From a2c10f6189e078977db95e8493d79133d9b7c1e3 Mon Sep 17 00:00:00 2001
From: Solomon Peachy <pizza@shaftnet.org>
Date: Tue, 17 Dec 2024 08:55:21 -0500
Subject: [PATCH] unicode:  Support characters beyond the first unicode plane

We used 16-bit variables to store the 'character code' everywhere but
this won't let us represent anything beyond U+FFFF.

This patch changes those variables to a custom type that can be 32 or 16
bits depending on the build, and adjusts numerous internal APIs and
datastructures to match.  This includes:

 * utf8decode() and friends
 * font manipulation, caching, rendering, and generation
 * on-screen keyboard
 * FAT filesystem (parsing and generating utf16 LFNs)
 * WIN32 simulator platform code

Note that this patch doesn't _enable_ >16bit unicode support; a followup
patch will turn that on for appropriate targets.

Appears to work on:

  * hosted linux, native, linux simulator in both 16/32-bit modes.

Needs testing on:

  * windows and macos simulator (16bit+32bit)

Change-Id: Iba111b27d2433019b6bff937cf1ebd2c4353a0e8
---
 apps/hosted/android/keyboard.c               |   4 +-
 apps/keyboard.h                              |   2 +-
 apps/plugin.h                                |  14 +-
 apps/plugins/announce_status.c               |   6 +-
 apps/plugins/frotz/frotz.c                   |  10 +-
 apps/plugins/keyremap.c                      |   8 +-
 apps/plugins/lib/grey_draw.c                 |  24 ++--
 apps/plugins/lib/kbd_helper.c                |  12 +-
 apps/plugins/lib/kbd_helper.h                |  14 +-
 apps/plugins/lib/simple_viewer.c             |   2 +-
 apps/plugins/lrcplayer.c                     |   2 +-
 apps/plugins/lua/rocklib.c                   |   3 +-
 apps/plugins/mpegplayer/mpegplayer.c         |   4 +-
 apps/plugins/rockpaint.c                     |   4 +-
 apps/plugins/tagcache/tagcache.c             |   4 +-
 apps/plugins/text_viewer/tv_text_processor.c |  50 +++----
 apps/plugins/zxbox/zxbox_keyb.c              |   4 +-
 apps/recorder/keyboard.c                     |  66 ++++-----
 bootloader/iriver_h1x0.c                     |  10 +-
 bootloader/iriver_h300.c                     |  10 +-
 docs/PLUGIN_API                              |  10 +-
 firmware/arabjoin.h                          |   2 +
 firmware/bidi.c                              |  43 +++---
 firmware/common/diacritic.c                  |  26 ++--
 firmware/common/unicode.c                    |  35 ++++-
 firmware/drivers/fat.c                       |  49 +++++--
 firmware/drivers/lcd-bitmap-common.c         |  10 +-
 firmware/export/bidi.h                       |   2 +-
 firmware/export/config.h                     |   7 +
 firmware/export/cpu.h                        |   5 +
 firmware/export/font.h                       |  20 +--
 firmware/export/hangul.h                     |   3 +-
 firmware/font.c                              | 121 ++++++++++------
 firmware/font_cache.c                        |  33 +++--
 firmware/hangul.c                            |   6 +-
 firmware/include/diacritic.h                 |   2 +-
 firmware/include/font_cache.h                |  13 +-
 firmware/include/lru.h                       |   2 +-
 firmware/include/rbunicode.h                 |   5 +-
 firmware/target/hosted/filesystem-win32.c    | 143 ++++++++++++-------
 firmware/target/hosted/filesystem-win32.h    |   6 +-
 lib/rbcodec/metadata/id3tags.c               |   4 +-
 tools/convbdf.c                              |   4 +-
 tools/convttf.c                              |   2 +-
 44 files changed, 476 insertions(+), 330 deletions(-)

diff --git a/apps/hosted/android/keyboard.c b/apps/hosted/android/keyboard.c
index b74f67e782..f00a11ea6e 100644
--- a/apps/hosted/android/keyboard.c
+++ b/apps/hosted/android/keyboard.c
@@ -82,7 +82,7 @@ static void kdb_init(void)
         sleep(HZ/10);
 }
 
-int kbd_input(char* text, int buflen, unsigned short *kbd)
+int kbd_input(char* text, int buflen, ucschar_t *kbd)
 {
 	(void)kbd;
     JNIEnv e            = *env_ptr;
@@ -107,7 +107,7 @@ int kbd_input(char* text, int buflen, unsigned short *kbd)
     e->DeleteLocalRef(env_ptr, str);
     e->DeleteLocalRef(env_ptr, ok_text);
     e->DeleteLocalRef(env_ptr, cancel_text);
-    
+
     return !accepted; /* return 0 on success */
 }
 
diff --git a/apps/keyboard.h b/apps/keyboard.h
index e3ee0b05d0..a2d497c28e 100644
--- a/apps/keyboard.h
+++ b/apps/keyboard.h
@@ -23,7 +23,7 @@
 
 /* '*kbd', same format as https://www.rockbox.org/wiki/LoadableKeyboardLayouts */
 
-int kbd_input(char* buffer, int buflen, unsigned short *kbd);
+int kbd_input(char* buffer, int buflen, ucschar_t *kbd);
 
 int load_kbd(unsigned char* filename);
 
diff --git a/apps/plugin.h b/apps/plugin.h
index 5be1147cab..a0c41a20e7 100644
--- a/apps/plugin.h
+++ b/apps/plugin.h
@@ -176,7 +176,7 @@ int plugin_open(const char *plugin, const char *parameter);
  * when this happens please take the opportunity to sort in
  * any new functions "waiting" at the end of the list.
  */
-#define PLUGIN_API_VERSION 273
+#define PLUGIN_API_VERSION 274
 
 /* 239 Marks the removal of ARCHOS HWCODEC and CHARCELL */
 
@@ -296,15 +296,15 @@ struct plugin_api {
 #if defined(HAVE_LCD_ENABLE) || defined(HAVE_LCD_SLEEP)
     void (*button_queue_post)(long id, intptr_t data);
 #endif
-    unsigned short *(*bidi_l2v)( const unsigned char *str, int orientation );
-    bool (*is_diacritic)(const unsigned short char_code, bool *is_rtl);
-    const unsigned char *(*font_get_bits)( struct font *pf, unsigned short char_code );
+    ucschar_t *(*bidi_l2v)(const unsigned char *str, int orientation);
+    bool (*is_diacritic)(const ucschar_t char_code, bool *is_rtl);
+    const unsigned char *(*font_get_bits)(struct font *pf, ucschar_t char_code);
     int (*font_load)(const char *path);
     void (*font_unload)(int font_id);
     struct font* (*font_get)(int font);
     int  (*font_getstringsize)(const unsigned char *str, int *w, int *h,
                                int fontnumber);
-    int (*font_get_width)(struct font* pf, unsigned short char_code);
+    int (*font_get_width)(struct font* pf, ucschar_t char_code);
     void (*screen_clear_area)(struct screen * display, int xstart, int ystart,
                               int width, int height);
     void (*gui_scrollbar_draw)(struct screen * screen, int x, int y,
@@ -667,7 +667,7 @@ struct plugin_api {
                               const unsigned char * const *units,
                               unsigned int unit_count, bool binary_scale);
     /* unicode stuff */
-    const unsigned char* (*utf8decode)(const unsigned char *utf8, unsigned short *ucs);
+    const unsigned char* (*utf8decode)(const unsigned char *utf8, ucschar_t *ucs);
     unsigned char* (*iso_decode)(const unsigned char *iso, unsigned char *utf8, int cp, int count);
     unsigned char* (*utf16LEdecode)(const unsigned char *utf16, unsigned char *utf8, int count);
     unsigned char* (*utf16BEdecode)(const unsigned char *utf16, unsigned char *utf8, int count);
@@ -923,7 +923,7 @@ struct plugin_api {
     int  (*rand)(void);
     void (*qsort)(void *base, size_t nmemb, size_t size,
                   int(*compar)(const void *, const void *));
-    int (*kbd_input)(char* buffer, int buflen, unsigned short *kbd);
+    int (*kbd_input)(char* buffer, int buflen, ucschar_t *kbd);
     struct tm* (*get_time)(void);
     struct tm * (*gmtime_r)(const time_t *timep, struct tm *tm);
 #if CONFIG_RTC
diff --git a/apps/plugins/announce_status.c b/apps/plugins/announce_status.c
index 21518b4d68..214a3812c2 100644
--- a/apps/plugins/announce_status.c
+++ b/apps/plugins/announce_status.c
@@ -70,7 +70,7 @@ static const char keybd_layout[] =
  * - \n does not create a key, but it also consumes one element
  * - the final null terminator is equivalent to \n
  * - since sizeof includes the null terminator we don't need +1 for that. */
-static unsigned short kbd_buf[sizeof(keybd_layout)];
+static ucschar_t kbd_buf[sizeof(keybd_layout)];
 
 /****************** prototypes ******************/
 void print_scroll(char* string); /* implements a scrolling screen */
@@ -164,7 +164,7 @@ static void config_set_defaults(void)
     gAnnounce.announce_on = 0;
     gAnnounce.grouping = 0;
     gAnnounce.wps_fmt[0] = '\0';
-    gAnnounce.show_prompt = true; 
+    gAnnounce.show_prompt = true;
 }
 
 static void config_reset_voice(void)
@@ -250,7 +250,7 @@ static int announce_menu_cb(int action,
                             struct gui_synclist *this_list)
 {
     (void)this_item;
-    unsigned short* kbd_p;
+    ucschar_t *kbd_p;
 
     int selection = rb->gui_synclist_get_sel_pos(this_list);
 
diff --git a/apps/plugins/frotz/frotz.c b/apps/plugins/frotz/frotz.c
index 4c12cfcd10..31fb668e60 100644
--- a/apps/plugins/frotz/frotz.c
+++ b/apps/plugins/frotz/frotz.c
@@ -128,7 +128,7 @@ void wait_for_key()
         case PLA_EXIT:
             hot_key_quit();
             break;
-        
+
         case PLA_SELECT:
             return;
         }
@@ -159,7 +159,7 @@ zchar do_input(int timeout, bool show_cursor)
         {
         case PLA_EXIT:
             return ZC_HKEY_QUIT;
-        
+
         case PLA_CANCEL:
             menu_ret = menu();
             if (menu_ret != ZC_BAD)
@@ -174,7 +174,7 @@ zchar do_input(int timeout, bool show_cursor)
             return ZC_BAD;
 
         default:
-            if (timeout != TIMEOUT_BLOCK && 
+            if (timeout != TIMEOUT_BLOCK &&
                     !TIME_BEFORE(*rb->current_tick, timeout_at))
                 return ZC_TIME_OUT;
         }
@@ -185,7 +185,7 @@ zchar os_read_key(int timeout, bool show_cursor)
 {
     int r;
     char inputbuf[5];
-    short key;
+    ucschar_t key;
     zchar zkey;
 
     for(;;)
@@ -214,7 +214,7 @@ zchar os_read_line(int max, zchar *buf, int timeout, int width, int continued)
     char inputbuf[256];
     const char *in;
     char *out;
-    short key;
+    ucschar_t key;
     zchar zkey;
 
     for(;;)
diff --git a/apps/plugins/keyremap.c b/apps/plugins/keyremap.c
index 202d5fcfa4..bb7e965963 100644
--- a/apps/plugins/keyremap.c
+++ b/apps/plugins/keyremap.c
@@ -206,8 +206,8 @@ static int prompt_filename(char *buf, size_t bufsz)
 {
 #define KBD_LAYOUT "abcdefghijklmnop\nqrstuvwxyz |()[]\n1234567890 /._-+\n\n" \
                    "\nABCDEFGHIJKLMNOP\nQRSTUVWXYZ |()[]\n1234567890 /._-+"
-    unsigned short kbd[sizeof(KBD_LAYOUT) + 10];
-    unsigned short *kbd_p = kbd;
+    ucschar_t kbd[sizeof(KBD_LAYOUT) + 10];
+    ucschar_t *kbd_p = kbd;
     if (!kbd_create_layout(KBD_LAYOUT, kbd, sizeof(kbd)))
         kbd_p = NULL;
 
