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* src/xterm.c (xi_populate_device_from_info): Take dpyinfo.
Describe what master and slave devices are, how they represent
seats, and how they are used to multiplex user input.  Also
simplify ifdefs and avoid looping over scroll classes on XI 2.0.
(x_cache_xi_devices, handle_one_xevent): Adjust accordingly.
(x_term_init): Set dpyinfo->xi2_version before calling
x_cache_xi_devices.
This commit is contained in:
Po Lu 2022-11-06 19:37:02 +08:00
parent cd296e19a2
commit f305d1ab3a
1 changed files with 73 additions and 13 deletions
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86
src/xterm.c
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@ -5317,7 +5317,8 @@ struct xi_known_valuator
#endif
static void
xi_populate_device_from_info (struct xi_device_t *xi_device,
xi_populate_device_from_info (struct x_display_info *dpyinfo,
struct xi_device_t *xi_device,
XIDeviceInfo *device)
{
#ifdef HAVE_XINPUT2_1
@ -5335,26 +5336,85 @@ xi_populate_device_from_info (struct xi_device_t *xi_device,
USE_SAFE_ALLOCA;
#endif
/* Initialize generic information about the device: its ID, which
buttons are currently pressed and thus presumably actively
grabbing the device, what kind of device it is (master pointer,
master keyboard, slave pointer, slave keyboard, or floating
slave), and its attachment.
Here is a brief description of what device uses and attachments
are. Under XInput 2, user input from individual input devices is
multiplexed into specific seats before being delivered, with each
seat corresponding to a single on-screen mouse pointer and having
its own keyboard focus. Each seat consists of two virtual
devices: the master keyboard and the master pointer, the first of
which is used to report all keyboard input, with the other used
to report all other input.
Input from each physical device (mouse, trackpad or keyboard) is
then associated with that slave device's paired master device.
For example, moving the device "Logitech USB Optical Mouse",
enslaved by the master pointer device "Virtual core pointer",
will result in movement of the mouse pointer associated with that
master device's seat. If the pointer moves over an Emacs frame,
then the frame will receive XI_Enter and XI_Motion events from
that master pointer.
Likewise, keyboard input from the device "AT Translated Set 2
keyboard", enslaved by the master keyboard device "Virtual core
keyboard", will be reported to its seat's input focus window.
The device use describes what the device is. The meanings of
MasterPointer, MasterKeyboard, SlavePointer and SlaveKeyboard
should be obvious. FloatingSlave means the device is a slave
device that is not associated with any seat, and thus generates
no input.
The device attachment is a device ID whose meaning varies
depending on the device use. If the device is a master device,
then the attachment is the device ID of the other device in its
seat (the master keyboard for master pointer devices, and vice
versa). Otherwise, it is the ID of the master device the slave
device is attached to. For slave devices not attached to any
seat, its value is undefined. */
xi_device->device_id = device->deviceid;
xi_device->grab = 0;
#ifdef HAVE_XINPUT2_1
actual_valuator_count = 0;
xi_device->valuators = xnmalloc (device->num_classes,
sizeof *xi_device->valuators);
values = NULL;
#endif
xi_device->use = device->use;
xi_device->name = build_string (device->name);
xi_device->attachment = device->attachment;
/* Clear the list of active touch points on the device, which are
individual touches tracked by a touchscreen. */
#ifdef HAVE_XINPUT2_2
xi_device->touchpoints = NULL;
xi_device->direct_p = false;
#endif
#ifdef HAVE_XINPUT2_1
if (!dpyinfo->xi2_version)
{
/* Skip everything below as there are no classes of interest on
XI 2.0 servers. */
xi_device->valuators = NULL;
xi_device->scroll_valuator_count = 0;
return;
}
actual_valuator_count = 0;
xi_device->valuators = xnmalloc (device->num_classes,
sizeof *xi_device->valuators);
values = NULL;
/* Initialize device info based on a list of "device classes".
Device classes are little pieces of information associated with a
device. Emacs is interested in scroll valuator information and
touch handling information, which respectively describe the axes
(if any) along which the device's scroll wheel rotates, and how
the device reports touch input. */
for (c = 0; c < device->num_classes; ++c)
{
switch (device->classes[c]->type)
@ -5474,7 +5534,8 @@ x_cache_xi_devices (struct x_display_info *dpyinfo)
for (i = 0; i < ndevices; ++i)
{
if (infos[i].enabled)
xi_populate_device_from_info (&dpyinfo->devices[actual_devices++],
xi_populate_device_from_info (dpyinfo,
&dpyinfo->devices[actual_devices++],
&infos[i]);
}
@ -23607,7 +23668,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
memset (dpyinfo->devices + dpyinfo->num_devices - 1,
0, sizeof *dpyinfo->devices);
device = &dpyinfo->devices[dpyinfo->num_devices - 1];
xi_populate_device_from_info (device, info);
xi_populate_device_from_info (dpyinfo, device, info);
}
if (info)
@ -29608,11 +29669,10 @@ x_term_init (Lisp_Object display_name, char *xrm_option, char *resource_name)
xi_select_hierarchy_events (dpyinfo);
#endif
dpyinfo->xi2_version = minor;
x_cache_xi_devices (dpyinfo);
}
}
dpyinfo->xi2_version = minor;
skip_xi_setup:
;
#endif