forked from AuroraMiddleware/gtk
888dfe499d
GDK has a lock to mark critical sections inside the backends. Additionally, code that would re-enter into the GTK main loop was supposed to hold the lock. Back in the Good Old Days™ this was guaranteed to kind of work only on the X11 backend, and would cause a neat explosion on any other GDK backend. During GTK+ 3.x we deprecated the API to enter and leave the critical sections, and now we can remove all the internal uses of the lock, since external API that uses GTK+ 4.x won't be able to hold the GDK lock. https://bugzilla.gnome.org/show_bug.cgi?id=793124
1047 lines
32 KiB
C
1047 lines
32 KiB
C
#include "config.h"
|
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|
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#include <glib.h>
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#include <pthread.h>
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#include <sys/types.h>
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#include <sys/uio.h>
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#include <unistd.h>
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|
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#include "gdkprivate-quartz.h"
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#include <gdk/gdkdisplayprivate.h>
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/*
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* This file implementations integration between the GLib main loop and
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* the native system of the Core Foundation run loop and Cocoa event
|
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* handling. There are basically two different cases that we need to
|
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* handle: either the GLib main loop is in control (the application
|
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* has called gtk_main(), or is otherwise iterating the main loop), or
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* CFRunLoop is in control (we are in a modal operation such as window
|
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* resizing or drag-and-drop.)
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*
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* When the GLib main loop is in control we integrate in native event
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* handling in two ways: first we add a GSource that handles checking
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* whether there are native events available, translating native events
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* to GDK events, and dispatching GDK events. Second we replace the
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* "poll function" of the GLib main loop with our own version that knows
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* how to wait for both the file descriptors and timeouts that GLib is
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* interested in and also for incoming native events.
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*
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* When CFRunLoop is in control, we integrate in GLib main loop handling
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* by adding a "run loop observer" that gives us notification at various
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* points in the run loop cycle. We map these points onto the corresponding
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* stages of the GLib main loop (prepare, check, dispatch), and make the
|
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* appropriate calls into GLib.
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*
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* Both cases share a single problem: the OS X API’s don’t allow us to
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* wait simultaneously for file descriptors and for events. So when we
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* need to do a blocking wait that includes file descriptor activity, we
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* push the actual work of calling select() to a helper thread (the
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* "select thread") and wait for native events in the main thread.
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*
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* The main known limitation of this code is that if a callback is triggered
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* via the OS X run loop while we are "polling" (in either case described
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* above), iteration of the GLib main loop is not possible from within
|
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* that callback. If the programmer tries to do so explicitly, then they
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* will get a warning from GLib "main loop already active in another thread".
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*/
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/******* State for run loop iteration *******/
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/* Count of number of times we've gotten an "Entry" notification for
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* our run loop observer.
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*/
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static int current_loop_level = 0;
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/* Run loop level at which we acquired ownership of the GLib main
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* loop. See note in run_loop_entry(). -1 means that we don’t have
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* ownership
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*/
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static int acquired_loop_level = -1;
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/* Between run_loop_before_waiting() and run_loop_after_waiting();
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* whether we we need to call select_thread_collect_poll()
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*/
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static gboolean run_loop_polling_async = FALSE;
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/* Between run_loop_before_waiting() and run_loop_after_waiting();
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* max_prioritiy to pass to g_main_loop_check()
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*/
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static gint run_loop_max_priority;
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/* Timer that we've added to wake up the run loop when a GLib timeout
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*/
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static CFRunLoopTimerRef run_loop_timer = NULL;
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/* These are the file descriptors that are we are polling out of
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* the run loop. (We keep the array around and reuse it to avoid
|
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* constant allocations.)
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*/
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#define RUN_LOOP_POLLFDS_INITIAL_SIZE 16
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static GPollFD *run_loop_pollfds;
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static guint run_loop_pollfds_size; /* Allocated size of the array */
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static guint run_loop_n_pollfds; /* Number of file descriptors in the array */
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/******* Other global variables *******/
|
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|
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/* Since we count on replacing the GLib main loop poll function as our
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* method of integrating Cocoa event handling into the GLib main loop
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* we need to make sure that the poll function is always called even
|
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* when there are no file descriptors that need to be polled. To do
|
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* this, we add a dummy GPollFD to our event source with a file
|
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* descriptor of “-1”. Then any time that GLib is polling the event
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* source, it will call our poll function.
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*/
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static GPollFD event_poll_fd;
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|
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/* Current NSEvents that we've gotten from Cocoa but haven't yet converted
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* to GdkEvents. We wait until our dispatch() function to do the conversion
|
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* since the conversion can conceivably cause signals to be emmitted
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* or other things that shouldn’t happen inside a poll function.
