link); - - return; - } - - link = next; - } - - _dbus_warn ("could not find watch %p function %p data %p to remove\n", - watch, function, data); -} - -dbus_bool_t -bus_loop_add_timeout (BusLoop *loop, - DBusTimeout *timeout, - BusTimeoutFunction function, - void *data, - DBusFreeFunction free_data_func) -{ - TimeoutCallback *tcb; - - tcb = timeout_callback_new (timeout, function, data, free_data_func); - if (tcb == NULL) - return FALSE; - - if (!add_callback (loop, (Callback*) tcb)) - { - tcb->callback.free_data_func = NULL; /* don't want to have this side effect */ - callback_free ((Callback*) tcb); - return FALSE; - } - - return TRUE; -} - -void -bus_loop_remove_timeout (BusLoop *loop, - DBusTimeout *timeout, - BusTimeoutFunction function, - void *data) -{ - DBusList *link; - - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *this = link->data; - - if (this->type == CALLBACK_TIMEOUT && - TIMEOUT_CALLBACK (this)->timeout == timeout && - this->data == data && - TIMEOUT_CALLBACK (this)->function == function) - { - remove_callback (loop, link); - - return; - } - - link = next; - } - - _dbus_warn ("could not find timeout %p function %p data %p to remove\n", - timeout, function, data); -} - -/* Convolutions from GLib, there really must be a better way - * to do this. - */ -static dbus_bool_t -check_timeout (unsigned long tv_sec, - unsigned long tv_usec, - TimeoutCallback *tcb, - int *timeout) -{ - long sec; - long msec; - unsigned long expiration_tv_sec; - unsigned long expiration_tv_usec; - long interval_seconds; - long interval_milliseconds; - int interval; - - interval = dbus_timeout_get_interval (tcb->timeout); - - interval_seconds = interval / 1000; - interval_milliseconds = interval - interval_seconds * 1000; - - expiration_tv_sec = tcb->last_tv_sec + interval_seconds; - expiration_tv_usec = tcb->last_tv_usec + interval_milliseconds * 1000; - if (expiration_tv_usec >= 1000000) - { - expiration_tv_usec -= 1000000; - expiration_tv_sec += 1; - } - - sec = expiration_tv_sec - tv_sec; - msec = (expiration_tv_usec - tv_usec) / 1000; - -#if 0 - printf ("Interval is %ld seconds %ld msecs\n", - interval_seconds, - interval_milliseconds); - printf ("Now is %lu seconds %lu usecs\n", - tv_sec, tv_usec); - printf ("Exp is %lu seconds %lu usecs\n", - expiration_tv_sec, expiration_tv_usec); - printf ("Pre-correction, remaining sec %ld msec %ld\n", sec, msec); -#endif - - /* We do the following in a rather convoluted fashion to deal with - * the fact that we don't have an integral type big enough to hold - * the difference of two timevals in millseconds. - */ - if (sec < 0 || (sec == 0 && msec < 0)) - msec = 0; - else - { - if (msec < 0) - { - msec += 1000; - sec -= 1; - } - - if (sec > interval_seconds || - (sec == interval_seconds && msec > interval_milliseconds)) - { - /* The system time has been set backwards, reset the timeout */ - tcb->last_tv_sec = tv_sec; - tcb->last_tv_usec = tv_usec; - - msec = MIN (_DBUS_INT_MAX, interval); - - _dbus_verbose ("System clock went backward\n"); - } - else - { - msec = MIN (_DBUS_INT_MAX, (unsigned int)msec + 1000 * (unsigned int)sec); - } - } - - *timeout = msec; - -#if 0 - printf ("Timeout expires in %d milliseconds\n", *timeout); -#endif - - return msec == 0; -} - -/* Returns TRUE if we have any timeouts or ready file descriptors, - * which is just used in test code as a debug hack - */ - -dbus_bool_t -bus_loop_iterate (BusLoop *loop, - dbus_bool_t block) -{ - dbus_bool_t retval; - DBusPollFD *fds; - int n_fds; - WatchCallback **watches_for_fds; - int i; - DBusList *link; - int n_ready; - int initial_serial; - long timeout; - dbus_bool_t oom_watch_pending; - int orig_depth; - - retval = FALSE; - - fds = NULL; - watches_for_fds = NULL; - oom_watch_pending = FALSE; - orig_depth = loop->depth; - -#if 0 - _dbus_verbose (" iterate %d timeouts %d watches\n", - loop->timeout_count, loop->watch_count); -#endif - - if (loop->callbacks == NULL) - { - bus_loop_quit (loop); - goto next_iteration; - } - - /* count enabled watches */ - n_fds = 0; - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *cb = link->data; - if (cb->type == CALLBACK_WATCH) - { - WatchCallback *wcb = WATCH_CALLBACK (cb); - - if (!wcb->last_iteration_oom && - dbus_watch_get_enabled (wcb->watch)) - ++n_fds; - } - - link = next; - } - - /* fill our array of fds and watches */ - if (n_fds > 0) - { - fds = dbus_new0 (DBusPollFD, n_fds); - while (fds == NULL) - { - bus_wait_for_memory (); - fds = dbus_new0 (DBusPollFD, n_fds); - } - - watches_for_fds = dbus_new (WatchCallback*, n_fds); - while (watches_for_fds == NULL) - { - bus_wait_for_memory (); - watches_for_fds = dbus_new (WatchCallback*, n_fds); - } - - i = 0; - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *cb = link->data; - if (cb->type == CALLBACK_WATCH) - { - unsigned int flags; - WatchCallback *wcb = WATCH_CALLBACK (cb); - - if (wcb->last_iteration_oom) - { - /* we skip this one this time, but reenable it next time, - * and have a timeout on this iteration - */ - wcb->last_iteration_oom = FALSE; - oom_watch_pending = TRUE; - } - else if (dbus_watch_get_enabled (wcb->watch)) - { - watches_for_fds[i] = wcb; - - flags = dbus_watch_get_flags (wcb->watch); - - fds[i].fd = dbus_watch_get_fd (wcb->watch); - if (flags & DBUS_WATCH_READABLE) - fds[i].events |= _DBUS_POLLIN; - if (flags & DBUS_WATCH_WRITABLE) - fds[i].events |= _DBUS_POLLOUT; - - ++i; - } - } - - link = next; - } - - _dbus_assert (i == n_fds); - } - - timeout = -1; - if (loop->timeout_count > 0) - { - unsigned long tv_sec; - unsigned long tv_usec; - - retval = TRUE; - - _dbus_get_current_time (&tv_sec, &tv_usec); - - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *cb = link->data; - - if (cb->type == CALLBACK_TIMEOUT && - dbus_timeout_get_enabled (TIMEOUT_CALLBACK (cb)->timeout)) - { - TimeoutCallback *tcb = TIMEOUT_CALLBACK (cb); - int msecs_remaining; - - check_timeout (tv_sec, tv_usec, tcb, &msecs_remaining); - - if (timeout < 0) - timeout = msecs_remaining; - else - timeout = MIN (msecs_remaining, timeout); - - _dbus_assert (timeout >= 0); - - if (timeout == 0) - break; /* it's not going to get shorter... */ - } - - link = next; - } - } - - if (!block) - { - timeout = 0; -#if 0 - printf ("timeout is 0 as we aren't blocking\n"); -#endif - } - - /* if a watch is OOM, don't wait longer than the OOM - * wait to re-enable it - */ - if (oom_watch_pending) - timeout = MIN (timeout, bus_get_oom_wait ()); - - n_ready = _dbus_poll (fds, n_fds, timeout); - - initial_serial = loop->callback_list_serial; - - if (loop->timeout_count > 0) - { - unsigned long tv_sec; - unsigned long tv_usec; - - _dbus_get_current_time (&tv_sec, &tv_usec); - - /* It'd be nice to avoid this O(n) thingy here */ - link = _dbus_list_get_first_link (&loop->callbacks); - while (link != NULL) - { - DBusList *next = _dbus_list_get_next_link (&loop->callbacks, link); - Callback *cb = link->data; - - if (initial_serial != loop->callback_list_serial) - goto next_iteration; - - if (loop->depth != orig_depth) - goto next_iteration; - - if (cb->type == CALLBACK_TIMEOUT && - dbus_timeout_get_enabled (TIMEOUT_CALLBACK (cb)->timeout)) - { - TimeoutCallback *tcb = TIMEOUT_CALLBACK (cb); - int msecs_remaining; - - if (check_timeout (tv_sec, tv_usec, - tcb, &msecs_remaining)) - { - /* Save last callback time and fire this timeout */ - tcb->last_tv_sec = tv_sec; - tcb->last_tv_usec = tv_usec; - -#if 0 - printf (" invoking timeout\n"); -#endif - - (* tcb->function) (tcb->timeout, - cb->data); - } - } - - link = next; - } - } - - if (n_ready > 0) - { - i = 0; - while (i < n_fds) - { - /* FIXME I think this "restart if we change the watches" - * approach could result in starving watches - * toward the end of the list. - */ - if (initial_serial != loop->callback_list_serial) - goto next_iteration; - - if (loop->depth != orig_depth) - goto next_iteration; - - if (fds[i].revents != 0) - { - WatchCallback *wcb; - unsigned int condition; - - wcb = watches_for_fds[i]; - - condition = 0; - if (fds[i].revents & _DBUS_POLLIN) - condition |= DBUS_WATCH_READABLE; - if (fds[i].revents & _DBUS_POLLOUT) - condition |= DBUS_WATCH_WRITABLE; - if (fds[i].revents & _DBUS_POLLHUP) - condition |= DBUS_WATCH_HANGUP; - if (fds[i].revents & _DBUS_POLLERR) - condition |= DBUS_WATCH_ERROR; - - /* condition may still be 0 if we got some - * weird POLLFOO thing like POLLWRBAND - */ - - if (condition != 0 && - dbus_watch_get_enabled (wcb->watch)) - { - if (!(* wcb->function) (wcb->watch, - condition, - ((Callback*)wcb)->data)) - wcb->last_iteration_oom = TRUE; - - retval = TRUE; - } - } - - ++i; - } - } - - next_iteration: - dbus_free (fds); - dbus_free (watches_for_fds); - - return retval; -} - -void -bus_loop_run (BusLoop *loop) -{ - int our_exit_depth; - - bus_loop_ref (loop); - - our_exit_depth = loop->depth; - loop->depth += 1; - - while (loop->depth != our_exit_depth) - bus_loop_iterate (loop, TRUE); - - bus_loop_unref (loop); -} - -void -bus_loop_quit (BusLoop *loop) -{ - _dbus_assert (loop->depth > 0); - - loop->depth -= 1; -} |