@@ -1002,7 +1002,7 @@ next_line:
                 {
                     bufleft = bufsz - (pctx - filenamebuf);
                     ctx = -1;
-                    int ctx_x_flag_count = (LAST_CONTEXT_PLACEHOLDER 
+                    int ctx_x_flag_count = (LAST_CONTEXT_PLACEHOLDER
                                            * ARRAYLEN(context_flags));
 
                     for (int i=0;i < ctx_x_flag_count ;i++)
@@ -2058,7 +2058,7 @@ static void synclist_set(int id, int selected_item, int items, int sel_size)
     }
     else if (menu_id == MENU_ID(M_SETKEYS))
     {
-        keyset.view_columns = printcell_set_columns(&lists, NULL, 
+        keyset.view_columns = printcell_set_columns(&lists, NULL,
                                                   ACTVIEW_HEADER, Icon_Rockbox);
         printcell_enable(true);
         int curcol = printcell_get_column_selected();
diff --git a/apps/plugins/lib/grey_draw.c b/apps/plugins/lib/grey_draw.c
index 298ffbe16e..481b34d3ad 100644
--- a/apps/plugins/lib/grey_draw.c
+++ b/apps/plugins/lib/grey_draw.c
@@ -199,8 +199,8 @@ void grey_hline(int x1, int x2, int y)
     /* nothing to draw? */
     if (y < _grey_info.clip_t || y >= _grey_info.clip_b ||
         x1 >= _grey_info.clip_r || x2 < _grey_info.clip_l)
-        return;  
-    
+        return;
+
     /* drawmode and optimisation */
     if (vp->drawmode & DRMODE_INVERSEVID)
     {
@@ -251,7 +251,7 @@ void grey_vline(int x, int y1, int y2)
     unsigned char *dst, *dst_end;
     void (*pfunc)(unsigned char *address);
     int dwidth;
-    
+
     /* direction flip */
     if (y2 < y1)
     {
@@ -264,7 +264,7 @@ void grey_vline(int x, int y1, int y2)
     if (x < _grey_info.clip_l || x >= _grey_info.clip_r ||
         y1 >= _grey_info.clip_b || y2 < _grey_info.clip_t)
         return;
-    
+
     /* clipping */
     if (y1 < _grey_info.clip_t)
         y1 = _grey_info.clip_t;
@@ -425,7 +425,7 @@ void grey_fillrect(int x, int y, int width, int height)
 
     if (height <= 0)
         return;
-    
+
     dwidth  = _grey_info.cb_width;
     dst     = &_grey_info.curbuffer[
                 _GREY_MULUQ(dwidth, _grey_info.vp->y - _grey_info.cb_y + y) +
@@ -653,8 +653,8 @@ void grey_gray_bitmap(const unsigned char *src, int x, int y, int width,
 /* Put a string at a given pixel position, skipping first ofs pixel columns */
 void grey_putsxyofs(int x, int y, int ofs, const unsigned char *str)
 {
-    int ch;
-    unsigned short *ucs;
+    ucschar_t ch;
+    ucschar_t *ucs;
     struct font* pf;
 
     if (_grey_info.clip_b <= _grey_info.clip_t)
@@ -680,7 +680,7 @@ void grey_putsxyofs(int x, int y, int ofs, const unsigned char *str)
         bits = rb->font_get_bits(pf, ch);
 
         grey_mono_bitmap_part(bits, ofs, 0, width, x, y, width - ofs, pf->height);
-        
+
         x += width - ofs;
         ofs = 0;
     }
@@ -709,7 +709,7 @@ void grey_ub_clear_display(void)
 #endif
 }
 
-/* Assembler optimised helper function for copying a single line to the 
+/* Assembler optimised helper function for copying a single line to the
  * greyvalue buffer. */
 void _grey_line1(int width, unsigned char *dst, const unsigned char *src,
                  const unsigned char *lut);
@@ -725,7 +725,7 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
     if ((width <= 0) || (height <= 0) || (x >= _grey_info.width)
         || (y >= _grey_info.height) || (x + width <= 0) || (y + height <= 0))
         return;
-        
+
     /* clipping */
     if (x < 0)
     {
@@ -744,7 +744,7 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
     if (y + height > _grey_info.height)
         height = _grey_info.height - y;
 
-    src += _GREY_MULUQ(stride, src_y) + src_x; /* move starting point */ 
+    src += _GREY_MULUQ(stride, src_y) + src_x; /* move starting point */
     yc = y;
     ye = y + height;
     dst = _grey_info.values + (x << _GREY_BSHIFT);
@@ -773,7 +773,7 @@ void grey_ub_gray_bitmap_part(const unsigned char *src, int src_x, int src_y,
         }
         while (src_row < src_end);
 #endif
-        
+
         src += stride;
     }
     while (++yc < ye);
diff --git a/apps/plugins/lib/kbd_helper.c b/apps/plugins/lib/kbd_helper.c
index f99282575d..0f7bbff8f7 100644
--- a/apps/plugins/lib/kbd_helper.c
+++ b/apps/plugins/lib/kbd_helper.c
@@ -22,8 +22,8 @@
 #include "kbd_helper.h"
 
 /*  USAGE:
-    unsigned short kbd[64];
-    unsigned short *kbd_p = kbd;
+    ucschar_t kbd[64];
+    ucschar_t *kbd_p = kbd;
     if (!kbd_create_layout("ABCD1234\n", kbd, sizeof(kbd)))
         kbd_p = NULL;
 
@@ -34,14 +34,14 @@
  * success returns size of buffer used
  * failure returns 0
 */
-int kbd_create_layout(const char *layout, unsigned short *buf, int bufsz)
+int kbd_create_layout(const char *layout, ucschar_t *buf, int bufsz)
 {
-    unsigned short *pbuf;
+    ucschar_t *pbuf;
     const unsigned char *p = layout;
     int len = 0;
     int total_len = 0;
     pbuf = buf;
-    while (*p && (pbuf - buf + (ptrdiff_t) sizeof(unsigned short)) < bufsz)
+    while (*p && (pbuf - buf + (ptrdiff_t) sizeof(ucschar_t)) < bufsz)
     {
         p = rb->utf8decode(p, &pbuf[len+1]);
         if (pbuf[len+1] == '\n')
@@ -60,7 +60,7 @@ int kbd_create_layout(const char *layout, unsigned short *buf, int bufsz)
         *pbuf = len;
         pbuf[len+1] = 0xFEFF;   /* mark end of characters */
         total_len += len + 1;
-        return total_len * sizeof(unsigned short);
+        return total_len * sizeof(ucschar_t);
     }
 
     return 0;
diff --git a/apps/plugins/lib/kbd_helper.h b/apps/plugins/lib/kbd_helper.h
index ee2ce7551c..ef24700309 100644
--- a/apps/plugins/lib/kbd_helper.h
+++ b/apps/plugins/lib/kbd_helper.h
@@ -1,10 +1,10 @@
 /***************************************************************************
- *             __________               __   ___.                  
- *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___  
- *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /  
- *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <   
- *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \  
- *                     \/            \/     \/    \/            \/ 
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
  * $Id$
  *
  * Copyright (C) 2020 William Wilgus
@@ -22,6 +22,6 @@
 #define KBD_HELPER_H
 
 /* create a custom keyboard layout for kbd_input */
-int kbd_create_layout(const char *layout, unsigned short *buf, int bufsz);
+int kbd_create_layout(const char *layout, ucschar_t *buf, int bufsz);
 
 #endif /* KBD_HELPER_H */
diff --git a/apps/plugins/lib/simple_viewer.c b/apps/plugins/lib/simple_viewer.c
index 07176eb991..e71efce753 100644
--- a/apps/plugins/lib/simple_viewer.c
+++ b/apps/plugins/lib/simple_viewer.c
@@ -62,7 +62,7 @@ static const char* get_next_line(const char *text, struct view_info *info)
     total = 0;
     while(*ptr)
     {
-        unsigned short ch;
+        ucschar_t ch;
         n = ((intptr_t)rb->utf8decode(ptr, &ch) - (intptr_t)ptr);
         if (rb->is_diacritic(ch, NULL))
             w = 0;
diff --git a/apps/plugins/lrcplayer.c b/apps/plugins/lrcplayer.c
index d341e6b7a5..659373259d 100644
--- a/apps/plugins/lrcplayer.c
+++ b/apps/plugins/lrcplayer.c
@@ -422,7 +422,7 @@ static struct lrc_brpos *calc_brpos(struct lrc_line *lrc_line, int i)
     int nlrcbrpos = 0, max_lrcbrpos;
     uifont = rb->screens[0]->getuifont();
     struct font* pf = rb->font_get(uifont);
-    unsigned short ch;
+    ucschar_t ch;
     struct snap {
         int count, width;
         int nword;
diff --git a/apps/plugins/lua/rocklib.c b/apps/plugins/lua/rocklib.c
index 9931d65326..3a318fcd96 100644
--- a/apps/plugins/lua/rocklib.c
+++ b/apps/plugins/lua/rocklib.c
@@ -141,6 +141,7 @@ RB_WRAP(touchscreen_mode)
 
 #endif
 
+// XXX this may be broken with 32-bit ucschar_t
 RB_WRAP(kbd_input)
 {
     /*kbd_input(text, layout)*
@@ -168,7 +169,7 @@ RB_WRAP(kbd_input)
         layout = NULL;
     }
 
-    if(!rb->kbd_input(buffer, LUAL_BUFFERSIZE, (unsigned short *)layout))
+    if(!rb->kbd_input(buffer, LUAL_BUFFERSIZE, (ucschar_t *)layout))
     {
         luaL_addstring(&b, buffer);
         luaL_pushresult(&b);
diff --git a/apps/plugins/mpegplayer/mpegplayer.c b/apps/plugins/mpegplayer/mpegplayer.c
index 96645d48ea..1ece91d908 100644
--- a/apps/plugins/mpegplayer/mpegplayer.c
+++ b/apps/plugins/mpegplayer/mpegplayer.c
@@ -1073,8 +1073,8 @@ static void draw_oriented_alpha_bitmap_part(const unsigned char *src,
 
 static void draw_putsxy_oriented(int x, int y, const char *str)
 {
-    unsigned short ch;
-    unsigned short *ucs;
+    ucschar_t ch;
+    ucschar_t *ucs;
     int ofs = MIN(x, 0);
     struct font* pf = rb->font_get(osd.font);
 
diff --git a/apps/plugins/rockpaint.c b/apps/plugins/rockpaint.c
index 05174ad034..a0fe37b6f4 100644
--- a/apps/plugins/rockpaint.c
+++ b/apps/plugins/rockpaint.c
@@ -969,8 +969,8 @@ static void buffer_alpha_bitmap_part(
 static void buffer_putsxyofs( fb_data *buf, int buf_width, int buf_height,
                               int x, int y, int ofs, const unsigned char *str )
 {
-    unsigned short ch;
-    unsigned short *ucs;
+    ucschar_t ch;
+    ucschar_t *ucs;
 
     struct font *pf = rb->font_get( FONT_UI );
     if( !pf ) pf = rb->font_get( FONT_SYSFIXED );
diff --git a/apps/plugins/tagcache/tagcache.c b/apps/plugins/tagcache/tagcache.c
index 87d2aa4c10..483d2fbaf9 100644
--- a/apps/plugins/tagcache/tagcache.c
+++ b/apps/plugins/tagcache/tagcache.c
@@ -135,10 +135,10 @@ static void sleep_yield(void)
     #define yield sleep_yield
 }
 
-/* make sure tag can be displayed by font pf*/
+/* make sure tag can be displayed by font pf */
 static bool text_is_displayable(struct font *pf, unsigned char *src)
 {
-    unsigned short code;
+    ucschar_t code;
     const unsigned char *ptr = src;
     while(*ptr)
     {
diff --git a/apps/plugins/text_viewer/tv_text_processor.c b/apps/plugins/text_viewer/tv_text_processor.c
index db96d61409..8bc8519780 100644
--- a/apps/plugins/text_viewer/tv_text_processor.c
+++ b/apps/plugins/text_viewer/tv_text_processor.c
@@ -41,7 +41,7 @@ static unsigned text_type = TV_TEXT_UNKNOWN;
 
 static const unsigned char *end_ptr;
 
-static unsigned short ucsbuf[TV_MAX_BLOCKS][TV_MAX_CHARS_PER_BLOCK];
+static ucschar_t ucsbuf[TV_MAX_BLOCKS][TV_MAX_CHARS_PER_BLOCK];
 static unsigned char  utf8buf[TV_MAX_CHARS_PER_BLOCK * (2 * 3)];
 static unsigned char  *outbuf;
 
@@ -54,11 +54,11 @@ static bool expand_extra_line = false;
 /* when a line is divided, this value sets true. */
 static bool is_break_line = false;
 
-static unsigned short break_chars[] =
+static unsigned short break_chars[] = // XXX promote to ucschar_t if we get a codepoint > 0xffff
     {
         0,
         /* halfwidth characters */
-        '\t', '\n', 0x0b, 0x0c, ' ', '!', ',', '-', '.', ':', ';', '?', 0xb7, 
+        '\t', '\n', 0x0b, 0x0c, ' ', '!', ',', '-', '.', ':', ';', '?', 0xb7,
         /* fullwidth characters */
         0x2010, /* hyphen */
         0x3000, /* fullwidth space */
@@ -76,7 +76,7 @@ static unsigned short break_chars[] =
     };
 
