kmime_header_parsing.cpp

/*
    kmime_header_parsing.cpp
 
    This file is part of KMime, the KDE internet mail/usenet news message library.
    Copyright (c) 2001-2002 Marc Mutz <mutz@kde.org>
 
    KMime is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.
 
    KMime is distributed in the hope that it will be useful, but
    WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    General Public License for more details.
 
    You should have received a copy of the GNU General Public License
    along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
    In addition, as a special exception, the copyright holders give
    permission to link the code of this library with any edition of
    the TQt library by Trolltech AS, Norway (or with modified versions
    of TQt that use the same license as TQt), and distribute linked
    combinations including the two.  You must obey the GNU General
    Public License in all respects for all of the code used other than
    TQt.  If you modify this file, you may extend this exception to
    your version of the file, but you are not obligated to do so.  If
    you do not wish to do so, delete this exception statement from
    your version.
*/
 
#include <config.h>
#include "kmime_header_parsing.h"
 
#include "kmime_codecs.h"
#include "kmime_util.h"
#include "kmime_warning.h"
 
#include <tdeglobal.h>
#include <kcharsets.h>
 
#include <tqtextcodec.h>
#include <tqmap.h>
#include <tqcstring.h>
#include <tqstringlist.h>
 
#include <ctype.h> // for isdigit
#include <cassert>
 
using namespace KMime;
using namespace KMime::Types;
 
namespace KMime {
 
namespace Types {
 
  TQString AddrSpec::asString() const {
    bool needsQuotes = false;
    TQString result;
    result.reserve( localPart.length() + domain.length() + 1 );
    for ( unsigned int i = 0 ; i < localPart.length() ; ++i ) {
      const char ch = localPart[i].latin1();
      if ( ch == '.' || isAText( ch ) )
    result += ch;
      else {
    needsQuotes = true;
    if ( ch == '\\' || ch == '"' )
      result += '\\';
    result += ch;
      }
    }
    if ( needsQuotes )
      return '"' + result + "\"@" + domain;
    else
      return result + '@' + domain;
  }
 
}
 
namespace HeaderParsing {
 
// parse the encoded-word (scursor points to after the initial '=')
bool parseEncodedWord( const char* & scursor, const char * const send,
               TQString & result, TQCString & language ) {
 
  // make sure the caller already did a bit of the work.
  assert( *(scursor-1) == '=' );
 
  //
  // STEP 1:
  // scan for the charset/language portion of the encoded-word
  //
 
  char ch = *scursor++;
 
  if ( ch != '?' ) {
    kdDebug() << "first" << endl;
    KMIME_WARN_PREMATURE_END_OF(EncodedWord);
    return false;
  }
 
  // remember start of charset (ie. just after the initial "=?") and
  // language (just after the first '*') fields:
  const char * charsetStart = scursor;
  const char * languageStart = 0;
 
  // find delimiting '?' (and the '*' separating charset and language
  // tags, if any):
  for ( ; scursor != send ; scursor++ )
    if ( *scursor == '?')
      break;
    else if ( *scursor == '*' && !languageStart )
      languageStart = scursor + 1;
 
  // not found? can't be an encoded-word!
  if ( scursor == send || *scursor != '?' ) {
    kdDebug() << "second" << endl;
    KMIME_WARN_PREMATURE_END_OF(EncodedWord);
    return false;
  }
 
  // extract the language information, if any (if languageStart is 0,
  // language will be null, too):
  TQCString maybeLanguage( languageStart, scursor - languageStart + 1 /*for NUL*/);
  // extract charset information (keep in mind: the size given to the
  // ctor is one off due to the \0 terminator):
  TQCString maybeCharset( charsetStart, ( languageStart ? languageStart : scursor + 1 ) - charsetStart );
 
  //
  // STEP 2:
  // scan for the encoding portion of the encoded-word
  //
 
 
  // remember start of encoding (just _after_ the second '?'):
  scursor++;
  const char * encodingStart = scursor;
 
  // find next '?' (ending the encoding tag):
  for ( ; scursor != send ; scursor++ )
    if ( *scursor == '?' ) break;
 
  // not found? Can't be an encoded-word!
  if ( scursor == send || *scursor != '?' ) {
    kdDebug() << "third" << endl;
    KMIME_WARN_PREMATURE_END_OF(EncodedWord);
    return false;
  }
 
  // extract the encoding information:
  TQCString maybeEncoding( encodingStart, scursor - encodingStart + 1 );
 
 
  kdDebug() << "parseEncodedWord: found charset == \"" << maybeCharset
        << "\"; language == \"" << maybeLanguage
        << "\"; encoding == \"" << maybeEncoding << "\"" << endl;
 
  //
  // STEP 3:
  // scan for encoded-text portion of encoded-word
  //
 
 
  // remember start of encoded-text (just after the third '?'):
  scursor++;
  const char * encodedTextStart = scursor;
 
  // find next '?' (ending the encoded-text):
  for ( ; scursor != send ; scursor++ )
    if ( *scursor == '?' ) break;
 
  // not found? Can't be an encoded-word!
  // ### maybe evaluate it nonetheless if the rest is OK?
  if ( scursor == send || *scursor != '?' ) {
    kdDebug() << "fourth" << endl;
    KMIME_WARN_PREMATURE_END_OF(EncodedWord);
    return false;
  }
  scursor++;
  // check for trailing '=':
  if ( scursor == send || *scursor != '=' ) {
    kdDebug() << "fifth" << endl;
    KMIME_WARN_PREMATURE_END_OF(EncodedWord);
    return false;
  }
  scursor++;
 
  // set end sentinel for encoded-text:
  const char * const encodedTextEnd = scursor - 2;
 
  //
  // STEP 4:
  // setup decoders for the transfer encoding and the charset
  //
 
 
  // try if there's a codec for the encoding found:
  Codec * codec = Codec::codecForName( maybeEncoding );
  if ( !codec ) {
    KMIME_WARN_UNKNOWN(Encoding,maybeEncoding);
    return false;
  }
 
  // get an instance of a corresponding decoder:
  Decoder * dec = codec->makeDecoder();
  assert( dec );
 
  // try if there's a (text)codec for the charset found:
  bool matchOK = false;
  TQTextCodec
    *textCodec = TDEGlobal::charsets()->codecForName( maybeCharset, matchOK );
 
  if ( !matchOK || !textCodec ) {
    KMIME_WARN_UNKNOWN(Charset,maybeCharset);
    delete dec;
    return false;
  };
 
  kdDebug() << "mimeName(): \"" << textCodec->mimeName() << "\"" << endl;
 
