* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif /* HAVE_SYS_TIME_H */
-#ifdef HAVE_UNISTD_H
+#ifdef G_OS_UNIX
#include <unistd.h>
-#endif /* HAVE_UNISTD_H */
+#endif /* G_OS_UNIX */
#include <errno.h>
#include <string.h>
#include <windows.h>
#endif /* G_OS_WIN32 */
-#ifdef G_OS_BEOS
-#include <sys/socket.h>
-#include <sys/wait.h>
-#endif /* G_OS_BEOS */
+#ifdef HAVE_MACH_MACH_TIME_H
+#include <mach/mach_time.h>
+#endif
+
+#include "glib_trace.h"
#include "gmain.h"
#endif
#include "gwakeup.h"
-
+#include "gmain-internal.h"
+#include "glib-init.h"
#include "glib-private.h"
/**
* GTK+ contains wrappers of some of these functions, e.g. gtk_main(),
* gtk_main_quit() and gtk_events_pending().
*
- * <refsect2><title>Creating new source types</title>
- * <para>One of the unusual features of the #GMainLoop functionality
+ * ## Creating new source types
+ *
+ * One of the unusual features of the #GMainLoop functionality
* is that new types of event source can be created and used in
* addition to the builtin type of event source. A new event source
* type is used for handling GDK events. A new source type is created
- * by <firstterm>deriving</firstterm> from the #GSource structure.
- * The derived type of source is represented by a structure that has
- * the #GSource structure as a first element, and other elements specific
- * to the new source type. To create an instance of the new source type,
- * call g_source_new() passing in the size of the derived structure and
+ * by "deriving" from the #GSource structure. The derived type of
+ * source is represented by a structure that has the #GSource structure
+ * as a first element, and other elements specific to the new source
+ * type. To create an instance of the new source type, call
+ * g_source_new() passing in the size of the derived structure and
* a table of functions. These #GSourceFuncs determine the behavior of
- * the new source type.</para>
- * <para>New source types basically interact with the main context
+ * the new source type.
+ *
+ * New source types basically interact with the main context
* in two ways. Their prepare function in #GSourceFuncs can set a timeout
* to determine the maximum amount of time that the main loop will sleep
* before checking the source again. In addition, or as well, the source
* can add file descriptors to the set that the main context checks using
- * g_source_add_poll().</para>
- * </refsect2>
- * <refsect2><title>Customizing the main loop iteration</title>
- * <para>Single iterations of a #GMainContext can be run with
+ * g_source_add_poll().
+ *
+ * ## Customizing the main loop iteration
+ *
+ * Single iterations of a #GMainContext can be run with
* g_main_context_iteration(). In some cases, more detailed control
* of exactly how the details of the main loop work is desired, for
* instance, when integrating the #GMainLoop with an external main loop.
* In such cases, you can call the component functions of
* g_main_context_iteration() directly. These functions are
* g_main_context_prepare(), g_main_context_query(),
- * g_main_context_check() and g_main_context_dispatch().</para>
- * <para>The operation of these functions can best be seen in terms
- * of a state diagram, as shown in <xref linkend="mainloop-states"/>.</para>
- * <figure id="mainloop-states"><title>States of a Main Context</title>
- * <graphic fileref="mainloop-states.gif" format="GIF"></graphic>
- * </figure>
- * </refsect2>
- *
- * On Unix, the GLib mainloop is incompatible with fork(). Any program
+ * g_main_context_check() and g_main_context_dispatch().
+ *
+ * ## State of a Main Context # {#mainloop-states}
+ *
+ * The operation of these functions can best be seen in terms
+ * of a state diagram, as shown in this image.
+ *
+ * ![](mainloop-states.gif)
+ *
+ * On UNIX, the GLib mainloop is incompatible with fork(). Any program
* using the mainloop must either exec() or exit() from the child
* without returning to the mainloop.
*/
typedef enum
{
G_SOURCE_READY = 1 << G_HOOK_FLAG_USER_SHIFT,
- G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1)
+ G_SOURCE_CAN_RECURSE = 1 << (G_HOOK_FLAG_USER_SHIFT + 1),
+ G_SOURCE_BLOCKED = 1 << (G_HOOK_FLAG_USER_SHIFT + 2)
} GSourceFlags;
+typedef struct _GSourceList GSourceList;
+
+struct _GSourceList
+{
+ GSource *head, *tail;
+ gint priority;
+};
+
typedef struct _GMainWaiter GMainWaiter;
struct _GMainWaiter
struct _GMainDispatch
{
gint depth;
- GSList *dispatching_sources; /* stack of current sources */
+ GSource *source;
};
#ifdef G_MAIN_POLL_DEBUG
gint ref_count;
+ GHashTable *sources; /* guint -> GSource */
+
GPtrArray *pending_dispatches;
gint timeout; /* Timeout for current iteration */
guint next_id;
- GSource *source_list;
+ GList *source_lists;
gint in_check_or_prepare;
GPollRec *poll_records, *poll_records_tail;
struct _GTimeoutSource
{
GSource source;
- gint64 expiration;
guint interval;
gboolean seconds;
};
{
GSList *child_sources;
GSource *parent_source;
+
+ gint64 ready_time;
+
+ /* This is currently only used on UNIX, but we always declare it (and
+ * let it remain empty on Windows) to avoid #ifdef all over the place.
+ */
+ GSList *fds;
};
+typedef struct _GSourceIter
+{
+ GMainContext *context;
+ gboolean may_modify;
+ GList *current_list;
+ GSource *source;
+} GSourceIter;
+
#define LOCK_CONTEXT(context) g_mutex_lock (&context->mutex)
#define UNLOCK_CONTEXT(context) g_mutex_unlock (&context->mutex)
#define G_THREAD_SELF g_thread_self ()
#define SOURCE_DESTROYED(source) (((source)->flags & G_HOOK_FLAG_ACTIVE) == 0)
-#define SOURCE_BLOCKED(source) (((source)->flags & G_HOOK_FLAG_IN_CALL) != 0 && \
- ((source)->flags & G_SOURCE_CAN_RECURSE) == 0)
+#define SOURCE_BLOCKED(source) (((source)->flags & G_SOURCE_BLOCKED) != 0)
#define SOURCE_UNREF(source, context) \
G_STMT_START { \
static void g_source_set_priority_unlocked (GSource *source,
GMainContext *context,
gint priority);
+static void g_child_source_remove_internal (GSource *child_source,
+ GMainContext *context);
+
static void g_main_context_poll (GMainContext *context,
gint timeout,
gint priority,
static void g_main_context_remove_poll_unlocked (GMainContext *context,
GPollFD *fd);
-static gboolean g_timeout_prepare (GSource *source,
- gint *timeout);
-static gboolean g_timeout_check (GSource *source);
+static void g_source_iter_init (GSourceIter *iter,
+ GMainContext *context,
+ gboolean may_modify);
+static gboolean g_source_iter_next (GSourceIter *iter,
+ GSource **source);
+static void g_source_iter_clear (GSourceIter *iter);
+
static gboolean g_timeout_dispatch (GSource *source,
GSourceFunc callback,
gpointer user_data);
GSourceFunc callback,
gpointer user_data);
+static void block_source (GSource *source);
+
static GMainContext *glib_worker_context;
-static gboolean g_main_context_fork_detected;
G_LOCK_DEFINE_STATIC (main_loop);
static GMainContext *default_main_context;
/* UNIX signals work by marking one of these variables then waking the
* worker context to check on them and dispatch accordingly.
*/
-static volatile gchar unix_signal_pending[NSIG];
-static volatile gboolean any_unix_signal_pending;
+#ifdef HAVE_SIG_ATOMIC_T
+static volatile sig_atomic_t unix_signal_pending[NSIG];
+static volatile sig_atomic_t any_unix_signal_pending;
+#else
+static volatile int unix_signal_pending[NSIG];
+static volatile int any_unix_signal_pending;
+#endif
+static volatile guint unix_signal_refcount[NSIG];
/* Guards all the data below */
G_LOCK_DEFINE_STATIC (unix_signal_lock);
static GSList *unix_signal_watches;
static GSList *unix_child_watches;
-static GSourceFuncs g_unix_signal_funcs =
+GSourceFuncs g_unix_signal_funcs =
{
g_unix_signal_watch_prepare,
g_unix_signal_watch_check,
GSourceFuncs g_timeout_funcs =
{
- g_timeout_prepare,
- g_timeout_check,
+ NULL, /* prepare */
+ NULL, /* check */
g_timeout_dispatch,
NULL
};
void
g_main_context_unref (GMainContext *context)
{
+ GSourceIter iter;
GSource *source;
+ GList *sl_iter;
+ GSourceList *list;
+ gint i;
+
g_return_if_fail (context != NULL);
g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0);
main_context_list = g_slist_remove (main_context_list, context);
G_UNLOCK (main_context_list);
- source = context->source_list;
- while (source)
+ /* Free pending dispatches */
+ for (i = 0; i < context->pending_dispatches->len; i++)
+ g_source_unref_internal (context->pending_dispatches->pdata[i], context, FALSE);
+
+ /* g_source_iter_next() assumes the context is locked. */
+ LOCK_CONTEXT (context);
+ g_source_iter_init (&iter, context, TRUE);
+ while (g_source_iter_next (&iter, &source))
+ {
+ source->context = NULL;
+ g_source_destroy_internal (source, context, TRUE);
+ }
+ UNLOCK_CONTEXT (context);
+
+ for (sl_iter = context->source_lists; sl_iter; sl_iter = sl_iter->next)
{
- GSource *next = source->next;
- g_source_destroy_internal (source, context, FALSE);
- source = next;
+ list = sl_iter->data;
+ g_slice_free (GSourceList, list);
}
+ g_list_free (context->source_lists);
+
+ g_hash_table_destroy (context->sources);
g_mutex_clear (&context->mutex);
g_free (context);
}
-#ifdef G_OS_UNIX
-static void
-g_main_context_forked (void)
+/* Helper function used by mainloop/overflow test.
+ */
+GMainContext *
+g_main_context_new_with_next_id (guint next_id)
{
- g_main_context_fork_detected = TRUE;
+ GMainContext *ret = g_main_context_new ();
+
+ ret->next_id = next_id;
+
+ return ret;
}
-#endif
/**
* g_main_context_new:
*
* Creates a new #GMainContext structure.
*
- * Return value: the new #GMainContext
+ * Returns: the new #GMainContext
**/
GMainContext *
g_main_context_new (void)
_g_main_poll_debug = TRUE;
#endif
-#ifdef G_OS_UNIX
- pthread_atfork (NULL, NULL, g_main_context_forked);
-#endif
-
g_once_init_leave (&initialised, TRUE);
}
g_mutex_init (&context->mutex);
g_cond_init (&context->cond);
+ context->sources = g_hash_table_new (NULL, NULL);
context->owner = NULL;
context->waiters = NULL;
context->next_id = 1;
- context->source_list = NULL;
+ context->source_lists = NULL;
context->poll_func = g_poll;
* specified, and corresponds to the "main" main loop. See also
* g_main_context_get_thread_default().
*
- * Return value: (transfer none): the global default main context.
+ * Returns: (transfer none): the global default main context.