 /* the characters which is not judged as space with isspace() */
-static unsigned short extra_spaces[] = { 0, 0x3000 };
+static unsigned short extra_spaces[] = { 0, 0x3000 }; // XXX promote to ucschar_t if we get a codepoint > 0xffff
 
 static int tv_glyph_width(int ch)
 {
@@ -93,7 +93,7 @@ static int tv_glyph_width(int ch)
     return rb->font_get_width(rb->font_get(preferences->font_id), ch);
 }
 
-static unsigned char *tv_get_ucs(const unsigned char *str, unsigned short *ch)
+static unsigned char *tv_get_ucs(const unsigned char *str, ucschar_t *ch)
 {
     int count = 1;
     unsigned char utf8_tmp[3];
@@ -148,7 +148,7 @@ static unsigned char *tv_get_ucs(const unsigned char *str, unsigned short *ch)
     return (unsigned char *)str + count;
 }
 
-static void tv_decode2utf8(const unsigned short *ucs, int count)
+static void tv_decode2utf8(const ucschar_t *ucs, int count)
 {
     int i;
 
@@ -158,7 +158,7 @@ static void tv_decode2utf8(const unsigned short *ucs, int count)
     *outbuf = '\0';
 }
 
-static bool tv_is_line_break_char(unsigned short ch)
+static bool tv_is_line_break_char(ucschar_t ch)
 {
     size_t i;
 
@@ -166,7 +166,7 @@ static bool tv_is_line_break_char(unsigned short ch)
     if (preferences->word_mode == WM_CHOP)
         return false;
 
-    for (i = 0; i < sizeof(break_chars)/sizeof(unsigned short); i++)
+    for (i = 0; i < sizeof(break_chars)/sizeof(ucschar_t); i++)
     {
         if (break_chars[i] == ch)
             return true;
@@ -174,14 +174,14 @@ static bool tv_is_line_break_char(unsigned short ch)
     return false;
 }
 
-static bool tv_isspace(unsigned short ch)
+static bool tv_isspace(ucschar_t ch)
 {
     size_t i;
 
     if (ch < 128 && isspace(ch))
         return true;
 
-    for (i = 0; i < sizeof(extra_spaces)/sizeof(unsigned short); i++)
+    for (i = 0; i < sizeof(extra_spaces)/sizeof(ucschar_t); i++)
     {
         if (extra_spaces[i] == ch)
             return true;
@@ -191,17 +191,17 @@ static bool tv_isspace(unsigned short ch)
 
 static bool tv_is_break_line_join_mode(const unsigned char *next_str)
 {
-    unsigned short ch;
+    ucschar_t ch;
 
     tv_get_ucs(next_str, &ch);
     return tv_isspace(ch);
 }
 
-static int tv_form_reflow_line(unsigned short *ucs, int chars)
+static int tv_form_reflow_line(ucschar_t *ucs, int chars)
 {
-    unsigned short new_ucs[TV_MAX_CHARS_PER_BLOCK];
-    unsigned short *p = new_ucs;
-    unsigned short ch;
+    ucschar_t new_ucs[TV_MAX_CHARS_PER_BLOCK];
+    ucschar_t *p = new_ucs;
+    ucschar_t ch;
     int i;
     int k;
     int expand_spaces;
@@ -262,15 +262,15 @@ static int tv_form_reflow_line(unsigned short *ucs, int chars)
         }
     }
 
-    rb->memcpy(ucs, new_ucs, sizeof(unsigned short) * TV_MAX_CHARS_PER_BLOCK);
+    rb->memcpy(ucs, new_ucs, sizeof(ucschar_t) * TV_MAX_CHARS_PER_BLOCK);
     return indent_chars + nonspace_chars + expand_spaces;
 }
 
 static void tv_align_right(int *block_chars)
 {
-    unsigned short *cur_text;
-    unsigned short *prev_text;
-    unsigned short ch;
+    ucschar_t *cur_text;
+    ucschar_t *prev_text;
+    ucschar_t ch;
     int cur_block = block_count - 1;
     int prev_block;
     int cur_chars;
@@ -335,9 +335,9 @@ static void tv_align_right(int *block_chars)
             if (break_pos < prev_chars)
             {
                 rb->memmove(cur_text + prev_chars - break_pos,
-                            cur_text, block_chars[cur_block] * sizeof(unsigned short));
+                            cur_text, block_chars[cur_block] * sizeof(ucschar_t));
                 rb->memcpy(cur_text, prev_text + break_pos,
-                           (prev_chars - break_pos) * sizeof(unsigned short));
+                           (prev_chars - break_pos) * sizeof(ucschar_t));
 
                 block_chars[prev_block]  = break_pos;
                 block_chars[cur_block ] += prev_chars - break_pos;
@@ -347,15 +347,15 @@ static void tv_align_right(int *block_chars)
     }
 }
 
-static int tv_parse_text(const unsigned char *src, unsigned short *ucs,
+static int tv_parse_text(const unsigned char *src, ucschar_t *ucs,
                              int *ucs_chars, bool is_indent)
 {
     const unsigned char *cur  = src;
     const unsigned char *next = src;
     const unsigned char *line_break_ptr = NULL;
     const unsigned char *line_end_ptr   = NULL;
-    unsigned short ch = 0;
-    unsigned short prev_ch;
+    ucschar_t ch = 0;
+    ucschar_t prev_ch;
     int chars = 0;
     int gw;
     int line_break_width = 0;
@@ -480,7 +480,7 @@ static int tv_parse_text(const unsigned char *src, unsigned short *ucs,
 int tv_create_formed_text(const unsigned char *src, ssize_t bufsize,
                               int block, bool is_multi, const unsigned char **dst)
 {
-    unsigned short ch;
+    ucschar_t ch;
     int chars[block_count];
     int i;
     int size = 0;
diff --git a/apps/plugins/zxbox/zxbox_keyb.c b/apps/plugins/zxbox/zxbox_keyb.c
index 6ec04ec04b..56e0025c60 100644
--- a/apps/plugins/zxbox/zxbox_keyb.c
+++ b/apps/plugins/zxbox/zxbox_keyb.c
@@ -326,7 +326,7 @@
 struct keyboard_parameters {
     const unsigned char* default_kbd;
     int DEFAULT_LINES;
-    unsigned short kbd_buf[KBD_BUF_SIZE];
+    ucschar_t kbd_buf[KBD_BUF_SIZE];
     int nchars;
     int font_w;
     int font_h;
@@ -358,7 +358,7 @@ int zx_kbd_input(char* text/*, int buflen*/)
     int editpos, len_utf8;
 #endif
 /*    int statusbar_size = global_settings.statusbar ? STATUSBAR_HEIGHT : 0;*/
-    unsigned short ch/*, tmp, hlead = 0, hvowel = 0, htail = 0*/;
+    ucschar_t ch/*, tmp, hlead = 0, hvowel = 0, htail = 0*/;
     /*bool hangul = false;*/
     unsigned char *utf8;
     const unsigned char *p;
diff --git a/apps/recorder/keyboard.c b/apps/recorder/keyboard.c
index 0b85918dc1..0b8dbea06c 100644
--- a/apps/recorder/keyboard.c
+++ b/apps/recorder/keyboard.c
@@ -90,15 +90,15 @@ enum ekbd_viewports
 struct keyboard_parameters
 {
     struct viewport *kbd_viewports;
-    unsigned short kbd_buf[KBD_BUF_SIZE];
-    unsigned short *kbd_buf_ptr;
+    ucschar_t kbd_buf[KBD_BUF_SIZE];
+    ucschar_t *kbd_buf_ptr;
     unsigned short max_line_len;
     int default_lines;
-    int last_k;
-    int last_i;
-    int font_w;
-    int font_h;
-    int text_w;
+    unsigned int last_k;
+    unsigned int last_i;
+    unsigned short font_w;
+    unsigned short font_h;
+    unsigned int text_w;
     int curfont;
     int main_y;
 #ifdef HAVE_MORSE_INPUT
@@ -128,7 +128,7 @@ struct edit_state
     int editpos;        /* Edit position on all screens */
     bool cur_blink;     /* Cursor on/off flag */
     bool hangul;
-    unsigned short hlead, hvowel, htail;
+    ucschar_t hlead, hvowel, htail;
 #ifdef HAVE_MORSE_INPUT
     bool morse_mode;
     bool morse_reading;
@@ -158,13 +158,13 @@ static void keyboard_layout(struct viewport *kbd_vp,
 {
      /*Note: viewports are initialized to vp_default by kbd_create_viewports */
 
-    int sc_w = sc->getwidth();
-    int sc_h = sc->getheight();
+    unsigned short sc_w = sc->getwidth();
+    unsigned short sc_h = sc->getheight();
 
     /* TEXT */
     struct viewport *vp = &kbd_vp[eKBD_VP_TEXT];
     /* make sure height is even for the text box */
-    int text_height = (MAX(pm->font_h, get_icon_height(sc->screen_type)) & ~1) + 2;
+    unsigned short text_height = (MAX(pm->font_h, (unsigned int)get_icon_height(sc->screen_type)) & ~1) + 2;
     vp->x = 0; /* LEFT */
     vp->y = 0; /* TOP */
     vp->width = sc_w;
@@ -224,7 +224,7 @@ int load_kbd(unsigned char* filename)
     int fd;
     int i, line_len, max_line_len;
     unsigned char buf[4];
-    unsigned short *pbuf;
+    ucschar_t *pbuf;
 
     if (filename == NULL)
     {
@@ -245,7 +245,7 @@ int load_kbd(unsigned char* filename)
         /* check how many bytes to read for this character */
         static const unsigned char sizes[4] = { 0x80, 0xe0, 0xf0, 0xf5 };
         size_t count;
-        unsigned short ch;
+        ucschar_t ch;
 
         for (count = 0; count < ARRAYLEN(sizes); count++)
         {
@@ -297,7 +297,7 @@ int load_kbd(unsigned char* filename)
         struct keyboard_parameters *pm = &kbd_param[l];
 #if NB_SCREENS > 1
         if (l > 0)
-            memcpy(pm->kbd_buf, kbd_param[0].kbd_buf, i*sizeof(unsigned short));
+            memcpy(pm->kbd_buf, kbd_param[0].kbd_buf, i*sizeof(ucschar_t));
 #endif
         /* initialize parameters */
         pm->x = pm->y = pm->page = 0;
@@ -309,7 +309,7 @@ int load_kbd(unsigned char* filename)
 }
 
 /* helper function to spell a char */
-static void kbd_spellchar(unsigned short c)
+static void kbd_spellchar(ucschar_t c)
 {
     unsigned char tmp[5];
     /* store char to pass to talk_spell */
@@ -322,7 +322,7 @@ static void kbd_spellchar(unsigned short c)
         talk_spell(tmp, false);
 }
 
-static void kbd_inschar(struct edit_state *state, unsigned short ch)
+static void kbd_inschar(struct edit_state *state, ucschar_t ch)
 {
     int i, j, len;
     unsigned char tmp[4];
@@ -361,10 +361,10 @@ static void kbd_delchar(struct edit_state *state)
 }
 
 /* Lookup k value based on state of param (pm) */
-static unsigned short get_kbd_ch(struct keyboard_parameters *pm, int x, int y)
+static ucschar_t get_kbd_ch(struct keyboard_parameters *pm, int x, int y)
 {
-    int i = 0, k = pm->page*pm->lines + y, n;
-    unsigned short *pbuf;
+    unsigned int n, i = 0, k = pm->page*pm->lines + y;
+    ucschar_t *pbuf;
     if (k >= pm->last_k)
     {
         i = pm->last_i;
@@ -406,12 +406,12 @@ static void kbd_move_picker_horizontal(struct keyboard_parameters *pm,
 static void kbd_move_picker_vertical(struct keyboard_parameters *pm,
                                      struct edit_state *state, int dir);
 
-int kbd_input(char* text, int buflen, unsigned short *kbd)
+int kbd_input(char* text, int buflen, ucschar_t *kbd)
 {
     bool done = false;
     struct keyboard_parameters * const param = kbd_param;
     struct edit_state state;
-    unsigned short ch;
+    ucschar_t ch;
     int ret = 0; /* assume success */
     FOR_NB_SCREENS(l)
     {
@@ -449,7 +449,7 @@ int kbd_input(char* text, int buflen, unsigned short *kbd)
         FOR_NB_SCREENS(l)
         {
             struct keyboard_parameters *pm = &param[l];
-            unsigned short *pbuf;
+            ucschar_t *pbuf;
             const unsigned char *p;
             int len = 0;
 
@@ -800,8 +800,8 @@ static void kbd_calc_pm_params(struct keyboard_parameters *pm,
 {
     struct font* font;
     const unsigned char *p;
-    unsigned short ch, *pbuf;
-    int i, w;
+    ucschar_t ch, *pbuf;
+    unsigned int i, w;
 #ifdef HAVE_TOUCHSCREEN
     pm->show_buttons = (sc->screen_type == SCREEN_MAIN &&
                                 (touchscreen_get_mode() == TOUCHSCREEN_POINT));
@@ -812,7 +812,7 @@ static void kbd_calc_pm_params(struct keyboard_parameters *pm,
     pm->font_h = font->height;
 
