NT4/private/windows/winnls/utf.c
2020-09-30 17:12:29 +02:00

902 lines
22 KiB
C

/*++
Copyright (c) 1991-1996, Microsoft Corporation All rights reserved.
Module Name:
utf.c
Abstract:
This file contains functions that convert UTF strings to Unicode
strings and Unicode string to UTF strings.
Revision History:
02-06-96 JulieB Created.
--*/
//
// Include Files.
//
#include "nls.h"
#include "utf.h"
//
// Forward Declarations.
//
int
UTF7ToUnicode(
LPCSTR lpSrcStr,
int cchSrc,
LPWSTR lpDestStr,
int cchDest);
int
UTF8ToUnicode(
LPCSTR lpSrcStr,
int cchSrc,
LPWSTR lpDestStr,
int cchDest);
int
UnicodeToUTF7(
LPCWSTR lpSrcStr,
int cchSrc,
LPSTR lpDestStr,
int cchDest);
int
UnicodeToUTF8(
LPCWSTR lpSrcStr,
int cchSrc,
LPSTR lpDestStr,
int cchDest);
//-------------------------------------------------------------------------//
// EXTERNAL ROUTINES //
//-------------------------------------------------------------------------//
////////////////////////////////////////////////////////////////////////////
//
// UTFToUnicode
//
// Maps a UTF character string to its wide character string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UTFToUnicode(
UINT CodePage,
DWORD dwFlags,
LPCSTR lpMultiByteStr,
int cchMultiByte,
LPWSTR lpWideCharStr,
int cchWideChar)
{
int rc = 0;
//
// Invalid Parameter Check:
// - validate code page
// - length of MB string is 0
// - wide char buffer size is negative
// - MB string is NULL
// - length of WC string is NOT zero AND
// (WC string is NULL OR src and dest pointers equal)
//
if ( (CodePage < CP_UTF7) || (CodePage > CP_UTF8) ||
(cchMultiByte == 0) || (cchWideChar < 0) ||
(lpMultiByteStr == NULL) ||
((cchWideChar != 0) &&
((lpWideCharStr == NULL) ||
(lpMultiByteStr == (LPSTR)lpWideCharStr))) )
{
SetLastError(ERROR_INVALID_PARAMETER);
return (0);
}
//
// Invalid Flags Check:
// - flags not 0
//
if (dwFlags != 0)
{
SetLastError(ERROR_INVALID_FLAGS);
return (0);
}
//
// If cchMultiByte is -1, then the string is null terminated and we
// need to get the length of the string. Add one to the length to
// include the null termination. (This will always be at least 1.)
//
if (cchMultiByte <= -1)
{
cchMultiByte = strlen(lpMultiByteStr) + 1;
}
switch (CodePage)
{
case ( CP_UTF7 ) :
{
rc = UTF7ToUnicode( lpMultiByteStr,
cchMultiByte,
lpWideCharStr,
cchWideChar );
break;
}
case ( CP_UTF8 ) :
{
rc = UTF8ToUnicode( lpMultiByteStr,
cchMultiByte,
lpWideCharStr,
cchWideChar );
break;
}
}
return (rc);
}
////////////////////////////////////////////////////////////////////////////
//
// UnicodeToUTF
//
// Maps a Unicode character string to its UTF string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UnicodeToUTF(
UINT CodePage,
DWORD dwFlags,
LPCWSTR lpWideCharStr,
int cchWideChar,
LPSTR lpMultiByteStr,
int cchMultiByte,
LPCSTR lpDefaultChar,
LPBOOL lpUsedDefaultChar)
{
int rc = 0;
//
// Invalid Parameter Check:
// - validate code page
// - length of WC string is 0
// - multibyte buffer size is negative
// - WC string is NULL
// - length of WC string is NOT zero AND
// (MB string is NULL OR src and dest pointers equal)
// - lpDefaultChar and lpUsedDefaultChar not NULL
//
if ( (CodePage < CP_UTF7) || (CodePage > CP_UTF8) ||
(cchWideChar == 0) || (cchMultiByte < 0) ||
(lpWideCharStr == NULL) ||
((cchMultiByte != 0) &&
((lpMultiByteStr == NULL) ||
(lpWideCharStr == (LPWSTR)lpMultiByteStr))) ||
(lpDefaultChar != NULL) || (lpUsedDefaultChar != NULL) )
{
SetLastError(ERROR_INVALID_PARAMETER);
return (0);
}
//
// Invalid Flags Check:
// - flags not 0
//
if (dwFlags != 0)
{
SetLastError(ERROR_INVALID_FLAGS);
return (0);
}
//
// If cchWideChar is -1, then the string is null terminated and we
// need to get the length of the string. Add one to the length to
// include the null termination. (This will always be at least 1.)
