/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/* dbus-mainloop.c Main loop utility
*
- * Copyright (C) 2003, 2004 Red Hat, Inc.
+ * Copyright © 2003, 2004 Red Hat, Inc.
+ * Copyright © 2011 Nokia Corporation
*
* Licensed under the Academic Free License version 2.1
*
#include <dbus/dbus-hash.h>
#include <dbus/dbus-list.h>
-#include <dbus/dbus-sysdeps.h>
+#include <dbus/dbus-socket-set.h>
#include <dbus/dbus-watch.h>
#define MAINLOOP_SPEW 0
-#if MAINLOOP_SPEW
-#ifdef DBUS_ENABLE_VERBOSE_MODE
-static const char*
-watch_flags_to_string (int flags)
-{
- const char *watch_type;
-
- if ((flags & DBUS_WATCH_READABLE) &&
- (flags & DBUS_WATCH_WRITABLE))
- watch_type = "readwrite";
- else if (flags & DBUS_WATCH_READABLE)
- watch_type = "read";
- else if (flags & DBUS_WATCH_WRITABLE)
- watch_type = "write";
- else
- watch_type = "not read or write";
- return watch_type;
-}
-#endif /* DBUS_ENABLE_VERBOSE_MODE */
-#endif /* MAINLOOP_SPEW */
-
struct DBusLoop
{
int refcount;
/** fd => dbus_malloc'd DBusList ** of references to DBusWatch */
DBusHashTable *watches;
+ DBusSocketSet *socket_set;
DBusList *timeouts;
int callback_list_serial;
int watch_count;
int timeout_count;
int depth; /**< number of recursive runs */
DBusList *need_dispatch;
+ /** TRUE if we will skip a watch next time because it was OOM; becomes
+ * FALSE between polling, and dealing with the results of the poll */
+ unsigned oom_watch_pending : 1;
};
-static short
-watch_flags_to_poll_events (unsigned int flags)
-{
- short events = 0;
-
- if (flags & DBUS_WATCH_READABLE)
- events |= _DBUS_POLLIN;
- if (flags & DBUS_WATCH_WRITABLE)
- events |= _DBUS_POLLOUT;
-
- return events;
-}
-
-static unsigned int
-watch_flags_from_poll_revents (short revents)
-{
- unsigned int condition = 0;
-
- if (revents & _DBUS_POLLIN)
- condition |= DBUS_WATCH_READABLE;
- if (revents & _DBUS_POLLOUT)
- condition |= DBUS_WATCH_WRITABLE;
- if (revents & _DBUS_POLLHUP)
- condition |= DBUS_WATCH_HANGUP;
- if (revents & _DBUS_POLLERR)
- condition |= DBUS_WATCH_ERROR;
-
- return condition;
-}
-
typedef struct
{
- int refcount;
DBusTimeout *timeout;
unsigned long last_tv_sec;
unsigned long last_tv_usec;
return NULL;
cb->timeout = timeout;
- _dbus_get_current_time (&cb->last_tv_sec,
- &cb->last_tv_usec);
- cb->refcount = 1;
- return cb;
-}
-
-static TimeoutCallback *
-timeout_callback_ref (TimeoutCallback *cb)
-{
- _dbus_assert (cb->refcount > 0);
-
- cb->refcount += 1;
-
+ _dbus_get_monotonic_time (&cb->last_tv_sec,
+ &cb->last_tv_usec);
return cb;
}
static void
-timeout_callback_unref (TimeoutCallback *cb)
+timeout_callback_free (TimeoutCallback *cb)
{
- _dbus_assert (cb->refcount > 0);
-
- cb->refcount -= 1;
-
- if (cb->refcount == 0)
- {
- dbus_free (cb);
- }
+ dbus_free (cb);
}
static void
loop->watches = _dbus_hash_table_new (DBUS_HASH_INT, NULL,
free_watch_table_entry);
- if (loop->watches == NULL)
+ loop->socket_set = _dbus_socket_set_new (0);
+
+ if (loop->watches == NULL || loop->socket_set == NULL)
{
+ if (loop->watches != NULL)
+ _dbus_hash_table_unref (loop->watches);
+
+ if (loop->socket_set != NULL)
+ _dbus_socket_set_free (loop->socket_set);
+
dbus_free (loop);
return NULL;
}
}
