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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#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) {
mLastChar = aLastChar;
mEscChar = aEscChar;
Reset();
}
nsresult nsBasicUTF7Encoder::ShiftEncoding(int32_t aEncoding, char* aDest,
int32_t* 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 char16_t* aSrc,
int32_t* aSrcLength, char* aDest,
int32_t* aDestLength) {
nsresult res = NS_OK;
const char16_t* src = aSrc;
const char16_t* srcEnd = aSrc + *aSrcLength;
char* dest = aDest;
char* destEnd = aDest + *aDestLength;
char16_t 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 char16_t* aSrc,
int32_t* aSrcLength, char* aDest,
int32_t* aDestLength) {
nsresult res = NS_OK;
const char16_t* src = aSrc;
const char16_t* srcEnd = aSrc + *aSrcLength;
char* dest = aDest;
char* destEnd = aDest + *aDestLength;
char16_t ch;
uint32_t 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(uint32_t 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;
}
bool nsBasicUTF7Encoder::DirectEncodable(char16_t aChar) {
// spec says: printable US-ASCII chars
if ((aChar >= 0x20) && (aChar <= 0x7e))
return true;
else
return false;
}
//----------------------------------------------------------------------
// Subclassing of nsEncoderSupport class [implementation]
NS_IMETHODIMP nsBasicUTF7Encoder::ConvertNoBuffNoErr(const char16_t* aSrc,
int32_t* aSrcLength,
char* aDest,
int32_t* aDestLength) {
nsresult res = NS_OK;
const char16_t* src = aSrc;
const char16_t* srcEnd = aSrc + *aSrcLength;
char* dest = aDest;
char* destEnd = aDest + *aDestLength;
int32_t bcr, bcw;
char16_t ch;
int32_t 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,
int32_t* aDestLength) {
return ShiftEncoding(ENC_DIRECT, aDest, aDestLength);
}
NS_IMETHODIMP nsBasicUTF7Encoder::Reset() {
mEncoding = ENC_DIRECT;
mEncBits = 0;
mEncStep = 0;
return NS_OK;
}
//----------------------------------------------------------------------
// Class nsUnicodeToUTF7 [implementation]
nsUnicodeToUTF7::nsUnicodeToUTF7() : nsBasicUTF7Encoder('/', '+') {}
bool nsUnicodeToUTF7::DirectEncodable(char16_t aChar) {
if ((aChar >= 'A') && (aChar <= 'Z'))
return true;
else if ((aChar >= 'a') && (aChar <= 'z'))
return true;
else if ((aChar >= '0') && (aChar <= '9'))
return true;
else if ((aChar >= 39) && (aChar <= 41))
return true;
else if ((aChar >= 44) && (aChar <= 47))
return true;
else if (aChar == 58)
return true;
else if (aChar == 63)
return true;
else if (aChar == ' ')
return true;
else if (aChar == 9)
return true;
else if (aChar == 13)
return true;
else if (aChar == 10)
return true;
else if (aChar == 60)
return true; // '<'
else if (aChar == 33)
return true; // '!'
else if (aChar == 34)
return true; // '"'
else if (aChar == 62)
return true; // '>'
else if (aChar == 61)
return true; // '='
else if (aChar == 59)
return true; // ';'
else if (aChar == 91)
return true; // '['
else if (aChar == 93)
return true; // ']'
else
return false;
}