avc_e00read.c

用于读取TAB、MIF、SHP文件的类

                pszName = "ARC";
                break;

            case AVCFilePAL:
                pszName = "PAL";
                break;

            case AVCFileCNT:
                pszName = "CNT";
                break;

            case AVCFileLAB:
                pszName = "LAB";
                break;

            case AVCFileRPL:
                pszName = "RPL";
                break;

            case AVCFileTXT:
                pszName = "TXT";
                break;

            case AVCFileTX6:
                pszName = "TX6";
                break;

            case AVCFilePRJ:
                pszName = "PRJ";
                break;

            case AVCFileTABLE:
                pszName = psInfo->hdr.psTableDef->szTableName;
                break;

            default:
                break;
            }

            if (pszName && (psRead->numSections == 0 ||
                    psRead->pasSections[iSect].eType != psInfo->eFileType ||
                    !EQUAL(pszName, psRead->pasSections[iSect].pszName)))
            {
                iSect = _AVCIncreaseSectionsArray(&(psRead->pasSections), 
                                      &(psRead->numSections), 1);

                psRead->pasSections[iSect].eType = psInfo->eFileType;
                /* psRead->pasSections[iSect].pszName = CPLStrdup(psRead->pszCoverName); */
                psRead->pasSections[iSect].pszName = CPLStrdup(pszName);
                psRead->pasSections[iSect].pszFilename = CPLStrdup(psRead->pszCoverPath);
                psRead->pasSections[iSect].nLineNum = psInfo->nStartLineNum;
                psRead->pasSections[iSect].nFeatureCount = 0;
            }

            if (pszName && psRead->numSections)
            {
                /* increase feature count for current layer */
                ++psRead->pasSections[iSect].nFeatureCount;
            }
        }
    }
}

/**********************************************************************
 *                         _AVCE00ReadNextTableLine()
 *
 * Return the next line of the E00 representation of a info table.
 *
 * This function is used by AVCE00ReadNextLine() to generate table
 * output... it should never be called directly.
 **********************************************************************/
static const char *_AVCE00ReadNextTableLine(AVCE00ReadPtr psInfo)
{
    const char *pszLine = NULL;
    AVCE00Section *psSect;

    psSect = &(psInfo->pasSections[psInfo->iCurSection]);

    CPLAssert(psSect->eType == AVCFileTABLE);

    if (psInfo->iCurStep == AVC_GEN_NOTSTARTED)
    {
        /*---------------------------------------------------------
         * Open table and start returning header
         *--------------------------------------------------------*/
        if (psInfo->eCoverType == AVCCoverPC ||
            psInfo->eCoverType == AVCCoverPC2)
        {
            /*---------------------------------------------------------
             * PC Arc/Info: We pass the DBF table's full filename + the
             * Arc/Info table name (for E00 header)
             *--------------------------------------------------------*/
            char *pszFname;
            pszFname = CPLStrdup(CPLSPrintf("%s%s", psInfo->pszInfoPath,
                                                    psSect->pszFilename ));
            psInfo->hFile = AVCBinReadOpen(pszFname, psSect->pszName, 
                                           psInfo->eCoverType, psSect->eType,
                                           psInfo->psDBCSInfo);
            CPLFree(pszFname);
        }
        else
        {
            /*---------------------------------------------------------
             * AVCCoverV7 and AVCCoverWeird: 
             * We pass the INFO dir's path, and the Arc/Info table name
             * will be searched in the arc.dir
             *--------------------------------------------------------*/
            psInfo->hFile = AVCBinReadOpen(psInfo->pszInfoPath, 
                                           psSect->pszName, 
                                           psInfo->eCoverType, psSect->eType,
                                           psInfo->psDBCSInfo);
        }


        /* For some reason the file could not be opened... abort now.
         * An error message should have already been produced by 
         * AVCBinReadOpen()
         */
        if (psInfo->hFile == NULL)
            return NULL;

        psInfo->iCurStep = AVC_GEN_TABLEHEADER;

        pszLine = AVCE00GenTableHdr(psInfo->hGenInfo,
                                    psInfo->hFile->hdr.psTableDef,
                                    FALSE);
    }
        
    if (pszLine == NULL &&
        psInfo->iCurStep == AVC_GEN_TABLEHEADER)
    {
        /*---------------------------------------------------------
         * Continue table header
         *--------------------------------------------------------*/
        pszLine = AVCE00GenTableHdr(psInfo->hGenInfo,
                                    psInfo->hFile->hdr.psTableDef,
                                    TRUE);

        if (pszLine == NULL)
        {
            /* Finished with table header... time to proceed with the
             * table data.
             * Reset the AVCE00GenInfo struct. so that it returns NULL,
             * which will force reading of the first record from the 
             * file on the next call to AVCE00ReadNextLine()
             */
            AVCE00GenReset(psInfo->hGenInfo);
            psInfo->iCurStep = AVC_GEN_TABLEDATA;
        }

    }

    if (pszLine == NULL &&
        psInfo->iCurStep == AVC_GEN_TABLEDATA)
    {
        /*---------------------------------------------------------
         * Continue with records of data
         *--------------------------------------------------------*/

        pszLine = AVCE00GenTableRec(psInfo->hGenInfo, 
                                    psInfo->hFile->hdr.psTableDef->numFields,
                                    psInfo->hFile->hdr.psTableDef->pasFieldDef,
                                    psInfo->hFile->cur.pasFields,
                                    TRUE);

        if (pszLine == NULL)
        {
            /* Current record is finished generating... we need to read 
             * a new one from the file.
             */
            if (AVCBinReadNextObject(psInfo->hFile) != NULL)
            {
                pszLine = AVCE00GenTableRec(psInfo->hGenInfo, 
                                    psInfo->hFile->hdr.psTableDef->numFields,
                                    psInfo->hFile->hdr.psTableDef->pasFieldDef,
                                    psInfo->hFile->cur.pasFields,
                                    FALSE);
            }            

