[locale.stdcvt]

llvm-svn: 105174

1 files changed, 2037 insertions, 252 deletions

diff --git a/libcxx/src/locale.cpp b/libcxx/src/locale.cpp
index a65d6ed3d71..6c41abfb70e 100644
--- a/libcxx/src/locale.cpp
+++ b/libcxx/src/locale.cpp
@@ -9,6 +9,7 @@
 
 #include "string"
 #include "locale"
+#include "codecvt"
 #include "vector"
 #include "algorithm"
 #include "algorithm"
@@ -1304,163 +1305,268 @@ codecvt<wchar_t, char, mbstate_t>::do_max_length() const throw()
 // 040000 - 0FFFFF  D8C0 - DBBF, DC00 - DFFF  F1 - F3, 80 - BF, 80 - BF, 80 - BF   786432
 // 100000 - 10FFFF  DBC0 - DBFF, DC00 - DFFF  F4 - F4, 80 - 8F, 80 - BF, 80 - BF    65536
 
-// template <> class codecvt<char16_t, char, mbstate_t>
-
-locale::id codecvt<char16_t, char, mbstate_t>::id; 
-
-codecvt<char16_t, char, mbstate_t>::~codecvt()
+static
+codecvt_base::result
+utf16_to_utf8(const uint16_t* frm, const uint16_t* frm_end, const uint16_t*& frm_nxt,
+              uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+              unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
+    {
+        if (to_end-to_nxt < 3)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xEF);
+        *to_nxt++ = static_cast<uint8_t>(0xBB);
+        *to_nxt++ = static_cast<uint8_t>(0xBF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint16_t wc1 = *frm_nxt;
+        if (wc1 > Maxcode)
+            return codecvt_base::error;
+        if (wc1 < 0x0080)
+        {
+            if (to_end-to_nxt < 1)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc1);
+        }
+        else if (wc1 < 0x0800)
+        {
+            if (to_end-to_nxt < 2)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xC0 | (wc1 >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | (wc1 & 0x03F));
+        }
+        else if (wc1 < 0xD800)
+        {
+            if (to_end-to_nxt < 3)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc1 >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc1 & 0x003F));
+        }
+        else if (wc1 < 0xDC00)
+        {
+            if (frm_end-frm_nxt < 2)
+                return codecvt_base::partial;
+            uint16_t wc2 = frm_nxt[1];
+            if ((wc2 & 0xFC00) != 0xDC00)
+                return codecvt_base::error;
+            if (to_end-to_nxt < 4)
+                return codecvt_base::partial;
+            if ((((((unsigned long)wc1 & 0x03C0) >> 6) + 1) << 16) +
+                (((unsigned long)wc1 & 0x003F) << 10) + (wc2 & 0x03FF) > Maxcode)
+                return codecvt_base::error;
+            ++frm_nxt;
+            uint8_t z = ((wc1 & 0x03C0) >> 6) + 1;
+            *to_nxt++ = static_cast<uint8_t>(0xF0 | (z >> 2));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((z & 0x03) << 4)     | ((wc1 & 0x003C) >> 2));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0003) << 4) | ((wc2 & 0x03C0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc2 & 0x003F));
+        }
+        else if (wc1 < 0xE000)
+        {
+            return codecvt_base::error;
+        }
+        else
+        {
+            if (to_end-to_nxt < 3)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc1 >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc1 & 0x003F));
+        }
+    }
+    return codecvt_base::ok;
 }
 
-codecvt<char16_t, char, mbstate_t>::result
-codecvt<char16_t, char, mbstate_t>::do_out(state_type&,
-    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt, 
-    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+static
+codecvt_base::result
+utf16_to_utf8(const uint32_t* frm, const uint32_t* frm_end, const uint32_t*& frm_nxt,
+              uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+              unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end; ++frm_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
     {
-        intern_type wc1 = *frm_nxt;
+        if (to_end-to_nxt < 3)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xEF);
+        *to_nxt++ = static_cast<uint8_t>(0xBB);
+        *to_nxt++ = static_cast<uint8_t>(0xBF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint16_t wc1 = static_cast<uint16_t>(*frm_nxt);
+        if (wc1 > Maxcode)
+            return codecvt_base::error;
         if (wc1 < 0x0080)
         {
             if (to_end-to_nxt < 1)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(wc1);
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc1);
         }
         else if (wc1 < 0x0800)
         {
             if (to_end-to_nxt < 2)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xC0 | (wc1 >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 | (wc1 & 0x03F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xC0 | (wc1 >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | (wc1 & 0x03F));
         }
         else if (wc1 < 0xD800)
         {
             if (to_end-to_nxt < 3)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xE0 |  (wc1 >> 12));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc1 & 0x0FC0) >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 |  (wc1 & 0x003F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc1 >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc1 & 0x003F));
         }
         else if (wc1 < 0xDC00)
         {
             if (frm_end-frm_nxt < 2)
-                return partial;
-            intern_type wc2 = frm_nxt[1];
+                return codecvt_base::partial;
+            uint16_t wc2 = static_cast<uint16_t>(frm_nxt[1]);
             if ((wc2 & 0xFC00) != 0xDC00)
-                return error;
+                return codecvt_base::error;
             if (to_end-to_nxt < 4)
-                return partial;
+                return codecvt_base::partial;
+            if ((((((unsigned long)wc1 & 0x03C0) >> 6) + 1) << 16) +
+                (((unsigned long)wc1 & 0x003F) << 10) + (wc2 & 0x03FF) > Maxcode)
+                return codecvt_base::error;
             ++frm_nxt;
-            unsigned char z = ((wc1 & 0x03C0) >> 6) + 1;
-            *to_nxt++ = static_cast<extern_type>(0xF0 | (z >> 2));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((z & 0x03) << 4)     | ((wc1 & 0x003C) >> 2));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc1 & 0x0003) << 4) | ((wc2 & 0x03C0) >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 |  (wc2 & 0x003F));
+            uint8_t z = ((wc1 & 0x03C0) >> 6) + 1;
+            *to_nxt++ = static_cast<uint8_t>(0xF0 | (z >> 2));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((z & 0x03) << 4)     | ((wc1 & 0x003C) >> 2));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0003) << 4) | ((wc2 & 0x03C0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc2 & 0x003F));
         }
         else if (wc1 < 0xE000)
         {
-            return error;
+            return codecvt_base::error;
         }
         else
         {
             if (to_end-to_nxt < 3)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xE0 |  (wc1 >> 12));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc1 & 0x0FC0) >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 |  (wc1 & 0x003F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc1 >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc1 & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc1 & 0x003F));
         }
     }
-    return ok;
+    return codecvt_base::ok;
 }
 