  // allocate a temporary buffer to store the 8bit text:
  int encodedTextLength = encodedTextEnd - encodedTextStart;
  TQByteArray buffer( codec->maxDecodedSizeFor( encodedTextLength ) );
  TQByteArray::Iterator bit = buffer.begin();
  TQByteArray::ConstIterator bend = buffer.end();
 
  //
  // STEP 5:
  // do the actual decoding
  //
 
  if ( !dec->decode( encodedTextStart, encodedTextEnd, bit, bend ) )
    KMIME_WARN << codec->name() << " codec lies about it's maxDecodedSizeFor( "
           << encodedTextLength << " )\nresult may be truncated" << endl;
 
  result = textCodec->toUnicode( buffer.begin(), bit - buffer.begin() );
 
  kdDebug() << "result now: \"" << result << "\"" << endl;
  // cleanup:
  delete dec;
  language = maybeLanguage;
 
  return true;
}
 
static inline void eatWhiteSpace( const char* & scursor, const char * const send ) {
  while ( scursor != send
      && ( *scursor == ' ' || *scursor == '\n' ||
           *scursor == '\t' || *scursor == '\r' ) )
    scursor++;
}
 
bool parseAtom( const char * & scursor, const char * const send,
        TQString & result, bool allow8Bit )
{
  TQPair<const char*,int> maybeResult;
 
  if ( parseAtom( scursor, send, maybeResult, allow8Bit ) ) {
    result += TQString::fromLatin1( maybeResult.first, maybeResult.second );
    return true;
  }
 
  return false;
}
 
bool parseAtom( const char * & scursor, const char * const send,
        TQPair<const char*,int> & result, bool allow8Bit ) {
  bool success = false;
  const char * start = scursor;
 
  while ( scursor != send ) {
    signed char ch = *scursor++;
    if ( ch > 0 && isAText(ch) ) {
      // AText: OK
      success = true;
    } else if ( allow8Bit && ch < 0 ) {
      // 8bit char: not OK, but be tolerant.
      KMIME_WARN_8BIT(ch);
      success = true;
    } else {
      // CTL or special - marking the end of the atom:
      // re-set sursor to point to the offending
      // char and return:
      scursor--;
      break;
    }
  }
  result.first = start;
  result.second = scursor - start;
  return success;
}
 
bool parseToken( const char * & scursor, const char * const send,
         TQString & result, bool allow8Bit )
{
  TQPair<const char*,int> maybeResult;
 
  if ( parseToken( scursor, send, maybeResult, allow8Bit ) ) {
    result += TQString::fromLatin1( maybeResult.first, maybeResult.second );
    return true;
  }
 
  return false;
}
 
bool parseToken( const char * & scursor, const char * const send,
         TQPair<const char*,int> & result, bool allow8Bit )
{
  bool success = false;
  const char * start = scursor;
 
  while ( scursor != send ) {
    signed char ch = *scursor++;
    if ( ch > 0 && isTText(ch) ) {
      // TText: OK
      success = true;
    } else if ( allow8Bit && ch < 0 ) {
      // 8bit char: not OK, but be tolerant.
      KMIME_WARN_8BIT(ch);
      success = true;
    } else {
      // CTL or tspecial - marking the end of the atom:
      // re-set sursor to point to the offending
      // char and return:
      scursor--;
      break;
    }
  }
  result.first = start;
  result.second = scursor - start;
  return success;
}
 
#define READ_ch_OR_FAIL if ( scursor == send ) { \
                          KMIME_WARN_PREMATURE_END_OF(GenericQuotedString); \
                          return false; \
                        } else { \
                          ch = *scursor++; \
                }
 
// known issues:
//
// - doesn't handle quoted CRLF
 
bool parseGenericQuotedString( const char* & scursor, const char * const send,
                   TQString & result, bool isCRLF,
                   const char openChar, const char closeChar )
{
  char ch;
  // We are in a quoted-string or domain-literal or comment and the
  // cursor points to the first char after the openChar.
  // We will apply unfolding and quoted-pair removal.
  // We return when we either encounter the end or unescaped openChar
  // or closeChar.
 
  assert( *(scursor-1) == openChar || *(scursor-1) == closeChar );
 
  while ( scursor != send ) {
    ch = *scursor++;
 
    if ( ch == closeChar || ch == openChar ) {
      // end of quoted-string or another opening char:
      // let caller decide what to do.
      return true;
    }
 
    switch( ch ) {
    case '\\':      // quoted-pair
      // misses "\" CRLF LWSP-char handling, see rfc822, 3.4.5
      READ_ch_OR_FAIL;
      KMIME_WARN_IF_8BIT(ch);
      result += TQChar(ch);
      break;
    case '\r':
      // ###
      // The case of lonely '\r' is easy to solve, as they're
      // not part of Unix Line-ending conventions.
      // But I see a problem if we are given Unix-native
      // line-ending-mails, where we cannot determine anymore
      // whether a given '\n' was part of a CRLF or was occurring
      // on it's own.
      READ_ch_OR_FAIL;
      if ( ch != '\n' ) {
    // CR on it's own...
    KMIME_WARN_LONE(CR);
    result += TQChar('\r');
    scursor--; // points to after the '\r' again
      } else {
    // CRLF encountered.
    // lookahead: check for folding
    READ_ch_OR_FAIL;
    if ( ch == ' ' || ch == '\t' ) {
      // correct folding;
      // position cursor behind the CRLF WSP (unfolding)
      // and add the WSP to the result
      result += TQChar(ch);
    } else {
      // this is the "shouldn't happen"-case. There is a CRLF
      // inside a quoted-string without it being part of FWS.
      // We take it verbatim.
      KMIME_WARN_NON_FOLDING(CRLF);
      result += "\r\n";
      // the cursor is decremented again, so's we need not
      // duplicate the whole switch here. "ch" could've been
      // everything (incl. openChar or closeChar).
      scursor--;
    }
      }
      break;
    case '\n':
      // Note: CRLF has been handled above already!
      // ### LF needs special treatment, depending on whether isCRLF
      // is true (we can be sure a lonely '\n' was meant this way) or
      // false ('\n' alone could have meant LF or CRLF in the original
      // message. This parser assumes CRLF iff the LF is followed by
      // either WSP (folding) or NULL (premature end of quoted-string;
      // Should be fixed, since NULL is allowed as per rfc822).
      READ_ch_OR_FAIL;
      if ( !isCRLF && ( ch == ' ' || ch == '\t' ) ) {
    // folding
    // correct folding
    result += TQChar(ch);
      } else {
    // non-folding
    KMIME_WARN_LONE(LF);
    result += TQChar('\n');
    // pos is decremented, so's we need not duplicate the whole
    // switch here. ch could've been everything (incl. <">, "\").
    scursor--;
      }
      break;
    default:
      KMIME_WARN_IF_8BIT(ch);
      result += TQChar(ch);
    }
  }
 
  return false;
}
 
// known issues:
//
// - doesn't handle encoded-word inside comments.
 
