master d5499e3eb2: Display caret in preedit text where the input method asked

[Po Lu]

branch: master
commit d5499e3eb2765ddf212e3f21fed7b356b8f0ec76
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Display caret in preedit text where the input method asked
    
    * src/xfns.c (xic_preedit_start_callback): Clear caret position.
    (xic_preedit_caret_callback): Record new caret position and
    announce it.
    (xic_preedit_done_callback): Clear caret position.
    (xic_preedit_draw_callback): Set caret position appropriately.
---
 src/xfns.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/src/xfns.c b/src/xfns.c
index 073200ff75..0254b3d0b1 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -2922,6 +2922,7 @@ xic_preedit_start_callback (XIC xic, XPointer client_data,
 
       output->preedit_size = 0;
       output->preedit_active = true;
+      output->preedit_caret = 0;
 
       if (output->preedit_chars)
        xfree (output->preedit_chars);
@@ -2936,7 +2937,54 @@ static void
 xic_preedit_caret_callback (XIC xic, XPointer client_data,
                            XIMPreeditCaretCallbackStruct *call_data)
 {
+  struct frame *f = x_xic_to_frame (xic);
+  struct x_output *output;
+  struct input_event ie;
+  EVENT_INIT (ie);
+
+  if (f)
+    {
+      output = FRAME_X_OUTPUT (f);
+
+      if (!output->preedit_active)
+       return;
+
+      switch (call_data->direction)
+       {
+       case XIMAbsolutePosition:
+         output->preedit_caret = call_data->position;
+         break;
+       case XIMForwardChar:
+       case XIMForwardWord:
+         call_data->position = output->preedit_caret++;
+         break;
+       case XIMBackwardChar:
+       case XIMBackwardWord:
+         call_data->position = max (0, output->preedit_caret--);
+         break;
+       default:
+         call_data->position = output->preedit_caret;
+       }
+
+      if (output->preedit_chars)
+       {
+         ie.kind = PREEDIT_TEXT_EVENT;
+         XSETFRAME (ie.frame_or_window, f);
+         ie.arg = make_string_from_utf8 (output->preedit_chars,
+                                         output->preedit_size);
+
+         Fput_text_property (make_fixnum (0),
+                             make_fixnum (SCHARS (ie.arg)),
+                             Qcursor,
+                             make_fixnum (output->preedit_caret),
+                             ie.arg);
 
+         XSETINT (ie.x, 0);
+         XSETINT (ie.y, 0);
+
+         kbd_buffer_store_event (&ie);
+       }
+    }
 }
 
 
@@ -2966,6 +3014,7 @@ xic_preedit_done_callback (XIC xic, XPointer client_data,
       output->preedit_size = 0;
       output->preedit_active = false;
       output->preedit_chars = NULL;
+      output->preedit_caret = 0;
     }
 }
 
@@ -3137,6 +3186,8 @@ xic_preedit_draw_callback (XIC xic, XPointer client_data,
       if (text)
        xfree (text);
 
+      output->preedit_caret = call_data->caret;
+
       /* This is okay because this callback is called from the big XIM
         event filter, which runs inside XTread_socket.  */
 
@@ -3144,6 +3195,13 @@ xic_preedit_draw_callback (XIC xic, XPointer client_data,
       XSETFRAME (ie.frame_or_window, f);
       ie.arg = make_string_from_utf8 (output->preedit_chars,
                                      output->preedit_size);
+
+      Fput_text_property (make_fixnum (0),
+                         make_fixnum (SCHARS (ie.arg)),
+                         Qcursor,
+                         make_fixnum (output->preedit_caret),
+                         ie.arg);
+
       XSETINT (ie.x, 0);
       XSETINT (ie.y, 0);
 
@@ -3160,6 +3218,7 @@ xic_preedit_draw_callback (XIC xic, XPointer client_data,
   output->preedit_chars = NULL;
   output->preedit_size = 0;
   output->preedit_active = false;
+  output->preedit_caret = 0;
 }
 
 void