_dbus_hash_table_unref (loop->watches);
+ _dbus_socket_set_free (loop->socket_set);
dbus_free (loop);
}
}
int fd)
{
DBusList *link;
- DBusList *next;
DBusList **watches;
_dbus_warn ("invalid request, socket fd %d not open\n", fd);
_dbus_hash_table_remove_int (loop->watches, fd);
}
-static void
+static dbus_bool_t
gc_watch_table_entry (DBusLoop *loop,
DBusList **watches,
int fd)
{
/* If watches is already NULL we have nothing to do */
if (watches == NULL)
- return;
+ return FALSE;
/* We can't GC hash table entries if they're non-empty lists */
if (*watches != NULL)
- return;
+ return FALSE;
_dbus_hash_table_remove_int (loop->watches, fd);
+ return TRUE;
+}
+
+static void
+refresh_watches_for_fd (DBusLoop *loop,
+ DBusList **watches,
+ int fd)
+{
+ DBusList *link;
+ unsigned int flags = 0;
+ dbus_bool_t interested = FALSE;
+
+ _dbus_assert (fd != -1);
+
+ if (watches == NULL)
+ watches = _dbus_hash_table_lookup_int (loop->watches, fd);
+
+ /* we allocated this in the first _dbus_loop_add_watch for the fd, and keep
+ * it until there are none left */
+ _dbus_assert (watches != NULL);
+
+ for (link = _dbus_list_get_first_link (watches);
+ link != NULL;
+ link = _dbus_list_get_next_link (watches, link))
+ {
+ if (dbus_watch_get_enabled (link->data) &&
+ !_dbus_watch_get_oom_last_time (link->data))
+ {
+ flags |= dbus_watch_get_flags (link->data);
+ interested = TRUE;
+ }
+ }
+
+ if (interested)
+ _dbus_socket_set_enable (loop->socket_set, fd, flags);
+ else
+ _dbus_socket_set_disable (loop->socket_set, fd);
}
dbus_bool_t
if (watches == NULL)
return FALSE;
- if (_dbus_list_append (watches, _dbus_watch_ref (watch)))
- {
- loop->callback_list_serial += 1;
- loop->watch_count += 1;
- }
- else
+ if (!_dbus_list_append (watches, _dbus_watch_ref (watch)))
{
_dbus_watch_unref (watch);
gc_watch_table_entry (loop, watches, fd);
- return FALSE;
- }
+ return FALSE;
+ }
+
+ if (_dbus_list_length_is_one (watches))
+ {
+ if (!_dbus_socket_set_add (loop->socket_set, fd,
+ dbus_watch_get_flags (watch),
+ dbus_watch_get_enabled (watch)))
+ {
+ _dbus_hash_table_remove_int (loop->watches, fd);
+ return FALSE;
+ }
+ }
+ else
+ {
+ /* we're modifying, not adding, which can't fail with OOM */
+ refresh_watches_for_fd (loop, watches, fd);
+ }
+ loop->callback_list_serial += 1;
+ loop->watch_count += 1;
return TRUE;
}
void
+_dbus_loop_toggle_watch (DBusLoop *loop,
+ DBusWatch *watch)
+{
+ refresh_watches_for_fd (loop, NULL, dbus_watch_get_socket (watch));
+}
+
+void
_dbus_loop_remove_watch (DBusLoop *loop,
DBusWatch *watch)
{
_dbus_watch_unref (this);
/* if that was the last watch for that fd, drop the hash table
- * entry too */
- gc_watch_table_entry (loop, watches, fd);
+ * entry, and stop reserving space for it in the socket set */
+ if (gc_watch_table_entry (loop, watches, fd))
+ {
+ _dbus_socket_set_remove (loop->socket_set, fd);
+ }
return;
}
}
else
{
- timeout_callback_unref (tcb);
+ timeout_callback_free (tcb);
return FALSE;
}
_dbus_list_remove_link (&loop->timeouts, link);
loop->callback_list_serial += 1;
loop->timeout_count -= 1;
- timeout_callback_unref (this);
+ timeout_callback_free (this);
return;
}
{
#define N_STACK_DESCRIPTORS 64
dbus_bool_t retval;
- DBusPollFD *fds;