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*/
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static GQueue *current_events;
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|
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/* The default poll function for GLib; we replace this with our own
|
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* Cocoa-aware version and then call the old version to do actual
|
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* file descriptor polling. There’s no actual need to chain to the
|
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* old one; we could reimplement the same functionality from scratch,
|
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* but since the default implementation does the right thing, why
|
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* bother.
|
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*/
|
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static GPollFunc old_poll_func;
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|
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/* Reference to the run loop of the main thread. (There is a unique
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* CFRunLoop per thread.)
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*/
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static CFRunLoopRef main_thread_run_loop;
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/* Normally the Cocoa main loop maintains an NSAutoReleasePool and frees
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* it on every iteration. Since we are replacing the main loop we have
|
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* to provide this functionality ourself. We free and replace the
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* auto-release pool in our sources prepare() function.
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*/
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static NSAutoreleasePool *autorelease_pool;
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|
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/* Flag when we've called nextEventMatchingMask ourself; this triggers
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* a run loop iteration, so we need to detect that and avoid triggering
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* our "run the GLib main looop while the run loop is active machinery.
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*/
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static gint getting_events = 0;
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/************************************************************
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********* Select Thread *********
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************************************************************/
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/* The states in our state machine, see comments in select_thread_func()
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* for descriptiions of each state
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*/
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typedef enum {
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BEFORE_START,
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WAITING,
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POLLING_QUEUED,
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POLLING_RESTART,
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POLLING_DESCRIPTORS,
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} SelectThreadState;
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#ifdef G_ENABLE_DEBUG
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static const char *const state_names[] = {
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"BEFORE_START",
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"WAITING",
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"POLLING_QUEUED",
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"POLLING_RESTART",
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"POLLING_DESCRIPTORS"
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};
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#endif
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static SelectThreadState select_thread_state = BEFORE_START;
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static pthread_t select_thread;
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static pthread_mutex_t select_thread_mutex = PTHREAD_MUTEX_INITIALIZER;
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static pthread_cond_t select_thread_cond = PTHREAD_COND_INITIALIZER;
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#define SELECT_THREAD_LOCK() pthread_mutex_lock (&select_thread_mutex)
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#define SELECT_THREAD_UNLOCK() pthread_mutex_unlock (&select_thread_mutex)
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#define SELECT_THREAD_SIGNAL() pthread_cond_signal (&select_thread_cond)
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#define SELECT_THREAD_WAIT() pthread_cond_wait (&select_thread_cond, &select_thread_mutex)
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/* These are the file descriptors that the select thread is currently
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* polling.
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*/
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static GPollFD *current_pollfds;
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static guint current_n_pollfds;
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/* These are the file descriptors that the select thread should pick
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* up and start polling when it has a chance.
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*/
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static GPollFD *next_pollfds;
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static guint next_n_pollfds;
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/* Pipe used to wake up the select thread */
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static gint select_thread_wakeup_pipe[2];
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/* Run loop source used to wake up the main thread */
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static CFRunLoopSourceRef select_main_thread_source;
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static void
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select_thread_set_state (SelectThreadState new_state)
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{
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gboolean old_state;
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if (select_thread_state == new_state)
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return;
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GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Select thread state: %s => %s", state_names[select_thread_state], state_names[new_state]));
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old_state = select_thread_state;
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select_thread_state = new_state;
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if (old_state == WAITING && new_state != WAITING)
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SELECT_THREAD_SIGNAL ();
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}
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static void
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signal_main_thread (void)
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{
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GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Waking up main thread"));
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/* If we are in nextEventMatchingMask, then we need to make sure an
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* event gets queued, otherwise it's enough to simply wake up the
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* main thread run loop
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*/
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if (!run_loop_polling_async)
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CFRunLoopSourceSignal (select_main_thread_source);
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/* Don't check for CFRunLoopIsWaiting() here because it causes a
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* race condition (the loop could go into waiting state right after
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* we checked).
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*/
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CFRunLoopWakeUp (main_thread_run_loop);
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}
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static void *
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select_thread_func (void *arg)
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{
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char c;
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SELECT_THREAD_LOCK ();
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while (TRUE)
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{
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switch (select_thread_state)
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{
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case BEFORE_START:
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/* The select thread has not been started yet
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*/
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g_assert_not_reached ();
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case WAITING:
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/* Waiting for a set of file descriptors to be submitted by the main thread
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*
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* => POLLING_QUEUED: main thread thread submits a set of file descriptors
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*/
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SELECT_THREAD_WAIT ();
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break;
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case POLLING_QUEUED:
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/* Waiting for a set of file descriptors to be submitted by the main thread
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*
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* => POLLING_DESCRIPTORS: select thread picks up the file descriptors to begin polling
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*/
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g_free (current_pollfds);
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current_pollfds = next_pollfds;
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current_n_pollfds = next_n_pollfds;
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next_pollfds = NULL;
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next_n_pollfds = 0;
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select_thread_set_state (POLLING_DESCRIPTORS);
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break;
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case POLLING_RESTART:
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/* Select thread is currently polling a set of file descriptors, main thread has
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* began a new iteration with the same set of file descriptors. We don't want to
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* wake the select thread up and wait for it to restart immediately, but to avoid
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* a race (described below in select_thread_start_polling()) we need to recheck after
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* polling completes.