//
if (cchWideChar <= -1)
{
cchWideChar = NlsStrLenW(lpWideCharStr) + 1;
}
switch (CodePage)
{
case ( CP_UTF7 ) :
{
rc = UnicodeToUTF7( lpWideCharStr,
cchWideChar,
lpMultiByteStr,
cchMultiByte );
break;
}
case ( CP_UTF8 ) :
{
rc = UnicodeToUTF8( lpWideCharStr,
cchWideChar,
lpMultiByteStr,
cchMultiByte );
break;
}
}
return (rc);
}
//-------------------------------------------------------------------------//
// INTERNAL ROUTINES //
//-------------------------------------------------------------------------//
////////////////////////////////////////////////////////////////////////////
//
// UTF7ToUnicode
//
// Maps a UTF-7 character string to its wide character string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UTF7ToUnicode(
LPCSTR lpSrcStr,
int cchSrc,
LPWSTR lpDestStr,
int cchDest)
{
LPCSTR pUTF7 = lpSrcStr;
BOOL fShift = FALSE;
DWORD dwBit = 0; // 32-bit buffer to hold temporary bits
int iPos = 0; // 6-bit position pointer in the buffer
int cchWC = 0; // # of Unicode code points generated
while ((cchSrc--) && ((cchDest == 0) || (cchWC < cchDest)))
{
if (*pUTF7 > ASCII)
{
//
// Error - non ASCII char, so zero extend it.
//
if (cchDest)
{
lpDestStr[cchWC] = (WCHAR)*pUTF7;
}
cchWC++;
}
else if (!fShift)
{
//
// Not in shifted sequence.
//
if (*pUTF7 == SHIFT_IN)
{
if (cchSrc && (pUTF7[1] == SHIFT_OUT))
{
//
// "+-" means "+"
//
if (cchDest)
{
lpDestStr[cchWC] = (WCHAR)*pUTF7;
}
pUTF7++;
cchSrc--;
cchWC++;
}
else
{
//
// Start a new shift sequence.
//
fShift = TRUE;
}
}
else
{
//
// No need to shift.
//
if (cchDest)
{
lpDestStr[cchWC] = (WCHAR)*pUTF7;
}
cchWC++;
}
}
else
{
//
// Already in shifted sequence.
//
if (nBitBase64[*pUTF7] == -1)
{
//
// Any non Base64 char also ends shift state.
//
if (*pUTF7 != SHIFT_OUT)
{
//
// Not "-", so write it to the buffer.
//
if (cchDest)
{
lpDestStr[cchWC] = (WCHAR)*pUTF7;
}
cchWC++;
}
//
// Reset bits.
//
fShift = FALSE;
dwBit = 0;
iPos = 0;
}
else
{
//
// Store the bits in the 6-bit buffer and adjust the
// position pointer.
//
dwBit |= ((DWORD)nBitBase64[*pUTF7]) << (26 - iPos);
iPos += 6;
}
//
// Output the 16-bit Unicode value.
//
while (iPos >= 16)
{
if (cchDest)
{
if (cchWC < cchDest)
{
lpDestStr[cchWC] = (WCHAR)(dwBit >> 16);
}
else
{
break;
}
}
cchWC++;
dwBit <<= 16;
iPos -= 16;
}
if (iPos >= 16)
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
pUTF7++;
}
//
// Make sure the destination buffer was large enough.
//
if (cchDest && (cchSrc >= 0))
{
SetLastError(ERROR_INSUFFICIENT_BUFFER);
return (0);
}
//
// Return the number of Unicode characters written.
