Fix non-ASCII input in non-GUI frames on MS-Windows. (Bug#12055)

 src/w32inevt.c: Include w32inevt.h.
 (w32_read_console_input): New inline function, calls either
 ReadConsoleInputA or ReadConsoleInputW, depending on the value of
 w32_console_unicode_input.
 (fill_queue): Call w32_read_console_input instead of ReadConsoleInput.
 (w32_kbd_patch_key, key_event): Use the codepage returned by
 GetConsoleCP, rather than the ANSI codepage returned by GetLocaleInfo.
 (key_event): use uChar.UnicodeChar only if
 w32_console_unicode_input is non-zero.
 src/w32console.c: Include w32heap.h.
 <w32_console_unicode_input>: New global variable.
 (initialize_w32_display): Set w32_console_unicode_input to 1 on NT
 family of Windows, zero otherwise.
 src/w32inevt.h: Declare w32_console_unicode_input.
 lisp/international/mule-cmds.el (set-locale-environment): In a
 console session on MS-Windows, set up keyboard and terminal
 encoding from the OEM codepage, not the ANSI codepage.

4 files changed, 57 insertions, 16 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 8d0e7caf4ea..6457fc2209b 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,23 @@
 2012-07-28  Eli Zaretskii  <eliz@gnu.org>
 
+        Fix non-ASCII input in non-GUI frames on MS-Windows.  (Bug#12055)
+        * w32inevt.c: Include w32inevt.h.
+        (w32_read_console_input): New inline function, calls either
+        ReadConsoleInputA or ReadConsoleInputW, depending on the value of
+        w32_console_unicode_input.
+        (fill_queue): Call w32_read_console_input instead of ReadConsoleInput.
+        (w32_kbd_patch_key, key_event): Use the codepage returned by
+        GetConsoleCP, rather than the ANSI codepage returned by GetLocaleInfo.
+        (key_event): use uChar.UnicodeChar only if
+        w32_console_unicode_input is non-zero.
+
+        * w32console.c: Include w32heap.h.
+        <w32_console_unicode_input>: New global variable.
+        (initialize_w32_display): Set w32_console_unicode_input to 1 on NT
+        family of Windows, zero otherwise.
+
+        * w32inevt.h: Declare w32_console_unicode_input.
+
         * xdisp.c (init_iterator): Don't reference tip_frame in a build
         --without-x.  (Bug#11742)
 
diff --git a/src/w32console.c b/src/w32console.c
index 42d89cca6d7..c3a1c5d86b3 100644
--- a/src/w32console.c
+++ b/src/w32console.c
@@ -37,6 +37,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "termhooks.h"
 #include "termchar.h"
 #include "dispextern.h"
+#include "w32heap.h"    /* for os_subtype */
 #include "w32inevt.h"
 
 /* from window.c */
@@ -67,6 +68,7 @@ static CONSOLE_CURSOR_INFO prev_console_cursor;
 #endif
 
 HANDLE  keyboard_handle;
+int w32_console_unicode_input;
 
 
 /* Setting this as the ctrl handler prevents emacs from being killed when
@@ -786,6 +788,11 @@ initialize_w32_display (struct terminal *term)
                        info.srWindow.Left);
     }
 
+  if (os_subtype == OS_NT)
+    w32_console_unicode_input = 1;
+  else
+    w32_console_unicode_input = 0;
+
   /* Setup w32_display_info structure for this frame. */
 
   w32_initialize_display_info (build_string ("Console"));
diff --git a/src/w32inevt.c b/src/w32inevt.c
index a85fdbbe435..8d041194ca1 100644
--- a/src/w32inevt.c
+++ b/src/w32inevt.c
@@ -41,6 +41,7 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "termchar.h"
 #include "w32heap.h"
 #include "w32term.h"
+#include "w32inevt.h"
 
 /* stdin, from w32console.c */
 extern HANDLE keyboard_handle;
@@ -61,6 +62,15 @@ static INPUT_RECORD *queue_ptr = event_queue, *queue_end = event_queue;
 /* Temporarily store lead byte of DBCS input sequences.  */
 static char dbcs_lead = 0;
 
+static inline BOOL
+w32_read_console_input (HANDLE h, INPUT_RECORD *rec, DWORD recsize,
+                        DWORD *waiting)
+{
+  return (w32_console_unicode_input
+          ? ReadConsoleInputW (h, rec, recsize, waiting)
+          : ReadConsoleInputA (h, rec, recsize, waiting));
+}
+
 static int
 fill_queue (BOOL block)
 {
@@ -80,8 +90,8 @@ fill_queue (BOOL block)
         return 0;
     }
 
