backends: Add MetaInputMapper

This object takes care of mapping absolute devices to monitors,
to do so it uses 3 heuristics, in this order of preference:
- If a device is known to be builtin, it's assigned to the
  builtin monitor.
- If input device and monitor match sizes (with an error margin
  of 5%)
- If input device name and monitor vendor/product in EDID match
  somehow (from "full", through "partial", to just "vendor")

The most favorable outputs are then assigned to each device, making
sure not to assign two devices of the same kind to the same output.

This object replaces (and is mostly 1:1 with) GsdDeviceMapper in
g-s-d. That object would perform these same heuristics, and let
mutter indirectly know through settings changes. This object allows
doing the same in-process.

3 files changed, 659 insertions, 0 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 6522e27ad..65a021a30 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -136,6 +136,8 @@ libmutter_@LIBMUTTER_API_VERSION@_la_SOURCES =	\
 	backends/meta-idle-monitor-private.h	\
 	backends/meta-idle-monitor-dbus.c	\
 	backends/meta-idle-monitor-dbus.h	\
+	backends/meta-input-mapper.c		\
+	backends/meta-input-mapper-private.h	\
 	backends/meta-input-settings.c		\
 	backends/meta-input-settings-private.h	\
 	backends/meta-logical-monitor.c		\
diff --git a/src/backends/meta-input-mapper-private.h b/src/backends/meta-input-mapper-private.h
new file mode 100644
index 000000000..53bc66b06
--- /dev/null
+++ b/src/backends/meta-input-mapper-private.h
@@ -0,0 +1,40 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+
+/*
+ * Copyright 2018 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Carlos Garnacho <carlosg@gnome.org>
+ */
+
+#ifndef META_INPUT_MAPPER_H
+#define META_INPUT_MAPPER_H
+
+#include <clutter/clutter.h>
+
+#define META_TYPE_INPUT_MAPPER (meta_input_mapper_get_type ())
+
+G_DECLARE_FINAL_TYPE (MetaInputMapper, meta_input_mapper,
+		      META, INPUT_MAPPER, GObject)
+
+MetaInputMapper * meta_input_mapper_new      (void);
+
+void meta_input_mapper_add_device    (MetaInputMapper    *mapper,
+				      ClutterInputDevice *device,
+                                      gboolean            builtin);
+void meta_input_mapper_remove_device (MetaInputMapper    *mapper,
+				      ClutterInputDevice *device);
+
+#endif /* META_INPUT_MAPPER_H */
diff --git a/src/backends/meta-input-mapper.c b/src/backends/meta-input-mapper.c
new file mode 100644
index 000000000..026dacb58
--- /dev/null
+++ b/src/backends/meta-input-mapper.c
@@ -0,0 +1,617 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+/*
+ * Copyright 2018 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Carlos Garnacho <carlosg@gnome.org>
+ */
+
+#include "config.h"
+
+#include "meta-input-mapper-private.h"
+#include "meta-monitor-manager-private.h"
+#include "meta-logical-monitor.h"
+#include "meta-backend-private.h"
+
+#define MAX_SIZE_MATCH_DIFF 0.05
+
+typedef struct _MetaMapperInputInfo MetaMapperInputInfo;
+typedef struct _MetaMapperOutputInfo MetaMapperOutputInfo;
+typedef struct _MappingHelper MappingHelper;
+typedef struct _DeviceCandidates DeviceCandidates;
+
+struct _MetaInputMapper
+{
+  GObject parent_instance;
+  MetaMonitorManager *monitor_manager;
+  ClutterDeviceManager *input_device_manager;
+  GHashTable *input_devices; /* ClutterInputDevice -> MetaMapperInputInfo */
+  GHashTable *output_devices; /* MetaLogicalMonitor -> MetaMapperOutputInfo */
+};
+
+typedef enum {
+  META_INPUT_CAP_TOUCH  = 1 << 0, /* touch device, either touchscreen or tablet */
+  META_INPUT_CAP_STYLUS = 1 << 1, /* tablet pen */
+  META_INPUT_CAP_ERASER = 1 << 2, /* tablet eraser */
+  META_INPUT_CAP_PAD    = 1 << 3, /* pad device, most usually in tablets */
+  META_INPUT_CAP_CURSOR = 1 << 4  /* pointer-like device in tablets */
