Implement the INCR ICCCM selection mechanism

xcb_get_property is now also called with a length that is a multiple
of four so that we advance the offset properly.

Some cleanup.

Selection code should work pretty well by now.  The amount of code
supporting it has more than doubled since GTK+.
This commit is contained in:
Přemysl Eric Janouch 2018-09-23 06:38:32 +02:00
parent 86417d512b
commit 2efaed1a56
Signed by: p
GPG Key ID: A0420B94F92B9493

View File

@ -1833,8 +1833,13 @@ struct selection_watch
guint watch; ///< X11 connection watcher
xcb_window_t wid; ///< Withdrawn communications window
xcb_atom_t atom_incr; ///< INCR
xcb_atom_t atom_utf8_string; ///< UTF8_STRING
xcb_timestamp_t in_progress; ///< Timestamp of last processed event
GString * buffer; ///< UTF-8 text buffer
gboolean incr; ///< INCR running
gboolean incr_failure; ///< INCR failure indicator
};
static gboolean
@ -1877,85 +1882,145 @@ on_selection_text_received (SelectionWatch *self, const gchar *text)
static gboolean
read_utf8_property (SelectionWatch *self, xcb_window_t wid, xcb_atom_t property,
GString *buf)
gboolean *empty)
{
guint32 offset = 0;
gboolean loop = TRUE, ok = TRUE;
while (ok && loop)
gboolean more_data = TRUE, ok = TRUE;
xcb_get_property_reply_t *gpr;
while (ok && more_data)
{
xcb_get_property_reply_t *gpr = xcb_get_property_reply (self->X,
if (!(gpr = xcb_get_property_reply (self->X,
xcb_get_property (self->X, FALSE /* delete */, wid,
property, XCB_GET_PROPERTY_TYPE_ANY, offset, 0x7fff), NULL);
property, XCB_GET_PROPERTY_TYPE_ANY, offset, 0x8000), NULL)))
return FALSE;
if (!gpr || gpr->type != self->atom_utf8_string || gpr->format != 8)
ok = FALSE;
else
int len = xcb_get_property_value_length (gpr);
if (offset == 0 && len == 0 && empty)
*empty = TRUE;
ok = gpr->type == self->atom_utf8_string && gpr->format == 8;
more_data = gpr->bytes_after != 0;
if (ok)
{
int len = xcb_get_property_value_length (gpr);
g_string_append_len (buf, xcb_get_property_value (gpr), len);
offset += len >> 2;
loop = gpr->bytes_after > 0;
g_string_append_len (self->buffer,
xcb_get_property_value (gpr), len);
}
free (gpr);
}
return ok;
}
static void
on_x11_selection_change (SelectionWatch *self,
xcb_xfixes_selection_notify_event_t *e)
{
// Not checking whether we should give up when this interrupts our
// current retrieval attempt--the timeout mostly solves this for all cases
if (e->owner == XCB_NONE)
return;
// Don't try to process two things at once. Each request gets a few seconds
// to finish, then we move on, hoping that a property race doesn't commence.
// Ideally we'd set up a separate queue for these skipped requests and
// process them later.
if (self->in_progress != 0 && e->timestamp - self->in_progress < 5000)
return;
// ICCCM says we should ensure the named property doesn't exist
(void) xcb_delete_property (self->X, self->wid, XCB_ATOM_PRIMARY);
(void) xcb_convert_selection (self->X, self->wid, e->selection,
self->atom_utf8_string, XCB_ATOM_PRIMARY, e->timestamp);
self->in_progress = e->timestamp;
self->incr = FALSE;
}
static void
on_x11_selection_receive (SelectionWatch *self,
xcb_selection_notify_event_t *e)
{
if (e->requestor != self->wid
|| e->time != self->in_progress)
return;
self->in_progress = 0;
if (e->property == XCB_ATOM_NONE)
return;
xcb_get_property_reply_t *gpr = xcb_get_property_reply (self->X,
xcb_get_property (self->X, FALSE /* delete */, e->requestor,
e->property, XCB_GET_PROPERTY_TYPE_ANY, 0, 0), NULL);
if (!gpr)
return;
// Garbage collection, GString only ever expands in size
g_string_free (self->buffer, TRUE);
self->buffer = g_string_new (NULL);
// When you select a lot of text in VIM, it starts the ICCCM INCR mechanism,
// from which there is no opt-out
if (gpr->type == self->atom_incr)
{
self->in_progress = e->time;
self->incr = TRUE;
self->incr_failure = FALSE;
}
else if (read_utf8_property (self, e->requestor, e->property, NULL))
on_selection_text_received (self, self->buffer->str);
free (gpr);
(void) xcb_delete_property (self->X, self->wid, e->property);
}
static void
on_x11_property_notify (SelectionWatch *self, xcb_property_notify_event_t *e)
{
if (!self->incr