-codecvt<char16_t, char, mbstate_t>::result
-codecvt<char16_t, char, mbstate_t>::do_in(state_type&,
-    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt, 
-    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+static
+codecvt_base::result
+utf8_to_utf16(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+              uint16_t* to, uint16_t* to_end, uint16_t*& to_nxt,
+              unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
     {
-        unsigned char c1 = static_cast<unsigned char>(*frm_nxt);
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
+    for (; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    {
+        uint8_t c1 = *frm_nxt;
+        if (c1 > Maxcode)
+            return codecvt_base::error;
         if (c1 < 0x80)
         {
-            *to_nxt = static_cast<intern_type>(c1);
+            *to_nxt = static_cast<uint16_t>(c1);
             ++frm_nxt;
         }
         else if (c1 < 0xC2)
         {
-            return error;
+            return codecvt_base::error;
         }
         else if (c1 < 0xE0)
         {
             if (frm_end-frm_nxt < 2)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
             if ((c2 & 0xC0) != 0x80)
-                return error;
-            *to_nxt = static_cast<intern_type>(((c1 & 0x1F) << 6)
-                                              | (c2 & 0x3F));
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x1F) << 6) | (c2 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
             frm_nxt += 2;
         }
         else if (c1 < 0xF0)
         {
             if (frm_end-frm_nxt < 3)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
             switch (c1)
             {
             case 0xE0:
                 if ((c2 & 0xE0) != 0xA0)
-                    return error;
+                    return codecvt_base::error;
                  break;
             case 0xED:
                 if ((c2 & 0xE0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             default:
                 if ((c2 & 0xC0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             }
             if ((c3 & 0xC0) != 0x80)
-                return error;
-            *to_nxt = static_cast<intern_type>(((c1 & 0x0F) << 12)
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x0F) << 12)
                                              | ((c2 & 0x3F) << 6)
                                              |  (c3 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
             frm_nxt += 3;
         }
         else if (c1 < 0xF5)
         {
             if (frm_end-frm_nxt < 4)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
-            unsigned char c4 = frm_nxt[3];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint8_t c4 = frm_nxt[3];
             switch (c1)
             {
             case 0xF0:
                 if (!(0x90 <= c2 && c2 <= 0xBF))
-                    return error;
+                    return codecvt_base::error;
                  break;
             case 0xF4:
                 if ((c2 & 0xF0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             default:
                 if ((c2 & 0xC0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             }
             if ((c3 & 0xC0) != 0x80 || (c4 & 0xC0) != 0x80)
-                return error;
+                return codecvt_base::error;
             if (to_end-to_nxt < 2)
-                return partial;
-            *to_nxt = static_cast<intern_type>(
+                return codecvt_base::partial;
+            if (((((unsigned long)c1 & 7) << 18) +
+                (((unsigned long)c2 & 0x3F) << 12) +
+                (((unsigned long)c3 & 0x3F) << 6) + (c4 & 0x3F)) > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint16_t>(
                     0xD800
                   | (((((c1 & 0x07) << 2) | ((c2 & 0x30) >> 4)) - 1) << 6)
                   | ((c2 & 0x0F) << 2)
                   | ((c3 & 0x30) >> 4));
-            *++to_nxt = static_cast<intern_type>(
+            *++to_nxt = static_cast<uint16_t>(
                     0xDC00
                   | ((c3 & 0x0F) << 6)
                   |  (c4 & 0x3F));
@@ -1468,40 +1574,151 @@ codecvt<char16_t, char, mbstate_t>::do_in(state_type&,
         }
         else
         {
-            return error;
+            return codecvt_base::error;
         }
     }
-    return frm_nxt < frm_end ? partial : ok;
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
 }
 
-codecvt<char16_t, char, mbstate_t>::result
-codecvt<char16_t, char, mbstate_t>::do_unshift(state_type&,
-    extern_type* to, extern_type*, extern_type*& to_nxt) const
+static
+codecvt_base::result
+utf8_to_utf16(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+              uint32_t* to, uint32_t* to_end, uint32_t*& to_nxt,
+              unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
+    frm_nxt = frm;
     to_nxt = to;
-    return noconv;
-}
-
-int
-codecvt<char16_t, char, mbstate_t>::do_encoding() const throw()
-{
-    return 0;
-}
-
-bool
-codecvt<char16_t, char, mbstate_t>::do_always_noconv() const throw()
-{
-    return false;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
+    for (; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    {
+        uint8_t c1 = *frm_nxt;
+        if (c1 > Maxcode)
+            return codecvt_base::error;
+        if (c1 < 0x80)
+        {
+            *to_nxt = static_cast<uint32_t>(c1);
+            ++frm_nxt;
+        }
+        else if (c1 < 0xC2)
+        {
+            return codecvt_base::error;
+        }
+        else if (c1 < 0xE0)
+        {
+            if (frm_end-frm_nxt < 2)
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            if ((c2 & 0xC0) != 0x80)
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x1F) << 6) | (c2 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(t);
+            frm_nxt += 2;
+        }
+        else if (c1 < 0xF0)
+        {
+            if (frm_end-frm_nxt < 3)
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            switch (c1)
+            {
+            case 0xE0:
+                if ((c2 & 0xE0) != 0xA0)
+                    return codecvt_base::error;
+                 break;
+            case 0xED:
+                if ((c2 & 0xE0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            default:
+                if ((c2 & 0xC0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            }
+            if ((c3 & 0xC0) != 0x80)
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x0F) << 12)
+                                             | ((c2 & 0x3F) << 6)
+                                             |  (c3 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(t);
+            frm_nxt += 3;
+        }
+        else if (c1 < 0xF5)
+        {
+            if (frm_end-frm_nxt < 4)
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint8_t c4 = frm_nxt[3];
+            switch (c1)
+            {
+            case 0xF0:
+                if (!(0x90 <= c2 && c2 <= 0xBF))
+                    return codecvt_base::error;
+                 break;
+            case 0xF4:
+                if ((c2 & 0xF0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            default:
+                if ((c2 & 0xC0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            }
+            if ((c3 & 0xC0) != 0x80 || (c4 & 0xC0) != 0x80)
+                return codecvt_base::error;
+            if (to_end-to_nxt < 2)
+                return codecvt_base::partial;
+            if (((((unsigned long)c1 & 7) << 18) +
+                (((unsigned long)c2 & 0x3F) << 12) +
+                (((unsigned long)c3 & 0x3F) << 6) + (c4 & 0x3F)) > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(
+                    0xD800
+                  | (((((c1 & 0x07) << 2) | ((c2 & 0x30) >> 4)) - 1) << 6)
+                  | ((c2 & 0x0F) << 2)
+                  | ((c3 & 0x30) >> 4));
+            *++to_nxt = static_cast<uint32_t>(
+                    0xDC00
+                  | ((c3 & 0x0F) << 6)
+                  |  (c4 & 0x3F));
+            frm_nxt += 4;
+        }
+        else
+        {
+            return codecvt_base::error;
+        }
+    }
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
 }
 
