gecko/intl/uconv/ucvlatin/nsUnicodeToUTF7.cpp
2010-07-04 15:42:04 +03:00

331 lines
9.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsUnicodeToUTF7.h"
#include <string.h>
//----------------------------------------------------------------------
// Global functions and data [declaration]
#define ENC_DIRECT 0
#define ENC_BASE64 1
//----------------------------------------------------------------------
// Class nsBasicUTF7Encoder [implementation]
nsBasicUTF7Encoder::nsBasicUTF7Encoder(char aLastChar, char aEscChar)
: nsEncoderSupport(5)
{
mLastChar = aLastChar;
mEscChar = aEscChar;
Reset();
}
nsresult nsBasicUTF7Encoder::ShiftEncoding(PRInt32 aEncoding,
char * aDest,
PRInt32 * aDestLength)
{
if (aEncoding == mEncoding) {
*aDestLength = 0;
return NS_OK;
}
nsresult res = NS_OK;
char * dest = aDest;
char * destEnd = aDest + *aDestLength;
if (mEncStep != 0) {
if (dest >= destEnd) return NS_OK_UENC_MOREOUTPUT;
*(dest++)=ValueToChar(mEncBits);
mEncStep = 0;
mEncBits = 0;
}
if (dest >= destEnd) {
res = NS_OK_UENC_MOREOUTPUT;
} else {
switch (aEncoding) {
case 0:
*(dest++) = '-';
mEncStep = 0;
mEncBits = 0;
break;
case 1:
*(dest++) = mEscChar;
break;
}
mEncoding = aEncoding;
}
*aDestLength = dest - aDest;
return res;
}
nsresult nsBasicUTF7Encoder::EncodeDirect(
const PRUnichar * aSrc,
PRInt32 * aSrcLength,
char * aDest,
PRInt32 * aDestLength)
{
nsresult res = NS_OK;
const PRUnichar * src = aSrc;
const PRUnichar * srcEnd = aSrc + *aSrcLength;
char * dest = aDest;
char * destEnd = aDest + *aDestLength;
PRUnichar ch;
while (src < srcEnd) {
ch = *src;
// stop when we reach Unicode chars
if (!DirectEncodable(ch)) break;
if (ch == mEscChar) {
// special case for the escape char
if (destEnd - dest < 1) {
res = NS_OK_UENC_MOREOUTPUT;
break;
} else {
*dest++ = (char)ch;
*dest++ = (char)'-';
src++;
}
} else {
//classic direct encoding
if (dest >= destEnd) {
res = NS_OK_UENC_MOREOUTPUT;
break;
} else {
*dest++ = (char)ch;
src++;
}
}
}
*aSrcLength = src - aSrc;
*aDestLength = dest - aDest;
return res;
}
nsresult nsBasicUTF7Encoder::EncodeBase64(
const PRUnichar * aSrc,
PRInt32 * aSrcLength,
char * aDest,
PRInt32 * aDestLength)
{
nsresult res = NS_OK;
const PRUnichar * src = aSrc;
const PRUnichar * srcEnd = aSrc + *aSrcLength;
char * dest = aDest;
char * destEnd = aDest + *aDestLength;
PRUnichar ch;
PRUint32 value;
while (src < srcEnd) {
ch = *src;
// stop when we reach printable US-ASCII chars
if (DirectEncodable(ch)) break;
switch (mEncStep) {
case 0:
if (destEnd - dest < 2) {
res = NS_OK_UENC_MOREOUTPUT;
break;
}
value=ch>>10;
*(dest++)=ValueToChar(value);
value=(ch>>4)&0x3f;
*(dest++)=ValueToChar(value);
mEncBits=(ch&0x0f)<<2;
break;
case 1:
if (destEnd - dest < 3) {
res = NS_OK_UENC_MOREOUTPUT;
break;
}
value=mEncBits+(ch>>14);
*(dest++)=ValueToChar(value);
value=(ch>>8)&0x3f;
*(dest++)=ValueToChar(value);
value=(ch>>2)&0x3f;
*(dest++)=ValueToChar(value);
mEncBits=(ch&0x03)<<4;
break;
case 2:
if (destEnd - dest < 3) {
res = NS_OK_UENC_MOREOUTPUT;
break;
}
value=mEncBits+(ch>>12);
*(dest++)=ValueToChar(value);
value=(ch>>6)&0x3f;
*(dest++)=ValueToChar(value);
value=ch&0x3f;
*(dest++)=ValueToChar(value);
mEncBits=0;