|| e->window != self->wid
|| e->state != XCB_PROPERTY_NEW_VALUE
|| e->atom != XCB_ATOM_PRIMARY)
return;
gboolean empty = FALSE;
if (!read_utf8_property (self, e->window, e->atom, &empty))
// We need to keep deleting the property
self->incr_failure = TRUE;
// Once it's empty, we've consumed everything and can move on undisturbed
if (empty)
{
if (!self->incr_failure)
on_selection_text_received (self, self->buffer->str);
self->in_progress = 0;
self->incr = FALSE;
}
(void) xcb_delete_property (self->X, e->window, e->atom);
}
static void
process_x11_event (SelectionWatch *self, xcb_generic_event_t *event)
{
xcb_generic_error_t *err = NULL;
int event_code = event->response_type & 0x7f;
if (event_code == 0)
{
err = (xcb_generic_error_t *) event;
xcb_generic_error_t *err = (xcb_generic_error_t *) event;
g_warning (_("X11 request error (%d, major %d, minor %d)"),
err->error_code, err->major_code, err->minor_code);
}
else if (event_code ==
self->xfixes->first_event + XCB_XFIXES_SELECTION_NOTIFY)
{
xcb_xfixes_selection_notify_event_t *e =
(xcb_xfixes_selection_notify_event_t *) event;
// Not checking whether we should give up when this interrupts our
// current retrieval attempt--the timeout solves this
if (e->owner == XCB_NONE)
return;
// Don't try to process two things at once. Each request gets a few
// seconds to finish, then we move on, hoping that a property race
// doesn't commence. Ideally we'd set up a separate queue for these
// skipped requests and process them later.
if (self->in_progress != 0 && e->timestamp - self->in_progress < 5000)
return;
// ICCCM says we should ensure the named property doesn't exist
(void) xcb_delete_property (self->X, self->wid, XCB_ATOM_PRIMARY);
(void) xcb_convert_selection (self->X, self->wid, e->selection,
self->atom_utf8_string, XCB_ATOM_PRIMARY, e->timestamp);
self->in_progress = e->timestamp;
}
on_x11_selection_change (self,
(xcb_xfixes_selection_notify_event_t *) event);
else if (event_code == XCB_SELECTION_NOTIFY)
{
xcb_selection_notify_event_t *e =
(xcb_selection_notify_event_t *) event;
if (e->time != self->in_progress)
return;
self->in_progress = 0;
if (e->property == XCB_ATOM_NONE)
return;
GString *buf = g_string_new (NULL);
if (read_utf8_property (self, e->requestor, e->property, buf))
on_selection_text_received (self, buf->str);
g_string_free (buf, TRUE);
(void) xcb_delete_property (self->X, self->wid, e->property);
}
on_x11_selection_receive (self,
(xcb_selection_notify_event_t *) event);
else if (event_code == XCB_PROPERTY_NOTIFY)
on_x11_property_notify (self,
(xcb_property_notify_event_t *) event);
}
static gboolean
@ -1991,6 +2056,8 @@ selection_watch_init (SelectionWatch *self, Application *app)
// fallback might be good to add (COMPOUND_TEXT is complex)
g_return_if_fail
((self->atom_utf8_string = resolve_atom (self->X, "UTF8_STRING")));
g_return_if_fail
((self->atom_incr = resolve_atom (self->X, "INCR")));
self->xfixes = xcb_get_extension_data (self->X, &xcb_xfixes_id);
g_return_if_fail (self->xfixes->present);
@ -2005,9 +2072,10 @@ selection_watch_init (SelectionWatch *self, Application *app)
xcb_screen_t *screen = setup_iter.data;
self->wid = xcb_generate_id (self->X);
const uint32_t values[] = {XCB_EVENT_MASK_PROPERTY_CHANGE};
(void) xcb_create_window (self->X, screen->root_depth, self->wid,
screen->root, 0, 0, 1, 1, 0, XCB_WINDOW_CLASS_INPUT_OUTPUT,
screen->root_visual, 0, NULL);
screen->root_visual, XCB_CW_EVENT_MASK, values);
(void) xcb_xfixes_select_selection_input (self->X, self->wid,
XCB_ATOM_PRIMARY, XCB_XFIXES_SELECTION_EVENT_MASK_SET_SELECTION_OWNER |
@ -2017,6 +2085,9 @@ selection_watch_init (SelectionWatch *self, Application *app)
(void) xcb_flush (self->X);
self->watch = g_io_add_watch (g_io_channel_unix_new
(xcb_get_file_descriptor (self->X)), G_IO_IN, process_x11, self);
// Never NULL so that we don't need to care about pointer validity
self->buffer = g_string_new (NULL);
}
static void
@ -2026,6 +2097,8 @@ selection_watch_destroy (SelectionWatch *self)
xcb_disconnect (self->X);
if (self->watch)
g_source_remove (self->watch);
if (self->buffer)
g_string_free (self->buffer, TRUE);
}
#endif // WITH_X11