+static
 int
-codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
-    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+utf8_to_utf16_length(const uint8_t* frm, const uint8_t* frm_end,
+                     size_t mx, unsigned long Maxcode = 0x10FFFF,
+                     codecvt_mode mode = codecvt_mode(0))
 {
-    const extern_type* frm_nxt = frm;
+    const uint8_t* frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
     for (size_t nchar16_t = 0; frm_nxt < frm_end && nchar16_t < mx; ++nchar16_t)
     {
-        unsigned char c1 = static_cast<unsigned char>(*frm_nxt);
+        uint8_t c1 = *frm_nxt;
+        if (c1 > Maxcode)
+            break;
         if (c1 < 0x80)
         {
             ++frm_nxt;
@@ -1514,14 +1731,20 @@ codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
         {
             if ((frm_end-frm_nxt < 2) || (frm_nxt[1] & 0xC0) != 0x80)
                 break;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x1F) << 6) | (frm_nxt[1] & 0x3F));
+            if (t > Maxcode)
+                break;
             frm_nxt += 2;
         }
         else if (c1 < 0xF0)
         {
             if (frm_end-frm_nxt < 3)
                 break;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x0F) << 12)
+                                             | ((c2 & 0x3F) << 6)
+                                             |  (c3 & 0x3F));
             switch (c1)
             {
             case 0xE0:
@@ -1539,15 +1762,17 @@ codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
             }
             if ((c3 & 0xC0) != 0x80)
                 break;
+            if ((((c1 & 0x0F) << 12) | ((c2 & 0x3F) << 6) | (c3 & 0x3F)) > Maxcode)
+                break;
             frm_nxt += 3;
         }
         else if (c1 < 0xF5)
         {
             if (frm_end-frm_nxt < 4 || mx-nchar16_t < 2)
                 break;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
-            unsigned char c4 = frm_nxt[3];
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint8_t c4 = frm_nxt[3];
             switch (c1)
             {
             case 0xF0:
@@ -1565,6 +1790,10 @@ codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
             }
             if ((c3 & 0xC0) != 0x80 || (c4 & 0xC0) != 0x80)
                 break;
+            if (((((unsigned long)c1 & 7) << 18) +
+                (((unsigned long)c2 & 0x3F) << 12) +
+                (((unsigned long)c3 & 0x3F) << 6) + (c4 & 0x3F)) > Maxcode)
+                break;
             ++nchar16_t;
             frm_nxt += 4;
         }
@@ -1576,188 +1805,195 @@ codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
     return static_cast<int>(frm_nxt - frm);
 }
 
-int
-codecvt<char16_t, char, mbstate_t>::do_max_length() const throw()
-{
-    return 4;
-}
-
-// template <> class codecvt<char32_t, char, mbstate_t>
-
-locale::id codecvt<char32_t, char, mbstate_t>::id; 
-
-codecvt<char32_t, char, mbstate_t>::~codecvt()
-{
-}
-
-codecvt<char32_t, char, mbstate_t>::result
-codecvt<char32_t, char, mbstate_t>::do_out(state_type&,
-    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt, 
-    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+static
+codecvt_base::result
+ucs4_to_utf8(const uint32_t* frm, const uint32_t* frm_end, const uint32_t*& frm_nxt,
+             uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+             unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end; ++frm_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
     {
-        intern_type wc = *frm_nxt;
-        if ((wc & 0xFFFFF800) == 0x00D800 || wc >= 0x110000)
-            return error;
+        if (to_end-to_nxt < 3)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xEF);
+        *to_nxt++ = static_cast<uint8_t>(0xBB);
+        *to_nxt++ = static_cast<uint8_t>(0xBF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint32_t wc = *frm_nxt;
+        if ((wc & 0xFFFFF800) == 0x00D800 || wc > Maxcode)
+            return codecvt_base::error;
         if (wc < 0x000080)
         {
             if (to_end-to_nxt < 1)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(wc);
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc);
         }
         else if (wc < 0x000800)
         {
             if (to_end-to_nxt < 2)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xC0 | (wc >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 | (wc & 0x03F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xC0 | (wc >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | (wc & 0x03F));
         }
         else if (wc < 0x010000)
         {
             if (to_end-to_nxt < 3)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xE0 |  (wc >> 12));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc & 0x0FC0) >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 |  (wc & 0x003F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc & 0x003F));
         }
         else // if (wc < 0x110000)
         {
             if (to_end-to_nxt < 4)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(0xF0 |  (wc >> 18));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc & 0x03F000) >> 12));
-            *to_nxt++ = static_cast<extern_type>(0x80 | ((wc & 0x000FC0) >> 6));
-            *to_nxt++ = static_cast<extern_type>(0x80 |  (wc & 0x00003F));
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xF0 |  (wc >> 18));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc & 0x03F000) >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc & 0x000FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc & 0x00003F));
         }
     }
-    return ok;
+    return codecvt_base::ok;
 }
 
-codecvt<char32_t, char, mbstate_t>::result
-codecvt<char32_t, char, mbstate_t>::do_in(state_type&,
-    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt, 
-    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+static
+codecvt_base::result
+utf8_to_ucs4(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+             uint32_t* to, uint32_t* to_end, uint32_t*& to_nxt,
+             unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
+    for (; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
     {
-        unsigned char c1 = static_cast<unsigned char>(*frm_nxt);
+        uint8_t c1 = static_cast<uint8_t>(*frm_nxt);
         if (c1 < 0x80)
         {
-            *to_nxt = static_cast<intern_type>(c1);
+            if (c1 > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(c1);
             ++frm_nxt;
         }
         else if (c1 < 0xC2)
         {
-            return error;
+            return codecvt_base::error;
         }
         else if (c1 < 0xE0)
         {
             if (frm_end-frm_nxt < 2)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
             if ((c2 & 0xC0) != 0x80)
-                return error;
-            *to_nxt = static_cast<intern_type>(((c1 & 0x1F) << 6)
+                return codecvt_base::error;
+            uint32_t t = static_cast<uint32_t>(((c1 & 0x1F) << 6)
                                               | (c2 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
             frm_nxt += 2;
         }
         else if (c1 < 0xF0)
         {
             if (frm_end-frm_nxt < 3)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
             switch (c1)
             {
             case 0xE0:
                 if ((c2 & 0xE0) != 0xA0)
-                    return error;
+                    return codecvt_base::error;
                  break;
             case 0xED:
                 if ((c2 & 0xE0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             default:
                 if ((c2 & 0xC0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             }
             if ((c3 & 0xC0) != 0x80)
-                return error;
-            *to_nxt = static_cast<intern_type>(((c1 & 0x0F) << 12)
+                return codecvt_base::error;
+            uint32_t t = static_cast<uint32_t>(((c1 & 0x0F) << 12)
                                              | ((c2 & 0x3F) << 6)
                                              |  (c3 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
             frm_nxt += 3;
         }
         else if (c1 < 0xF5)
         {
             if (frm_end-frm_nxt < 4)
-                return partial;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
-            unsigned char c4 = frm_nxt[3];
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint8_t c4 = frm_nxt[3];
             switch (c1)
             {
             case 0xF0:
                 if (!(0x90 <= c2 && c2 <= 0xBF))
-                    return error;
+                    return codecvt_base::error;
                  break;
             case 0xF4:
                 if ((c2 & 0xF0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             default:
                 if ((c2 & 0xC0) != 0x80)
-                    return error;
+                    return codecvt_base::error;
                  break;
             }
             if ((c3 & 0xC0) != 0x80 || (c4 & 0xC0) != 0x80)
-                return error;
-            *to_nxt = static_cast<intern_type>(((c1 & 0x07) << 18)
+                return codecvt_base::error;
+            uint32_t t = static_cast<uint32_t>(((c1 & 0x07) << 18)
                                              | ((c2 & 0x3F) << 12)
                                              | ((c3 & 0x3F) << 6)
                                              |  (c4 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
             frm_nxt += 4;
         }
         else
         {
-            return error;
+            return codecvt_base::error;
         }
     }
-    return frm_nxt < frm_end ? partial : ok;
-}
-
-codecvt<char32_t, char, mbstate_t>::result
-codecvt<char32_t, char, mbstate_t>::do_unshift(state_type&,
-    extern_type* to, extern_type*, extern_type*& to_nxt) const
-{
-    to_nxt = to;
-    return noconv;
-}
-
-int
-codecvt<char32_t, char, mbstate_t>::do_encoding() const throw()
-{
-    return 0;
-}
-
-bool
-codecvt<char32_t, char, mbstate_t>::do_always_noconv() const throw()
-{
-    return false;
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
 }
 