bool parseComment( const char* & scursor, const char * const send,
           TQString & result, bool isCRLF, bool reallySave )
{
  int commentNestingDepth = 1;
  const char * afterLastClosingParenPos = 0;
  TQString maybeCmnt;
  const char * oldscursor = scursor;
 
  assert( *(scursor-1) == '(' );
 
  while ( commentNestingDepth ) {
    TQString cmntPart;
    if ( parseGenericQuotedString( scursor, send, cmntPart, isCRLF, '(', ')' ) ) {
      assert( *(scursor-1) == ')' || *(scursor-1) == '(' );
      // see the kdoc for above function for the possible conditions
      // we have to check:
      switch ( *(scursor-1) ) {
      case ')':
    if ( reallySave ) {
      // add the chunk that's now surely inside the comment.
      result += maybeCmnt;
      result += cmntPart;
      if ( commentNestingDepth > 1 ) // don't add the outermost ')'...
        result += TQChar(')');
      maybeCmnt = TQString();
    }
    afterLastClosingParenPos = scursor;
    --commentNestingDepth;
    break;
      case '(':
    if ( reallySave ) {
      // don't add to "result" yet, because we might find that we
      // are already outside the (broken) comment...
      maybeCmnt += cmntPart;
      maybeCmnt += TQChar('(');
    }
    ++commentNestingDepth;
    break;
      default: assert( 0 );
      } // switch
    } else {
      // !parseGenericQuotedString, ie. premature end
      if ( afterLastClosingParenPos )
    scursor = afterLastClosingParenPos;
      else
    scursor = oldscursor;
      return false;
    }
  } // while
 
  return true;
}
 
 
// known issues: none.
 
bool parsePhrase( const char* & scursor, const char * const send,
          TQString & result, bool isCRLF )
{
  enum { None, Phrase, Atom, EncodedWord, QuotedString } found = None;
  TQString tmp;
  TQCString lang;
  const char * successfullyParsed = 0;
  // only used by the encoded-word branch
  const char * oldscursor;
  // used to suppress whitespace between adjacent encoded-words
  // (rfc2047, 6.2):
  bool lastWasEncodedWord = false;
 
  while ( scursor != send ) {
    char ch = *scursor++;
    switch ( ch ) {
    case '.': // broken, but allow for intorop's sake
      if ( found == None ) {
    --scursor;
    return false;
      } else {
    if ( scursor != send && ( *scursor == ' ' || *scursor == '\t' ) )
      result += ". ";
    else
      result += '.';
    successfullyParsed = scursor;
      }
      break;
    case '"': // quoted-string
      tmp = TQString();
      if ( parseGenericQuotedString( scursor, send, tmp, isCRLF, '"', '"' ) ) {
    successfullyParsed = scursor;
    assert( *(scursor-1) == '"' );
    switch ( found ) {
    case None:
      found = QuotedString;
      break;
    case Phrase:
    case Atom:
    case EncodedWord:
    case QuotedString:
      found = Phrase;
      result += TQChar(' '); // rfc822, 3.4.4
      break;
    default:
      assert( 0 );
    }
    lastWasEncodedWord = false;
    result += tmp;
      } else {
    // premature end of quoted string.
    // What to do? Return leading '"' as special? Return as quoted-string?
    // We do the latter if we already found something, else signal failure.
    if ( found == None ) {
      return false;
    } else {
      result += TQChar(' '); // rfc822, 3.4.4
      result += tmp;
      return true;
    }
      }
      break;
    case '(': // comment
      // parse it, but ignore content:
      tmp = TQString();
      if ( parseComment( scursor, send, tmp, isCRLF,
             false /*don't bother with the content*/ ) ) {
    successfullyParsed = scursor;
    lastWasEncodedWord = false; // strictly interpreting rfc2047, 6.2
      } else {
    if ( found == None )
      return false;
    else {
      scursor = successfullyParsed;
      return true;
    }
      }
      break;
    case '=': // encoded-word
      tmp = TQString();
      oldscursor = scursor;
      lang = 0;
      if ( parseEncodedWord( scursor, send, tmp, lang ) ) {
    successfullyParsed = scursor;
    switch ( found ) {
    case None:
      found = EncodedWord;
      break;
    case Phrase:
    case EncodedWord:
    case Atom:
    case QuotedString:
      if ( !lastWasEncodedWord )
        result += TQChar(' '); // rfc822, 3.4.4
      found = Phrase;
      break;
    default: assert( 0 );
    }
    lastWasEncodedWord = true;
    result += tmp;
    break;
      } else
    // parse as atom:
    scursor = oldscursor;
      // fall though...
 
    default: //atom
      tmp = TQString();
      scursor--;
      if ( parseAtom( scursor, send, tmp, true /* allow 8bit */ ) ) {
    successfullyParsed = scursor;
    switch ( found ) {
    case None:
      found = Atom;
      break;
    case Phrase:
    case Atom:
    case EncodedWord:
    case QuotedString:
      found = Phrase;
      result += TQChar(' '); // rfc822, 3.4.4
      break;
    default:
      assert( 0 );
    }
    lastWasEncodedWord = false;
    result += tmp;
      } else {
    if ( found == None )
      return false;
    else {
      scursor = successfullyParsed;
      return true;
    }
      }
    }
    eatWhiteSpace( scursor, send );
  }
 
  return ( found != None );
}
 
 
bool parseDotAtom( const char* & scursor, const char * const send,
           TQString & result, bool isCRLF )
{
  // always points to just after the last atom parsed:
  const char * successfullyParsed;
 
  TQString tmp;
  if ( !parseAtom( scursor, send, tmp, false /* no 8bit */ ) )
    return false;
  result += tmp;
  successfullyParsed = scursor;
 
  while ( scursor != send ) {
    eatCFWS( scursor, send, isCRLF );
 
    // end of header or no '.' -> return
    if ( scursor == send || *scursor != '.' ) return true;
    scursor++; // eat '.'
 