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*
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* => POLLING_DESCRIPTORS: select completes, main thread rechecks by polling again
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* => POLLING_QUEUED: main thread submits a new set of file descriptors to be polled
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*/
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select_thread_set_state (POLLING_DESCRIPTORS);
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break;
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case POLLING_DESCRIPTORS:
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/* In the process of polling the file descriptors
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*
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* => WAITING: polling completes when a file descriptor becomes active
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* => POLLING_QUEUED: main thread submits a new set of file descriptors to be polled
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* => POLLING_RESTART: main thread begins a new iteration with the same set file descriptors
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*/
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SELECT_THREAD_UNLOCK ();
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old_poll_func (current_pollfds, current_n_pollfds, -1);
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SELECT_THREAD_LOCK ();
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read (select_thread_wakeup_pipe[0], &c, 1);
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if (select_thread_state == POLLING_DESCRIPTORS)
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{
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signal_main_thread ();
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select_thread_set_state (WAITING);
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}
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break;
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}
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}
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}
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static void
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got_fd_activity (void *info)
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{
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NSEvent *event;
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||
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/* Post a message so we'll break out of the message loop */
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event = [NSEvent otherEventWithType: NSApplicationDefined
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location: NSZeroPoint
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modifierFlags: 0
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timestamp: 0
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windowNumber: 0
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||
context: nil
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subtype: GDK_QUARTZ_EVENT_SUBTYPE_EVENTLOOP
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data1: 0
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data2: 0];
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[NSApp postEvent:event atStart:YES];
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}
|
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|
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static void
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select_thread_start (void)
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{
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g_return_if_fail (select_thread_state == BEFORE_START);
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pipe (select_thread_wakeup_pipe);
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fcntl (select_thread_wakeup_pipe[0], F_SETFL, O_NONBLOCK);
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CFRunLoopSourceContext source_context = {0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, got_fd_activity };
|
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select_main_thread_source = CFRunLoopSourceCreate (NULL, 0, &source_context);
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CFRunLoopAddSource (main_thread_run_loop, select_main_thread_source, kCFRunLoopCommonModes);
|
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select_thread_state = WAITING;
|
||
|
||
while (TRUE)
|
||
{
|
||
if (pthread_create (&select_thread, NULL, select_thread_func, NULL) == 0)
|
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break;
|
||
|
||
g_warning ("Failed to create select thread, sleeping and trying again");
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sleep (1);
|
||
}
|
||
}
|
||
|
||
#ifdef G_ENABLE_DEBUG
|
||
static void
|
||
dump_poll_result (GPollFD *ufds,
|
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guint nfds)
|
||
{
|
||
GString *s;
|
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gint i;
|
||
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s = g_string_new ("");
|
||
for (i = 0; i < nfds; i++)
|
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{
|
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if (ufds[i].fd >= 0 && ufds[i].revents)
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{
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g_string_append_printf (s, " %d:", ufds[i].fd);
|
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if (ufds[i].revents & G_IO_IN)
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g_string_append (s, " in");
|
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if (ufds[i].revents & G_IO_OUT)
|
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g_string_append (s, " out");
|
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if (ufds[i].revents & G_IO_PRI)
|
||
g_string_append (s, " pri");
|
||
g_string_append (s, "\n");
|
||
}
|
||
}
|
||
g_message ("%s", s->str);
|
||
g_string_free (s, TRUE);
|
||
}
|
||
#endif
|
||
|
||
gboolean
|
||
pollfds_equal (GPollFD *old_pollfds,
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||
guint old_n_pollfds,
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GPollFD *new_pollfds,
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||
guint new_n_pollfds)
|
||
{
|
||
gint i;
|
||
|
||
if (old_n_pollfds != new_n_pollfds)
|
||
return FALSE;
|
||
|
||
for (i = 0; i < old_n_pollfds; i++)
|
||
{
|
||
if (old_pollfds[i].fd != new_pollfds[i].fd ||
|
||
old_pollfds[i].events != new_pollfds[i].events)
|
||
return FALSE;
|
||
}
|
||
|
||
return TRUE;
|
||
}
|
||
|
||
/* Begins a polling operation with the specified GPollFD array; the
|
||
* timeout is used only to tell if the polling operation is blocking
|
||
* or non-blocking.