+static
 int
-codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
-    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+utf8_to_ucs4_length(const uint8_t* frm, const uint8_t* frm_end,
+                    size_t mx, unsigned long Maxcode = 0x10FFFF,
+                    codecvt_mode mode = codecvt_mode(0))
 {
-    const extern_type* frm_nxt = frm;
+    const uint8_t* frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
     for (size_t nchar32_t = 0; frm_nxt < frm_end && nchar32_t < mx; ++nchar32_t)
     {
-        unsigned char c1 = static_cast<unsigned char>(*frm_nxt);
+        uint8_t c1 = static_cast<uint8_t>(*frm_nxt);
         if (c1 < 0x80)
         {
+            if (c1 > Maxcode)
+                break;
             ++frm_nxt;
         }
         else if (c1 < 0xC2)
@@ -1768,14 +2004,16 @@ codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
         {
             if ((frm_end-frm_nxt < 2) || ((frm_nxt[1] & 0xC0) != 0x80))
                 break;
+            if ((((c1 & 0x1F) << 6) | (frm_nxt[1] & 0x3F)) > Maxcode)
+                break;
             frm_nxt += 2;
         }
         else if (c1 < 0xF0)
         {
             if (frm_end-frm_nxt < 3)
                 break;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
             switch (c1)
             {
             case 0xE0:
@@ -1793,15 +2031,17 @@ codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
             }
             if ((c3 & 0xC0) != 0x80)
                 break;
+            if ((((c1 & 0x0F) << 12) | ((c2 & 0x3F) << 6) | (c3 & 0x3F)) > Maxcode)
+                break;
             frm_nxt += 3;
         }
         else if (c1 < 0xF5)
         {
             if (frm_end-frm_nxt < 4)
                 break;
-            unsigned char c2 = frm_nxt[1];
-            unsigned char c3 = frm_nxt[2];
-            unsigned char c4 = frm_nxt[3];
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            uint8_t c4 = frm_nxt[3];
             switch (c1)
             {
             case 0xF0:
@@ -1819,6 +2059,13 @@ codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
             }
             if ((c3 & 0xC0) != 0x80 || (c4 & 0xC0) != 0x80)
                 break;
+            uint32_t t = static_cast<uint32_t>(((c1 & 0x07) << 18)
+                                             | ((c2 & 0x3F) << 12)
+                                             | ((c3 & 0x3F) << 6)
+                                             |  (c4 & 0x3F));
+            if ((((c1 & 0x07) << 18) | ((c2 & 0x3F) << 12) |
+                 ((c3 & 0x3F) << 6)  |  (c4 & 0x3F)) > Maxcode)
+                break;
             frm_nxt += 4;
         }
         else
@@ -1829,134 +2076,1672 @@ codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
     return static_cast<int>(frm_nxt - frm);
 }
 
-int
-codecvt<char32_t, char, mbstate_t>::do_max_length() const throw()
+static
+codecvt_base::result
+ucs2_to_utf8(const uint16_t* frm, const uint16_t* frm_end, const uint16_t*& frm_nxt,
+             uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+             unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    return 4;
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
+    {
+        if (to_end-to_nxt < 3)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xEF);
+        *to_nxt++ = static_cast<uint8_t>(0xBB);
+        *to_nxt++ = static_cast<uint8_t>(0xBF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint16_t wc = *frm_nxt;
+        if ((wc & 0xF800) == 0xD800 || wc > Maxcode)
+            return codecvt_base::error;
+        if (wc < 0x0080)
+        {
+            if (to_end-to_nxt < 1)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc);
+        }
+        else if (wc < 0x0800)
+        {
+            if (to_end-to_nxt < 2)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xC0 | (wc >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | (wc & 0x03F));
+        }
+        else // if (wc <= 0xFFFF)
+        {
+            if (to_end-to_nxt < 3)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xE0 |  (wc >> 12));
+            *to_nxt++ = static_cast<uint8_t>(0x80 | ((wc & 0x0FC0) >> 6));
+            *to_nxt++ = static_cast<uint8_t>(0x80 |  (wc & 0x003F));
+        }
+    }
+    return codecvt_base::ok;
 }
 
-// template <> class codecvt<char32_t, char16_t, mbstate_t>
-
-locale::id codecvt<char32_t, char16_t, mbstate_t>::id; 
+static
+codecvt_base::result
+utf8_to_ucs2(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+             uint16_t* to, uint16_t* to_end, uint16_t*& to_nxt,
+             unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
+{
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
+    for (; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    {
+        uint8_t c1 = static_cast<uint8_t>(*frm_nxt);
+        if (c1 < 0x80)
+        {
+            if (c1 > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint16_t>(c1);
+            ++frm_nxt;
+        }
+        else if (c1 < 0xC2)
+        {
+            return codecvt_base::error;
+        }
+        else if (c1 < 0xE0)
+        {
+            if (frm_end-frm_nxt < 2)
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            if ((c2 & 0xC0) != 0x80)
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x1F) << 6)
+                                              | (c2 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
+            frm_nxt += 2;
+        }
+        else if (c1 < 0xF0)
+        {
+            if (frm_end-frm_nxt < 3)
+                return codecvt_base::partial;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            switch (c1)
+            {
+            case 0xE0:
+                if ((c2 & 0xE0) != 0xA0)
+                    return codecvt_base::error;
+                 break;
+            case 0xED:
+                if ((c2 & 0xE0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            default:
+                if ((c2 & 0xC0) != 0x80)
+                    return codecvt_base::error;
+                 break;
+            }
+            if ((c3 & 0xC0) != 0x80)
+                return codecvt_base::error;
+            uint16_t t = static_cast<uint16_t>(((c1 & 0x0F) << 12)
+                                             | ((c2 & 0x3F) << 6)
+                                             |  (c3 & 0x3F));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
+            frm_nxt += 3;
+        }
+        else
+        {
+            return codecvt_base::error;
+        }
+    }
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
+}
 
-codecvt<char32_t, char16_t, mbstate_t>::~codecvt()
+static
+int
+utf8_to_ucs2_length(const uint8_t* frm, const uint8_t* frm_end,
+                    size_t mx, unsigned long Maxcode = 0x10FFFF,
+                    codecvt_mode mode = codecvt_mode(0))
 {
+    const uint8_t* frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 3 && frm_nxt[0] == 0xEF && frm_nxt[1] == 0xBB &&
+                                                          frm_nxt[2] == 0xBF)
+            frm_nxt += 3;
+    }
+    for (size_t nchar32_t = 0; frm_nxt < frm_end && nchar32_t < mx; ++nchar32_t)
+    {
+        uint8_t c1 = static_cast<uint8_t>(*frm_nxt);
+        if (c1 < 0x80)
+        {
+            if (c1 > Maxcode)
+                break;
+            ++frm_nxt;
+        }
+        else if (c1 < 0xC2)
+        {
+            break;
+        }
+        else if (c1 < 0xE0)
+        {
+            if ((frm_end-frm_nxt < 2) || ((frm_nxt[1] & 0xC0) != 0x80))
+                break;
+            if ((((c1 & 0x1F) << 6) | (frm_nxt[1] & 0x3F)) > Maxcode)
+                break;
+            frm_nxt += 2;
+        }
+        else if (c1 < 0xF0)
+        {
+            if (frm_end-frm_nxt < 3)
+                break;
+            uint8_t c2 = frm_nxt[1];
+            uint8_t c3 = frm_nxt[2];
+            switch (c1)
+            {
+            case 0xE0:
+                if ((c2 & 0xE0) != 0xA0)
+                    return static_cast<int>(frm_nxt - frm);
+                break;
+            case 0xED:
+                if ((c2 & 0xE0) != 0x80)
+                    return static_cast<int>(frm_nxt - frm);
+                 break;
+            default:
+                if ((c2 & 0xC0) != 0x80)
+                    return static_cast<int>(frm_nxt - frm);
+                 break;
+            }
+            if ((c3 & 0xC0) != 0x80)
+                break;
+            if ((((c1 & 0x0F) << 12) | ((c2 & 0x3F) << 6) | (c3 & 0x3F)) > Maxcode)
+                break;
+            frm_nxt += 3;
+        }
+        else
+        {
+            break;
+        }
+    }
+    return static_cast<int>(frm_nxt - frm);
 }
 
