Wayland: add support of recoded UTF8 text in clipboard.

1 files changed, 34 insertions, 1 deletions

diff --git a/src/drivers/Wayland/fl_wayland_clipboard_dnd.cxx b/src/drivers/Wayland/fl_wayland_clipboard_dnd.cxx
index 085f2d5b1..8ded06045 100644
--- a/src/drivers/Wayland/fl_wayland_clipboard_dnd.cxx
+++ b/src/drivers/Wayland/fl_wayland_clipboard_dnd.cxx
@@ -1,7 +1,7 @@
 //
 // Wayland-specific code for clipboard and drag-n-drop support.
 //
-// Copyright 1998-2024 by Bill Spitzak and others.
+// Copyright 1998-2026 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -431,6 +431,39 @@ way_out:
     fl_selection_length[1] = strlen(fl_selection_buffer[1]);
   }
   Fl::e_clipboard_type = Fl::clipboard_plain_text;
+  /*
+   UTF8 text from clipboard may encode non-ASCII codepoints as in these examples
+   U+1F431 --> UTF8: 0xF0,0x9F,0x90,0xB1 --> encoded "\F0\9F\90\B1"
+   U+A1 --> UTF8: 0xC2, 0xA1 --> encoded "\C2\A1"
+   Whereas ASCII characters are not encoded.
+   The following decodes that to restore genuine UTF8.
+   */
+  /*  for (int i = 0; i < fl_selection_length[1]; i++) {
+        printf("%c[%x] ",fl_selection_buffer[1][i], fl_selection_buffer[1][i]);
+      } puts("");*/
+  int l_input = fl_selection_length[1], l = 0, i = 0, b;
+  char *str = new char[l_input];
+  while (i < l_input) {
+    if (i + 4 < l_input && fl_selection_buffer[1][i] == '\\' &&
+        fl_selection_buffer[1][i+3] == '\\' &&
+        isxdigit(fl_selection_buffer[1][i+1]) && isxdigit(fl_selection_buffer[1][i+1])) {
+      sscanf(fl_selection_buffer[1] + i + 1, "%x", &b);
+      int l_utf8 = fl_utf8len(b);
+      if (i + 3 * l_utf8 <= l_input && fl_selection_buffer[1][i+3*(l_utf8-1)] == '\\') {
+        while (l_utf8-- > 0) {
+          sscanf(fl_selection_buffer[1] + i + 1, "%x", &b);
+          str[l++] = b;
+          i += 3;
+        }
+        continue;
+      }
+    }
+    str[l++] = fl_selection_buffer[1][i++];
+  }
+  memcpy(fl_selection_buffer[1], str, l);
+  delete[] str;
+  fl_selection_length[1] = l;
+  fl_selection_buffer[1][l] = 0;
 }