    eatCFWS( scursor, send, isCRLF );
 
    if ( scursor == send || !isAText( *scursor ) ) {
      // end of header or no AText, but this time following a '.'!:
      // reset cursor to just after last successfully parsed char and
      // return:
      scursor = successfullyParsed;
      return true;
    }
 
    // try to parse the next atom:
    TQString maybeAtom;
    if ( !parseAtom( scursor, send, maybeAtom, false /*no 8bit*/ ) ) {
      scursor = successfullyParsed;
      return true;
    }
 
    result += TQChar('.');
    result += maybeAtom;
    successfullyParsed = scursor;
  }
 
  scursor = successfullyParsed;
  return true;
}
 
 
void eatCFWS( const char* & scursor, const char * const send, bool isCRLF ) {
  TQString dummy;
 
  while ( scursor != send ) {
    const char * oldscursor = scursor;
 
    char ch = *scursor++;
 
    switch( ch ) {
    case ' ':
    case '\t': // whitespace
    case '\r':
    case '\n': // folding
      continue;
 
    case '(': // comment
      if ( parseComment( scursor, send, dummy, isCRLF, false /*don't save*/ ) )
    continue;
      scursor = oldscursor;
      return;
 
    default:
      scursor = oldscursor;
      return;
    }
 
  }
}
 
bool parseDomain( const char* & scursor, const char * const send,
          TQString & result, bool isCRLF ) {
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // domain := dot-atom / domain-literal / atom *("." atom)
  //
  // equivalent to:
  // domain = dot-atom / domain-literal,
  // since parseDotAtom does allow CFWS between atoms and dots
 
  if ( *scursor == '[' ) {
    // domain-literal:
    TQString maybeDomainLiteral;
    // eat '[':
    scursor++;
    while ( parseGenericQuotedString( scursor, send, maybeDomainLiteral,
                      isCRLF, '[', ']' ) ) {
      if ( scursor == send ) {
    // end of header: check for closing ']':
    if ( *(scursor-1) == ']' ) {
      // OK, last char was ']':
      result = maybeDomainLiteral;
      return true;
    } else {
      // not OK, domain-literal wasn't closed:
      return false;
    }
      }
      // we hit openChar in parseGenericQuotedString.
      // include it in maybeDomainLiteral and keep on parsing:
      if ( *(scursor-1) == '[' ) {
    maybeDomainLiteral += TQChar('[');
    continue;
      }
      // OK, real end of domain-literal:
      result = maybeDomainLiteral;
      return true;
    }
  } else {
    // dot-atom:
    TQString maybeDotAtom;
    if ( parseDotAtom( scursor, send, maybeDotAtom, isCRLF ) ) {
      result = maybeDotAtom;
      return true;
    }
  }
  return false;
}
 
bool parseObsRoute( const char* & scursor, const char* const send,
            TQStringList & result, bool isCRLF, bool save ) {
  while ( scursor != send ) {
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
 
    // empty entry:
    if ( *scursor == ',' ) {
      scursor++;
      if ( save ) result.append( TQString() );
      continue;
    }
 
    // empty entry ending the list:
    if ( *scursor == ':' ) {
      scursor++;
      if ( save ) result.append( TQString() );
      return true;
    }
 
    // each non-empty entry must begin with '@':
    if ( *scursor != '@' )
      return false;
    else
      scursor++;
 
    TQString maybeDomain;
    if ( !parseDomain( scursor, send, maybeDomain, isCRLF ) ) return false;
    if ( save ) result.append( maybeDomain );
 
    // eat the following (optional) comma:
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
    if ( *scursor == ':' ) { scursor++; return true; }
    if ( *scursor == ',' ) scursor++;
 
  }
 
  return false;
}
 
bool parseAddrSpec( const char* & scursor, const char * const send,
            AddrSpec & result, bool isCRLF ) {
  //
  // STEP 1:
  // local-part := dot-atom / quoted-string / word *("." word)
  //
  // this is equivalent to:
  // local-part := word *("." word)
 
  TQString maybeLocalPart;
  TQString tmp;
 
  while ( scursor != send ) {
    // first, eat any whitespace
    eatCFWS( scursor, send, isCRLF );
 
    char ch = *scursor++;
    switch ( ch ) {
    case '.': // dot
      maybeLocalPart += TQChar('.');
      break;
 
    case '@':
      goto SAW_AT_SIGN;
      break;
 
    case '"': // quoted-string
      tmp = TQString();
      if ( parseGenericQuotedString( scursor, send, tmp, isCRLF, '"', '"' ) )
    maybeLocalPart += tmp;
      else
    return false;
      break;
 
    default: // atom
      scursor--; // re-set scursor to point to ch again
      tmp = TQString();
      if ( parseAtom( scursor, send, tmp, false /* no 8bit */ ) )
    maybeLocalPart += tmp;
      else
    return false; // parseAtom can only fail if the first char is non-atext.
      break;
    }
  }
 
  return false;
 
 
  //
  // STEP 2:
  // domain
  //
 
SAW_AT_SIGN:
 
  assert( *(scursor-1) == '@' );
 
  TQString maybeDomain;
  if ( !parseDomain( scursor, send, maybeDomain, isCRLF ) )
    return false;
 
  result.localPart = maybeLocalPart;
  result.domain = maybeDomain;
 
  return true;
}
 
 
bool parseAngleAddr( const char* & scursor, const char * const send,
             AddrSpec & result, bool isCRLF ) {
  // first, we need an opening angle bracket:
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send || *scursor != '<' ) return false;
  scursor++; // eat '<'
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  if ( *scursor == '@' || *scursor == ',' ) {
    // obs-route: parse, but ignore:
    KMIME_WARN << "obsolete source route found! ignoring." << endl;
    TQStringList dummy;
    if ( !parseObsRoute( scursor, send, dummy,
             isCRLF, false /* don't save */ ) )
      return false;
    // angle-addr isn't complete until after the '>':
    if ( scursor == send ) return false;
  }
 
  // parse addr-spec:
  AddrSpec maybeAddrSpec;
  if ( !parseAddrSpec( scursor, send, maybeAddrSpec, isCRLF ) ) return false;
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send || *scursor != '>' ) return false;
  scursor++;
 
  result = maybeAddrSpec;
  return true;
 
}
 
bool parseMailbox( const char* & scursor, const char * const send,
           Mailbox & result, bool isCRLF ) {
 
  // rfc:
  // mailbox := addr-spec / ([ display-name ] angle-addr)
  // us:
  // mailbox := addr-spec / ([ display-name ] angle-addr)
  //                      / (angle-addr "(" display-name ")")
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  AddrSpec maybeAddrSpec;
 