-codecvt<char32_t, char16_t, mbstate_t>::result
-codecvt<char32_t, char16_t, mbstate_t>::do_out(state_type&,
-    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt, 
-    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+static
+codecvt_base::result
+ucs4_to_utf16be(const uint32_t* frm, const uint32_t* frm_end, const uint32_t*& frm_nxt,
+                uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end; ++frm_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
     {
-        intern_type wc = *frm_nxt;
-        if ((wc & 0xFFFFF800) == 0x00D800 || wc >= 0x110000)
-            return error;
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xFE);
+        *to_nxt++ = static_cast<uint8_t>(0xFF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint32_t wc = *frm_nxt;
+        if ((wc & 0xFFFFF800) == 0x00D800 || wc > Maxcode)
+            return codecvt_base::error;
         if (wc < 0x010000)
         {
-            if (to_end-to_nxt < 1)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(wc);
+            if (to_end-to_nxt < 2)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc >> 8);
+            *to_nxt++ = static_cast<uint8_t>(wc);
         }
         else
         {
-            if (to_end-to_nxt < 2)
-                return partial;
-            *to_nxt++ = static_cast<extern_type>(
+            if (to_end-to_nxt < 4)
+                return codecvt_base::partial;
+            uint16_t t = static_cast<uint16_t>(
                     0xD800
                   | ((((wc & 0x1F0000) >> 16) - 1) << 6)
                   |   ((wc & 0x00FC00) >> 10));
-            *to_nxt++ = static_cast<extern_type>(
-                    0xDC00
-                  | (wc & 0x03FF));
+            *to_nxt++ = static_cast<uint8_t>(t >> 8);
+            *to_nxt++ = static_cast<uint8_t>(t);
+            t = static_cast<uint16_t>(0xDC00 | (wc & 0x03FF));
+            *to_nxt++ = static_cast<uint8_t>(t >> 8);
+            *to_nxt++ = static_cast<uint8_t>(t);
         }
     }
-    return ok;
+    return codecvt_base::ok;
 }
 
-codecvt<char32_t, char16_t, mbstate_t>::result
-codecvt<char32_t, char16_t, mbstate_t>::do_in(state_type&,
-    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt, 
-    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+static
+codecvt_base::result
+utf16be_to_ucs4(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+                uint32_t* to, uint32_t* to_end, uint32_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    for (frm_nxt = frm, to_nxt = to; frm_nxt < frm_end && to_nxt < to_end; ++to_nxt)
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
     {
-        extern_type c1 = *frm_nxt;
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFE && frm_nxt[1] == 0xFF)
+            frm_nxt += 2;
+    }
+    for (; frm_nxt < frm_end - 1 && to_nxt < to_end; ++to_nxt)
+    {
+        uint16_t c1 = frm_nxt[0] << 8 | frm_nxt[1];
         if ((c1 & 0xFC00) == 0xDC00)
-            return error;
+            return codecvt_base::error;
         if ((c1 & 0xFC00) != 0xD800)
         {
-            *to_nxt = static_cast<intern_type>(c1);
-            ++frm_nxt;
+            if (c1 > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(c1);
+            frm_nxt += 2;
         }
         else
         {
-            if (frm_end-frm_nxt < 2)
-                return partial;
-            extern_type c2 = frm_nxt[1];
+            if (frm_end-frm_nxt < 4)
+                return codecvt_base::partial;
+            uint16_t c2 = frm_nxt[2] << 8 | frm_nxt[3];
             if ((c2 & 0xFC00) != 0xDC00)
-                return error;
-            *to_nxt = static_cast<intern_type>(
+                return codecvt_base::error;
+            uint32_t t = static_cast<uint32_t>(
                     ((((c1 & 0x03C0) >> 6) + 1) << 16)
                   |   ((c1 & 0x003F) << 10)
                   |    (c2 & 0x03FF));
-            frm_nxt += 2;
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
+            frm_nxt += 4;
         }
     }
-    return frm_nxt < frm_end ? partial : ok;
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
 }
 
-codecvt<char32_t, char16_t, mbstate_t>::result
-codecvt<char32_t, char16_t, mbstate_t>::do_unshift(state_type&,
-    extern_type* to, extern_type*, extern_type*& to_nxt) const
+static
+int
+utf16be_to_ucs4_length(const uint8_t* frm, const uint8_t* frm_end,
+                       size_t mx, unsigned long Maxcode = 0x10FFFF,
+                       codecvt_mode mode = codecvt_mode(0))
 {
-    to_nxt = to;
-    return noconv;
+    const uint8_t* frm_nxt = frm;
+    frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFE && frm_nxt[1] == 0xFF)
+            frm_nxt += 2;
+    }
+    for (size_t nchar32_t = 0; frm_nxt < frm_end - 1 && nchar32_t < mx; ++nchar32_t)
+    {
+        uint16_t c1 = frm_nxt[0] << 8 | frm_nxt[1];
+        if ((c1 & 0xFC00) == 0xDC00)
+            break;
+        if ((c1 & 0xFC00) != 0xD800)
+        {
+            if (c1 > Maxcode)
+                break;
+            frm_nxt += 2;
+        }
+        else
+        {
+            if (frm_end-frm_nxt < 4)
+                break;
+            uint16_t c2 = frm_nxt[2] << 8 | frm_nxt[3];
+            if ((c2 & 0xFC00) != 0xDC00)
+                break;
+            uint32_t t = static_cast<uint32_t>(
+                    ((((c1 & 0x03C0) >> 6) + 1) << 16)
+                  |   ((c1 & 0x003F) << 10)
+                  |    (c2 & 0x03FF));
+            if (t > Maxcode)
+                break;
+            frm_nxt += 4;
+        }
+    }
+    return static_cast<int>(frm_nxt - frm);
 }
 
