1105 lines
26 KiB
C
1105 lines
26 KiB
C
/*++
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Copyright (c) 1991-1999, Microsoft Corporation All rights reserved.
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Module Name:
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utf.c
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Abstract:
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This file contains functions that convert UTF strings to Unicode
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strings and Unicode string to UTF strings.
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External Routines found in this file:
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UTFCPInfo
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UTFToUnicode
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UnicodeToUTF
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Revision History:
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02-06-96 JulieB Created.
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03-20-99 SamerA Surrogate support.
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--*/
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// Include Files.
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#include "nls.h"
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#include "utf.h"
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// Forward Declarations.
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int UTF7ToUnicode(LPCSTR lpSrcStr, int cchSrc, LPWSTR lpDestStr, int cchDest);
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int UTF8ToUnicode(LPCSTR lpSrcStr, int cchSrc, LPWSTR lpDestStr, int cchDest);
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int UnicodeToUTF7(LPCWSTR lpSrcStr, int cchSrc, LPSTR lpDestStr, int cchDest);
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int UnicodeToUTF8(LPCWSTR lpSrcStr, int cchSrc, LPSTR lpDestStr, int cchDest);
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// EXTERNAL ROUTINES //
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// UTFCPInfo
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// Gets the CPInfo for the given UTF code page.
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// 10-23-96 JulieB Created.
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BOOL UTFCPInfo(
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UINT CodePage,
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LPCPINFO lpCPInfo,
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BOOL fExVer)
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{
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int ctr;
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// Invalid Parameter Check:
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// - validate code page
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// - lpCPInfo is NULL
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if ( (CodePage < CP_UTF7) || (CodePage > CP_UTF8) ||
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(lpCPInfo == NULL) )
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{
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SetLastError(ERROR_INVALID_PARAMETER);
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return (0);
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}
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switch (CodePage)
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{
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case ( CP_UTF7 ) :
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{
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lpCPInfo->MaxCharSize = 5;
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break;
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}
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case ( CP_UTF8 ) :
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{
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lpCPInfo->MaxCharSize = 4;
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break;
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}
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}
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(lpCPInfo->DefaultChar)[0] = '?';
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(lpCPInfo->DefaultChar)[1] = (BYTE)0;
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for (ctr = 0; ctr < MAX_LEADBYTES; ctr++)
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{
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(lpCPInfo->LeadByte)[ctr] = (BYTE)0;
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}
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if (fExVer)
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{
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LPCPINFOEXW lpCPInfoEx = (LPCPINFOEXW)lpCPInfo;
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lpCPInfoEx->UnicodeDefaultChar = L'?';
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lpCPInfoEx->CodePage = CodePage;
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}
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return (TRUE);
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}
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// UTFToUnicode
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// Maps a UTF character string to its wide character string counterpart.
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// 02-06-96 JulieB Created.
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int UTFToUnicode(
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UINT CodePage,
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DWORD dwFlags,
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LPCSTR lpMultiByteStr,
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int cbMultiByte,
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LPWSTR lpWideCharStr,
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int cchWideChar)
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{
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int rc = 0;
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// Invalid Parameter Check:
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// - validate code page
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// - length of MB string is 0
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// - wide char buffer size is negative
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// - MB string is NULL
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// - length of WC string is NOT zero AND
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// (WC string is NULL OR src and dest pointers equal)
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if ( (CodePage < CP_UTF7) || (CodePage > CP_UTF8) ||
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(cbMultiByte == 0) || (cchWideChar < 0) ||
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(lpMultiByteStr == NULL) ||
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((cchWideChar != 0) &&
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((lpWideCharStr == NULL) ||
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(lpMultiByteStr == (LPSTR)lpWideCharStr))) )
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{
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SetLastError(ERROR_INVALID_PARAMETER);
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return (0);
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}
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// Invalid Flags Check:
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// - flags not 0
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if (dwFlags != 0)
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{
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SetLastError(ERROR_INVALID_FLAGS);
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return (0);
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}
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// If cbMultiByte is -1, then the string is null terminated and we
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// need to get the length of the string. Add one to the length to
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// include the null termination. (This will always be at least 1.)