     /* check if FONT_UI fits the screen */
-    if (2*pm->font_h + 3 > sc->getheight())
+    if (pm->font_h*2 + 3 > sc->getheight())
     {
         pm->curfont = FONT_SYSFIXED;
         font = font_get(FONT_SYSFIXED);
@@ -858,9 +858,9 @@ static void kbd_calc_vp_params(struct keyboard_parameters *pm,
 {
     (void) state;
     struct viewport *vp = &pm->kbd_viewports[eKBD_VP_PICKER];
-    int icon_w, sc_w, sc_h;
+    unsigned int icon_w, sc_w, sc_h;
     int i, total_lines;
-    unsigned short *pbuf;
+    ucschar_t *pbuf;
     /* calculate how many characters to put in a row. */
     icon_w = get_icon_width(sc->screen_type);
 
@@ -970,7 +970,7 @@ static void kbd_draw_picker(struct keyboard_parameters *pm,
         x = 0;
         y = 0;
         outline[1] = '\0';
-        
+
         /* Draw morse code table with code descriptions. */
         for (i = 0; morse_alphabets[i] != '\0'; i++) {
             int morse_code;
@@ -1024,7 +1024,7 @@ static void kbd_draw_picker(struct keyboard_parameters *pm,
         /* draw page */
         int i, j;
         int w, h;
-        unsigned short ch;
+        ucschar_t ch;
         unsigned char *utf8;
 
         sc->setfont(pm->curfont);
@@ -1071,7 +1071,7 @@ static void kbd_draw_edit_line(struct keyboard_parameters *pm,
     int sc_w = vp->width;
     int y = (vp->height - pm->font_h) / 2;
 
-    
+
     int text_margin = (sc_w - pm->text_w * pm->max_chars_text) / 2;
 
 #if 0
@@ -1265,12 +1265,12 @@ static void kbd_insert_selected(struct keyboard_parameters *pm,
                                 struct edit_state *state)
 {
     /* find input char */
-    unsigned short ch = get_kbd_ch(pm, pm->x, pm->y);
+    ucschar_t ch = get_kbd_ch(pm, pm->x, pm->y);
 
     /* check for hangul input */
     if (ch >= 0x3131 && ch <= 0x3163)
     {
-        unsigned short tmp;
+        ucschar_t tmp;
 
         if (!state->hangul)
         {
@@ -1335,7 +1335,7 @@ static void kbd_insert_selected(struct keyboard_parameters *pm,
 
 static void kbd_backspace(struct edit_state *state)
 {
-    unsigned short ch;
+    ucschar_t ch;
     if (state->hangul)
     {
         if (state->htail)
diff --git a/bootloader/iriver_h1x0.c b/bootloader/iriver_h1x0.c
index 502143ce58..1bf41b5a8c 100644
--- a/bootloader/iriver_h1x0.c
+++ b/bootloader/iriver_h1x0.c
@@ -600,16 +600,16 @@ int usb_screen(void)
    return 0;
 }
 
-unsigned short *bidi_l2v(const unsigned char *str, int orientation)
+ucschar_t *bidi_l2v(const unsigned char *str, int orientation)
 {
-    static unsigned short utf16_buf[SCROLL_LINE_SIZE];
-    unsigned short *target;
+    static ucschar_t utf_buf[SCROLL_LINE_SIZE];
+    ucschar_t *target;
     (void)orientation;
 
-    target = utf16_buf;
+    target = utf_buf;
 
     while (*str)
         str = utf8decode(str, target++);
     *target = 0;
-    return utf16_buf;
+    return utf_buf;
 }
diff --git a/bootloader/iriver_h300.c b/bootloader/iriver_h300.c
index 3cb06ca5c6..7ba78f9d7f 100644
--- a/bootloader/iriver_h300.c
+++ b/bootloader/iriver_h300.c
@@ -660,16 +660,16 @@ int usb_screen(void)
    return 0;
 }
 
-unsigned short *bidi_l2v(const unsigned char *str, int orientation)
+ucschar_t *bidi_l2v(const unsigned char *str, int orientation)
 {
-    static unsigned short utf16_buf[SCROLL_LINE_SIZE];
-    unsigned short *target;
+    static ucschar_t utf_buf[SCROLL_LINE_SIZE];
+    ucschar_t *target;
     (void)orientation;
 
-    target = utf16_buf;
+    target = utf_buf;
 
     while (*str)
         str = utf8decode(str, target++);
     *target = 0;
-    return utf16_buf;
+    return utf_buf;
 }
diff --git a/docs/PLUGIN_API b/docs/PLUGIN_API
index 915d26119b..961d3da2b8 100644
--- a/docs/PLUGIN_API
+++ b/docs/PLUGIN_API
@@ -225,7 +225,7 @@ void beep_play(unsigned int frequency, unsigned int duration, unsigned int ampli
     \param amplitude
     \description
 
-unsigned short *bidi_l2v( const unsigned char *str, int orientation )
+ucschar_t *bidi_l2v( const unsigned char *str, int orientation )
     \param str
     \param orientation
     \return
@@ -407,13 +407,13 @@ const struct cbmp_bitmap_info_entry *core_bitmaps
     \return
     \description
 
-const unsigned char *font_get_bits( struct font *pf, unsigned short char_code )
+const unsigned char *font_get_bits( struct font *pf, ucschar_t char_code )
     \param pf
     \param char_code
     \return
     \description
 
-const unsigned char* utf8decode(const unsigned char *utf8, unsigned short *ucs)
+const unsigned char* utf8decode(const unsigned char *utf8, ucschar_t *ucs)
     \group unicode stuff
     \param utf8
     \param ucs
@@ -747,7 +747,7 @@ int font_getstringsize(const unsigned char *str, int *w, int *h, int fontnumber)
     \return
     \description
 
-int font_get_width(struct font* pf, unsigned short char_code)
+int font_get_width(struct font* pf, ucschar_t char_code)
     \param pf
     \param char_code
     \return
@@ -972,7 +972,7 @@ bool is_diacritic(const unsigned short char_code, bool *is_rtl)
     \return
     \description
 
-int kbd_input(char* buffer, int buflen, unsigned short *kbd)
+int kbd_input(char* buffer, int buflen, ucschar_t *kbd)
     \group misc
     \param buffer
     \param buflen
diff --git a/firmware/arabjoin.h b/firmware/arabjoin.h
index 0085b31f4c..5db6b4d79a 100644
--- a/firmware/arabjoin.h
+++ b/firmware/arabjoin.h
@@ -1,3 +1,5 @@
+/* Note these are not ucschar_t becuase all arabic
+   codepoints are <16bit, so no need to waste table space */
 typedef struct {
     unsigned short isolated;
     unsigned short final;
diff --git a/firmware/bidi.c b/firmware/bidi.c
index c19412693e..310de36c91 100644
--- a/firmware/bidi.c
+++ b/firmware/bidi.c
@@ -44,7 +44,7 @@
 #define XOR(a,b) ((a||b) && !(a&&b))
 
 #ifndef BOOTLOADER
-static const arab_t * arab_lookup(unsigned short uchar)
+static const arab_t * arab_lookup(ucschar_t uchar)
 {
     if (uchar >= 0x621 && uchar <= 0x63a)
         return &(jointable[uchar - 0x621]);
@@ -57,15 +57,15 @@ static const arab_t * arab_lookup(unsigned short uchar)
     return 0;
 }
 
-static void arabjoin(unsigned short * stringprt, int length)
+static void arabjoin(ucschar_t *stringprt, int length)
 {
     bool connected = false;
-    unsigned short * writeprt = stringprt;
+    ucschar_t *writeprt = stringprt;
 
     const arab_t * prev = 0;
     const arab_t * cur;
     const arab_t * ligature = 0;
-    short uchar;
+    ucschar_t uchar;
 
     int i;
     for (i = 0; i <= length; i++) {
@@ -135,13 +135,13 @@ static void arabjoin(unsigned short * stringprt, int length)
 }
 #endif /* !BOOTLOADER */
 
-unsigned short *bidi_l2v(const unsigned char *str, int orientation)
+ucschar_t *bidi_l2v(const unsigned char *str, int orientation)
 {
-    static unsigned short  utf16_buf[SCROLL_LINE_SIZE];
-    unsigned short *target, *tmp;
+    static ucschar_t utf_buf[SCROLL_LINE_SIZE];
+    ucschar_t *target, *tmp;
 #ifndef BOOTLOADER
-    static unsigned short  bidi_buf[SCROLL_LINE_SIZE];
-    unsigned short *heb_str; /* *broken_str */
+    static ucschar_t bidi_buf[SCROLL_LINE_SIZE];
+    ucschar_t *heb_str; /* *broken_str */
     int block_start, block_end, block_type, block_length, i;
     int length = utf8length(str);
     length=length>=SCROLL_LINE_SIZE?SCROLL_LINE_SIZE-1:length;
@@ -152,21 +152,21 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
 
     tmp = str;
     */
-    target = tmp = utf16_buf;
-    while (*str && target < &utf16_buf[SCROLL_LINE_SIZE-1])
+    target = tmp = utf_buf;
+    while (*str && target < &utf_buf[SCROLL_LINE_SIZE-1])
         str = utf8decode(str, target++);
     *target = 0;
 
 #ifdef BOOTLOADER
     (void)orientation;
-    return utf16_buf;
-    
+    return utf_buf;
+
 #else /* !BOOTLOADER */
-    if (target == utf16_buf) /* empty string */
+    if (target == utf_buf) /* empty string */
         return target;
 
     /* properly join any arabic chars */
-    arabjoin(utf16_buf, length);
+    arabjoin(utf_buf, length);
 
     block_start=block_end=block_length=0;
 
@@ -204,7 +204,7 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
 
         for (i=block_start; i<=block_end; i++) {
             *target = (block_type == orientation) ?
-                      *(utf16_buf+i) : *(utf16_buf+block_end-i+block_start);
+                      *(utf_buf+i) : *(utf_buf+block_end-i+block_start);
             if (block_type!=orientation) {
                 switch (*target) {
                 case '(':
@@ -226,7 +226,7 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
     *target = 0;
 
 #if 0 /* Is this code really necessary? */
-    broken_str = utf16_buf;
+    broken_str = utf_buf;
     begin=end=length-1;
     target = broken_str;
 
@@ -246,7 +246,7 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
         if (char_count==max_chars) { /* try to avoid breaking words */
             int new_char_count = char_count;
             int new_begin = begin;
-            
+
             while (new_char_count>0) {
                 if (_isblank(heb_str[new_begin]) ||
                     _isnewline(heb_str[new_begin])) {
@@ -261,11 +261,11 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
             }
         }
         orig_begin=begin;
-        
+
         /* if (_isblank(heb_str[begin])) {
             heb_str[begin]='\n';
         } */
-        
+
         /* skip leading newlines */
         while (begin<=end && _isnewline(heb_str[begin])) {
             begin++;
@@ -282,7 +282,7 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
             target++;
         }
         begin=orig_begin;
-        
+
         if (begin<=0) {
             *target = 0;
             break;
@@ -295,4 +295,3 @@ unsigned short *bidi_l2v(const unsigned char *str, int orientation)
     return heb_str;
 #endif /* !BOOTLOADER */
 }
-
diff --git a/firmware/common/diacritic.c b/firmware/common/diacritic.c
index 7a0d97b79b..68c8dcd4c9 100644
--- a/firmware/common/diacritic.c
+++ b/firmware/common/diacritic.c
@@ -28,8 +28,8 @@
 #include "system.h"
 
 #define DIAC_NUM_RANGES      (ARRAYLEN(diac_ranges))
-#define DIAC_RTL             (1 << 7)
-#define DIAC_CNT             (0xFF ^ DIAC_RTL)
+#define DIAC_RTL             (1 << 15)
+#define DIAC_CNT             (0xFFFF ^ DIAC_RTL)
 
 /* Each diac_range_ struct defines a Unicode range that begins with
  * N diacritic characters, and continues with non-diacritic characters up to the
@@ -39,8 +39,8 @@
 
 struct diac_range
 {
-    uint16_t base;
-    uint8_t  info; /* [RTL:1 CNT:7] */
+    uint16_t base; /* Not ucschar_t until we need >16b */
+    uint16_t info; /* [RTL:1 CNT:15] */
 };
 