-int
-codecvt<char32_t, char16_t, mbstate_t>::do_encoding() const throw()
+static
+codecvt_base::result
+ucs4_to_utf16le(const uint32_t* frm, const uint32_t* frm_end, const uint32_t*& frm_nxt,
+                uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    return 0;
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
+    {
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(0xFF);
+            *to_nxt++ = static_cast<uint8_t>(0xFE);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint32_t wc = *frm_nxt;
+        if ((wc & 0xFFFFF800) == 0x00D800 || wc > Maxcode)
+            return codecvt_base::error;
+        if (wc < 0x010000)
+        {
+            if (to_end-to_nxt < 2)
+                return codecvt_base::partial;
+            *to_nxt++ = static_cast<uint8_t>(wc);
+            *to_nxt++ = static_cast<uint8_t>(wc >> 8);
+        }
+        else
+        {
+            if (to_end-to_nxt < 4)
+                return codecvt_base::partial;
+            uint16_t t = static_cast<uint16_t>(
+                    0xD800
+                  | ((((wc & 0x1F0000) >> 16) - 1) << 6)
+                  |   ((wc & 0x00FC00) >> 10));
+            *to_nxt++ = static_cast<uint8_t>(t);
+            *to_nxt++ = static_cast<uint8_t>(t >> 8);
+            t = static_cast<uint16_t>(0xDC00 | (wc & 0x03FF));
+            *to_nxt++ = static_cast<uint8_t>(t);
+            *to_nxt++ = static_cast<uint8_t>(t >> 8);
+        }
+    }
+    return codecvt_base::ok;
 }
 
-bool
-codecvt<char32_t, char16_t, mbstate_t>::do_always_noconv() const throw()
+static
+codecvt_base::result
+utf16le_to_ucs4(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+                uint32_t* to, uint32_t* to_end, uint32_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
 {
-    return false;
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFF && frm_nxt[1] == 0xFE)
+            frm_nxt += 2;
+    }
+    for (; frm_nxt < frm_end - 1 && to_nxt < to_end; ++to_nxt)
+    {
+        uint16_t c1 = frm_nxt[1] << 8 | frm_nxt[0];
+        if ((c1 & 0xFC00) == 0xDC00)
+            return codecvt_base::error;
+        if ((c1 & 0xFC00) != 0xD800)
+        {
+            if (c1 > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = static_cast<uint32_t>(c1);
+            frm_nxt += 2;
+        }
+        else
+        {
+            if (frm_end-frm_nxt < 4)
+                return codecvt_base::partial;
+            uint16_t c2 = frm_nxt[3] << 8 | frm_nxt[2];
+            if ((c2 & 0xFC00) != 0xDC00)
+                return codecvt_base::error;
+            uint32_t t = static_cast<uint32_t>(
+                    ((((c1 & 0x03C0) >> 6) + 1) << 16)
+                  |   ((c1 & 0x003F) << 10)
+                  |    (c2 & 0x03FF));
+            if (t > Maxcode)
+                return codecvt_base::error;
+            *to_nxt = t;
+            frm_nxt += 4;
+        }
+    }
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
 }
 
+static
 int
-codecvt<char32_t, char16_t, mbstate_t>::do_length(state_type&,
-    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+utf16le_to_ucs4_length(const uint8_t* frm, const uint8_t* frm_end,
+                       size_t mx, unsigned long Maxcode = 0x10FFFF,
+                       codecvt_mode mode = codecvt_mode(0))
 {
-    const extern_type* frm_nxt = frm;
-    for (size_t nchar32_t = 0; frm_nxt < frm_end && nchar32_t < mx; ++nchar32_t)
+    const uint8_t* frm_nxt = frm;
+    frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFF && frm_nxt[1] == 0xFE)
+            frm_nxt += 2;
+    }
+    for (size_t nchar32_t = 0; frm_nxt < frm_end - 1 && nchar32_t < mx; ++nchar32_t)
     {
-        extern_type c1 = *frm_nxt;
+        uint16_t c1 = frm_nxt[1] << 8 | frm_nxt[0];
         if ((c1 & 0xFC00) == 0xDC00)
             break;
         if ((c1 & 0xFC00) != 0xD800)
         {
-            ++frm_nxt;
+            if (c1 > Maxcode)
+                break;
+            frm_nxt += 2;
         }
         else
         {
-            if ((frm_end-frm_nxt < 2) || (frm_nxt[1] & 0xFC00) != 0xDC00)
+            if (frm_end-frm_nxt < 4)
                 break;
-            frm_nxt += 2;
+            uint16_t c2 = frm_nxt[3] << 8 | frm_nxt[2];
+            if ((c2 & 0xFC00) != 0xDC00)
+                break;
+            uint32_t t = static_cast<uint32_t>(
+                    ((((c1 & 0x03C0) >> 6) + 1) << 16)
+                  |   ((c1 & 0x003F) << 10)
+                  |    (c2 & 0x03FF));
+            if (t > Maxcode)
+                break;
+            frm_nxt += 4;
         }
     }
     return static_cast<int>(frm_nxt - frm);
 }
 