  // first, try if it's a vanilla addr-spec:
  const char * oldscursor = scursor;
  if ( parseAddrSpec( scursor, send, maybeAddrSpec, isCRLF ) ) {
    result.displayName = TQString();
    result.addrSpec = maybeAddrSpec;
    return true;
  }
  scursor = oldscursor;
 
  // second, see if there's a display-name:
  TQString maybeDisplayName;
  if ( !parsePhrase( scursor, send, maybeDisplayName, isCRLF ) ) {
    // failed: reset cursor, note absent display-name
    maybeDisplayName = TQString();
    scursor = oldscursor;
  } else {
    // succeeded: eat CFWS
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
  }
 
  // third, parse the angle-addr:
  if ( !parseAngleAddr( scursor, send, maybeAddrSpec, isCRLF ) )
    return false;
 
  if ( maybeDisplayName.isNull() ) {
    // check for the obsolete form of display-name (as comment):
    eatWhiteSpace( scursor, send );
    if ( scursor != send && *scursor == '(' ) {
      scursor++;
      if ( !parseComment( scursor, send, maybeDisplayName, isCRLF, true /*keep*/ ) )
    return false;
    }
  }
 
  result.displayName = maybeDisplayName;
  result.addrSpec = maybeAddrSpec;
  return true;
}
 
bool parseGroup( const char* & scursor, const char * const send,
         Address & result, bool isCRLF ) {
  // group         := display-name ":" [ mailbox-list / CFWS ] ";" [CFWS]
  //
  // equivalent to:
  // group   := display-name ":" [ obs-mbox-list ] ";"
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // get display-name:
  TQString maybeDisplayName;
  if ( !parsePhrase( scursor, send, maybeDisplayName, isCRLF ) )
    return false;
 
  // get ":":
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send || *scursor != ':' ) return false;
 
  result.displayName = maybeDisplayName;
 
  // get obs-mbox-list (may contain empty entries):
  scursor++;
  while ( scursor != send ) {
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
 
    // empty entry:
    if ( *scursor == ',' ) { scursor++; continue; }
 
    // empty entry ending the list:
    if ( *scursor == ';' ) { scursor++; return true; }
 
    Mailbox maybeMailbox;
    if ( !parseMailbox( scursor, send, maybeMailbox, isCRLF ) )
      return false;
    result.mailboxList.append( maybeMailbox );
 
    eatCFWS( scursor, send, isCRLF );
    // premature end:
    if ( scursor == send ) return false;
    // regular end of the list:
    if ( *scursor == ';' ) { scursor++; return true; }
    // eat regular list entry separator:
    if ( *scursor == ',' ) scursor++;
  }
  return false;
}
 
 
bool parseAddress( const char* & scursor, const char * const send,
           Address & result, bool isCRLF ) {
  // address       := mailbox / group
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // first try if it's a single mailbox:
  Mailbox maybeMailbox;
  const char * oldscursor = scursor;
  if ( parseMailbox( scursor, send, maybeMailbox, isCRLF ) ) {
    // yes, it is:
    result.displayName = TQString();
    result.mailboxList.append( maybeMailbox );
    return true;
  }
  scursor = oldscursor;
 
  Address maybeAddress;
 
  // no, it's not a single mailbox. Try if it's a group:
  if ( !parseGroup( scursor, send, maybeAddress, isCRLF ) )
    return false;
 
  result = maybeAddress;
  return true;
}
 
bool parseAddressList( const char* & scursor, const char * const send,
               AddressList & result, bool isCRLF ) {
  while ( scursor != send ) {
    eatCFWS( scursor, send, isCRLF );
    // end of header: this is OK.
    if ( scursor == send ) return true;
    // empty entry: ignore:
    if ( *scursor == ',' ) { scursor++; continue; }
 
    // parse one entry
    Address maybeAddress;
    if ( !parseAddress( scursor, send, maybeAddress, isCRLF ) ) return false;
    result.append( maybeAddress );
 
    eatCFWS( scursor, send, isCRLF );
    // end of header: this is OK.
    if ( scursor == send ) return true;
    // comma separating entries: eat it.
    if ( *scursor == ',' ) scursor++;
  }
  return true;
}
 
 
static TQString asterisk = TQString::fromLatin1("*0*",1);
static TQString asteriskZero = TQString::fromLatin1("*0*",2);
//static TQString asteriskZeroAsterisk = TQString::fromLatin1("*0*",3);
 
bool parseParameter( const char* & scursor, const char * const send,
             TQPair<TQString,TQStringOrTQPair> & result, bool isCRLF ) {
  // parameter = regular-parameter / extended-parameter
  // regular-parameter = regular-parameter-name "=" value
  // extended-parameter =
  // value = token / quoted-string
  //
  // note that rfc2231 handling is out of the scope of this function.
  // Therefore we return the attribute as TQString and the value as
  // (start,length) tupel if we see that the value is encoded
  // (trailing asterisk), for parseParameterList to decode...
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  //
  // parse the parameter name:
  //
  TQString maybeAttribute;
  if ( !parseToken( scursor, send, maybeAttribute, false /* no 8bit */ ) )
    return false;
 
  eatCFWS( scursor, send, isCRLF );
  // premature end: not OK (haven't seen '=' yet).
  if ( scursor == send || *scursor != '=' ) return false;
  scursor++; // eat '='
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) {
    // don't choke on attribute=, meaning the value was omitted:
    if ( maybeAttribute.endsWith( asterisk ) ) {
      KMIME_WARN << "attribute ends with \"*\", but value is empty! "
    "Chopping away \"*\"." << endl;
      maybeAttribute.truncate( maybeAttribute.length() - 1 );
    }
    result = qMakePair( maybeAttribute.lower(), TQStringOrTQPair() );
    return true;
  }
 
  const char * oldscursor = scursor;
 