+} MetaInputCapabilityFlags;
+
+typedef enum {
+  META_MATCH_IS_BUILTIN,   /* Output is builtin, applies mainly to system-integrated devices */
+  META_MATCH_SIZE,         /* Size from input device and output match */
+  META_MATCH_EDID_FULL,    /* Full EDID model match, eg. "Cintiq 12WX" */
+  META_MATCH_EDID_PARTIAL, /* Partial EDID model match, eg. "Cintiq" */
+  META_MATCH_EDID_VENDOR,  /* EDID vendor match, eg. "WAC" for Wacom */
+  N_OUTPUT_MATCHES
+} MetaOutputMatchType;
+
+struct _MetaMapperInputInfo
+{
+  ClutterInputDevice *device;
+  MetaInputMapper *mapper;
+  MetaMapperOutputInfo *output;
+  guint builtin : 1;
+};
+
+struct _MetaMapperOutputInfo
+{
+  MetaLogicalMonitor *logical_monitor;
+  GList *input_devices;
+  MetaInputCapabilityFlags attached_caps;
+};
+
+struct _MappingHelper
+{
+  GArray *device_maps;
+};
+
+struct _DeviceCandidates
+{
+  MetaMapperInputInfo *input;
+
+  MetaMonitor *candidates[N_OUTPUT_MATCHES];
+
+  MetaOutputMatchType best;
+};
+
+enum {
+  DEVICE_MAPPED,
+  N_SIGNALS
+};
+
+static guint signals[N_SIGNALS] = { 0, };
+
+G_DEFINE_TYPE (MetaInputMapper, meta_input_mapper, G_TYPE_OBJECT)
+
+static MetaMapperInputInfo *
+mapper_input_info_new (ClutterInputDevice *device,
+                       MetaInputMapper    *mapper,
+                       gboolean            builtin)
+{
+  MetaMapperInputInfo *info;
+
+  info = g_new0 (MetaMapperInputInfo, 1);
+  info->mapper = mapper;
+  info->device = device;
+  info->builtin = builtin;
+
+  return info;
+}
+
+static void
+mapper_input_info_free (MetaMapperInputInfo *info)
+{
+  g_free (info);
+}
+
+static MetaMapperOutputInfo *
+mapper_output_info_new (MetaLogicalMonitor *logical_monitor)
+{
+  MetaMapperOutputInfo *info;
+
+  info = g_new0 (MetaMapperOutputInfo, 1);
+  info->logical_monitor = logical_monitor;
+
+  return info;
+}
+
+static void
+mapper_output_info_free (MetaMapperOutputInfo *info)
+{
+  g_free (info);
+}
+
+static MetaInputCapabilityFlags
+mapper_input_info_get_caps (MetaMapperInputInfo *info)
+{
+  ClutterInputDeviceType type;
+
+  type = clutter_input_device_get_device_type (info->device);
+
+  switch (type)
+    {
+    case CLUTTER_TOUCHSCREEN_DEVICE:
+      return META_INPUT_CAP_TOUCH;
+    case CLUTTER_TABLET_DEVICE:
+    case CLUTTER_PEN_DEVICE:
+      return META_INPUT_CAP_STYLUS;
+    case CLUTTER_ERASER_DEVICE:
+      return META_INPUT_CAP_ERASER;
+    case CLUTTER_CURSOR_DEVICE:
+      return META_INPUT_CAP_CURSOR;
+    case CLUTTER_PAD_DEVICE:
+      return META_INPUT_CAP_PAD;
+    default:
+      return 0;
+    }
+}
+
+static void
+mapper_input_info_set_output (MetaMapperInputInfo  *input,
+                              MetaMapperOutputInfo *output,
+                              MetaMonitor          *monitor)
+{
+  if (input->output == output)
+    return;
+
+  input->output = output;
+  g_signal_emit (input->mapper, signals[DEVICE_MAPPED], 0,
+                 input->device,
+                 output ? output->logical_monitor : NULL, monitor);
+}
+
+static void
+mapper_output_info_add_input (MetaMapperOutputInfo *output,
+                              MetaMapperInputInfo  *input,
+                              MetaMonitor          *monitor)
+{
+  g_assert (input->output == NULL);
+
+  output->input_devices = g_list_prepend (output->input_devices, input);
+  output->attached_caps |= mapper_input_info_get_caps (input);
+
+  mapper_input_info_set_output (input, output, monitor);
+}
+
+static void
+mapper_output_info_remove_input (MetaMapperOutputInfo *output,
+                                 MetaMapperInputInfo  *input)
+{
+  GList *l;
+
+  g_assert (input->output == output);
+
+  output->input_devices = g_list_remove (output->input_devices, input);
+  output->attached_caps = 0;
+
+  for (l = output->input_devices; l; l = l->next)