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if (cbMultiByte <= -1)
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{
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cbMultiByte = strlen(lpMultiByteStr) + 1;
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}
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switch (CodePage)
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{
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case ( CP_UTF7 ) :
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{
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rc = UTF7ToUnicode( lpMultiByteStr,
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cbMultiByte,
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lpWideCharStr,
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cchWideChar );
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break;
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}
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case ( CP_UTF8 ) :
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{
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rc = UTF8ToUnicode( lpMultiByteStr,
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cbMultiByte,
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lpWideCharStr,
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cchWideChar );
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break;
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}
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}
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return (rc);
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}
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// UnicodeToUTF
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// Maps a Unicode character string to its UTF string counterpart.
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// 02-06-96 JulieB Created.
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int UnicodeToUTF(
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UINT CodePage,
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DWORD dwFlags,
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LPCWSTR lpWideCharStr,
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int cchWideChar,
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LPSTR lpMultiByteStr,
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int cbMultiByte,
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LPCSTR lpDefaultChar,
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LPBOOL lpUsedDefaultChar)
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{
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int rc = 0;
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// Invalid Parameter Check:
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// - validate code page
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// - length of WC string is 0
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// - multibyte buffer size is negative
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// - WC string is NULL
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// - length of WC string is NOT zero AND
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// (MB string is NULL OR src and dest pointers equal)
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// - lpDefaultChar and lpUsedDefaultChar not NULL
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if ( (CodePage < CP_UTF7) || (CodePage > CP_UTF8) ||
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(cchWideChar == 0) || (cbMultiByte < 0) ||
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(lpWideCharStr == NULL) ||
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((cbMultiByte != 0) &&
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((lpMultiByteStr == NULL) ||
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(lpWideCharStr == (LPWSTR)lpMultiByteStr))) ||
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(lpDefaultChar != NULL) || (lpUsedDefaultChar != NULL) )
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{
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SetLastError(ERROR_INVALID_PARAMETER);
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return (0);
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}
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// Invalid Flags Check:
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// - flags not 0
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if (dwFlags != 0)
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{
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SetLastError(ERROR_INVALID_FLAGS);
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return (0);
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}
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// If cchWideChar is -1, then the string is null terminated and we
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// need to get the length of the string. Add one to the length to
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// include the null termination. (This will always be at least 1.)
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if (cchWideChar <= -1)
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{
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cchWideChar = NlsStrLenW(lpWideCharStr) + 1;
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}
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switch (CodePage)
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{
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case ( CP_UTF7 ) :
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{
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rc = UnicodeToUTF7( lpWideCharStr,
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cchWideChar,
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lpMultiByteStr,
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cbMultiByte );
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break;
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}
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case ( CP_UTF8 ) :
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{
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rc = UnicodeToUTF8( lpWideCharStr,
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cchWideChar,
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lpMultiByteStr,
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cbMultiByte );
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break;
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}
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}
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return (rc);
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}
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// INTERNAL ROUTINES //
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// UTF7ToUnicode
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// Maps a UTF-7 character string to its wide character string counterpart.
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// 02-06-96 JulieB Created.
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int UTF7ToUnicode(
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LPCSTR lpSrcStr,
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int cchSrc,
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LPWSTR lpDestStr,
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int cchDest)
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{
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LPCSTR pUTF7 = lpSrcStr;
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BOOL fShift = FALSE;
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DWORD dwBit = 0; // 32-bit buffer to hold temporary bits
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int iPos = 0; // 6-bit position pointer in the buffer
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int cchWC = 0; // # of Unicode code points generated
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while ((cchSrc--) && ((cchDest == 0) || (cchWC < cchDest)))
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{
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if (*pUTF7 > ASCII)
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{
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// Error - non ASCII char, so zero extend it.
