mitab_datfile.cpp

GIS系统支持库Geospatial Data Abstraction Library代码.GDAL is a translator library for raster geospatial dat

 *
 * Write the character field value at the current position in the data 
 * block.
 * 
 * Use GetRecordBlock() to position the data block to the beginning of
 * a record before attempting to write values.
 *
 * nWidth is the field length, as defined in the .DAT header.
 *
 * Returns 0 on success, or -1 if the operation failed, in which case
 * CPLError() will have been called.
 **********************************************************************/
int TABDATFile::WriteCharField(const char *pszStr, int nWidth,
                               TABINDFile *poINDFile, int nIndexNo)
{
    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    if (nWidth < 1 || nWidth > 255)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
                 "Illegal width for a char field: %d", nWidth);
        return -1;
    }
    
    //
    // Write the buffer after making sure that we don't try to read
    // past the end of the source buffer.  The rest of the field will
    // be padded with zeros if source string is shorter than specified
    // field width.
    //
    int nLen = strlen(pszStr);
    nLen = MIN(nLen, nWidth);

    if ((nLen>0 && m_poRecordBlock->WriteBytes(nLen, (GByte*)pszStr) != 0) ||
        (nWidth-nLen > 0 && m_poRecordBlock->WriteZeros(nWidth-nLen)!=0) )
        return -1;

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, pszStr);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return 0;
}

/**********************************************************************
 *                   TABDATFile::WriteIntegerField()
 *
 * Write the integer field value at the current position in the data 
 * block.
 * 
 * CPLError() will have been called if something fails.
 **********************************************************************/
int TABDATFile::WriteIntegerField(GInt32 nValue,
                                  TABINDFile *poINDFile, int nIndexNo)
{
    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, nValue);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return m_poRecordBlock->WriteInt32(nValue);
}

/**********************************************************************
 *                   TABDATFile::WriteSmallIntField()
 *
 * Write the smallint field value at the current position in the data 
 * block.
 * 
 * CPLError() will have been called if something fails.
 **********************************************************************/
int TABDATFile::WriteSmallIntField(GInt16 nValue,
                                   TABINDFile *poINDFile, int nIndexNo)
{
    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, nValue);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return m_poRecordBlock->WriteInt16(nValue);
}

/**********************************************************************
 *                   TABDATFile::WriteFloatField()
 *
 * Write the float field value at the current position in the data 
 * block.
 * 
 * CPLError() will have been called if something fails.
 **********************************************************************/
int TABDATFile::WriteFloatField(double dValue,
                                TABINDFile *poINDFile, int nIndexNo)
{
    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, dValue);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return m_poRecordBlock->WriteDouble(dValue);
}

/**********************************************************************
 *                   TABDATFile::WriteLogicalField()
 *
 * Write the logical field value at the current position in the data 
 * block.
 *
 * The value written to the file is either 0 or 1, but this function
 * takes as input a string with "F" (false) or "T" (true)
 * 
 * CPLError() will have been called if something fails.
 **********************************************************************/
int TABDATFile::WriteLogicalField(const char *pszValue,
                                  TABINDFile *poINDFile, int nIndexNo)
{
    GByte bValue;

    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    if (EQUALN(pszValue, "T", 1))
        bValue = 1;
    else
        bValue = 0;

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, (int)bValue);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return m_poRecordBlock->WriteByte(bValue);
}

/**********************************************************************
 *                   TABDATFile::WriteDateField()
 *
 * Write the date field value at the current position in the data 
 * block.
 *
 * A date field is a 4 bytes binary value in which the first byte is
 * the day, followed by 1 byte for the month, and 2 bytes for the year.
 *
 * The expected input is a 10 chars string in the format "YYYY/MM/DD"
 * or "DD/MM/YYYY" or "YYYYMMDD"
 * 
 * Returns 0 on success, or -1 if the operation failed, in which case
 * CPLError() will have been called.
 **********************************************************************/
int TABDATFile::WriteDateField(const char *pszValue,
                               TABINDFile *poINDFile, int nIndexNo)
{
    int nDay, nMonth, nYear;
    char **papszTok = NULL;

    if (m_poRecordBlock == NULL)
    {
        CPLError(CE_Failure, CPLE_AssertionFailed,
            "Can't write field value: GetRecordBlock() has not been called.");
        return -1;
    }