  //
  // parse the parameter value:
  //
  TQStringOrTQPair maybeValue;
  if ( *scursor == '"' ) {
    // value is a quoted-string:
    scursor++;
    if ( maybeAttribute.endsWith( asterisk ) ) {
      // attributes ending with "*" designate extended-parameters,
      // which cannot have quoted-strings as values. So we remove the
      // trailing "*" to not confuse upper layers.
      KMIME_WARN << "attribute ends with \"*\", but value is a quoted-string! "
    "Chopping away \"*\"." << endl;
      maybeAttribute.truncate( maybeAttribute.length() - 1 );
    }
 
    if ( !parseGenericQuotedString( scursor, send, maybeValue.qstring, isCRLF ) ) {
      scursor = oldscursor;
      result = qMakePair( maybeAttribute.lower(), TQStringOrTQPair() );
      return false; // this case needs further processing by upper layers!!
    }
  } else {
    // value is a token:
    if ( !parseToken( scursor, send, maybeValue.qpair, false /* no 8bit */ ) ) {
      scursor = oldscursor;
      result = qMakePair( maybeAttribute.lower(), TQStringOrTQPair() );
      return false; // this case needs further processing by upper layers!!
    }
  }
 
  result = qMakePair( maybeAttribute.lower(), maybeValue );
  return true;
}
 
 
 
bool parseRawParameterList( const char* & scursor, const char * const send,
                TQMap<TQString,TQStringOrTQPair> & result,
                bool isCRLF ) {
  // we use parseParameter() consecutively to obtain a map of raw
  // attributes to raw values. "Raw" here means that we don't do
  // rfc2231 decoding and concatenation. This is left to
  // parseParameterList(), which will call this function.
  //
  // The main reason for making this chunk of code a separate
  // (private) method is that we can deal with broken parameters
  // _here_ and leave the rfc2231 handling solely to
  // parseParameterList(), which will still be enough work.
 
  while ( scursor != send ) {
    eatCFWS( scursor, send, isCRLF );
    // empty entry ending the list: OK.
    if ( scursor == send ) return true;
    // empty list entry: ignore.
    if ( *scursor == ';' ) { scursor++; continue; }
 
    TQPair<TQString,TQStringOrTQPair> maybeParameter;
    if ( !parseParameter( scursor, send, maybeParameter, isCRLF ) ) {
      // we need to do a bit of work if the attribute is not
      // NULL. These are the cases marked with "needs further
      // processing" in parseParameter(). Specifically, parsing of the
      // token or the quoted-string, which should represent the value,
      // failed. We take the easy way out and simply search for the
      // next ';' to start parsing again. (Another option would be to
      // take the text between '=' and ';' as value)
      if ( maybeParameter.first.isNull() ) return false;
      while ( scursor != send ) {
    if ( *scursor++ == ';' ) goto IS_SEMICOLON;
      }
      // scursor == send case: end of list.
      return true;
    IS_SEMICOLON:
      // *scursor == ';' case: parse next entry.
      continue;
    }
    // successful parsing brings us here:
    result.insert( maybeParameter.first, maybeParameter.second );
 
    eatCFWS( scursor, send, isCRLF );
    // end of header: ends list.
    if ( scursor == send ) return true;
    // regular separator: eat it.
    if ( *scursor == ';' ) scursor++;
  }
  return true;
}
 
 
static void decodeRFC2231Value( Codec* & rfc2231Codec,
                TQTextCodec* & textcodec,
                bool isContinuation, TQString & value,
                TQPair<const char*,int> & source ) {
 
  //
  // parse the raw value into (charset,language,text):
  //
 
  const char * decBegin = source.first;
  const char * decCursor = decBegin;
  const char * decEnd = decCursor + source.second;
 
  if ( !isContinuation ) {
    // find the first single quote
    while ( decCursor != decEnd ) {
      if ( *decCursor == '\'' ) break;
      else decCursor++;
    }
 
    if ( decCursor == decEnd ) {
      // there wasn't a single single quote at all!
      // take the whole value to be in latin-1:
      KMIME_WARN << "No charset in extended-initial-value. "
    "Assuming \"iso-8859-1\"." << endl;
      value += TQString::fromLatin1( decBegin, source.second );
      return;
    }
 
    TQCString charset( decBegin, decCursor - decBegin + 1 );
 
    const char * oldDecCursor = ++decCursor;
    // find the second single quote (we ignore the language tag):
    while ( decCursor != decEnd ) {
      if ( *decCursor == '\'' ) break;
      else decCursor++;
    }
    if ( decCursor == decEnd ) {
      KMIME_WARN << "No language in extended-initial-value. "
    "Trying to recover." << endl;
      decCursor = oldDecCursor;
    } else
      decCursor++;
 
    // decCursor now points to the start of the
    // "extended-other-values":
 
    //
    // get the decoders:
    //
 
    bool matchOK = false;
    textcodec = TDEGlobal::charsets()->codecForName( charset, matchOK );
    if ( !matchOK ) {
      textcodec = 0;
      KMIME_WARN_UNKNOWN(Charset,charset);
    }
  }
 
  if ( !rfc2231Codec ) {
    rfc2231Codec = Codec::codecForName("x-kmime-rfc2231");
    assert( rfc2231Codec );
  }
 
  if ( !textcodec ) {
    value += TQString::fromLatin1( decCursor, decEnd - decCursor );
    return;
  }
 
  Decoder * dec = rfc2231Codec->makeDecoder();
  assert( dec );
 
  //
  // do the decoding:
  //
 
  TQByteArray buffer( rfc2231Codec->maxDecodedSizeFor( decEnd - decCursor ) );
  TQByteArray::Iterator bit = buffer.begin();
  TQByteArray::ConstIterator bend = buffer.end();
 
  if ( !dec->decode( decCursor, decEnd, bit, bend ) )
    KMIME_WARN << rfc2231Codec->name()
           << " codec lies about it's maxDecodedSizeFor()\n"
      "result may be truncated" << endl;
 
  value += textcodec->toUnicode( buffer.begin(), bit - buffer.begin() );
 
  kdDebug() << "value now: \"" << value << "\"" << endl;
  // cleanup:
  delete dec;
}
 
// known issues:
//  - permutes rfc2231 continuations when the total number of parts
//    exceeds 10 (other-sections then becomes *xy, ie. two digits)
 
bool parseParameterList( const char* & scursor, const char * const send,
             TQMap<TQString,TQString> & result, bool isCRLF ) {
  // parse the list into raw attribute-value pairs:
  TQMap<TQString,TQStringOrTQPair> rawParameterList;
  if (!parseRawParameterList( scursor, send, rawParameterList, isCRLF ) )
    return false;
 
  if ( rawParameterList.isEmpty() ) return true;
 
  // decode rfc 2231 continuations and alternate charset encoding:
 
  // NOTE: this code assumes that what TQMapIterator delivers is sorted
  // by the key!
 