+static
+codecvt_base::result
+ucs2_to_utf16be(const uint16_t* frm, const uint16_t* frm_end, const uint16_t*& frm_nxt,
+                uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
+{
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
+    {
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xFE);
+        *to_nxt++ = static_cast<uint8_t>(0xFF);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint16_t wc = *frm_nxt;
+        if ((wc & 0xF800) == 0xD800 || wc > Maxcode)
+            return codecvt_base::error;
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(wc >> 8);
+        *to_nxt++ = static_cast<uint8_t>(wc);
+    }
+    return codecvt_base::ok;
+}
+
+static
+codecvt_base::result
+utf16be_to_ucs2(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+                uint16_t* to, uint16_t* to_end, uint16_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
+{
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFE && frm_nxt[1] == 0xFF)
+            frm_nxt += 2;
+    }
+    for (; frm_nxt < frm_end - 1 && to_nxt < to_end; ++to_nxt)
+    {
+        uint16_t c1 = frm_nxt[0] << 8 | frm_nxt[1];
+        if ((c1 & 0xF800) == 0xD800 || c1 > Maxcode)
+            return codecvt_base::error;
+        *to_nxt = c1;
+        frm_nxt += 2;
+    }
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
+}
+
+static
+int
+utf16be_to_ucs2_length(const uint8_t* frm, const uint8_t* frm_end,
+                       size_t mx, unsigned long Maxcode = 0x10FFFF,
+                       codecvt_mode mode = codecvt_mode(0))
+{
+    const uint8_t* frm_nxt = frm;
+    frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFE && frm_nxt[1] == 0xFF)
+            frm_nxt += 2;
+    }
+    for (size_t nchar16_t = 0; frm_nxt < frm_end - 1 && nchar16_t < mx; ++nchar16_t)
+    {
+        uint16_t c1 = frm_nxt[0] << 8 | frm_nxt[1];
+        if ((c1 & 0xF800) == 0xD800 || c1 > Maxcode)
+            break;
+        frm_nxt += 2;
+    }
+    return static_cast<int>(frm_nxt - frm);
+}
+
+static
+codecvt_base::result
+ucs2_to_utf16le(const uint16_t* frm, const uint16_t* frm_end, const uint16_t*& frm_nxt,
+                uint8_t* to, uint8_t* to_end, uint8_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
+{
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & generate_header)
+    {
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(0xFF);
+        *to_nxt++ = static_cast<uint8_t>(0xFE);
+    }
+    for (; frm_nxt < frm_end; ++frm_nxt)
+    {
+        uint16_t wc = *frm_nxt;
+        if ((wc & 0xF800) == 0xD800 || wc > Maxcode)
+            return codecvt_base::error;
+        if (to_end-to_nxt < 2)
+            return codecvt_base::partial;
+        *to_nxt++ = static_cast<uint8_t>(wc);
+        *to_nxt++ = static_cast<uint8_t>(wc >> 8);
+    }
+    return codecvt_base::ok;
+}
+
+static
+codecvt_base::result
+utf16le_to_ucs2(const uint8_t* frm, const uint8_t* frm_end, const uint8_t*& frm_nxt,
+                uint16_t* to, uint16_t* to_end, uint16_t*& to_nxt,
+                unsigned long Maxcode = 0x10FFFF, codecvt_mode mode = codecvt_mode(0))
+{
+    frm_nxt = frm;
+    to_nxt = to;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFF && frm_nxt[1] == 0xFE)
+            frm_nxt += 2;
+    }
+    for (; frm_nxt < frm_end - 1 && to_nxt < to_end; ++to_nxt)
+    {
+        uint16_t c1 = frm_nxt[1] << 8 | frm_nxt[0];
+        if ((c1 & 0xF800) == 0xD800 || c1 > Maxcode)
+            return codecvt_base::error;
+        *to_nxt = c1;
+        frm_nxt += 2;
+    }
+    return frm_nxt < frm_end ? codecvt_base::partial : codecvt_base::ok;
+}
+
+static
+int
+utf16le_to_ucs2_length(const uint8_t* frm, const uint8_t* frm_end,
+                       size_t mx, unsigned long Maxcode = 0x10FFFF,
+                       codecvt_mode mode = codecvt_mode(0))
+{
+    const uint8_t* frm_nxt = frm;
+    frm_nxt = frm;
+    if (mode & consume_header)
+    {
+        if (frm_end-frm_nxt >= 2 && frm_nxt[0] == 0xFF && frm_nxt[1] == 0xFE)
+            frm_nxt += 2;
+    }
+    for (size_t nchar16_t = 0; frm_nxt < frm_end - 1 && nchar16_t < mx; ++nchar16_t)
+    {
+        uint16_t c1 = frm_nxt[1] << 8 | frm_nxt[0];
+        if ((c1 & 0xF800) == 0xD800 || c1 > Maxcode)
+            break;
+        frm_nxt += 2;
+    }
+    return static_cast<int>(frm_nxt - frm);
+}
+
+// template <> class codecvt<char16_t, char, mbstate_t>
+
+locale::id codecvt<char16_t, char, mbstate_t>::id; 
+
+codecvt<char16_t, char, mbstate_t>::~codecvt()
+{
+}
+
+codecvt<char16_t, char, mbstate_t>::result
+codecvt<char16_t, char, mbstate_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt, 
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint16_t* _frm = reinterpret_cast<const uint16_t*>(frm);
+    const uint16_t* _frm_end = reinterpret_cast<const uint16_t*>(frm_end);
+    const uint16_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = utf16_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+codecvt<char16_t, char, mbstate_t>::result
+codecvt<char16_t, char, mbstate_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt, 
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint16_t* _to = reinterpret_cast<uint16_t*>(to);
+    uint16_t* _to_end = reinterpret_cast<uint16_t*>(to_end);
+    uint16_t* _to_nxt = _to;
+    result r = utf8_to_utf16(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+codecvt<char16_t, char, mbstate_t>::result
+codecvt<char16_t, char, mbstate_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+codecvt<char16_t, char, mbstate_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+codecvt<char16_t, char, mbstate_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+codecvt<char16_t, char, mbstate_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_utf16_length(_frm, _frm_end, mx);
+}
+
+int
+codecvt<char16_t, char, mbstate_t>::do_max_length() const throw()
+{
+    return 4;
+}
+
+// template <> class codecvt<char32_t, char, mbstate_t>
+
+locale::id codecvt<char32_t, char, mbstate_t>::id; 
+
+codecvt<char32_t, char, mbstate_t>::~codecvt()
+{
+}
+
+codecvt<char32_t, char, mbstate_t>::result
+codecvt<char32_t, char, mbstate_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt, 
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+codecvt<char32_t, char, mbstate_t>::result
+codecvt<char32_t, char, mbstate_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt, 
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf8_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+codecvt<char32_t, char, mbstate_t>::result
+codecvt<char32_t, char, mbstate_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
 int
-codecvt<char32_t, char16_t, mbstate_t>::do_max_length() const throw()
+codecvt<char32_t, char, mbstate_t>::do_encoding() const throw()
 {
+    return 0;
+}
+
+bool
+codecvt<char32_t, char, mbstate_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+codecvt<char32_t, char, mbstate_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_ucs4_length(_frm, _frm_end, mx);
+}
+
+int
+codecvt<char32_t, char, mbstate_t>::do_max_length() const throw()
+{
+    return 4;
+}
+
+// __codecvt_utf8<wchar_t>
+
+__codecvt_utf8<wchar_t>::result
+__codecvt_utf8<wchar_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<wchar_t>::result
+__codecvt_utf8<wchar_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf8_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<wchar_t>::result
+__codecvt_utf8<wchar_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8<wchar_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8<wchar_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8<wchar_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8<wchar_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 7;
+    return 4;
+}
+
+// __codecvt_utf8<char16_t>
+
+__codecvt_utf8<char16_t>::result
+__codecvt_utf8<char16_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint16_t* _frm = reinterpret_cast<const uint16_t*>(frm);
+    const uint16_t* _frm_end = reinterpret_cast<const uint16_t*>(frm_end);
+    const uint16_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs2_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<char16_t>::result
+__codecvt_utf8<char16_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint16_t* _to = reinterpret_cast<uint16_t*>(to);
+    uint16_t* _to_end = reinterpret_cast<uint16_t*>(to_end);
+    uint16_t* _to_nxt = _to;
+    result r = utf8_to_ucs2(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<char16_t>::result
+__codecvt_utf8<char16_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8<char16_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8<char16_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8<char16_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_ucs2_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8<char16_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 6;
+    return 3;
+}
+
+// __codecvt_utf8<char32_t>
+
+__codecvt_utf8<char32_t>::result
+__codecvt_utf8<char32_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<char32_t>::result
+__codecvt_utf8<char32_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf8_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                            _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8<char32_t>::result
+__codecvt_utf8<char32_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8<char32_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8<char32_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8<char32_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8<char32_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 7;
+    return 4;
+}
+
+// __codecvt_utf16<wchar_t, false>
+
+__codecvt_utf16<wchar_t, false>::result
+__codecvt_utf16<wchar_t, false>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf16be(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<wchar_t, false>::result
+__codecvt_utf16<wchar_t, false>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf16be_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<wchar_t, false>::result
+__codecvt_utf16<wchar_t, false>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<wchar_t, false>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<wchar_t, false>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf16<wchar_t, false>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16be_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<wchar_t, false>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 6;
+    return 4;
+}
+
+// __codecvt_utf16<wchar_t, true>
+
+__codecvt_utf16<wchar_t, true>::result
+__codecvt_utf16<wchar_t, true>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf16le(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<wchar_t, true>::result
+__codecvt_utf16<wchar_t, true>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf16le_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<wchar_t, true>::result
+__codecvt_utf16<wchar_t, true>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<wchar_t, true>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<wchar_t, true>::do_always_noconv() const throw()
+{
+    return true;
+}
+
+int
+__codecvt_utf16<wchar_t, true>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16le_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<wchar_t, true>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 6;
+    return 4;
+}
+
+// __codecvt_utf16<char16_t, false>
+
+__codecvt_utf16<char16_t, false>::result
+__codecvt_utf16<char16_t, false>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint16_t* _frm = reinterpret_cast<const uint16_t*>(frm);
+    const uint16_t* _frm_end = reinterpret_cast<const uint16_t*>(frm_end);
+    const uint16_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs2_to_utf16be(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char16_t, false>::result
+__codecvt_utf16<char16_t, false>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint16_t* _to = reinterpret_cast<uint16_t*>(to);
+    uint16_t* _to_end = reinterpret_cast<uint16_t*>(to_end);
+    uint16_t* _to_nxt = _to;
+    result r = utf16be_to_ucs2(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char16_t, false>::result
+__codecvt_utf16<char16_t, false>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<char16_t, false>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<char16_t, false>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf16<char16_t, false>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16be_to_ucs2_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<char16_t, false>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 4;
     return 2;
 }
 