 #define DIAC_RANGE_ENTRY(first_diac, first_non_diac, is_rtl) \
@@ -51,7 +51,7 @@ struct diac_range
 static const struct diac_range diac_ranges[] =
 {
     DIAC_RANGE_ENTRY(0x0000, 0x0000, 0),
-    DIAC_RANGE_ENTRY(FIRST_DIACRITIC, 0x0370, 0),
+    DIAC_RANGE_ENTRY(FIRST_DIACRITIC, 0x0370, 0), /* v1 - v4.1 */
     DIAC_RANGE_ENTRY(0x0483, 0x048a, 0),
     DIAC_RANGE_ENTRY(0x0591, 0x05be, 1),
     DIAC_RANGE_ENTRY(0x05bf, 0x05c0, 1),
@@ -146,6 +146,7 @@ static const struct diac_range diac_ranges[] =
     DIAC_RANGE_ENTRY(0x19c8, 0x19ca, 0),
     DIAC_RANGE_ENTRY(0x1a17, 0x1a1c, 0),
     DIAC_RANGE_ENTRY(0x1a55, 0x1a80, 0),
+    DIAC_RANGE_ENTRY(0x1ab0, 0x1b00, 0), /* v7.0 */
     DIAC_RANGE_ENTRY(0x1b00, 0x1b05, 0),
     DIAC_RANGE_ENTRY(0x1b34, 0x1b45, 0),
     DIAC_RANGE_ENTRY(0x1b6b, 0x1b74, 0),
@@ -156,10 +157,10 @@ static const struct diac_range diac_ranges[] =
     DIAC_RANGE_ENTRY(0x1cd4, 0x1ce9, 0),
     DIAC_RANGE_ENTRY(0x1ced, 0x1cee, 0),
     DIAC_RANGE_ENTRY(0x1cf2, 0x1cf3, 0),
-    DIAC_RANGE_ENTRY(0x1dc0, 0x1e00, 0),
-    DIAC_RANGE_ENTRY(0x20d0, 0x20f1, 0),
+    DIAC_RANGE_ENTRY(0x1dc0, 0x1e00, 0), /* v4.1 - v5.2 */
+    DIAC_RANGE_ENTRY(0x20d0, 0x2100, 0), /* v1.0 - v5.1 */
     DIAC_RANGE_ENTRY(0x2cef, 0x2cf2, 0),
-    DIAC_RANGE_ENTRY(0x2de0, 0x2e00, 0),
+    DIAC_RANGE_ENTRY(0x2de0, 0x2e00, 0), /* v5.1 */
     DIAC_RANGE_ENTRY(0x302a, 0x3030, 0),
     DIAC_RANGE_ENTRY(0x3099, 0x309b, 0),
     DIAC_RANGE_ENTRY(0xa66f, 0xa673, 0),
@@ -188,7 +189,7 @@ static const struct diac_range diac_ranges[] =
     DIAC_RANGE_ENTRY(0xabe3, 0xabeb, 0),
     DIAC_RANGE_ENTRY(0xabec, 0xabee, 0),
     DIAC_RANGE_ENTRY(0xfb1e, 0xfb1f, 0),
-    DIAC_RANGE_ENTRY(0xfe20, 0xfe27, 0),
+    DIAC_RANGE_ENTRY(0xfe20, 0xfe30, 0), /* v1.0 - v8.0 */
     DIAC_RANGE_ENTRY(0xfe70, 0xfe70, 1),
     DIAC_RANGE_ENTRY(0xff00, 0xff00, 0),
     DIAC_RANGE_ENTRY(0xffff, 0xffff, 0),
@@ -196,7 +197,7 @@ static const struct diac_range diac_ranges[] =
 
 #define MRU_MAX_LEN 32
 
-bool is_diacritic(const unsigned short char_code, bool *is_rtl)
+bool is_diacritic(const ucschar_t char_code, bool *is_rtl)
 {
     static uint8_t mru_len = 0;
     static uint8_t diacritic_mru[MRU_MAX_LEN];
@@ -209,7 +210,6 @@ bool is_diacritic(const unsigned short char_code, bool *is_rtl)
     /* Search in MRU */
     for (mru = 0, i = 0; mru < mru_len; mru++)
     {
-
         /* Items shifted >> 1 */
         itmp = i;
         i = diacritic_mru[mru];
@@ -250,10 +250,10 @@ Found:
     if (is_rtl)
         *is_rtl = ((DIAC_RTL & info) == DIAC_RTL);
 
-    return (char_code < diac->base + (info & DIAC_CNT));
+    return (char_code < (diac->base + (info & DIAC_CNT)));
 }
 #else /*BOOTLOADER*/
-inline bool is_diacritic(const unsigned short char_code, bool *is_rtl)
+inline bool is_diacritic(const ucschar_t char_code, bool *is_rtl)
 {
     (void)char_code;
     if (is_rtl)
diff --git a/firmware/common/unicode.c b/firmware/common/unicode.c
index 444ea0f406..c1e187a709 100644
--- a/firmware/common/unicode.c
+++ b/firmware/common/unicode.c
@@ -127,7 +127,7 @@ static int volatile cp_table_ref = 0;
 
 /* non-default codepage table buffer (cannot be bufalloced! playback itself
    may be making the load request) */
-static unsigned short codepage_table[MAX_CP_TABLE_SIZE+1];
+static unsigned short codepage_table[MAX_CP_TABLE_SIZE+1]; // XXX convert to ucschar_t if we ever need > 16bit mappings?
 
 #if defined(APPLICATION) && defined(__linux__)
 static const char * const name_codepages_linux[NUM_CODEPAGES+1] =
@@ -344,7 +344,7 @@ unsigned char* iso_decode_ex(const unsigned char *iso, unsigned char *utf8, int
     cp_lock_leave();
 
     while (count-- && utf8_size > 0) {
-        unsigned short ucs, tmp;
+        ucschar_t ucs, tmp;
 
         if (*iso < 128 || cp == UTF_8) /* Already UTF-8 */
         {
@@ -511,8 +511,25 @@ unsigned long utf8length(const unsigned char *utf8)
     return l;
 }
 
+/* Take a utf8 string and return the encoded length in utf16 code units */
+unsigned long utf16len_utf8(const unsigned char *utf8)
+{
+    ucschar_t cp;
+    unsigned long length = 0;
+    while (*utf8) {
+        utf8 = utf8decode(utf8, &cp);
+#ifdef UNICODE32
+        if (cp >= 0x10000)
+            length++;
+#endif
+        length++;
+    }
+
+    return length;
+}
+
 /* Decode 1 UTF-8 char and return a pointer to the next char. */
-const unsigned char* utf8decode(const unsigned char *utf8, unsigned short *ucs)
+const unsigned char* utf8decode(const unsigned char *utf8, ucschar_t *ucs)
 {
     unsigned char c = *utf8++;
     unsigned long code;
@@ -552,8 +569,16 @@ const unsigned char* utf8decode(const unsigned char *utf8, unsigned short *ucs)
         /* Invalid UTF-8 char */
         code = 0xfffd;
     }
-    /* currently we don't support chars above U-FFFF */
-    *ucs = (code < 0x10000) ? code : 0xfffd;
+
+#ifdef UNICODE32
+    if (code > 0x10ffff)
+        code = 0xfffd;
+#else
+    if (code > 0xffff)
+        code = 0xfffd;
+#endif
+
+    *ucs = code;
     return utf8;
 }
 
diff --git a/firmware/drivers/fat.c b/firmware/drivers/fat.c
index 460b6d8a39..b67b3062ee 100644
--- a/firmware/drivers/fat.c
+++ b/firmware/drivers/fat.c
@@ -747,6 +747,8 @@ static bool fatlong_parse_entry(struct fatlong_parse_state *lnparse,
     /* so far so good; save entry information */
     lnparse->ord = ord;
 
+    /* Treat entries as opaque 16-bit values;
+       utf8decode happens in fatlong_parse_finish() */
     uint16_t *ucsp = fatent->ucssegs[ord - 1 + 5];
     unsigned int i = longent_char_first();
 
@@ -797,13 +799,24 @@ static bool fatlong_parse_finish(struct fatlong_parse_state *lnparse,
     /* ensure the last segment is NULL-terminated if it is filled */
     fatent->ucssegs[lnparse->ord_max + 5][0] = 0x0000;
 
-    for (uint16_t *ucsp = fatent->ucssegs[5], ucc = *ucsp;
-         ucc; ucc = *++ucsp)
+    unsigned long ucc;     /* Decoded codepoint */
+    uint16_t *ucsp, ucs;
+    for (ucsp = fatent->ucssegs[5], ucs=*ucsp; ucs; ucs = *++ucsp)
     {
         /* end should be hit before ever seeing padding */
-        if (ucc == 0xffff)
+        if (ucs == 0xffff)
             return false;
 
+#ifdef UNICODE32
+        /* Check for a surrogate UTF16 pair */
+        if (ucs >= 0xd800 && ucs < 0xdc00 &&
+            *(ucsp+1) >= 0xdc00 && *(ucsp+1) < 0xe000) {
+            ucc = 0x10000 + (((ucs & 0x3ff) << 10) | (*(ucsp+1) & 0x3ff));
+            ucsp++;
+        } else
+#endif
+            ucc = ucs;
+
         if ((p = utf8encode(ucc, p)) - name > FAT_DIRENTRY_NAME_MAX)
             return false;
     }
@@ -1612,12 +1625,27 @@ static int write_longname(struct bpb *fat_bpb, struct fat_filestr *parentstr,
 
     for (unsigned long i = 0; i < ucspadlen; i++)
     {
-        if (i < ucslen)
+        if (i < ucslen) {
+#ifdef UNICODE32
+            ucschar_t tmp;
+            name = utf8decode(name, &tmp);
+            /* For codepoints > U+FFFF we will need to use a UTF16 surrogate
+               pair. 'ucslen' already takes this into account! */
+            if (tmp < 0x10000) {
+                ucsname[i] = tmp;
+            } else {
+                tmp -= 0x10000;
+                ucsname[i++] = 0xd800 | ((tmp >> 10) & 0x3ff); /* High */
+                ucsname[i] = 0xdc00 | (tmp & 0x3ff); /* Low */
+            }
+#else
             name = utf8decode(name, &ucsname[i]);
-        else if (i == ucslen)
+#endif
+        } else if (i == ucslen) {
             ucsname[i] = 0x0000; /* name doesn't fill last block */
-        else /* i > ucslen */
+        } else /* i > ucslen */ {
             ucsname[i] = 0xffff; /* pad-out to end */
+        }
     }
 
     dc_lock_cache();
@@ -1744,9 +1772,12 @@ static int add_dir_entry(struct bpb *fat_bpb, struct fat_filestr *parentstr,
         create_dos_name(basisname, name, &n);
         randomize_dos_name(shortname, basisname, &n);
 
-        /* one dir entry needed for every 13 characters of filename,
-           plus one entry for the short name */
-        ucslen = utf8length(name);
+        /* one dir entry needed for every 13 utf16 "code units"
+           of filename, plus one entry for the short name.
+           Keep in mind that a unicode character can take up to
+           two code units!
+        */
+        ucslen = utf16len_utf8(name);
         if (ucslen > 255)
             FAT_ERROR(-2); /* name is too long */
 
diff --git a/firmware/drivers/lcd-bitmap-common.c b/firmware/drivers/lcd-bitmap-common.c
index ac032e815a..e57ab97611 100644
--- a/firmware/drivers/lcd-bitmap-common.c
+++ b/firmware/drivers/lcd-bitmap-common.c
@@ -385,7 +385,7 @@ static void LCDFN(mono_bmp_part_helper)(const unsigned char *src, int src_x,
 /* put a string at a given pixel position, skipping first ofs pixel columns */
 static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
 {
-    unsigned short *ucs;
+    ucschar_t *ucs;
     struct viewport *vp = LCDFN(current_viewport);
     font_lock(vp->font, true);
     struct font* pf = font_get(vp->font);
@@ -429,7 +429,7 @@ static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
         bool is_rtl, is_diac;
         const unsigned char *bits;
         int width, base_width, base_ofs = 0;
-        const unsigned short next_ch = ucs[1];
+        const ucschar_t next_ch = ucs[1];
 
         if (x >= vp->width)
             break;
@@ -447,7 +447,7 @@ static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
             {
                 if (!rtl_next_non_diac_width)
                 {
-                    const unsigned short *u;
+                    const ucschar_t *u;
 
                     /* Jump to next non-diacritic char, and calc its width */
                     for (u = &ucs[1]; *u && IS_DIACRITIC(*u); u++);
@@ -529,7 +529,7 @@ static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
 /* put a string at a given pixel position, skipping first ofs pixel columns */
 static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
 {
-    unsigned short *ucs;
+    ucschar_t *ucs;
     struct viewport *vp = LCDFN(current_viewport);
     struct font* pf = font_get(vp->font);
     const unsigned char *bits;
@@ -567,7 +567,7 @@ static void LCDFN(putsxyofs)(int x, int y, int ofs, const unsigned char *str)
     /* allow utf but no diacritics or rtl lang */
     for (ucs = bidi_l2v(str, 1); *ucs; ucs++)
     {
-        const unsigned short next_ch = ucs[1];
+        const ucschar_t next_ch = ucs[1];
 
         if (x >= vp->width)
             break;
diff --git a/firmware/export/bidi.h b/firmware/export/bidi.h
index 14a09b5105..dc52e8671e 100644
--- a/firmware/export/bidi.h
+++ b/firmware/export/bidi.h
@@ -21,6 +21,6 @@
 #ifndef BIDI_H
 #define BIDI_H
 