**/
GMainContext *
g_main_context_default (void)
}
static void
-free_context_stack (gpointer data)
+free_context (gpointer data)
{
- GQueue *stack = data;
- GMainContext *context;
+ GMainContext *context = data;
- while (!g_queue_is_empty (stack))
- {
- context = g_queue_pop_head (stack);
- g_main_context_release (context);
- if (context)
- g_main_context_unref (context);
- }
- g_queue_free (stack);
+ g_main_context_release (context);
+ if (context)
+ g_main_context_unref (context);
+}
+
+static void
+free_context_stack (gpointer data)
+{
+ g_queue_free_full((GQueue *) data, (GDestroyNotify) free_context);
}
static GPrivate thread_context_stack = G_PRIVATE_INIT (free_context_stack);
/**
* g_main_context_push_thread_default:
- * @context: a #GMainContext, or %NULL for the global default context
+ * @context: (allow-none): a #GMainContext, or %NULL for the global default context
*
* Acquires @context and sets it as the thread-default context for the
* current thread. This will cause certain asynchronous operations
- * (such as most <link linkend="gio">gio</link>-based I/O) which are
+ * (such as most [gio][gio]-based I/O) which are
* started in this thread to run under @context and deliver their
* results to its main loop, rather than running under the global
* default context in the main thread. Note that calling this function
- * changes the context returned by
- * g_main_context_get_thread_default(), <emphasis>not</emphasis> the
- * one returned by g_main_context_default(), so it does not affect the
- * context used by functions like g_idle_add().
+ * changes the context returned by g_main_context_get_thread_default(),
+ * not the one returned by g_main_context_default(), so it does not affect
+ * the context used by functions like g_idle_add().
*
* Normally you would call this function shortly after creating a new
* thread, passing it a #GMainContext which will be run by a
/**
* g_main_context_pop_thread_default:
- * @context: a #GMainContext object, or %NULL
+ * @context: (allow-none): a #GMainContext object, or %NULL
*
* Pops @context off the thread-default context stack (verifying that
* it was on the top of the stack).
* operations that want to be able to be run in contexts other than
* the default one should call this method or
* g_main_context_ref_thread_default() to get a #GMainContext to add
- * their #GSource<!-- -->s to. (Note that even in single-threaded
+ * their #GSources to. (Note that even in single-threaded
* programs applications may sometimes want to temporarily push a
* non-default context, so it is not safe to assume that this will
* always return %NULL if you are running in the default thread.)
* Creates a new #GSource structure. The size is specified to
* allow creating structures derived from #GSource that contain
* additional data. The size passed in must be at least
- * <literal>sizeof (GSource)</literal>.
+ * `sizeof (GSource)`.
*
* The source will not initially be associated with any #GMainContext
* and must be added to one with g_source_attach() before it will be
* executed.
*
- * Return value: the newly-created #GSource.
+ * Returns: the newly-created #GSource.
**/
GSource *
g_source_new (GSourceFuncs *source_funcs,
g_return_val_if_fail (struct_size >= sizeof (GSource), NULL);
source = (GSource*) g_malloc0 (struct_size);
-
+ source->priv = g_slice_new0 (GSourcePrivate);
source->source_funcs = source_funcs;
source->ref_count = 1;
source->flags = G_HOOK_FLAG_ACTIVE;
+ source->priv->ready_time = -1;
+
/* NULL/0 initialization for all other fields */
return source;
}
+/* Holds context's lock */
+static void
+g_source_iter_init (GSourceIter *iter,
+ GMainContext *context,
+ gboolean may_modify)
+{
+ iter->context = context;
+ iter->current_list = NULL;
+ iter->source = NULL;
+ iter->may_modify = may_modify;
+}
+
+/* Holds context's lock */
+static gboolean
+g_source_iter_next (GSourceIter *iter, GSource **source)
+{
+ GSource *next_source;
+
+ if (iter->source)
+ next_source = iter->source->next;
+ else
+ next_source = NULL;
+
+ if (!next_source)
+ {
+ if (iter->current_list)
+ iter->current_list = iter->current_list->next;
+ else
+ iter->current_list = iter->context->source_lists;
+
+ if (iter->current_list)
+ {
+ GSourceList *source_list = iter->current_list->data;
+
+ next_source = source_list->head;
+ }
+ }
+
+ /* Note: unreffing iter->source could potentially cause its
+ * GSourceList to be removed from source_lists (if iter->source is
+ * the only source in its list, and it is destroyed), so we have to
+ * keep it reffed until after we advance iter->current_list, above.
+ */
+
+ if (iter->source && iter->may_modify)
+ SOURCE_UNREF (iter->source, iter->context);
+ iter->source = next_source;
+ if (iter->source && iter->may_modify)
+ iter->source->ref_count++;
+
+ *source = iter->source;
+ return *source != NULL;
+}
+
+/* Holds context's lock. Only necessary to call if you broke out of
+ * the g_source_iter_next() loop early.
+ */
+static void
+g_source_iter_clear (GSourceIter *iter)
+{
+ if (iter->source && iter->may_modify)
+ {
+ SOURCE_UNREF (iter->source, iter->context);
+ iter->source = NULL;
+ }
+}
+
+/* Holds context's lock
+ */
+static GSourceList *
+find_source_list_for_priority (GMainContext *context,
+ gint priority,
+ gboolean create)
+{
+ GList *iter, *last;
+ GSourceList *source_list;
+
+ last = NULL;
+ for (iter = context->source_lists; iter != NULL; last = iter, iter = iter->next)
+ {
+ source_list = iter->data;
+
+ if (source_list->priority == priority)
+ return source_list;
+
+ if (source_list->priority > priority)
+ {
+ if (!create)
+ return NULL;
+
+ source_list = g_slice_new0 (GSourceList);
+ source_list->priority = priority;
+ context->source_lists = g_list_insert_before (context->source_lists,
+ iter,
+ source_list);
+ return source_list;
+ }
+ }
+
+ if (!create)
+ return NULL;
+
+ source_list = g_slice_new0 (GSourceList);
+ source_list->priority = priority;
+
+ if (!last)
+ context->source_lists = g_list_append (NULL, source_list);
+ else
+ {
+ /* This just appends source_list to the end of
+ * context->source_lists without having to walk the list again.
+ */
+ last = g_list_append (last, source_list);
+ }
+ return source_list;
+}
+
/* Holds context's lock
*/
static void
-g_source_list_add (GSource *source,
- GMainContext *context)
+source_add_to_context (GSource *source,
+ GMainContext *context)
{
- GSource *tmp_source, *last_source;
-
- if (source->priv && source->priv->parent_source)
+ GSourceList *source_list;
+ GSource *prev, *next;
+
+ source_list = find_source_list_for_priority (context, source->priority, TRUE);
+
+ if (source->priv->parent_source)
{
+ g_assert (source_list->head != NULL);
+
/* Put the source immediately before its parent */
- tmp_source = source->priv->parent_source;
- last_source = source->priv->parent_source->prev;
+ prev = source->priv->parent_source->prev;
+ next = source->priv->parent_source;
}
else
{
- last_source = NULL;
- tmp_source = context->source_list;
- while (tmp_source && tmp_source->priority <= source->priority)
- {
- last_source = tmp_source;
- tmp_source = tmp_source->next;
- }
+ prev = source_list->tail;
+ next = NULL;
}
- source->next = tmp_source;
- if (tmp_source)
- tmp_source->prev = source;
+ source->next = next;
+ if (next)
+ next->prev = source;
+ else
+ source_list->tail = source;
- source->prev = last_source;
- if (last_source)
- last_source->next = source;
+ source->prev = prev;
+ if (prev)
+ prev->next = source;
else
- context->source_list = source;
+ source_list->head = source;
}
/* Holds context's lock
*/
static void
-g_source_list_remove (GSource *source,
- GMainContext *context)
+source_remove_from_context (GSource *source,
+ GMainContext *context)
{
+ GSourceList *source_list;
+
+ source_list = find_source_list_for_priority (context, source->priority, FALSE);
+ g_return_if_fail (source_list != NULL);
+
if (source->prev)
source->prev->next = source->next;
else
- context->source_list = source->next;
+ source_list->head = source->next;
if (source->next)
source->next->prev = source->prev;
+ else
+ source_list->tail = source->prev;
source->prev = NULL;
source->next = NULL;
+
+ if (source_list->head == NULL)
+ {
+ context->source_lists = g_list_remove (context->source_lists, source_list);
+ g_slice_free (GSourceList, source_list);
+ }
}
static guint
g_source_attach_unlocked (GSource *source,
- GMainContext *context)
+ GMainContext *context,
+ gboolean do_wakeup)
{
- guint result = 0;
GSList *tmp_list;
+ guint id;
- source->context = context;
- result = source->source_id = context->next_id++;
+ /* The counter may have wrapped, so we must ensure that we do not
+ * reuse the source id of an existing source.
+ */
+ do
+ id = context->next_id++;
+ while (id == 0 || g_hash_table_contains (context->sources, GUINT_TO_POINTER (id)));
+ source->context = context;
+ source->source_id = id;
source->ref_count++;
- g_source_list_add (source, context);
- tmp_list = source->poll_fds;
- while (tmp_list)
+ g_hash_table_insert (context->sources, GUINT_TO_POINTER (id), source);
+
+ source_add_to_context (source, context);
+
+ if (!SOURCE_BLOCKED (source))
{
- g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
- tmp_list = tmp_list->next;
+ tmp_list = source->poll_fds;
+ while (tmp_list)
+ {
+ g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
+ tmp_list = tmp_list->next;
+ }
+
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data);
}
- if (source->priv)
+ tmp_list = source->priv->child_sources;
+ while (tmp_list)
{
- tmp_list = source->priv->child_sources;
- while (tmp_list)
- {
- g_source_attach_unlocked (tmp_list->data, context);
- tmp_list = tmp_list->next;
- }
+ g_source_attach_unlocked (tmp_list->data, context, FALSE);
+ tmp_list = tmp_list->next;
}
- return result;
+ /* If another thread has acquired the context, wake it up since it
+ * might be in poll() right now.
+ */
+ if (do_wakeup && context->owner && context->owner != G_THREAD_SELF)
+ g_wakeup_signal (context->wakeup);
+
+ return source->source_id;
}
/**
* g_source_attach:
* @source: a #GSource
- * @context: a #GMainContext (if %NULL, the default context will be used)
+ * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
*
* Adds a #GSource to a @context so that it will be executed within
* that context. Remove it by calling g_source_destroy().
*
- * Return value: the ID (greater than 0) for the source within the
+ * Returns: the ID (greater than 0) for the source within the
* #GMainContext.
**/
guint
g_return_val_if_fail (source->context == NULL, 0);
g_return_val_if_fail (!SOURCE_DESTROYED (source), 0);
+ TRACE (GLIB_MAIN_SOURCE_ATTACH (g_source_get_name (source)));
+
if (!context)
context = g_main_context_default ();
LOCK_CONTEXT (context);
- result = g_source_attach_unlocked (source, context);
-
- /* If another thread has acquired the context, wake it up since it
- * might be in poll() right now.
- */
- if (context->owner && context->owner != G_THREAD_SELF)
- g_wakeup_signal (context->wakeup);
+ result = g_source_attach_unlocked (source, context, TRUE);
UNLOCK_CONTEXT (context);
GMainContext *context,
gboolean have_lock)
{
+ TRACE (GLIB_MAIN_SOURCE_DESTROY (g_source_get_name (source)));
+
if (!have_lock)
LOCK_CONTEXT (context);
g_main_context_remove_poll_unlocked (context, tmp_list->data);
tmp_list = tmp_list->next;
}
- }
- if (source->priv && source->priv->child_sources)
- {
- /* This is safe because even if a child_source finalizer or
- * closure notify tried to modify source->priv->child_sources
- * from outside the lock, it would fail since
- * SOURCE_DESTROYED(source) is now TRUE.
