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Diffstat (limited to 'protocols/Sametime/src/glib/gmain.c')
| -rw-r--r-- | protocols/Sametime/src/glib/gmain.c | 4358 |
1 files changed, 4358 insertions, 0 deletions
diff --git a/protocols/Sametime/src/glib/gmain.c b/protocols/Sametime/src/glib/gmain.c new file mode 100644 index 0000000000..91e2a8e378 --- /dev/null +++ b/protocols/Sametime/src/glib/gmain.c @@ -0,0 +1,4358 @@ +/* GLIB - Library of useful routines for C programming + * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald + * + * gmain.c: Main loop abstraction, timeouts, and idle functions + * Copyright 1998 Owen Taylor + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +/* + * Modified by the GLib Team and others 1997-2000. See the AUTHORS + * file for a list of people on the GLib Team. See the ChangeLog + * files for a list of changes. These files are distributed with + * GLib at ftp://ftp.gtk.org/pub/gtk/. + */ + +/* + * MT safe + */ + +#ifndef _WIN32 +/* for pipe2; need to define it first to avoid + * other headers pulling in unistd.h + */ +/* The meaning of_GNU_SOURCE that is intended here is present only on + * Linux; avoid the possibility that some misguided header in MinGW + * looks at it. Ideally we should define _GNU_SOURCE only on platforms + * where we know what it means and that is what we want here + * (i.e. Linux with glibc). After all, there might be some other POSIX + * platform even where _GNU_SOURCE is used for some unrelated change + * in semantics that isn't wanted. Sigh. + */ +#define _GNU_SOURCE +#endif + +#include "config.h" +#include "glibconfig.h" + +/* Uncomment the next line (and the corresponding line in gpoll.c) to + * enable debugging printouts if the environment variable + * G_MAIN_POLL_DEBUG is set to some value. + */ +/* #define G_MAIN_POLL_DEBUG */ + +#ifdef _WIN32 +/* Always enable debugging printout on Windows, as it is more often + * needed there... + */ +#define G_MAIN_POLL_DEBUG +#endif + +#include <signal.h> +#include <sys/types.h> +#include <time.h> +#include <stdlib.h> +#ifdef HAVE_SYS_TIME_H +#include <sys/time.h> +#endif /* HAVE_SYS_TIME_H */ +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif /* HAVE_UNISTD_H */ +#include <errno.h> + +#ifdef G_OS_WIN32 +#define STRICT +#include <windows.h> +#endif /* G_OS_WIN32 */ + +#ifdef G_OS_BEOS +#include <sys/socket.h> +#include <sys/wait.h> +#endif /* G_OS_BEOS */ + +#ifdef G_OS_UNIX +#include <fcntl.h> +#include <sys/wait.h> +#endif + +#include "gmain.h" + +#include "garray.h" +#include "giochannel.h" +#include "ghash.h" +#include "ghook.h" +#include "gqueue.h" +#include "gstrfuncs.h" +#include "gtestutils.h" +#include "gthreadprivate.h" + +#ifdef G_OS_WIN32 +#include "gwin32.h" +#endif + +#ifdef G_MAIN_POLL_DEBUG +#include "gtimer.h" +#endif + +/** + * SECTION:main + * @title: The Main Event Loop + * @short_description: manages all available sources of events + * + * The main event loop manages all the available sources of events for + * GLib and GTK+ applications. These events can come from any number of + * different types of sources such as file descriptors (plain files, + * pipes or sockets) and timeouts. New types of event sources can also + * be added using g_source_attach(). + * + * To allow multiple independent sets of sources to be handled in + * different threads, each source is associated with a #GMainContext. + * A GMainContext can only be running in a single thread, but + * sources can be added to it and removed from it from other threads. + * + * Each event source is assigned a priority. The default priority, + * #G_PRIORITY_DEFAULT, is 0. Values less than 0 denote higher priorities. + * Values greater than 0 denote lower priorities. Events from high priority + * sources are always processed before events from lower priority sources. + * + * Idle functions can also be added, and assigned a priority. These will + * be run whenever no events with a higher priority are ready to be processed. + * + * The #GMainLoop data type represents a main event loop. A GMainLoop is + * created with g_main_loop_new(). After adding the initial event sources, + * g_main_loop_run() is called. This continuously checks for new events from + * each of the event sources and dispatches them. Finally, the processing of + * an event from one of the sources leads to a call to g_main_loop_quit() to + * exit the main loop, and g_main_loop_run() returns. + * + * It is possible to create new instances of #GMainLoop recursively. + * This is often used in GTK+ applications when showing modal dialog + * boxes. Note that event sources are associated with a particular + * #GMainContext, and will be checked and dispatched for all main + * loops associated with that GMainContext. + * + * GTK+ contains wrappers of some of these functions, e.g. gtk_main(), + * gtk_main_quit() and gtk_events_pending(). + * + * <refsect2><title>Creating new source types</title> + * <para>One of the unusual features of the #GMainLoop functionality + * is that new types of event source can be created and used in + * addition to the builtin type of event source. A new event source + * type is used for handling GDK events. A new source type is created + * by <firstterm>deriving</firstterm> from the #GSource structure. + * The derived type of source is represented by a structure that has + * the #GSource structure as a first element, and other elements specific + * to the new source type. To create an instance of the new source type, + * call g_source_new() passing in the size of the derived structure and + * a table of functions. These #GSourceFuncs determine the behavior of + * the new source type.</para> + * <para>New source types basically interact with the main context + * in two ways. Their prepare function in #GSourceFuncs can set a timeout + * to determine the maximum amount of time that the main loop will sleep + * before checking the source again. In addition, or as well, the source + * can add file descriptors to the set that the main context checks using + * g_source_add_poll().</para> + * </refsect2> + * <refsect2><title>Customizing the main loop iteration</title> + * <para>Single iterations of a #GMainContext can be run with + * g_main_context_iteration(). In some cases, more detailed control + * of exactly how the details of the main loop work is desired, for + * instance, when integrating the #GMainLoop with an external main loop. + * In such cases, you can call the component functions of + * g_main_context_iteration() directly. These functions are + * g_main_context_prepare(), g_main_context_query(), + * g_main_context_check() and g_main_context_dispatch().</para> + * <para>The operation of these functions can best be seen in terms + * of a state diagram, as shown in <xref linkend="mainloop-states"/>.</para> + * <figure id="mainloop-states"><title>States of a Main Context</title> + * <graphic fileref="mainloop-states.gif" format="GIF"></graphic> + * </figure> + * </refsect2> + */ + +/* Types */ + +typedef struct _GTimeoutSource GTimeoutSource; +typedef struct _GChildWatchSource GChildWatchSource; +typedef struct _GPollRec GPollRec; +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) +} GSourceFlags; + +#ifdef G_THREADS_ENABLED +typedef struct _GMainWaiter GMainWaiter; + +struct _GMainWaiter +{ + GCond *cond; + GMutex *mutex; +}; +#endif + +typedef struct _GMainDispatch GMainDispatch; + +struct _GMainDispatch +{ + gint depth; + GSList *dispatching_sources; /* stack of current sources */ +}; + +#ifdef G_MAIN_POLL_DEBUG +gboolean _g_main_poll_debug = FALSE; +#endif + +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; + GThread *owner; + guint owner_count; + GSList *waiters; +#endif + + gint ref_count; + + GPtrArray *pending_dispatches; + gint timeout; /* Timeout for current iteration */ + + guint next_id; + GSource *source_list; + gint in_check_or_prepare; + + GPollRec *poll_records; + guint n_poll_records; + GPollFD *cached_poll_array; + guint cached_poll_array_size; + +#ifdef G_THREADS_ENABLED +#ifndef G_OS_WIN32 +/* this pipe is used to wake up the main loop when a source is added. + */ + gint wake_up_pipe[2]; +#else /* G_OS_WIN32 */ + HANDLE wake_up_semaphore; +#endif /* G_OS_WIN32 */ + + 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; + + GTimeVal current_time; + gboolean time_is_current; +}; + +struct _GSourceCallback +{ + guint ref_count; + GSourceFunc func; + gpointer data; + GDestroyNotify notify; +}; + +struct _GMainLoop +{ + GMainContext *context; + gboolean is_running; + gint ref_count; +}; + +struct _GTimeoutSource +{ + GSource source; + GTimeVal expiration; + guint interval; + guint granularity; +}; + +struct _GChildWatchSource +{ + GSource source; + GPid pid; + gint child_status; +#ifdef G_OS_WIN32 + GPollFD poll; +#else /* G_OS_WIN32 */ + gint count; + gboolean child_exited; +#endif /* G_OS_WIN32 */ +}; + +struct _GPollRec +{ + GPollFD *fd; + GPollRec *next; + gint priority; +}; + +#ifdef G_THREADS_ENABLED +#define LOCK_CONTEXT(context) g_static_mutex_lock (&context->mutex) +#define UNLOCK_CONTEXT(context) g_static_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_UNREF(source, context) \ + G_STMT_START { \ + if ((source)->ref_count > 1) \ + (source)->ref_count--; \ + else \ + g_source_unref_internal ((source), (context), TRUE); \ + } G_STMT_END + + +/* Forward declarations */ + +static void g_source_unref_internal (GSource *source, + GMainContext *context, + gboolean have_lock); +static void g_source_destroy_internal (GSource *source, + GMainContext *context, + gboolean have_lock); +static void g_main_context_poll (GMainContext *context, + gint timeout, + gint priority, + GPollFD *fds, + gint n_fds); +static void g_main_context_add_poll_unlocked (GMainContext *context, + gint priority, + GPollFD *fd); +static void g_main_context_remove_poll_unlocked (GMainContext *context, + GPollFD *fd); +static void g_main_context_wakeup_unlocked (GMainContext *context); + +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); +static gboolean g_child_watch_prepare (GSource *source, + gint *timeout); +static gboolean g_child_watch_check (GSource *source); +static gboolean g_child_watch_dispatch (GSource *source, + GSourceFunc callback, + gpointer user_data); +static gboolean g_idle_prepare (GSource *source, + gint *timeout); +static gboolean g_idle_check (GSource *source); +static gboolean g_idle_dispatch (GSource *source, + GSourceFunc callback, + gpointer user_data); + +G_LOCK_DEFINE_STATIC (main_loop); +static GMainContext *default_main_context; +static GSList *main_contexts_without_pipe = NULL; + +#ifndef G_OS_WIN32 +/* Child status monitoring code */ +enum { + CHILD_WATCH_UNINITIALIZED, + CHILD_WATCH_INITIALIZED_SINGLE, + CHILD_WATCH_INITIALIZED_THREADED +}; +static gint child_watch_init_state = CHILD_WATCH_UNINITIALIZED; +static gint child_watch_count = 1; +static gint child_watch_wake_up_pipe[2] = {0, 0}; +#endif /* !G_OS_WIN32 */ +G_LOCK_DEFINE_STATIC (main_context_list); +static GSList *main_context_list = NULL; + +static gint timer_perturb = -1; + +GSourceFuncs g_timeout_funcs = +{ + g_timeout_prepare, + g_timeout_check, + g_timeout_dispatch, + NULL +}; + +GSourceFuncs g_child_watch_funcs = +{ + g_child_watch_prepare, + g_child_watch_check, + g_child_watch_dispatch, + NULL +}; + +GSourceFuncs g_idle_funcs = +{ + g_idle_prepare, + g_idle_check, + g_idle_dispatch, + NULL +}; + +/** + * g_main_context_ref: + * @context: a #GMainContext + * + * Increases the reference count on a #GMainContext object by one. + * + * Returns: the @context that was passed in (since 2.6) + **/ +GMainContext * +g_main_context_ref (GMainContext *context) +{ + g_return_val_if_fail (context != NULL, NULL); + g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL); + + g_atomic_int_inc (&context->ref_count); + + return context; +} + +static inline void +poll_rec_list_free (GMainContext *context, + GPollRec *list) +{ + g_slice_free_chain (GPollRec, list, next); +} + +/** + * g_main_context_unref: + * @context: a #GMainContext + * + * Decreases the reference count on a #GMainContext object by one. If + * the result is zero, free the context and free all associated memory. + **/ +void +g_main_context_unref (GMainContext *context) +{ + GSource *source; + g_return_if_fail (context != NULL); + g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); + + if (!g_atomic_int_dec_and_test (&context->ref_count)) + return; + + G_LOCK (main_context_list); + main_context_list = g_slist_remove (main_context_list, context); + G_UNLOCK (main_context_list); + + source = context->source_list; + while (source) + { + GSource *next = source->next; + g_source_destroy_internal (source, context, FALSE); + source = next; + } + +#ifdef G_THREADS_ENABLED + g_static_mutex_free (&context->mutex); +#endif + + 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()) + { +#ifndef G_OS_WIN32 + close (context->wake_up_pipe[0]); + close (context->wake_up_pipe[1]); +#else + CloseHandle (context->wake_up_semaphore); +#endif + } + else + main_contexts_without_pipe = g_slist_remove (main_contexts_without_pipe, + context); + + if (context->cond != NULL) + g_cond_free (context->cond); +#endif + + g_free (context); +} + +#ifdef G_THREADS_ENABLED +static void +g_main_context_init_pipe (GMainContext *context) +{ +# ifndef G_OS_WIN32 + if (context->wake_up_pipe[0] != -1) + return; + +#ifdef HAVE_PIPE2 + /* if this fails, we fall through and try pipe */ + pipe2 (context->wake_up_pipe, O_CLOEXEC); +#endif + if (context->wake_up_pipe[0] == -1) + { + if (pipe (context->wake_up_pipe) < 0) + g_error ("Cannot create pipe main loop wake-up: %s\n", + g_strerror (errno)); + + fcntl (context->wake_up_pipe[0], F_SETFD, FD_CLOEXEC); + fcntl (context->wake_up_pipe[1], F_SETFD, FD_CLOEXEC); + } + + context->wake_up_rec.fd = context->wake_up_pipe[0]; + context->wake_up_rec.events = G_IO_IN; +# else + if (context->wake_up_semaphore != NULL) + return; + context->wake_up_semaphore = CreateSemaphore (NULL, 0, 100, NULL); + if (context->wake_up_semaphore == NULL) + g_error ("Cannot create wake-up semaphore: %s", + g_win32_error_message (GetLastError ())); + context->wake_up_rec.fd = (gintptr) context->wake_up_semaphore; + context->wake_up_rec.events = G_IO_IN; + + if (_g_main_poll_debug) + g_print ("wake-up semaphore: %p\n", context->wake_up_semaphore); +# endif + g_main_context_add_poll_unlocked (context, 0, &context->wake_up_rec); +} + +void +_g_main_thread_init (void) +{ + GSList *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; +} +#endif /* G_THREADS_ENABLED */ + +/** + * g_main_context_new: + * + * Creates a new #GMainContext structure. + * + * Return value: the new #GMainContext + **/ +GMainContext * +g_main_context_new (void) +{ + GMainContext *context = g_new0 (GMainContext, 1); + +#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; + } + } +#endif + +#ifdef G_THREADS_ENABLED + g_static_mutex_init (&context->mutex); + + context->owner = NULL; + context->waiters = NULL; + +# ifndef G_OS_WIN32 + context->wake_up_pipe[0] = -1; + context->wake_up_pipe[1] = -1; +# else + context->wake_up_semaphore = NULL; +# endif +#endif + + context->ref_count = 1; + + context->next_id = 1; + + context->source_list = NULL; + + context->poll_func = g_poll; + + context->cached_poll_array = NULL; + context->cached_poll_array_size = 0; + + context->pending_dispatches = g_ptr_array_new (); + + context->time_is_current = 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 + + G_LOCK (main_context_list); + main_context_list = g_slist_append (main_context_list, context); + +#ifdef G_MAIN_POLL_DEBUG + if (_g_main_poll_debug) + g_print ("created context=%p\n", context); +#endif + + G_UNLOCK (main_context_list); + + return context; +} + +/** + * g_main_context_default: + * + * Returns the global default main context. This is the main context + * used for main loop functions when a main loop is not explicitly + * specified, and corresponds to the "main" main loop. See also + * g_main_context_get_thread_default(). + * + * Return value: the global default main context. + **/ +GMainContext * +g_main_context_default (void) +{ + /* Slow, but safe */ + + G_LOCK (main_loop); + + if (!default_main_context) + { + default_main_context = g_main_context_new (); +#ifdef G_MAIN_POLL_DEBUG + if (_g_main_poll_debug) + g_print ("default context=%p\n", default_main_context); +#endif + } + + G_UNLOCK (main_loop); + + return default_main_context; +} + +static GStaticPrivate thread_context_stack = G_STATIC_PRIVATE_INIT; + +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_main_context_push_thread_default: + * @context: a #GMainContext, or %NULL for the global default context + * + * Acquires @context and sets it as the thread-default context for the + * current thread. This will cause certain asynchronous operations + * (such as most <link linkend="gio">gio</link>-based I/O) which are + * started in this thread to run under @context and deliver their + * results to its main loop, rather than running under the global + * default context in the main thread. Note that calling this function + * changes the context returned by + * g_main_context_get_thread_default(), <emphasis>not</emphasis> the + * one returned by g_main_context_default(), so it does not affect the + * context used by functions like g_idle_add(). + * + * Normally you would call this function shortly after creating a new + * thread, passing it a #GMainContext which will be run by a + * #GMainLoop in that thread, to set a new default context for all + * async operations in that thread. (In this case, you don't need to + * ever call g_main_context_pop_thread_default().) In some cases + * however, you may want to schedule a single operation in a + * non-default context, or temporarily use a non-default context in + * the main thread. In that case, you can wrap the call to the + * asynchronous operation inside a + * g_main_context_push_thread_default() / + * g_main_context_pop_thread_default() pair, but it is up to you to + * ensure that no other asynchronous operations accidentally get + * started while the non-default context is active. + * + * Beware that libraries that predate this function may not correctly + * handle being used from a thread with a thread-default context. Eg, + * see g_file_supports_thread_contexts(). + * + * Since: 2.22 + **/ +void +g_main_context_push_thread_default (GMainContext *context) +{ + GQueue *stack; + gboolean acquired_context; + + acquired_context = g_main_context_acquire (context); + g_return_if_fail (acquired_context); + + if (context == g_main_context_default ()) + context = NULL; + else if (context) + g_main_context_ref (context); + + stack = g_static_private_get (&thread_context_stack); + if (!stack) + { + stack = g_queue_new (); + g_static_private_set (&thread_context_stack, stack, + free_context_stack); + } + + g_queue_push_head (stack, context); +} + +/** + * g_main_context_pop_thread_default: + * @context: a #GMainContext object, or %NULL + * + * Pops @context off the thread-default context stack (verifying that + * it was on the top of the stack). + * + * Since: 2.22 + **/ +void +g_main_context_pop_thread_default (GMainContext *context) +{ + GQueue *stack; + + if (context == g_main_context_default ()) + context = NULL; + + stack = g_static_private_get (&thread_context_stack); + + g_return_if_fail (stack != NULL); + g_return_if_fail (g_queue_peek_head (stack) == context); + + g_queue_pop_head (stack); + + g_main_context_release (context); + if (context) + g_main_context_unref (context); +} + +/** + * g_main_context_get_thread_default: + * + * 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 #GSource<!-- -->s 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.) + * + * Returns: the thread-default #GMainContext, or %NULL if the + * thread-default context is the global default context. + * + * Since: 2.22 + **/ +GMainContext * +g_main_context_get_thread_default (void) +{ + GQueue *stack; + + stack = g_static_private_get (&thread_context_stack); + if (stack) + return g_queue_peek_head (stack); + else + return NULL; +} + +/* Hooks for adding to the main loop */ + +/** + * g_source_new: + * @source_funcs: structure containing functions that implement + * the sources behavior. + * @struct_size: size of the #GSource structure to create. + * + * Creates a new #GSource structure. The size is specified to + * allow creating structures derived from #GSource that contain + * additional data. The size passed in must be at least + * <literal>sizeof (GSource)</literal>. + * + * The source will not initially be associated with any #GMainContext + * and must be added to one with g_source_attach() before it will be + * executed. + * + * Return value: the newly-created #GSource. + **/ +GSource * +g_source_new (GSourceFuncs *source_funcs, + guint struct_size) +{ + GSource *source; + + g_return_val_if_fail (source_funcs != NULL, NULL); + g_return_val_if_fail (struct_size >= sizeof (GSource), NULL); + + source = (GSource*) g_malloc0 (struct_size); + + source->source_funcs = source_funcs; + source->ref_count = 1; + + source->priority = G_PRIORITY_DEFAULT; + + source->flags = G_HOOK_FLAG_ACTIVE; + + /* NULL/0 initialization for all other fields */ + + return source; +} + +/* Holds context's lock + */ +static void +g_source_list_add (GSource *source, + GMainContext *context) +{ + GSource *tmp_source, *last_source; + + 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; + } + + source->next = tmp_source; + if (tmp_source) + tmp_source->prev = source; + + source->prev = last_source; + if (last_source) + last_source->next = source; + else + context->source_list = source; +} + +/* Holds context's lock + */ +static void +g_source_list_remove (GSource *source, + GMainContext *context) +{ + if (source->prev) + source->prev->next = source->next; + else + context->source_list = source->next; + + if (source->next) + source->next->prev = source->prev; + + source->prev = NULL; + source->next = NULL; +} + +/** + * g_source_attach: + * @source: a #GSource + * @context: a #GMainContext (if %NULL, the default context will be used) + * + * Adds a #GSource to a @context so that it will be executed within + * that context. Remove it by calling g_source_destroy(). + * + * Return value: the ID (greater than 0) for the source within the + * #GMainContext. + **/ +guint +g_source_attach (GSource *source, + GMainContext *context) +{ + guint result = 0; + GSList *tmp_list; + + g_return_val_if_fail (source->context == NULL, 0); + g_return_val_if_fail (!SOURCE_DESTROYED (source), 0); + + if (!context) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + source->context = context; + result = source->source_id = context->next_id++; + + source->ref_count++; + g_source_list_add (source, context); + + tmp_list = source->poll_fds; + while (tmp_list) + { + g_main_context_add_poll_unlocked (context, source->priority, tmp_list->data); + tmp_list = tmp_list->next; + } + +#ifdef G_THREADS_ENABLED + /* Now wake up the main loop if it is waiting in the poll() */ + g_main_context_wakeup_unlocked (context); +#endif + + UNLOCK_CONTEXT (context); + + return result; +} + +static void +g_source_destroy_internal (GSource *source, + GMainContext *context, + gboolean have_lock) +{ + if (!have_lock) + LOCK_CONTEXT (context); + + if (!SOURCE_DESTROYED (source)) + { + GSList *tmp_list; + gpointer old_cb_data; + GSourceCallbackFuncs *old_cb_funcs; + + source->flags &= ~G_HOOK_FLAG_ACTIVE; + + old_cb_data = source->callback_data; + old_cb_funcs = source->callback_funcs; + + source->callback_data = NULL; + source->callback_funcs = NULL; + + if (old_cb_funcs) + { + UNLOCK_CONTEXT (context); + old_cb_funcs->unref (old_cb_data); + LOCK_CONTEXT (context); + } + + if (!SOURCE_BLOCKED (source)) + { + tmp_list = source->poll_fds; + while (tmp_list) + { + g_main_context_remove_poll_unlocked (context, tmp_list->data); + tmp_list = tmp_list->next; + } + } + + g_source_unref_internal (source, context, TRUE); + } + + if (!have_lock) + UNLOCK_CONTEXT (context); +} + +/** + * g_source_destroy: + * @source: a #GSource + * + * Removes a source from its #GMainContext, if any, and mark it as + * destroyed. The source cannot be subsequently added to another + * context. + **/ +void +g_source_destroy (GSource *source) +{ + GMainContext *context; + + g_return_if_fail (source != NULL); + + context = source->context; + + if (context) + g_source_destroy_internal (source, context, FALSE); + else + source->flags &= ~G_HOOK_FLAG_ACTIVE; +} + +/** + * g_source_get_id: + * @source: a #GSource + * + * Returns the numeric ID for a particular source. The ID of a source + * is a positive integer which is unique within a particular main loop + * context. The reverse + * mapping from ID to source is done by g_main_context_find_source_by_id(). + * + * Return value: the ID (greater than 0) for the source + **/ +guint +g_source_get_id (GSource *source) +{ + guint result; + + g_return_val_if_fail (source != NULL, 0); + g_return_val_if_fail (source->context != NULL, 0); + + LOCK_CONTEXT (source->context); + result = source->source_id; + UNLOCK_CONTEXT (source->context); + + return result; +} + +/** + * g_source_get_context: + * @source: a #GSource + * + * Gets the #GMainContext with which the source is