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glib/glib/gmain.c
Manish Singh f026692d2a glib/gasyncqueue.c glib/ghook.c g_return_if_fail -> g_return_val_if_fail 
Mon Nov  8 10:45:50 2004  Manish Singh  <yosh@gimp.org>

        * glib/gasyncqueue.c
        * glib/ghook.c
        * glib/giochannel.c: g_return_if_fail -> g_return_val_if_fail

        * glib/gmain.c: Ditto, plus also make g_main_context_ref() actually
        return the passed in pointer.
2004-11-08 18:49:35 +00:00

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/* 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
*/
#include "config.h"
/* uncomment the next line to get poll() debugging info */
/* #define G_MAIN_POLL_DEBUG */
#include "galias.h"
#include "glib.h"
#include "gthreadinit.h"
#include <signal.h>
#include <sys/types.h>
#include <time.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#endif /* HAVE_SYS_TIME_H */
#ifdef GLIB_HAVE_SYS_POLL_H
# include <sys/poll.h>
# undef events /* AIX 4.1.5 & 4.3.2 define this for SVR3,4 compatibility */
# undef revents /* AIX 4.1.5 & 4.3.2 define this for SVR3,4 compatibility */
/* The poll() emulation on OS/X doesn't handle fds=NULL, nfds=0,
* so we prefer our own poll emulation.
*/
#ifdef _POLL_EMUL_H_
#undef HAVE_POLL
#endif
#endif /* GLIB_HAVE_SYS_POLL_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 <net/socket.h>
#endif /* G_OS_BEOS */
#ifdef G_OS_UNIX
#include <fcntl.h>
#include <sys/wait.h>
#endif
/* 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
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;
GPollRec *poll_free_list;
GMemChunk *poll_chunk;
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;
};
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
{
gint priority;
GPollFD *fd;
GPollRec *next;
};
#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;
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
};
#ifdef HAVE_POLL
/* SunOS has poll, but doesn't provide a prototype. */
# if defined (sun) && !defined (__SVR4)
extern gint poll (GPollFD *ufds, guint nfsd, gint timeout);
# endif /* !sun */
#else /* !HAVE_POLL */
#ifdef G_OS_WIN32
static gint
g_poll (GPollFD *fds,
guint nfds,
gint timeout)
{
HANDLE handles[MAXIMUM_WAIT_OBJECTS];
gboolean poll_msgs = FALSE;
GPollFD *f;
DWORD ready;
MSG msg;
UINT timer;
gint nhandles = 0;
for (f = fds; f < &fds[nfds]; ++f)
if (f->fd >= 0)
{
if (f->fd == G_WIN32_MSG_HANDLE)
poll_msgs = TRUE;
else if (nhandles == MAXIMUM_WAIT_OBJECTS)
{
g_warning (G_STRLOC ": Too many handles to wait for!\n");
break;
}
else
{
#ifdef G_MAIN_POLL_DEBUG
g_print ("g_poll: waiting for %#x\n", f->fd);
#endif
handles[nhandles++] = (HANDLE) f->fd;
}
}
if (timeout == -1)
timeout = INFINITE;
if (poll_msgs)
{
/* Waiting for messages, and maybe events
* -> First PeekMessage
*/
#ifdef G_MAIN_POLL_DEBUG
g_print ("PeekMessage\n");
#endif
if (PeekMessage (&msg, NULL, 0, 0, PM_NOREMOVE))
ready = WAIT_OBJECT_0 + nhandles;
else
{
if (nhandles == 0)
{
/* Waiting just for messages */
if (timeout == INFINITE)
{
/* Infinite timeout
* -> WaitMessage
*/
#ifdef G_MAIN_POLL_DEBUG
g_print ("WaitMessage\n");
#endif
if (!WaitMessage ())
{
gchar *emsg = g_win32_error_message (GetLastError ());
g_warning (G_STRLOC ": WaitMessage() failed: %s", emsg);
g_free (emsg);
}
ready = WAIT_OBJECT_0 + nhandles;
}
else if (timeout == 0)
{
/* Waiting just for messages, zero timeout.
