Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Purpose:  Implementation of the Open() function.
       4             :  *
       5             :  ******************************************************************************
       6             :  * Copyright (c) 2009
       7             :  * PCI Geomatics, 90 Allstate Parkway, Markham, Ontario, Canada.
       8             :  *
       9             :  * Permission is hereby granted, free of charge, to any person obtaining a
      10             :  * copy of this software and associated documentation files (the "Software"),
      11             :  * to deal in the Software without restriction, including without limitation
      12             :  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
      13             :  * and/or sell copies of the Software, and to permit persons to whom the
      14             :  * Software is furnished to do so, subject to the following conditions:
      15             :  *
      16             :  * The above copyright notice and this permission notice shall be included
      17             :  * in all copies or substantial portions of the Software.
      18             :  *
      19             :  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
      20             :  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      21             :  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
      22             :  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      23             :  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
      24             :  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
      25             :  * DEALINGS IN THE SOFTWARE.
      26             :  ****************************************************************************/
      27             : #include "pcidsk.h"
      28             : #include "pcidsk_config.h"
      29             : #include "pcidsk_types.h"
      30             : #include "pcidsk_file.h"
      31             : #include "pcidsk_interfaces.h"
      32             : #include "core/cpcidskfile.h"
      33             : #include <string>
      34             : #include <cstring>
      35             : #include <cassert>
      36             : 
      37             : using namespace PCIDSK;
      38             : 
      39             : /************************************************************************/
      40             : /*                                Open()                                */
      41             : /************************************************************************/
      42             : 
      43             : /**
      44             :  * Open a PCIDSK (.pix) file.
      45             :  *
      46             :  * This function attempts to open the named file, with the indicated
      47             :  * access and the provided set of system interface methods.
      48             :  *
      49             :  * @param filename the name of the PCIDSK file to access.
      50             :  * @param access either "r" for read-only, or "r+" for read-write access.
      51             :  * @param interfaces Either NULL to use default interfaces, or a pointer
      52             :  * to a populated interfaces object.
      53             :  *
      54             :  * @return a pointer to a file object for accessing the PCIDSK file.
      55             :  */
      56             : 
      57         256 : PCIDSKFile *PCIDSK::Open( const std::string& filename, const std::string& access,
      58             :                           const PCIDSKInterfaces *interfaces,
      59             :                           int max_channel_count )
      60             : 
      61             : {
      62             : /* -------------------------------------------------------------------- */
      63             : /*      Use default interfaces if none are passed in.                   */
      64             : /* -------------------------------------------------------------------- */
      65         256 :     PCIDSKInterfaces default_interfaces;
      66         256 :     if( interfaces == nullptr )
      67           0 :         interfaces = &default_interfaces;
      68             : 
      69             : /* -------------------------------------------------------------------- */
      70             : /*      First open the file, and confirm that it is PCIDSK before       */
      71             : /*      going further.                                                  */
      72             : /* -------------------------------------------------------------------- */
      73         256 :     void *io_handle = interfaces->io->Open( filename, access );
      74             : 
      75         256 :     assert( io_handle != nullptr );
      76             : 
      77             :     char header_check[6];
      78             : 
      79         256 :     if( interfaces->io->Read( header_check, 1, 6, io_handle ) != 6
      80         256 :         || memcmp(header_check,"PCIDSK",6) != 0 )
      81             :     {
      82           1 :         interfaces->io->Close( io_handle );
      83           1 :         return (PCIDSKFile*)ThrowPCIDSKExceptionPtr( "File %s does not appear to be PCIDSK format.",
      84           0 :                               filename.c_str() );
      85             :     }
      86             : 
      87             : /* -------------------------------------------------------------------- */
      88             : /*      Create the PCIDSKFile object.                                   */
      89             : /* -------------------------------------------------------------------- */
      90             : 
      91         255 :     CPCIDSKFile *file = new CPCIDSKFile( filename );
      92             : 
      93         255 :     file->interfaces = *interfaces;
      94         255 :     file->io_handle = io_handle;
      95         255 :     file->io_mutex = interfaces->CreateMutex();
      96             : 
      97         255 :     if( strstr(access.c_str(),"+") != nullptr )
      98         124 :         file->updatable = true;
      99             : 
     100             : /* -------------------------------------------------------------------- */
     101             : /*      Initialize it from the header.                                  */
     102             : /* -------------------------------------------------------------------- */
     103             :     try
     104             :     {
     105         255 :         file->InitializeFromHeader(max_channel_count);
     106             :     }
     107           2 :     catch(...)
     108             :     {
     109           1 :         delete file;
     110           1 :         throw;
     111             :     }
     112             : 
     113         254 :     return file;
     114             : }