-  rc = ReadConsoleInput (keyboard_handle, event_queue, EVENT_QUEUE_SIZE,
-                         &events_waiting);
+  rc = w32_read_console_input (keyboard_handle, event_queue, EVENT_QUEUE_SIZE,
+                               &events_waiting);
   if (!rc)
     return -1;
   queue_ptr = event_queue;
@@ -224,7 +234,7 @@ w32_kbd_patch_key (KEY_EVENT_RECORD *event)
 #endif
 
   /* On NT, call ToUnicode instead and then convert to the current
-     locale's default codepage.  */
+     console input codepage.  */
   if (os_subtype == OS_NT)
     {
       WCHAR buf[128];
@@ -233,14 +243,9 @@ w32_kbd_patch_key (KEY_EVENT_RECORD *event)
                           keystate, buf, 128, 0);
       if (isdead > 0)
         {
-          char cp[20];
-          int cpId;
+          int cpId = GetConsoleCP ();
 
           event->uChar.UnicodeChar = buf[isdead - 1];
-
-          GetLocaleInfo (GetThreadLocale (),
-                         LOCALE_IDEFAULTANSICODEPAGE, cp, 20);
-          cpId = atoi (cp);
           isdead = WideCharToMultiByte (cpId, 0, buf, isdead,
                                         ansi_code, 4, NULL, NULL);
         }
@@ -447,26 +452,34 @@ key_event (KEY_EVENT_RECORD *event, struct input_event *emacs_ev, int *isdead)
         }
       else if (event->uChar.AsciiChar > 0)
         {
+          /* Pure ASCII characters < 128.  */
           emacs_ev->kind = ASCII_KEYSTROKE_EVENT;
           emacs_ev->code = event->uChar.AsciiChar;
         }
-      else if (event->uChar.UnicodeChar > 0)
+      else if (event->uChar.UnicodeChar > 0
+               && w32_console_unicode_input)
         {
+          /* Unicode codepoint; only valid if we are using Unicode
+             console input mode.  */
           emacs_ev->kind = MULTIBYTE_CHAR_KEYSTROKE_EVENT;
           emacs_ev->code = event->uChar.UnicodeChar;
         }
       else
         {
-          /* Fallback for non-Unicode versions of Windows.  */
+          /* Fallback handling of non-ASCII characters for non-Unicode
+             versions of Windows, and for non-Unicode input on NT
+             family of Windows.  Only characters in the current
+             console codepage are supported by this fallback.  */
           wchar_t code;
           char dbcs[2];
-          char cp[20];
           int cpId;
 
-          /* Get the codepage to interpret this key with.  */
-          GetLocaleInfo (GetThreadLocale (),
-                         LOCALE_IDEFAULTANSICODEPAGE, cp, 20);
-          cpId = atoi (cp);
+          /* Get the current console input codepage to interpret this
+             key with.  Note that the system defaults for the OEM
+             codepage could have been changed by calling SetConsoleCP
+             or w32-set-console-codepage, so using GetLocaleInfo to
+             get LOCALE_IDEFAULTCODEPAGE is not TRT here.  */
+          cpId = GetConsoleCP ();
 
           dbcs[0] = dbcs_lead;
           dbcs[1] = event->uChar.AsciiChar;
@@ -501,6 +514,7 @@ key_event (KEY_EVENT_RECORD *event, struct input_event *emacs_ev, int *isdead)
     }
   else
     {
+      /* Function keys and other non-character keys.  */
       emacs_ev->kind = NON_ASCII_KEYSTROKE_EVENT;
       emacs_ev->code = event->wVirtualKeyCode;
     }
diff --git a/src/w32inevt.h b/src/w32inevt.h
index d228637abfb..5386f2aa96c 100644
--- a/src/w32inevt.h
+++ b/src/w32inevt.h
@@ -19,6 +19,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #ifndef EMACS_W32INEVT_H
 #define EMACS_W32INEVT_H
 
+extern int w32_console_unicode_input;
+
 extern int w32_console_read_socket (struct terminal *term, int numchars,
                                     struct input_event *hold_quit);
 extern void w32_console_mouse_position (FRAME_PTR *f, int insist,