|
||
*
|
||
* Returns:
|
||
* -1: No file descriptors ready, began asynchronous poll
|
||
* 0: No file descriptors ready, asynchronous poll not needed
|
||
* > 0: Number of file descriptors ready
|
||
*/
|
||
static gint
|
||
select_thread_start_poll (GPollFD *ufds,
|
||
guint nfds, gint timeout)
|
||
{
|
||
gint n_ready;
|
||
gboolean have_new_pollfds = FALSE;
|
||
gint poll_fd_index = -1;
|
||
gint i;
|
||
|
||
for (i = 0; i < nfds; i++)
|
||
if (ufds[i].fd == -1)
|
||
{
|
||
poll_fd_index = i;
|
||
break;
|
||
}
|
||
|
||
if (nfds == 0 ||
|
||
(nfds == 1 && poll_fd_index >= 0))
|
||
{
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Nothing to poll"));
|
||
return 0;
|
||
}
|
||
|
||
/* If we went immediately to an async poll, then we might decide to
|
||
* dispatch idle functions when higher priority file descriptor sources
|
||
* are ready to be dispatched. So we always need to first check
|
||
* check synchronously with a timeout of zero, and only when no
|
||
* sources are immediately ready, go to the asynchronous poll.
|
||
*
|
||
* Of course, if the timeout passed in is 0, then the synchronous
|
||
* check is sufficient and we never need to do the asynchronous poll.
|
||
*/
|
||
n_ready = old_poll_func (ufds, nfds, 0);
|
||
if (n_ready > 0 || timeout == 0)
|
||
{
|
||
#ifdef G_ENABLE_DEBUG
|
||
if ((_gdk_debug_flags & GDK_DEBUG_EVENTLOOP) && n_ready > 0)
|
||
{
|
||
g_message ("EventLoop: Found ready file descriptors before waiting");
|
||
dump_poll_result (ufds, nfds);
|
||
}
|
||
#endif
|
||
|
||
return n_ready;
|
||
}
|
||
|
||
SELECT_THREAD_LOCK ();
|
||
|
||
if (select_thread_state == BEFORE_START)
|
||
{
|
||
select_thread_start ();
|
||
}
|
||
|
||
if (select_thread_state == POLLING_QUEUED)
|
||
{
|
||
/* If the select thread hasn't picked up the set of file descriptors yet
|
||
* then we can simply replace an old stale set with a new set.
|
||
*/
|
||
if (!pollfds_equal (ufds, nfds, next_pollfds, next_n_pollfds - 1))
|
||
{
|
||
g_free (next_pollfds);
|
||
next_pollfds = NULL;
|
||
next_n_pollfds = 0;
|
||
|
||
have_new_pollfds = TRUE;
|
||
}
|
||
}
|
||
else if (select_thread_state == POLLING_RESTART || select_thread_state == POLLING_DESCRIPTORS)
|
||
{
|
||
/* If we are already in the process of polling the right set of file descriptors,
|
||
* there's no need for us to immediately force the select thread to stop polling
|
||
* and then restart again. And avoiding doing so increases the efficiency considerably
|
||
* in the common case where we have a set of basically inactive file descriptors that
|
||
* stay unchanged present as we process many events.
|
||
*
|
||
* However, we have to be careful that we don't hit the following race condition
|
||
* Select Thread Main Thread
|
||
* ----------------- ---------------
|
||
* Polling Completes
|
||
* Reads data or otherwise changes file descriptor state
|
||
* Checks if polling is current
|
||
* Does nothing (*)
|
||
* Releases lock
|
||
* Acquires lock
|
||
* Marks polling as complete
|
||
* Wakes main thread
|
||
* Receives old stale file descriptor state
|
||
*
|
||
* To avoid this, when the new set of poll descriptors is the same as the current
|
||
* one, we transition to the POLLING_RESTART stage at the point marked (*). When
|
||
* the select thread wakes up from the poll because a file descriptor is active, if
|
||
* the state is POLLING_RESTART it immediately begins polling same the file descriptor
|
||
* set again. This normally will just return the same set of active file descriptors
|
||
* as the first time, but in sequence described above will properly update the
|
||
* file descriptor state.
|
||
*
|
||
* Special case: this RESTART logic is not needed if the only FD is the internal GLib
|
||
* "wakeup pipe" that is presented when threads are initialized.
|
||
*
|
||
* P.S.: The harm in the above sequence is mostly that sources can be signalled
|
||
* as ready when they are no longer ready. This may prompt a blocking read
|
||
* from a file descriptor that hangs.