+    output->attached_caps |= mapper_input_info_get_caps (l->data);
+
+  mapper_input_info_set_output (input, NULL, NULL);
+}
+
+static void
+mapper_output_info_clear_inputs (MetaMapperOutputInfo *output)
+{
+  while (output->input_devices)
+    {
+      MetaMapperInputInfo *input = output->input_devices->data;
+
+      mapper_input_info_set_output (input, NULL, NULL);
+      output->input_devices = g_list_remove (output->input_devices, input);
+    }
+
+  output->attached_caps = 0;
+}
+
+static void
+mapping_helper_init (MappingHelper *helper)
+{
+  helper->device_maps = g_array_new (FALSE, FALSE, sizeof (DeviceCandidates));
+}
+
+static void
+mapping_helper_release (MappingHelper *helper)
+{
+  g_array_unref (helper->device_maps);
+}
+
+static gboolean
+match_edid (MetaMapperInputInfo  *input,
+            MetaMonitor          *monitor,
+            MetaOutputMatchType  *match_type)
+{
+  const gchar *dev_name;
+
+  dev_name = clutter_input_device_get_device_name (input->device);
+
+  if (strcasestr (dev_name, meta_monitor_get_vendor (monitor)) == NULL)
+    return FALSE;
+
+  *match_type = META_MATCH_EDID_VENDOR;
+
+  if (strcasestr (dev_name, meta_monitor_get_product (monitor)) != NULL)
+    {
+      *match_type = META_MATCH_EDID_FULL;
+    }
+  else
+    {
+      char **split;
+      int i = 0;
+
+      split = g_strsplit (meta_monitor_get_product (monitor), " ", -1);
+
+      while (split[i])
+        {
+          if (strcasestr (dev_name, split[i]) != NULL)
+            {
+              *match_type = META_MATCH_EDID_PARTIAL;
+              break;
+            }
+        }
+
+      g_strfreev (split);
+    }
+
+  return TRUE;
+}
+
+static gboolean
+find_size_match (MetaMapperInputInfo  *input,
+                 GList                *monitors,
+                 MetaMonitor         **matched_monitor)
+{
+  double min_w_diff, min_h_diff;
+  double i_width, i_height;
+  gboolean found = FALSE;
+  GList *l;
+
+  min_w_diff = min_h_diff = MAX_SIZE_MATCH_DIFF;
+
+  if (!clutter_input_device_get_physical_size (input->device, &i_width, &i_height))
+    return FALSE;
+
+  for (l = monitors; l; l = l->next)
+    {
+      MetaMonitor *monitor = l->data;
+      double w_diff, h_diff;
+      int o_width, o_height;
+
+      meta_monitor_get_physical_dimensions (monitor, &o_width, &o_height);
+      w_diff = ABS (1 - ((double) o_width / i_width));
+      h_diff = ABS (1 - ((double) o_height / i_height));
+
+      if (w_diff >= min_w_diff || h_diff >= min_h_diff)
+        continue;
+
+      *matched_monitor = monitor;
+      min_w_diff = w_diff;
+      min_h_diff = h_diff;
+      found = TRUE;
+    }
+
+  return found;
+}
+
+static gboolean
+find_builtin_output (MetaInputMapper  *mapper,
+                     MetaMonitor     **matched_monitor)
+{
+  MetaMonitor *panel;
+
+  panel = meta_monitor_manager_get_laptop_panel (mapper->monitor_manager);
+  *matched_monitor = panel;
+  return panel != NULL;
+}
+
+static gboolean
+guess_candidates (MetaInputMapper     *mapper,
+                  MetaMapperInputInfo *input,
+                  DeviceCandidates    *info)
+{
+  MetaOutputMatchType best = N_OUTPUT_MATCHES;
+  GList *monitors, *l;
+  MetaMonitor *matched_monitor = NULL;
+
+  monitors = meta_monitor_manager_get_monitors (mapper->monitor_manager);
+
+  for (l = monitors; l; l = l->next)
+    {
+      MetaOutputMatchType edid_match;
+
+      if (match_edid (input, l->data, &edid_match))
+        {
+          best = MIN (best, edid_match);
+          info->candidates[edid_match] = l->data;
+        }
+    }
+
+  if (find_size_match (input, monitors, &matched_monitor))
+    {
+      best = MIN (best, META_MATCH_SIZE);
+      info->candidates[META_MATCH_SIZE] = matched_monitor;
+    }
+
+  if (input->builtin)
+    {
+      best = MIN (best, META_MATCH_IS_BUILTIN);
