avc_e00read.c

用于读取TAB、MIF、SHP文件的类

/**********************************************************************
 * $Id: avc_e00read.c,v 1.21 2006/06/27 18:38:43 dmorissette Exp $
 *
 * Name:     avc_e00read.c
 * Project:  Arc/Info vector coverage (AVC)  BIN->E00 conversion library
 * Language: ANSI C
 * Purpose:  Functions to open a binary coverage and read it as if it
 *           was an ASCII E00 file.  This file is the main entry point
 *           for the library.
 * Author:   Daniel Morissette, [e-mail]
 *
 **********************************************************************
 * Copyright (c) 1999-2005, Daniel Morissette
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
 * DEALINGS IN THE SOFTWARE.
 **********************************************************************
 *
 * $Log: avc_e00read.c,v $
 * Revision 1.21  2006/06/27 18:38:43  dmorissette
 * Cleaned up E00 reading (bug 1497, patch from James F.)
 *
 * Revision 1.20  2006/06/27 18:06:34  dmorissette
 * Applied patch for EOP processing from James F. (bug 1497)
 *
 * Revision 1.19  2006/06/16 11:48:11  daniel
 * New functions to read E00 files directly as opposed to translating to
 * binary coverage. Used in the implementation of E00 read support in OGR.
 * Contributed by James E. Flemer. (bug 1497)
 *
 * Revision 1.18  2006/06/14 16:31:28  daniel
 * Added support for AVCCoverPC2 type (bug 1491)
 *
 * Revision 1.17  2005/06/03 03:49:58  daniel
 * Update email address, website url, and copyright dates
 *
 * Revision 1.16  2004/07/14 18:49:50  daniel
 * Fixed leak when trying to open something that's not a coverage (bug513)
 *
 * Revision 1.15  2002/08/27 15:46:15  daniel
 * Applied fix made in GDAL/OGR by 'aubin' (moved include ctype.h after avc.h)
 *
 * Revision 1.14  2000/09/22 19:45:21  daniel
 * Switch to MIT-style license
 *
 * Revision 1.13  2000/05/29 15:31:31  daniel
 * Added Japanese DBCS support
 *
 * Revision 1.12  2000/02/14 17:21:01  daniel
 * Made more robust for corrupted or invalid files in cover directory
 *
 * Revision 1.11  2000/02/02 04:26:04  daniel
 * Support reading TX6/TX7/RXP/RPL files in weird coverages
 *
 * Revision 1.10  2000/01/10 02:56:30  daniel
 * Added read support for "weird" coverages
 *
 * Revision 1.9  2000/01/07 07:12:49  daniel
 * Added support for reading PC Coverage TXT files
 *
 * Revision 1.8  1999/12/24 07:41:08  daniel
 * Check fname length before testing for extension in AVCE00ReadFindCoverType()
 *
 * Revision 1.7  1999/12/24 07:18:34  daniel
 * Added PC Arc/Info coverages support
 *
 * Revision 1.6  1999/08/26 17:22:18  daniel
 * Use VSIFopen() instead of fopen() directly
 *
 * Revision 1.5  1999/08/23 18:21:41  daniel
 * New syntax for AVCBinReadListTables()
 *
 * Revision 1.4  1999/05/11 02:10:01  daniel
 * Free psInfo struct inside AVCE00ReadClose()
 *
 * Revision 1.3  1999/04/06 19:43:26  daniel
 * Added E00 coverage path in EXP 0  header line
 *
 * Revision 1.2  1999/02/25 04:19:01  daniel
 * Added TXT, TX6/TX7, RXP and RPL support + other minor changes
 *
 * Revision 1.1  1999/01/29 16:28:52  daniel
 * Initial revision
 *
 **********************************************************************/

#ifdef WIN32
#  include <direct.h>   /* getcwd() */
#endif

#include "avc.h"

#include <ctype.h>      /* toupper() */

static void _AVCE00ReadScanE00(AVCE00ReadE00Ptr psRead);
static int _AVCE00ReadBuildSqueleton(AVCE00ReadPtr psInfo,
                                     char **papszCoverDir);
static AVCCoverType _AVCE00ReadFindCoverType(char **papszCoverDir);