    /*-----------------------------------------------------------------
     * Get rid of leading spaces.
     *----------------------------------------------------------------*/
    while ( *pszValue == ' ' ) { pszValue++; }

    /*-----------------------------------------------------------------
     * Try to automagically detect date format, one of:
     * "YYYY/MM/DD", "DD/MM/YYYY", or "YYYYMMDD"
     *----------------------------------------------------------------*/
    
    if (strlen(pszValue) == 8)
    {
        /*-------------------------------------------------------------
         * "YYYYMMDD"
         *------------------------------------------------------------*/
        char szBuf[9];
        strcpy(szBuf, pszValue);
        nDay = atoi(szBuf+6);
        szBuf[6] = '\0';
        nMonth = atoi(szBuf+4);
        szBuf[4] = '\0';
        nYear = atoi(szBuf);
    }
    else if (strlen(pszValue) == 10 &&
             (papszTok = CSLTokenizeStringComplex(pszValue, "/", 
                                                  FALSE, FALSE)) != NULL &&
             CSLCount(papszTok) == 3 &&
             (strlen(papszTok[0]) == 4 || strlen(papszTok[2]) == 4) )
    {
        /*-------------------------------------------------------------
         * Either "YYYY/MM/DD" or "DD/MM/YYYY"
         *------------------------------------------------------------*/
        if (strlen(papszTok[0]) == 4)
        {
            nYear = atoi(papszTok[0]);
            nMonth = atoi(papszTok[1]);
            nDay = atoi(papszTok[2]);
        }
        else
        {
            nYear = atoi(papszTok[2]);
            nMonth = atoi(papszTok[1]);
            nDay = atoi(papszTok[0]);
        }
    }
    else if (strlen(pszValue) == 0)
    {
        nYear = nMonth = nDay = 0;
    }
    else
    {
        CPLError(CE_Failure, CPLE_AppDefined,
                 "Invalid date field value `%s'.  Date field values must "
                 "be in the format `YYYY/MM/DD', `MM/DD/YYYY' or `YYYYMMDD'",
                 pszValue);
        CSLDestroy(papszTok);
        return -1;
    }
    CSLDestroy(papszTok);

    m_poRecordBlock->WriteInt16(nYear);
    m_poRecordBlock->WriteByte(nMonth);
    m_poRecordBlock->WriteByte(nDay);

    if (CPLGetLastErrorNo() != 0)
        return -1;

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, (nYear*0x10000 +
                                                     nMonth * 0x100 + nDay));
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return 0;
}

/**********************************************************************
 *                   TABDATFile::WriteDecimalField()
 *
 * Write the decimal field value at the current position in the data 
 * block.
 *
 * A decimal field is a floating point value with a fixed number of digits
 * stored as a character string.
 *
 * nWidth is the field length, as defined in the .DAT header.
 *
 * CPLError() will have been called if something fails.
 **********************************************************************/
int TABDATFile::WriteDecimalField(double dValue, int nWidth, int nPrec,
                                  TABINDFile *poINDFile, int nIndexNo)
{
    const char *pszVal;

    pszVal = CPLSPrintf("%*.*f", nWidth, nPrec, dValue);
    if ((int)strlen(pszVal) > nWidth)
        pszVal += strlen(pszVal) - nWidth;

    // Update Index
    if (poINDFile && nIndexNo > 0)
    {
        GByte *pKey = poINDFile->BuildKey(nIndexNo, dValue);
        if (poINDFile->AddEntry(nIndexNo, pKey, m_nCurRecordId) != 0)
            return -1;
    }

    return m_poRecordBlock->WriteBytes(nWidth, (GByte*)pszVal);
}



/**********************************************************************
 *                   TABDATFile::Dump()
 *
 * Dump block contents... available only in DEBUG mode.
 **********************************************************************/
#ifdef DEBUG

void TABDATFile::Dump(FILE *fpOut /*=NULL*/)
{
    if (fpOut == NULL)
        fpOut = stdout;

    fprintf(fpOut, "----- TABDATFile::Dump() -----\n");

    if (m_fp == NULL)
    {
        fprintf(fpOut, "File is not opened.\n");
    }
    else
    {
        fprintf(fpOut, "File is opened: %s\n", m_pszFname);
        fprintf(fpOut, "m_numFields  = %d\n", m_numFields);
        fprintf(fpOut, "m_numRecords = %d\n", m_numRecords);
    }

    fflush(fpOut);
}

#endif // DEBUG