tabview.cpp

linux下一款GIS程序源码

// tabview.cpp: implementation of the TABView class.
//
//////////////////////////////////////////////////////////////////////

#include "tabview.h"

#include "ugk_errhandle.h"
#include "ugk_memopr.h"
#include "ugk_string.h"



/**********************************************************************
 *                   TABView::TABView()
 *
 * Constructor.
 **********************************************************************/
TABView::TABView()
{
    m_pszFname = NULL;
    m_eAccessMode = TABRead;
    m_papszTABFile = NULL;
    m_pszVersion = NULL;
    m_pszCharset = NULL;

    m_numTABFiles = 0;
    m_papszTABFnames = NULL;
    m_papoTABFiles = NULL;
    m_nMainTableIndex = -1;

    m_papszFieldNames = NULL;
    m_papszWhereClause = NULL;

    m_poRelation = NULL;
    m_bRelFieldsCreated = FALSE;
}

/**********************************************************************
 *                   TABView::~TABView()
 *
 * Destructor.
 **********************************************************************/
TABView::~TABView()
{
    Close();
}



int TABView::GetFeatureCount (int bForce)
{

    if (m_nMainTableIndex != -1)
        return m_papoTABFiles[m_nMainTableIndex]->GetFeatureCount( bForce );

    return 0;
}

void TABView::ResetReading()
{
    if (m_nMainTableIndex != -1)
        m_papoTABFiles[m_nMainTableIndex]->ResetReading();
}



/**********************************************************************
 *                   TABView::Open()
 *
 * Open a .TAB dataset and the associated files, and initialize the 
 * structures to be ready to read features from it.
 *
 * This class is used to open .TAB files that define a view on
 * two other .TAB files.  Regular .TAB datasets should be opened using
 * the TABFile class instead.
 *
 * Set bTestOpenNoError=TRUE to silently return -1 with no error message
 * if the file cannot be opened.  This is intended to be used in the
 * context of a TestOpen() function.  The default value is FALSE which
 * means that an error is reported if the file cannot be opened.
 *
 * Returns 0 on success, -1 on error.
 **********************************************************************/
int TABView::Open(const char *pszFname, const char *pszAccess,
                  UGKBool bTestOpenNoError /*= FALSE*/ )
{
    char nStatus = 0;
   
    if (m_numTABFiles > 0)
    {
        UGKError(ET_Failure, UGKErr_AssertionFailed,
                 "Open() failed: object already contains an open file");
        return -1;
    }

    /*-----------------------------------------------------------------
     * Validate access mode and call the right open method
     *----------------------------------------------------------------*/
    if (EQUALN(pszAccess, "r", 1))
    {
        m_eAccessMode = TABRead;
        nStatus = OpenForRead(pszFname, bTestOpenNoError);
    }
    else if (EQUALN(pszAccess, "w", 1))
    {
        m_eAccessMode = TABWrite;
        nStatus = OpenForWrite(pszFname);
    }
    else
    {
        UGKError(ET_Failure, UGKErr_NotSupported,
                  "Open() failed: access mode \"%s\" not supported", pszAccess);
        return -1;
    }

    return nStatus;
}




/**********************************************************************
 *                   TABView::OpenForRead()
 *
 * Open for reading
 *
 * Returns 0 on success, -1 on error.
 **********************************************************************/
int TABView::OpenForRead(const char *pszFname, 
                         UGKBool bTestOpenNoError /*= FALSE*/ )
{
    char *pszPath = NULL;
    int nFnameLen = 0;
   
    m_eAccessMode = TABRead;

    /*-----------------------------------------------------------------
     * Read main .TAB (text) file
     *----------------------------------------------------------------*/
    m_pszFname = UGKStrdup(pszFname);

#ifndef WIN32APP
    /*-----------------------------------------------------------------
     * On Unix, make sure extension uses the right cases
     * We do it even for write access because if a file with the same
     * extension already exists we want to overwrite it.
     *----------------------------------------------------------------*/
    TABAdjustFilenameExtension(m_pszFname);
#endif

    /*-----------------------------------------------------------------
     * Open .TAB file... since it's a small text file, we will just load
     * it as a stringlist in memory.
     *----------------------------------------------------------------*/
    m_papszTABFile = LoadFileToList(m_pszFname);
    if (m_papszTABFile == NULL)
    {
        if (!bTestOpenNoError)
        {
            UGKError(ET_Failure, UGKErr_FileIO,
                      "Failed opening %s.", m_pszFname);
        }
        
        UGK_Free(m_pszFname);
        return -1;
    }

    /*-------------------------------------------------------------
     * Look for a line with the "create view" keyword.
     * If there is no "create view", then we may have a valid .TAB file,
     * but we do not support it in this class.
     *------------------------------------------------------------*/
    UGKBool bCreateViewFound = FALSE;
    for (int i=0; 
         !bCreateViewFound && m_papszTABFile && m_papszTABFile[i];
         i++)
    {
        const char *pszStr = m_papszTABFile[i];
        while(*pszStr != '\0' && isspace(*pszStr))
            pszStr++;
        if (EQUALN(pszStr, "create view", 11))
            bCreateViewFound = TRUE;
    }

    if ( !bCreateViewFound )
    {
       if (!bTestOpenNoError)
            UGKError(ET_Failure, UGKErr_NotSupported,
                     "%s contains no table view definition.  "
                     "This type of .TAB file cannot be read by this library.",
                     m_pszFname);
        else
            UGKErrorReset();