- */
- tmp_list = source->priv->child_sources;
- while (tmp_list)
- {
- g_source_destroy_internal (tmp_list->data, context, TRUE);
- g_source_unref_internal (tmp_list->data, context, TRUE);
- tmp_list = tmp_list->next;
- }
- g_slist_free (source->priv->child_sources);
- source->priv->child_sources = NULL;
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ g_main_context_remove_poll_unlocked (context, tmp_list->data);
}
+
+ while (source->priv->child_sources)
+ g_child_source_remove_internal (source->priv->child_sources->data, context);
+
+ if (source->priv->parent_source)
+ g_child_source_remove_internal (source, context);
g_source_unref_internal (source, context, TRUE);
}
*
* Removes a source from its #GMainContext, if any, and mark it as
* destroyed. The source cannot be subsequently added to another
- * context.
+ * context. It is safe to call this on sources which have already been
+ * removed from their context.
**/
void
g_source_destroy (GSource *source)
* context. The reverse
* mapping from ID to source is done by g_main_context_find_source_by_id().
*
- * Return value: the ID (greater than 0) for the source
+ * Returns: the ID (greater than 0) for the source
**/
guint
g_source_get_id (GSource *source)
* @source: a #GSource
*
* Gets the #GMainContext with which the source is associated.
- * Calling this function on a destroyed source is an error.
+ *
+ * You can call this on a source that has been destroyed, provided
+ * that the #GMainContext it was attached to still exists (in which
+ * case it will return that #GMainContext). In particular, you can
+ * always call this function on the source returned from
+ * g_main_current_source(). But calling this function on a source
+ * whose #GMainContext has been destroyed is an error.
*
- * Return value: (transfer none): the #GMainContext with which the
+ * Returns: (transfer none) (allow-none): the #GMainContext with which the
* source is associated, or %NULL if the context has not
* yet been added to a source.
**/
GMainContext *
g_source_get_context (GSource *source)
{
- g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
+ g_return_val_if_fail (source->context != NULL || !SOURCE_DESTROYED (source), NULL);
return source->context;
}
* @source:a #GSource
* @fd: a #GPollFD structure holding information about a file
* descriptor to watch.
- *
+ *
* Adds a file descriptor to the set of file descriptors polled for
* this source. This is usually combined with g_source_new() to add an
* event source. The event source's check function will typically test
* the @revents field in the #GPollFD struct and return %TRUE if events need
* to be processed.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * Using this API forces the linear scanning of event sources on each
+ * main loop iteration. Newly-written event sources should try to use
+ * g_source_add_unix_fd() instead of this API.
**/
void
g_source_add_poll (GSource *source,
*
* Removes a file descriptor from the set of file descriptors polled for
* this source.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
**/
void
g_source_remove_poll (GSource *source,
* @source will hold a reference on @child_source while @child_source
* is attached to it.
*
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
* Since: 2.28
**/
void
g_return_if_fail (!SOURCE_DESTROYED (source));
g_return_if_fail (!SOURCE_DESTROYED (child_source));
g_return_if_fail (child_source->context == NULL);
- g_return_if_fail (child_source->priv == NULL || child_source->priv->parent_source == NULL);
+ g_return_if_fail (child_source->priv->parent_source == NULL);
context = source->context;
if (context)
LOCK_CONTEXT (context);
- if (!source->priv)
- source->priv = g_slice_new0 (GSourcePrivate);
- if (!child_source->priv)
- child_source->priv = g_slice_new0 (GSourcePrivate);
-
source->priv->child_sources = g_slist_prepend (source->priv->child_sources,
g_source_ref (child_source));
child_source->priv->parent_source = source;
- g_source_set_priority_unlocked (child_source, context, source->priority);
+ g_source_set_priority_unlocked (child_source, NULL, source->priority);
+ if (SOURCE_BLOCKED (source))
+ block_source (child_source);
if (context)
{
+ g_source_attach_unlocked (child_source, context, TRUE);
UNLOCK_CONTEXT (context);
- g_source_attach (child_source, context);
}
}
+static void
+g_child_source_remove_internal (GSource *child_source,
+ GMainContext *context)
+{
+ GSource *parent_source = child_source->priv->parent_source;
+
+ parent_source->priv->child_sources =
+ g_slist_remove (parent_source->priv->child_sources, child_source);
+ child_source->priv->parent_source = NULL;
+
+ g_source_destroy_internal (child_source, context, TRUE);
+ g_source_unref_internal (child_source, context, TRUE);
+}
+
/**
* g_source_remove_child_source:
* @source:a #GSource
*
* Detaches @child_source from @source and destroys it.
*
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
* Since: 2.28
**/
void
g_return_if_fail (source != NULL);
g_return_if_fail (child_source != NULL);
- g_return_if_fail (child_source->priv != NULL && child_source->priv->parent_source == source);
+ g_return_if_fail (child_source->priv->parent_source == source);
g_return_if_fail (!SOURCE_DESTROYED (source));
g_return_if_fail (!SOURCE_DESTROYED (child_source));
if (context)
LOCK_CONTEXT (context);
- source->priv->child_sources = g_slist_remove (source->priv->child_sources, child_source);
- g_source_destroy_internal (child_source, context, TRUE);
- g_source_unref_internal (child_source, context, TRUE);
+ g_child_source_remove_internal (child_source, context);
if (context)
UNLOCK_CONTEXT (context);
* @source: the source
* @func: a callback function
* @data: the data to pass to callback function
- * @notify: a function to call when @data is no longer in use, or %NULL.
+ * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
*
* Sets the callback function for a source. The callback for a source is
* called from the source's dispatch function.
{
GSList *tmp_list;
- source->priority = priority;
+ g_return_if_fail (source->priv->parent_source == NULL ||
+ source->priv->parent_source->priority == priority);
if (context)
{
/* Remove the source from the context's source and then
- * add it back so it is sorted in the correct place
+ * add it back after so it is sorted in the correct place
*/
- g_source_list_remove (source, source->context);
- g_source_list_add (source, source->context);
+ source_remove_from_context (source, source->context);
+ }
+
+ source->priority = priority;
+
+ if (context)
+ {
+ source_add_to_context (source, source->context);
if (!SOURCE_BLOCKED (source))
{
tmp_list = tmp_list->next;
}
+
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ {
+ g_main_context_remove_poll_unlocked (context, tmp_list->data);
+ g_main_context_add_poll_unlocked (context, priority, tmp_list->data);
+ }
}
}
- if (source->priv && source->priv->child_sources)
+ if (source->priv->child_sources)
{
tmp_list = source->priv->child_sources;
while (tmp_list)
* source will be dispatched if it is ready to be dispatched and no
* sources at a higher (numerically smaller) priority are ready to be
* dispatched.
+ *
+ * A child source always has the same priority as its parent. It is not
+ * permitted to change the priority of a source once it has been added
+ * as a child of another source.
**/
void
g_source_set_priority (GSource *source,
GMainContext *context;
g_return_if_fail (source != NULL);
+ g_return_if_fail (source->priv->parent_source == NULL);
context = source->context;
*
* Gets the priority of a source.
*
- * Return value: the priority of the source
+ * Returns: the priority of the source
**/
gint
g_source_get_priority (GSource *source)
}
/**
+ * g_source_set_ready_time:
+ * @source: a #GSource
+ * @ready_time: the monotonic time at which the source will be ready,
+ * 0 for "immediately", -1 for "never"
+ *
+ * Sets a #GSource to be dispatched when the given monotonic time is
+ * reached (or passed). If the monotonic time is in the past (as it
+ * always will be if @ready_time is 0) then the source will be
+ * dispatched immediately.
+ *
+ * If @ready_time is -1 then the source is never woken up on the basis
+ * of the passage of time.
+ *
+ * Dispatching the source does not reset the ready time. You should do
+ * so yourself, from the source dispatch function.
+ *
+ * Note that if you have a pair of sources where the ready time of one
+ * suggests that it will be delivered first but the priority for the
+ * other suggests that it would be delivered first, and the ready time
+ * for both sources is reached during the same main context iteration
+ * then the order of dispatch is undefined.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * Since: 2.36
+ **/
+void
+g_source_set_ready_time (GSource *source,
+ gint64 ready_time)
+{
+ GMainContext *context;
+
+ g_return_if_fail (source != NULL);
+ g_return_if_fail (source->ref_count > 0);
+
+ if (source->priv->ready_time == ready_time)
+ return;
+
+ context = source->context;
+
+ if (context)
+ LOCK_CONTEXT (context);
+
+ source->priv->ready_time = ready_time;
+
+ if (context)
+ {
+ /* Quite likely that we need to change the timeout on the poll */
+ if (!SOURCE_BLOCKED (source))
+ g_wakeup_signal (context->wakeup);
+ UNLOCK_CONTEXT (context);
+ }
+}
+
+/**
+ * g_source_get_ready_time:
+ * @source: a #GSource
+ *
+ * Gets the "ready time" of @source, as set by
+ * g_source_set_ready_time().
+ *
+ * Any time before the current monotonic time (including 0) is an
+ * indication that the source will fire immediately.
+ *
+ * Returns: the monotonic ready time, -1 for "never"
+ **/
+gint64
+g_source_get_ready_time (GSource *source)
+{
+ g_return_val_if_fail (source != NULL, -1);
+
+ return source->priv->ready_time;
+}
+
+/**
* g_source_set_can_recurse:
* @source: a #GSource
* @can_recurse: whether recursion is allowed for this source
* Checks whether a source is allowed to be called recursively.
* see g_source_set_can_recurse().
*
- * Return value: whether recursion is allowed.
+ * Returns: whether recursion is allowed.
**/
gboolean
g_source_get_can_recurse (GSource *source)
* The name may be #NULL if it has never been set with
* g_source_set_name().
*
- * Return value: the name of the source
+ * Returns: the name of the source
* Since: 2.26
**/
const char *
* This is a convenience utility to set source names from the return
* value of g_idle_add(), g_timeout_add(), etc.
*
+ * It is a programmer error to attempt to set the name of a non-existent
+ * source.
+ *
+ * More specifically: source IDs can be reissued after a source has been
+ * destroyed and therefore it is never valid to use this function with a
+ * source ID which may have already been removed. An example is when
+ * scheduling an idle to run in another thread with g_idle_add(): the
+ * idle may already have run and been removed by the time this function
+ * is called on its (now invalid) source ID. This source ID may have
+ * been reissued, leading to the operation being performed against the
+ * wrong source.
+ *
* Since: 2.26
**/
void
*
* Increases the reference count on a source by one.
*
- * Return value: @source
+ * Returns: @source
**/
GSource *
g_source_ref (GSource *source)
{
if (!SOURCE_DESTROYED (source))
g_warning (G_STRLOC ": ref_count == 0, but source was still attached to a context!");
- g_source_list_remove (source, context);
+ source_remove_from_context (source, context);
+
+ g_hash_table_remove (context->sources, GUINT_TO_POINTER (source->source_id));
}
if (source->source_funcs->finalize)
g_slist_free (source->poll_fds);
source->poll_fds = NULL;
- if (source->priv)
- {
- g_slice_free (GSourcePrivate, source->priv);
- source->priv = NULL;
- }
+ g_slist_free_full (source->priv->fds, g_free);
+
+ g_slice_free (GSourcePrivate, source->priv);
+ source->priv = NULL;
g_free (source);
}
/**
* g_main_context_find_source_by_id:
- * @context: a #GMainContext (if %NULL, the default context will be used)
- * @source_id: the source ID, as returned by g_source_get_id().