-extern unsigned short *bidi_l2v(const unsigned char *str, int orientation);
+ucschar_t *bidi_l2v(const unsigned char *str, int orientation);
 
 #endif /* BIDI_H */
diff --git a/firmware/export/config.h b/firmware/export/config.h
index 54107d5a31..245777a671 100644
--- a/firmware/export/config.h
+++ b/firmware/export/config.h
@@ -1461,4 +1461,11 @@ Lyre prototype 1 */
 #error "HAVE_LCD_SLEEP_SETTING requires HAVE_LCD_SLEEP"
 #endif
 
+// XXX Figure out a better place to put this?
+#ifdef UNICODE32
+#define ucschar_t unsigned int
+#else
+#define ucschar_t unsigned short
+#endif
+
 #endif /* __CONFIG_H__ */
diff --git a/firmware/export/cpu.h b/firmware/export/cpu.h
index 701baa9e78..5cd875c351 100644
--- a/firmware/export/cpu.h
+++ b/firmware/export/cpu.h
@@ -18,6 +18,9 @@
  * KIND, either express or implied.
  *
  ****************************************************************************/
+#ifndef __CPU_H
+#define __CPU_H
+
 #include "config.h"
 
 #if CONFIG_CPU == MCF5249
@@ -80,3 +83,5 @@
 #if CONFIG_CPU == STM32H743
 #include "cpu-stm32h743.h"
 #endif
+
+#endif /* __CPU_H */
diff --git a/firmware/export/font.h b/firmware/export/font.h
index 2334a8bd1a..604635f985 100644
--- a/firmware/export/font.h
+++ b/firmware/export/font.h
@@ -86,7 +86,7 @@ struct font {
     int          maxwidth;        /* max width in pixels*/
     unsigned int height;          /* height in pixels*/
     int          ascent;          /* ascent (baseline) height*/
-    int          firstchar;       /* first character in bitmap*/
+    unsigned int firstchar;       /* first character in bitmap*/
     int          size;            /* font size in glyphs*/
     int          depth;           /* depth of the font, 0=1bit and 1=4bit */
     const unsigned char *bits;    /* 8-bit column bitmap data*/
@@ -95,24 +95,24 @@ struct font {
     const unsigned char *width;   /* character widths or NULL if fixed*/
     int          defaultchar;     /* default char (not glyph index)*/
     int32_t      bits_size;       /* # bytes of glyph bits*/
-    
+
     /* file, buffer and cache management */
     int          fd;              /* fd for the font file. >= 0 if cached */
     int          fd_width;        /* fd for the font file. >= 0 if cached */
-    int          fd_offset;       /* fd for the font file. >= 0 if cached */    
+    int          fd_offset;       /* fd for the font file. >= 0 if cached */
     int          handle;          /* core_allocator handle */
-    unsigned char *buffer_start;    /* buffer to store the font in */       
-    unsigned char *buffer_position; /* position in the buffer */    
+    unsigned char *buffer_start;    /* buffer to store the font in */
+    unsigned char *buffer_position; /* position in the buffer */
     unsigned char *buffer_end;      /* end of the buffer */
     size_t         buffer_size;     /* size of the buffer in bytes */
     bool         disabled;        /* font disabled (use blank as fallback if not in cache) */
-#ifndef __PCTOOL__    
+#ifndef __PCTOOL__
     struct font_cache cache;
     uint32_t file_width_offset;    /* offset to file width data    */
     uint32_t file_offset_offset;   /* offset to file offset data   */
     int long_offset;
-#endif    
-    
+#endif
+
 };
 
 /* font routines*/
@@ -134,7 +134,7 @@ void font_enable_all(void);
 struct font* font_get(int font);
 int font_getstringnsize(const unsigned char *str, size_t maxbytes, int *w, int *h, int fontnumber);
 int font_getstringsize(const unsigned char *str, int *w, int *h, int fontnumber);
-int font_get_width(struct font* ft, unsigned short ch);
-const unsigned char * font_get_bits(struct font* ft, unsigned short ch);
+int font_get_width(struct font* ft, ucschar_t ch);
+const unsigned char * font_get_bits(struct font* ft, ucschar_t ch);
 
 #endif
diff --git a/firmware/export/hangul.h b/firmware/export/hangul.h
index ca2b4ee079..30883a13b4 100644
--- a/firmware/export/hangul.h
+++ b/firmware/export/hangul.h
@@ -21,5 +21,4 @@
 
 extern const char jamo_table[51][3];
 
-unsigned short hangul_join(unsigned short lead, unsigned short vowel,
-                                unsigned short tail);
+ucschar_t hangul_join(ucschar_t lead, ucschar_t vowel, ucschar_t tail);
diff --git a/firmware/font.c b/firmware/font.c
index f8a755168e..0f11ea5a0a 100644
--- a/firmware/font.c
+++ b/firmware/font.c
@@ -53,6 +53,12 @@
 #define FONT_EXT "fnt"
 #define GLYPH_CACHE_EXT "gc"
 
+#ifdef UNICODE32
+#define FC_HEADER_VAL 0x01000020
+#else
+#define FC_HEADER_VAL 0x01000010
+#endif
+
 /* max static loadable font buffer size */
 #ifndef MAX_FONT_SIZE
 #if LCD_HEIGHT > 64
@@ -182,7 +188,7 @@ void font_init(void)
 
 static short readshort(struct font *pf)
 {
-    unsigned short s;
+    uint16_t s;
 
     s = *pf->buffer_position++ & 0xff;
     s |= (*pf->buffer_position++ << 8);
@@ -361,8 +367,8 @@ static size_t font_glyphs_to_bufsize(struct font *pf, int glyphs)
     size_t bufsize;
 
     /* LRU bytes per glyph */
-    bufsize = LRU_SLOT_OVERHEAD + sizeof(struct font_cache_entry) + 
-        sizeof( unsigned short);
+    bufsize = LRU_SLOT_OVERHEAD + sizeof(struct font_cache_entry) +
+        sizeof(unsigned short);
     /* Image bytes per glyph */
     bufsize += glyph_bytes(pf, pf->maxwidth);
     bufsize *= glyphs;
@@ -371,7 +377,7 @@ static size_t font_glyphs_to_bufsize(struct font *pf, int glyphs)
 }
 
 static struct font* font_load_header(int fd, struct font *pheader,
-                                     struct font *pf, 
+                                     struct font *pf,
                                      uint32_t *nwidth, uint32_t *noffset)
 {
     /* Load the header. Readshort() and readlong()              *
@@ -420,16 +426,24 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
     if ( fd < 0 )
         return -1;
 
+#ifdef UNICODE32
+    if (glyphs && glyphs < 3)
+        glyphs = 3; /* Guarantee we'll always have at least 2 after alignment */
+#else
+    if (glyphs && glyphs < 2)
+        glyphs = 2; /* Guarantee we'll always have at least 1 after alignment */
+#endif
+
     /* load font struct f with file header */
     int file_size = filesize( fd );
     struct font header;
     struct font f;
 
-    uint32_t nwidth, noffset;     
+    uint32_t nwidth, noffset;
     if ( !font_load_header( fd, &header, &f, &nwidth, &noffset )
 #if LCD_DEPTH < 16
         || f.depth
-#endif  
+#endif
     )
     {
         close(fd);
@@ -458,7 +472,7 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
         cached = true;
     else
         bufsize = file_size;
-    
+
     /* check already loaded */
     int font_id = find_font_index(path);
 
@@ -503,7 +517,7 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
                 return -1;
         }
         pd->refcount++;
-        //printf("reusing handle %d for %s (count: %d)\n", font_id, path, pd->refcount); 
+        //printf("reusing handle %d for %s (count: %d)\n", font_id, path, pd->refcount);
         close(fd);
         return font_id;
     }
@@ -522,7 +536,7 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
         return -1;
     font_id = open_slot;
     size_t path_bufsz = MAX(path_len + 1, 64); /* enough size for common case */
-    /* allocate mem */    
+    /* allocate mem */
     int handle = core_alloc_ex(
                      bufsize + path_bufsz + sizeof( struct buflib_alloc_data ),
                      &buflibops );
@@ -574,7 +588,7 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
         pf->fd_offset = -1;
     }
     else
-    {           
+    {
         lseek( fd, 0, SEEK_SET);
         read(fd, pf->buffer_start, pf->buffer_size);
 
@@ -723,7 +737,7 @@ load_cache_entry(struct font_cache_entry* p, void* callback_data)
 {
     struct font* pf = callback_data;
 
-    unsigned short char_code = p->_char_code;
+    ucschar_t char_code = p->_char_code;
     int fd;
 
     lock_font_handle(pf->handle, true);
@@ -788,7 +802,7 @@ static void cache_create(struct font* pf)
      * when the font file is closed during USB */
     unsigned char *cache_buf = pf->buffer_start + bitmap_size;
     size_t cache_size = pf->buffer_size - bitmap_size;
-    ALIGN_BUFFER(cache_buf, cache_size, 2);
+    ALIGN_BUFFER(cache_buf, cache_size, sizeof(ucschar_t));
     memset(pf->buffer_start, 0, bitmap_size);
     /* Initialise cache */
     font_cache_create(&pf->cache, cache_buf, cache_size, bitmap_size);
@@ -797,7 +811,7 @@ static void cache_create(struct font* pf)
 /*
  * Returns width of character
  */
-int font_get_width(struct font* pf, unsigned short char_code)
+int font_get_width(struct font* pf, ucschar_t char_code)
 {
     int width;
     struct font_cache_entry *e;
@@ -820,7 +834,7 @@ int font_get_width(struct font* pf, unsigned short char_code)
     return width;
 }
 
-const unsigned char* font_get_bits(struct font* pf, unsigned short char_code)
+const unsigned char* font_get_bits(struct font* pf, ucschar_t char_code)
 {
     const unsigned char* bits;
 
@@ -831,7 +845,7 @@ const unsigned char* font_get_bits(struct font* pf, unsigned short char_code)
 
     if (pf->fd >= 0 && pf != &sysfont)
     {
-        bits = 
+        bits =
             (unsigned char*)font_cache_get(&pf->cache, char_code,
                                 false, load_cache_entry, pf)->bitmap;
     }
@@ -884,7 +898,7 @@ static void glyph_file_write(void* data)
 {
     struct font_cache_entry* p = data;
     struct font* pf = cache_pf;
-    unsigned short ch;
+    ucschar_t ch;
     static int buffer_pos = 0;
 #define WRITE_BUFFER 256
     static unsigned char buffer[WRITE_BUFFER];
@@ -899,11 +913,19 @@ static void glyph_file_write(void* data)
     }
     if ( p->_char_code == 0xffff )
         return;
-    
+
     ch = p->_char_code + pf->firstchar;
-    buffer[buffer_pos] = ch >> 8;
+#ifdef UNICODE32
+    buffer[buffer_pos] = (ch >> 24) & 0xff;
+    buffer[buffer_pos+1] = (ch >> 16) & 0xff;
+    buffer[buffer_pos+2] = (ch >> 8) & 0xff;
+    buffer[buffer_pos+3] = ch & 0xff;
+    buffer_pos += 4;
+#else
+    buffer[buffer_pos] = (ch >> 8) & 0xff;
     buffer[buffer_pos+1] = ch & 0xff;
     buffer_pos += 2;
+#endif
     return;
 }
 
@@ -928,11 +950,13 @@ static void glyph_cache_save(int font_id)
         fd = open(filename, O_WRONLY|O_CREAT|O_TRUNC, 0666);
         if (fd >= 0)
         {
+            uint32_t header = FC_HEADER_VAL;
+            write(fd, &header, sizeof(header));
             cache_pf = pf;
             cache_fd = fd;
             lru_traverse(&cache_pf->cache._lru, glyph_file_write);
             glyph_file_write(NULL);
-            if (cache_fd >= 0) 
+            if (cache_fd >= 0)
             {
                 close(cache_fd);
                 cache_fd = -1;
@@ -944,9 +968,9 @@ static void glyph_cache_save(int font_id)
 }
 
