reactos/sdk/lib/rtl/utf8.c

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/*
* PROJECT: ReactOS Kernel - Vista+ APIs
* LICENSE: GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
* PURPOSE: Rtl functions of Vista+
* COPYRIGHT: 2016 Thomas Faber <thomas.faber@reactos.org>
*/
/* INCLUDES ******************************************************************/
#include <rtl_vista.h>
#define NDEBUG
#include <debug.h>
/* FUNCTIONS *****************************************************************/
/******************************************************************************
* RtlUnicodeToUTF8N [NTDLL.@]
*/
NTSTATUS NTAPI RtlUnicodeToUTF8N(CHAR *utf8_dest, ULONG utf8_bytes_max,
ULONG *utf8_bytes_written,
const WCHAR *uni_src, ULONG uni_bytes)
{
NTSTATUS status;
ULONG i;
ULONG written;
ULONG ch;
BYTE utf8_ch[4];
ULONG utf8_ch_len;
if (!uni_src)
return STATUS_INVALID_PARAMETER_4;
if (!utf8_bytes_written)
return STATUS_INVALID_PARAMETER;
if (utf8_dest && uni_bytes % sizeof(WCHAR))
return STATUS_INVALID_PARAMETER_5;
written = 0;
status = STATUS_SUCCESS;
for (i = 0; i < uni_bytes / sizeof(WCHAR); i++)
{
/* decode UTF-16 into ch */
ch = uni_src[i];
if (ch >= 0xdc00 && ch <= 0xdfff)
{
ch = 0xfffd;
status = STATUS_SOME_NOT_MAPPED;
}
else if (ch >= 0xd800 && ch <= 0xdbff)
{
if (i + 1 < uni_bytes / sizeof(WCHAR))
{
ch -= 0xd800;
ch <<= 10;
if (uni_src[i + 1] >= 0xdc00 && uni_src[i + 1] <= 0xdfff)
{
ch |= uni_src[i + 1] - 0xdc00;
ch += 0x010000;
i++;
}
else
{
ch = 0xfffd;
status = STATUS_SOME_NOT_MAPPED;
}
}
else
{
ch = 0xfffd;
status = STATUS_SOME_NOT_MAPPED;
}
}
/* encode ch as UTF-8 */
ASSERT(ch <= 0x10ffff);
if (ch < 0x80)
{
utf8_ch[0] = ch & 0x7f;
utf8_ch_len = 1;
}
else if (ch < 0x800)
{
utf8_ch[0] = 0xc0 | (ch >> 6 & 0x1f);
utf8_ch[1] = 0x80 | (ch >> 0 & 0x3f);
utf8_ch_len = 2;
}
else if (ch < 0x10000)
{
utf8_ch[0] = 0xe0 | (ch >> 12 & 0x0f);
utf8_ch[1] = 0x80 | (ch >> 6 & 0x3f);
utf8_ch[2] = 0x80 | (ch >> 0 & 0x3f);
utf8_ch_len = 3;
}
else if (ch < 0x200000)
{
utf8_ch[0] = 0xf0 | (ch >> 18 & 0x07);
utf8_ch[1] = 0x80 | (ch >> 12 & 0x3f);
utf8_ch[2] = 0x80 | (ch >> 6 & 0x3f);
utf8_ch[3] = 0x80 | (ch >> 0 & 0x3f);
utf8_ch_len = 4;
}
if (!utf8_dest)
{
written += utf8_ch_len;
continue;
}
if (utf8_bytes_max >= utf8_ch_len)
{
memcpy(utf8_dest, utf8_ch, utf8_ch_len);
utf8_dest += utf8_ch_len;
utf8_bytes_max -= utf8_ch_len;
written += utf8_ch_len;
}
else
{
utf8_bytes_max = 0;
status = STATUS_BUFFER_TOO_SMALL;
}
}
*utf8_bytes_written = written;
return status;
}
/******************************************************************************
* RtlUTF8ToUnicodeN [NTDLL.@]
*/
NTSTATUS NTAPI RtlUTF8ToUnicodeN(WCHAR *uni_dest, ULONG uni_bytes_max,
ULONG *uni_bytes_written,
const CHAR *utf8_src, ULONG utf8_bytes)
{
NTSTATUS status;
ULONG i, j;
ULONG written;
ULONG ch;
ULONG utf8_trail_bytes;
WCHAR utf16_ch[3];
ULONG utf16_ch_len;
if (!utf8_src)
return STATUS_INVALID_PARAMETER_4;
if (!uni_bytes_written)
return STATUS_INVALID_PARAMETER;
written = 0;
status = STATUS_SUCCESS;
for (i = 0; i < utf8_bytes; i++)
{
/* read UTF-8 lead byte */
ch = (BYTE)utf8_src[i];
utf8_trail_bytes = 0;
if (ch >= 0xf5)
{
ch = 0xfffd;
status = STATUS_SOME_NOT_MAPPED;
}
else if (ch >= 0xf0)
{
ch &= 0x07;
utf8_trail_bytes = 3;
}
else if (ch >= 0xe0)
{
ch &= 0x0f;
utf8_trail_bytes = 2;
}
else if (ch >= 0xc2)
{
ch &= 0x1f;
utf8_trail_bytes = 1;
}
else if (ch >= 0x80)
{
/* overlong or trail byte */
ch = 0xfffd;
status = STATUS_SOME_NOT_MAPPED;
}
/* read UTF-8 trail bytes */
if (i + utf8_trail_bytes < utf8_bytes)
{
for (j = 0; j < utf8_trail_bytes; j++)
{
if ((utf8_src[i + 1] & 0xc0) == 0x80)
{
ch <<= 6;
ch |= utf8_src[i + 1] & 0x3f;
i++;
}
else
{
ch = 0xfffd;
utf8_trail_bytes = 0;
status = STATUS_SOME_NOT_MAPPED;
break;
}
}
}
else
{
ch = 0xfffd;
utf8_trail_bytes = 0;
status = STATUS_SOME_NOT_MAPPED;
i = utf8_bytes;
}
/* encode ch as UTF-16 */
if ((ch > 0x10ffff) ||
(ch >= 0xd800 && ch <= 0xdfff) ||
(utf8_trail_bytes == 2 && ch < 0x00800) ||
(utf8_trail_bytes == 3 && ch < 0x10000))
{
/* invalid codepoint or overlong encoding */
utf16_ch[0] = 0xfffd;
utf16_ch[1] = 0xfffd;
utf16_ch[2] = 0xfffd;
utf16_ch_len = utf8_trail_bytes;
status = STATUS_SOME_NOT_MAPPED;
}
else if (ch >= 0x10000)
{
/* surrogate pair */
ch -= 0x010000;
utf16_ch[0] = 0xd800 + (ch >> 10 & 0x3ff);
utf16_ch[1] = 0xdc00 + (ch >> 0 & 0x3ff);
utf16_ch_len = 2;
}
else
{
/* single unit */
utf16_ch[0] = ch;
utf16_ch_len = 1;
}
if (!uni_dest)
{
written += utf16_ch_len;
continue;
}
for (j = 0; j < utf16_ch_len; j++)
{
if (uni_bytes_max >= sizeof(WCHAR))
{
*uni_dest++ = utf16_ch[j];
uni_bytes_max -= sizeof(WCHAR);
written++;
}
else
{
uni_bytes_max = 0;
status = STATUS_BUFFER_TOO_SMALL;
}
}
}
*uni_bytes_written = written * sizeof(WCHAR);
return status;
}