qtextstream.cpp

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

	} else {
	    if ( !(c == '-' || c == '+') )
		ts_ungetc( ch );
	    if ( c == '-' ) {
		ulong v = input_dec();
		if ( v ) {		// ensure that LONG_MIN can be read
		    v--;
		    val = -((long)v) - 1;
		} else {
		    val = 0;
		}
	    } else {
		val = (long)input_dec();
	    }
	}
	break;
    case hex:
	val = (long)input_hex();
	break;
    default:
	val = 0;
	c = ch = eat_ws();
	if ( c == '0' ) {		// bin, oct or hex
	    c = ch = ts_getc();
	    if ( tolower((uchar) c) == 'x' )
		val = (long)input_hex();
	    else if ( tolower((uchar) c) == 'b' )
		val = (long)input_bin();
	    else {			// octal
		ts_ungetc( ch );
		if ( c >= '0' && c <= '7' ) {
		    val = (long)input_oct();
		} else {
		    val = 0;
		}
	    }
	} else if ( ts_isdigit(ch) ) {
	    ts_ungetc( ch );
	    val = (long)input_dec();
	} else if ( c == '-' || c == '+' ) {
	    ulong v = input_dec();
	    if ( c == '-' ) {
		if ( v ) {		// ensure that LONG_MIN can be read
		    v--;
		    val = -((long)v) - 1;
		} else {
		    val = 0;
		}
	    } else {
		val = (long)v;
	    }
	}
    }
    return val;
}

//
// We use a table-driven FSM to parse floating point numbers
// strtod() cannot be used directly since we're reading from a QIODevice
//

double QTextStream::input_double()
{
    const int Init	 = 0;			// states
    const int Sign	 = 1;
    const int Mantissa	 = 2;
    const int Dot	 = 3;
    const int Abscissa	 = 4;
    const int ExpMark	 = 5;
    const int ExpSign	 = 6;
    const int Exponent	 = 7;
    const int Done	 = 8;

    const int InputSign	 = 1;			// input tokens
    const int InputDigit = 2;
    const int InputDot	 = 3;
    const int InputExp	 = 4;

    static const uchar table[8][5] = {
     /* None	 InputSign   InputDigit InputDot InputExp */
	{ 0,	    Sign,     Mantissa,	 Dot,	   0,	   }, // Init
	{ 0,	    0,	      Mantissa,	 Dot,	   0,	   }, // Sign
	{ Done,	    Done,     Mantissa,	 Dot,	   ExpMark,}, // Mantissa
	{ 0,	    0,	      Abscissa,	 0,	   0,	   }, // Dot
	{ Done,	    Done,     Abscissa,	 Done,	   ExpMark,}, // Abscissa
	{ 0,	    ExpSign,  Exponent,	 0,	   0,	   }, // ExpMark
	{ 0,	    0,	      Exponent,	 0,	   0,	   }, // ExpSign
	{ Done,	    Done,     Exponent,	 Done,	   Done	   }  // Exponent
    };

    int state = Init;				// parse state
    int input;					// input token

    char buf[256];
    int i = 0;
    QChar c = eat_ws();

    for (;;) {

	switch ( c ) {
	    case '+':
	    case '-':
		input = InputSign;
		break;
	    case '0': case '1': case '2': case '3': case '4':
	    case '5': case '6': case '7': case '8': case '9':
		input = InputDigit;
		break;
	    case '.':
		input = InputDot;
		break;
	    case 'e':
	    case 'E':
		input = InputExp;
		break;
	    default:
		input = 0;
		break;
	}

	state = table[state][input];

	if  ( state == 0 || state == Done || i > 250 ) {
	    if ( i > 250 ) {			// ignore rest of digits
		do { c = ts_getc(); } while ( c != QEOF && ts_isdigit(c) );
	    }
	    if ( c != QEOF )
		ts_ungetc( c );
	    buf[i] = '\0';
	    char *end;
	    return strtod( buf, &end );
	}

	buf[i++] = c;
	c = ts_getc();
    }

#if !defined(Q_CC_EDG)
    return 0.0;
#endif
}


/*!
    \overload

    Reads a signed \c short integer \a i from the stream and returns a
    reference to the stream. See flags() for an explanation of the
    expected input format.
*/