|
||
*/
|
||
if (!pollfds_equal (ufds, nfds, current_pollfds, current_n_pollfds - 1))
|
||
have_new_pollfds = TRUE;
|
||
else
|
||
{
|
||
if (!((nfds == 1 && poll_fd_index < 0 && g_thread_supported ()) ||
|
||
(nfds == 2 && poll_fd_index >= 0 && g_thread_supported ())))
|
||
select_thread_set_state (POLLING_RESTART);
|
||
}
|
||
}
|
||
else
|
||
have_new_pollfds = TRUE;
|
||
|
||
if (have_new_pollfds)
|
||
{
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Submitting a new set of file descriptor to the select thread"));
|
||
|
||
g_assert (next_pollfds == NULL);
|
||
|
||
next_n_pollfds = nfds + 1;
|
||
next_pollfds = g_new (GPollFD, nfds + 1);
|
||
memcpy (next_pollfds, ufds, nfds * sizeof (GPollFD));
|
||
|
||
next_pollfds[nfds].fd = select_thread_wakeup_pipe[0];
|
||
next_pollfds[nfds].events = G_IO_IN;
|
||
|
||
if (select_thread_state != POLLING_QUEUED && select_thread_state != WAITING)
|
||
{
|
||
if (select_thread_wakeup_pipe[1])
|
||
{
|
||
char c = 'A';
|
||
write (select_thread_wakeup_pipe[1], &c, 1);
|
||
}
|
||
}
|
||
|
||
select_thread_set_state (POLLING_QUEUED);
|
||
}
|
||
|
||
SELECT_THREAD_UNLOCK ();
|
||
|
||
return -1;
|
||
}
|
||
|
||
/* End an asynchronous polling operation started with
|
||
* select_thread_collect_poll(). This must be called if and only if
|
||
* select_thread_start_poll() return -1. The GPollFD array passed
|
||
* in must be identical to the one passed to select_thread_start_poll().
|
||
*
|
||
* The results of the poll are written into the GPollFD array passed in.
|
||
*
|
||
* Returns: number of file descriptors ready
|
||
*/
|
||
static int
|
||
select_thread_collect_poll (GPollFD *ufds, guint nfds)
|
||
{
|
||
gint i;
|
||
gint n_ready = 0;
|
||
|
||
SELECT_THREAD_LOCK ();
|
||
|
||
if (select_thread_state == WAITING) /* The poll completed */
|
||
{
|
||
for (i = 0; i < nfds; i++)
|
||
{
|
||
if (ufds[i].fd == -1)
|
||
continue;
|
||
|
||
g_assert (ufds[i].fd == current_pollfds[i].fd);
|
||
g_assert (ufds[i].events == current_pollfds[i].events);
|
||
|
||
if (current_pollfds[i].revents)
|
||
{
|
||
ufds[i].revents = current_pollfds[i].revents;
|
||
n_ready++;
|
||
}
|
||
}
|
||
|
||
#ifdef G_ENABLE_DEBUG
|
||
if (_gdk_debug_flags & GDK_DEBUG_EVENTLOOP)
|
||
{
|
||
g_message ("EventLoop: Found ready file descriptors after waiting");
|
||
dump_poll_result (ufds, nfds);
|
||
}
|
||
#endif
|
||
}
|
||
|
||
SELECT_THREAD_UNLOCK ();
|
||
|
||
return n_ready;
|
||
}
|
||
|
||
/************************************************************
|
||
********* Main Loop Source *********
|
||
************************************************************/
|
||
|
||
gboolean
|
||
_gdk_quartz_event_loop_check_pending (void)
|
||
{
|
||
return current_events && current_events->head;
|
||
}
|
||
|
||
NSEvent*
|
||
_gdk_quartz_event_loop_get_pending (void)
|
||
{
|
||
NSEvent *event = NULL;
|
||
|
||
if (current_events)
|
||
event = g_queue_pop_tail (current_events);
|
||
|
||
return event;
|
||
}
|
||
|
||
void
|
||
_gdk_quartz_event_loop_release_event (NSEvent *event)
|
||
{
|
||
[event release];
|
||
}
|
||
|
||
static gboolean
|
||
gdk_event_prepare (GSource *source,
|
||
gint *timeout)
|
||
{
|
||
gboolean retval;
|
||
|
||
/* The prepare stage is the stage before the main loop starts polling
|
||
* and dispatching events. The autorelease poll is drained here for
|
||
* the preceding main loop iteration or, in case of the first iteration,
|
||
* for the operations carried out between event loop initialization and
|
||
* this first iteration.
|
||
*
|
||
* The autorelease poll must only be drained when the following conditions
|
||
* apply:
|
||
* - We are at the base CFRunLoop level (indicated by current_loop_level),
|
||
* - We are at the base g_main_loop level (indicated by
|
||
* g_main_depth())
|
||
* - We are at the base poll_func level (indicated by getting events).
|
||
*
|
||
* Messing with the autorelease pool at any level of nesting can cause access
|
||
* to deallocated memory because autorelease_pool is static and releasing a
|
||
* pool will cause all pools allocated inside of it to be released as well.