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if (cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)*pUTF7;
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}
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cchWC++;
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}
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else if (!fShift)
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{
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// Not in shifted sequence.
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if (*pUTF7 == SHIFT_IN)
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{
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if (cchSrc && (pUTF7[1] == SHIFT_OUT))
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{
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// "+-" means "+"
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if (cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)*pUTF7;
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}
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pUTF7++;
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cchSrc--;
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cchWC++;
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}
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else
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{
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// Start a new shift sequence.
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fShift = TRUE;
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}
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}
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else
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{
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// No need to shift.
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if (cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)*pUTF7;
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}
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cchWC++;
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}
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}
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else
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{
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// Already in shifted sequence.
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if (nBitBase64[*pUTF7] == -1)
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{
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// Any non Base64 char also ends shift state.
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if (*pUTF7 != SHIFT_OUT)
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{
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// Not "-", so write it to the buffer.
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if (cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)*pUTF7;
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}
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cchWC++;
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}
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// Reset bits.
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fShift = FALSE;
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dwBit = 0;
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iPos = 0;
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}
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else
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{
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// Store the bits in the 6-bit buffer and adjust the
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// position pointer.
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dwBit |= ((DWORD)nBitBase64[*pUTF7]) << (26 - iPos);
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iPos += 6;
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}
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// Output the 16-bit Unicode value.
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while (iPos >= 16)
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{
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if (cchDest)
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{
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if (cchWC < cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)(dwBit >> 16);
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}
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else
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{
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break;
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}
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}
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cchWC++;
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dwBit <<= 16;
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iPos -= 16;
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}
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if (iPos >= 16)
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{
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// Error - buffer too small.
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cchSrc++;
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break;
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}
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}
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pUTF7++;
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}
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// Make sure the destination buffer was large enough.
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if (cchDest && (cchSrc >= 0))
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{
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SetLastError(ERROR_INSUFFICIENT_BUFFER);
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return (0);
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}
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// Return the number of Unicode characters written.
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return (cchWC);
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}
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// UTF8ToUnicode
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// Maps a UTF-8 character string to its wide character string counterpart.
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// 02-06-96 JulieB Created.
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int UTF8ToUnicode(
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LPCSTR lpSrcStr,
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int cchSrc,
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LPWSTR lpDestStr,
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int cchDest)
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{
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int nTB = 0; // # trail bytes to follow
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int cchWC = 0; // # of Unicode code points generated
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LPCSTR pUTF8 = lpSrcStr;
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DWORD dwSurrogateChar; // Full surrogate char
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BOOL bSurrogatePair = FALSE; // Indicate we'r collecting a surrogate pair
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char UTF8;
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while ((cchSrc--) && ((cchDest == 0) || (cchWC < cchDest)))
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{
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// See if there are any trail bytes.
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if (BIT7(*pUTF8) == 0)
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{
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// Found ASCII.
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if (cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)*pUTF8;
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}
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bSurrogatePair = FALSE;
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cchWC++;
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}
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else if (BIT6(*pUTF8) == 0)
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{
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// Found a trail byte.
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// Note : Ignore the trail byte if there was no lead byte.
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if (nTB != 0)
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{
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// Decrement the trail byte counter.
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nTB--;
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if (bSurrogatePair)
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{
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dwSurrogateChar <<= 6;
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dwSurrogateChar |= LOWER_6_BIT(*pUTF8);
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if (nTB == 0)
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{
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if (cchDest)
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{
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if ((cchWC + 1) < cchDest)
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{
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lpDestStr[cchWC] = (WCHAR)
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(((dwSurrogateChar - 0x10000) >> 10) + HIGH_SURROGATE_START);
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lpDestStr[cchWC+1] = (WCHAR)
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((dwSurrogateChar - 0x10000)%0x400 + LOW_SURROGATE_START);
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}
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else
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{
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// Error : Buffer too small
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cchSrc++;
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break;
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}
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}
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cchWC += 2;
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bSurrogatePair = FALSE;
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}
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}
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else
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{
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// Make room for the trail byte and add the trail byte
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// value.