associated. + * Calling this function on a destroyed source 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. + **/ +GMainContext * +g_source_get_context (GSource *source) +{ + g_return_val_if_fail (!SOURCE_DESTROYED (source), NULL); + + return source->context; +} + +/** + * g_source_add_poll: + * @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. + **/ +void +g_source_add_poll (GSource *source, + GPollFD *fd) +{ + GMainContext *context; + + g_return_if_fail (source != NULL); + g_return_if_fail (fd != NULL); + g_return_if_fail (!SOURCE_DESTROYED (source)); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + source->poll_fds = g_slist_prepend (source->poll_fds, fd); + + if (context) + { + if (!SOURCE_BLOCKED (source)) + g_main_context_add_poll_unlocked (context, source->priority, fd); + UNLOCK_CONTEXT (context); + } +} + +/** + * g_source_remove_poll: + * @source:a #GSource + * @fd: a #GPollFD structure previously passed to g_source_add_poll(). + * + * Removes a file descriptor from the set of file descriptors polled for + * this source. + **/ +void +g_source_remove_poll (GSource *source, + GPollFD *fd) +{ + GMainContext *context; + + g_return_if_fail (source != NULL); + g_return_if_fail (fd != NULL); + g_return_if_fail (!SOURCE_DESTROYED (source)); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + source->poll_fds = g_slist_remove (source->poll_fds, fd); + + if (context) + { + if (!SOURCE_BLOCKED (source)) + g_main_context_remove_poll_unlocked (context, fd); + UNLOCK_CONTEXT (context); + } +} + +/** + * g_source_set_callback_indirect: + * @source: the source + * @callback_data: pointer to callback data "object" + * @callback_funcs: functions for reference counting @callback_data + * and getting the callback and data + * + * Sets the callback function storing the data as a refcounted callback + * "object". This is used internally. Note that calling + * g_source_set_callback_indirect() assumes + * an initial reference count on @callback_data, and thus + * @callback_funcs->unref will eventually be called once more + * than @callback_funcs->ref. + **/ +void +g_source_set_callback_indirect (GSource *source, + gpointer callback_data, + GSourceCallbackFuncs *callback_funcs) +{ + GMainContext *context; + gpointer old_cb_data; + GSourceCallbackFuncs *old_cb_funcs; + + g_return_if_fail (source != NULL); + g_return_if_fail (callback_funcs != NULL || callback_data == NULL); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + old_cb_data = source->callback_data; + old_cb_funcs = source->callback_funcs; + + source->callback_data = callback_data; + source->callback_funcs = callback_funcs; + + if (context) + UNLOCK_CONTEXT (context); + + if (old_cb_funcs) + old_cb_funcs->unref (old_cb_data); +} + +static void +g_source_callback_ref (gpointer cb_data) +{ + GSourceCallback *callback = cb_data; + + callback->ref_count++; +} + + +static void +g_source_callback_unref (gpointer cb_data) +{ + GSourceCallback *callback = cb_data; + + callback->ref_count--; + if (callback->ref_count == 0) + { + if (callback->notify) + callback->notify (callback->data); + g_free (callback); + } +} + +static void +g_source_callback_get (gpointer cb_data, + GSource *source, + GSourceFunc *func, + gpointer *data) +{ + GSourceCallback *callback = cb_data; + + *func = callback->func; + *data = callback->data; +} + +static GSourceCallbackFuncs g_source_callback_funcs = { + g_source_callback_ref, + g_source_callback_unref, + g_source_callback_get, +}; + +/** + * g_source_set_callback: + * @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. + * + * Sets the callback function for a source. The callback for a source is + * called from the source's dispatch function. + * + * The exact type of @func depends on the type of source; ie. you + * should not count on @func being called with @data as its first + * parameter. + * + * Typically, you won't use this function. Instead use functions specific + * to the type of source you are using. + **/ +void +g_source_set_callback (GSource *source, + GSourceFunc func, + gpointer data, + GDestroyNotify notify) +{ + GSourceCallback *new_callback; + + g_return_if_fail (source != NULL); + + new_callback = g_new (GSourceCallback, 1); + + new_callback->ref_count = 1; + new_callback->func = func; + new_callback->data = data; + new_callback->notify = notify; + + g_source_set_callback_indirect (source, new_callback, &g_source_callback_funcs); +} + + +/** + * g_source_set_funcs: + * @source: a #GSource + * @funcs: the new #GSourceFuncs + * + * Sets the source functions (can be used to override + * default implementations) of an unattached source. + * + * Since: 2.12 + */ +void +g_source_set_funcs (GSource *source, + GSourceFuncs *funcs) +{ + g_return_if_fail (source != NULL); + g_return_if_fail (source->context == NULL); + g_return_if_fail (source->ref_count > 0); + g_return_if_fail (funcs != NULL); + + source->source_funcs = funcs; +} + +/** + * g_source_set_priority: + * @source: a #GSource + * @priority: the new priority. + * + * Sets the priority of a source. While the main loop is being + * run, a source will be dispatched if it is ready to be dispatched and no sources + * at a higher (numerically smaller) priority are ready to be dispatched. + **/ +void +g_source_set_priority (GSource *source, + gint priority) +{ + GSList *tmp_list; + GMainContext *context; + + g_return_if_fail (source != NULL); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + 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 plcae + */ + g_source_list_remove (source, source->context); + g_source_list_add (source, source->context); + + if (!SOURCE_BLOCKED (source)) + { + tmp_list = source->poll_fds; + while (tmp_list) + { + g_main_context_remove_poll_unlocked (context, tmp_list->data); + g_main_context_add_poll_unlocked (context, priority, tmp_list->data); + + tmp_list = tmp_list->next; + } + } + + UNLOCK_CONTEXT (source->context); + } +} + +/** + * g_source_get_priority: + * @source: a #GSource + * + * Gets the priority of a source. + * + * Return value: the priority of the source + **/ +gint +g_source_get_priority (GSource *source) +{ + g_return_val_if_fail (source != NULL, 0); + + return source->priority; +} + +/** + * g_source_set_can_recurse: + * @source: a #GSource + * @can_recurse: whether recursion is allowed for this source + * + * Sets whether a source can be called recursively. If @can_recurse is + * %TRUE, then while the source is being dispatched then this source + * will be processed normally. Otherwise, all processing of this + * source is blocked until the dispatch function returns. + **/ +void +g_source_set_can_recurse (GSource *source, + gboolean can_recurse) +{ + GMainContext *context; + + g_return_if_fail (source != NULL); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + if (can_recurse) + source->flags |= G_SOURCE_CAN_RECURSE; + else + source->flags &= ~G_SOURCE_CAN_RECURSE; + + if (context) + UNLOCK_CONTEXT (context); +} + +/** + * g_source_get_can_recurse: + * @source: a #GSource + * + * Checks whether a source is allowed to be called recursively. + * see g_source_set_can_recurse(). + * + * Return value: whether recursion is allowed. + **/ +gboolean +g_source_get_can_recurse (GSource *source) +{ + g_return_val_if_fail (source != NULL, FALSE); + + return (source->flags & G_SOURCE_CAN_RECURSE) != 0; +} + + +/** + * g_source_set_name: + * @source: a #GSource + * @name: debug name for the source + * + * Sets a name for the source, used in debugging and profiling. + * The name defaults to #NULL. + * + * The source name should describe in a human-readable way + * what the source does. For example, "X11 event queue" + * or "GTK+ repaint idle handler" or whatever it is. + * + * It is permitted to call this function multiple times, but is not + * recommended due to the potential performance impact. For example, + * one could change the name in the "check" function of a #GSourceFuncs + * to include details like the event type in the source name. + * + * Since: 2.26 + **/ +void +g_source_set_name (GSource *source, + const char *name) +{ + g_return_if_fail (source != NULL); + + /* setting back to NULL is allowed, just because it's + * weird if get_name can return NULL but you can't + * set that. + */ + + g_free (source->name); + source->name = g_strdup (name); +} + +/** + * g_source_get_name: + * @source: a #GSource + * + * Gets a name for the source, used in debugging and profiling. + * The name may be #NULL if it has never been set with + * g_source_set_name(). + * + * Return value: the name of the source + * Since: 2.26 + **/ +G_CONST_RETURN char* +g_source_get_name (GSource *source) +{ + g_return_val_if_fail (source != NULL, NULL); + + return source->name; +} + +/** + * g_source_set_name_by_id: + * @tag: a #GSource ID + * @name: debug name for the source + * + * Sets the name of a source using its ID. + * + * This is a convenience utility to set source names from the return + * value of g_idle_add(), g_timeout_add(), etc. + * + * Since: 2.26 + **/ +void +g_source_set_name_by_id (guint tag, + const char *name) +{ + GSource *source; + + g_return_if_fail (tag > 0); + + source = g_main_context_find_source_by_id (NULL, tag); + if (source == NULL) + return; + + g_source_set_name (source, name); +} + + +/** + * g_source_ref: + * @source: a #GSource + * + * Increases the reference count on a source by one. + * + * Return value: @source + **/ +GSource * +g_source_ref (GSource *source) +{ + GMainContext *context; + + g_return_val_if_fail (source != NULL, NULL); + + context = source->context; + + if (context) + LOCK_CONTEXT (context); + + source->ref_count++; + + if (context) + UNLOCK_CONTEXT (context); + + return source; +} + +/* g_source_unref() but possible to call within context lock + */ +static void +g_source_unref_internal (GSource *source, + GMainContext *context, + gboolean have_lock) +{ + gpointer old_cb_data = NULL; + GSourceCallbackFuncs *old_cb_funcs = NULL; + + g_return_if_fail (source != NULL); + + if (!have_lock && context) + LOCK_CONTEXT (context); + + source->ref_count--; + if (source->ref_count == 0) + { + old_cb_data = source->callback_data; + old_cb_funcs = source->callback_funcs; + + source->callback_data = NULL; + source->callback_funcs = NULL; + + if (context && !SOURCE_DESTROYED (source)) + { + g_warning (G_STRLOC ": ref_count == 0, but source is still attached to a context!"); + source->ref_count++; + } + else if (context) + g_source_list_remove (source, context); + + if (source->source_funcs->finalize) + source->source_funcs->finalize (source); + + g_free (source->name); + source->name = NULL; + + g_slist_free (source->poll_fds); + source->poll_fds = NULL; + g_free (source); + } + + if (!have_lock && context) + UNLOCK_CONTEXT (context); + + if (old_cb_funcs) + { + if (have_lock) + UNLOCK_CONTEXT (context); + + old_cb_funcs->unref (old_cb_data); + + if (have_lock) + LOCK_CONTEXT (context); + } +} + +/** + * g_source_unref: + * @source: a #GSource + * + * Decreases the reference count of a source by one. If the + * resulting reference count is zero the source and associated + * memory will be destroyed. + **/ +void +g_source_unref (GSource *source) +{ + g_return_if_fail (source != NULL); + + g_source_unref_internal (source, source->context, FALSE); +} + +/** + * g_main_context_find_source_by_id: + * @context: a #GMainContext (if %NULL, the default context will be used) + * @source_id: the source ID, as returned by g_source_get_id(). + * + * Finds a #GSource given a pair of context and ID. + * + * Return value: the #GSource if found, otherwise, %NULL + **/ +GSource * +g_main_context_find_source_by_id (GMainContext *context, + guint source_id) +{ + GSource *source; + + g_return_val_if_fail (source_id > 0, NULL); + + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + source = context->source_list; + while (source) + { + if (!SOURCE_DESTROYED (source) && + source->source_id == source_id) + break; + source = source->next; + } + + UNLOCK_CONTEXT (context); + + return source; +} + +/** + * g_main_context_find_source_by_funcs_user_data: + * @context: 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. + * + * Finds a source with the given source functions and user data. If + * 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 + **/ +GSource * +g_main_context_find_source_by_funcs_user_data (GMainContext *context, + GSourceFuncs *funcs, + gpointer user_data) +{ + GSource *source; + + g_return_val_if_fail (funcs != NULL, NULL); + + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + source = context->source_list; + while (source) + { + if (!SOURCE_DESTROYED (source) && + source->source_funcs == funcs && + source->callback_funcs) + { + GSourceFunc callback; + gpointer callback_data; + + source->callback_funcs->get (source->callback_data, source, &callback, &callback_data); + + if (callback_data == user_data) + break; + } + source = source->next; + } + + UNLOCK_CONTEXT (context); + + return source; +} + +/** + * g_main_context_find_source_by_user_data: + * @context: a #GMainContext + * @user_data: the user_data for the callback. + * + * Finds a source with the given user data for the callback. If + * 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 + **/ +GSource * +g_main_context_find_source_by_user_data (GMainContext *context, + gpointer user_data) +{ + GSource *source; + + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + source = context->source_list; + while (source) + { + if (!SOURCE_DESTROYED (source) && + source->callback_funcs) + { + GSourceFunc callback; + gpointer callback_data = NULL; + + source->callback_funcs->get (source->callback_data, source, &callback, &callback_data); + + if (callback_data == user_data) + break; + } + source = source->next; + } + + UNLOCK_CONTEXT (context); + + return source; +} + +/** + * g_source_remove: + * @tag: the ID of the source to remove. + * + * Removes the source with the given id from the default main context. + * The id of + * a #GSource is given by g_source_get_id(), or will be returned by the + * functions g_source_attach(), g_idle_add(), g_idle_add_full(), + * g_timeout_add(), g_timeout_add_full(), g_child_watch_add(), + * g_child_watch_add_full(), g_io_add_watch(), and g_io_add_watch_full(). + * + * See also g_source_destroy(). You must use g_source_destroy() for sources + * added to a non-default main context. + * + * Return value: %TRUE if the source was found and removed. + **/ +gboolean +g_source_remove (guint tag) +{ + GSource *source; + + g_return_val_if_fail (tag > 0, FALSE); + + source = g_main_context_find_source_by_id (NULL, tag); + if (source) + g_source_destroy (source); + + return source != NULL; +} + +/** + * g_source_remove_by_user_data: + * @user_data: the user_data for the callback. + * + * Removes a source from the default main loop context given the user + * data for the callback. If multiple sources exist with the same user + * data, only one will be destroyed. + * + * Return value: %TRUE if a source was found and removed. + **/ +gboolean +g_source_remove_by_user_data (gpointer user_data) +{ + GSource *source; + + source = g_main_context_find_source_by_user_data (NULL, user_data); + if (source) + { + g_source_destroy (source); + return TRUE; + } + else + return FALSE; +} + +/** + * g_source_remove_by_funcs_user_data: + * @funcs: The @source_funcs passed to g_source_new() + * @user_data: the user data for the callback + * + * Removes a source from the default main loop context given the + * source functions and user data. If multiple sources exist with the + * same source functions and user data, only one will be destroyed. + * + * Return value: %TRUE if a source was found and removed. + **/ +gboolean +g_source_remove_by_funcs_user_data (GSourceFuncs *funcs, + gpointer user_data) +{ + GSource *source; + + g_return_val_if_fail (funcs != NULL, FALSE); + + source = g_main_context_find_source_by_funcs_user_data (NULL, funcs, user_data); + if (source) + { + g_source_destroy (source); + return TRUE; + } + else + return FALSE; +} + +/** + * g_get_current_time: + * @result: #GTimeVal structure in which to store current time. + * + * Equivalent to the UNIX gettimeofday() function, but portable. + **/ +void +g_get_current_time (GTimeVal *result) +{ +#ifndef G_OS_WIN32 + struct timeval r; + + g_return_if_fail (result != NULL); + + /*this is required on alpha, there the timeval structs are int's + not longs and a cast only would fail horribly*/ + gettimeofday (&r, NULL); + result->tv_sec = r.tv_sec; + result->tv_usec = r.tv_usec; +#else + FILETIME ft; + guint64 time64; + + g_return_if_fail (result != NULL); + + GetSystemTimeAsFileTime (&ft); + memmove (&time64, &ft, sizeof (FILETIME)); + + /* Convert from 100s of nanoseconds since 1601-01-01 + * to Unix epoch. Yes, this is Y2038 unsafe. + */ + time64 -= G_GINT64_CONSTANT (116444736000000000); + time64 /= 10; + + result->tv_sec = time64 / 1000000; + result->tv_usec = time64 % 1000000; +#endif +} + +static void +g_main_dispatch_free (gpointer dispatch) +{ + g_slice_free (GMainDispatch, dispatch); +} + +/* Running the main loop */ + +static GMainDispatch * +get_dispatch (void) +{ + static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT; + GMainDispatch *dispatch = g_static_private_get (&depth_private); + if (!dispatch) + { + dispatch = g_slice_new0 (GMainDispatch); + g_static_private_set (&depth_private, dispatch, g_main_dispatch_free); + } + + return dispatch; +} + +/** + * g_main_depth: + * + * Returns the depth of the stack of calls to + * g_main_context_dispatch() on any #GMainContext in the current thread. + * That is, when called from the toplevel, it gives 0. When + * called from within a callback from g_main_context_iteration() + * (or g_main_loop_run(), etc.) it returns 1. When called from within + * a callback to a recursive call to g_main_context_iterate(), + * it returns 2. And so forth. + * + * This function is useful in a situation like the following: + * Imagine an extremely simple "garbage collected" system. + * + * |[ + * static GList *free_list; + * + * gpointer + * allocate_memory (gsize size) + * { + * gpointer result = g_malloc (size); + * free_list = g_list_prepend (free_list, result); + * return result; + * } + * + * void + * free_allocated_memory (void) + * { + * GList *l; + * for (l = free_list; l; l = l->next); + * g_free (l->data); + * g_list_free (free_list); + * free_list = NULL; + * } + * + * [...] + * + * while (TRUE); + * { + * g_main_context_iteration (NULL, TRUE); + * free_allocated_memory(); + * } + * ]| + * + * This works from an application, however, if you want to do the same + * thing from a library, it gets more difficult, since you no longer + * control the main loop. You might think you can simply use an idle + * function to make the call to free_allocated_memory(), but that + * doesn't work, since the idle function could be called from a + * recursive callback. This can be fixed by using g_main_depth() + * + * |[ + * gpointer + * allocate_memory (gsize size) + * { + * FreeListBlock *block = g_new (FreeListBlock, 1); + * block->mem = g_malloc (size); + * block->depth = g_main_depth (); + * free_list = g_list_prepend (free_list, block); + * return block->mem; + * } + * + * void + * free_allocated_memory (void) + * { + * GList *l; + * + * int depth = g_main_depth (); + * for (l = free_list; l; ); + * { + * GList *next = l->next; + * FreeListBlock *block = l->data; + * if (block->depth > depth) + * { + * g_free (block->mem); + * g_free (block); + * free_list = g_list_delete_link (free_list, l); + * } + * + * l = next; + * } + * } + * ]| + * + * There is a temptation to use g_main_depth() to solve + * problems with reentrancy. For instance, while waiting for data + * to be received from the network in response to a menu item, + * the menu item might be selected again. It might seem that + * one could make the menu item's callback return immediately + * and do nothing if g_main_depth() returns a value greater than 1. + * However, this should be avoided since the user then sees selecting + * the menu item do nothing. Furthermore, you'll find yourself adding + * these checks all over your code, since there are doubtless many, + * many things that the user could do. Instead, you can use the + * following techniques: + * + * <orderedlist> + * <listitem> + * <para> + * Use gtk_widget_set_sensitive() or modal dialogs to prevent + * the user from interacting with elements while the main + * loop is recursing. + * </para> + * </listitem> + * <listitem> + * <para> + * Avoid main loop recursion in situations where you can't handle + * arbitrary callbacks. Instead, structure your code so that you + * simply return to the main loop and then get called again when + * there is more work to do. + * </para> + * </listitem> + * </orderedlist> + * + * Return value: The main loop recursion level in the current thread + **/ +int +g_main_depth (void) +{ + GMainDispatch *dispatch = get_dispatch (); + return dispatch->depth; +} + +/** + * g_main_current_source: + * + * Returns the currently firing source for this thread. + * + * Return value: The currently firing source or %NULL. + * + * Since: 2.12 + */ +GSource * +g_main_current_source (void) +{ + GMainDispatch *dispatch = get_dispatch (); + return dispatch->dispatching_sources ? dispatch->dispatching_sources->data : NULL; +} + +/** + * g_source_is_destroyed: + * @source: a #GSource + * + * Returns whether @source has been destroyed. + * + * This is important when you operate upon your objects + * from within idle handlers, but may have freed the object + * before the dispatch of your idle handler. + * + * |[ + * static gboolean + * idle_callback (gpointer data) + * { + * SomeWidget *self = data; + * + * GDK_THREADS_ENTER (<!-- -->); + * /<!-- -->* do stuff with self *<!-- -->/ + * self->idle_id = 0; + * GDK_THREADS_LEAVE (<!-- -->); + * + * return FALSE; + * } + * + * static void + * some_widget_do_stuff_later (SomeWidget *self) + * { + * self->idle_id = g_idle_add (idle_callback, self); + * } + * + * static void + * some_widget_finalize (GObject *object) + * { + * SomeWidget *self = SOME_WIDGET (object); + * + * if (self->idle_id) + * g_source_remove (self->idle_id); + * + * G_OBJECT_CLASS (parent_class)->finalize (object); + * } + * ]| + * + * This will fail in a multi-threaded application if the + * widget is destroyed before the idle handler fires due + * to the use after free in the callback. A solution, to + * this particular problem, is to check to if the source + * has already been destroy within the callback. + * + * |[ + * static gboolean + * idle_callback (gpointer data) + * { + * SomeWidget *self = data; + * + * GDK_THREADS_ENTER (); + * if (!g_source_is_destroyed (g_main_current_source ())) + * { + * /<!-- -->* do stuff with self *<!-- -->/ + * } + * GDK_THREADS_LEAVE (); + * + * return FALSE; + * } + * ]| + * + * Return value: %TRUE if the source has been destroyed + * + * Since: 2.12 + */ +gboolean +g_source_is_destroyed (GSource *source) +{ + return SOURCE_DESTROYED (source); +} + +/* Temporarily remove all this source's file descriptors from the + * poll(), so that if data comes available for one of the file descriptors + * we don't continually spin in the poll() + */ +/* HOLDS: source->context's lock */ +static void +block_source (GSource *source) +{ + GSList *tmp_list; + + g_return_if_fail (!SOURCE_BLOCKED (source)); + + tmp_list = source->poll_fds; + while (tmp_list) + { + g_main_context_remove_poll_unlocked (source->context, tmp_list->data); + tmp_list = tmp_list->next; + } +} + +/* HOLDS: source->context's lock */ +static void +unblock_source (GSource *source) +{ + GSList *tmp_list; + + g_return_if_fail (!SOURCE_BLOCKED (source)); /* Source already unblocked */ + g_return_if_fail (!SOURCE_DESTROYED (source)); + + 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; + } +} + +/* HOLDS: context's lock */ +static void +g_main_dispatch (GMainContext *context) +{ + GMainDispatch *current = get_dispatch (); + guint i; + + for (i = 0; i < context->pending_dispatches->len; i++) + { + GSource *source = context->pending_dispatches->pdata[i]; + + context->pending_dispatches->pdata[i] = NULL; + g_assert (source); + + source->flags &= ~G_SOURCE_READY; + + if (!SOURCE_DESTROYED (source)) + { + gboolean was_in_call; + gpointer user_data = NULL; + GSourceFunc callback = NULL; + GSourceCallbackFuncs *cb_funcs; + gpointer cb_data; + gboolean need_destroy; + + gboolean (*dispatch) (GSource *, + GSourceFunc, + gpointer); + GSList current_source_link; + + dispatch = source->source_funcs->dispatch; + cb_funcs = source->callback_funcs; + cb_data = source->callback_data; + + if (cb_funcs) + cb_funcs->ref (cb_data); + + if ((source->flags & G_SOURCE_CAN_RECURSE) == 0) + block_source (source); + + was_in_call = source->flags & G_HOOK_FLAG_IN_CALL; + source->flags |= G_HOOK_FLAG_IN_CALL; + + if (cb_funcs) + cb_funcs->get (cb_data, source, &callback, &user_data); + + UNLOCK_CONTEXT (context); + + current->depth++; + /* The on-stack allocation of the GSList is unconventional, but + * we know that the lifetime of the link is bounded to this + * function as the link is kept in a thread specific list and + * not manipulated outside of this function and its descendants. + * Avoiding the overhead of a g_slist_alloc() is