|
||
*/
|
||
if (current_loop_level == 0 && g_main_depth() == 0 && getting_events == 0)
|
||
{
|
||
if (autorelease_pool)
|
||
[autorelease_pool drain];
|
||
|
||
autorelease_pool = [[NSAutoreleasePool alloc] init];
|
||
}
|
||
|
||
*timeout = -1;
|
||
|
||
if (_gdk_display->event_pause_count > 0)
|
||
retval = _gdk_event_queue_find_first (_gdk_display) != NULL;
|
||
else
|
||
retval = (_gdk_event_queue_find_first (_gdk_display) != NULL ||
|
||
_gdk_quartz_event_loop_check_pending ());
|
||
|
||
return retval;
|
||
}
|
||
|
||
static gboolean
|
||
gdk_event_check (GSource *source)
|
||
{
|
||
gboolean retval;
|
||
|
||
if (_gdk_display->event_pause_count > 0)
|
||
retval = _gdk_event_queue_find_first (_gdk_display) != NULL;
|
||
else
|
||
retval = (_gdk_event_queue_find_first (_gdk_display) != NULL ||
|
||
_gdk_quartz_event_loop_check_pending ());
|
||
|
||
return retval;
|
||
}
|
||
|
||
static gboolean
|
||
gdk_event_dispatch (GSource *source,
|
||
GSourceFunc callback,
|
||
gpointer user_data)
|
||
{
|
||
GdkEvent *event;
|
||
|
||
_gdk_quartz_display_queue_events (_gdk_display);
|
||
|
||
event = _gdk_event_unqueue (_gdk_display);
|
||
|
||
if (event)
|
||
{
|
||
_gdk_event_emit (event);
|
||
|
||
gdk_event_free (event);
|
||
}
|
||
|
||
return TRUE;
|
||
}
|
||
|
||
static GSourceFuncs event_funcs = {
|
||
gdk_event_prepare,
|
||
gdk_event_check,
|
||
gdk_event_dispatch,
|
||
NULL
|
||
};
|
||
|
||
/************************************************************
|
||
********* Our Poll Function *********
|
||
************************************************************/
|
||
|
||
static gint
|
||
poll_func (GPollFD *ufds,
|
||
guint nfds,
|
||
gint timeout_)
|
||
{
|
||
NSEvent *event;
|
||
NSDate *limit_date;
|
||
gint n_ready;
|
||
|
||
static GPollFD *last_ufds;
|
||
|
||
last_ufds = ufds;
|
||
|
||
n_ready = select_thread_start_poll (ufds, nfds, timeout_);
|
||
if (n_ready > 0)
|
||
timeout_ = 0;
|
||
|
||
if (timeout_ == -1)
|
||
limit_date = [NSDate distantFuture];
|
||
else if (timeout_ == 0)
|
||
limit_date = [NSDate distantPast];
|
||
else
|
||
limit_date = [NSDate dateWithTimeIntervalSinceNow:timeout_/1000.0];
|
||
|
||
getting_events++;
|
||
event = [NSApp nextEventMatchingMask: NSAnyEventMask
|
||
untilDate: limit_date
|
||
inMode: NSDefaultRunLoopMode
|
||
dequeue: YES];
|
||
getting_events--;
|
||
|
||
/* We check if last_ufds did not change since the time this function was
|
||
* called. It is possible that a recursive main loop (and thus recursive
|
||
* invocation of this poll function) is triggered while in
|
||
* nextEventMatchingMask:. If during that time new fds are added,
|
||
* the cached fds array might be replaced in g_main_context_iterate().
|
||
* So, we should avoid accessing the old fd array (still pointed at by
|
||
* ufds) here in that case, since it might have been freed. We avoid this
|
||
* by not calling the collect stage.
|
||
*/
|
||
if (last_ufds == ufds && n_ready < 0)
|
||
n_ready = select_thread_collect_poll (ufds, nfds);
|
||
|
||
if (event &&
|
||
[event type] == NSApplicationDefined &&
|
||
[event subtype] == GDK_QUARTZ_EVENT_SUBTYPE_EVENTLOOP)
|
||
{
|
||
/* Just used to wake us up; if an event and a FD arrived at the same
|
||
* time; could have come from a previous iteration in some cases,
|
||
* but the spurious wake up is harmless if a little inefficient.
