X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=glib%2Fgmain.c;h=d6037ba4cb91733fa0a594efb7efae4117f673d5;hb=93349e6ea36fa5dd48ee2fa2cd9b8328414cf3c5;hp=75c2c0e3d042fcb50d983b71c0b665cc18ac9b5e;hpb=1b28408b8bfe282f671716a39bba3208d3fef39a;p=platform%2Fupstream%2Fglib.git diff --git a/glib/gmain.c b/glib/gmain.c index 75c2c0e..d6037ba 100644 --- a/glib/gmain.c +++ b/glib/gmain.c @@ -49,6 +49,7 @@ #ifdef G_OS_UNIX #include "glib-unix.h" +#include #ifdef HAVE_EVENTFD #include #endif @@ -86,7 +87,6 @@ #include "gqueue.h" #include "gstrfuncs.h" #include "gtestutils.h" -#include "gthreadprivate.h" #ifdef G_OS_WIN32 #include "gwin32.h" @@ -97,6 +97,9 @@ #endif #include "gwakeup.h" +#include "gmain-internal.h" +#include "glib-init.h" +#include "glib-private.h" /** * SECTION:main @@ -172,6 +175,10 @@ * * * + * + * 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. */ /* Types */ @@ -185,10 +192,18 @@ typedef struct _GSourceCallback GSourceCallback; 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; -#ifdef G_THREADS_ENABLED +typedef struct _GSourceList GSourceList; + +struct _GSourceList +{ + GSource *head, *tail; + gint priority; +}; + typedef struct _GMainWaiter GMainWaiter; struct _GMainWaiter @@ -196,7 +211,6 @@ struct _GMainWaiter GCond *cond; GMutex *mutex; }; -#endif typedef struct _GMainDispatch GMainDispatch; @@ -212,16 +226,14 @@ gboolean _g_main_poll_debug = FALSE; struct _GMainContext { -#ifdef G_THREADS_ENABLED /* The following lock is used for both the list of sources * and the list of poll records */ - GStaticMutex mutex; - GCond *cond; + GMutex mutex; + GCond cond; GThread *owner; guint owner_count; GSList *waiters; -#endif gint ref_count; @@ -229,7 +241,8 @@ struct _GMainContext gint timeout; /* Timeout for current iteration */ guint next_id; - GSource *source_list; + GHashTable *overflow_used_source_ids; /* set */ + GList *source_lists; gint in_check_or_prepare; GPollRec *poll_records, *poll_records_tail; @@ -237,22 +250,17 @@ struct _GMainContext GPollFD *cached_poll_array; guint cached_poll_array_size; -#ifdef G_THREADS_ENABLED GWakeup *wakeup; GPollFD wake_up_rec; - gboolean poll_waiting; /* Flag indicating whether the set of fd's changed during a poll */ gboolean poll_changed; -#endif /* G_THREADS_ENABLED */ GPollFunc poll_func; gint64 time; gboolean time_is_fresh; - gint64 real_time; - gboolean real_time_is_fresh; }; struct _GSourceCallback @@ -273,7 +281,6 @@ struct _GMainLoop struct _GTimeoutSource { GSource source; - gint64 expiration; guint interval; gboolean seconds; }; @@ -286,7 +293,6 @@ struct _GChildWatchSource #ifdef G_OS_WIN32 GPollFD poll; #else /* G_OS_WIN32 */ - gint count; gboolean child_exited; #endif /* G_OS_WIN32 */ }; @@ -310,21 +316,29 @@ struct _GSourcePrivate { 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; }; -#ifdef G_THREADS_ENABLED -#define LOCK_CONTEXT(context) g_static_mutex_lock (&context->mutex) -#define UNLOCK_CONTEXT(context) g_static_mutex_unlock (&context->mutex) +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 () -#else -#define LOCK_CONTEXT(context) (void)0 -#define UNLOCK_CONTEXT(context) (void)0 -#define G_THREAD_SELF NULL -#endif #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 { \ @@ -346,6 +360,9 @@ static void g_source_destroy_internal (GSource *source, 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, @@ -356,13 +373,14 @@ static void g_main_context_add_poll_unlocked (GMainContext *context, GPollFD *fd); static void g_main_context_remove_poll_unlocked (GMainContext *context, GPollFD *fd); -static void g_main_context_wakeup_unlocked (GMainContext *context); -static void _g_main_wake_up_all_contexts (void); +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_prepare (GSource *source, - gint *timeout); -static gboolean g_timeout_check (GSource *source); static gboolean g_timeout_dispatch (GSource *source, GSourceFunc callback, gpointer user_data); @@ -372,8 +390,8 @@ static gboolean g_child_watch_check (GSource *source); static gboolean g_child_watch_dispatch (GSource *source, GSourceFunc callback, gpointer user_data); +static void g_child_watch_finalize (GSource *source); #ifdef G_OS_UNIX -static gpointer unix_signal_helper_thread (gpointer data) G_GNUC_NORETURN; static void g_unix_signal_handler (int signum); static gboolean g_unix_signal_watch_prepare (GSource *source, gint *timeout); @@ -390,40 +408,31 @@ static gboolean g_idle_dispatch (GSource *source, GSourceFunc callback, gpointer user_data); +static void block_source (GSource *source); + +static GMainContext *glib_worker_context; + G_LOCK_DEFINE_STATIC (main_loop); static GMainContext *default_main_context; -static GSList *main_contexts_without_pipe = NULL; #ifndef G_OS_WIN32 -/* The UNIX signal pipe contains a single byte specifying which - * signal was received. - */ -#define _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR 'C' -#define _UNIX_SIGNAL_PIPE_SIGHUP_CHAR 'H' -#define _UNIX_SIGNAL_PIPE_SIGINT_CHAR 'I' -#define _UNIX_SIGNAL_PIPE_SIGTERM_CHAR 'T' -/* Guards all the data below */ + +/* UNIX signals work by marking one of these variables then waking the + * worker context to check on them and dispatch accordingly. + */ +#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 + +/* Guards all the data below */ G_LOCK_DEFINE_STATIC (unix_signal_lock); -enum { - UNIX_SIGNAL_UNINITIALIZED = 0, - UNIX_SIGNAL_INITIALIZED_SINGLE, - UNIX_SIGNAL_INITIALIZED_THREADED -}; -static gint unix_signal_init_state = UNIX_SIGNAL_UNINITIALIZED; -typedef struct { - /* These are only used in the UNIX_SIGNAL_INITIALIZED_SINGLE case */ - gboolean sighup_delivered : 1; - gboolean sigint_delivered : 1; - gboolean sigterm_delivered : 1; -} UnixSignalState; -static sigset_t unix_signal_mask; -static UnixSignalState unix_signal_state; -static gint unix_signal_wake_up_pipe[2]; -GSList *unix_signal_watches; - -/* Not guarded ( FIXME should it be? ) */ -static gint child_watch_count = 1; +static GSList *unix_signal_watches; +static GSList *unix_child_watches; static GSourceFuncs g_unix_signal_funcs = { @@ -438,8 +447,8 @@ static GSList *main_context_list = NULL; GSourceFuncs g_timeout_funcs = { - g_timeout_prepare, - g_timeout_check, + NULL, /* prepare */ + NULL, /* check */ g_timeout_dispatch, NULL }; @@ -449,7 +458,7 @@ GSourceFuncs g_child_watch_funcs = g_child_watch_prepare, g_child_watch_check, g_child_watch_dispatch, - NULL + g_child_watch_finalize }; GSourceFuncs g_idle_funcs = @@ -496,7 +505,11 @@ poll_rec_list_free (GMainContext *context, void g_main_context_unref (GMainContext *context) { + GSourceIter iter; GSource *source; + GList *sl_iter; + GSourceList *list; + g_return_if_fail (context != NULL); g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); @@ -507,62 +520,50 @@ g_main_context_unref (GMainContext *context) main_context_list = g_slist_remove (main_context_list, context); G_UNLOCK (main_context_list); - source = context->source_list; - while (source) + /* 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)) { - GSource *next = source->next; - g_source_destroy_internal (source, context, FALSE); - source = next; + source->context = NULL; + g_source_destroy_internal (source, context, TRUE); } + UNLOCK_CONTEXT (context); -#ifdef G_THREADS_ENABLED - g_static_mutex_free (&context->mutex); -#endif + for (sl_iter = context->source_lists; sl_iter; sl_iter = sl_iter->next) + { + list = sl_iter->data; + g_slice_free (GSourceList, list); + } + g_list_free (context->source_lists); + + if (context->overflow_used_source_ids) + g_hash_table_destroy (context->overflow_used_source_ids); + + g_mutex_clear (&context->mutex); g_ptr_array_free (context->pending_dispatches, TRUE); g_free (context->cached_poll_array); poll_rec_list_free (context, context->poll_records); - -#ifdef G_THREADS_ENABLED - if (g_thread_supported()) - g_wakeup_free (context->wakeup); - - else - main_contexts_without_pipe = g_slist_remove (main_contexts_without_pipe, - context); - if (context->cond != NULL) - g_cond_free (context->cond); -#endif + g_wakeup_free (context->wakeup); + g_cond_clear (&context->cond); g_free (context); } -#ifdef G_THREADS_ENABLED -static void -g_main_context_init_pipe (GMainContext *context) -{ - context->wakeup = g_wakeup_new (); - g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec); - g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec); -} - -void -_g_main_thread_init (void) +/* Helper function used by mainloop/overflow test. + */ +GMainContext * +g_main_context_new_with_next_id (guint next_id) { - GSList *curr; + GMainContext *ret = g_main_context_new (); - curr = main_contexts_without_pipe; - while (curr) - { - g_main_context_init_pipe ((GMainContext *)curr->data); - curr = curr->next; - } - g_slist_free (main_contexts_without_pipe); - main_contexts_without_pipe = NULL; + ret->next_id = next_id; + + return ret; } -#endif /* G_THREADS_ENABLED */ /** * g_main_context_new: @@ -574,33 +575,32 @@ _g_main_thread_init (void) GMainContext * g_main_context_new (void) { - GMainContext *context = g_new0 (GMainContext, 1); + static gsize initialised; + GMainContext *context; + if (g_once_init_enter (&initialised)) + { #ifdef G_MAIN_POLL_DEBUG - { - static gboolean beenhere = FALSE; - - if (!beenhere) - { - if (getenv ("G_MAIN_POLL_DEBUG") != NULL) - _g_main_poll_debug = TRUE; - beenhere = TRUE; - } - } + if (getenv ("G_MAIN_POLL_DEBUG") != NULL) + _g_main_poll_debug = TRUE; #endif -#ifdef G_THREADS_ENABLED - g_static_mutex_init (&context->mutex); + g_once_init_leave (&initialised, TRUE); + } + + context = g_new0 (GMainContext, 1); + + g_mutex_init (&context->mutex); + g_cond_init (&context->cond); context->owner = NULL; context->waiters = NULL; -#endif context->ref_count = 1; context->next_id = 1; - context->source_list = NULL; + context->source_lists = NULL; context->poll_func = g_poll; @@ -610,15 +610,10 @@ g_main_context_new (void) context->pending_dispatches = g_ptr_array_new (); context->time_is_fresh = FALSE; - context->real_time_is_fresh = FALSE; -#ifdef G_THREADS_ENABLED - if (g_thread_supported ()) - g_main_context_init_pipe (context); - else - main_contexts_without_pipe = g_slist_prepend (main_contexts_without_pipe, - context); -#endif + context->wakeup = g_wakeup_new (); + g_wakeup_get_pollfd (context->wakeup, &context->wake_up_rec); + g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec); G_LOCK (main_context_list); main_context_list = g_slist_append (main_context_list, context); @@ -641,7 +636,7 @@ g_main_context_new (void) * specified, and corresponds to the "main" main loop. See also * g_main_context_get_thread_default(). * - * Return value: the global default main context. + * Return value: (transfer none): the global default main context. **/ GMainContext * g_main_context_default (void) @@ -664,27 +659,27 @@ g_main_context_default (void) return default_main_context; } -static GStaticPrivate thread_context_stack = G_STATIC_PRIVATE_INIT; +static void +free_context (gpointer data) +{ + GMainContext *context = data; + + g_main_context_release (context); + if (context) + g_main_context_unref (context); +} static void free_context_stack (gpointer data) { - GQueue *stack = data; - GMainContext *context; - - 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_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 @@ -731,12 +726,11 @@ g_main_context_push_thread_default (GMainContext *context) else if (context) g_main_context_ref (context); - stack = g_static_private_get (&thread_context_stack); + stack = g_private_get (&thread_context_stack); if (!stack) { stack = g_queue_new (); - g_static_private_set (&thread_context_stack, stack, - free_context_stack); + g_private_set (&thread_context_stack, stack); } g_queue_push_head (stack, context); @@ -744,7 +738,7 @@ g_main_context_push_thread_default (GMainContext *context) /** * 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). @@ -759,7 +753,7 @@ g_main_context_pop_thread_default (GMainContext *context) if (context == g_main_context_default ()) context = NULL; - stack = g_static_private_get (&thread_context_stack); + stack = g_private_get (&thread_context_stack); g_return_if_fail (stack != NULL); g_return_if_fail (g_queue_peek_head (stack) == context); @@ -776,14 +770,18 @@ g_main_context_pop_thread_default (GMainContext *context) * * Gets the thread-default #GMainContext for this thread. Asynchronous * operations that want to be able to be run in contexts other than - * the default one should call this method to get a #GMainContext to - * add their #GSources to. (Note that even in single-threaded + * the default one should call this method or + * g_main_context_ref_thread_default() to get a #GMainContext to add + * 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 threads are not initialized.) + * always return %NULL if you are running in the default thread.) * - * Returns: the thread-default #GMainContext, or %NULL if the - * thread-default context is the global default context. + * If you need to hold a reference on the context, use + * g_main_context_ref_thread_default() instead. + * + * Returns: (transfer none): the thread-default #GMainContext, or + * %NULL if the thread-default context is the global default context. * * Since: 2.22 **/ @@ -792,13 +790,39 @@ g_main_context_get_thread_default (void) { GQueue *stack; - stack = g_static_private_get (&thread_context_stack); + stack = g_private_get (&thread_context_stack); if (stack) return g_queue_peek_head (stack); else return NULL; } +/** + * g_main_context_ref_thread_default: + * + * Gets the thread-default #GMainContext for this thread, as with + * g_main_context_get_thread_default(), but also adds a reference to + * it with g_main_context_ref(). In addition, unlike + * g_main_context_get_thread_default(), if the thread-default context + * is the global default context, this will return that #GMainContext + * (with a ref added to it) rather than returning %NULL. + * + * Returns: (transfer full): the thread-default #GMainContext. Unref + * with g_main_context_unref() when you are done with it. + * + * Since: 2.32 + */ +GMainContext * +g_main_context_ref_thread_default (void) +{ + GMainContext *context; + + context = g_main_context_get_thread_default (); + if (!context) + context = g_main_context_default (); + return g_main_context_ref (context); +} + /* Hooks for adding to the main loop */ /** @@ -828,7 +852,7 @@ 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; @@ -836,77 +860,263 @@ g_source_new (GSourceFuncs *source_funcs, 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); + } + + if (context->overflow_used_source_ids) + g_hash_table_remove (context->overflow_used_source_ids, + GUINT_TO_POINTER (source->source_id)); + +} + +static void +assign_source_id_unlocked (GMainContext *context, + GSource *source) +{ + guint id; + + /* Are we about to overflow back to 0? + * See https://bugzilla.gnome.org/show_bug.cgi?id=687098 + */ + if (G_UNLIKELY (context->next_id == G_MAXUINT && + context->overflow_used_source_ids == NULL)) + { + GSourceIter iter; + GSource *source; + + context->overflow_used_source_ids = g_hash_table_new (NULL, NULL); + + g_source_iter_init (&iter, context, FALSE); + while (g_source_iter_next (&iter, &source)) + { + g_hash_table_add (context->overflow_used_source_ids, + GUINT_TO_POINTER (source->source_id)); + } + id = G_MAXUINT; + } + else if (context->overflow_used_source_ids == NULL) + { + id = context->next_id++; + } + else + { + /* + * If we overran G_MAXUINT, we fall back to randomly probing the + * source ids for the current context. This will be slower the more + * sources there are, but we're mainly concerned right now about + * correctness and code size. There's time for a more clever solution + * later. + */ + do + id = g_random_int (); + while (id == 0 || + g_hash_table_contains (context->overflow_used_source_ids, + GUINT_TO_POINTER (id))); + g_hash_table_add (context->overflow_used_source_ids, GUINT_TO_POINTER (id)); + } + + source->source_id = id; } static guint g_source_attach_unlocked (GSource *source, GMainContext *context) { - guint result = 0; GSList *tmp_list; source->context = context; - result = source->source_id = context->next_id++; - + assign_source_id_unlocked (context, source); source->ref_count++; - g_source_list_add (source, context); + source_add_to_context (source, context); tmp_list = source->poll_fds; while (tmp_list) @@ -915,23 +1125,23 @@ g_source_attach_unlocked (GSource *source, tmp_list = tmp_list->next; } - if (source->priv) + 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); + + 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); + tmp_list = tmp_list->next; } - return result; + 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(). @@ -955,10 +1165,11 @@ g_source_attach (GSource *source, result = g_source_attach_unlocked (source, context); -#ifdef G_THREADS_ENABLED - /* Now wake up the main loop if it is waiting in the poll() */ - g_main_context_wakeup_unlocked (context); -#endif + /* 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); UNLOCK_CONTEXT (context); @@ -1002,25 +1213,16 @@ g_source_destroy_internal (GSource *source, 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); } @@ -1083,16 +1285,22 @@ 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: the #GMainContext with which the source is associated, - * or %NULL if the context has not yet been added - * to a source. + * Return value: (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; } @@ -1102,12 +1310,16 @@ g_source_get_context (GSource *source) * @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. + * + * 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, @@ -1200,22 +1412,19 @@ g_source_add_child_source (GSource *source, 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) { @@ -1224,6 +1433,20 @@ g_source_add_child_source (GSource *source, } } +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 @@ -1242,7 +1465,7 @@ g_source_remove_child_source (GSource *source, 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)); @@ -1251,9 +1474,7 @@ g_source_remove_child_source (GSource *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); @@ -1349,7 +1570,7 @@ static GSourceCallbackFuncs g_source_callback_funcs = { * @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. @@ -1411,15 +1632,22 @@ g_source_set_priority_unlocked (GSource *source, { 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)) { @@ -1431,10 +1659,16 @@ g_source_set_priority_unlocked (GSource *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) @@ -1489,6 +1723,79 @@ 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. + * + * 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 @@ -1675,7 +1982,7 @@ g_source_unref_internal (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); } if (source->source_funcs->finalize) @@ -1693,11 +2000,10 @@ g_source_unref_internal (GSource *source, 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); } @@ -1735,17 +2041,18 @@ g_source_unref (GSource *source) /** * g_main_context_find_source_by_id: - * @context: a #GMainContext (if %NULL, the default context will be used) + * @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: the #GSource if found, otherwise, %NULL + * Return value: (transfer none): the #GSource if found, otherwise, %NULL **/ GSource * g_main_context_find_source_by_id (GMainContext *context, guint source_id) { + GSourceIter iter; GSource *source; g_return_val_if_fail (source_id > 0, NULL); @@ -1755,14 +2062,14 @@ g_main_context_find_source_by_id (GMainContext *context, 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_id == source_id) break; - source = source->next; } + g_source_iter_clear (&iter); UNLOCK_CONTEXT (context); @@ -1771,7 +2078,7 @@ g_main_context_find_source_by_id (GMainContext *context, /** * 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. * @@ -1779,13 +2086,14 @@ g_main_context_find_source_by_id (GMainContext *context, * multiple sources exist with the same source function and user data, * the first one found will be returned. * - * Return value: the source, if one was found, otherwise %NULL + * Return value: (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); @@ -1795,8 +2103,8 @@ g_main_context_find_source_by_funcs_user_data (GMainContext *context, 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 && @@ -1810,8 +2118,8 @@ g_main_context_find_source_by_funcs_user_data (GMainContext *context, if (callback_data == user_data) break; } - source = source->next; } + g_source_iter_clear (&iter); UNLOCK_CONTEXT (context); @@ -1827,12 +2135,13 @@ g_main_context_find_source_by_funcs_user_data (GMainContext *context, * multiple sources exist with the same user data, the first * one found will be returned. * - * Return value: the source, if one was found, otherwise %NULL + * Return value: (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) @@ -1840,8 +2149,8 @@ g_main_context_find_source_by_user_data (GMainContext *context, 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) @@ -1854,8 +2163,8 @@ g_main_context_find_source_by_user_data (GMainContext *context, if (callback_data == user_data) break; } - source = source->next; } + g_source_iter_clear (&iter); UNLOCK_CONTEXT (context); @@ -1946,6 +2255,174 @@ 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. + * + * 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(). + * + * 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. + * + * 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. + * + * 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. @@ -2014,23 +2491,42 @@ g_get_real_time (void) return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec; } +#ifdef 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; +} +#endif + /** * g_get_monotonic_time: * * Queries the system monotonic time, if available. * - * On POSIX systems with clock_gettime() and %CLOCK_MONOTONIC this call + * 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). * - * It's important to note that POSIX %CLOCK_MONOTONIC does not count - * time spent while the machine is suspended. + * It's important to note that POSIX CLOCK_MONOTONIC does + * not count time spent while 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). + * is approximately every 16ms). Also, on XP (but not on Vista or later) + * the monotonic clock is locally monotonic, but may differ in exact + * value between processes due to timer wrap handling. * * Returns: the monotonic time, in microseconds * @@ -2041,67 +2537,154 @@ g_get_monotonic_time (void) { #ifdef HAVE_CLOCK_GETTIME /* librt clock_gettime() is our first choice */ - { - static int clockid = CLOCK_REALTIME; - struct timespec ts; - -#ifdef HAVE_MONOTONIC_CLOCK - /* We have to check if we actually have monotonic clock support. - * - * There is no thread safety issue here since there is no harm if we - * check twice. - */ - { - static gboolean checked; + struct timespec ts; - if G_UNLIKELY (!checked) - { - if (sysconf (_SC_MONOTONIC_CLOCK) >= 0) - clockid = CLOCK_MONOTONIC; - checked = TRUE; - } - } +#ifdef CLOCK_MONOTONIC + clock_gettime (CLOCK_MONOTONIC, &ts); +#else + clock_gettime (CLOCK_REALTIME, &ts); #endif - clock_gettime (clockid, &ts); - - /* 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)); - - return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000); - } -#else - /* 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. + /* 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)); + + return (((gint64) ts.tv_sec) * 1000000) + (ts.tv_nsec / 1000); + +#elif defined (G_OS_WIN32) + 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 */ - { - GTimeVal tv; - g_get_current_time (&tv); + 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; + +#else /* !HAVE_CLOCK_GETTIME && ! G_OS_WIN32*/ + + GTimeVal tv; - return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec; - } + g_get_current_time (&tv); + + return (((gint64) tv.tv_sec) * 1000000) + tv.tv_usec; #endif } @@ -2116,12 +2699,15 @@ g_main_dispatch_free (gpointer dispatch) static GMainDispatch * get_dispatch (void) { - static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT; - GMainDispatch *dispatch = g_static_private_get (&depth_private); + static GPrivate depth_private = G_PRIVATE_INIT (g_main_dispatch_free); + GMainDispatch *dispatch; + + dispatch = g_private_get (&depth_private); + if (!dispatch) { dispatch = g_slice_new0 (GMainDispatch); - g_static_private_set (&depth_private, dispatch, g_main_dispatch_free); + g_private_set (&depth_private, dispatch); } return dispatch; @@ -2255,7 +2841,7 @@ g_main_depth (void) * * Returns the currently firing source for this thread. * - * Return value: The currently firing source or %NULL. + * Return value: (transfer none): The currently firing source or %NULL. * * Since: 2.12 */ @@ -2287,7 +2873,7 @@ g_main_current_source (void) * self->idle_id = 0; * GDK_THREADS_LEAVE (); * - * return FALSE; + * return G_SOURCE_REMOVE; * } * * static void @@ -2353,12 +2939,27 @@ block_source (GSource *source) g_return_if_fail (!SOURCE_BLOCKED (source)); + source->flags |= G_SOURCE_BLOCKED; + 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; + } + } } /* HOLDS: source->context's lock */ @@ -2366,16 +2967,31 @@ static void 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 */ @@ -2454,8 +3070,7 @@ g_main_dispatch (GMainContext *context) 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 @@ -2474,30 +3089,6 @@ g_main_dispatch (GMainContext *context) 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 @@ -2519,7 +3110,6 @@ next_valid_source (GMainContext *context, gboolean g_main_context_acquire (GMainContext *context) { -#ifdef G_THREADS_ENABLED gboolean result = FALSE; GThread *self = G_THREAD_SELF; @@ -2543,9 +3133,6 @@ g_main_context_acquire (GMainContext *context) UNLOCK_CONTEXT (context); return result; -#else /* !G_THREADS_ENABLED */ - return TRUE; -#endif /* G_THREADS_ENABLED */ } /** @@ -2560,7 +3147,6 @@ g_main_context_acquire (GMainContext *context) void g_main_context_release (GMainContext *context) { -#ifdef G_THREADS_ENABLED if (context == NULL) context = g_main_context_default (); @@ -2574,8 +3160,7 @@ g_main_context_release (GMainContext *context) if (context->waiters) { GMainWaiter *waiter = context->waiters->data; - gboolean loop_internal_waiter = - (waiter->mutex == g_static_mutex_get_mutex (&context->mutex)); + gboolean loop_internal_waiter = (waiter->mutex == &context->mutex); context->waiters = g_slist_delete_link (context->waiters, context->waiters); if (!loop_internal_waiter) @@ -2589,7 +3174,6 @@ g_main_context_release (GMainContext *context) } UNLOCK_CONTEXT (context); -#endif /* G_THREADS_ENABLED */ } /** @@ -2612,7 +3196,6 @@ g_main_context_wait (GMainContext *context, GCond *cond, GMutex *mutex) { -#ifdef G_THREADS_ENABLED gboolean result = FALSE; GThread *self = G_THREAD_SELF; gboolean loop_internal_waiter; @@ -2620,7 +3203,7 @@ g_main_context_wait (GMainContext *context, if (context == NULL) context = g_main_context_default (); - loop_internal_waiter = (mutex == g_static_mutex_get_mutex (&context->mutex)); + loop_internal_waiter = (mutex == &context->mutex); if (!loop_internal_waiter) LOCK_CONTEXT (context); @@ -2659,9 +3242,6 @@ g_main_context_wait (GMainContext *context, UNLOCK_CONTEXT (context); return result; -#else /* !G_THREADS_ENABLED */ - return TRUE; -#endif /* G_THREADS_ENABLED */ } /** @@ -2684,6 +3264,7 @@ g_main_context_prepare (GMainContext *context, gint n_ready = 0; gint current_priority = G_MAXINT; GSource *source; + GSourceIter iter; if (context == NULL) context = g_main_context_default (); @@ -2691,7 +3272,6 @@ g_main_context_prepare (GMainContext *context, LOCK_CONTEXT (context); context->time_is_fresh = FALSE; - context->real_time_is_fresh = FALSE; if (context->in_check_or_prepare) { @@ -2701,17 +3281,6 @@ g_main_context_prepare (GMainContext *context, return FALSE; } -#ifdef G_THREADS_ENABLED - if (context->poll_waiting) - { - g_warning("g_main_context_prepare(): main loop already active in another thread"); - UNLOCK_CONTEXT (context); - return FALSE; - } - - context->poll_waiting = TRUE; -#endif /* G_THREADS_ENABLED */ - #if 0 /* If recursing, finish up current dispatch, before starting over */ if (context->pending_dispatches) @@ -2737,33 +3306,64 @@ g_main_context_prepare (GMainContext *context, 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) { @@ -2772,7 +3372,7 @@ g_main_context_prepare (GMainContext *context, 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; } } } @@ -2791,10 +3391,8 @@ g_main_context_prepare (GMainContext *context, else context->timeout = MIN (context->timeout, source_timeout); } - - next: - source = next_valid_source (context, source); } + g_source_iter_clear (&iter); UNLOCK_CONTEXT (context); @@ -2808,8 +3406,9 @@ g_main_context_prepare (GMainContext *context, * g_main_context_query: * @context: a #GMainContext * @max_priority: maximum priority source to check - * @timeout_: location to store timeout to be used in polling - * @fds: location to store #GPollFD records that need to be polled. + * @timeout_: (out): location to store timeout to be used in polling + * @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. @@ -2855,18 +3454,13 @@ g_main_context_query (GMainContext *context, n_poll++; } -#ifdef G_THREADS_ENABLED context->poll_changed = FALSE; -#endif if (timeout) { *timeout = context->timeout; if (*timeout != 0) - { - context->time_is_fresh = FALSE; - context->real_time_is_fresh = FALSE; - } + context->time_is_fresh = FALSE; } UNLOCK_CONTEXT (context); @@ -2878,8 +3472,8 @@ g_main_context_query (GMainContext *context, * g_main_context_check: * @context: a #GMainContext * @max_priority: the maximum numerical priority of sources to check - * @fds: array of #GPollFD's that was passed to the last call to - * g_main_context_query() + * @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. @@ -2893,6 +3487,7 @@ g_main_context_check (GMainContext *context, gint n_fds) { GSource *source; + GSourceIter iter; GPollRec *pollrec; gint n_ready = 0; gint i; @@ -2906,13 +3501,9 @@ g_main_context_check (GMainContext *context, UNLOCK_CONTEXT (context); return FALSE; } - -#ifdef G_THREADS_ENABLED - if (!context->poll_waiting) - g_wakeup_acknowledge (context->wakeup); - else - context->poll_waiting = FALSE; + if (context->wake_up_rec.revents) + g_wakeup_acknowledge (context->wakeup); /* If the set of poll file descriptors changed, bail out * and let the main loop rerun @@ -2922,7 +3513,6 @@ g_main_context_check (GMainContext *context, UNLOCK_CONTEXT (context); return FALSE; } -#endif /* G_THREADS_ENABLED */ pollrec = context->poll_records; i = 0; @@ -2935,32 +3525,67 @@ g_main_context_check (GMainContext *context, 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; @@ -2968,7 +3593,7 @@ g_main_context_check (GMainContext *context, 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; } } } @@ -2985,10 +3610,8 @@ g_main_context_check (GMainContext *context, */ max_priority = source->priority; } - - next: - source = next_valid_source (context, source); } + g_source_iter_clear (&iter); UNLOCK_CONTEXT (context); @@ -3029,31 +3652,24 @@ g_main_context_iterate (GMainContext *context, UNLOCK_CONTEXT (context); -#ifdef G_THREADS_ENABLED if (!g_main_context_acquire (context)) { gboolean got_ownership; LOCK_CONTEXT (context); - g_return_val_if_fail (g_thread_supported (), FALSE); - if (!block) return FALSE; - if (!context->cond) - context->cond = g_cond_new (); - got_ownership = g_main_context_wait (context, - context->cond, - g_static_mutex_get_mutex (&context->mutex)); + &context->cond, + &context->mutex); if (!got_ownership) return FALSE; } else LOCK_CONTEXT (context); -#endif /* G_THREADS_ENABLED */ if (!context->cached_poll_array) { @@ -3088,9 +3704,7 @@ g_main_context_iterate (GMainContext *context, if (dispatch) g_main_context_dispatch (context); -#ifdef G_THREADS_ENABLED g_main_context_release (context); -#endif /* G_THREADS_ENABLED */ LOCK_CONTEXT (context); @@ -3099,7 +3713,7 @@ g_main_context_iterate (GMainContext *context, /** * 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. * @@ -3122,22 +3736,22 @@ 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. **/ gboolean @@ -3241,19 +3855,11 @@ g_main_loop_run (GMainLoop *loop) g_return_if_fail (loop != NULL); g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0); -#ifdef G_THREADS_ENABLED if (!g_main_context_acquire (loop->context)) { gboolean got_ownership = FALSE; /* Another thread owns this context */ - if (!g_thread_supported ()) - { - g_warning ("g_main_loop_run() was called from second thread but " - "g_thread_init() was never called."); - return; - } - LOCK_CONTEXT (loop->context); g_atomic_int_inc (&loop->ref_count); @@ -3261,13 +3867,10 @@ g_main_loop_run (GMainLoop *loop) if (!loop->is_running) loop->is_running = TRUE; - if (!loop->context->cond) - loop->context->cond = g_cond_new (); - while (loop->is_running && !got_ownership) got_ownership = g_main_context_wait (loop->context, - loop->context->cond, - g_static_mutex_get_mutex (&loop->context->mutex)); + &loop->context->cond, + &loop->context->mutex); if (!loop->is_running) { @@ -3282,7 +3885,6 @@ g_main_loop_run (GMainLoop *loop) } else LOCK_CONTEXT (loop->context); -#endif /* G_THREADS_ENABLED */ if (loop->context->in_check_or_prepare) { @@ -3298,9 +3900,7 @@ g_main_loop_run (GMainLoop *loop) UNLOCK_CONTEXT (loop->context); -#ifdef G_THREADS_ENABLED g_main_context_release (loop->context); -#endif /* G_THREADS_ENABLED */ g_main_loop_unref (loop); } @@ -3323,12 +3923,9 @@ g_main_loop_quit (GMainLoop *loop) LOCK_CONTEXT (loop->context); loop->is_running = FALSE; - g_main_context_wakeup_unlocked (loop->context); + g_wakeup_signal (loop->context->wakeup); -#ifdef G_THREADS_ENABLED - if (loop->context->cond) - g_cond_broadcast (loop->context->cond); -#endif /* G_THREADS_ENABLED */ + g_cond_broadcast (&loop->context->cond); UNLOCK_CONTEXT (loop->context); } @@ -3356,7 +3953,7 @@ g_main_loop_is_running (GMainLoop *loop) * * Returns the #GMainContext of @loop. * - * Return value: the #GMainContext of @loop + * Return value: (transfer none): the #GMainContext of @loop **/ GMainContext * g_main_loop_get_context (GMainLoop *loop) @@ -3459,16 +4056,16 @@ g_main_context_poll (GMainContext *context, /** * 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, @@ -3523,12 +4120,10 @@ g_main_context_add_poll_unlocked (GMainContext *context, context->n_poll_records++; -#ifdef G_THREADS_ENABLED context->poll_changed = TRUE; /* Now wake up the main loop if it is waiting in the poll() */ - g_main_context_wakeup_unlocked (context); -#endif + g_wakeup_signal (context->wakeup); } /** @@ -3587,24 +4182,19 @@ g_main_context_remove_poll_unlocked (GMainContext *context, pollrec = nextrec; } -#ifdef G_THREADS_ENABLED context->poll_changed = TRUE; /* Now wake up the main loop if it is waiting in the poll() */ - g_main_context_wakeup_unlocked (context); -#endif + g_wakeup_signal (context->wakeup); } /** * g_source_get_current_time: * @source: a #GSource * @timeval: #GTimeVal structure in which to store current time. - * - * Gets the "current time" to be used when checking - * this source. The advantage of calling this function over - * calling g_get_current_time() directly is that when - * checking multiple sources, GLib can cache a single value - * instead of having to repeatedly get the system time. + * + * This function ignores @source and is otherwise the same as + * g_get_current_time(). * * Deprecated: 2.28: use g_source_get_time() instead **/ @@ -3612,24 +4202,7 @@ void g_source_get_current_time (GSource *source, GTimeVal *timeval) { - GMainContext *context; - - g_return_if_fail (source->context != NULL); - - context = source->context; - - LOCK_CONTEXT (context); - - if (!context->real_time_is_fresh) - { - context->real_time = g_get_real_time (); - context->real_time_is_fresh = TRUE; - } - - timeval->tv_sec = context->real_time / 1000000; - timeval->tv_usec = context->real_time % 1000000; - - UNLOCK_CONTEXT (context); + g_get_current_time (timeval); } /** @@ -3730,39 +4303,6 @@ g_main_context_get_poll_func (GMainContext *context) return result; } -static void -_g_main_wake_up_all_contexts (void) -{ - GSList *list; - - /* We were woken up. Wake up all other contexts in all other threads */ - G_LOCK (main_context_list); - for (list = main_context_list; list; list = list->next) - { - GMainContext *context = list->data; - - LOCK_CONTEXT (context); - g_main_context_wakeup_unlocked (context); - UNLOCK_CONTEXT (context); - } - G_UNLOCK (main_context_list); -} - - -/* HOLDS: context's lock */ -/* Wake the main loop up from a poll() */ -static void -g_main_context_wakeup_unlocked (GMainContext *context) -{ -#ifdef G_THREADS_ENABLED - if (g_thread_supported() && context->poll_waiting) - { - context->poll_waiting = FALSE; - g_wakeup_signal (context->wakeup); - } -#endif -} - /** * g_main_context_wakeup: * @context: a #GMainContext @@ -3775,12 +4315,10 @@ g_main_context_wakeup (GMainContext *context) { if (!context) context = g_main_context_default (); - + g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); - LOCK_CONTEXT (context); - g_main_context_wakeup_unlocked (context); - UNLOCK_CONTEXT (context); + g_wakeup_signal (context->wakeup); } /** @@ -3788,7 +4326,7 @@ g_main_context_wakeup (GMainContext *context) * @context: a #GMainContext * * Determines whether this thread holds the (recursive) - * ownership of this #GMaincontext. This is useful to + * ownership of this #GMainContext. This is useful to * know before waiting on another thread that may be * blocking to get ownership of @context. * @@ -3804,13 +4342,9 @@ g_main_context_is_owner (GMainContext *context) if (!context) context = g_main_context_default (); -#ifdef G_THREADS_ENABLED LOCK_CONTEXT (context); is_owner = context->owner == G_THREAD_SELF; UNLOCK_CONTEXT (context); -#else - is_owner = TRUE; -#endif return is_owner; } @@ -3821,8 +4355,9 @@ static void 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) { @@ -3851,42 +4386,17 @@ g_timeout_set_expiration (GTimeoutSource *timeout_source, * 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 @@ -3982,7 +4492,7 @@ g_timeout_source_new_seconds (guint interval) * (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 @@ -4080,7 +4590,7 @@ 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 @@ -4194,7 +4704,6 @@ g_child_watch_prepare (GSource *source, return FALSE; } - static gboolean g_child_watch_check (GSource *source) { @@ -4230,101 +4739,161 @@ g_child_watch_check (GSource *source) return child_exited; } +static void +g_child_watch_finalize (GSource *source) +{ +} + #else /* G_OS_WIN32 */ -static gboolean -check_for_child_exited (GSource *source) +static void +wake_source (GSource *source) { - GChildWatchSource *child_watch_source; - gint count; + GMainContext *context; + + /* This should be thread-safe: + * + * - if the source is currently being added to a context, that + * context will be woken up anyway + * + * - if the source is currently being destroyed, we simply need not + * to crash: + * + * - the memory for the source will remain valid until after the + * source finalize function was called (which would remove the + * source from the global list which we are currently holding the + * lock for) + * + * - the GMainContext will either be NULL or point to a live + * GMainContext + * + * - the GMainContext will remain valid since we hold the + * main_context_list lock + * + * Since we are holding a lot of locks here, don't try to enter any + * more GMainContext functions for fear of dealock -- just hit the + * GWakeup and run. Even if that's safe now, it could easily become + * unsafe with some very minor