QTextStream &QTextStream::operator>>( signed short &i )
{
    CHECK_STREAM_PRECOND
    i = (signed short)input_int();
    return *this;
}


/*!
    \overload

    Reads an unsigned \c short integer \a i from the stream and
    returns a reference to the stream. See flags() for an explanation
    of the expected input format.
*/

QTextStream &QTextStream::operator>>( unsigned short &i )
{
    CHECK_STREAM_PRECOND
    i = (unsigned short)input_int();
    return *this;
}


/*!
    \overload

    Reads a signed \c int \a i from the stream and returns a reference
    to the stream. See flags() for an explanation of the expected
    input format.
*/

QTextStream &QTextStream::operator>>( signed int &i )
{
    CHECK_STREAM_PRECOND
    i = (signed int)input_int();
    return *this;
}


/*!
    \overload

    Reads an unsigned \c int \a i from the stream and returns a
    reference to the stream. See flags() for an explanation of the
    expected input format.
*/

QTextStream &QTextStream::operator>>( unsigned int &i )
{
    CHECK_STREAM_PRECOND
    i = (unsigned int)input_int();
    return *this;
}


/*!
    \overload

    Reads a signed \c long int \a i from the stream and returns a
    reference to the stream. See flags() for an explanation of the
    expected input format.
*/

QTextStream &QTextStream::operator>>( signed long &i )
{
    CHECK_STREAM_PRECOND
    i = (signed long)input_int();
    return *this;
}


/*!
    \overload

    Reads an unsigned \c long int \a i from the stream and returns a
    reference to the stream. See flags() for an explanation of the
    expected input format.
*/

QTextStream &QTextStream::operator>>( unsigned long &i )
{
    CHECK_STREAM_PRECOND
    i = (unsigned long)input_int();
    return *this;
}


/*!
    \overload

    Reads a \c float \a f from the stream and returns a reference to
    the stream. See flags() for an explanation of the expected input
    format.
*/

QTextStream &QTextStream::operator>>( float &f )
{
    CHECK_STREAM_PRECOND
    f = (float)input_double();
    return *this;
}


/*!
    \overload

    Reads a \c double \a f from the stream and returns a reference to
    the stream. See flags() for an explanation of the expected input
    format.
*/

QTextStream &QTextStream::operator>>( double &f )
{
    CHECK_STREAM_PRECOND
    f = input_double();
    return *this;
}


/*!
    \overload

    Reads a "word" from the stream into \a s and returns a reference
    to the stream.

    A word consists of characters for which isspace() returns FALSE.
*/

QTextStream &QTextStream::operator>>( char *s )
{
    CHECK_STREAM_PRECOND
    int maxlen = width( 0 );
    QChar c = eat_ws();
    if ( !maxlen )
	maxlen = -1;
    while ( c != QEOF ) {
	if ( ts_isspace(c) || maxlen-- == 0 ) {
	    ts_ungetc( c );
	    break;
	}
	*s++ = c;
	c = ts_getc();
    }

    *s = '\0';
    return *this;
}

/*!
    \overload

    Reads a "word" from the stream into \a str and returns a reference
    to the stream.

    A word consists of characters for which isspace() returns FALSE.
*/

QTextStream &QTextStream::operator>>( QString &str )
{
    CHECK_STREAM_PRECOND
    str=QString::fromLatin1("");
    QChar	c = eat_ws();

    while ( c != QEOF ) {
	if ( ts_isspace(c) ) {
	    ts_ungetc( c );
	    break;
	}
	str += c;
	c = ts_getc();
    }
    return *this;
}

/*!
    \overload

    Reads a "word" from the stream into \a str and returns a reference
    to the stream.