        UGK_Free(m_pszFname);

        return -1;
    }

    /*-----------------------------------------------------------------
     * OK, this appears to be a valid TAB view dataset...
     * Extract the path component from the main .TAB filename
     * to build the filename of the sub-tables
     *----------------------------------------------------------------*/
    pszPath = UGKStrdup(m_pszFname);
    nFnameLen = strlen(pszPath);
    for( ; nFnameLen > 0; nFnameLen--)
    {
        if (pszPath[nFnameLen-1] == '/' || 
            pszPath[nFnameLen-1] == '\\' )
        {
            break;
        }
        pszPath[nFnameLen-1] = '\0';
    }

    /*-----------------------------------------------------------------
     * Extract the useful info from the TAB header
     *----------------------------------------------------------------*/
    if (ParseTABFile(pszPath, bTestOpenNoError) != 0)
    {
        // Failed parsing... an error has already been produced if necessary
        UGK_Free(pszPath);
        Close();
        return -1;
    }
    UGK_Free(pszPath);
    pszPath = NULL;

    /*-----------------------------------------------------------------
     * __TODO__ For now, we support only 2 files linked through a single
     *          field... so we'll do some validation first to make sure
     *          that what we found in the header respects these limitations.
     *----------------------------------------------------------------*/
    if (m_numTABFiles != 2)
    {
        if (!bTestOpenNoError)
            UGKError(ET_Failure, UGKErr_NotSupported,
                    "Open Failed: Dataset %s defines a view on %d tables. "
                     "This is not currently supported.",
                     m_pszFname, m_numTABFiles);
        Close();
        return -1;
    }

    /*-----------------------------------------------------------------
     * Open all the tab files listed in the view
     *----------------------------------------------------------------*/
    m_papoTABFiles = (TABFile**)UGK_Calloc(m_numTABFiles, sizeof(TABFile*));

    for (int iFile=0; iFile < m_numTABFiles; iFile++)
    {
#ifndef WIN32APP
        TABAdjustFilenameExtension(m_papszTABFnames[iFile]);
#endif
        
        m_papoTABFiles[iFile] = new TABFile;
   
        if ( m_papoTABFiles[iFile]->Open(m_papszTABFnames[iFile],
                                         "rb", bTestOpenNoError) != 0)
        {
            // Open Failed... an error has already been reported, just return.
            if (bTestOpenNoError)
                UGKErrorReset();
            Close();
            return -1;
        }
    }

    /*-----------------------------------------------------------------
     * Create TABRelation... this will build FeatureDefn, etc.
     * __TODO__ For now this assumes only 2 tables in the view...
     *----------------------------------------------------------------*/
    m_poRelation = new TABRelation;
    
    assert(m_nMainTableIndex == 0);
    assert(CountOfList(m_papszWhereClause) == 5);
    char *pszTableName = TABGetBasename(m_pszFname);
    if ( m_poRelation->Init(pszTableName,
                            m_papoTABFiles[0], m_papoTABFiles[1],
                            m_papszWhereClause[4], m_papszWhereClause[2],
                            m_papszFieldNames)  != 0 )
    {
        // An error should already have been reported
        UGK_Free(pszTableName);
        Close();
        return -1;
    }
    UGK_Free(pszTableName);

    return 0;
}


/**********************************************************************
 *                   TABView::OpenForWrite()
 *
 * Create a new TABView dataset
 *
 * Returns 0 on success, -1 on error.
 **********************************************************************/
int TABView::OpenForWrite(const char *pszFname)
{
    int nFnameLen = 0;
   
    m_eAccessMode = TABWrite;

    /*-----------------------------------------------------------------
     * Read main .TAB (text) file
     *----------------------------------------------------------------*/
    m_pszFname = UGKStrdup(pszFname);

#ifndef WIN32APP
    /*-----------------------------------------------------------------
     * On Unix, make sure extension uses the right cases
     * We do it even for write access because if a file with the same
     * extension already exists we want to overwrite it.
     *----------------------------------------------------------------*/
    TABAdjustFilenameExtension(m_pszFname);
#endif

    /*-----------------------------------------------------------------
     * Extract the path component from the main .TAB filename
     *----------------------------------------------------------------*/
    char *pszPath = UGKStrdup(m_pszFname);
    nFnameLen = strlen(pszPath);
    for( ; nFnameLen > 0; nFnameLen--)
    {
        if (pszPath[nFnameLen-1] == '/' || 
            pszPath[nFnameLen-1] == '\\' )
        {
            break;
        }
        pszPath[nFnameLen-1] = '\0';
    }

    char *pszBasename = TABGetBasename(m_pszFname);

    /*-----------------------------------------------------------------
     * Create the 2 TAB files for the view.
     *
     * __TODO__ For now, we support only 2 files linked through a single
     *          field... not sure if anything else than that can be useful
     *          anyways.
     *----------------------------------------------------------------*/
    m_numTABFiles = 2;
    m_papszTABFnames = NULL;
    m_nMainTableIndex = 0;
    m_bRelFieldsCreated = FALSE;

    m_papoTABFiles = (TABFile**)UGK_Calloc(m_numTABFiles, sizeof(TABFile*));

    for (int iFile=0; iFile < m_numTABFiles; iFile++)
    {
        m_papszTABFnames = AppendPrintf(m_papszTABFnames, "%s%s%d.tab", 
                                               pszPath, pszBasename, iFile+1);
#ifndef WIN32APP
        TABAdjustFilenameExtension(m_papszTABFnames[iFile]);
#endif
        
        m_papoTABFiles[iFile] = new TABFile;
   
        if ( m_papoTABFiles[iFile]->Open(m_papszTABFnames[iFile], "wb") != 0)
        {
            // Open Failed... an error has already been reported, just return.
            UGK_Free(pszPath);
            UGK_Free(pszBasename);
            Close();
            return -1;
        }
    }