* w32fns.c (w32_wnd_proc) [WM_IME_STARTCOMPOSITION]: Position

IME window at cursor (Bug#2570).
(w32_wnd_proc) [WM_IME_CHAR]: Release context when finished.
(globals_of_w32fns): Dynamically load functions required above.

* w32term.c (w32_draw_window_cursor): Send message to reposition
any IME window.

1 files changed, 45 insertions, 0 deletions

diff --git a/src/w32fns.c b/src/w32fns.c
index 8ecf3ccb206..8b6c6c21cd2 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -252,6 +252,9 @@ typedef BOOL (WINAPI * TrackMouseEvent_Proc)
 typedef LONG (WINAPI * ImmGetCompositionString_Proc)
   (IN HIMC context, IN DWORD index, OUT LPVOID buffer, IN DWORD bufLen);
 typedef HIMC (WINAPI * ImmGetContext_Proc) (IN HWND window);
+typedef HWND (WINAPI * ImmReleaseContext_Proc) (IN HWND wnd, IN HIMC context);
+typedef HWND (WINAPI * ImmSetCompositionWindow_Proc) (IN HIMC context,
+                                                      IN COMPOSITIONFORM *form);
 typedef HMONITOR (WINAPI * MonitorFromPoint_Proc) (IN POINT pt, IN DWORD flags);
 typedef BOOL (WINAPI * GetMonitorInfo_Proc)
   (IN HMONITOR monitor, OUT struct MONITOR_INFO* info);
@@ -260,6 +263,8 @@ TrackMouseEvent_Proc track_mouse_event_fn = NULL;
 ClipboardSequence_Proc clipboard_sequence_fn = NULL;
 ImmGetCompositionString_Proc get_composition_string_fn = NULL;
 ImmGetContext_Proc get_ime_context_fn = NULL;
+ImmReleaseContext_Proc release_ime_context_fn = NULL;
+ImmSetCompositionWindow_Proc set_ime_composition_window_fn = NULL;
 MonitorFromPoint_Proc monitor_from_point_fn = NULL;
 GetMonitorInfo_Proc get_monitor_info_fn = NULL;
 
@@ -3158,6 +3163,8 @@ w32_wnd_proc (hwnd, msg, wParam, lParam)
           buffer = alloca(size);
           size = get_composition_string_fn (context, GCS_RESULTSTR,
                                             buffer, size);
+          release_ime_context_fn (hwnd, context);
+
           signal_user_input ();
           for (i = 0; i < size / sizeof (wchar_t); i++)
             {
@@ -3173,6 +3180,40 @@ w32_wnd_proc (hwnd, msg, wParam, lParam)
 
       break;
 
+    case WM_IME_STARTCOMPOSITION:
+      if (!set_ime_composition_window_fn)
+        goto dflt;
+      else
+        {
+          COMPOSITIONFORM form;
+          HIMC context;
+          struct window *w;
+
+          if (!context)
+            break;
+
+          f = x_window_to_frame (dpyinfo, hwnd);
+          w = XWINDOW (FRAME_SELECTED_WINDOW (f));
+
+          form.dwStyle = CFS_RECT;
+          form.ptCurrentPos.x = w32_system_caret_x;
+          form.ptCurrentPos.y = w32_system_caret_y;
+
+          form.rcArea.left = WINDOW_TEXT_TO_FRAME_PIXEL_X (w, 0);
+          form.rcArea.top = (WINDOW_TOP_EDGE_Y (w)
+                             + WINDOW_HEADER_LINE_HEIGHT (w));
+          form.rcArea.right = (WINDOW_BOX_RIGHT_EDGE_X (w)
+                               - WINDOW_RIGHT_MARGIN_WIDTH (w)
+                               - WINDOW_RIGHT_FRINGE_WIDTH (w));
+          form.rcArea.bottom = (WINDOW_BOTTOM_EDGE_Y (w)
+                                - WINDOW_MODE_LINE_HEIGHT (w));
+
+          context = get_ime_context_fn (hwnd);
+          set_ime_composition_window_fn (context, &form);
+          release_ime_context_fn (hwnd, context);
+        }
+      break;
+
     case WM_IME_ENDCOMPOSITION:
       ignore_ime_char = 0;
       goto dflt;
@@ -7278,6 +7319,10 @@ globals_of_w32fns ()
       GetProcAddress (imm32_lib, "ImmGetCompositionStringW");
     get_ime_context_fn = (ImmGetContext_Proc)
       GetProcAddress (imm32_lib, "ImmGetContext");
+    release_ime_context_fn = (ImmReleaseContext_Proc)
+      GetProcAddress (imm32_lib, "ImmReleaseContext");
+    set_ime_composition_window_fn = (ImmSetCompositionWindow_Proc)
+      GetProcAddress (imm32_lib, "ImmSetCompositionWindow");
   }
   DEFVAR_INT ("w32-ansi-code-page",
               &w32_ansi_code_page,