Fix off-by-one errors in caret position application

* src/gtkutil.c (xg_im_context_preedit_changed):
* src/xfns.c (xic_preedit_caret_callback):
(xic_preedit_draw_callback): Constrain caret position to
SCHARS (arg) - 1.

diff --git a/src/gtkutil.c b/src/gtkutil.c
index c47386dae00f1b3b97a3fc9a1ad9dc0b84609441..8eab6ee723d639ed46f2c795696eded3c522ccf5 100644 (file)
--- a/src/gtkutil.c
+++ b/src/gtkutil.c
@@ -6090,11 +6090,12 @@ xg_im_context_preedit_changed (GtkIMContext *imc, gpointer user_data)
   inev.kind = PREEDIT_TEXT_EVENT;
   inev.arg = build_string_from_utf8 (str);
 
-  Fput_text_property (make_fixnum (min (SCHARS (inev.arg),
-                                       max (0, cursor))),
-                     make_fixnum (min (SCHARS (inev.arg),
-                                       max (0, cursor) + 1)),
-                     Qcursor, Qt, inev.arg);
+  if (SCHARS (inev.arg))
+    Fput_text_property (make_fixnum (min (SCHARS (inev.arg) - 1,
+                                         max (0, cursor))),
+                       make_fixnum (min (SCHARS (inev.arg),
+                                         max (0, cursor) + 1)),
+                       Qcursor, Qt, inev.arg);
 
   kbd_buffer_store_event (&inev);
 

diff --git a/src/xfns.c b/src/xfns.c
index 7540816416d81b94197c06d5547f98ad74da0e3d..9cf6f528198c1aade5476b6be80e150b4f57077f 100644 (file)
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -2973,11 +2973,12 @@ xic_preedit_caret_callback (XIC xic, XPointer client_data,
          ie.arg = make_string_from_utf8 (output->preedit_chars,
                                          output->preedit_size);
 
-         Fput_text_property (make_fixnum (min (SCHARS (ie.arg),
-                                               max (0, output->preedit_caret))),
-                             make_fixnum (max (SCHARS (ie.arg),
-                                               max (0, output->preedit_caret) + 1)),
-                             Qcursor, Qt, ie.arg);
+         if (SCHARS (ie.arg))
+           Fput_text_property (make_fixnum (min (SCHARS (ie.arg) - 1,
+                                                 max (0, output->preedit_caret))),
+                               make_fixnum (max (SCHARS (ie.arg),
+                                                 max (0, output->preedit_caret) + 1)),
+                               Qcursor, Qt, ie.arg);
 
          XSETINT (ie.x, 0);
          XSETINT (ie.y, 0);
@@ -3196,11 +3197,12 @@ xic_preedit_draw_callback (XIC xic, XPointer client_data,
       ie.arg = make_string_from_utf8 (output->preedit_chars,
                                      output->preedit_size);
 
-      Fput_text_property (make_fixnum (min (SCHARS (ie.arg),
-                                           max (0, output->preedit_caret))),
-                         make_fixnum (min (SCHARS (ie.arg),
-                                           max (0, output->preedit_caret) + 1)),
-                         Qcursor, Qt, ie.arg);
+      if (SCHARS (ie.arg))
+       Fput_text_property (make_fixnum (min (SCHARS (ie.arg) - 1,
+                                             max (0, output->preedit_caret))),
+                           make_fixnum (min (SCHARS (ie.arg),
+                                             max (0, output->preedit_caret) + 1)),
+                           Qcursor, Qt, ie.arg);
 
       XSETINT (ie.x, 0);
       XSETINT (ie.y, 0);