  Codec * rfc2231Codec = 0;
  TQTextCodec * textcodec = 0;
  TQString attribute;
  TQString value;
  enum Modes { NoMode = 0x0, Continued = 0x1, Encoded = 0x2 } mode;
 
  TQMapIterator<TQString,TQStringOrTQPair> it, end = rawParameterList.end();
 
  for ( it = rawParameterList.begin() ; it != end ; ++it ) {
    if ( attribute.isNull() || !it.key().startsWith( attribute ) ) {
      //
      // new attribute:
      //
 
      // store the last attribute/value pair in the result map now:
      if ( !attribute.isNull() ) result.insert( attribute, value );
      // and extract the information from the new raw attribute:
      value = TQString();
      attribute = it.key();
      mode = NoMode;
      // is the value encoded?
      if ( attribute.endsWith( asterisk ) ) {
    attribute.truncate( attribute.length() - 1 );
    mode = (Modes) ((int) mode | Encoded);
      }
      // is the value continued?
      if ( attribute.endsWith( asteriskZero ) ) {
    attribute.truncate( attribute.length() - 2 );
    mode = (Modes) ((int) mode | Continued);
      }
      //
      // decode if necessary:
      //
      if ( mode & Encoded ) {
    decodeRFC2231Value( rfc2231Codec, textcodec,
                false, /* isn't continuation */
                value, (*it).qpair );
      } else {
    // not encoded.
    if ( (*it).qpair.first )
      value += TQString::fromLatin1( (*it).qpair.first, (*it).qpair.second );
    else
      value += (*it).qstring;
      }
 
      //
      // shortcut-processing when the value isn't encoded:
      //
 
      if ( !(mode & Continued) ) {
    // save result already:
    result.insert( attribute, value );
    // force begin of a new attribute:
    attribute = TQString();
      }
    } else /* it.key().startsWith( attribute ) */ {
      //
      // continuation
      //
 
      // ignore the section and trust TQMap to have sorted the keys:
      if ( it.key().endsWith( asterisk ) ) {
    // encoded
    decodeRFC2231Value( rfc2231Codec, textcodec,
                true, /* is continuation */
                value, (*it).qpair );
      } else {
    // not encoded
    if ( (*it).qpair.first )
      value += TQString::fromLatin1( (*it).qpair.first, (*it).qpair.second );
    else
      value += (*it).qstring;
      }
    }
  }
 
  // write last attr/value pair:
  if ( !attribute.isNull() )
    result.insert( attribute, value );
 
  return true;
}
 
static const char * stdDayNames[] = {
  "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};
static const int stdDayNamesLen = sizeof stdDayNames / sizeof *stdDayNames;
 
static bool parseDayName( const char* & scursor, const char * const send )
{
  // check bounds:
  if ( send - scursor < 3 ) return false;
 
  for ( int i = 0 ; i < stdDayNamesLen ; ++i )
    if ( tqstrnicmp( scursor, stdDayNames[i], 3 ) == 0 ) {
      scursor += 3;
      kdDebug() << "found " << stdDayNames[i] << endl;
      return true;
    }
 
  return false;
}
 
 
static const char * stdMonthNames[] = {
  "Jan", "Feb", "Mar", "Apr", "May", "Jun",
  "Jul", "Aug", "Sep", "Oct", "Nov", "Dez"
};
static const int stdMonthNamesLen =
  sizeof stdMonthNames / sizeof *stdMonthNames;
 
static bool parseMonthName( const char* & scursor, const char * const send,
                int & result )
{
  // check bounds:
  if ( send - scursor < 3 ) return false;
 
  for ( result = 0 ; result < stdMonthNamesLen ; ++result )
    if ( tqstrnicmp( scursor, stdMonthNames[result], 3 ) == 0 ) {
      scursor += 3;
      return true;
    }
 
  // not found:
  return false;
}
 
static const struct {
  const char * tzName;
  long int secsEastOfGMT;
} timeZones[] = {
  // rfc 822 timezones:
  { "GMT", 0 },
  { "UT", 0 },
  { "EDT", -4*3600 },
  { "EST", -5*3600 },
  { "MST", -5*3600 },
  { "CST", -6*3600 },
  { "MDT", -6*3600 },
  { "MST", -7*3600 },
  { "PDT", -7*3600 },
  { "PST", -8*3600 },
  // common, non-rfc-822 zones:
  { "CET", 1*3600 },
  { "MET", 1*3600 },
  { "UTC", 0 },
  { "CEST", 2*3600 },
  { "BST", 1*3600 },
  // rfc 822 military timezones:
  { "Z", 0 },
  { "A", -1*3600 },
  { "B", -2*3600 },
  { "C", -3*3600 },
  { "D", -4*3600 },
  { "E", -5*3600 },
  { "F", -6*3600 },
  { "G", -7*3600 },
  { "H", -8*3600 },
  { "I", -9*3600 },
  // J is not used!
  { "K", -10*3600 },
  { "L", -11*3600 },
  { "M", -12*3600 },
  { "N", 1*3600 },
  { "O", 2*3600 },
  { "P", 3*3600 },
  { "Q", 4*3600 },
  { "R", 5*3600 },
  { "S", 6*3600 },
  { "T", 7*3600 },
  { "U", 8*3600 },
  { "V", 9*3600 },
  { "W", 10*3600 },
  { "X", 11*3600 },
  { "Y", 12*3600 },
};
static const int timeZonesLen = sizeof timeZones / sizeof *timeZones;
 
static bool parseAlphaNumericTimeZone( const char* & scursor,
                       const char * const send,
                       long int & secsEastOfGMT,
                       bool & timeZoneKnown )
{
  TQPair<const char*,int> maybeTimeZone(0,0);
  if ( !parseToken( scursor, send, maybeTimeZone, false /*no 8bit*/ ) )
    return false;
  for ( int i = 0 ; i < timeZonesLen ; ++i )
    if ( tqstrnicmp( timeZones[i].tzName,
            maybeTimeZone.first, maybeTimeZone.second ) == 0 ) {
      scursor += maybeTimeZone.second;
      secsEastOfGMT = timeZones[i].secsEastOfGMT;
      timeZoneKnown = true;
      return true;
    }
 
  // don't choke just because we don't happen to know the time zone
  KMIME_WARN_UNKNOWN(time zone,TQCString( maybeTimeZone.first, maybeTimeZone.second+1 ));
  secsEastOfGMT = 0;
  timeZoneKnown = false;
  return true;
}
 
// parse a number and return the number of digits parsed:
static int parseDigits( const char* & scursor, const char * const send,
            int & result )
{
  result = 0;
  int digits = 0;
  for ( ; scursor != send && isdigit( *scursor ) ; scursor++, digits++ ) {
    result *= 10;
    result += int( *scursor - '0' );
  }
  return digits;
}
 
static bool parseTimeOfDay( const char* & scursor, const char * const send,
                int & hour, int & min, int & sec, bool isCRLF=false )
{
  // time-of-day := 2DIGIT [CFWS] ":" [CFWS] 2DIGIT [ [CFWS] ":" 2DIGIT ]
 