    A word consists of characters for which isspace() returns FALSE.
*/

QTextStream &QTextStream::operator>>( QCString &str )
{
    CHECK_STREAM_PRECOND
    QCString  *dynbuf = 0;
    const int buflen = 256;
    char      buffer[buflen];
    char     *s = buffer;
    int	      i = 0;
    QChar	      c = eat_ws();

    while ( c != QEOF ) {
	if ( ts_isspace(c) ) {
	    ts_ungetc( c );
	    break;
	}
	if ( i >= buflen-1 ) {
	    if ( !dynbuf )  {			// create dynamic buffer
		dynbuf = new QCString(buflen*2);
		memcpy( dynbuf->data(), s, i );	// copy old data
	    } else if ( i >= (int)dynbuf->size()-1 ) {
		dynbuf->resize( dynbuf->size()*2 );
	    }
	    s = dynbuf->data();
	}
	s[i++] = c;
	c = ts_getc();
    }
    str.resize( i+1 );
    memcpy( str.data(), s, i );
    delete dynbuf;
    return *this;
}


/*!
    Reads a line from the stream and returns a string containing the
    text.

    The returned string does not contain any trailing newline or
    carriage return. Note that this is different from
    QIODevice::readLine(), which does not strip the newline at the end
    of the line.

    On EOF you will get a QString that is null. On reading an empty
    line the returned QString is empty but not null.

    \sa QIODevice::readLine()
*/

QString QTextStream::readLine()
{
#if defined(QT_CHECK_STATE)
    if ( !dev ) {
	qWarning( "QTextStream::readLine: No device" );
	return QString::null;
    }
#endif
    bool readCharByChar = TRUE;
    QString result;
#if 0
    if ( !doUnicodeHeader && (
	    (latin1) ||
	    (mapper != 0 && mapper->mibEnum() == 106 ) // UTF 8
       ) ) {
	readCharByChar = FALSE;
	// use optimized read line
	QChar c[getline_buf_size];
	int pos = 0;
	bool eof = FALSE;

	for (;;) {
	    pos = ts_getline( c );
	    if ( pos == 0 ) {
		// something went wrong; try fallback
		readCharByChar = TRUE;
		//dev->resetStatus();
		break;
	    }
	    if ( c[pos-1] == QEOF || c[pos-1] == '\n' ) {
		if ( pos>2 && c[pos-1]==QEOF && c[pos-2]=='\n' ) {
		    result += QString( c, pos-2 );
		} else if ( pos > 1 ) {
		    result += QString( c, pos-1 );
		}
		if ( pos == 1 && c[pos-1] == QEOF )
		    eof = TRUE;
		break;
	    } else {
		result += QString( c, pos );
	    }
	}
	if ( eof && result.isEmpty() )
	    return QString::null;
    }
#endif
    if ( readCharByChar ) {
	const int buf_size = 256;
	QChar c[buf_size];
	int pos = 0;

	c[pos] = ts_getc();
	if ( c[pos] == QEOF )
	    return QString::null;

	while ( c[pos] != QEOF && c[pos] != '\n' ) {
	    if ( c[pos] == '\r' ) { // ( handle mac and dos )
		QChar nextc = ts_getc();
		if ( nextc != '\n' )
		    ts_ungetc( nextc );
		break;
	    }
	    pos++;
	    if ( pos >= buf_size ) {
		result += QString( c, pos );
		pos = 0;
	    }
	    c[pos] = ts_getc();
	}
	result += QString( c, pos );
    }

    return result;
}


/*!
    Reads the entire stream and returns a string containing the text.

    \sa QIODevice::readLine()
*/

QString QTextStream::read()
{
#if defined(QT_CHECK_STATE)
    if ( !dev ) {
	qWarning( "QTextStream::read: No device" );
	return QString::null;
    }
#endif
    QString    result;
    const uint bufsize = 512;
    QChar      buf[bufsize];
    uint       i, num, start;
    bool       skipped_cr = FALSE;

    for (;;) {
	num = ts_getbuf(buf,bufsize);
	// convert dos (\r\n) and mac (\r) style eol to unix style (\n)
	start = 0;
	for ( i=0; i<num; i++ ) {
	    if ( buf[i] == '\r' ) {
		// Only skip single cr's preceding lf's
		if ( skipped_cr ) {
		    result += buf[i];
		    start++;
		} else {
		    result += QString( &buf[start], i-start );
		    start = i+1;
		    skipped_cr = TRUE;
		}
	    } else {
		if ( skipped_cr ) {
		    if ( buf[i] != '\n' ) {
			// Should not have skipped it
			result += '\n';
		    }
		    skipped_cr = FALSE;
		}
	    }
	}
	if ( start < num )
	    result += QString( &buf[start], i-start );
	if ( num != bufsize ) // if ( EOF )
	    break;
    }
    return result;
}



/*****************************************************************************
  QTextStream write functions
 *****************************************************************************/

/*!
    Writes character \c char to the stream and returns a reference to
    the stream.