//
return (cchWC);
}
////////////////////////////////////////////////////////////////////////////
//
// UTF8ToUnicode
//
// Maps a UTF-8 character string to its wide character string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UTF8ToUnicode(
LPCSTR lpSrcStr,
int cchSrc,
LPWSTR lpDestStr,
int cchDest)
{
int nTB = 0; // # trail bytes to follow
int cchWC = 0; // # of Unicode code points generated
LPCSTR pUTF8 = lpSrcStr;
char UTF8;
while ((cchSrc--) && ((cchDest == 0) || (cchWC < cchDest)))
{
//
// See if there are any trail bytes.
//
if (BIT7(*pUTF8) == 0)
{
//
// Found ASCII.
//
if (cchDest)
{
lpDestStr[cchWC] = (WCHAR)*pUTF8;
}
cchWC++;
}
else if (BIT6(*pUTF8) == 0)
{
//
// Found a trail byte.
// Note : Ignore the trail byte if there was no lead byte.
//
if (nTB != 0)
{
//
// Decrement the trail byte counter.
//
nTB--;
//
// Make room for the trail byte and add the trail byte
// value.
//
if (cchDest)
{
lpDestStr[cchWC] <<= 6;
lpDestStr[cchWC] |= LOWER_6_BIT(*pUTF8);
}
if (nTB == 0)
{
//
// End of sequence. Advance the output counter.
//
cchWC++;
}
}
}
else
{
//
// Found a lead byte.
//
if (nTB > 0)
{
//
// Error - previous sequence not finished.
//
nTB = 0;
cchWC++;
}
else
{
//
// Calculate the number of bytes to follow.
// Look for the first 0 from left to right.
//
UTF8 = *pUTF8;
while (BIT7(UTF8) != 0)
{
UTF8 <<= 1;
nTB++;
}
//
// Store the value from the first byte and decrement
// the number of bytes to follow.
//
if (cchDest)
{
lpDestStr[cchWC] = UTF8 >> nTB;
}
nTB--;
}
}
pUTF8++;
}
//
// Make sure the destination buffer was large enough.
//
if (cchDest && (cchSrc >= 0))
{
SetLastError(ERROR_INSUFFICIENT_BUFFER);
return (0);
}
//
// Return the number of Unicode characters written.
//
return (cchWC);
}
////////////////////////////////////////////////////////////////////////////
//
// UnicodeToUTF7
//
// Maps a Unicode character string to its UTF-7 string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UnicodeToUTF7(
LPCWSTR lpSrcStr,
int cchSrc,
LPSTR lpDestStr,
int cchDest)
{
LPCWSTR lpWC = lpSrcStr;
BOOL fShift = FALSE;
DWORD dwBit = 0; // 32-bit buffer
int iPos = 0; // 6-bit position in buffer
int cchU7 = 0; // # of UTF7 chars generated
while ((cchSrc--) && ((cchDest == 0) || (cchU7 < cchDest)))
{
if ((*lpWC > ASCII) || (fShiftChar[*lpWC]))
{
//
// Need shift. Store 16 bits in buffer.
//
dwBit |= ((DWORD)*lpWC) << (16 - iPos);
iPos += 16;
if (!fShift)
{
//
// Not in shift state, so add "+".
//
if (cchDest)
{
lpDestStr[cchU7] = SHIFT_IN;
}
cchU7++;
//
// Go into shift state.
//
fShift = TRUE;
}
//
// Output 6 bits at a time as Base64 chars.
//
while (iPos >= 6)
{
if (cchDest)
{
if (cchU7 < cchDest)
{
//
// 26 = 32 - 6
//
lpDestStr[cchU7] = cBase64[(int)(dwBit >> 26)];
}
else
{
break;
}
}
cchU7++;
dwBit <<= 6; // remove from bit buffer
iPos -= 6; // adjust position pointer
}
if (iPos >= 6)
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
else
{
//
// No need to shift.
//
if (fShift)
{
//
// End the shift sequence.
//
fShift = FALSE;
if (iPos != 0)
{
//
// Some bits left in dwBit.