* If we got here, there was no message
*/
ready = WAIT_TIMEOUT;
}
else
{
/* Waiting just for messages, some timeout
* -> Set a timer, wait for message,
* kill timer, use PeekMessage
*/
timer = SetTimer (NULL, 0, timeout, NULL);
if (timer == 0)
{
gchar *emsg = g_win32_error_message (GetLastError ());
g_warning (G_STRLOC ": SetTimer() failed: %s", emsg);
g_free (emsg);
ready = WAIT_TIMEOUT;
}
else
{
#ifdef G_MAIN_POLL_DEBUG
g_print ("WaitMessage\n");
#endif
WaitMessage ();
KillTimer (NULL, timer);
#ifdef G_MAIN_POLL_DEBUG
g_print ("PeekMessage\n");
#endif
if (PeekMessage (&msg, NULL, 0, 0, PM_NOREMOVE)
&& msg.message != WM_TIMER)
ready = WAIT_OBJECT_0;
else
ready = WAIT_TIMEOUT;
}
}
}
else
{
/* Wait for either message or event
* -> Use MsgWaitForMultipleObjects
*/
#ifdef G_MAIN_POLL_DEBUG
g_print ("MsgWaitForMultipleObjects(%d, %d)\n", nhandles, timeout);
#endif
ready = MsgWaitForMultipleObjects (nhandles, handles, FALSE,
timeout, QS_ALLINPUT);
if (ready == WAIT_FAILED)
{
gchar *emsg = g_win32_error_message (GetLastError ());
g_warning (G_STRLOC ": MsgWaitForMultipleObjects() failed: %s", emsg);
g_free (emsg);
}
}
}
}
else if (nhandles == 0)
{
/* Wait for nothing (huh?) */
return 0;
}
else
{
/* Wait for just events
* -> Use WaitForMultipleObjects
*/
#ifdef G_MAIN_POLL_DEBUG
g_print ("WaitForMultipleObjects(%d, %d)\n", nhandles, timeout);
#endif
ready = WaitForMultipleObjects (nhandles, handles, FALSE, timeout);
if (ready == WAIT_FAILED)
{
gchar *emsg = g_win32_error_message (GetLastError ());
g_warning (G_STRLOC ": WaitForMultipleObjects() failed: %s", emsg);
g_free (emsg);
}
}
#ifdef G_MAIN_POLL_DEBUG
g_print ("wait returns %ld%s\n",
ready,
(ready == WAIT_FAILED ? " (WAIT_FAILED)" :
(ready == WAIT_TIMEOUT ? " (WAIT_TIMEOUT)" :
(poll_msgs && ready == WAIT_OBJECT_0 + nhandles ? " (msg)" : ""))));
#endif
for (f = fds; f < &fds[nfds]; ++f)
f->revents = 0;
if (ready == WAIT_FAILED)
return -1;
else if (ready == WAIT_TIMEOUT)
return 0;
else if (poll_msgs && ready == WAIT_OBJECT_0 + nhandles)
{
for (f = fds; f < &fds[nfds]; ++f)
if (f->fd >= 0)
{
if (f->events & G_IO_IN)
if (f->fd == G_WIN32_MSG_HANDLE)
f->revents |= G_IO_IN;
}
}
#if 1 /* TEST_WITHOUT_THIS */
else if (ready >= WAIT_OBJECT_0 && ready < WAIT_OBJECT_0 + nhandles)
for (f = fds; f < &fds[nfds]; ++f)
{
if ((f->events & (G_IO_IN | G_IO_OUT))
&& f->fd == (gint) handles[ready - WAIT_OBJECT_0])
{
if (f->events & G_IO_IN)
f->revents |= G_IO_IN;
else
f->revents |= G_IO_OUT;
#ifdef G_MAIN_POLL_DEBUG
g_print ("g_poll: got event %#x\n", f->fd);
#endif
#if 0
ResetEvent ((HANDLE) f->fd);
#endif
}
}
#endif
return 1;
}
#else /* !G_OS_WIN32 */
/* The following implementation of poll() comes from the GNU C Library.
* Copyright (C) 1994, 1996, 1997 Free Software Foundation, Inc.