+      find_builtin_output (mapper, &info->candidates[META_MATCH_IS_BUILTIN]);
+    }
+
+  if (best < N_OUTPUT_MATCHES)
+    {
+      info->best = best;
+      return TRUE;
+    }
+  else
+    {
+      return FALSE;
+    }
+}
+
+static void
+mapping_helper_add (MappingHelper       *helper,
+		    MetaMapperInputInfo *input,
+                    MetaInputMapper     *mapper)
+{
+  DeviceCandidates info = { 0, };
+  guint i, pos = 0;
+
+  info.input = input;
+
+  if (!guess_candidates (mapper, input, &info))
+    return;
+
+  for (i = 0; i < helper->device_maps->len; i++)
+    {
+      DeviceCandidates *elem;
+
+      elem = &g_array_index (helper->device_maps, DeviceCandidates, i);
+
+      if (elem->best < info.best)
+        pos = i;
+    }
+
+  if (pos >= helper->device_maps->len)
+    g_array_append_val (helper->device_maps, info);
+  else
+    g_array_insert_val (helper->device_maps, pos, info);
+}
+
+static void
+mapping_helper_apply (MappingHelper   *helper,
+                      MetaInputMapper *mapper)
+{
+  guint i;
+
+  /* Now, decide which input claims which output */
+  for (i = 0; i < helper->device_maps->len; i++)
+    {
+      MetaMapperOutputInfo *output;
+      DeviceCandidates *info;
+      MetaOutputMatchType j;
+
+      info = &g_array_index (helper->device_maps, DeviceCandidates, i);
+
+      for (j = 0; j < N_OUTPUT_MATCHES; j++)
+        {
+          MetaLogicalMonitor *logical_monitor;
+
+          if (!info->candidates[j])
+            continue;
+
+          logical_monitor =
+            meta_monitor_get_logical_monitor (info->candidates[j]);
+          output = g_hash_table_lookup (mapper->output_devices,
+                                        logical_monitor);
+
+          if (!output)
+            continue;
+
+          if (output->attached_caps & mapper_input_info_get_caps (info->input))
+            continue;
+
+          mapper_output_info_add_input (output, info->input,
+                                        info->candidates[j]);
+          break;
+        }
+    }
+}
+
+static void
+mapper_recalculate_candidates (MetaInputMapper *mapper)
+{
+  MetaMapperInputInfo *input;
+  MappingHelper helper;
+  GHashTableIter iter;
+
+  mapping_helper_init (&helper);
+  g_hash_table_iter_init (&iter, mapper->input_devices);
+
+  while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &input))
+    mapping_helper_add (&helper, input, mapper);
+
+  mapping_helper_apply (&helper, mapper);
+  mapping_helper_release (&helper);
+}
+
+static void
+mapper_recalculate_input (MetaInputMapper     *mapper,
+                          MetaMapperInputInfo *input)
+{
+  MappingHelper helper;
+
+  mapping_helper_init (&helper);
+  mapping_helper_add (&helper, input, mapper);
+  mapping_helper_apply (&helper, mapper);
+  mapping_helper_release (&helper);
+}
+
+static void
+mapper_update_outputs (MetaInputMapper *mapper)
+{
+  MetaMapperOutputInfo *output;
+  GList *logical_monitors, *l;
+  GHashTableIter iter;
+
+  g_hash_table_iter_init (&iter, mapper->output_devices);
+
+  while (g_hash_table_iter_next (&iter, NULL, (gpointer *) &output))
+    {
+      mapper_output_info_clear_inputs (output);
+      g_hash_table_iter_remove (&iter);
+    }
+
+  logical_monitors =
+    meta_monitor_manager_get_logical_monitors (mapper->monitor_manager);
+
+  for (l = logical_monitors; l; l = l->next)
+    {
+      MetaLogicalMonitor *logical_monitor = l->data;
+      MetaMapperOutputInfo *info;
+
+      info = mapper_output_info_new (logical_monitor);
+      g_hash_table_insert (mapper->output_devices, logical_monitor, info);
+    }
+
+  mapper_recalculate_candidates (mapper);
+}
+
+static void
+input_mapper_monitors_changed_cb (MetaMonitorManager *monitor_manager,
+                                  MetaInputMapper    *mapper)
+{