//
if (cchDest)
{
if ((cchU7 + 1) < cchDest)
{
lpDestStr[cchU7++] = cBase64[(int)(dwBit >> 26)];
lpDestStr[cchU7++] = SHIFT_OUT;
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
else
{
cchU7 += 2;
}
dwBit = 0; // reset bit buffer
iPos = 0; // reset postion pointer
}
else
{
//
// Simply end the shift sequence.
//
if (cchDest)
{
lpDestStr[cchU7++] = SHIFT_OUT;
}
else
{
cchU7++;
}
}
}
//
// Write the character to the buffer.
// If the character is "+", then write "+-".
//
if (cchDest)
{
if (cchU7 < cchDest)
{
lpDestStr[cchU7++] = (char)*lpWC;
if (*lpWC == SHIFT_IN)
{
if (cchU7 < cchDest)
{
lpDestStr[cchU7++] = SHIFT_OUT;
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
else
{
cchU7++;
if (*lpWC == SHIFT_IN)
{
cchU7++;
}
}
}
lpWC++;
}
//
// See if we're still in the shift state.
//
if (fShift)
{
if (iPos != 0)
{
//
// Some bits left in dwBit.
//
if (cchDest)
{
if ((cchU7 + 1) < cchDest)
{
lpDestStr[cchU7++] = cBase64[(int)(dwBit >> 26)];
lpDestStr[cchU7++] = SHIFT_OUT;
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
}
}
else
{
cchU7 += 2;
}
}
else
{
//
// Simply end the shift sequence.
//
if (cchDest)
{
lpDestStr[cchU7++] = SHIFT_OUT;
}
else
{
cchU7++;
}
}
}
//
// Make sure the destination buffer was large enough.
//
if (cchDest && (cchSrc >= 0))
{
SetLastError(ERROR_INSUFFICIENT_BUFFER);
return (0);
}
//
// Return the number of UTF-7 characters written.
//
return (cchU7);
}
////////////////////////////////////////////////////////////////////////////
//
// UnicodeToUTF8
//
// Maps a Unicode character string to its UTF-8 string counterpart.
//
// 02-06-96 JulieB Created.
////////////////////////////////////////////////////////////////////////////
int UnicodeToUTF8(
LPCWSTR lpSrcStr,
int cchSrc,
LPSTR lpDestStr,
int cchDest)
{
LPCWSTR lpWC = lpSrcStr;
int cchU8 = 0; // # of UTF8 chars generated
while ((cchSrc--) && ((cchDest == 0) || (cchU8 < cchDest)))
{
if (*lpWC <= ASCII)
{
//
// Found ASCII.
//
if (cchDest)
{
lpDestStr[cchU8] = (char)*lpWC;
}
cchU8++;
}
else if (*lpWC <= UTF8_2_MAX)
{
//
// Found 2 byte sequence if < 0x07ff (11 bits).
//
if (cchDest)
{
if ((cchU8 + 1) < cchDest)
{
//
// Use upper 5 bits in first byte.
// Use lower 6 bits in second byte.
//
lpDestStr[cchU8++] = UTF8_1ST_OF_2 | (*lpWC >> 6);
lpDestStr[cchU8++] = UTF8_TRAIL | LOWER_6_BIT(*lpWC);
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
else
{
cchU8 += 2;
}
}
else
{
//
// Found 3 byte sequence.
//
if (cchDest)
{
if ((cchU8 + 2) < cchDest)
{
//
// Use upper 4 bits in first byte.
// Use middle 6 bits in second byte.
// Use lower 6 bits in third byte.
//
lpDestStr[cchU8++] = UTF8_1ST_OF_3 | (*lpWC >> 12);
lpDestStr[cchU8++] = UTF8_TRAIL | MIDDLE_6_BIT(*lpWC);
lpDestStr[cchU8++] = UTF8_TRAIL | LOWER_6_BIT(*lpWC);
}
else
{
//
// Error - buffer too small.
//
cchSrc++;
break;
}
}
else
{
cchU8 += 3;
}
}
lpWC++;
}
//
// Make sure the destination buffer was large enough.
//
if (cchDest && (cchSrc >= 0))
{
SetLastError(ERROR_INSUFFICIENT_BUFFER);
return (0);
}
//
// Return the number of UTF-8 characters written.
//
return (cchU8);
}