- *
+ * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
+ * @source_id: the source ID, as returned by g_source_get_id().
+ *
* Finds a #GSource given a pair of context and ID.
- *
- * Return value: (transfer none): the #GSource if found, otherwise, %NULL
+ *
+ * It is a programmer error to attempt to lookup a non-existent source.
+ *
+ * More specifically: source IDs can be reissued after a source has been
+ * destroyed and therefore it is never valid to use this function with a
+ * source ID which may have already been removed. An example is when
+ * scheduling an idle to run in another thread with g_idle_add(): the
+ * idle may already have run and been removed by the time this function
+ * is called on its (now invalid) source ID. This source ID may have
+ * been reissued, leading to the operation being performed against the
+ * wrong source.
+ *
+ * Returns: (transfer none): the #GSource
**/
GSource *
g_main_context_find_source_by_id (GMainContext *context,
- guint source_id)
+ guint source_id)
{
GSource *source;
-
+
g_return_val_if_fail (source_id > 0, NULL);
if (context == NULL)
context = g_main_context_default ();
-
- LOCK_CONTEXT (context);
-
- source = context->source_list;
- while (source)
- {
- if (!SOURCE_DESTROYED (source) &&
- source->source_id == source_id)
- break;
- source = source->next;
- }
+ LOCK_CONTEXT (context);
+ source = g_hash_table_lookup (context->sources, GUINT_TO_POINTER (source_id));
UNLOCK_CONTEXT (context);
+ if (source && SOURCE_DESTROYED (source))
+ source = NULL;
+
return source;
}
/**
* g_main_context_find_source_by_funcs_user_data:
- * @context: a #GMainContext (if %NULL, the default context will be used).
+ * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used).
* @funcs: the @source_funcs passed to g_source_new().
* @user_data: the user data from the callback.
*
* multiple sources exist with the same source function and user data,
* the first one found will be returned.
*
- * Return value: (transfer none): the source, if one was found, otherwise %NULL
+ * Returns: (transfer none): the source, if one was found, otherwise %NULL
**/
GSource *
g_main_context_find_source_by_funcs_user_data (GMainContext *context,
GSourceFuncs *funcs,
gpointer user_data)
{
+ GSourceIter iter;
GSource *source;
g_return_val_if_fail (funcs != NULL, NULL);
LOCK_CONTEXT (context);
- source = context->source_list;
- while (source)
+ g_source_iter_init (&iter, context, FALSE);
+ while (g_source_iter_next (&iter, &source))
{
if (!SOURCE_DESTROYED (source) &&
source->source_funcs == funcs &&
if (callback_data == user_data)
break;
}
- source = source->next;
}
+ g_source_iter_clear (&iter);
UNLOCK_CONTEXT (context);
* multiple sources exist with the same user data, the first
* one found will be returned.
*
- * Return value: (transfer none): the source, if one was found, otherwise %NULL
+ * Returns: (transfer none): the source, if one was found, otherwise %NULL
**/
GSource *
g_main_context_find_source_by_user_data (GMainContext *context,
gpointer user_data)
{
+ GSourceIter iter;
GSource *source;
if (context == NULL)
LOCK_CONTEXT (context);
- source = context->source_list;
- while (source)
+ g_source_iter_init (&iter, context, FALSE);
+ while (g_source_iter_next (&iter, &source))
{
if (!SOURCE_DESTROYED (source) &&
source->callback_funcs)
if (callback_data == user_data)
break;
}
- source = source->next;
}
+ g_source_iter_clear (&iter);
UNLOCK_CONTEXT (context);
/**
* g_source_remove:
* @tag: the ID of the source to remove.
- *
- * Removes the source with the given id from the default main context.
- * The id of
- * a #GSource is given by g_source_get_id(), or will be returned by the
- * functions g_source_attach(), g_idle_add(), g_idle_add_full(),
- * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(),
- * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full().
+ *
+ * Removes the source with the given id from the default main context.
+ *
+ * The id of a #GSource is given by g_source_get_id(), or will be
+ * returned by the functions g_source_attach(), g_idle_add(),
+ * g_idle_add_full(), g_timeout_add(), g_timeout_add_full(),
+ * g_child_watch_add(), g_child_watch_add_full(), g_io_add_watch(), and
+ * g_io_add_watch_full().
*
* See also g_source_destroy(). You must use g_source_destroy() for sources
* added to a non-default main context.
*
- * Return value: %TRUE if the source was found and removed.
+ * It is a programmer error to attempt to remove a non-existent source.
+ *
+ * More specifically: source IDs can be reissued after a source has been
+ * destroyed and therefore it is never valid to use this function with a
+ * source ID which may have already been removed. An example is when
+ * scheduling an idle to run in another thread with g_idle_add(): the
+ * idle may already have run and been removed by the time this function
+ * is called on its (now invalid) source ID. This source ID may have
+ * been reissued, leading to the operation being performed against the
+ * wrong source.
+ *
+ * Returns: For historical reasons, this function always returns %TRUE
**/
gboolean
g_source_remove (guint tag)
{
GSource *source;
-
+
g_return_val_if_fail (tag > 0, FALSE);
source = g_main_context_find_source_by_id (NULL, tag);
if (source)
g_source_destroy (source);
+ else
+ g_critical ("Source ID %u was not found when attempting to remove it", tag);
return source != NULL;
}
* data for the callback. If multiple sources exist with the same user
* data, only one will be destroyed.
*
- * Return value: %TRUE if a source was found and removed.
+ * Returns: %TRUE if a source was found and removed.
**/
gboolean
g_source_remove_by_user_data (gpointer user_data)
* source functions and user data. If multiple sources exist with the
* same source functions and user data, only one will be destroyed.
*
- * Return value: %TRUE if a source was found and removed.
+ * Returns: %TRUE if a source was found and removed.
**/
gboolean
g_source_remove_by_funcs_user_data (GSourceFuncs *funcs,
return FALSE;
}
+#ifdef G_OS_UNIX
+/**
+ * g_source_add_unix_fd:
+ * @source: a #GSource
+ * @fd: the fd to monitor
+ * @events: an event mask
+ *
+ * Monitors @fd for the IO events in @events.
+ *
+ * The tag returned by this function can be used to remove or modify the
+ * monitoring of the fd using g_source_remove_unix_fd() or
+ * g_source_modify_unix_fd().
+ *
+ * It is not necessary to remove the fd before destroying the source; it
+ * will be cleaned up automatically.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * As the name suggests, this function is not available on Windows.
+ *
+ * Returns: an opaque tag
+ *
+ * Since: 2.36
+ **/
+gpointer
+g_source_add_unix_fd (GSource *source,
+ gint fd,
+ GIOCondition events)
+{
+ GMainContext *context;
+ GPollFD *poll_fd;
+
+ g_return_val_if_fail (source != NULL, NULL);
+ g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL);
+
+ poll_fd = g_new (GPollFD, 1);
+ poll_fd->fd = fd;
+ poll_fd->events = events;
+ poll_fd->revents = 0;
+
+ context = source->context;
+
+ if (context)
+ LOCK_CONTEXT (context);
+
+ source->priv->fds = g_slist_prepend (source->priv->fds, poll_fd);
+
+ if (context)
+ {
+ if (!SOURCE_BLOCKED (source))
+ g_main_context_add_poll_unlocked (context, source->priority, poll_fd);
+ UNLOCK_CONTEXT (context);
+ }
+
+ return poll_fd;
+}
+
+/**
+ * g_source_modify_unix_fd:
+ * @source: a #GSource
+ * @tag: the tag from g_source_add_unix_fd()
+ * @new_events: the new event mask to watch
+ *
+ * Updates the event mask to watch for the fd identified by @tag.
+ *
+ * @tag is the tag returned from g_source_add_unix_fd().
+ *
+ * If you want to remove a fd, don't set its event mask to zero.
+ * Instead, call g_source_remove_unix_fd().
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * As the name suggests, this function is not available on Windows.
+ *
+ * Since: 2.36
+ **/
+void
+g_source_modify_unix_fd (GSource *source,
+ gpointer tag,
+ GIOCondition new_events)
+{
+ GMainContext *context;
+ GPollFD *poll_fd;
+
+ g_return_if_fail (source != NULL);
+ g_return_if_fail (g_slist_find (source->priv->fds, tag));
+
+ context = source->context;
+ poll_fd = tag;
+
+ poll_fd->events = new_events;
+
+ if (context)
+ g_main_context_wakeup (context);
+}
+
+/**
+ * g_source_remove_unix_fd:
+ * @source: a #GSource
+ * @tag: the tag from g_source_add_unix_fd()
+ *
+ * Reverses the effect of a previous call to g_source_add_unix_fd().
+ *
+ * You only need to call this if you want to remove an fd from being
+ * watched while keeping the same source around. In the normal case you
+ * will just want to destroy the source.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * As the name suggests, this function is not available on Windows.
+ *
+ * Since: 2.36
+ **/
+void
+g_source_remove_unix_fd (GSource *source,
+ gpointer tag)
+{
+ GMainContext *context;
+ GPollFD *poll_fd;
+
+ g_return_if_fail (source != NULL);
+ g_return_if_fail (g_slist_find (source->priv->fds, tag));
+
+ context = source->context;
+ poll_fd = tag;
+
+ if (context)
+ LOCK_CONTEXT (context);
+
+ source->priv->fds = g_slist_remove (source->priv->fds, poll_fd);
+
+ if (context)
+ {
+ if (!SOURCE_BLOCKED (source))
+ g_main_context_remove_poll_unlocked (context, poll_fd);
+
+ UNLOCK_CONTEXT (context);
+ }
+
+ g_free (poll_fd);
+}
+
+/**
+ * g_source_query_unix_fd:
+ * @source: a #GSource
+ * @tag: the tag from g_source_add_unix_fd()
+ *
+ * Queries the events reported for the fd corresponding to @tag on
+ * @source during the last poll.
+ *
+ * The return value of this function is only defined when the function
+ * is called from the check or dispatch functions for @source.
+ *
+ * This API is only intended to be used by implementations of #GSource.
+ * Do not call this API on a #GSource that you did not create.
+ *
+ * As the name suggests, this function is not available on Windows.
+ *
+ * Returns: the conditions reported on the fd
+ *
+ * Since: 2.36
+ **/
+GIOCondition
+g_source_query_unix_fd (GSource *source,
+ gpointer tag)
+{
+ GPollFD *poll_fd;
+
+ g_return_val_if_fail (source != NULL, 0);
+ g_return_val_if_fail (g_slist_find (source->priv->fds, tag), 0);
+
+ poll_fd = tag;
+
+ return poll_fd->revents;
+}
+#endif /* G_OS_UNIX */
+
/**
* g_get_current_time:
* @result: #GTimeVal structure in which to store current time.
/**
* g_get_monotonic_time:
*
- * Queries the system monotonic time, if available.
- *
- * On POSIX systems with clock_gettime() and %CLOCK_MONOTONIC this call
- * is a very shallow wrapper for that. Otherwise, we make a best effort
- * that probably involves returning the wall clock time (with at least
- * microsecond accuracy, subject to the limitations of the OS kernel).
+ * Queries the system monotonic time.
*
- * It's important to note that POSIX %CLOCK_MONOTONIC does not count
- * time spent while the machine is suspended.