        }
    }

    if (pszLine == NULL)
    {
        /*---------------------------------------------------------
         * No more lines to output for this table ... Close it.
         *--------------------------------------------------------*/
        AVCBinReadClose(psInfo->hFile);
        psInfo->hFile = NULL;

        /*---------------------------------------------------------
         * And now proceed to the next section...
         * OK, I don't really like recursivity either... but it was
         * the simplest way to do this, and anyways we should never
         * have more than one level of recursivity.
         *--------------------------------------------------------*/
        if (psInfo->bReadAllSections)
            psInfo->iCurSection++;
        else
            psInfo->iCurSection = psInfo->numSections;
        psInfo->iCurStep = AVC_GEN_NOTSTARTED;

        pszLine = AVCE00ReadNextLine(psInfo);
    }

    /*-----------------------------------------------------------------
     * Check for errors... if any error happened, tehn return NULL
     *----------------------------------------------------------------*/
    if (CPLGetLastErrorNo() != 0)
    {
        pszLine = NULL;
    }

    return pszLine;
}


/**********************************************************************
 *                          AVCE00ReadNextLine()
 *
 * Returns the next line of the E00 representation of the coverage
 * or NULL when there are no more lines to generate, or if an error happened.
 * The returned line is a null-terminated string, and it does not
 * include a newline character.
 *
 * Call CPLGetLastErrorNo() after calling AVCE00ReadNextLine() to 
 * make sure that the line was generated succesfully.
 *
 * Note that AVCE00ReadNextLine() returns a reference to an
 * internal buffer whose contents will
 * be valid only until the next call to this function.  The caller should
 * not attempt to free() the returned pointer.
 **********************************************************************/
const char *AVCE00ReadNextLine(AVCE00ReadPtr psInfo)
{
    const char *pszLine = NULL;
    AVCE00Section *psSect;

    CPLErrorReset();

    /*-----------------------------------------------------------------
     * Check if we have finished generating E00 output
     *----------------------------------------------------------------*/
    if (psInfo->iCurSection >= psInfo->numSections)
        return NULL;

    psSect = &(psInfo->pasSections[psInfo->iCurSection]);

    /*-----------------------------------------------------------------
     * For simplicity, the generation of table output is in a separate
     * function.
     *----------------------------------------------------------------*/
    if (psSect->eType == AVCFileTABLE)
    {
        return _AVCE00ReadNextTableLine(psInfo);
    }

    if (psSect->eType == AVCFileUnknown)
    {
    /*-----------------------------------------------------------------
     * Section not attached to any file, used to hold header lines
     * or section separators, etc... just return the line directly and
     * move pointer to the next section.
     *----------------------------------------------------------------*/
        pszLine = psSect->pszName;
        if (psInfo->bReadAllSections)
            psInfo->iCurSection++;
        else
            psInfo->iCurSection = psInfo->numSections;
        psInfo->iCurStep = AVC_GEN_NOTSTARTED;
    }
    /*=================================================================
     *              ARC, PAL, CNT, LAB, TOL and TXT
     *================================================================*/
    else if (psInfo->iCurStep == AVC_GEN_NOTSTARTED &&
             (psSect->eType == AVCFileARC ||
              psSect->eType == AVCFilePAL ||
              psSect->eType == AVCFileRPL ||
              psSect->eType == AVCFileCNT ||
              psSect->eType == AVCFileLAB ||
              psSect->eType == AVCFileTOL ||
              psSect->eType == AVCFileTXT ||
              psSect->eType == AVCFileTX6 ||
              psSect->eType == AVCFileRXP   ) )
    {
    /*-----------------------------------------------------------------
     * Start processing of an ARC, PAL, CNT, LAB or TOL section:
     *   Open the file, get ready to read the first object from the 
     *   file, and return the header line.
     *  If the file fails to open then we will return NULL.
     *----------------------------------------------------------------*/
        psInfo->hFile = AVCBinReadOpen(psInfo->pszCoverPath, 
                                       psSect->pszFilename, 
                                       psInfo->eCoverType, psSect->eType,
                                       psInfo->psDBCSInfo);

        /*-------------------------------------------------------------
         * For some reason the file could not be opened... abort now.
         * An error message should have already been produced by 
         * AVCBinReadOpen()
         *------------------------------------------------------------*/
        if (psInfo->hFile == NULL)
            return NULL;

        pszLine = AVCE00GenStartSection(psInfo->hGenInfo, 
                                        psSect->eType, psSect->pszName);

        /*-------------------------------------------------------------
         * Reset the AVCE00GenInfo struct. so that it returns NULL,
         * which will force reading of the first object from the 
         * file on the next call to AVCE00ReadNextLine()
         *------------------------------------------------------------*/
        AVCE00GenReset(psInfo->hGenInfo);
        psInfo->iCurStep = AVC_GEN_DATA;
    }
    else if (psInfo->iCurStep == AVC_GEN_DATA &&
             (psSect->eType == AVCFileARC ||
              psSect->eType == AVCFilePAL ||
              psSect->eType == AVCFileRPL ||
              psSect->eType == AVCFileCNT ||
              psSect->eType == AVCFileLAB ||
              psSect->eType == AVCFileTOL ||
              psSect->eType == AVCFileTXT ||
              psSect->eType == AVCFileTX6 ||
              psSect->eType == AVCFileRXP    ) )
    {
    /*---------------