- DBusPollFD stack_fds[N_STACK_DESCRIPTORS];
- int n_fds;
+ DBusSocketEvent ready_fds[N_STACK_DESCRIPTORS];
int i;
DBusList *link;
int n_ready;
int initial_serial;
long timeout;
- dbus_bool_t oom_watch_pending;
int orig_depth;
- DBusHashIter hash_iter;
retval = FALSE;
- fds = NULL;
- n_fds = 0;
- oom_watch_pending = FALSE;
orig_depth = loop->depth;
#if MAINLOOP_SPEW
loop->timeouts == NULL)
goto next_iteration;
- if (loop->watch_count > N_STACK_DESCRIPTORS)
- {
- fds = dbus_new0 (DBusPollFD, loop->watch_count);
-
- while (fds == NULL)
- {
- _dbus_wait_for_memory ();
- fds = dbus_new0 (DBusPollFD, loop->watch_count);
- }
- }
- else
- {
- fds = stack_fds;
- }
-
- /* fill our array of fds and watches */
- n_fds = 0;
- _dbus_hash_iter_init (loop->watches, &hash_iter);
-
- while (_dbus_hash_iter_next (&hash_iter))
- {
- DBusList **watches;
- unsigned int flags;
- int fd;
-
- fd = _dbus_hash_iter_get_int_key (&hash_iter);
- watches = _dbus_hash_iter_get_value (&hash_iter);
- flags = 0;
-
- for (link = _dbus_list_get_first_link (watches);
- link != NULL;
- link = _dbus_list_get_next_link (watches, link))
- {
- DBusWatch *watch = link->data;
-
- if (_dbus_watch_get_oom_last_time (watch))
- {
- /* we skip this one this time, but reenable it next time,
- * and have a timeout on this iteration
- */
- _dbus_watch_set_oom_last_time (watch, FALSE);
- oom_watch_pending = TRUE;
-
- retval = TRUE; /* return TRUE here to keep the loop going,
- * since we don't know the watch is inactive
- */
-
-#if MAINLOOP_SPEW
- _dbus_verbose (" skipping watch on fd %d as it was out of memory last time\n",
- fd);
-#endif
- }
- else if (dbus_watch_get_enabled (watch))
- {
- flags |= dbus_watch_get_flags (watch);
- }
- }
-
- if (flags != 0)
- {
- fds[n_fds].fd = fd;
- fds[n_fds].revents = 0;
- fds[n_fds].events = watch_flags_to_poll_events (flags);
-
-#if MAINLOOP_SPEW
- _dbus_verbose (" polling watch on fd %d %s\n",
- loop->fds[loop->n_fds].fd, watch_flags_to_string (flags));
-#endif
-
- n_fds += 1;
- }
- else
- {
-#if MAINLOOP_SPEW
- _dbus_verbose (" skipping disabled watch on fd %d %s\n",
- fd,
- watch_flags_to_string (dbus_watch_get_flags (watch)));
-#endif
- }
- }
-
timeout = -1;
if (loop->timeout_count > 0)
{
unsigned long tv_sec;
unsigned long tv_usec;
- _dbus_get_current_time (&tv_sec, &tv_usec);
+ _dbus_get_monotonic_time (&tv_sec, &tv_usec);
link = _dbus_list_get_first_link (&loop->timeouts);
while (link != NULL)
#endif
}
- /* if a watch is OOM, don't wait longer than the OOM
+ /* if a watch was OOM last time, don't wait longer than the OOM
* wait to re-enable it
*/
- if (oom_watch_pending)
+ if (loop->oom_watch_pending)
timeout = MIN (timeout, _dbus_get_oom_wait ());
#if MAINLOOP_SPEW
_dbus_verbose (" polling on %d descriptors timeout %ld\n", n_fds, timeout);
#endif
-
- n_ready = _dbus_poll (fds, n_fds, timeout);
+
+ n_ready = _dbus_socket_set_poll (loop->socket_set, ready_fds,
+ _DBUS_N_ELEMENTS (ready_fds), timeout);
+
+ /* re-enable any watches we skipped this time */
+ if (loop->oom_watch_pending)
+ {
+ DBusHashIter hash_iter;
+
+ loop->oom_watch_pending = FALSE;
+
+ _dbus_hash_iter_init (loop->watches, &hash_iter);
+
+ while (_dbus_hash_iter_next (&hash_iter))