*/
#include <string.h> /* for bzero on BSD systems */
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif /* HAVE_SYS_SELECT_H */
#ifdef G_OS_BEOS
#undef NO_FD_SET
#endif /* G_OS_BEOS */
#ifndef NO_FD_SET
# define SELECT_MASK fd_set
#else /* !NO_FD_SET */
# ifndef _AIX
typedef long fd_mask;
# endif /* _AIX */
# ifdef _IBMR2
# define SELECT_MASK void
# else /* !_IBMR2 */
# define SELECT_MASK int
# endif /* !_IBMR2 */
#endif /* !NO_FD_SET */
static gint
g_poll (GPollFD *fds,
guint nfds,
gint timeout)
{
struct timeval tv;
SELECT_MASK rset, wset, xset;
GPollFD *f;
int ready;
int maxfd = 0;
FD_ZERO (&rset);
FD_ZERO (&wset);
FD_ZERO (&xset);
for (f = fds; f < &fds[nfds]; ++f)
if (f->fd >= 0)
{
if (f->events & G_IO_IN)
FD_SET (f->fd, &rset);
if (f->events & G_IO_OUT)
FD_SET (f->fd, &wset);
if (f->events & G_IO_PRI)
FD_SET (f->fd, &xset);
if (f->fd > maxfd && (f->events & (G_IO_IN|G_IO_OUT|G_IO_PRI)))
maxfd = f->fd;
}
tv.tv_sec = timeout / 1000;
tv.tv_usec = (timeout % 1000) * 1000;
ready = select (maxfd + 1, &rset, &wset, &xset,
timeout == -1 ? NULL : &tv);
if (ready > 0)
for (f = fds; f < &fds[nfds]; ++f)
{
f->revents = 0;
if (f->fd >= 0)
{
if (FD_ISSET (f->fd, &rset))
f->revents |= G_IO_IN;
if (FD_ISSET (f->fd, &wset))
f->revents |= G_IO_OUT;
if (FD_ISSET (f->fd, &xset))
f->revents |= G_IO_PRI;
}
}
return ready;
}
#endif /* !G_OS_WIN32 */
#endif /* !HAVE_POLL */
/**
* 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;
}
/* If DISABLE_MEM_POOLS is defined, then freeing the
* mem chunk won't free the records, so we have to
* do it manually. The conditionalization here is
* an optimization; g_mem_chunk_free() is a no-op
* when DISABLE_MEM_POOLS is set.
*/
#ifdef DISABLE_MEM_POOLS
static void
poll_rec_list_free (GMainContext *context,
GPollRec *list)
{
while (list)
{
GPollRec *tmp_rec = list;
list = list->next;
g_chunk_free (tmp_rec, context->poll_chunk);
}
}
#endif /* DISABLE_MEM_POOLS */
/**
* 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, TRUE);
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);
#ifdef DISABLE_MEM_POLLS
poll_rec_list_free (context, context->poll_records);
poll_rec_list_free (context, context->poll_free_list);
#endif /* DISABLE_MEM_POOLS */
if (context->poll_chunk)
g_mem_chunk_destroy (context->poll_chunk);
#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);
#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;
if (pipe (context->wake_up_pipe) < 0)
g_error ("Cannot create pipe main loop wake-up: %s\n",
g_strerror (errno));
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 = (gint) context->wake_up_semaphore;
context->wake_up_rec.events = G_IO_IN;
# ifdef G_MAIN_POLL_DEBUG
g_print ("wake-up semaphore: %#x\n", (guint) context->wake_up_semaphore);
# endif
# 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 strcuture
*
* Return value: the new #GMainContext
**/
GMainContext *
g_main_context_new (void)
{
GMainContext *context = g_new0 (GMainContext, 1);
#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;
#if HAVE_POLL
context->poll_func = (GPollFunc)poll;
#else
context->poll_func = g_poll;
#endif
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);
G_UNLOCK (main_context_list);
return context;
}
/**
* g_main_context_default:
*
* Returns the default main context. This is the main context used
* for main loop functions when a main loop is not explicitly
* specified.
*
* Return value: the 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 ();
G_UNLOCK (main_loop);
return default_main_context;
}
/* 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.
*
* Return value: the ID 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 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 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_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_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_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().
*
* 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
/* Avoid calling time() except for the first time.
* GetTickCount() should be pretty fast and low-level?
* I could also use ftime() but it seems unnecessarily overheady.
*/
static DWORD start_tick = 0;
static time_t start_time;
DWORD tick;
g_return_if_fail (result != NULL);
if (start_tick == 0)
{
start_tick = GetTickCount ();
time (&start_time);
}
tick = GetTickCount ();
result->tv_sec = (tick - start_tick) / 1000 + start_time;
result->tv_usec = ((tick - start_tick) % 1000) * 1000;
#endif
}
/* Running the main loop */
static gint *
get_depth_pointer (void)
{
static GStaticPrivate depth_private = G_STATIC_PRIVATE_INIT;
gint *depth_pointer = g_static_private_get (&depth_private);
if (!depth_pointer)
{
depth_pointer = g_new (gint, 1);
*depth_pointer = 0;
g_static_private_set (&depth_private, depth_pointer, g_free);
}
return depth_pointer;
}
/**
* g_main_depth:
*
* Return value: The main loop recursion level in the current thread
*
* 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.