+  mapper_update_outputs (mapper);
+}
+
+static void
+input_mapper_device_removed_cb (ClutterDeviceManager *device_manager,
+                                ClutterInputDevice   *device,
+                                MetaInputMapper      *mapper)
+{
+  meta_input_mapper_remove_device (mapper, device);
+}
+
+static void
+meta_input_mapper_finalize (GObject *object)
+{
+  MetaInputMapper *mapper = META_INPUT_MAPPER (object);
+
+  g_signal_handlers_disconnect_by_func (mapper->monitor_manager,
+                                        input_mapper_monitors_changed_cb,
+                                        mapper);
+  g_signal_handlers_disconnect_by_func (mapper->input_device_manager,
+                                        input_mapper_device_removed_cb,
+                                        mapper);
+
+  g_hash_table_unref (mapper->input_devices);
+  g_hash_table_unref (mapper->output_devices);
+
+  G_OBJECT_CLASS (meta_input_mapper_parent_class)->finalize (object);
+}
+
+static void
+meta_input_mapper_constructed (GObject *object)
+{
+  MetaInputMapper *mapper = META_INPUT_MAPPER (object);
+  MetaBackend *backend;
+
+  G_OBJECT_CLASS (meta_input_mapper_parent_class)->constructed (object);
+
+  mapper->input_device_manager = clutter_device_manager_get_default ();
+  g_signal_connect (mapper->input_device_manager, "device-removed",
+                    G_CALLBACK (input_mapper_device_removed_cb), mapper);
+
+  backend = meta_get_backend ();
+  mapper->monitor_manager = meta_backend_get_monitor_manager (backend);
+  g_signal_connect (mapper->monitor_manager, "monitors-changed-internal",
+                    G_CALLBACK (input_mapper_monitors_changed_cb), mapper);
+
+  mapper_update_outputs (mapper);
+}
+
+static void
+meta_input_mapper_class_init (MetaInputMapperClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->constructed = meta_input_mapper_constructed;
+  object_class->finalize = meta_input_mapper_finalize;
+
+  signals[DEVICE_MAPPED] =
+    g_signal_new ("device-mapped",
+                  G_TYPE_FROM_CLASS (object_class),
+                  G_SIGNAL_RUN_LAST,
+                  0,
+                  NULL, NULL, NULL,
+                  G_TYPE_NONE, 3,
+                  CLUTTER_TYPE_INPUT_DEVICE,
+                  G_TYPE_POINTER, G_TYPE_POINTER);
+}
+
+static void
+meta_input_mapper_init (MetaInputMapper *mapper)
+{
+  mapper->input_devices =
+    g_hash_table_new_full (NULL, NULL, NULL,
+                           (GDestroyNotify) mapper_input_info_free);
+  mapper->output_devices =
+    g_hash_table_new_full (NULL, NULL, NULL,
+                           (GDestroyNotify) mapper_output_info_free);
+}
+
+MetaInputMapper *
+meta_input_mapper_new (void)
+{
+  return g_object_new (META_TYPE_INPUT_MAPPER, NULL);
+}
+
+void
+meta_input_mapper_add_device (MetaInputMapper    *mapper,
+                              ClutterInputDevice *device,
+                              gboolean            builtin)
+{
+  MetaMapperInputInfo *info;
+
+  g_return_if_fail (mapper != NULL);
+  g_return_if_fail (device != NULL);
+
+  if (g_hash_table_contains (mapper->input_devices, device))
+    return;
+
+  info = mapper_input_info_new (device, mapper, builtin);
+  g_hash_table_insert (mapper->input_devices, device, info);
+  mapper_recalculate_input (mapper, info);
+}
+
+void
+meta_input_mapper_remove_device (MetaInputMapper    *mapper,
+                                 ClutterInputDevice *device)
+{
+  MetaMapperInputInfo *input;
+
+  g_return_if_fail (mapper != NULL);
+  g_return_if_fail (device != NULL);
+
+  input = g_hash_table_lookup (mapper->input_devices, device);
+
+  if (input)
+    {
+      if (input->output)
+        mapper_output_info_remove_input (input->output, input);
+      g_hash_table_remove (mapper->input_devices, device);
+    }
+}