+ {
+ DBusList **watches;
+ int fd;
+ dbus_bool_t changed;
+
+ changed = FALSE;
+ fd = _dbus_hash_iter_get_int_key (&hash_iter);
+ watches = _dbus_hash_iter_get_value (&hash_iter);
+
+ for (link = _dbus_list_get_first_link (watches);
+ link != NULL;
+ link = _dbus_list_get_next_link (watches, link))
+ {
+ DBusWatch *watch = link->data;
+
+ if (_dbus_watch_get_oom_last_time (watch))
+ {
+ _dbus_watch_set_oom_last_time (watch, FALSE);
+ changed = TRUE;
+ }
+ }
+
+ if (changed)
+ refresh_watches_for_fd (loop, watches, fd);
+ }
+
+ retval = TRUE; /* return TRUE here to keep the loop going,
+ * since we don't know the watch was inactive */
+ }
initial_serial = loop->callback_list_serial;
unsigned long tv_sec;
unsigned long tv_usec;
- _dbus_get_current_time (&tv_sec, &tv_usec);
+ _dbus_get_monotonic_time (&tv_sec, &tv_usec);
/* It'd be nice to avoid this O(n) thingy here */
link = _dbus_list_get_first_link (&loop->timeouts);
link = next;
}
}
-
+
if (n_ready > 0)
{
- for (i = 0; i < n_fds; i++)
+ for (i = 0; i < n_ready; i++)
{
DBusList **watches;
DBusList *next;
unsigned int condition;
+ dbus_bool_t any_oom;
/* FIXME I think this "restart if we change the watches"
* approach could result in starving watches
if (loop->depth != orig_depth)
goto next_iteration;
- if (fds[i].revents == 0)
- continue;
+ _dbus_assert (ready_fds[i].flags != 0);
- if (_DBUS_UNLIKELY (fds[i].revents & _DBUS_POLLNVAL))
+ if (_DBUS_UNLIKELY (ready_fds[i].flags & _DBUS_WATCH_NVAL))
{
- cull_watches_for_invalid_fd (loop, fds[i].fd);
+ cull_watches_for_invalid_fd (loop, ready_fds[i].fd);
goto next_iteration;
}
- condition = watch_flags_from_poll_revents (fds[i].revents);
+ condition = ready_fds[i].flags;
+ _dbus_assert ((condition & _DBUS_WATCH_NVAL) == 0);
/* condition may still be 0 if we got some
* weird POLLFOO thing like POLLWRBAND
if (condition == 0)
continue;
- watches = _dbus_hash_table_lookup_int (loop->watches, fds[i].fd);
+ watches = _dbus_hash_table_lookup_int (loop->watches,
+ ready_fds[i].fd);
if (watches == NULL)
continue;
+ any_oom = FALSE;
+
for (link = _dbus_list_get_first_link (watches);
link != NULL;
link = next)
if (oom)
{
_dbus_watch_set_oom_last_time (watch, TRUE);
+ loop->oom_watch_pending = TRUE;
+ any_oom = TRUE;
}
#if MAINLOOP_SPEW
/* We re-check this every time, in case the callback
* added/removed watches, which might make our position in
* the linked list invalid. See the FIXME above. */
- if (initial_serial != loop->callback_list_serial)
- goto next_iteration;
+ if (initial_serial != loop->callback_list_serial ||
+ loop->depth != orig_depth)
+ {
+ if (any_oom)
+ refresh_watches_for_fd (loop, NULL, ready_fds[i].fd);
- if (loop->depth != orig_depth)
- goto next_iteration;
+ goto next_iteration;
+ }
}
}
+
+ if (any_oom)
+ refresh_watches_for_fd (loop, watches, ready_fds[i].fd);
}
}
#if MAINLOOP_SPEW
_dbus_verbose (" moving to next iteration\n");
#endif
-
- if (fds && fds != stack_fds)
- dbus_free (fds);
if (_dbus_loop_dispatch (loop))
retval = TRUE;
int
_dbus_get_oom_wait (void)
{
-#ifdef DBUS_BUILD_TESTS
+#ifdef DBUS_ENABLE_EMBEDDED_TESTS
/* make tests go fast */
return 0;
#else
projects / platform / upstream / dbus.git / blobdiff