+ * The monotonic clock will always increase and doesn't suffer
+ * discontinuities when the user (or NTP) changes the system time. It
+ * may or may not continue to tick during times where the machine is
+ * suspended.
*
- * On Windows, "limitations of the OS kernel" is a rather substantial
- * statement. Depending on the configuration of the system, the wall
- * clock time is updated as infrequently as 64 times a second (which
- * is approximately every 16ms).
+ * We try to use the clock that corresponds as closely as possible to
+ * the passage of time as measured by system calls such as poll() but it
+ * may not always be possible to do this.
*
* Returns: the monotonic time, in microseconds
*
* Since: 2.28
**/
+#if defined (G_OS_WIN32)
+static ULONGLONG (*g_GetTickCount64) (void) = NULL;
+static guint32 g_win32_tick_epoch = 0;
+
+void
+g_clock_win32_init (void)
+{
+ HMODULE kernel32;
+
+ g_GetTickCount64 = NULL;
+ kernel32 = GetModuleHandle ("KERNEL32.DLL");
+ if (kernel32 != NULL)
+ g_GetTickCount64 = (void *) GetProcAddress (kernel32, "GetTickCount64");
+ g_win32_tick_epoch = ((guint32)GetTickCount()) >> 31;
+}
+
+gint64
+g_get_monotonic_time (void)
+{
+ guint64 ticks;
+ guint32 ticks32;
+
+ /* There are four sources for the monotonic time on Windows:
+ *
+ * Three are based on a (1 msec accuracy, but only read periodically) clock chip:
+ * - GetTickCount (GTC)
+ * 32bit msec counter, updated each ~15msec, wraps in ~50 days
+ * - GetTickCount64 (GTC64)
+ * Same as GetTickCount, but extended to 64bit, so no wrap
+ * Only available in Vista or later
+ * - timeGetTime (TGT)
+ * similar to GetTickCount by default: 15msec, 50 day wrap.
+ * available in winmm.dll (thus known as the multimedia timers)
+ * However apps can raise the system timer clock frequency using timeBeginPeriod()
+ * increasing the accuracy up to 1 msec, at a cost in general system performance
+ * and battery use.
+ *
+ * One is based on high precision clocks:
+ * - QueryPrecisionCounter (QPC)
+ * This has much higher accuracy, but is not guaranteed monotonic, and
+ * has lots of complications like clock jumps and different times on different
+ * CPUs. It also has lower long term accuracy (i.e. it will drift compared to
+ * the low precision clocks.
+ *
+ * Additionally, the precision available in the timer-based wakeup such as
+ * MsgWaitForMultipleObjectsEx (which is what the mainloop is based on) is based
+ * on the TGT resolution, so by default it is ~15msec, but can be increased by apps.
+ *
+ * The QPC timer has too many issues to be used as is. The only way it could be used
+ * is to use it to interpolate the lower precision clocks. Firefox does something like
+ * this:
+ * https://bugzilla.mozilla.org/show_bug.cgi?id=363258
+ *
+ * However this seems quite complicated, so we're not doing this right now.
+ *
+ * The approach we take instead is to use the TGT timer, extending it to 64bit
+ * either by using the GTC64 value, or if that is not available, a process local
+ * time epoch that we increment when we detect a timer wrap (assumes that we read
+ * the time at least once every 50 days).
+ *
+ * This means that:
+ * - We have a globally consistent monotonic clock on Vista and later
+ * - We have a locally monotonic clock on XP
+ * - Apps that need higher precision in timeouts and clock reads can call
+ * timeBeginPeriod() to increase it as much as they want
+ */
+
+ if (g_GetTickCount64 != NULL)
+ {
+ guint32 ticks_as_32bit;
+
+ ticks = g_GetTickCount64 ();
+ ticks32 = timeGetTime();
+
+ /* GTC64 and TGT are sampled at different times, however they
+ * have the same base and source (msecs since system boot).
+ * They can differ by as much as -16 to +16 msecs.
+ * We can't just inject the low bits into the 64bit counter
+ * as one of the counters can have wrapped in 32bit space and
+ * the other not. Instead we calculate the signed difference
+ * in 32bit space and apply that difference to the 64bit counter.
+ */
+ ticks_as_32bit = (guint32)ticks;
+
+ /* We could do some 2's complement hack, but we play it safe */
+ if (ticks32 - ticks_as_32bit <= G_MAXINT32)
+ ticks += ticks32 - ticks_as_32bit;
+ else
+ ticks -= ticks_as_32bit - ticks32;
+ }
+ else
+ {
+ guint32 epoch;
+
+ epoch = g_atomic_int_get (&g_win32_tick_epoch);
+
+ /* Must read ticks after the epoch. Then we're guaranteed
+ * that the ticks value we read is higher or equal to any
+ * previous ones that lead to the writing of the epoch.
+ */
+ ticks32 = timeGetTime();
+
+ /* We store the MSB of the current time as the LSB
+ * of the epoch. Comparing these bits lets us detect when
+ * the 32bit counter has wrapped so we can increase the
+ * epoch.
+ *
+ * This will work as long as this function is called at
+ * least once every ~24 days, which is half the wrap time
+ * of a 32bit msec counter. I think this is pretty likely.
+ *
+ * Note that g_win32_tick_epoch is a process local state,
+ * so the monotonic clock will not be the same between
+ * processes.
+ */
+ if ((ticks32 >> 31) != (epoch & 1))
+ {
+ epoch++;
+ g_atomic_int_set (&g_win32_tick_epoch, epoch);
+ }
+
+
+ ticks = (guint64)ticks32 | ((guint64)epoch) << 31;
+ }
+
+ return ticks * 1000;
+}
+#elif defined(HAVE_MACH_MACH_TIME_H) /* Mac OS */
gint64
g_get_monotonic_time (void)
{
-#ifdef HAVE_CLOCK_GETTIME
- /* librt clock_gettime() is our first choice */
- struct timespec ts;
+ static mach_timebase_info_data_t timebase_info;
-#ifdef CLOCK_MONOTONIC
- clock_gettime (CLOCK_MONOTONIC, &ts);
-#else
- clock_gettime (CLOCK_REALTIME, &ts);
-#endif
+ if (timebase_info.denom == 0)
+ {
+ /* This is a fraction that we must use to scale
+ * mach_absolute_time() by in order to reach nanoseconds.
+ *
+ * We've only ever observed this to be 1/1, but maybe it could be
+ * 1000/1 if mach time is microseconds already, or 1/1000 if
+ * picoseconds. Try to deal nicely with that.
+ */
+ mach_timebase_info (&timebase_info);
- /* In theory monotonic time can have any epoch.
- *
- * glib presently assumes the following:
- *
- * 1) The epoch comes some time after the birth of Jesus of Nazareth, but
- * not more than 10000 years later.
- *
- * 2) The current time also falls sometime within this range.
- *
- * These two reasonable assumptions leave us with a maximum deviation from
- * the epoch of 10000 years, or 315569520000000000 seconds.
- *
- * If we restrict ourselves to this range then the number of microseconds
- * will always fit well inside the constraints of a int64 (by a factor of
- * about 29).
- *
- * If you actually hit the following assertion, probably you should file a
- * bug against your operating system for being excessively silly.
- **/
- g_assert (G_GINT64_CONSTANT (-315569520000000000) < ts.tv_sec &&
- ts.tv_sec < G_GINT64_CONSTANT (315569520000000000));
+ /* We actually want microseconds... */
+ if (timebase_info.numer % 1000 == 0)
+ timebase_info.numer /= 1000;
+ else
+ timebase_info.denom *= 1000;
- return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
+ /* We want to make the numer 1 to avoid having to multiply... */
+ if (timebase_info.denom % timebase_info.numer == 0)
+ {
+ timebase_info.denom /= timebase_info.numer;
+ timebase_info.numer = 1;
+ }
+ else
+ {
+ /* We could just multiply by timebase_info.numer below, but why
+ * bother for a case that may never actually exist...
+ *
+ * Plus -- performing the multiplication would risk integer
+ * overflow. If we ever actually end up in this situation, we
+ * should more carefully evaluate the correct course of action.
+ */
+ mach_timebase_info (&timebase_info); /* Get a fresh copy for a better message */
+ g_error ("Got weird mach timebase info of %d/%d. Please file a bug against GLib.",
+ timebase_info.numer, timebase_info.denom);
+ }
+ }
-#else /* !HAVE_CLOCK_GETTIME */
+ return mach_absolute_time () / timebase_info.denom;
+}
+#else
+gint64
+g_get_monotonic_time (void)
+{
+ struct timespec ts;
+ gint result;
- /* It may look like we are discarding accuracy on Windows (since its
- * current time is expressed in 100s of nanoseconds) but according to
- * many sources, the time is only updated 64 times per second, so
- * microsecond accuracy is more than enough.
- */
- GTimeVal tv;
+ result = clock_gettime (CLOCK_MONOTONIC, &ts);
- g_get_current_time (&tv);
+ if G_UNLIKELY (result != 0)
+ g_error ("GLib requires working CLOCK_MONOTONIC");
- return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec;
-#endif
+ return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000);
}
+#endif
static void
g_main_dispatch_free (gpointer dispatch)
* This function is useful in a situation like the following:
* Imagine an extremely simple "garbage collected" system.
*
- * |[
+ * |[<!-- language="C" -->
* static GList *free_list;
*
* gpointer
* doesn't work, since the idle function could be called from a
* recursive callback. This can be fixed by using g_main_depth()
*
- * |[
+ * |[<!-- language="C" -->
* gpointer
* allocate_memory (gsize size)
* {
* many things that the user could do. Instead, you can use the
* following techniques:
*
- * <orderedlist>
- * <listitem>
- * <para>
- * Use gtk_widget_set_sensitive() or modal dialogs to prevent
- * the user from interacting with elements while the main
- * loop is recursing.
- * </para>
- * </listitem>
- * <listitem>
- * <para>
- * Avoid main loop recursion in situations where you can't handle
- * arbitrary callbacks. Instead, structure your code so that you
- * simply return to the main loop and then get called again when
- * there is more work to do.
- * </para>
- * </listitem>
- * </orderedlist>
+ * 1. Use gtk_widget_set_sensitive() or modal dialogs to prevent
+ * the user from interacting with elements while the main
+ * loop is recursing.
*
- * Return value: The main loop recursion level in the current thread
- **/
+ * 2. Avoid main loop recursion in situations where you can't handle
+ * arbitrary callbacks. Instead, structure your code so that you
+ * simply return to the main loop and then get called again when
+ * there is more work to do.
+ *
+ * Returns: The main loop recursion level in the current thread
+ */
int
g_main_depth (void)
{
*
* Returns the currently firing source for this thread.
*
- * Return value: (transfer none): The currently firing source or %NULL.
+ * Returns: (transfer none): The currently firing source or %NULL.
*
* Since: 2.12
*/
g_main_current_source (void)
{
GMainDispatch *dispatch = get_dispatch ();
- return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL;
+ return dispatch->source;
}
/**
* from within idle handlers, but may have freed the object
* before the dispatch of your idle handler.
*
- * |[
+ * |[<!-- language="C" -->
* static gboolean
* idle_callback (gpointer data)
* {
* SomeWidget *self = data;
*
- * GDK_THREADS_ENTER (<!-- -->);
- * /<!-- -->* do stuff with self *<!-- -->/
+ * GDK_THREADS_ENTER ();
+ * // do stuff with self
* self->idle_id = 0;
- * GDK_THREADS_LEAVE (<!-- -->);
+ * GDK_THREADS_LEAVE ();
*
- * return FALSE;
+ * return G_SOURCE_REMOVE;
* }
*
* static void
* this particular problem, is to check to if the source
* has already been destroy within the callback.