|
||
*/
|
||
event = NULL;
|
||
}
|
||
|
||
if (event)
|
||
{
|
||
if (!current_events)
|
||
current_events = g_queue_new ();
|
||
g_queue_push_head (current_events, [event retain]);
|
||
}
|
||
|
||
return n_ready;
|
||
}
|
||
|
||
/************************************************************
|
||
********* Running the main loop out of CFRunLoop *********
|
||
************************************************************/
|
||
|
||
/* Wrapper around g_main_context_query() that handles reallocating
|
||
* run_loop_pollfds up to the proper size
|
||
*/
|
||
static gint
|
||
query_main_context (GMainContext *context,
|
||
int max_priority,
|
||
int *timeout)
|
||
{
|
||
gint nfds;
|
||
|
||
if (!run_loop_pollfds)
|
||
{
|
||
run_loop_pollfds_size = RUN_LOOP_POLLFDS_INITIAL_SIZE;
|
||
run_loop_pollfds = g_new (GPollFD, run_loop_pollfds_size);
|
||
}
|
||
|
||
while ((nfds = g_main_context_query (context, max_priority, timeout,
|
||
run_loop_pollfds,
|
||
run_loop_pollfds_size)) > run_loop_pollfds_size)
|
||
{
|
||
g_free (run_loop_pollfds);
|
||
run_loop_pollfds_size = nfds;
|
||
run_loop_pollfds = g_new (GPollFD, nfds);
|
||
}
|
||
|
||
return nfds;
|
||
}
|
||
|
||
static void
|
||
run_loop_entry (void)
|
||
{
|
||
if (acquired_loop_level == -1)
|
||
{
|
||
if (g_main_context_acquire (NULL))
|
||
{
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Beginning tracking run loop activity"));
|
||
acquired_loop_level = current_loop_level;
|
||
}
|
||
else
|
||
{
|
||
/* If we fail to acquire the main context, that means someone is iterating
|
||
* the main context in a different thread; we simply wait until this loop
|
||
* exits and then try again at next entry. In general, iterating the loop
|
||
* from a different thread is rare: it is only possible when GDK threading
|
||
* is initialized and is not frequently used even then. So, we hope that
|
||
* having GLib main loop iteration blocked in the combination of that and
|
||
* a native modal operation is a minimal problem. We could imagine using a
|
||
* thread that does g_main_context_wait() and then wakes us back up, but
|
||
* the gain doesn't seem worth the complexity.
|
||
*/
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Can't acquire main loop; skipping tracking run loop activity"));
|
||
}
|
||
}
|
||
}
|
||
|
||
static void
|
||
run_loop_before_timers (void)
|
||
{
|
||
}
|
||
|
||
static void
|
||
run_loop_before_sources (void)
|
||
{
|
||
GMainContext *context = g_main_context_default ();
|
||
gint max_priority;
|
||
gint nfds;
|
||
|
||
/* Before we let the CFRunLoop process sources, we want to check if there
|
||
* are any pending GLib main loop sources more urgent than
|
||
* G_PRIORITY_DEFAULT that need to be dispatched. (We consider all activity
|
||
* from the CFRunLoop to have a priority of G_PRIORITY_DEFAULT.) If no
|
||
* sources are processed by the CFRunLoop, then processing will continue
|
||
* on to the BeforeWaiting stage where we check for lower priority sources.
|
||
*/
|
||
|
||
g_main_context_prepare (context, &max_priority);
|
||
max_priority = MIN (max_priority, G_PRIORITY_DEFAULT);
|
||
|
||
/* We ignore the timeout that query_main_context () returns since we'll
|
||
* always query again before waiting.
|
||
*/
|
||
nfds = query_main_context (context, max_priority, NULL);
|
||
|
||
if (nfds)
|
||
old_poll_func (run_loop_pollfds, nfds, 0);
|
||
|
||
if (g_main_context_check (context, max_priority, run_loop_pollfds, nfds))
|
||
{
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Dispatching high priority sources"));
|
||
g_main_context_dispatch (context);
|
||
}
|
||
}
|
||
|
||
static void
|
||
dummy_timer_callback (CFRunLoopTimerRef timer,
|
||
void *info)
|
||
{
|
||
/* Nothing; won't normally even be called */
|
||
}
|
||
|
||
static void
|
||
run_loop_before_waiting (void)
|
||
{
|
||
GMainContext *context = g_main_context_default ();
|
||
gint timeout;
|
||
gint n_ready;
|
||
|
||
/* At this point, the CFRunLoop is ready to wait. We start a GMain loop
|
||
* iteration by calling the check() and query() stages. We start a
|
||
* poll, and if it doesn't complete immediately we let the run loop
|
||
* go ahead and sleep. Before doing that, if there was a timeout from
|
||
* GLib, we set up a CFRunLoopTimer to wake us up.
|
||
*/
|
||
|
||
g_main_context_prepare (context, &run_loop_max_priority);
|
||
|
||
run_loop_n_pollfds = query_main_context (context, run_loop_max_priority, &timeout);
|
||
|
||
n_ready = select_thread_start_poll (run_loop_pollfds, run_loop_n_pollfds, timeout);
|
||
|
||
if (n_ready > 0 || timeout == 0)
|
||
{
|
||
/* We have stuff to do, no sleeping allowed! */
|
||
CFRunLoopWakeUp (main_thread_run_loop);
|
||
}
|
||
else if (timeout > 0)
|
||
{
|
||
/* We need to get the run loop to break out of its wait when our timeout
|
||
* expires. We do this by adding a dummy timer that we'll remove immediately
|
||
* after the wait wakes up.