useful as many + * applications do little more than dispatch events. + * + * This is a performance hack - do not revert to g_slist_prepend()! + */ + current_source_link.data = source; + current_source_link.next = current->dispatching_sources; + current->dispatching_sources = ¤t_source_link; + need_destroy = ! dispatch (source, + callback, + user_data); + g_assert (current->dispatching_sources == ¤t_source_link); + current->dispatching_sources = current_source_link.next; + current->depth--; + + if (cb_funcs) + cb_funcs->unref (cb_data); + + LOCK_CONTEXT (context); + + if (!was_in_call) + source->flags &= ~G_HOOK_FLAG_IN_CALL; + + if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 && + !SOURCE_DESTROYED (source)) + unblock_source (source); + + /* Note: this depends on the fact that we can't switch + * sources from one main context to another + */ + if (need_destroy && !SOURCE_DESTROYED (source)) + { + g_assert (source->context == context); + g_source_destroy_internal (source, context, TRUE); + } + } + + SOURCE_UNREF (source, 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 + * + * Tries to become the owner of the specified context. + * If some other thread is the owner of the context, + * returns %FALSE immediately. Ownership is properly + * recursive: the owner can require ownership again + * and will release ownership when g_main_context_release() + * is called as many times as g_main_context_acquire(). + * + * You must be the owner of a context before you + * can call g_main_context_prepare(), g_main_context_query(), + * g_main_context_check(), g_main_context_dispatch(). + * + * Return value: %TRUE if the operation succeeded, and + * this thread is now the owner of @context. + **/ +gboolean +g_main_context_acquire (GMainContext *context) +{ +#ifdef G_THREADS_ENABLED + gboolean result = FALSE; + GThread *self = G_THREAD_SELF; + + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + if (!context->owner) + { + context->owner = self; + g_assert (context->owner_count == 0); + } + + if (context->owner == self) + { + context->owner_count++; + result = TRUE; + } + + UNLOCK_CONTEXT (context); + + return result; +#else /* !G_THREADS_ENABLED */ + return TRUE; +#endif /* G_THREADS_ENABLED */ +} + +/** + * g_main_context_release: + * @context: a #GMainContext + * + * Releases ownership of a context previously acquired by this thread + * with g_main_context_acquire(). If the context was acquired multiple + * times, the ownership will be released only when g_main_context_release() + * is called as many times as it was acquired. + **/ +void +g_main_context_release (GMainContext *context) +{ +#ifdef G_THREADS_ENABLED + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + context->owner_count--; + if (context->owner_count == 0) + { + context->owner = NULL; + + if (context->waiters) + { + GMainWaiter *waiter = context->waiters->data; + gboolean loop_internal_waiter = + (waiter->mutex == g_static_mutex_get_mutex (&context->mutex)); + context->waiters = g_slist_delete_link (context->waiters, + context->waiters); + if (!loop_internal_waiter) + g_mutex_lock (waiter->mutex); + + g_cond_signal (waiter->cond); + + if (!loop_internal_waiter) + g_mutex_unlock (waiter->mutex); + } + } + + UNLOCK_CONTEXT (context); +#endif /* G_THREADS_ENABLED */ +} + +/** + * g_main_context_wait: + * @context: a #GMainContext + * @cond: a condition variable + * @mutex: a mutex, currently held + * + * Tries to become the owner of the specified context, + * as with g_main_context_acquire(). But if another thread + * is the owner, atomically drop @mutex and wait on @cond until + * that owner releases ownership or until @cond is signaled, then + * try again (once) to become the owner. + * + * Return value: %TRUE if the operation succeeded, and + * this thread is now the owner of @context. + **/ +gboolean +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; + + if (context == NULL) + context = g_main_context_default (); + + loop_internal_waiter = (mutex == g_static_mutex_get_mutex (&context->mutex)); + + if (!loop_internal_waiter) + LOCK_CONTEXT (context); + + if (context->owner && context->owner != self) + { + GMainWaiter waiter; + + waiter.cond = cond; + waiter.mutex = mutex; + + context->waiters = g_slist_append (context->waiters, &waiter); + + if (!loop_internal_waiter) + UNLOCK_CONTEXT (context); + g_cond_wait (cond, mutex); + if (!loop_internal_waiter) + LOCK_CONTEXT (context); + + context->waiters = g_slist_remove (context->waiters, &waiter); + } + + if (!context->owner) + { + context->owner = self; + g_assert (context->owner_count == 0); + } + + if (context->owner == self) + { + context->owner_count++; + result = TRUE; + } + + if (!loop_internal_waiter) + UNLOCK_CONTEXT (context); + + return result; +#else /* !G_THREADS_ENABLED */ + return TRUE; +#endif /* G_THREADS_ENABLED */ +} + +/** + * g_main_context_prepare: + * @context: a #GMainContext + * @priority: location to store priority of highest priority + * source already ready. + * + * Prepares to poll sources within a main loop. The resulting information + * for polling is determined by calling g_main_context_query (). + * + * Return value: %TRUE if some source is ready to be dispatched + * prior to polling. + **/ +gboolean +g_main_context_prepare (GMainContext *context, + gint *priority) +{ + gint i; + gint n_ready = 0; + gint current_priority = G_MAXINT; + GSource *source; + + if (context == NULL) + context = g_main_context_default (); + + LOCK_CONTEXT (context); + + context->time_is_current = FALSE; + + if (context->in_check_or_prepare) + { + g_warning ("g_main_context_prepare() called recursively from within a source's check() or " + "prepare() member."); + UNLOCK_CONTEXT (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) + { + if (dispatch) + g_main_dispatch (context, ¤t_time); + + UNLOCK_CONTEXT (context); + return TRUE; + } +#endif + + /* If recursing, clear list of pending dispatches */ + + for (i = 0; i < context->pending_dispatches->len; i++) + { + if (context->pending_dispatches->pdata[i]) + SOURCE_UNREF ((GSource *)context->pending_dispatches->pdata[i], context); + } + g_ptr_array_set_size (context->pending_dispatches, 0); + + /* Prepare all sources */ + + context->timeout = -1; + + source = next_valid_source (context, NULL); + while (source) + { + gint source_timeout = -1; + + if ((n_ready > 0) && (source->priority > current_priority)) + { + SOURCE_UNREF (source, context); + break; + } + if (SOURCE_BLOCKED (source)) + goto next; + + if (!(source->flags & G_SOURCE_READY)) + { + gboolean result; + gboolean (*prepare) (GSource *source, + gint *timeout); + + prepare = source->source_funcs->prepare; + context->in_check_or_prepare++; + UNLOCK_CONTEXT (context); + + result = (*prepare) (source, &source_timeout); + + LOCK_CONTEXT (context); + context->in_check_or_prepare--; + + if (result) + source->flags |= G_SOURCE_READY; + } + + if (source->flags & G_SOURCE_READY) + { + n_ready++; + current_priority = source->priority; + context->timeout = 0; + } + + if (source_timeout >= 0) + { + if (context->timeout < 0) + context->timeout = source_timeout; + else + context->timeout = MIN (context->timeout, source_timeout); + } + + next: + source = next_valid_source (context, source); + } + + UNLOCK_CONTEXT (context); + + if (priority) + *priority = current_priority; + + return (n_ready > 0); +} + +/** + * 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. + * @n_fds: length of @fds. + * + * Determines information necessary to poll this main loop. + * + * Return value: the number of records actually stored in @fds, + * or, if more than @n_fds records need to be stored, the number + * of records that need to be stored. + **/ +gint +g_main_context_query (GMainContext *context, + gint max_priority, + gint *timeout, + GPollFD *fds, + gint n_fds) +{ + gint n_poll; + GPollRec *pollrec; + + LOCK_CONTEXT (context); + + pollrec = context->poll_records; + n_poll = 0; + while (pollrec && max_priority >= pollrec->priority) + { + /* We need to include entries with fd->events == 0 in the array because + * otherwise if the application changes fd->events behind our back and + * makes it non-zero, we'll be out of sync when we check the fds[] array. + * (Changing fd->events after adding an FD wasn't an anticipated use of + * this API, but it occurs in practice.) */ + if (n_poll < n_fds) + { + fds[n_poll].fd = pollrec->fd->fd; + /* In direct contradiction to the Unix98 spec, IRIX runs into + * difficulty if you pass in POLLERR, POLLHUP or POLLNVAL + * flags in the events field of the pollfd while it should + * just ignoring them. So we mask them out here. + */ + fds[n_poll].events = pollrec->fd->events & ~(G_IO_ERR|G_IO_HUP|G_IO_NVAL); + fds[n_poll].revents = 0; + } + + pollrec = pollrec->next; + n_poll++; + } + +#ifdef G_THREADS_ENABLED + context->poll_changed = FALSE; +#endif + + if (timeout) + { + *timeout = context->timeout; + if (*timeout != 0) + context->time_is_current = FALSE; + } + + UNLOCK_CONTEXT (context); + + return n_poll; +} + +/** + * 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() + * @n_fds: return value of g_main_context_query() + * + * Passes the results of polling back to the main loop. + * + * Return value: %TRUE if some sources are ready to be dispatched. + **/ +gboolean +g_main_context_check (GMainContext *context, + gint max_priority, + GPollFD *fds, + gint n_fds) +{ + GSource *source; + GPollRec *pollrec; + gint n_ready = 0; + gint i; + + LOCK_CONTEXT (context); + + if (context->in_check_or_prepare) + { + g_warning ("g_main_context_check() called recursively from within a source's check() or " + "prepare() member."); + UNLOCK_CONTEXT (context); + return FALSE; + } + +#ifdef G_THREADS_ENABLED + if (!context->poll_waiting) + { +#ifndef G_OS_WIN32 + gchar a; + read (context->wake_up_pipe[0], &a, 1); +#endif + } + else + context->poll_waiting = FALSE; + + /* If the set of poll file descriptors changed, bail out + * and let the main loop rerun + */ + if (context->poll_changed) + { + UNLOCK_CONTEXT (context); + return FALSE; + } +#endif /* G_THREADS_ENABLED */ + + pollrec = context->poll_records; + i = 0; + while (i < n_fds) + { + if (pollrec->fd->events) + pollrec->fd->revents = fds[i].revents; + + pollrec = pollrec->next; + i++; + } + + source = next_valid_source (context, NULL); + while (source) + { + if ((n_ready > 0) && (source->priority > max_priority)) + { + SOURCE_UNREF (source, context); + break; + } + if (SOURCE_BLOCKED (source)) + goto next; + + if (!(source->flags & G_SOURCE_READY)) + { + gboolean result; + gboolean (*check) (GSource *source); + + 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) + source->flags |= G_SOURCE_READY; + } + + if (source->flags & G_SOURCE_READY) + { + source->ref_count++; + g_ptr_array_add (context->pending_dispatches, source); + + n_ready++; + + /* never dispatch sources with less priority than the first + * one we choose to dispatch + */ + max_priority = source->priority; + } + + next: + source = next_valid_source (context, source); + } + + UNLOCK_CONTEXT (context); + + return n_ready > 0; +} + +/** + * g_main_context_dispatch: + * @context: a #GMainContext + * + * Dispatches all pending sources. + **/ +void +g_main_context_dispatch (GMainContext *context) +{ + LOCK_CONTEXT (context); + + if (context->pending_dispatches->len > 0) + { + g_main_dispatch (context); + } + + UNLOCK_CONTEXT (context); +} + +/* HOLDS context lock */ +static gboolean +g_main_context_iterate (GMainContext *context, + gboolean block, + gboolean dispatch, + GThread *self) +{ + gint max_priority; + gint timeout; + gboolean some_ready; + gint nfds, allocated_nfds; + GPollFD *fds = NULL; + + 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)); + + if (!got_ownership) + return FALSE; + } + else + LOCK_CONTEXT (context); +#endif /* G_THREADS_ENABLED */ + + if (!context->cached_poll_array) + { + context->cached_poll_array_size = context->n_poll_records; + context->cached_poll_array = g_new (GPollFD, context->n_poll_records); + } + + allocated_nfds = context->cached_poll_array_size; + fds = context->cached_poll_array; + + UNLOCK_CONTEXT (context); + + g_main_context_prepare (context, &max_priority); + + while ((nfds = g_main_context_query (context, max_priority, &timeout, fds, + allocated_nfds)) > allocated_nfds) + { + LOCK_CONTEXT (context); + g_free (fds); + context->cached_poll_array_size = allocated_nfds = nfds; + context->cached_poll_array = fds = g_new (GPollFD, nfds); + UNLOCK_CONTEXT (context); + } + + if (!block) + timeout = 0; + + g_main_context_poll (context, timeout, max_priority, fds, nfds); + + some_ready = g_main_context_check (context, max_priority, fds, nfds); + + if (dispatch) + g_main_context_dispatch (context); + +#ifdef G_THREADS_ENABLED + g_main_context_release (context); +#endif /* G_THREADS_ENABLED */ + + LOCK_CONTEXT (context); + + return some_ready; +} + +/** + * g_main_context_pending: + * @context: a #GMainContext (if %NULL, the default context will be used) + * + * Checks if any sources have pending events for the given context. + * + * Return value: %TRUE if events are pending. + **/ +gboolean +g_main_context_pending (GMainContext *context) +{ + gboolean retval; + + if (!context) + context = g_main_context_default(); + + LOCK_CONTEXT (context); + retval = g_main_context_iterate (context, FALSE, FALSE, G_THREAD_SELF); + UNLOCK_CONTEXT (context); + + return retval; +} + +/** + * g_main_context_iteration: + * @context: 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 + * 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 + * be interrupted for other reasons than an event source becoming ready. + * + * Return value: %TRUE if events were dispatched. + **/ +gboolean +g_main_context_iteration (GMainContext *context, gboolean may_block) +{ + gboolean retval; + + if (!context) + context = g_main_context_default(); + + LOCK_CONTEXT (context); + retval = g_main_context_iterate (context, may_block, TRUE, G_THREAD_SELF); + UNLOCK_CONTEXT (context); + + return retval; +} + +/** + * g_main_loop_new: + * @context: a #GMainContext (if %NULL, the default context will be used). + * @is_running: set to %TRUE to indicate that the loop is running. This + * is not very important since calling g_main_loop_run() will set this to + * %TRUE anyway. + * + * Creates a new #GMainLoop structure. + * + * Return value: a new #GMainLoop. + **/ +GMainLoop * +g_main_loop_new (GMainContext *context, + gboolean is_running) +{ + GMainLoop *loop; + + if (!context) + context = g_main_context_default(); + + g_main_context_ref (context); + + loop = g_new0 (GMainLoop, 1); + loop->context = context; + loop->is_running = is_running != FALSE; + loop->ref_count = 1; + + return loop; +} + +/** + * g_main_loop_ref: + * @loop: a #GMainLoop + * + * Increases the reference count on a #GMainLoop object by one. + * + * Return value: @loop + **/ +GMainLoop * +g_main_loop_ref (GMainLoop *loop) +{ + g_return_val_if_fail (loop != NULL, NULL); + g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL); + + g_atomic_int_inc (&loop->ref_count); + + return loop; +} + +/** + * g_main_loop_unref: + * @loop: a #GMainLoop + * + * Decreases the reference count on a #GMainLoop object by one. If + * the result is zero, free the loop and free all associated memory. + **/ +void +g_main_loop_unref (GMainLoop *loop) +{ + g_return_if_fail (loop != NULL); + g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0); + + if (!g_atomic_int_dec_and_test (&loop->ref_count)) + return; + + g_main_context_unref (loop->context); + g_free (loop); +} + +/** + * g_main_loop_run: + * @loop: a #GMainLoop + * + * Runs a main loop until g_main_loop_quit() is called on the loop. + * If this is called for the thread of the loop's #GMainContext, + * it will process events from the loop, otherwise it will + * simply wait. + **/ +void +g_main_loop_run (GMainLoop *loop) +{ + GThread *self = G_THREAD_SELF; + + 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); + + 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)); + + if (!loop->is_running) + { + UNLOCK_CONTEXT (loop->context); + if (got_ownership) + g_main_context_release (loop->context); + g_main_loop_unref (loop); + return; + } + + g_assert (got_ownership); + } + else + LOCK_CONTEXT (loop->context); +#endif /* G_THREADS_ENABLED */ + + if (loop->context->in_check_or_prepare) + { + g_warning ("g_main_loop_run(): called recursively from within a source's " + "check() or prepare() member, iteration not possible."); + return; + } + + g_atomic_int_inc (&loop->ref_count); + loop->is_running = TRUE; + while (loop->is_running) + g_main_context_iterate (loop->context, TRUE, TRUE, self); + + UNLOCK_CONTEXT (loop->context); + +#ifdef G_THREADS_ENABLED + g_main_context_release (loop->context); +#endif /* G_THREADS_ENABLED */ + + g_main_loop_unref (loop); +} + +/** + * g_main_loop_quit: + * @loop: a #GMainLoop + * + * Stops a #GMainLoop from running. Any calls to g_main_loop_run() + * for the loop will return. + * + * Note that sources that have already been dispatched when + * g_main_loop_quit() is called will still be executed. + **/ +void +g_main_loop_quit (GMainLoop *loop) +{ + g_return_if_fail (loop != NULL); + g_return_if_fail (g_atomic_int_get (&loop->ref_count) > 0); + + LOCK_CONTEXT (loop->context); + loop->is_running = FALSE; + g_main_context_wakeup_unlocked (loop->context); + +#ifdef G_THREADS_ENABLED + if (loop->context->cond) + g_cond_broadcast (loop->context->cond); +#endif /* G_THREADS_ENABLED */ + + UNLOCK_CONTEXT (loop->context); +} + +/** + * g_main_loop_is_running: + * @loop: a #GMainLoop. + * + * Checks to see if the main loop is currently being run via g_main_loop_run(). + * + * Return value: %TRUE if the mainloop is currently being run. + **/ +gboolean +g_main_loop_is_running (GMainLoop *loop) +{ + g_return_val_if_fail (loop != NULL, FALSE); + g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, FALSE); + + return loop->is_running; +} + +/** + * g_main_loop_get_context: + * @loop: a #GMainLoop. + * + * Returns the #GMainContext of @loop. + * + * Return value: the #GMainContext of @loop + **/ +GMainContext * +g_main_loop_get_context (GMainLoop *loop) +{ + g_return_val_if_fail (loop != NULL, NULL); + g_return_val_if_fail (g_atomic_int_get (&loop->ref_count) > 0, NULL); + + return loop->context; +} + +/* HOLDS: context's lock */ +static void +g_main_context_poll (GMainContext *context, + gint timeout, + gint priority, + GPollFD *fds, + gint n_fds) +{ +#ifdef G_MAIN_POLL_DEBUG + GTimer *poll_timer; + GPollRec *pollrec; + gint i; +#endif + + GPollFunc poll_func; + + if (n_fds || timeout != 0) + { +#ifdef G_MAIN_POLL_DEBUG + if (_g_main_poll_debug) + { + g_print ("polling context=%p n=%d timeout=%d\n", + context, n_fds, timeout); + poll_timer = g_timer_new (); + } +#endif + + LOCK_CONTEXT (context); + + poll_func = context->poll_func; + + UNLOCK_CONTEXT (context); + if ((*poll_func) (fds, n_fds, timeout) < 0 && errno != EINTR) + { +#ifndef G_OS_WIN32 + g_warning ("poll(2) failed due to: %s.", + g_strerror (errno)); +#else + /* If g_poll () returns -1, it has already called g_warning() */ +#endif + } + +#ifdef G_MAIN_POLL_DEBUG + if (_g_main_poll_debug) + { + LOCK_CONTEXT (context); + + g_print ("g_main_poll(%d) timeout: %d - elapsed %12.10f seconds", + n_fds, + timeout, + g_timer_elapsed (poll_timer, NULL)); + g_timer_destroy (poll_timer); + pollrec = context->poll_records; + + while (pollrec != NULL) + { + i = 0; + while (i < n_fds) + { + if (fds[i].fd == pollrec->fd->fd && + pollrec->fd->events && + fds[i].revents) + { + g_print (" [" G_POLLFD_FORMAT " :", fds[i].fd); + if (fds[i].revents & G_IO_IN) + g_print ("i"); + if (fds[i].revents & G_IO_OUT) + g_print ("o"); + if (fds[i].revents & G_IO_PRI) + g_print ("p"); + if (fds[i].revents & G_IO_ERR) + g_print ("e"); + if (fds[i].revents & G_IO_HUP) + g_print ("h"); + if (fds[i].revents & G_IO_NVAL) + g_print ("n"); + g_print ("]"); + } + i++; + } + pollrec = pollrec->next; + } + g_print ("\n"); + + UNLOCK_CONTEXT (context); + } +#endif + } /* if (n_fds || timeout != 0) */ +} + +/** + * g_main_context_add_poll: + * @context: 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 seldomly be used directly. Instead + * a typical event source will use g_source_add_poll() instead. + **/ +void +g_main_context_add_poll (GMainContext *context, + GPollFD *fd, + gint priority) +{ + if (!context) + context = g_main_context_default (); + + g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); + g_return_if_fail (fd); + + LOCK_CONTEXT (context); + g_main_context_add_poll_unlocked (context, priority, fd); + UNLOCK_CONTEXT (context); +} + +/* HOLDS: main_loop_lock */ +static void +g_main_context_add_poll_unlocked (GMainContext *context, + gint priority, + GPollFD *fd) +{ + GPollRec *lastrec, *pollrec; + GPollRec *newrec = g_slice_new (GPollRec); + + /* This file descriptor may be checked before we ever poll */ + fd->revents = 0; + newrec->fd = fd; + newrec->priority = priority; + + lastrec = NULL; + pollrec = context->poll_records; + while (pollrec && priority >= pollrec->priority) + { + lastrec = pollrec; + pollrec = pollrec->next; + } + + if (lastrec) + lastrec->next = newrec; + else + context->poll_records = newrec; + + newrec->next = pollrec; + + 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_main_context_remove_poll: + * @context:a #GMainContext + * @fd: a #GPollFD descriptor previously added with g_main_context_add_poll() + * + * Removes file descriptor from the set of file descriptors to be + * polled for a particular context. + **/ +void +g_main_context_remove_poll (GMainContext *context, + GPollFD *fd) +{ + if (!context) + context = g_main_context_default (); + + g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); + g_return_if_fail (fd); + + LOCK_CONTEXT (context); + g_main_context_remove_poll_unlocked (context, fd); + UNLOCK_CONTEXT (context); +} + +static void +g_main_context_remove_poll_unlocked (GMainContext *context, + GPollFD *fd) +{ + GPollRec *pollrec, *lastrec; + + lastrec = NULL; + pollrec = context->poll_records; + + while (pollrec) + { + if (pollrec->fd == fd) + { + if (lastrec != NULL) + lastrec->next = pollrec->next; + else + context->poll_records = pollrec->next; + + g_slice_free (GPollRec, pollrec); + + context->n_poll_records--; + break; + } + lastrec = pollrec; + pollrec = pollrec->next; + } + +#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_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. + **/ +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->time_is_current) + { + g_get_current_time (&context->current_time); + context->time_is_current = TRUE; + } + + *timeval = context->current_time; + + UNLOCK_CONTEXT (context); +} + +/** + * g_main_context_set_poll_func: + * @context: a #GMainContext + * @func: the function to call to poll all file descriptors + * + * Sets the function to use to handle polling of file descriptors. It + * will be used instead of the poll() system call + * (or GLib's replacement function, which is used where + * poll() isn't available). + * + * This function could possibly be used to integrate the GLib event + * loop with an external event loop. + **/ +void +g_main_context_set_poll_func (GMainContext *context, + GPollFunc func) +{ + if (!context) + context = g_main_context_default (); + + g_return_if_fail (g_atomic_int_get (&context->ref_count) > 0); + + LOCK_CONTEXT (context); + + if (func) + context->poll_func = func; + else + context->poll_func = g_poll; + + UNLOCK_CONTEXT (context); +} + +/** + * g_main_context_get_poll_func: + * @context: a #GMainContext + * + * Gets the poll function set by g_main_context_set_poll_func(). + * + * Return value: the poll function + **/ +GPollFunc +g_main_context_get_poll_func (GMainContext *context) +{ + GPollFunc result; + + if (!context) + context = g_main_context_default (); + + g_return_val_if_fail (g_atomic_int_get (&context->ref_count) > 0, NULL); + + LOCK_CONTEXT (context); + result = context->poll_func; + UNLOCK_CONTEXT (context); + + return result; +} + +/* 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; +#ifndef G_OS_WIN32 + write (context->wake_up_pipe[1], "A", 1); +#else + ReleaseSemaphore (context->wake_up_semaphore, 1, NULL); +#endif + } +#endif +} + +/** + * g_main_context_wakeup: + * @context: a #GMainContext + * + * If @context is currently waiting in a poll(), interrupt + * the poll(), and continue the iteration process. + **/ +void +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_main_context_is_owner: + * @context: a #GMainContext + * + * Determines whether this thread holds the (recursive) + * ownership of this #GMaincontext. This is useful to + * know before waiting on another thread that may be + * blocking to get ownership of @context. + * + * Returns: %TRUE if current thread is owner of @context. + * + * Since: 2.10 + **/ +gboolean +g_main_context_is_owner (GMainContext *context) +{ + gboolean is_owner; + + 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; +} + +/* Timeouts */ + +static void +g_timeout_set_expiration (GTimeoutSource *timeout_source, + GTimeVal *current_time) +{ + guint seconds = timeout_source->interval / 1000; + guint msecs = timeout_source->interval - seconds * 1000; + + timeout_source->expiration.tv_sec = current_time->tv_sec + seconds; + timeout_source->expiration.tv_usec = current_time->tv_usec + msecs * 1000; + if (timeout_source->expiration.tv_usec >= 1000000) + { + timeout_source->expiration.tv_usec -= 1000000; + timeout_source->expiration.tv_sec++; + } + if (timer_perturb==-1) + { + /* + * we want a per machine/session unique 'random' value; try the dbus + * address first, that has a UUID in it. If there is no dbus, use the + * hostname for hashing. + */ + const char *session_bus_address = g_getenv ("DBUS_SESSION_BUS_ADDRESS"); + if (!session_bus_address) + session_bus_address = g_getenv ("HOSTNAME"); + if (session_bus_address) + timer_perturb = ABS ((gint) g_str_hash (session_bus_address)); + else + timer_perturb = 0; + } + if (timeout_source->granularity) + { + gint remainder; + gint gran; /* in usecs */ + gint perturb; + + gran = timeout_source->granularity * 1000; + perturb = timer_perturb % gran; + /* + * We want to give each machine a per machine pertubation; + * shift time back first, and forward later after the rounding + */ + + timeout_source->expiration.tv_usec -= perturb; + if (timeout_source->expiration.tv_usec < 0) + { + timeout_source->expiration.tv_usec += 1000000; + timeout_source->expiration.tv_sec--; + } + + remainder = timeout_source->expiration.tv_usec % gran; + if (remainder >= gran/4) /* round up */ + timeout_source->expiration.tv_usec += gran; + timeout_source->expiration.tv_usec -= remainder; + /* shift back */ + timeout_source->expiration.tv_usec += perturb; + + /* the rounding may have overflown tv_usec */ + while (timeout_source->expiration.tv_usec > 1000000) + { + timeout_source->expiration.tv_usec -= 1000000; + timeout_source->expiration.tv_sec++; + } + } +} + +static gboolean +g_timeout_prepare (GSource *source, + gint *timeout) +{ + glong sec; + glong msec; + GTimeVal current_time; + + GTimeoutSource *timeout_source = (GTimeoutSource *)source; + + g_source_get_current_time (source, ¤t_time); + + sec = timeout_source->expiration.tv_sec - current_time.tv_sec; + msec = (timeout_source->expiration.tv_usec - current_time.tv_usec) / 1000; + + /* We do the following in a rather convoluted fashion to deal with + * the fact that we don't have an integral type big enough to hold + * the difference of two timevals in millseconds. + */ + if (sec < 0 || (sec == 0 && msec < 0)) + msec = 0; + else + { + glong interval_sec = timeout_source->interval / 1000; + glong interval_msec = timeout_source->interval % 1000; + + if (msec < 0) + { + msec += 1000; + sec -= 1; + } + + if (sec > interval_sec || + (sec == interval_sec && msec > interval_msec)) + { + /* The system time has been set backwards, so we + * reset the expiration time to now + timeout_source->interval; + * this at least avoids hanging for long periods of time. + */ + g_timeout_set_expiration (timeout_source, ¤t_time); + msec = MIN (G_MAXINT, timeout_source->interval); + } + else + { + msec = MIN (G_MAXINT, (guint)msec + 1000 * (guint)sec); + } + } + + *timeout = (gint)msec; + + return msec == 0; +} + +static gboolean +g_timeout_check (GSource *source) +{ + GTimeVal current_time; + GTimeoutSource *timeout_source = (GTimeoutSource *)source; + + g_source_get_current_time (source, ¤t_time); + + return ((timeout_source->expiration.tv_sec < current_time.tv_sec) || + ((timeout_source->expiration.tv_sec == current_time.tv_sec) && + (timeout_source->expiration.tv_usec <= current_time.tv_usec))); +} + +static gboolean +g_timeout_dispatch (GSource *source, + GSourceFunc callback, + gpointer user_data) +{ + GTimeoutSource *timeout_source = (GTimeoutSource *)source; + + if (!callback) + { + g_warning ("Timeout source dispatched without callback\n" + "You must call g_source_set_callback()."); + return FALSE; + } + + if (callback (user_data)) + { + GTimeVal current_time; + + g_source_get_current_time (source, ¤t_time); + g_timeout_set_expiration (timeout_source, ¤t_time); + + return TRUE; + } + else + return FALSE; +} + +/** + * g_timeout_source_new: + * @interval: the timeout interval in milliseconds. + * + * Creates a new timeout source. + * + * The source will not initially be associated with any #GMainContext + * and must be added to one with g_source_attach() before it will be + * executed. + * + * Return value: the newly-created timeout source + **/ +GSource * +g_timeout_source_new (guint interval) +{ + GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource)); + GTimeoutSource *timeout_source = (GTimeoutSource *)source; + GTimeVal current_time; + + timeout_source->interval = interval; + + g_get_current_time (¤t_time); + g_timeout_set_expiration (timeout_source, ¤t_time); + + return source; +} + +/** + * g_timeout_source_new_seconds: + * @interval: the timeout interval in seconds + * + * Creates a new timeout source. + * + * The source will not initially be associated with any #GMainContext + * and must be added to one with g_source_attach() before it will be + * executed. + * + * The scheduling granularity/accuracy of this timeout source will be + * in seconds. + * + * Return value: the newly-created timeout source + * + * Since: 2.14 + **/ +GSource * +g_timeout_source_new_seconds (guint interval) +{ + GSource *source = g_source_new (&g_timeout_funcs, sizeof (GTimeoutSource)); + GTimeoutSource *timeout_source = (GTimeoutSource *)source; + GTimeVal current_time; + + timeout_source->interval = 1000*interval; + timeout_source->granularity = 1000; + + g_get_current_time (¤t_time); + g_timeout_set_expiration (timeout_source, ¤t_time); + + return source; +} + + +/** + * g_timeout_add_full: + * @priority: the priority of the timeout source. Typically this will be in + * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH. + * @interval: the time between calls to the function, in milliseconds + * (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 + * + * Sets a function to be called at regular intervals, with the given + * priority. The function is called repeatedly until it returns + * %FALSE, at which point the timeout is automatically destroyed and + * the function will not be called again. The @notify function is + * called when the timeout is destroyed. The first call to the + * function will be at the end of the first @interval. + * + * Note that timeout functions may be delayed, due to the processing of other + * event sources. Thus they should not be relied on for precise timing. + * After each call to the timeout function, the time of the next + * timeout is recalculated based on the current time and the given interval + * (it does not try to 'catch up' time lost in delays). + * + * This internally creates a main loop source using g_timeout_source_new() + * and attaches it to the main loop context using g_source_attach(). You can + * do these steps manually if you need greater control. + * + * Return value: the ID (greater than 0) of the event source. + **/ +guint +g_timeout_add_full (gint priority, + guint interval, + GSourceFunc function, + gpointer data, + GDestroyNotify notify) +{ + GSource *source; + guint id; + + g_return_val_if_fail (function != NULL, 0); + + source = g_timeout_source_new (interval); + + if (priority != G_PRIORITY_DEFAULT) + g_source_set_priority (source, priority); + + g_source_set_callback (source, function, data, notify); + id = g_source_attach (source, NULL); + g_source_unref (source); + + return id; +} + +/** + * g_timeout_add: + * @interval: the time between calls to the function, in milliseconds + * (1/1000ths of a second) + * @function: function to call + * @data: data to pass to @function + * + * Sets a function to be called at regular intervals, with the default + * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly + * until it returns %FALSE, at which point the timeout is automatically + * destroyed and the function will not be called again. The first call + * to the function will be at the end of the first @interval. + * + * Note that timeout functions may be delayed, due to the processing of other + * event sources. Thus they should not be relied on for precise timing. + * After each call to the timeout function, the time of the next + * timeout is recalculated based on the current time and the given interval + * (it does not try to 'catch up' time lost in delays). + * + * If you want to have a timer in the "seconds" range and do not care + * about the exact time of the first call of the timer, use the + * g_timeout_add_seconds() function; this function allows for more + * optimizations and more efficient system power usage. + * + * This internally creates a main loop source using g_timeout_source_new() + * and attaches it to the main loop context using g_source_attach(). You can + * do these steps manually if you need greater control. + * + * Return value: the ID (greater than 0) of the event source. + **/ +guint +g_timeout_add (guint32 interval, + GSourceFunc function, + gpointer data) +{ + return g_timeout_add_full (G_PRIORITY_DEFAULT, + interval, function, data, NULL); +} + +/** + * g_timeout_add_seconds_full: + * @priority: the priority of the timeout source. Typically this will be in + * the range between #G_PRIORITY_DEFAULT and #G_PRIORITY_HIGH. + * @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 + * + * Sets a function to be called at regular intervals, with @priority. + * The function is called repeatedly until it returns %FALSE, at which + * point the timeout is automatically destroyed and the function will + * not be called again. + * + * Unlike g_timeout_add(), this function operates at whole second granularity. + * The initial starting point of the timer is determined by the implementation + * and the implementation is expected to group multiple timers together so that + * they fire all at the same time. + * To allow this grouping, the @interval to the first timer is rounded + * and can deviate up to one second from the specified interval. + * Subsequent timer iterations will generally run at the specified interval. + * + * Note that timeout functions may be delayed, due to the processing of other + * event sources. Thus they should not be relied on for precise timing. + * After each call to the timeout function, the time of the next + * timeout is recalculated based on the current time and the given @interval + * + * If you want timing more precise than whole seconds, use g_timeout_add() + * instead. + * + * The grouping of timers to fire at the same time results in a more power + * and CPU efficient behavior so if your timer is in multiples of seconds + * and you don't require the first timer exactly one second from now, the + * use of g_timeout_add_seconds() is preferred over g_timeout_add(). + * + * This internally creates a main loop source using + * g_timeout_source_new_seconds() and attaches it to the main loop context + * using g_source_attach(). You can do these steps manually if you need + * greater control. + * + * Return value: the ID (greater than 0) of the event source. + * + * Since: 2.14 + **/ +guint +g_timeout_add_seconds_full (gint priority, + guint32 interval, + GSourceFunc function, + gpointer data, + GDestroyNotify notify) +{ + GSource *source; + guint id; + + g_return_val_if_fail (function != NULL, 0); + + source = g_timeout_source_new_seconds (interval); + + if (priority != G_PRIORITY_DEFAULT) + g_source_set_priority (source, priority); + + g_source_set_callback (source, function, data, notify); + id = g_source_attach (source, NULL); + g_source_unref (source); + + return id; +} + +/** + * g_timeout_add_seconds: + * @interval: the time between calls to the function, in seconds + * @function: function to call + * @data: data to pass to @function + * + * Sets a function to be called at regular intervals with the default + * priority, #G_PRIORITY_DEFAULT. The function is called repeatedly until + * it returns %FALSE, at which point the timeout is automatically destroyed + * and the function will not be called again. + * + * This internally creates a main loop source using + * g_timeout_source_new_seconds() and attaches it to the main loop context + * using g_source_attach(). You can do these steps manually if you need + * greater control. Also see g_timout_add_seconds_full(). + * + * Return value: the ID (greater than 0) of the event source. + * + * Since: 2.14 + **/ +guint +g_timeout_add_seconds (guint interval, + GSourceFunc function, + gpointer data) +{ + g_return_val_if_fail (function != NULL, 0); + + return g_timeout_add_seconds_full (G_PRIORITY_DEFAULT, interval, function, data, NULL); +} + +/* Child watch functions */ + +#ifdef G_OS_WIN32 + +static gboolean +g_child_watch_prepare (GSource *source, + gint *timeout) +{ + *timeout = -1; + return