changes in the future, and signal + * handling is not the most well-tested codepath. + */ + G_LOCK(main_context_list); + context = source->context; + if (context) + g_wakeup_signal (context->wakeup); + G_UNLOCK(main_context_list); +} - /* protect against another SIGCHLD in the middle of this call */ - count = child_watch_count; +static void +dispatch_unix_signals (void) +{ + GSList *node; - child_watch_source = (GChildWatchSource *) source; + /* clear this first incase another one arrives while we're processing */ + any_unix_signal_pending = FALSE; - if (child_watch_source->child_exited) - return TRUE; + G_LOCK(unix_signal_lock); + + /* handle GChildWatchSource instances */ + if (unix_signal_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 + * explicitly watching, so that ties our hands from calling + * waitpid(-1). We also can't use siginfo's si_pid field since if + * multiple SIGCHLD arrive at the same time, one of them can be + * dropped (since a given UNIX signal can only be pending once). + */ + for (node = unix_child_watches; node; node = node->next) + { + GChildWatchSource *source = node->data; + + if (!source->child_exited) + { + pid_t pid; + do + { + 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 (child_watch_source->count < count) + /* handle GUnixSignalWatchSource instances */ + for (node = unix_signal_watches; node; node = node->next) { - gint child_status; + GUnixSignalWatchSource *source = node->data; - if (waitpid (child_watch_source->pid, &child_status, WNOHANG) > 0) - { - child_watch_source->child_status = child_status; - child_watch_source->child_exited = TRUE; - } - child_watch_source->count = count; + if (!source->pending) + { + if (unix_signal_pending[source->signum]) + { + unix_signal_pending[source->signum] = FALSE; + source->pending = TRUE; + + wake_source ((GSource *) source); + } + } } - return child_watch_source->child_exited; + G_UNLOCK(unix_signal_lock); } static gboolean g_child_watch_prepare (GSource *source, gint *timeout) { - *timeout = -1; + GChildWatchSource *child_watch_source; - return check_for_child_exited (source); -} + child_watch_source = (GChildWatchSource *) source; -static gboolean -g_child_watch_check (GSource *source) -{ - return check_for_child_exited (source); + return child_watch_source->child_exited; } static gboolean -check_for_signal_delivery (GSource *source) +g_child_watch_check (GSource *source) { - GUnixSignalWatchSource *unix_signal_source = (GUnixSignalWatchSource*) source; - gboolean delivered; + GChildWatchSource *child_watch_source; - G_LOCK (unix_signal_lock); - if (unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_SINGLE) - { - switch (unix_signal_source->signum) - { - case SIGHUP: - delivered = unix_signal_state.sighup_delivered; - break; - case SIGINT: - delivered = unix_signal_state.sigint_delivered; - break; - case SIGTERM: - delivered = unix_signal_state.sigterm_delivered; - break; - default: - g_assert_not_reached (); - delivered = FALSE; - break; - } - } - else - { - g_assert (unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_THREADED); - delivered = unix_signal_source->pending; - } - G_UNLOCK (unix_signal_lock); + child_watch_source = (GChildWatchSource *) source; - return delivered; + return child_watch_source->child_exited; } static gboolean g_unix_signal_watch_prepare (GSource *source, gint *timeout) { - *timeout = -1; + GUnixSignalWatchSource *unix_signal_source; + + unix_signal_source = (GUnixSignalWatchSource *) source; - return check_for_signal_delivery (source); + return unix_signal_source->pending; } -static gboolean +static gboolean g_unix_signal_watch_check (GSource *source) { - return check_for_signal_delivery (source); + GUnixSignalWatchSource *unix_signal_source; + + unix_signal_source = (GUnixSignalWatchSource *) source; + + return unix_signal_source->pending; } static gboolean @@ -4333,6 +4902,7 @@ g_unix_signal_watch_dispatch (GSource *source, gpointer user_data) { GUnixSignalWatchSource *unix_signal_source; + gboolean again; unix_signal_source = (GUnixSignalWatchSource *) source; @@ -4343,74 +4913,31 @@ g_unix_signal_watch_dispatch (GSource *source, return FALSE; } - (callback) (user_data); - - G_LOCK (unix_signal_lock); - if (unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_SINGLE) - { - switch (unix_signal_source->signum) - { - case SIGHUP: - unix_signal_state.sighup_delivered = FALSE; - break; - case SIGINT: - unix_signal_state.sigint_delivered = FALSE; - break; - case SIGTERM: - unix_signal_state.sigterm_delivered = FALSE; - break; - } - } - else - { - g_assert (unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_THREADED); - unix_signal_source->pending = FALSE; - } - G_UNLOCK (unix_signal_lock); + again = (callback) (user_data); - return TRUE; + unix_signal_source->pending = FALSE; + + return again; } static void ensure_unix_signal_handler_installed_unlocked (int signum) { + static sigset_t installed_signal_mask; + static gboolean initialized; struct sigaction action; - GError *error = NULL; - if (unix_signal_init_state == UNIX_SIGNAL_UNINITIALIZED) + if (!initialized) { - sigemptyset (&unix_signal_mask); - } - - if (unix_signal_init_state == UNIX_SIGNAL_UNINITIALIZED - || unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_SINGLE) - { - if (!g_thread_supported ()) - { - /* There is nothing to do for initializing in the non-threaded - * case. - */ - if (unix_signal_init_state == UNIX_SIGNAL_UNINITIALIZED) - unix_signal_init_state = UNIX_SIGNAL_INITIALIZED_SINGLE; - } - else - { - if (!g_unix_open_pipe (unix_signal_wake_up_pipe, FD_CLOEXEC, &error)) - g_error ("Cannot create UNIX signal wake up pipe: %s\n", error->message); - g_unix_set_fd_nonblocking (unix_signal_wake_up_pipe[1], TRUE, NULL); - - /* We create a helper thread that polls on the wakeup pipe indefinitely */ - if (g_thread_create (unix_signal_helper_thread, NULL, FALSE, &error) == NULL) - g_error ("Cannot create a thread to monitor UNIX signals: %s\n", error->message); - - unix_signal_init_state = UNIX_SIGNAL_INITIALIZED_THREADED; - } + sigemptyset (&installed_signal_mask); + g_get_worker_context (); + initialized = TRUE; } - if (sigismember (&unix_signal_mask, signum)) + if (sigismember (&installed_signal_mask, signum)) return; - sigaddset (&unix_signal_mask, signum); + sigaddset (&installed_signal_mask, signum); action.sa_handler = g_unix_signal_handler; sigemptyset (&action.sa_mask); @@ -4433,12 +4960,15 @@ _g_main_create_unix_signal_watch (int signum) G_LOCK (unix_signal_lock); ensure_unix_signal_handler_installed_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; G_UNLOCK (unix_signal_lock); return source; } -static void +static void g_unix_signal_watch_finalize (GSource *source) { G_LOCK (unix_signal_lock); @@ -4446,6 +4976,14 @@ g_unix_signal_watch_finalize (GSource *source) G_UNLOCK (unix_signal_lock); } +static void +g_child_watch_finalize (GSource *source) +{ + G_LOCK (unix_signal_lock); + unix_child_watches = g_slist_remove (unix_child_watches, source); + G_UNLOCK (unix_signal_lock); +} + #endif /* G_OS_WIN32 */ static gboolean @@ -4476,149 +5014,10 @@ g_child_watch_dispatch (GSource *source, static void g_unix_signal_handler (int signum) { - if (signum == SIGCHLD) - child_watch_count ++; - - if (unix_signal_init_state == UNIX_SIGNAL_INITIALIZED_THREADED) - { - char buf[1]; - switch (signum) - { - case SIGCHLD: - buf[0] = _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR; - break; - case SIGHUP: - buf[0] = _UNIX_SIGNAL_PIPE_SIGHUP_CHAR; - break; - case SIGINT: - buf[0] = _UNIX_SIGNAL_PIPE_SIGINT_CHAR; - break; - case SIGTERM: - buf[0] = _UNIX_SIGNAL_PIPE_SIGTERM_CHAR; - break; - default: - /* Shouldn't happen */ - return; - } - write (unix_signal_wake_up_pipe[1], buf, 1); - } - else - { - /* We count on the signal interrupting the poll in the same thread. */ - switch (signum) - { - case SIGCHLD: - /* Nothing to do - the handler will call waitpid() */ - break; - case SIGHUP: - unix_signal_state.sighup_delivered = TRUE; - break; - case SIGINT: - unix_signal_state.sigint_delivered = TRUE; - break; - case SIGTERM: - unix_signal_state.sigterm_delivered = TRUE; - break; - default: - g_assert_not_reached (); - break; - } - } -} - -static void -deliver_unix_signal (int signum) -{ - GSList *iter; - g_assert (signum == SIGHUP || signum == SIGINT || signum == SIGTERM); - - G_LOCK (unix_signal_lock); - for (iter = unix_signal_watches; iter; iter = iter->next) - { - GUnixSignalWatchSource *source = iter->data; - - if (source->signum != signum) - continue; - - source->pending = TRUE; - } - G_UNLOCK (unix_signal_lock); -} - -/* - * This thread is created whenever anything in GLib needs - * to deal with UNIX signals; at present, just SIGCHLD - * from g_child_watch_source_new(). - * - * Note: We could eventually make this thread a more public interface - * and allow e.g. GDBus to use it instead of its own worker thread. - */ -static gpointer -unix_signal_helper_thread (gpointer data) -{ - while (1) - { - gchar b[128]; - ssize_t i, bytes_read; - gboolean sigterm_received = FALSE; - gboolean sigint_received = FALSE; - gboolean sighup_received = FALSE; - - bytes_read = read (unix_signal_wake_up_pipe[0], b, sizeof (b)); - if (bytes_read < 0) - { - g_warning ("Failed to read from child watch wake up pipe: %s", - strerror (errno)); - /* Not much we can do here sanely; just wait a second and hope - * it was transient. - */ - g_usleep (G_USEC_PER_SEC); - continue; - } - for (i = 0; i < bytes_read; i++) - { - switch (b[i]) - { - case _UNIX_SIGNAL_PIPE_SIGCHLD_CHAR: - /* The child watch source will call waitpid() in its - * prepare() and check() methods; however, we don't - * know which pid exited, so we need to wake up - * all contexts. Note: actually we could get the pid - * from the "siginfo_t" via the handler, but to pass - * that info down the pipe would require a more structured - * data stream (as opposed to a single byte). - */ - break; - case _UNIX_SIGNAL_PIPE_SIGTERM_CHAR: - sigterm_received = TRUE; - break; - case _UNIX_SIGNAL_PIPE_SIGHUP_CHAR: - sighup_received = TRUE; - break; - case _UNIX_SIGNAL_PIPE_SIGINT_CHAR: - sigint_received = TRUE; - break; - default: - g_warning ("Invalid char '%c' read from child watch pipe", b[i]); - break; - } - } - if (sigterm_received) - deliver_unix_signal (SIGTERM); - if (sigint_received) - deliver_unix_signal (SIGINT); - if (sighup_received) - deliver_unix_signal (SIGHUP); - _g_main_wake_up_all_contexts (); - } -} + unix_signal_pending[signum] = TRUE; + any_unix_signal_pending = TRUE; -static void -g_child_watch_source_init (void) -{ - G_LOCK (unix_signal_lock); - ensure_unix_signal_handler_installed_unlocked (SIGCHLD); - G_UNLOCK (unix_signal_lock); + g_wakeup_signal (glib_worker_context->wakeup); } #endif /* !G_OS_WIN32 */ @@ -4643,10 +5042,10 @@ g_child_watch_source_init (void) * 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 waitpid(-1) in - * the application. Calling waitpid() for individual pids will - * still work fine. + * 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. * * Return value: the newly-created child watch source * @@ -4658,17 +5057,22 @@ g_child_watch_source_new (GPid pid) GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource)); GChildWatchSource *child_watch_source = (GChildWatchSource *)source; + child_watch_source->pid = pid; + #ifdef G_OS_WIN32 child_watch_source->poll.fd = (gintptr) pid; child_watch_source->poll.events = G_IO_IN; g_source_add_poll (source, &child_watch_source->poll); #else /* G_OS_WIN32 */ - g_child_watch_source_init (); + G_LOCK (unix_signal_lock); + ensure_unix_signal_handler_installed_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_UNLOCK (unix_signal_lock); #endif /* G_OS_WIN32 */ - child_watch_source->pid = pid; - return source; } @@ -4680,7 +5084,7 @@ g_child_watch_source_new (GPid pid) * 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. @@ -4688,11 +5092,15 @@ g_child_watch_source_new (GPid pid) * 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. * @@ -4831,7 +5239,7 @@ 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 @@ -4907,7 +5315,7 @@ g_idle_remove_by_data (gpointer data) /** * g_main_context_invoke: - * @context: a #GMainContext, or %NULL + * @context: (allow-none): a #GMainContext, or %NULL * @function: function to call * @data: data to pass to @function * @@ -4947,11 +5355,11 @@ g_main_context_invoke (GMainContext *context, /** * g_main_context_invoke_full: - * @context: a #GMainContext, or %NULL + * @context: (allow-none): a #GMainContext, or %NULL * @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. @@ -5014,3 +5422,45 @@ g_main_context_invoke_full (GMainContext *context, } } } + +static gpointer +glib_worker_main (gpointer data) +{ + while (TRUE) + { + g_main_context_iteration (glib_worker_context, TRUE); + +#ifdef G_OS_UNIX + if (any_unix_signal_pending) + dispatch_unix_signals (); +#endif + } + + return NULL; /* worst GCC warning message ever... */ +} + +GMainContext * +g_get_worker_context (void) +{ + static gsize initialised; + + if (g_once_init_enter (&initialised)) + { + /* 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 (); + 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); + } + + return glib_worker_context; +}