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if (cchDest)
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{
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lpDestStr[cchWC] <<= 6;
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lpDestStr[cchWC] |= LOWER_6_BIT(*pUTF8);
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}
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if (nTB == 0)
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{
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// End of sequence. Advance the output counter.
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cchWC++;
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}
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}
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}
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else
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{
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// error - not expecting a trail byte
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bSurrogatePair = FALSE;
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}
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}
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else
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{
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// Found a lead byte.
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if (nTB > 0)
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{
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// Error - previous sequence not finished.
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nTB = 0;
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bSurrogatePair = FALSE;
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cchWC++;
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}
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else
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{
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// Calculate the number of bytes to follow.
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// Look for the first 0 from left to right.
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UTF8 = *pUTF8;
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while (BIT7(UTF8) != 0)
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{
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UTF8 <<= 1;
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nTB++;
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}
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// If this is a surrogate unicode pair
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if (nTB == 4)
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{
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dwSurrogateChar = UTF8 >> nTB;
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bSurrogatePair = TRUE;
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}
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// Store the value from the first byte and decrement
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// the number of bytes to follow.
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if (cchDest)
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{
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lpDestStr[cchWC] = UTF8 >> nTB;
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}
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nTB--;
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}
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}
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pUTF8++;
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}
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// Make sure the destination buffer was large enough.
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if (cchDest && (cchSrc >= 0))
|
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{
|
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SetLastError(ERROR_INSUFFICIENT_BUFFER);
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return (0);
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}
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|
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// Return the number of Unicode characters written.
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|
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return (cchWC);
|
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}
|
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|
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|
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|
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|
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// UnicodeToUTF7
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|
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// Maps a Unicode character string to its UTF-7 string counterpart.
|
|
|
|
// 02-06-96 JulieB Created.
|
|
|
|
|
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int UnicodeToUTF7(
|
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LPCWSTR lpSrcStr,
|
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int cchSrc,
|
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LPSTR lpDestStr,
|
|
int cchDest)
|
|
{
|
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LPCWSTR lpWC = lpSrcStr;
|
|
BOOL fShift = FALSE;
|
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DWORD dwBit = 0; // 32-bit buffer
|
|
int iPos = 0; // 6-bit position in buffer
|
|
int cchU7 = 0; // # of UTF7 chars generated
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|
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while ((cchSrc--) && ((cchDest == 0) || (cchU7 < cchDest)))
|
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{
|
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if ((*lpWC > ASCII) || (fShiftChar[*lpWC]))
|
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{
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|
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// Need shift. Store 16 bits in buffer.
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|
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dwBit |= ((DWORD)*lpWC) << (16 - iPos);
|
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iPos += 16;
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|
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if (!fShift)
|
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{
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|
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// Not in shift state, so add "+".
|
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|
|
if (cchDest)
|
|
{
|
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lpDestStr[cchU7] = SHIFT_IN;
|
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}
|
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cchU7++;
|
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|
|
|
|
// Go into shift state.
|
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|
|
fShift = TRUE;
|
|
}
|
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|
|
|
|
// 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
|
|
DWORD dwSurrogateChar;
|
|
WCHAR wchHighSurrogate = 0;
|
|
BOOL bHandled;
|
|
|
|
|
|
while ((cchSrc--) && ((cchDest == 0) || (cchU8 < cchDest)))
|
|
{
|
|
bHandled = FALSE;
|
|
|
|
|
|
// Check if high surrogate is available
|
|
|
|
if ((*lpWC >= HIGH_SURROGATE_START) && (*lpWC <= HIGH_SURROGATE_END))
|
|
{
|
|
if (cchDest)
|
|
{
|
|
// Another high surrogate, then treat the 1st as normal
|
|
// Unicode character.
