wayland/text-input: Use byte based offset in delete_surrounding_text

ClutterInputFocus/GtkIMContext uses char based offset for
delete_surrounding, however, text_input_v3 uses byte based offset for
it. Currently only GTK with mutter can work correctly via text_input_v3
because they both forget to convert between char based offset and byte
based offset.

This commit fixes it in mutter by saving committed surrounding text in
MetaWaylandTextInput and converting char based offset to byte based
offset with the UTF-8 encoded surrounding text.

Fixes <https://gitlab.gnome.org/GNOME/mutter/-/issues/2146>.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2712>
This commit is contained in:
Alynx Zhou 2022-11-25 15:48:01 +08:00 committed by Marge Bot
parent 4b8798a800
commit 27bdf0c577

View File

@ -58,6 +58,20 @@ struct _MetaWaylandTextInput
GHashTable *resource_serials;
/* This saves the uncommitted middle state of surrounding text from client
* between `set_surrounding_text` and `commit`, will be cleared after
* committed.
*/
struct
{
char *text;
uint32_t cursor;
uint32_t anchor;
} pending_surrounding;
/* This is the actual committed surrounding text after `commit`, we need this
* to convert between char based offset and byte based offset.
*/
struct
{
char *text;
@ -216,14 +230,32 @@ meta_wayland_text_input_focus_delete_surrounding (ClutterInputFocus *focus,
guint len)
{
MetaWaylandTextInput *text_input;
const char *start, *end;
const char *before, *after;
const char *cursor;
uint32_t before_length;
uint32_t after_length;
struct wl_resource *resource;
/* offset and len are counted by UTF-8 chars, but text_input_v3's lengths are
* counted by bytes, so we convert UTF-8 char offsets to pointers here, this
* needs the surrounding text
*/
text_input = META_WAYLAND_TEXT_INPUT_FOCUS (focus)->text_input;
before_length = ABS (MIN (offset, 0));
after_length = MAX (0, offset + len);
g_warn_if_fail (ABS (offset) <= len);
offset = MIN (offset, 0);
start = text_input->surrounding.text;
end = start + strlen (text_input->surrounding.text);
cursor = start + text_input->surrounding.cursor;
before = g_utf8_offset_to_pointer (cursor, offset);
g_assert (before >= start);
after = g_utf8_offset_to_pointer (cursor, offset + len);
g_assert (after <= end);
before_length = cursor - before;
after_length = after - cursor;
wl_resource_for_each (resource, &text_input->focus_resource_list)
{
@ -468,10 +500,10 @@ text_input_set_surrounding_text (struct wl_client *client,
if (!client_matches_focus (text_input, client))
return;
g_free (text_input->surrounding.text);
text_input->surrounding.text = g_strdup (text);
text_input->surrounding.cursor = cursor;
text_input->surrounding.anchor = anchor;
g_free (text_input->pending_surrounding.text);
text_input->pending_surrounding.text = g_strdup (text);
text_input->pending_surrounding.cursor = cursor;
text_input->pending_surrounding.anchor = anchor;
text_input->pending_state |= META_WAYLAND_PENDING_STATE_SURROUNDING_TEXT;
}
@ -591,7 +623,7 @@ text_input_set_cursor_rectangle (struct wl_client *client,
static void
meta_wayland_text_input_reset (MetaWaylandTextInput *text_input)
{
g_clear_pointer (&text_input->surrounding.text, g_free);
g_clear_pointer (&text_input->pending_surrounding.text, g_free);
text_input->content_type_hint = ZWP_TEXT_INPUT_V3_CONTENT_HINT_NONE;
text_input->content_type_purpose = ZWP_TEXT_INPUT_V3_CONTENT_PURPOSE_NORMAL;
text_input->text_change_cause = ZWP_TEXT_INPUT_V3_CHANGE_CAUSE_INPUT_METHOD;
@ -651,6 +683,12 @@ text_input_commit_state (struct wl_client *client,
if (text_input->pending_state & META_WAYLAND_PENDING_STATE_SURROUNDING_TEXT)
{
/* Save the surrounding text for `delete_surrounding_text`. */
g_free (text_input->surrounding.text);
text_input->surrounding.text = g_steal_pointer (&text_input->pending_surrounding.text);
text_input->surrounding.cursor = text_input->pending_surrounding.cursor;
text_input->surrounding.anchor = text_input->pending_surrounding.anchor;
/* Pass the surrounding text to Clutter to handle it with input method. */
clutter_input_focus_set_surrounding (text_input->input_focus,
text_input->surrounding.text,
text_input->surrounding.cursor,
@ -720,6 +758,7 @@ meta_wayland_text_input_destroy (MetaWaylandTextInput *text_input)
g_object_unref (text_input->input_focus);
g_hash_table_destroy (text_input->resource_serials);
g_clear_pointer (&text_input->preedit.string, g_free);
g_clear_pointer (&text_input->pending_surrounding.text, g_free);
g_clear_pointer (&text_input->surrounding.text, g_free);
g_free (text_input);
}