    The character \a c is assumed to be Latin1 encoded independent of
    the Encoding set for the QTextStream.
*/
QTextStream &QTextStream::operator<<( QChar c )
{
    CHECK_STREAM_PRECOND
    ts_putc( c );
    return *this;
}

/*!
    \overload

    Writes character \a c to the stream and returns a reference to the
    stream.
*/
QTextStream &QTextStream::operator<<( char c )
{
    CHECK_STREAM_PRECOND
    unsigned char uc = (unsigned char) c;
    ts_putc( uc );
    return *this;
}

QTextStream &QTextStream::output_int( int format, ulong n, bool neg )
{
    static const char hexdigits_lower[] = "0123456789abcdef";
    static const char hexdigits_upper[] = "0123456789ABCDEF";
    CHECK_STREAM_PRECOND
    char buf[76];
    register char *p;
    int	  len;
    const char *hexdigits;

    switch ( flags() & I_BASE_MASK ) {

	case I_BASE_2:				// output binary number
	    switch ( format & I_TYPE_MASK ) {
		case I_SHORT: len=16; break;
		case I_INT:   len=sizeof(int)*8; break;
		case I_LONG:  len=32; break;
		default:      len = 0;
	    }
	    p = &buf[74];			// go reverse order
	    *p = '\0';
	    while ( len-- ) {
		*--p = (char)(n&1) + '0';
		n >>= 1;
		if ( !n )
		    break;
	    }
	    if ( flags() & showbase ) {		// show base
		*--p = (flags() & uppercase) ? 'B' : 'b';
		*--p = '0';
	    }
	    break;

	case I_BASE_8:				// output octal number
	    p = &buf[74];
	    *p = '\0';
	    do {
		*--p = (char)(n&7) + '0';
		n >>= 3;
	    } while ( n );
	    if ( flags() & showbase )
		*--p = '0';
	    break;

	case I_BASE_16:				// output hexadecimal number
	    p = &buf[74];
	    *p = '\0';
	    hexdigits = (flags() & uppercase) ?
		hexdigits_upper : hexdigits_lower;
	    do {
		*--p = hexdigits[(int)n&0xf];
		n >>= 4;
	    } while ( n );
	    if ( flags() & showbase ) {
		*--p = (flags() & uppercase) ? 'X' : 'x';
		*--p = '0';
	    }
	    break;

	default:				// decimal base is default
	    p = &buf[74];
	    *p = '\0';
	    if ( neg )
		n = (ulong)(-(long)n);
	    do {
		*--p = ((int)(n%10)) + '0';
		n /= 10;
	    } while ( n );
	    if ( neg )
		*--p = '-';
	    else if ( flags() & showpos )
		*--p = '+';
	    if ( (flags() & internal) && fwidth && !ts_isdigit(*p) ) {
		ts_putc( *p );			// special case for internal
		++p;				//   padding
		fwidth--;
		return *this << (const char*)p;
	    }
    }
    if ( fwidth ) {				// adjustment required
	if ( !(flags() & left) ) {		// but NOT left adjustment
	    len = qstrlen(p);
	    int padlen = fwidth - len;
	    if ( padlen <= 0 ) {		// no padding required
		writeBlock( p, len );
	    } else if ( padlen < (int)(p-buf) ) { // speeds up padding
		memset( p-padlen, (char)fillchar, padlen );
		writeBlock( p-padlen, padlen+len );
	    }
	    else				// standard padding
		*this << (const char*)p;
	}
	else
	    *this << (const char*)p;
	fwidth = 0;				// reset field width
    }
    else
	writeBlock( p, qstrlen(p) );
    return *this;
}


/*!