*
* <example>
* 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();
* }
* </example>
*
* 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()
*
* <example>
* 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;
* }
* }
* </example>
*
* 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>
**/
int
g_main_depth (void)
{
gint *depth = get_depth_pointer ();
return *depth;
}
/* 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)
{
gint *depth = get_depth_pointer ();
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);
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);
(*depth)++;
need_destroy = ! dispatch (source,
callback,
user_data);
(*depth)--;
LOCK_CONTEXT (context);
if (cb_funcs)
cb_funcs->unref (cb_data);
if (!was_in_call)
source->flags &= ~G_HOOK_FLAG_IN_CALL;
if ((source->flags & G_SOURCE_CAN_RECURSE) == 0 &&
!SOURCE_DESTROYED (source))
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 context 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 only release ownership 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, &current_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)
{
if (pollrec->fd->events)
{
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;
}
n_poll++;
}
pollrec = pollrec->next;
}
#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 0;
}
#endif /* G_THREADS_ENABLED */
pollrec = context->poll_records;
i = 0;
while (i < n_fds)
{
if (pollrec->fd->events)
{
pollrec->fd->revents = fds[i].revents;
i++;
}
pollrec = pollrec->next;
}
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;
g_return_val_if_fail (g_thread_supported (), FALSE);
if (!block)
return FALSE;
LOCK_CONTEXT (context);
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)
{
UNLOCK_CONTEXT (context);
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. 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.
**/
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
g_print ("g_main_poll(%d) timeout: %d\n", 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
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;
i = 0;
while (i < n_fds)
{
if (pollrec->fd->events)
{
if (fds[i].revents)
{
g_print (" [%d:", 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, *newrec;
if (!context->poll_chunk)
context->poll_chunk = g_mem_chunk_create (GPollRec, 32, G_ALLOC_ONLY);
if (context->poll_free_list)
{
newrec = context->poll_free_list;
context->poll_free_list = newrec->next;
}
else
newrec = g_chunk_new (GPollRec, context->poll_chunk);
/* 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;
#ifdef ENABLE_GC_FRIENDLY
pollrec->fd = NULL;
#endif /* ENABLE_GC_FRIENDLY */
pollrec->next = context->poll_free_list;
context->poll_free_list = 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
{
#ifdef HAVE_POLL
context->poll_func = (GPollFunc) poll;
#else
context->poll_func = (GPollFunc) g_poll;
#endif
}
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);
}
/* 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++;
}
}
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, &current_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, &current_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, &current_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, &current_time);
g_timeout_set_expiration (timeout_source, &current_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 (&current_time);
g_timeout_set_expiration (timeout_source, &current_time);
return source;
}
/**
* g_timeout_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.
* @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 idle 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).
*
* Return value: the id of 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).
*
* Return value: the id of event source.
**/
guint
g_timeout_add (guint32 interval,
GSourceFunc function,
gpointer data)
{
return g_timeout_add_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)
{
GChildWatchSource *child_watch_source;
*timeout = -1;
child_watch_source = (GChildWatchSource *) source;
return check_for_child_exited (source);
}
static gboolean
g_child_watch_check (GSource *source)
{
GChildWatchSource *child_watch_source;
child_watch_source = (GChildWatchSource *) 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_RESTART | SA_NOCLDSTOP;
sigaction (SIGCHLD, &action, NULL);
}
static gpointer
child_watch_helper_thread (gpointer data)
{
GPollFD fds;
GPollFunc poll_func;
#ifdef HAVE_POLL
poll_func = (GPollFunc)poll;
#else
poll_func = g_poll;
#endif
fds.fd = child_watch_wake_up_pipe[0];
fds.events = G_IO_IN;
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);
}
return NULL;
}
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 id of a child process to watch. On Windows, a HANDLE
* for the process to watch (which actually 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 on platforms where #GPid must be explicitely 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.
*
* 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 = (int)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 id of a child process to watch
* @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 a
* default priority, #G_PRIORITY_DEFAULT.
*
* Note that on platforms where #GPid must be explicitely 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.
*
* Return value: the id of 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 of a child process to watch
* @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.
*
* Note that on platforms where #GPid must be explicitely 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.
*
* Return value: the id of 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 btweeen #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.
*
* Return value: the id 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.
*
* Return value: the id 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);
}
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