 
-static int ushortcmp(const void *a, const void *b)
+static int ucscharcmp(const void *a, const void *b)
 {
-    return ((int)(*(unsigned short*)a - *(unsigned short*)b));
+    return ((int)(*(ucschar_t*)a - *(ucschar_t*)b));
 }
 
 static NO_INLINE void glyph_cache_load(const char *font_path, struct font *pf)
@@ -954,13 +978,13 @@ static NO_INLINE void glyph_cache_load(const char *font_path, struct font *pf)
 #define MAX_SORT 256
     if (pf->fd >= 0) {
         int i, size, fd;
-        unsigned char tmp[2];
-        unsigned short ch;
-        unsigned short glyphs[MAX_SORT];
-        unsigned short glyphs_lru_order[MAX_SORT];
-        int glyph_file_skip=0, glyph_file_size=0;
-        
-        int sort_size = pf->cache._capacity;        
+        unsigned char tmp[sizeof(ucschar_t)];
+        ucschar_t ch;
+        ucschar_t glyphs[MAX_SORT];
+        ucschar_t glyphs_lru_order[MAX_SORT];
+        unsigned int glyph_file_skip=0, glyph_file_size=0;
+
+        int sort_size = pf->cache._capacity;
         if ( sort_size > MAX_SORT )
              sort_size = MAX_SORT;
 
@@ -974,31 +998,41 @@ static NO_INLINE void glyph_cache_load(const char *font_path, struct font *pf)
             fd = open(GLYPH_CACHE_FILE, O_RDONLY|O_BINARY);
 #endif
         if (fd >= 0) {
+            /* Header */
+            uint32_t hdr = 0;
+            read(fd, &hdr, sizeof(hdr));
+            if (hdr != FC_HEADER_VAL)
+                goto latin;
             /* only read what fits */
             glyph_file_size = filesize( fd );
-            if ( glyph_file_size > 2*pf->cache._capacity ) {
-                glyph_file_skip = glyph_file_size - 2*pf->cache._capacity;
-                lseek( fd, glyph_file_skip, SEEK_SET );
+            if (glyph_file_size < sizeof(uint32_t))
+                goto latin;
+            glyph_file_size -= sizeof(uint32_t);
+            if ( glyph_file_size > (int)sizeof(ucschar_t)*pf->cache._capacity ) {
+                glyph_file_skip = glyph_file_size - sizeof(ucschar_t)*pf->cache._capacity;
+                lseek( fd, glyph_file_skip + sizeof(uint32_t), SEEK_SET );
             }
-
             while(1) {
-
                 for ( size = 0;
-                      read( fd, tmp, 2 ) == 2 && size < sort_size;
-                      size++ ) 
+                      read( fd, tmp, sizeof(tmp) ) == sizeof(tmp) && size < sort_size;
+                      size++ )
                 {
+#ifdef UNICODE32
+                    glyphs[size] = (tmp[0] << 24) | (tmp[1] << 16) | (tmp[2] << 8) | tmp[3];
+#else
                     glyphs[size] = (tmp[0] << 8) | tmp[1];
+#endif
                     glyphs_lru_order[size] = glyphs[size];
                 }
-                
+
                 /* sort glyphs array to make sector cache happy */
-                qsort((void *)glyphs, size, sizeof(unsigned short), 
-                      ushortcmp );
+                qsort((void *)glyphs, size, sizeof(ucschar_t),
+                      ucscharcmp );
 
                 /* load font bitmaps */
                 for( i = 0; i < size ; i++ )
-                         font_get_bits(pf, glyphs[i]);
-                
+                    font_get_bits(pf, glyphs[i]);
+
                 /* redo to fix lru order */
                 for ( i = 0; i < size ; i++)
                     font_get_bits(pf, glyphs_lru_order[i]);
@@ -1009,6 +1043,7 @@ static NO_INLINE void glyph_cache_load(const char *font_path, struct font *pf)
 
             close(fd);
         } else {
+        latin:
             /* load latin1 chars into cache */
             for ( ch = 32 ; ch < 256  && ch < pf->cache._capacity + 32; ch++ )
                 font_get_bits(pf, ch);
@@ -1040,7 +1075,7 @@ struct font* font_get(int font)
 /*
  * Returns width of character
  */
-int font_get_width(struct font* pf, unsigned short char_code)
+int font_get_width(struct font* pf, ucschar_t char_code)
 {
     /* check input range*/
     if (char_code < pf->firstchar || char_code >= pf->firstchar+pf->size)
@@ -1050,7 +1085,7 @@ int font_get_width(struct font* pf, unsigned short char_code)
     return pf->width? pf->width[char_code]: pf->maxwidth;
 }
 
-const unsigned char* font_get_bits(struct font* pf, unsigned short char_code)
+const unsigned char* font_get_bits(struct font* pf, ucschar_t char_code)
 {
     const unsigned char* bits;
 
@@ -1079,7 +1114,7 @@ int font_getstringnsize(const unsigned char *str, size_t maxbytes, int *w, int *
 {
     struct font* pf = font_get(fontnum);
     font_lock( fontnum, true );
-    unsigned short ch;
+    ucschar_t ch;
     int width = 0;
     size_t b = maxbytes - 1;
 
diff --git a/firmware/font_cache.c b/firmware/font_cache.c
index 0b03edaf76..536fcfb522 100644
--- a/firmware/font_cache.c
+++ b/firmware/font_cache.c
@@ -43,13 +43,18 @@ void font_cache_create(
     int font_cache_entry_size =
         sizeof(struct font_cache_entry) + bitmap_bytes_size;
 
-    /* make sure font cache entries are a multiple of 16 bits */
-    if (font_cache_entry_size % 2 != 0)
+    /* make sure font cache entries are a multiple of sizeof(ucschar_t) */
+    while (font_cache_entry_size & (sizeof(ucschar_t) -1))
         font_cache_entry_size++;
 
     int cache_size = buf_size /
         (font_cache_entry_size + LRU_SLOT_OVERHEAD + sizeof(short));
 
+#ifdef UNICODE32
+    /* Ensure LRU index size is a multiple of 32 bits */
+    cache_size &= ~1;
+#endif
+
     fcache->_size = 1;
     fcache->_capacity = cache_size;
     fcache->_prev_result = 0;
@@ -72,12 +77,12 @@ void font_cache_create(
 
 /*************************************************************************
  * Binary search that attempts a primary lucky guess that succeeds
- * when there are consecutive codes in the cache between previous 
- * search and new search. Returns a negative of insertion point if 
+ * when there are consecutive codes in the cache between previous
+ * search and new search. Returns a negative of insertion point if
  * not found.
  ************************************************************************/
 static int search(struct font_cache* fcache,
-                  unsigned short char_code,
+                  ucschar_t char_code,
                   int size,
                   int *p_insertion_point )
 {
@@ -85,12 +90,12 @@ static int search(struct font_cache* fcache,
     int left, right, mid=-1, c;
     left = 0;
     right = size;
-    
+
     /* go for a lucky guess */
-    mid = char_code + 
+    mid = char_code +
         fcache->_prev_result - fcache->_prev_char_code;
-            
-    /* check bounds */        
+
+    /* check bounds */
     if ( mid < 0 || mid > right )
             mid = ( left + right ) / 2;
 
@@ -114,7 +119,7 @@ static int search(struct font_cache* fcache,
         mid = (left + right) / 2;
     }
     while (left <= right);
-    
+
     /* not found */
     *p_insertion_point = mid;
     return 0;
@@ -124,7 +129,7 @@ static int search(struct font_cache* fcache,
  ******************************************************************************/
 struct font_cache_entry* font_cache_get(
     struct font_cache* fcache,
-    unsigned short char_code,
+    ucschar_t char_code,
     bool cache_only,
     void (*callback) (struct font_cache_entry* p, void *callback_data),
     void *callback_data)
@@ -132,7 +137,7 @@ struct font_cache_entry* font_cache_get(
     struct font_cache_entry* p;
     int insertion_point;
     int index_to_replace;
-    
+
     /* check bounds */
     p = lru_data(&fcache->_lru, fcache->_index[0]);
     if( char_code < p->_char_code )
@@ -158,14 +163,14 @@ struct font_cache_entry* font_cache_get(
             }
             else
             {
-                p = lru_data(&fcache->_lru, 
+                p = lru_data(&fcache->_lru,
                 fcache->_index[insertion_point+1]);
                 if ( char_code > p->_char_code )
                      insertion_point++;
             }
         }
     }
-    
+
     /* not found */
     if (cache_only)
         return NULL;
diff --git a/firmware/hangul.c b/firmware/hangul.c
index 01c6ba2fab..f171d91486 100644
--- a/firmware/hangul.c
+++ b/firmware/hangul.c
@@ -18,6 +18,7 @@
  * KIND, either express or implied.
  *
  ****************************************************************************/
+#include "config.h"
 #include "hangul.h"
 
 const char jamo_table[51][3] = {
@@ -75,10 +76,9 @@ const char jamo_table[51][3] = {
 };
 
 /* takes three jamo chars and joins them into one hangul */
-unsigned short hangul_join(unsigned short lead, unsigned short vowel,
-                                unsigned short tail)
+ucschar_t hangul_join(ucschar_t lead, ucschar_t vowel, ucschar_t tail)
 {
-    unsigned short ch = 0xfffd;
+    ucschar_t ch = 0xfffd;
 
     if (lead < 0x3131 || lead > 0x3163)
         return ch;
diff --git a/firmware/include/diacritic.h b/firmware/include/diacritic.h
index cfb6ac034c..e7a51eb095 100644
--- a/firmware/include/diacritic.h
+++ b/firmware/include/diacritic.h
@@ -27,7 +27,7 @@
  * Sets is_rtl (if it's not NULL) to whether the character
  * belongs to an RTL language.
 */
-bool is_diacritic(const unsigned short char_code, bool *is_rtl);
+bool is_diacritic(const ucschar_t char_code, bool *is_rtl);
 
 /* Note IS_DIACRITIC macros may elide the function call
  * therefore there is a separate _RTL version that requires a bool pointer
diff --git a/firmware/include/font_cache.h b/firmware/include/font_cache.h
index 1809720ed5..e9c2edbd1b 100644
--- a/firmware/include/font_cache.h
+++ b/firmware/include/font_cache.h
@@ -21,24 +21,25 @@
 #ifndef _FONT_CACHE_H_
 #define _FONT_CACHE_H_
 #include <stdbool.h>
+#include "config.h"
 #include "lru.h"
 
 /*******************************************************************************
- * 
+ *
  ******************************************************************************/
 struct font_cache
 {
     struct lru _lru;
-    int _size;
-    int _capacity;
-    int _prev_char_code;
+    unsigned int _size;
+    unsigned int _capacity;
+    ucschar_t _prev_char_code;
     int _prev_result;
     short *_index; /* index of lru handles in char_code order */
 };
 
 struct font_cache_entry
 {
-    unsigned short _char_code;
+    ucschar_t _char_code;
     unsigned char width;
     unsigned char bitmap[1]; /* place holder */
 };
@@ -55,7 +56,7 @@ void font_cache_create(
  * Note: With cache_only this can return NULL, which otherwise never happens */
 struct font_cache_entry* font_cache_get(
     struct font_cache* fcache,
-    unsigned short char_code,
+    ucschar_t char_code,
     bool cache_only,
     void (*callback) (struct font_cache_entry* p, void *callback_data),
     void *callback_data);
diff --git a/firmware/include/lru.h b/firmware/include/lru.h
index cd271afbd8..5d33640983 100644
--- a/firmware/include/lru.h
+++ b/firmware/include/lru.h
@@ -33,6 +33,7 @@ struct lru
     void *_base;
 };
 
+/* LRU_SLOT_OVERHEAD is the fixed portion of struct lru_node */
 #define LRU_SLOT_OVERHEAD (2 * sizeof(short))
 
 /* Create LRU list with specified size from buf. */
@@ -45,4 +46,3 @@ void *lru_data(struct lru* pl, short handle);
 void lru_traverse(struct lru* pl, void (*callback)(void* data));
 
 #endif /* LRU_H */
-
diff --git a/firmware/include/rbunicode.h b/firmware/include/rbunicode.h
index e4cd6be2fe..48ca1b2583 100644
--- a/firmware/include/rbunicode.h
+++ b/firmware/include/rbunicode.h
@@ -27,7 +27,7 @@
  */
 #ifndef _RBUNICODE_H_
 #define _RBUNICODE_H_
- 
+
 #include "config.h"
 #include <stdbool.h>
 
@@ -63,8 +63,9 @@ unsigned char* utf16LEdecode(const unsigned char *utf16, unsigned char *utf8, in
 unsigned char* utf16BEdecode(const unsigned char *utf16, unsigned char *utf8, int count);
 unsigned char* utf16decode(const unsigned char *utf16, unsigned char *utf8, int count, int utf8_size, bool le);
 bool utf16_has_bom(const unsigned char *utf16, bool *le);
+unsigned long utf16len_utf8(const unsigned char *utf8);
 unsigned long utf8length(const unsigned char *utf8);
-const unsigned char* utf8decode(const unsigned char *utf8, unsigned short *ucs);
+const unsigned char* utf8decode(const unsigned char *utf8, ucschar_t *ucs);
 void set_codepage(int cp);
 int get_codepage(void);
 int utf8seek(const unsigned char* utf8, int offset);
diff --git a/firmware/target/hosted/filesystem-win32.c b/firmware/target/hosted/filesystem-win32.c
index ebb7f283ac..ce4500f46d 100644
--- a/firmware/target/hosted/filesystem-win32.c
+++ b/firmware/target/hosted/filesystem-win32.c
@@ -63,55 +63,78 @@ static void win32_last_error_errno(void)
 static HANDLE win32_open(const char *ospath);
 static int win32_stat(const char *ospath, LPBY_HANDLE_FILE_INFORMATION lpInfo);
 