/**********************************************************************
 *                          AVCE00ReadOpen()
 *
 * Open a Arc/Info coverage to read it as if it was an E00 file.
 *
 * You can either pass the name of the coverage directory, or the path
 * to one of the files in the coverage directory.  The name of the
 * coverage MUST be included in pszCoverPath... this means that
 * passing "." is invalid.
 * The following are all valid values for pszCoverPath:
 *               /home/data/country
 *               /home/data/country/
 *               /home/data/country/arc.adf
 * (Of course you should replace the '/' with '\\' on DOS systems!)
 *
 * Returns a new AVCE00ReadPtr handle or NULL if the coverage could 
 * not be opened or if it does not appear to be a valid Arc/Info coverage.
 *
 * The handle will eventually have to be released with AVCE00ReadClose().
 **********************************************************************/
AVCE00ReadPtr  AVCE00ReadOpen(const char *pszCoverPath)
{
    AVCE00ReadPtr   psInfo;
    int             i, nLen, nCoverPrecision;
    VSIStatBuf      sStatBuf;
    char            **papszCoverDir = NULL;

    CPLErrorReset();

    /*-----------------------------------------------------------------
     * pszCoverPath must be either a valid directory name or a valid
     * file name.
     *----------------------------------------------------------------*/
    if (pszCoverPath == NULL || strlen(pszCoverPath) == 0 ||
        VSIStat(pszCoverPath, &sStatBuf) == -1)
    {
        CPLError(CE_Failure, CPLE_OpenFailed, 
                 "Invalid coverage path: %s.", 
                 pszCoverPath?pszCoverPath:"(NULL)");
        return NULL;
    }

    /*-----------------------------------------------------------------
     * Alloc the AVCE00ReadPtr handle
     *----------------------------------------------------------------*/
    psInfo = (AVCE00ReadPtr)CPLCalloc(1, sizeof(struct AVCE00ReadInfo_t));

    /*-----------------------------------------------------------------
     * 2 possibilities about the value passed in pszCoverPath:
     * - It can be the directory name of the coverage
     * - or it can be the path to one of the files in the coverage
     *
     * If the name passed in pszCoverPath is not a directory, then we
     * need to strip the last part of the filename to keep only the
     * path, terminated by a '/' (or a '\\').
     *----------------------------------------------------------------*/
    if (VSI_ISDIR(sStatBuf.st_mode))
    {
        /*-------------------------------------------------------------
         * OK, we have a valid directory name... make sure it is 
         * terminated with a '/' (or '\\')
         *------------------------------------------------------------*/
        nLen = strlen(pszCoverPath);

        if (pszCoverPath[nLen-1] == '/' || pszCoverPath[nLen-1] == '\\')
            psInfo->pszCoverPath = CPLStrdup(pszCoverPath);
        else
        {
#ifdef WIN32
            psInfo->pszCoverPath = CPLStrdup(CPLSPrintf("%s\\",pszCoverPath));
#else
            psInfo->pszCoverPath = CPLStrdup(CPLSPrintf("%s/",pszCoverPath));
#endif
        }
    }
    else
    {
        /*-------------------------------------------------------------
         * We are dealing with a filename.
         * Extract the coverage path component and store it.
         * The coverage path will remain terminated by a '/' or '\\' char.
         *------------------------------------------------------------*/
        psInfo->pszCoverPath = CPLStrdup(pszCoverPath);

        for( i = strlen(psInfo->pszCoverPath)-1; 
             i > 0 && psInfo->pszCoverPath[i] != '/' &&
                 psInfo->pszCoverPath[i] != '\\';
             i-- ) {}

        psInfo->pszCoverPath[i+1] = '\0';
    }


    /*-----------------------------------------------------------------
     * Extract the coverage name from the coverage path.  Note that
     * for this the coverage path must be in the form:
     * "dir1/dir2/dir3/covername/" ... if it is not the case, then
     * we would have to use getcwd() to find the current directory name...
     * but for now we'll just produce an error if this happens.
     *----------------------------------------------------------------*/
    nLen = 0;
    for( i = strlen(psInfo->pszCoverPath)-1; 
	 i > 0 && psInfo->pszCoverPath[i-1] != '/' &&
	          psInfo->pszCoverPath[i-1] != '\\'&&
	          psInfo->pszCoverPath[i-1] != ':';
	 i-- ) 
    {
        nLen++;
    }

    if (nLen > 0)
    {
        psInfo->pszCoverName = CPLStrdup(psInfo->pszCoverPath+i);
        psInfo->pszCoverName[nLen] = '\0';
    }
    else
    {
        CPLError(CE_Failure, CPLE_OpenFailed, 
                 "Invalid coverage path (%s): "
                 "coverage name must be included in path.", pszCoverPath);