+// __codecvt_utf16<char16_t, true>
+
+__codecvt_utf16<char16_t, true>::result
+__codecvt_utf16<char16_t, true>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint16_t* _frm = reinterpret_cast<const uint16_t*>(frm);
+    const uint16_t* _frm_end = reinterpret_cast<const uint16_t*>(frm_end);
+    const uint16_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs2_to_utf16le(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char16_t, true>::result
+__codecvt_utf16<char16_t, true>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint16_t* _to = reinterpret_cast<uint16_t*>(to);
+    uint16_t* _to_end = reinterpret_cast<uint16_t*>(to_end);
+    uint16_t* _to_nxt = _to;
+    result r = utf16le_to_ucs2(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char16_t, true>::result
+__codecvt_utf16<char16_t, true>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<char16_t, true>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<char16_t, true>::do_always_noconv() const throw()
+{
+    return true;
+}
+
+int
+__codecvt_utf16<char16_t, true>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16le_to_ucs2_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<char16_t, true>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 4;
+    return 2;
+}
+
+// __codecvt_utf16<char32_t, false>
+
+__codecvt_utf16<char32_t, false>::result
+__codecvt_utf16<char32_t, false>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf16be(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char32_t, false>::result
+__codecvt_utf16<char32_t, false>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf16be_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char32_t, false>::result
+__codecvt_utf16<char32_t, false>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<char32_t, false>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<char32_t, false>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf16<char32_t, false>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16be_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<char32_t, false>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 6;
+    return 4;
+}
+
+// __codecvt_utf16<char32_t, true>
+
+__codecvt_utf16<char32_t, true>::result
+__codecvt_utf16<char32_t, true>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = ucs4_to_utf16le(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char32_t, true>::result
+__codecvt_utf16<char32_t, true>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf16le_to_ucs4(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                               _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf16<char32_t, true>::result
+__codecvt_utf16<char32_t, true>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf16<char32_t, true>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf16<char32_t, true>::do_always_noconv() const throw()
+{
+    return true;
+}
+
+int
+__codecvt_utf16<char32_t, true>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf16le_to_ucs4_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf16<char32_t, true>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 6;
+    return 4;
+}
+
+// __codecvt_utf8_utf16<wchar_t>
+
+__codecvt_utf8_utf16<wchar_t>::result
+__codecvt_utf8_utf16<wchar_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = utf16_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<wchar_t>::result
+__codecvt_utf8_utf16<wchar_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf8_to_utf16(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<wchar_t>::result
+__codecvt_utf8_utf16<wchar_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8_utf16<wchar_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8_utf16<wchar_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8_utf16<wchar_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_utf16_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8_utf16<wchar_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 7;
+    return 4;
+}
+
+// __codecvt_utf8_utf16<char16_t>
+
+__codecvt_utf8_utf16<char16_t>::result
+__codecvt_utf8_utf16<char16_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint16_t* _frm = reinterpret_cast<const uint16_t*>(frm);
+    const uint16_t* _frm_end = reinterpret_cast<const uint16_t*>(frm_end);
+    const uint16_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = utf16_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<char16_t>::result
+__codecvt_utf8_utf16<char16_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint16_t* _to = reinterpret_cast<uint16_t*>(to);
+    uint16_t* _to_end = reinterpret_cast<uint16_t*>(to_end);
+    uint16_t* _to_nxt = _to;
+    result r = utf8_to_utf16(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<char16_t>::result
+__codecvt_utf8_utf16<char16_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8_utf16<char16_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8_utf16<char16_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8_utf16<char16_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_utf16_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8_utf16<char16_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 7;
+    return 4;
+}
+
+// __codecvt_utf8_utf16<char32_t>
+
+__codecvt_utf8_utf16<char32_t>::result
+__codecvt_utf8_utf16<char32_t>::do_out(state_type&,
+    const intern_type* frm, const intern_type* frm_end, const intern_type*& frm_nxt,
+    extern_type* to, extern_type* to_end, extern_type*& to_nxt) const
+{
+    const uint32_t* _frm = reinterpret_cast<const uint32_t*>(frm);
+    const uint32_t* _frm_end = reinterpret_cast<const uint32_t*>(frm_end);
+    const uint32_t* _frm_nxt = _frm;
+    uint8_t* _to = reinterpret_cast<uint8_t*>(to);
+    uint8_t* _to_end = reinterpret_cast<uint8_t*>(to_end);
+    uint8_t* _to_nxt = _to;
+    result r = utf16_to_utf8(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<char32_t>::result
+__codecvt_utf8_utf16<char32_t>::do_in(state_type&,
+    const extern_type* frm, const extern_type* frm_end, const extern_type*& frm_nxt,
+    intern_type* to, intern_type* to_end, intern_type*& to_nxt) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    const uint8_t* _frm_nxt = _frm;
+    uint32_t* _to = reinterpret_cast<uint32_t*>(to);
+    uint32_t* _to_end = reinterpret_cast<uint32_t*>(to_end);
+    uint32_t* _to_nxt = _to;
+    result r = utf8_to_utf16(_frm, _frm_end, _frm_nxt, _to, _to_end, _to_nxt,
+                             _Maxcode_, _Mode_);
+    frm_nxt = frm + (_frm_nxt - _frm);
+    to_nxt = to + (_to_nxt - _to);
+    return r;
+}
+
+__codecvt_utf8_utf16<char32_t>::result
+__codecvt_utf8_utf16<char32_t>::do_unshift(state_type&,
+    extern_type* to, extern_type*, extern_type*& to_nxt) const
+{
+    to_nxt = to;
+    return noconv;
+}
+
+int
+__codecvt_utf8_utf16<char32_t>::do_encoding() const throw()
+{
+    return 0;
+}
+
+bool
+__codecvt_utf8_utf16<char32_t>::do_always_noconv() const throw()
+{
+    return false;
+}
+
+int
+__codecvt_utf8_utf16<char32_t>::do_length(state_type&,
+    const extern_type* frm, const extern_type* frm_end, size_t mx) const
+{
+    const uint8_t* _frm = reinterpret_cast<const uint8_t*>(frm);
+    const uint8_t* _frm_end = reinterpret_cast<const uint8_t*>(frm_end);
+    return utf8_to_utf16_length(_frm, _frm_end, mx, _Maxcode_, _Mode_);
+}
+
+int
+__codecvt_utf8_utf16<char32_t>::do_max_length() const throw()
+{
+    if (_Mode_ & consume_header)
+        return 7;
+    return 4;
+}
+
 // __narrow_to_utf8<16>
 
 __narrow_to_utf8<16>::~__narrow_to_utf8()