-unsigned short * strcpy_utf8ucs2(unsigned short *buffer,
-                                 const unsigned char *utf8)
+static unsigned short * strcpy_utf8utf16(unsigned short *buffer,
+                                         const unsigned char *utf8)
 {
-    for (wchar_t *ucs2 = buffer;
-         ((utf8 = utf8decode(utf8, ucs2)), *ucs2); ucs2++);
+    for (wchar_t *ucs = buffer; *ucs ; ucs++) {
+        ucschar_t cp;
+        utf8 = utf8decode(utf8, &cp);
+#ifdef UNICODE32
+        if (cp > 0x10000) {
+            cp -= 0x10000;
+            *ucs++ = 0xd800 | (cp >> 10);
+            cp = 0xdc00 | (cp & 0x3ff);
+        }
+#endif
+        *ucs = cp;
+    }
     return buffer;
 }
 
-#if 0
-unsigned char * strcpy_ucs2utf8(unsigned char *buffer,
-                                const unsigned short *ucs2)
+#if 0 /* Unused in current code */
+static unsigned char * strcpy_utf16utf8(unsigned char *buffer,
+                                        const unsigned short *utf16buf)
 {
-    for (unsigned char *utf8 = buffer;
-         ((utf8 = utf8encode(*ucs2, utf8)), *ucs2); ucs2++);
+    unsigned char *utf8 = buffer;
+
+    /* windows is always LE */
+    const int le = 1;
+
+    while (*utf16buf) {
+        const unsigned char *utf16 = (const unsigned char *)utf16buf;
+        unsigned long ucs;
+        /* Check for a surrogate pair */
+        if (*(utf16 + le) >= 0xD8 && *(utf16 + le) < 0xE0) {
+            ucs = 0x10000 + ((utf16[1 - le] << 10) | ((utf16[le] - 0xD8) << 18)
+                  | utf16[2 + (1 - le)] | ((utf16[2 + le] - 0xDC) << 8));
+            utf16buf += 2;
+        } else {
+            ucs = utf16[le] << 8 | utf16[1 - le];
+            utf16buf++;
+        }
+        utf8 = utf8encode(ucs, utf8);
+    }
     return buffer;
 }
-
-size_t strlen_utf8ucs2(const unsigned char *utf8)
-{
-    /* This won't properly count multiword ucs2 so use the alternative
-       below for now which doesn't either */
-    size_t length = 0;
-    unsigned short ucschar[2];
-    for (unsigned char c = *utf8; c;
-         ((utf8 = utf8decode(utf8, ucschar)), c = *utf8))
-        length++;
-
-    return length;
-}
-#endif /* 0 */
-
-size_t strlen_utf8ucs2(const unsigned char *utf8)
-{
-    return utf8length(utf8);
-}
-
-size_t strlen_ucs2utf8(const unsigned short *ucs2)
+static size_t strlen_utf16utf8(const unsigned short *utf16buf)
 {
     size_t length = 0;
     unsigned char utf8char[4];
 
-    for (unsigned short c = *ucs2; c; (c = *++ucs2))
-        length += utf8encode(c, utf8char) - utf8char;
+    /* windows is always LE */
+    const int le = 1;
 
+    while (*utf16buf) {
+        const unsigned char *utf16 = (const unsigned char *)utf16buf;
+        unsigned long ucs;
+        /* Check for a surrogate pair */
+        if (*(utf16 + le) >= 0xD8 && *(utf16 + le) < 0xE0) {
+            ucs = 0x10000 + ((utf16[1 - le] << 10) | ((utf16[le] - 0xD8) << 18)
+                  | utf16[2 + (1 - le)] | ((utf16[2 + le] - 0xDC) << 8));
+            utf16buf += 2;
+        } else {
+            ucs = utf16[le] << 8 | utf16[1 - le];
+            utf16buf++;
+        }
+        length += utf8encode(ucs, utf8char) - utf8char;
+    }
     return length;
 }
+#endif
 
-size_t strlcpy_ucs2utf8(char *buffer, const unsigned short *ucs2,
-                        size_t bufsize)
+/* Note: Must be exported */
+size_t strlcpy_utf16utf8(char *buffer, const unsigned short *utf16,
+                         size_t bufsize)
 {
     if (!buffer)
         bufsize = 0;
@@ -119,12 +142,24 @@ size_t strlcpy_ucs2utf8(char *buffer, const unsigned short *ucs2,
     size_t length = 0;
     unsigned char utf8char[4];
 
-    for (unsigned short c = *ucs2; c; (c = *++ucs2))
+    unsigned long ucc;
+    while(*utf16)
     {
+        /* Check for a surrogate UTF16 pair */
+        if (*utf16 >= 0xd800 && *utf16 < 0xdc00 &&
+            *(utf16+1) >= 0xdc00 && *(utf16+1) < 0xe000) {
+            ucc = 0x10000 + (((*utf16 & 0x3ff) << 10) | (*(utf16+1) & 0x3ff));
+            utf16++;
+        } else {
+            ucc = *utf16;
+        }
+
         /* If the last character won't fit, this won't split it */
-        size_t utf8size = utf8encode(c, utf8char) - utf8char;
+        size_t utf8size = utf8encode(ucc, utf8char) - utf8char;
         if ((length += utf8size) < bufsize)
             buffer = mempcpy(buffer, utf8char, utf8size);
+
+        utf16++;
     }
 
     /* Above won't ever copy to very end */
@@ -134,44 +169,44 @@ size_t strlcpy_ucs2utf8(char *buffer, const unsigned short *ucs2,
     return length;
 }
 
-#define _toucs2(utf8) \
+#define _toutf16(utf8) \
     ({ const char *_utf8 = (utf8);         \
-       size_t _l = strlen_utf8ucs2(_utf8); \
+       size_t _l = utf16len_utf8(_utf8); \
        void *_buffer = alloca((_l + 1)*2); \
-       strcpy_utf8ucs2(_buffer, _utf8); })
+       strcpy_utf8utf16(_buffer, _utf8); })
 
-#define _toutf8(ucs2) \
-    ({ const char *_ucs2 = (ucs2);         \
-       size_t _l = strlen_ucs2utf8(_ucs2); \
+#define _toutf8(utf16) \
+    ({ const char *_ucs = (utf16);         \
+       size_t _l = strlen_utf16utf8(_ucs); \
        void *_buffer = alloca(_l + 1);     \
-       strcpy_ucs2utf8(_buffer, _ucs2); })
+       strcpy_utf16utf8(_buffer, _ucs); })
 
 int os_open(const char *ospath, int oflag, ...)
 {
-    return _wopen(_toucs2(ospath), oflag __OPEN_MODE_ARG);
+    return _wopen(_toutf16(ospath), oflag __OPEN_MODE_ARG);
 }
 
 int os_creat(const char *ospath, mode_t mode)
 {
-    return _wcreat(_toucs2(ospath), mode);
+    return _wcreat(_toutf16(ospath), mode);
 }
 
 int os_stat(const char *ospath, struct _stat *s)
 {
-    return _wstat(_toucs2(ospath), s);
+    return _wstat(_toutf16(ospath), s);
 }
 
 int os_remove(const char *ospath)
 {
-    return _wremove(_toucs2(ospath));
+    return _wremove(_toutf16(ospath));
 }
 
 int os_rename(const char *osold, const char *osnew)
 {
     int errnum = errno;
 
-    const wchar_t *wchosold = _toucs2(osold);
-    const wchar_t *wchosnew = _toucs2(osnew);
+    const wchar_t *wchosold = _toutf16(osold);
+    const wchar_t *wchosnew = _toutf16(osnew);
 
     int rc = _wrename(wchosold, wchosnew);
     if (rc < 0 && errno == EEXIST)
@@ -213,18 +248,18 @@ bool os_file_exists(const char *ospath)
 
 _WDIR * os_opendir(const char *osdirname)
 {
-    return _wopendir(_toucs2(osdirname));
+    return _wopendir(_toutf16(osdirname));
 }
 
 int os_mkdir(const char *ospath, mode_t mode)
 {
-    return _wmkdir(_toucs2(ospath));
+    return _wmkdir(_toutf16(ospath));
     (void)mode;
 }
 
 int os_rmdir(const char *ospath)
 {
-    return _wrmdir(_toucs2(ospath));
+    return _wrmdir(_toutf16(ospath));
 }
 
 int os_dirfd(_WDIR *osdirp)
@@ -288,7 +323,7 @@ static HANDLE win32_open(const char *ospath)
 {
     /* FILE_FLAG_BACKUP_SEMANTICS is required for this to succeed at opening
        a directory */
-    HANDLE h = CreateFileW(_toucs2(ospath), GENERIC_READ,
+    HANDLE h = CreateFileW(_toutf16(ospath), GENERIC_READ,
                            FILE_SHARE_READ | FILE_SHARE_WRITE |
                            FILE_SHARE_DELETE, NULL, OPEN_EXISTING,
                            FILE_FLAG_BACKUP_SEMANTICS, NULL);
@@ -479,7 +514,7 @@ void volume_size(IF_MV(int volume,) sector_t *sizep, sector_t *freep)
 
     char volpath[MAX_PATH];
     if (os_volume_path(IF_MV(volume, ) volpath, sizeof (volpath)) >= 0)
-        GetDiskFreeSpaceExW(_toucs2(volpath), &free, &size, NULL);
+        GetDiskFreeSpaceExW(_toutf16(volpath), &free, &size, NULL);
 
     if (sizep)
         *sizep = size.QuadPart / 1024;
diff --git a/firmware/target/hosted/filesystem-win32.h b/firmware/target/hosted/filesystem-win32.h
index 1d8f2749f9..c6e89a66aa 100644
--- a/firmware/target/hosted/filesystem-win32.h
+++ b/firmware/target/hosted/filesystem-win32.h
@@ -27,10 +27,10 @@
 /* filesystem-win32.c contains some string functions that could be useful
  * elsewhere; just move them away to unicode.c or something if they prove
  * so. */
-size_t strlcpy_ucs2utf8(char *buffer, const unsigned short *ucs,
-                        size_t bufsize);
+size_t strlcpy_utf16utf8(char *buffer, const unsigned short *utf16,
+                         size_t bufsize);
 
-#define strlcpy_from_os strlcpy_ucs2utf8
+#define strlcpy_from_os strlcpy_utf16utf8
 #endif /* __MINGW32__ */
 
 #endif /* !OSFUNCTIONS_DECLARED */
diff --git a/lib/rbcodec/metadata/id3tags.c b/lib/rbcodec/metadata/id3tags.c
index bbcf728dc7..8016574ff1 100644
--- a/lib/rbcodec/metadata/id3tags.c
+++ b/lib/rbcodec/metadata/id3tags.c
@@ -1092,9 +1092,9 @@ retry_with_limit:
 
                     if (!parse_as_utf8(tag, &bytesread))
                     {
-                        /* UTF-8 could potentially be 3 times larger */
+                        /* UTF-8 could potentially be 4 times larger */
                         /* so we need to create a new buffer         */
-                        int utf8_size = (3 * bytesread);
+                        int utf8_size = (4 * bytesread);
                         if (utf8_size > ID3V2_BUF_SIZE)
                         {
                             //limit stack allocation to avoid stack overflow
diff --git a/tools/convbdf.c b/tools/convbdf.c
index 5534de1cbb..d452a3357c 100644
--- a/tools/convbdf.c
+++ b/tools/convbdf.c
@@ -116,7 +116,7 @@ int gen_h = 0;
 int gen_fnt = 0;
 int gen_map = 1;
 int start_char = 0;
-int limit_char = 65535;
+int limit_char = 0x10FFFF;
 int oflag = 0;
 char outfile[256];
 
@@ -569,7 +569,7 @@ struct font* bdf_read_font(char *path)
 int bdf_read_header(FILE *fp, struct font* pf)
 {
     int encoding;
-    int firstchar = 65535;
+    int firstchar = 0x10FFFF;
     int lastchar = -1;
     char buf[256];
     char facename[256];
diff --git a/tools/convttf.c b/tools/convttf.c
index 3df08b664f..845ea9c90a 100644
--- a/tools/convttf.c
+++ b/tools/convttf.c
@@ -91,7 +91,7 @@ static int eid = DEFAULT_ENCODING_ID;
 static FT_UShort nocmap;
 
 int pct                     = 0; /* display ttc table if it is not zero. */
-FT_Long         max_char    = 65535;
+FT_Long         max_char    = 0x10FFFF;
 int             pixel_size  = 15;
 FT_Long         start_char  = 0;
 FT_Long         limit_char;