*
- * |[
+ * |[<!-- language="C" -->
* static gboolean
* idle_callback (gpointer data)
* {
* GDK_THREADS_ENTER ();
* if (!g_source_is_destroyed (g_main_current_source ()))
* {
- * /<!-- -->* do stuff with self *<!-- -->/
+ * // do stuff with self
* }
* GDK_THREADS_LEAVE ();
*
* }
* ]|
*
- * Return value: %TRUE if the source has been destroyed
+ * Returns: %TRUE if the source has been destroyed
*
* Since: 2.12
*/
g_return_if_fail (!SOURCE_BLOCKED (source));
- tmp_list = source->poll_fds;
- while (tmp_list)
+ source->flags |= G_SOURCE_BLOCKED;
+
+ if (source->context)
{
- g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
- tmp_list = tmp_list->next;
+ tmp_list = source->poll_fds;
+ while (tmp_list)
+ {
+ g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
+ tmp_list = tmp_list->next;
+ }
+
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ g_main_context_remove_poll_unlocked (source->context, tmp_list->data);
+ }
+
+ if (source->priv && source->priv->child_sources)
+ {
+ tmp_list = source->priv->child_sources;
+ while (tmp_list)
+ {
+ block_source (tmp_list->data);
+ tmp_list = tmp_list->next;
+ }
}
}
unblock_source (GSource *source)
{
GSList *tmp_list;
-
- g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */
+
+ g_return_if_fail (SOURCE_BLOCKED (source)); /* Source already unblocked */
g_return_if_fail (!SOURCE_DESTROYED (source));
+ source->flags &= ~G_SOURCE_BLOCKED;
+
tmp_list = source->poll_fds;
while (tmp_list)
{
g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
tmp_list = tmp_list->next;
}
+
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ g_main_context_add_poll_unlocked (source->context, source->priority, tmp_list->data);
+
+ if (source->priv && source->priv->child_sources)
+ {
+ tmp_list = source->priv->child_sources;
+ while (tmp_list)
+ {
+ unblock_source (tmp_list->data);
+ tmp_list = tmp_list->next;
+ }
+ }
}
/* HOLDS: context's lock */
gboolean (*dispatch) (GSource *,
GSourceFunc,
gpointer);
- GSList current_source_link;
+ GSource *prev_source;
dispatch = source->source_funcs->dispatch;
cb_funcs = source->callback_funcs;
UNLOCK_CONTEXT (context);
- current->depth++;
- /* The on-stack allocation of the GSList is unconventional, but
- * we know that the lifetime of the link is bounded to this
- * function as the link is kept in a thread specific list and
- * not manipulated outside of this function and its descendants.
- * Avoiding the overhead of a g_slist_alloc() is useful as many
- * applications do little more than dispatch events.
- *
- * This is a performance hack - do not revert to g_slist_prepend()!
- */
- current_source_link.data = source;
- current_source_link.next = current->dispatching_sources;
- current->dispatching_sources = ¤t_source_link;
- need_destroy = ! dispatch (source,
- callback,
- user_data);
- g_assert (current->dispatching_sources == ¤t_source_link);
- current->dispatching_sources = current_source_link.next;
- current->depth--;
-
+ /* These operations are safe because 'current' is thread-local
+ * and not modified from anywhere but this function.
+ */
+ prev_source = current->source;
+ current->source = source;
+ current->depth++;
+
+ TRACE( GLIB_MAIN_BEFORE_DISPATCH (g_source_get_name (source)));
+ need_destroy = !(* dispatch) (source, callback, user_data);
+ TRACE( GLIB_MAIN_AFTER_DISPATCH (g_source_get_name (source)));
+
+ current->source = prev_source;
+ current->depth--;
+
if (cb_funcs)
cb_funcs->unref (cb_data);
if (!was_in_call)
source->flags &= ~G_HOOK_FLAG_IN_CALL;
- if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
- !SOURCE_DESTROYED (source))
+ if (SOURCE_BLOCKED (source) && !SOURCE_DESTROYED (source))
unblock_source (source);
/* Note: this depends on the fact that we can't switch
g_ptr_array_set_size (context->pending_dispatches, 0);
}
-/* Holds context's lock */
-static inline GSource *
-next_valid_source (GMainContext *context,
- GSource *source)
-{
- GSource *new_source = source ? source->next : context->source_list;
-
- while (new_source)
- {
- if (!SOURCE_DESTROYED (new_source))
- {
- new_source->ref_count++;
- break;
- }
-
- new_source = new_source->next;
- }
-
- if (source)
- SOURCE_UNREF (source, context);
-
- return new_source;
-}
-
/**
* g_main_context_acquire:
* @context: a #GMainContext
* can call g_main_context_prepare(), g_main_context_query(),
* g_main_context_check(), g_main_context_dispatch().
*
- * Return value: %TRUE if the operation succeeded, and
+ * Returns: %TRUE if the operation succeeded, and
* this thread is now the owner of @context.
**/
gboolean
* that owner releases ownership or until @cond is signaled, then
* try again (once) to become the owner.
*
- * Return value: %TRUE if the operation succeeded, and
+ * Returns: %TRUE if the operation succeeded, and
* this thread is now the owner of @context.
**/
gboolean
if (context == NULL)
context = g_main_context_default ();
+ if G_UNLIKELY (cond != &context->cond || mutex != &context->mutex)
+ {
+ static gboolean warned;
+
+ if (!warned)
+ {
+ g_critical ("WARNING!! g_main_context_wait() will be removed in a future release. "
+ "If you see this message, please file a bug immediately.");
+ warned = TRUE;
+ }
+ }
+
loop_internal_waiter = (mutex == &context->mutex);
if (!loop_internal_waiter)
* @context: a #GMainContext
* @priority: location to store priority of highest priority
* source already ready.
- *
+ *
* Prepares to poll sources within a main loop. The resulting information
* for polling is determined by calling g_main_context_query ().
- *
- * Return value: %TRUE if some source is ready to be dispatched
+ *
+ * You must have successfully acquired the context with
+ * g_main_context_acquire() before you may call this function.
+ *
+ * Returns: %TRUE if some source is ready to be dispatched
* prior to polling.
**/
gboolean
gint n_ready = 0;
gint current_priority = G_MAXINT;
GSource *source;
+ GSourceIter iter;
if (context == NULL)
context = g_main_context_default ();
context->timeout = -1;
- source = next_valid_source (context, NULL);
- while (source)
+ g_source_iter_init (&iter, context, TRUE);
+ while (g_source_iter_next (&iter, &source))
{
gint source_timeout = -1;
+ if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
+ continue;
if ((n_ready > 0) && (source->priority > current_priority))
- {
- SOURCE_UNREF (source, context);
- break;
- }
- if (SOURCE_BLOCKED (source))
- goto next;
+ break;
if (!(source->flags & G_SOURCE_READY))
{
gboolean result;
- gboolean (*prepare) (GSource *source,
- gint *timeout);
+ gboolean (* prepare) (GSource *source,
+ gint *timeout);
- prepare = source->source_funcs->prepare;
- context->in_check_or_prepare++;
- UNLOCK_CONTEXT (context);
+ prepare = source->source_funcs->prepare;
- result = (*prepare) (source, &source_timeout);
+ if (prepare)
+ {
+ context->in_check_or_prepare++;
+ UNLOCK_CONTEXT (context);
- LOCK_CONTEXT (context);
- context->in_check_or_prepare--;
+ result = (* prepare) (source, &source_timeout);
+
+ LOCK_CONTEXT (context);
+ context->in_check_or_prepare--;
+ }
+ else
+ {
+ source_timeout = -1;
+ result = FALSE;
+ }
+
+ if (result == FALSE && source->priv->ready_time != -1)
+ {
+ if (!context->time_is_fresh)
+ {
+ context->time = g_get_monotonic_time ();
+ context->time_is_fresh = TRUE;
+ }
+
+ if (source->priv->ready_time <= context->time)
+ {
+ source_timeout = 0;
+ result = TRUE;
+ }
+ else
+ {
+ gint timeout;
+
+ /* rounding down will lead to spinning, so always round up */
+ timeout = (source->priv->ready_time - context->time + 999) / 1000;
+
+ if (source_timeout < 0 || timeout < source_timeout)
+ source_timeout = timeout;
+ }
+ }
if (result)
{
while (ready_source)
{
ready_source->flags |= G_SOURCE_READY;
- ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
+ ready_source = ready_source->priv->parent_source;
}
}
}
else
context->timeout = MIN (context->timeout, source_timeout);
}
-
- next:
- source = next_valid_source (context, source);
}
+ g_source_iter_clear (&iter);
UNLOCK_CONTEXT (context);
* @fds: (out caller-allocates) (array length=n_fds): location to
* store #GPollFD records that need to be polled.
* @n_fds: length of @fds.
- *
+ *
* Determines information necessary to poll this main loop.
- *
- * Return value: the number of records actually stored in @fds,
+ *
+ * You must have successfully acquired the context with
+ * g_main_context_acquire() before you may call this function.
+ *
+ * Returns: the number of records actually stored in @fds,
* or, if more than @n_fds records need to be stored, the number
* of records that need to be stored.
**/
* @fds: (array length=n_fds): array of #GPollFD's that was passed to
* the last call to g_main_context_query()
* @n_fds: return value of g_main_context_query()
- *
+ *
* Passes the results of polling back to the main loop.
- *
- * Return value: %TRUE if some sources are ready to be dispatched.
+ *
+ * You must have successfully acquired the context with
+ * g_main_context_acquire() before you may call this function.
+ *
+ * Returns: %TRUE if some sources are ready to be dispatched.
**/
gboolean
g_main_context_check (GMainContext *context,
gint n_fds)
{
GSource *source;
+ GSourceIter iter;
GPollRec *pollrec;
gint n_ready = 0;
gint i;
return FALSE;
}
- if (context->wake_up_rec.events)
+ if (context->wake_up_rec.revents)
g_wakeup_acknowledge (context->wakeup);
/* If the set of poll file descriptors changed, bail out
i++;
}
- source = next_valid_source (context, NULL);
- while (source)
+ g_source_iter_init (&iter, context, TRUE);
+ while (g_source_iter_next (&iter, &source))
{
+ if (SOURCE_DESTROYED (source) || SOURCE_BLOCKED (source))
+ continue;
if ((n_ready > 0) && (source->priority > max_priority))
- {
- SOURCE_UNREF (source, context);
- break;
- }
- if (SOURCE_BLOCKED (source))
- goto next;
+ break;
if (!(source->flags & G_SOURCE_READY))
{
- gboolean result;
- gboolean (*check) (GSource *source);
+ gboolean result;
+ gboolean (* check) (GSource *source);
+
+ check = source->source_funcs->check;
+
+ if (check)
+ {
+ /* If the check function is set, call it. */
+ context->in_check_or_prepare++;
+ UNLOCK_CONTEXT (context);
+
+ result = (* check) (source);
+
+ LOCK_CONTEXT (context);
+ context->in_check_or_prepare--;
+ }
+ else
+ result = FALSE;
+
+ if (result == FALSE)
+ {
+ GSList *tmp_list;
+
+ /* If not already explicitly flagged ready by ->check()
+ * (or if we have no check) then we can still be ready if
+ * any of our fds poll as ready.