|
|
if (wchHighSurrogate)
|
|
{
|
|
if ((cchU8 + 2) < cchDest)
|
|
{
|
|
lpDestStr[cchU8++] = UTF8_1ST_OF_3 | HIGHER_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | MIDDLE_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | LOWER_6_BIT(wchHighSurrogate);
|
|
}
|
|
else
|
|
{
|
|
// not enough buffer
|
|
cchSrc++;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
cchU8 += 3;
|
|
}
|
|
wchHighSurrogate = *lpWC;
|
|
bHandled = TRUE;
|
|
}
|
|
|
|
if (!bHandled && wchHighSurrogate)
|
|
{
|
|
if ((*lpWC >= LOW_SURROGATE_START) && (*lpWC <= LOW_SURROGATE_END))
|
|
{
|
|
// wheee, valid surrogate pairs
|
|
|
|
if (cchDest)
|
|
{
|
|
if ((cchU8 + 3) < cchDest)
|
|
{
|
|
dwSurrogateChar = (((wchHighSurrogate-0xD800) << 10) + (*lpWC - 0xDC00) + 0x10000);
|
|
|
|
lpDestStr[cchU8++] = (UTF8_1ST_OF_4 |
|
|
(unsigned char)(dwSurrogateChar >> 18)); // 3 bits from 1st byte
|
|
|
|
lpDestStr[cchU8++] = (UTF8_TRAIL |
|
|
(unsigned char)((dwSurrogateChar >> 12) & 0x3f)); // 6 bits from 2nd byte
|
|
|
|
lpDestStr[cchU8++] = (UTF8_TRAIL |
|
|
(unsigned char)((dwSurrogateChar >> 6) & 0x3f)); // 6 bits from 3rd byte
|
|
|
|
lpDestStr[cchU8++] = (UTF8_TRAIL |
|
|
(unsigned char)(0x3f & dwSurrogateChar)); // 6 bits from 4th byte
|
|
}
|
|
else
|
|
{
|
|
// not enough buffer
|
|
cchSrc++;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// we already counted 3 previously (in high surrogate)
|
|
cchU8 += 1;
|
|
}
|
|
|
|
bHandled = TRUE;
|
|
}
|
|
else
|
|
{
|
|
// Bad Surrogate pair : ERROR
|
|
// Just process wchHighSurrogate , and the code below will
|
|
// process the current code point
|
|
if (cchDest)
|
|
{
|
|
if ((cchU8 + 2) < cchDest)
|
|
{
|
|
lpDestStr[cchU8++] = UTF8_1ST_OF_3 | HIGHER_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | MIDDLE_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | LOWER_6_BIT(wchHighSurrogate);
|
|
}
|
|
else
|
|
{
|
|
// not enough buffer
|
|
cchSrc++;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
wchHighSurrogate = 0;
|
|
}
|
|
|
|
if (!bHandled)
|
|
{
|
|
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 | HIGHER_6_BIT(*lpWC);
|
|
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++;
|
|
}
|
|
|
|
|
|
// If the last character was a high surrogate, then handle it as a normal
|
|
// unicode character.
|
|
|
|
if ((cchSrc < 0) && (wchHighSurrogate != 0))
|
|
{
|
|
if (cchDest)
|
|
{
|
|
if ((cchU8 + 2) < cchDest)
|
|
{
|
|
lpDestStr[cchU8++] = UTF8_1ST_OF_3 | HIGHER_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | MIDDLE_6_BIT(wchHighSurrogate);
|
|
lpDestStr[cchU8++] = UTF8_TRAIL | LOWER_6_BIT(wchHighSurrogate);
|
|
}
|
|
else
|
|
{
|
|
cchSrc++;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
// 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);
|
|
}
|