|
||
*/
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Adding timer to wake us up in %d milliseconds", timeout));
|
||
|
||
run_loop_timer = CFRunLoopTimerCreate (NULL, /* allocator */
|
||
CFAbsoluteTimeGetCurrent () + timeout / 1000.,
|
||
0, /* interval (0=does not repeat) */
|
||
0, /* flags */
|
||
0, /* order (priority) */
|
||
dummy_timer_callback,
|
||
NULL);
|
||
|
||
CFRunLoopAddTimer (main_thread_run_loop, run_loop_timer, kCFRunLoopCommonModes);
|
||
}
|
||
|
||
run_loop_polling_async = n_ready < 0;
|
||
}
|
||
|
||
static void
|
||
run_loop_after_waiting (void)
|
||
{
|
||
GMainContext *context = g_main_context_default ();
|
||
|
||
/* After sleeping, we finish of the GMain loop iteratin started in before_waiting()
|
||
* by doing the check() and dispatch() stages.
|
||
*/
|
||
|
||
if (run_loop_timer)
|
||
{
|
||
CFRunLoopRemoveTimer (main_thread_run_loop, run_loop_timer, kCFRunLoopCommonModes);
|
||
CFRelease (run_loop_timer);
|
||
run_loop_timer = NULL;
|
||
}
|
||
|
||
if (run_loop_polling_async)
|
||
{
|
||
select_thread_collect_poll (run_loop_pollfds, run_loop_n_pollfds);
|
||
run_loop_polling_async = FALSE;
|
||
}
|
||
|
||
if (g_main_context_check (context, run_loop_max_priority, run_loop_pollfds, run_loop_n_pollfds))
|
||
{
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Dispatching after waiting"));
|
||
g_main_context_dispatch (context);
|
||
}
|
||
}
|
||
|
||
static void
|
||
run_loop_exit (void)
|
||
{
|
||
/* + 1 because we decrement current_loop_level separately in observer_callback() */
|
||
if ((current_loop_level + 1) == acquired_loop_level)
|
||
{
|
||
g_main_context_release (NULL);
|
||
acquired_loop_level = -1;
|
||
GDK_NOTE (EVENTLOOP, g_message ("EventLoop: Ended tracking run loop activity"));
|
||
}
|
||
}
|
||
|
||
static void
|
||
run_loop_observer_callback (CFRunLoopObserverRef observer,
|
||
CFRunLoopActivity activity,
|
||
void *info)
|
||
{
|
||
switch (activity)
|
||
{
|
||
case kCFRunLoopEntry:
|
||
current_loop_level++;
|
||
break;
|
||
case kCFRunLoopExit:
|
||
g_return_if_fail (current_loop_level > 0);
|
||
current_loop_level--;
|
||
break;
|
||
default:
|
||
break;
|
||
}
|
||
|
||
if (getting_events > 0) /* Activity we triggered */
|
||
return;
|
||
|
||
switch (activity)
|
||
{
|
||
case kCFRunLoopEntry:
|
||
run_loop_entry ();
|
||
break;
|
||
case kCFRunLoopBeforeTimers:
|
||
run_loop_before_timers ();
|
||
break;
|
||
case kCFRunLoopBeforeSources:
|
||
run_loop_before_sources ();
|
||
break;
|
||
case kCFRunLoopBeforeWaiting:
|
||
run_loop_before_waiting ();
|
||
break;
|
||
case kCFRunLoopAfterWaiting:
|
||
run_loop_after_waiting ();
|
||
break;
|
||
case kCFRunLoopExit:
|
||
run_loop_exit ();
|
||
break;
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
|
||
/************************************************************/
|
||
|
||
void
|
||
_gdk_quartz_event_loop_init (void)
|
||
{
|
||
GSource *source;
|
||
CFRunLoopObserverRef observer;
|
||
|
||
/* Hook into the GLib main loop */
|
||
|
||
event_poll_fd.events = G_IO_IN;
|
||
event_poll_fd.fd = -1;
|
||
|
||
source = g_source_new (&event_funcs, sizeof (GSource));
|
||
g_source_set_name (source, "GDK Quartz event source");
|
||
g_source_add_poll (source, &event_poll_fd);
|
||
g_source_set_priority (source, GDK_PRIORITY_EVENTS);
|
||
g_source_set_can_recurse (source, TRUE);
|
||
g_source_attach (source, NULL);
|
||
|
||
old_poll_func = g_main_context_get_poll_func (NULL);
|
||
g_main_context_set_poll_func (NULL, poll_func);
|
||
|
||
/* Hook into the the CFRunLoop for the main thread */
|
||
|
||
main_thread_run_loop = CFRunLoopGetCurrent ();
|
||
|
||
observer = CFRunLoopObserverCreate (NULL, /* default allocator */
|
||
kCFRunLoopAllActivities,
|
||
true, /* repeats: not one-shot */
|
||
0, /* order (priority) */
|
||
run_loop_observer_callback,
|
||
NULL);
|
||
|
||
CFRunLoopAddObserver (main_thread_run_loop, observer, kCFRunLoopCommonModes);
|
||
|
||
/* Initialize our autorelease pool */
|
||
|
||
autorelease_pool = [[NSAutoreleasePool alloc] init];
|
||
}
|