break;
}
if (res != NS_OK) break;
src++;
(++mEncStep)%=3;
}
*aSrcLength = src - aSrc;
*aDestLength = dest - aDest;
return res;
}
char nsBasicUTF7Encoder::ValueToChar(PRUint32 aValue) {
if (aValue < 26)
return (char)('A'+aValue);
else if (aValue < 26 + 26)
return (char)('a' + aValue - 26);
else if (aValue < 26 + 26 + 10)
return (char)('0' + aValue - 26 - 26);
else if (aValue == 26 + 26 + 10)
return '+';
else if (aValue == 26 + 26 + 10 + 1)
return mLastChar;
else
return -1;
}
PRBool nsBasicUTF7Encoder::DirectEncodable(PRUnichar aChar) {
// spec says: printable US-ASCII chars
if ((aChar >= 0x20) && (aChar <= 0x7e)) return PR_TRUE;
else return PR_FALSE;
}
//----------------------------------------------------------------------
// Subclassing of nsEncoderSupport class [implementation]
NS_IMETHODIMP nsBasicUTF7Encoder::ConvertNoBuffNoErr(
const PRUnichar * aSrc,
PRInt32 * aSrcLength,
char * aDest,
PRInt32 * aDestLength)
{
nsresult res = NS_OK;
const PRUnichar * src = aSrc;
const PRUnichar * srcEnd = aSrc + *aSrcLength;
char * dest = aDest;
char * destEnd = aDest + *aDestLength;
PRInt32 bcr,bcw;
PRUnichar ch;
PRInt32 enc;
while (src < srcEnd) {
// find the encoding for the next char
ch = *src;
if (DirectEncodable(ch))
enc = ENC_DIRECT;
else
enc = ENC_BASE64;
// if necessary, shift into the required encoding
bcw = destEnd - dest;
res = ShiftEncoding(enc, dest, &bcw);
dest += bcw;
if (res != NS_OK) break;
// now encode (as much as you can)
bcr = srcEnd - src;
bcw = destEnd - dest;
if (enc == ENC_DIRECT)
res = EncodeDirect(src, &bcr, dest, &bcw);
else
res = EncodeBase64(src, &bcr, dest, &bcw);
src += bcr;
dest += bcw;
if (res != NS_OK) break;
}
*aSrcLength = src - aSrc;
*aDestLength = dest - aDest;
return res;
}
NS_IMETHODIMP nsBasicUTF7Encoder::FinishNoBuff(char * aDest,
PRInt32 * aDestLength)
{
return ShiftEncoding(ENC_DIRECT, aDest, aDestLength);
}
NS_IMETHODIMP nsBasicUTF7Encoder::Reset()
{
mEncoding = ENC_DIRECT;
mEncBits = 0;
mEncStep = 0;
return nsEncoderSupport::Reset();
}
//----------------------------------------------------------------------
// Class nsUnicodeToUTF7 [implementation]
nsUnicodeToUTF7::nsUnicodeToUTF7()
: nsBasicUTF7Encoder('/', '+')
{
}
PRBool nsUnicodeToUTF7::DirectEncodable(PRUnichar aChar) {
if ((aChar >= 'A') && (aChar <= 'Z')) return PR_TRUE;
else if ((aChar >= 'a') && (aChar <= 'z')) return PR_TRUE;
else if ((aChar >= '0') && (aChar <= '9')) return PR_TRUE;
else if ((aChar >= 39) && (aChar <= 41)) return PR_TRUE;
else if ((aChar >= 44) && (aChar <= 47)) return PR_TRUE;
else if (aChar == 58) return PR_TRUE;
else if (aChar == 63) return PR_TRUE;
else if (aChar == ' ') return PR_TRUE;
else if (aChar == 9) return PR_TRUE;
else if (aChar == 13) return PR_TRUE;
else if (aChar == 10) return PR_TRUE;
else if (aChar == 60) return PR_TRUE; // '<'
else if (aChar == 33) return PR_TRUE; // '!'
else if (aChar == 34) return PR_TRUE; // '"'
else if (aChar == 62) return PR_TRUE; // '>'
else if (aChar == 61) return PR_TRUE; // '='
else if (aChar == 59) return PR_TRUE; // ';'
else if (aChar == 91) return PR_TRUE; // '['
else if (aChar == 93) return PR_TRUE; // ']'
else return PR_FALSE;
}