        CPLFree(psInfo->pszCoverPath);
        CPLFree(psInfo);
        return NULL;
    }

    /*-----------------------------------------------------------------
     * Read the coverage directory listing and try to establish the cover type
     *----------------------------------------------------------------*/
    papszCoverDir = CPLReadDir(psInfo->pszCoverPath);

    psInfo->eCoverType = _AVCE00ReadFindCoverType(papszCoverDir);

    if (psInfo->eCoverType == AVCCoverTypeUnknown  )
    {
        CPLError(CE_Failure, CPLE_OpenFailed, 
                 "Invalid coverage (%s): directory does not appear to "
                 "contain any supported vector coverage file.",  pszCoverPath);
        CPLFree(psInfo->pszCoverName);
        CPLFree(psInfo->pszCoverPath);
        CPLFree(psInfo->pszInfoPath);
        CPLFree(psInfo);
        CSLDestroy(papszCoverDir);
        return NULL;
    }

   
    /*-----------------------------------------------------------------
     * INFO path: PC Coverages have all files in the same dir, and unix
     * covers have the INFO files in ../info
     *----------------------------------------------------------------*/
    if (psInfo->eCoverType == AVCCoverPC || psInfo->eCoverType == AVCCoverPC2)
    {
        psInfo->pszInfoPath = CPLStrdup(psInfo->pszCoverPath);
    }
    else
    {
        /*-------------------------------------------------------------
         * Lazy way to build the INFO path: simply add "../info/"...
         * this could probably be improved!
         *------------------------------------------------------------*/
        psInfo->pszInfoPath =(char*)CPLMalloc((strlen(psInfo->pszCoverPath)+9)*
                                           sizeof(char));
#ifdef WIN32
#  define AVC_INFOPATH "..\\info\\"
#else
#  define AVC_INFOPATH "../info/"
#endif
        sprintf(psInfo->pszInfoPath, "%s%s", psInfo->pszCoverPath, 
                                             AVC_INFOPATH);

        AVCAdjustCaseSensitiveFilename(psInfo->pszInfoPath);
    }

    /*-----------------------------------------------------------------
     * For Unix coverages, check that the info directory exists and 
     * contains the "arc.dir".  In AVCCoverWeird, the arc.dir is 
     * called "../INFO/ARCDR9".
     * PC Coverages have their info tables in the same direcotry as 
     * the coverage files.
     *----------------------------------------------------------------*/
    if ((psInfo->eCoverType == AVCCoverV7 &&
         ! AVCFileExists(psInfo->pszInfoPath, "arc.dir") ) ||
         (psInfo->eCoverType == AVCCoverWeird &&
         ! AVCFileExists(psInfo->pszInfoPath, "arcdr9") ) )
    {
        CPLError(CE_Failure, CPLE_OpenFailed, 
             "Invalid coverage (%s): 'info' directory not found or invalid.", 
                                              pszCoverPath);
        CPLFree(psInfo->pszCoverName);
        CPLFree(psInfo->pszCoverPath);
        CPLFree(psInfo->pszInfoPath);
        CPLFree(psInfo);
        CSLDestroy(papszCoverDir);
        return NULL;
    }

    /*-----------------------------------------------------------------
     * Make sure there was no error until now before we build squeleton.
     *----------------------------------------------------------------*/
    if (CPLGetLastErrorNo() != 0)
    {
        CPLFree(psInfo->pszCoverName);
        CPLFree(psInfo->pszCoverPath);
        CPLFree(psInfo->pszInfoPath);
        CPLFree(psInfo);
        CSLDestroy(papszCoverDir);
        return NULL;
    }

    /*-----------------------------------------------------------------
     * Build the E00 file squeleton and be ready to return a E00 header...
     * We'll also read the coverage precision by the same way.