+ */
+ for (tmp_list = source->priv->fds; tmp_list; tmp_list = tmp_list->next)
+ {
+ GPollFD *pollfd = tmp_list->data;
+
+ if (pollfd->revents)
+ {
+ result = TRUE;
+ break;
+ }
+ }
+ }
+
+ if (result == FALSE && source->priv->ready_time != -1)
+ {
+ if (!context->time_is_fresh)
+ {
+ context->time = g_get_monotonic_time ();
+ context->time_is_fresh = TRUE;
+ }
+
+ if (source->priv->ready_time <= context->time)
+ result = TRUE;
+ }
- check = source->source_funcs->check;
-
- context->in_check_or_prepare++;
- UNLOCK_CONTEXT (context);
-
- result = (*check) (source);
-
- LOCK_CONTEXT (context);
- context->in_check_or_prepare--;
-
if (result)
{
GSource *ready_source = source;
while (ready_source)
{
ready_source->flags |= G_SOURCE_READY;
- ready_source = ready_source->priv ? ready_source->priv->parent_source : NULL;
+ ready_source = ready_source->priv->parent_source;
}
}
}
*/
max_priority = source->priority;
}
-
- next:
- source = next_valid_source (context, source);
}
+ g_source_iter_clear (&iter);
UNLOCK_CONTEXT (context);
/**
* g_main_context_dispatch:
* @context: a #GMainContext
- *
+ *
* Dispatches all pending sources.
+ *
+ * You must have successfully acquired the context with
+ * g_main_context_acquire() before you may call this function.
**/
void
g_main_context_dispatch (GMainContext *context)
if (!block)
timeout = 0;
- g_assert (!g_main_context_fork_detected);
g_main_context_poll (context, timeout, max_priority, fds, nfds);
some_ready = g_main_context_check (context, max_priority, fds, nfds);
/**
* g_main_context_pending:
- * @context: a #GMainContext (if %NULL, the default context will be used)
+ * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
*
* Checks if any sources have pending events for the given context.
*
- * Return value: %TRUE if events are pending.
+ * Returns: %TRUE if events are pending.
**/
gboolean
g_main_context_pending (GMainContext *context)
/**
* g_main_context_iteration:
- * @context: a #GMainContext (if %NULL, the default context will be used)
+ * @context: (allow-none): a #GMainContext (if %NULL, the default context will be used)
* @may_block: whether the call may block.
- *
+ *
* Runs a single iteration for the given main loop. This involves
* checking to see if any event sources are ready to be processed,
* then if no events sources are ready and @may_block is %TRUE, waiting
* for a source to become ready, then dispatching the highest priority
- * events sources that are ready. Otherwise, if @may_block is %FALSE
- * sources are not waited to become ready, only those highest priority
- * events sources will be dispatched (if any), that are ready at this
+ * events sources that are ready. Otherwise, if @may_block is %FALSE
+ * sources are not waited to become ready, only those highest priority
+ * events sources will be dispatched (if any), that are ready at this
* given moment without further waiting.
*
- * Note that even when @may_block is %TRUE, it is still possible for
- * g_main_context_iteration() to return %FALSE, since the the wait may
+ * Note that even when @may_block is %TRUE, it is still possible for
+ * g_main_context_iteration() to return %FALSE, since the wait may
* be interrupted for other reasons than an event source becoming ready.
- *
- * Return value: %TRUE if events were dispatched.
+ *
+ * Returns: %TRUE if events were dispatched.
**/
gboolean
g_main_context_iteration (GMainContext *context, gboolean may_block)
*
* Creates a new #GMainLoop structure.
*
- * Return value: a new #GMainLoop.
+ * Returns: a new #GMainLoop.
**/
GMainLoop *
g_main_loop_new (GMainContext *context,
*
* Increases the reference count on a #GMainLoop object by one.
*
- * Return value: @loop
+ * Returns: @loop
**/
GMainLoop *
g_main_loop_ref (GMainLoop *loop)
*
* Checks to see if the main loop is currently being run via g_main_loop_run().
*
- * Return value: %TRUE if the mainloop is currently being run.
+ * Returns: %TRUE if the mainloop is currently being run.
**/
gboolean
g_main_loop_is_running (GMainLoop *loop)
*
* Returns the #GMainContext of @loop.
*
- * Return value: (transfer none): the #GMainContext of @loop
+ * Returns: (transfer none): the #GMainContext of @loop
**/
GMainContext *
g_main_loop_get_context (GMainLoop *loop)
if (n_fds || timeout != 0)
{
#ifdef G_MAIN_POLL_DEBUG
+ poll_timer = NULL;
if (_g_main_poll_debug)
{
g_print ("polling context=%p n=%d timeout=%d\n",
/**
* g_main_context_add_poll:
- * @context: a #GMainContext (or %NULL for the default context)
+ * @context: (allow-none): a #GMainContext (or %NULL for the default context)
* @fd: a #GPollFD structure holding information about a file
* descriptor to watch.
* @priority: the priority for this file descriptor which should be
* the same as the priority used for g_source_attach() to ensure that the
* file descriptor is polled whenever the results may be needed.
- *
+ *
* Adds a file descriptor to the set of file descriptors polled for
* this context. This will very seldom be used directly. Instead
- * a typical event source will use g_source_add_poll() instead.
+ * a typical event source will use g_source_add_unix_fd() instead.
**/
void
g_main_context_add_poll (GMainContext *context,
*
* Gets the poll function set by g_main_context_set_poll_func().
*
- * Return value: the poll function
+ * Returns: the poll function
**/
GPollFunc
g_main_context_get_poll_func (GMainContext *context)
* g_main_context_wakeup:
* @context: a #GMainContext
*
- * If @context is currently waiting in a poll(), interrupt
- * the poll(), and continue the iteration process.
+ * If @context is currently blocking in g_main_context_iteration()
+ * waiting for a source to become ready, cause it to stop blocking
+ * and return. Otherwise, cause the next invocation of
+ * g_main_context_iteration() to return without blocking.
+ *
+ * This API is useful for low-level control over #GMainContext; for
+ * example, integrating it with main loop implementations such as
+ * #GMainLoop.
+ *
+ * Another related use for this function is when implementing a main
+ * loop with a termination condition, computed from multiple threads:
+ *
+ * |[<!-- language="C" -->
+ * #define NUM_TASKS 10
+ * static volatile gint tasks_remaining = NUM_TASKS;
+ * ...
+ *
+ * while (g_atomic_int_get (&tasks_remaining) != 0)
+ * g_main_context_iteration (NULL, TRUE);
+ * ]|
+ *
+ * Then in a thread:
+ * |[<!-- language="C" -->
+ * perform_work();
+ *
+ * if (g_atomic_int_dec_and_test (&tasks_remaining))
+ * g_main_context_wakeup (NULL);
+ * ]|
**/
void
g_main_context_wakeup (GMainContext *context)
g_timeout_set_expiration (GTimeoutSource *timeout_source,
gint64 current_time)
{
- timeout_source->expiration = current_time +
- (guint64) timeout_source->interval * 1000;
+ gint64 expiration;
+
+ expiration = current_time + (guint64) timeout_source->interval * 1000;
if (timeout_source->seconds)
{
* always only *increase* the expiration time by adding a full
* second in the case that the microsecond portion decreases.
*/
- timeout_source->expiration -= timer_perturb;
+ expiration -= timer_perturb;
- remainder = timeout_source->expiration % 1000000;
+ remainder = expiration % 1000000;
if (remainder >= 1000000/4)
- timeout_source->expiration += 1000000;
-
- timeout_source->expiration -= remainder;
- timeout_source->expiration += timer_perturb;
- }
-}
-
-static gboolean
-g_timeout_prepare (GSource *source,
- gint *timeout)
-{
- GTimeoutSource *timeout_source = (GTimeoutSource *) source;
- gint64 now = g_source_get_time (source);
+ expiration += 1000000;
- if (now < timeout_source->expiration)
- {
- /* Round up to ensure that we don't try again too early */
- *timeout = (timeout_source->expiration - now + 999) / 1000;
- return FALSE;
+ expiration -= remainder;
+ expiration += timer_perturb;
}
- *timeout = 0;
- return TRUE;
-}
-
-static gboolean
-g_timeout_check (GSource *source)
-{
- GTimeoutSource *timeout_source = (GTimeoutSource *) source;
- gint64 now = g_source_get_time (source);
-
- return timeout_source->expiration <= now;
+ g_source_set_ready_time ((GSource *) timeout_source, expiration);
}
static gboolean
* The interval given is in terms of monotonic time, not wall clock
* time. See g_get_monotonic_time().
*
- * Return value: the newly-created timeout source
+ * Returns: the newly-created timeout source
**/
GSource *
g_timeout_source_new (guint interval)
* The interval given in terms of monotonic time, not wall clock time.
* See g_get_monotonic_time().
*
- * Return value: the newly-created timeout source
+ * Returns: the newly-created timeout source
*
* Since: 2.14
**/
* (1/1000ths of a second)
* @function: function to call
* @data: data to pass to @function
- * @notify: function to call when the timeout is removed, or %NULL
+ * @notify: (allow-none): function to call when the timeout is removed, or %NULL
*
* Sets a function to be called at regular intervals, with the given
* priority. The function is called repeatedly until it returns
* The interval given in terms of monotonic time, not wall clock time.
* See g_get_monotonic_time().
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
* Rename to: g_timeout_add
**/
guint
* The interval given is in terms of monotonic time, not wall clock
* time. See g_get_monotonic_time().
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
**/
guint
g_timeout_add (guint32 interval,
* @interval: the time between calls to the function, in seconds
* @function: function to call
* @data: data to pass to @function
- * @notify: function to call when the timeout is removed, or %NULL
+ * @notify: (allow-none): function to call when the timeout is removed, or %NULL
*
* Sets a function to be called at regular intervals, with @priority.
* The function is called repeatedly until it returns %FALSE, at which
* The interval given is in terms of monotonic time, not wall clock
* time. See g_get_monotonic_time().
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
*
* Rename to: g_timeout_add_seconds
* Since: 2.14
* The interval given is in terms of monotonic time, not wall clock
* time. See g_get_monotonic_time().
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
*
* Since: 2.14
**/
}
static void
-dispatch_unix_signals (void)
+dispatch_unix_signals_unlocked (void)
{
+ gboolean pending[NSIG];
GSList *node;
+ gint i;
/* clear this first incase another one arrives while we're processing */
any_unix_signal_pending = FALSE;
- G_LOCK(unix_signal_lock);
+ /* We atomically test/clear the bit from the global array in case
+ * other signals arrive while we are dispatching.
+ *
+ * We then can safely use our own array below without worrying about
+ * races.
+ */
+ for (i = 0; i < NSIG; i++)
+ {
+ /* Be very careful with (the volatile) unix_signal_pending.
+ *
+ * We must ensure that it's not possible that we clear it without
+ * handling the signal. We therefore must ensure that our pending
+ * array has a field set (ie: we will do something about the
+ * signal) before we clear the item in unix_signal_pending.
+ *
+ * Note specifically: we must check _our_ array.
+ */
+ pending[i] = unix_signal_pending[i];
+ if (pending[i])
+ unix_signal_pending[i] = FALSE;
+ }
/* handle GChildWatchSource instances */
- if (unix_signal_pending[SIGCHLD])
+ if (pending[SIGCHLD])
{
- unix_signal_pending[SIGCHLD] = FALSE;
-
/* The only way we can do this is to scan all of the children.