  //
  // 2DIGIT representing "hour":
  //
  if ( !parseDigits( scursor, send, hour ) ) return false;
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send || *scursor != ':' ) return false;
  scursor++; // eat ':'
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  //
  // 2DIGIT representing "minute":
  //
  if ( !parseDigits( scursor, send, min ) ) return false;
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return true; // seconds are optional
 
  //
  // let's see if we have a 2DIGIT representing "second":
  //
  if ( *scursor == ':' ) {
    // yepp, there are seconds:
    scursor++; // eat ':'
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
 
    if ( !parseDigits( scursor, send, sec ) ) return false;
  } else {
    sec = 0;
  }
 
  return true;
}
 
 
bool parseTime( const char* & scursor, const char * send,
        int & hour, int & min, int & sec, long int & secsEastOfGMT,
        bool & timeZoneKnown, bool isCRLF )
{
  // time := time-of-day CFWS ( zone / obs-zone )
  //
  // obs-zone    := "UT" / "GMT" /
  //                "EST" / "EDT" / ; -0500 / -0400
  //                "CST" / "CDT" / ; -0600 / -0500
  //                "MST" / "MDT" / ; -0700 / -0600
  //                "PST" / "PDT" / ; -0800 / -0700
  //                "A"-"I" / "a"-"i" /
  //                "K"-"Z" / "k"-"z"
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  if ( !parseTimeOfDay( scursor, send, hour, min, sec, isCRLF ) )
    return false;
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) {
    timeZoneKnown = false;
    secsEastOfGMT = 0;
    return true; // allow missing timezone
  }
 
  timeZoneKnown = true;
  if ( *scursor == '+' || *scursor == '-' ) {
    // remember and eat '-'/'+':
    const char sign = *scursor++;
    // numerical timezone:
    int maybeTimeZone;
    if ( parseDigits( scursor, send, maybeTimeZone ) != 4 ) return false;
    secsEastOfGMT = 60 * ( maybeTimeZone / 100 * 60 + maybeTimeZone % 100 );
    if ( sign == '-' ) {
      secsEastOfGMT *= -1;
      if ( secsEastOfGMT == 0 )
    timeZoneKnown = false; // -0000 means indetermined tz
    }
  } else {
    // maybe alphanumeric timezone:
    if ( !parseAlphaNumericTimeZone( scursor, send, secsEastOfGMT, timeZoneKnown ) )
      return false;
  }
  return true;
}
 
 
bool parseDateTime( const char* & scursor, const char * const send,
            Types::DateTime & result, bool isCRLF )
{
  // Parsing date-time; strict mode:
  //
  // date-time   := [ [CFWS] day-name [CFWS] "," ]                      ; wday
  // (expanded)     [CFWS] 1*2DIGIT CFWS month-name CFWS 2*DIGIT [CFWS] ; date
  //                time
  //
  // day-name    := "Mon" / "Tue" / "Wed" / "Thu" / "Fri" / "Sat" / "Sun"
  // month-name  := "Jan" / "Feb" / "Mar" / "Apr" / "May" / "Jun" /
  //                "Jul" / "Aug" / "Sep" / "Oct" / "Nov" / "Dez"
 
  struct tm maybeDateTime = {
#ifdef HAVE_TM_GMTOFF
    0, 0, // initializers for members tm_gmtoff and tm_zone
#endif
    0, 0, 0, 0, 0, 0, 0, 0, 0
  };
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  //
  // let's see if there's a day-of-week:
  //
  if ( parseDayName( scursor, send ) ) {
    eatCFWS( scursor, send, isCRLF );
    if ( scursor == send ) return false;
    // day-name should be followed by ',' but we treat it as optional:
    if ( *scursor == ',' ) {
      scursor++; // eat ','
      eatCFWS( scursor, send, isCRLF );
    }
  }
 
  //
  // 1*2DIGIT representing "day" (of month):
  //
  int maybeDay;
  if ( !parseDigits( scursor, send, maybeDay ) ) return false;
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // success: store maybeDay in maybeDateTime:
  maybeDateTime.tm_mday = maybeDay;
 
  //
  // month-name:
  //
  int maybeMonth = 0;
  if ( !parseMonthName( scursor, send, maybeMonth ) ) return false;
  if ( scursor == send ) return false;
  assert( maybeMonth >= 0 ); assert( maybeMonth <= 11 );
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // success: store maybeMonth in maybeDateTime:
  maybeDateTime.tm_mon = maybeMonth;
 
  //
  // 2*DIGIT representing "year":
  //
  int maybeYear;
  if ( !parseDigits( scursor, send, maybeYear ) ) return false;
  // RFC 2822 4.3 processing:
  if ( maybeYear < 50 )
    maybeYear += 2000;
  else if ( maybeYear < 1000 )
    maybeYear += 1900;
  // else keep as is
  if ( maybeYear < 1900 ) return false; // rfc2822, 3.3
 
  eatCFWS( scursor, send, isCRLF );
  if ( scursor == send ) return false;
 
  // success: store maybeYear in maybeDateTime:
  maybeDateTime.tm_year = maybeYear - 1900;
 
  //
  // time
  //
  int maybeHour, maybeMinute, maybeSecond;
  long int secsEastOfGMT;
  bool timeZoneKnown = true;
 
  if ( !parseTime( scursor, send,
           maybeHour, maybeMinute, maybeSecond,
           secsEastOfGMT, timeZoneKnown, isCRLF ) )
    return false;
 
  // success: store everything in maybeDateTime:
  maybeDateTime.tm_hour = maybeHour;
  maybeDateTime.tm_min = maybeMinute;
  maybeDateTime.tm_sec = maybeSecond;
  maybeDateTime.tm_isdst = DateFormatter::isDaylight();
  // now put everything together and check if mktime(3) likes it:
  result.time = mktime( &maybeDateTime );
  if ( result.time == (time_t)(-1) ) return false;
 
  // adjust to UTC/GMT:
  //result.time -= secsEastOfGMT;
  result.secsEastOfGMT = secsEastOfGMT;
  result.timeZoneKnown = timeZoneKnown;
 
  return true;
}
 
#if 0
bool tryToMakeAnySenseOfDateString( const char* & scursor,
                    const char * const send,
                    time_t & result, bool isCRLF )
{
  return false;
}
#endif
 
} // namespace HeaderParsing
 
} // namespace KMime