FALSE; +} + + +static gboolean +g_child_watch_check (GSource *source) +{ + GChildWatchSource *child_watch_source; + gboolean child_exited; + + child_watch_source = (GChildWatchSource *) source; + + child_exited = child_watch_source->poll.revents & G_IO_IN; + + if (child_exited) + { + DWORD child_status; + + /* + * Note: We do _not_ check for the special value of STILL_ACTIVE + * since we know that the process has exited and doing so runs into + * problems if the child process "happens to return STILL_ACTIVE(259)" + * as Microsoft's Platform SDK puts it. + */ + if (!GetExitCodeProcess (child_watch_source->pid, &child_status)) + { + gchar *emsg = g_win32_error_message (GetLastError ()); + g_warning (G_STRLOC ": GetExitCodeProcess() failed: %s", emsg); + g_free (emsg); + + child_watch_source->child_status = -1; + } + else + child_watch_source->child_status = child_status; + } + + return child_exited; +} + +#else /* G_OS_WIN32 */ + +static gboolean +check_for_child_exited (GSource *source) +{ + GChildWatchSource *child_watch_source; + gint count; + + /* protect against another SIGCHLD in the middle of this call */ + count = child_watch_count; + + child_watch_source = (GChildWatchSource *) source; + + if (child_watch_source->child_exited) + return TRUE; + + if (child_watch_source->count < count) + { + gint child_status; + + 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; + } + + return child_watch_source->child_exited; +} + +static gboolean +g_child_watch_prepare (GSource *source, + gint *timeout) +{ + *timeout = -1; + + return check_for_child_exited (source); +} + + +static gboolean +g_child_watch_check (GSource *source) +{ + return check_for_child_exited (source); +} + +#endif /* G_OS_WIN32 */ + +static gboolean +g_child_watch_dispatch (GSource *source, + GSourceFunc callback, + gpointer user_data) +{ + GChildWatchSource *child_watch_source; + GChildWatchFunc child_watch_callback = (GChildWatchFunc) callback; + + child_watch_source = (GChildWatchSource *) source; + + if (!callback) + { + g_warning ("Child watch source dispatched without callback\n" + "You must call g_source_set_callback()."); + return FALSE; + } + + (child_watch_callback) (child_watch_source->pid, child_watch_source->child_status, user_data); + + /* We never keep a child watch source around as the child is gone */ + return FALSE; +} + +#ifndef G_OS_WIN32 + +static void +g_child_watch_signal_handler (int signum) +{ + child_watch_count ++; + + if (child_watch_init_state == CHILD_WATCH_INITIALIZED_THREADED) + { + write (child_watch_wake_up_pipe[1], "B", 1); + } + else + { + /* We count on the signal interrupting the poll in the same thread. + */ + } +} + +static void +g_child_watch_source_init_single (void) +{ + struct sigaction action; + + g_assert (! g_thread_supported()); + g_assert (child_watch_init_state == CHILD_WATCH_UNINITIALIZED); + + child_watch_init_state = CHILD_WATCH_INITIALIZED_SINGLE; + + action.sa_handler = g_child_watch_signal_handler; + sigemptyset (&action.sa_mask); + action.sa_flags = SA_NOCLDSTOP; + sigaction (SIGCHLD, &action, NULL); +} + +G_GNUC_NORETURN static gpointer +child_watch_helper_thread (gpointer data) +{ + while (1) + { + gchar b[20]; + GSList *list; + + read (child_watch_wake_up_pipe[0], b, 20); + + /* 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; + + context = list->data; + if (g_atomic_int_get (&context->ref_count) > 0) + /* Due to racing conditions we can find ref_count == 0, in + * that case, however, the context is still not destroyed + * and no poll can be active, otherwise the ref_count + * wouldn't be 0 */ + g_main_context_wakeup (context); + } + G_UNLOCK (main_context_list); + } +} + +static void +g_child_watch_source_init_multi_threaded (void) +{ + GError *error = NULL; + struct sigaction action; + + g_assert (g_thread_supported()); + + if (pipe (child_watch_wake_up_pipe) < 0) + g_error ("Cannot create wake up pipe: %s\n", g_strerror (errno)); + fcntl (child_watch_wake_up_pipe[1], F_SETFL, O_NONBLOCK | fcntl (child_watch_wake_up_pipe[1], F_GETFL)); + + /* We create a helper thread that polls on the wakeup pipe indefinitely */ + /* FIXME: Think this through for races */ + if (g_thread_create (child_watch_helper_thread, NULL, FALSE, &error) == NULL) + g_error ("Cannot create a thread to monitor child exit status: %s\n", error->message); + child_watch_init_state = CHILD_WATCH_INITIALIZED_THREADED; + + action.sa_handler = g_child_watch_signal_handler; + sigemptyset (&action.sa_mask); + action.sa_flags = SA_RESTART | SA_NOCLDSTOP; + sigaction (SIGCHLD, &action, NULL); +} + +static void +g_child_watch_source_init_promote_single_to_threaded (void) +{ + g_child_watch_source_init_multi_threaded (); +} + +static void +g_child_watch_source_init (void) +{ + if (g_thread_supported()) + { + if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED) + g_child_watch_source_init_multi_threaded (); + else if (child_watch_init_state == CHILD_WATCH_INITIALIZED_SINGLE) + g_child_watch_source_init_promote_single_to_threaded (); + } + else + { + if (child_watch_init_state == CHILD_WATCH_UNINITIALIZED) + g_child_watch_source_init_single (); + } +} + +#endif /* !G_OS_WIN32 */ + +/** + * g_child_watch_source_new: + * @pid: process to watch. On POSIX the pid of a child process. On + * Windows a handle for a process (which doesn't have to be a child). + * + * Creates a new child_watch source. + * + * The source will not initially be associated with any #GMainContext + * and must be added to one with g_source_attach() before it will be + * executed. + * + * Note that child watch sources can only be used in conjunction with + * <literal>g_spawn...</literal> when the %G_SPAWN_DO_NOT_REAP_CHILD + * flag is used. + * + * Note that on platforms where #GPid must be explicitly closed + * (see g_spawn_close_pid()) @pid must not be closed while the + * source is still active. Typically, you will want to call + * g_spawn_close_pid() in the callback function for the source. + * + * Note further that using g_child_watch_source_new() is not + * compatible with calling <literal>waitpid(-1)</literal> in + * the application. Calling waitpid() for individual pids will + * still work fine. + * + * Return value: the newly-created child watch source + * + * Since: 2.4 + **/ +GSource * +g_child_watch_source_new (GPid pid) +{ + GSource *source = g_source_new (&g_child_watch_funcs, sizeof (GChildWatchSource)); + GChildWatchSource *child_watch_source = (GChildWatchSource *)source; + +#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 (); +#endif /* G_OS_WIN32 */ + + child_watch_source->pid = pid; + + return source; +} + +/** + * g_child_watch_add_full: + * @priority: the priority of the idle source. Typically this will be in the + * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE. + * @pid: process to watch. On POSIX the pid of a child process. On + * 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 + * + * Sets a function to be called when the child indicated by @pid + * exits, at the priority @priority. + * + * If you obtain @pid from g_spawn_async() or g_spawn_async_with_pipes() + * you will need to pass #G_SPAWN_DO_NOT_REAP_CHILD as flag to + * the spawn function for the child watching to work. + * + * 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. + * + * GLib supports only a single callback per process id. + * + * This internally creates a main loop source using + * g_child_watch_source_new() and attaches it to the main loop context + * using g_source_attach(). You can do these steps manually if you + * need greater control. + * + * Return value: the ID (greater than 0) of the event source. + * + * Since: 2.4 + **/ +guint +g_child_watch_add_full (gint priority, + GPid pid, + GChildWatchFunc function, + gpointer data, + GDestroyNotify notify) +{ + GSource *source; + guint id; + + g_return_val_if_fail (function != NULL, 0); + + source = g_child_watch_source_new (pid); + + if (priority != G_PRIORITY_DEFAULT) + g_source_set_priority (source, priority); + + g_source_set_callback (source, (GSourceFunc) function, data, notify); + id = g_source_attach (source, NULL); + g_source_unref (source); + + return id; +} + +/** + * g_child_watch_add: + * @pid: process id to watch. On POSIX the pid of a child process. On + * Windows a handle for a process (which doesn't have to be a child). + * @function: function to call + * @data: data to pass to @function + * + * Sets a function to be called when the child indicated by @pid + * exits, at a default priority, #G_PRIORITY_DEFAULT. + * + * 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. + * + * 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. + * + * GLib supports only a single callback per process id. + * + * This internally creates a main loop source using + * g_child_watch_source_new() and attaches it to the main loop context + * using g_source_attach(). You can do these steps manually if you + * need greater control. + * + * Return value: the ID (greater than 0) of the event source. + * + * Since: 2.4 + **/ +guint +g_child_watch_add (GPid pid, + GChildWatchFunc function, + gpointer data) +{ + return g_child_watch_add_full (G_PRIORITY_DEFAULT, pid, function, data, NULL); +} + + +/* Idle functions */ + +static gboolean +g_idle_prepare (GSource *source, + gint *timeout) +{ + *timeout = 0; + + return TRUE; +} + +static gboolean +g_idle_check (GSource *source) +{ + return TRUE; +} + +static gboolean +g_idle_dispatch (GSource *source, + GSourceFunc callback, + gpointer user_data) +{ + if (!callback) + { + g_warning ("Idle source dispatched without callback\n" + "You must call g_source_set_callback()."); + return FALSE; + } + + return callback (user_data); +} + +/** + * g_idle_source_new: + * + * Creates a new idle source. + * + * The source will not initially be associated with any #GMainContext + * and must be added to one with g_source_attach() before it will be + * executed. Note that the default priority for idle sources is + * %G_PRIORITY_DEFAULT_IDLE, as compared to other sources which + * have a default priority of %G_PRIORITY_DEFAULT. + * + * Return value: the newly-created idle source + **/ +GSource * +g_idle_source_new (void) +{ + GSource *source; + + source = g_source_new (&g_idle_funcs, sizeof (GSource)); + g_source_set_priority (source, G_PRIORITY_DEFAULT_IDLE); + + return source; +} + +/** + * g_idle_add_full: + * @priority: the priority of the idle source. Typically this will be in the + * range between #G_PRIORITY_DEFAULT_IDLE and #G_PRIORITY_HIGH_IDLE. + * @function: function to call + * @data: data to pass to @function + * @notify: 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 + * removed from the list of event sources and will not be called again. + * + * This internally creates a main loop source using g_idle_source_new() + * and attaches it to the main loop context using g_source_attach(). + * You can do these steps manually if you need greater control. + * + * Return value: the ID (greater than 0) of the event source. + **/ +guint +g_idle_add_full (gint priority, + GSourceFunc function, + gpointer data, + GDestroyNotify notify) +{ + GSource *source; + guint id; + + g_return_val_if_fail (function != NULL, 0); + + source = g_idle_source_new (); + + if (priority != G_PRIORITY_DEFAULT_IDLE) + g_source_set_priority (source, priority); + + g_source_set_callback (source, function, data, notify); + id = g_source_attach (source, NULL); + g_source_unref (source); + + return id; +} + +/** + * g_idle_add: + * @function: function to call + * @data: data to pass to @function. + * + * Adds a function to be called whenever there are no higher priority + * events pending to the default main loop. The function is given the + * default idle priority, #G_PRIORITY_DEFAULT_IDLE. If the function + * returns %FALSE it is automatically removed from the list of event + * sources and will not be called again. + * + * This internally creates a main loop source using g_idle_source_new() + * and attaches it to the main loop context using g_source_attach(). + * You can do these steps manually if you need greater control. + * + * Return value: the ID (greater than 0) of the event source. + **/ +guint +g_idle_add (GSourceFunc function, + gpointer data) +{ + return g_idle_add_full (G_PRIORITY_DEFAULT_IDLE, function, data, NULL); +} + +/** + * g_idle_remove_by_data: + * @data: the data for the idle source's callback. + * + * Removes the idle function with the given data. + * + * Return value: %TRUE if an idle source was found and removed. + **/ +gboolean +g_idle_remove_by_data (gpointer data) +{ + return g_source_remove_by_funcs_user_data (&g_idle_funcs, data); +} |