*
* The docs promise that we will not reap children that we are not
if (!source->child_exited)
{
- if (waitpid (source->pid, &source->child_status, WNOHANG) > 0)
+ pid_t pid;
+ do
{
- source->child_exited = TRUE;
-
- wake_source ((GSource *) source);
+ g_assert (source->pid > 0);
+
+ pid = waitpid (source->pid, &source->child_status, WNOHANG);
+ if (pid > 0)
+ {
+ source->child_exited = TRUE;
+ wake_source ((GSource *) source);
+ }
+ else if (pid == -1 && errno == ECHILD)
+ {
+ g_warning ("GChildWatchSource: Exit status of a child process was requested but ECHILD was received by waitpid(). Most likely the process is ignoring SIGCHLD, or some other thread is invoking waitpid() with a nonpositive first argument; either behavior can break applications that use g_child_watch_add()/g_spawn_sync() either directly or indirectly.");
+ source->child_exited = TRUE;
+ source->child_status = 0;
+ wake_source ((GSource *) source);
+ }
}
+ while (pid == -1 && errno == EINTR);
}
}
}
if (!source->pending)
{
- if (unix_signal_pending[source->signum])
+ if (pending[source->signum])
{
- unix_signal_pending[source->signum] = FALSE;
source->pending = TRUE;
wake_source ((GSource *) source);
}
}
+}
+
+static void
+dispatch_unix_signals (void)
+{
+ G_LOCK(unix_signal_lock);
+ dispatch_unix_signals_unlocked ();
G_UNLOCK(unix_signal_lock);
}
gpointer user_data)
{
GUnixSignalWatchSource *unix_signal_source;
+ gboolean again;
unix_signal_source = (GUnixSignalWatchSource *) source;
return FALSE;
}
- (callback) (user_data);
+ again = (callback) (user_data);
unix_signal_source->pending = FALSE;
- return TRUE;
+ return again;
}
static void
-ensure_unix_signal_handler_installed_unlocked (int signum)
+ref_unix_signal_handler_unlocked (int signum)
{
- static sigset_t installed_signal_mask;
- static gboolean initialized;
- struct sigaction action;
-
- if (!initialized)
+ /* Ensure we have the worker context */
+ g_get_worker_context ();
+ unix_signal_refcount[signum]++;
+ if (unix_signal_refcount[signum] == 1)
{
- sigemptyset (&installed_signal_mask);
- g_get_worker_context ();
- initialized = TRUE;
+ struct sigaction action;
+ action.sa_handler = g_unix_signal_handler;
+ sigemptyset (&action.sa_mask);
+#ifdef SA_RESTART
+ action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
+#else
+ action.sa_flags = SA_NOCLDSTOP;
+#endif
+ sigaction (signum, &action, NULL);
}
+}
- if (sigismember (&installed_signal_mask, signum))
- return;
-
- sigaddset (&installed_signal_mask, signum);
-
- action.sa_handler = g_unix_signal_handler;
- sigemptyset (&action.sa_mask);
- action.sa_flags = SA_RESTART | SA_NOCLDSTOP;
- sigaction (signum, &action, NULL);
+static void
+unref_unix_signal_handler_unlocked (int signum)
+{
+ unix_signal_refcount[signum]--;
+ if (unix_signal_refcount[signum] == 0)
+ {
+ struct sigaction action;
+ memset (&action, 0, sizeof (action));
+ action.sa_handler = SIG_DFL;
+ sigemptyset (&action.sa_mask);
+ sigaction (signum, &action, NULL);
+ }
}
GSource *
unix_signal_source->pending = FALSE;
G_LOCK (unix_signal_lock);
- ensure_unix_signal_handler_installed_unlocked (signum);
+ ref_unix_signal_handler_unlocked (signum);
unix_signal_watches = g_slist_prepend (unix_signal_watches, unix_signal_source);
- if (unix_signal_pending[signum])
- unix_signal_source->pending = TRUE;
- unix_signal_pending[signum] = FALSE;
+ dispatch_unix_signals_unlocked ();
G_UNLOCK (unix_signal_lock);
return source;
static void
g_unix_signal_watch_finalize (GSource *source)
{
+ GUnixSignalWatchSource *unix_signal_source;
+
+ unix_signal_source = (GUnixSignalWatchSource *) source;
+
G_LOCK (unix_signal_lock);
+ unref_unix_signal_handler_unlocked (unix_signal_source->signum);
unix_signal_watches = g_slist_remove (unix_signal_watches, source);
G_UNLOCK (unix_signal_lock);
}
{
G_LOCK (unix_signal_lock);
unix_child_watches = g_slist_remove (unix_child_watches, source);
+ unref_unix_signal_handler_unlocked (SIGCHLD);
G_UNLOCK (unix_signal_lock);
}
/**
* g_child_watch_source_new:
- * @pid: process to watch. On POSIX the pid of a child process. On
+ * @pid: process to watch. On POSIX the positive pid of a child process. On
* Windows a handle for a process (which doesn't have to be a child).
*
* Creates a new child_watch source.
* executed.
*
* Note that child watch sources can only be used in conjunction with
- * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD
- * flag is used.
+ * `g_spawn...` when the %G_SPAWN_DO_NOT_REAP_CHILD flag is used.
*
* Note that on platforms where #GPid must be explicitly closed
* (see g_spawn_close_pid()) @pid must not be closed while the
* source is still active. Typically, you will want to call
* g_spawn_close_pid() in the callback function for the source.
*
- * Note further that using g_child_watch_source_new() is not
- * compatible with calling <literal>waitpid(-1)</literal> in
- * the application. Calling waitpid() for individual pids will
- * still work fine.
- *
- * Return value: the newly-created child watch source
+ * Note further that using g_child_watch_source_new() is not
+ * compatible with calling `waitpid` with a nonpositive first
+ * argument in the application. Calling waitpid() for individual
+ * pids will still work fine.
+ *
+ * Similarly, on POSIX platforms, the @pid passed to this function must
+ * be greater than 0 (i.e. this function must wait for a specific child,
+ * and cannot wait for one of many children by using a nonpositive argument).
+ *
+ * Returns: the newly-created child watch source
*
* Since: 2.4
**/
GSource *
g_child_watch_source_new (GPid pid)
{
- GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
- GChildWatchSource *child_watch_source = (GChildWatchSource *)source;
+ GSource *source;
+ GChildWatchSource *child_watch_source;
+
+#ifndef G_OS_WIN32
+ g_return_val_if_fail (pid > 0, NULL);
+#endif
+
+ source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource));
+ child_watch_source = (GChildWatchSource *)source;
child_watch_source->pid = pid;
g_source_add_poll (source, &child_watch_source->poll);
#else /* G_OS_WIN32 */
G_LOCK (unix_signal_lock);
- ensure_unix_signal_handler_installed_unlocked (SIGCHLD);
+ ref_unix_signal_handler_unlocked (SIGCHLD);
unix_child_watches = g_slist_prepend (unix_child_watches, child_watch_source);
if (waitpid (pid, &child_watch_source->child_status, WNOHANG) > 0)
child_watch_source->child_exited = TRUE;
* g_child_watch_add_full:
* @priority: the priority of the idle source. Typically this will be in the
* range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
- * @pid: process to watch. On POSIX the pid of a child process. On
+ * @pid: process to watch. On POSIX the positive pid of a child process. On
* Windows a handle for a process (which doesn't have to be a child).
* @function: function to call
* @data: data to pass to @function
- * @notify: function to call when the idle is removed, or %NULL
+ * @notify: (allow-none): function to call when the idle is removed, or %NULL
*
* Sets a function to be called when the child indicated by @pid
* exits, at the priority @priority.
* If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes()
* you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to
* the spawn function for the child watching to work.
+ *
+ * In many programs, you will want to call g_spawn_check_exit_status()
+ * in the callback to determine whether or not the child exited
+ * successfully.
*
- * Note that on platforms where #GPid must be explicitly closed
- * (see g_spawn_close_pid()) @pid must not be closed while the
- * source is still active. Typically, you will want to call
- * g_spawn_close_pid() in the callback function for the source.
+ * Also, note that on platforms where #GPid must be explicitly closed
+ * (see g_spawn_close_pid()) @pid must not be closed while the source
+ * is still active. Typically, you should invoke g_spawn_close_pid()
+ * in the callback function for the source.
*
* GLib supports only a single callback per process id.
*
* using g_source_attach(). You can do these steps manually if you
* need greater control.
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
*
* Rename to: g_child_watch_add
* Since: 2.4
guint id;
g_return_val_if_fail (function != NULL, 0);
+#ifndef G_OS_WIN32
+ g_return_val_if_fail (pid > 0, 0);
+#endif
source = g_child_watch_source_new (pid);
/**
* g_child_watch_add:
- * @pid: process id to watch. On POSIX the pid of a child process. On
- * Windows a handle for a process (which doesn't have to be a child).
+ * @pid: process id to watch. On POSIX the positive pid of a child
+ * process. On Windows a handle for a process (which doesn't have to be
+ * a child).
* @function: function to call
* @data: data to pass to @function
*
* using g_source_attach(). You can do these steps manually if you
* need greater control.
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
*
* Since: 2.4
**/
* %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which
* have a default priority of %G_PRIORITY_DEFAULT.
*
- * Return value: the newly-created idle source
+ * Returns: the newly-created idle source
**/
GSource *
g_idle_source_new (void)
* range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE.
* @function: function to call
* @data: data to pass to @function
- * @notify: function to call when the idle is removed, or %NULL
+ * @notify: (allow-none): function to call when the idle is removed, or %NULL
*
* Adds a function to be called whenever there are no higher priority
* events pending. If the function returns %FALSE it is automatically
* and attaches it to the main loop context using g_source_attach().
* You can do these steps manually if you need greater control.
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
* Rename to: g_idle_add
**/
guint
* and attaches it to the main loop context using g_source_attach().
* You can do these steps manually if you need greater control.
*
- * Return value: the ID (greater than 0) of the event source.
+ * Returns: the ID (greater than 0) of the event source.
**/
guint
g_idle_add (GSourceFunc function,
*
* Removes the idle function with the given data.
*
- * Return value: %TRUE if an idle source was found and removed.
+ * Returns: %TRUE if an idle source was found and removed.
**/
gboolean
g_idle_remove_by_data (gpointer data)
* @priority: the priority at which to run @function
* @function: function to call
* @data: data to pass to @function
- * @notify: a function to call when @data is no longer in use, or %NULL.
+ * @notify: (allow-none): a function to call when @data is no longer in use, or %NULL.
*
* Invokes a function in such a way that @context is owned during the
* invocation of @function.
if (g_once_init_enter (&initialised))
{
- GError *error = NULL;
+ /* mask all signals in the worker thread */
+#ifdef G_OS_UNIX
+ sigset_t prev_mask;
+ sigset_t all;
+ sigfillset (&all);
+ pthread_sigmask (SIG_SETMASK, &all, &prev_mask);
+#endif
glib_worker_context = g_main_context_new ();
- if (g_thread_new ("gmain", glib_worker_main, NULL, &error) == NULL)
- g_error ("Creating GLib worker thread failed: %s\n", error->message);
-
+ g_thread_new ("gmain", glib_worker_main, NULL);
+#ifdef G_OS_UNIX
+ pthread_sigmask (SIG_SETMASK, &prev_mask, NULL);
+#endif
g_once_init_leave (&initialised, TRUE);
}