Line data    Source code

       1             : /*******************************************************************************
       2             :  *  Project: libopencad
       3             :  *  Purpose: OpenSource CAD formats support library
       4             :  *  Author: Alexandr Borzykh, mush3d at gmail.com
       5             :  *  Author: Dmitry Baryshnikov, bishop.dev@gmail.com
       6             :  *  Language: C++
       7             :  *******************************************************************************
       8             :  *  The MIT License (MIT)
       9             :  *
      10             :  *  Copyright (c) 2016 Alexandr Borzykh
      11             :  *  Copyright (c) 2016 NextGIS, <info@nextgis.com>
      12             :  *
      13             :  *  Permission is hereby granted, free of charge, to any person obtaining a copy
      14             :  *  of this software and associated documentation files (the "Software"), to deal
      15             :  *  in the Software without restriction, including without limitation the rights
      16             :  *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
      17             :  *  copies of the Software, and to permit persons to whom the Software is
      18             :  *  furnished to do so, subject to the following conditions:
      19             :  *
      20             :  *  The above copyright notice and this permission notice shall be included in all
      21             :  *  copies or substantial portions of the Software.
      22             :  *
      23             :  *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
      24             :  *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      25             :  *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
      26             :  *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      27             :  *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
      28             :  *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
      29             :  *  SOFTWARE.
      30             :  *******************************************************************************/
      31             : #ifndef DWG_IO_H
      32             : #define DWG_IO_H
      33             : 
      34             : #include "cadheader.h"
      35             : #include "cadobjects.h"
      36             : 
      37             : #include <string>
      38             : #include <algorithm>
      39             : 
      40             : /* DATA TYPES CONSTANTS */
      41             : 
      42             : #define BITSHORT_NORMAL         0x0
      43             : #define BITSHORT_UNSIGNED_CHAR  0x1
      44             : #define BITSHORT_ZERO_VALUE     0x2
      45             : #define BITSHORT_256            0x3
      46             : 
      47             : #define BITLONG_NORMAL          0x0
      48             : #define BITLONG_UNSIGNED_CHAR   0x1
      49             : #define BITLONG_ZERO_VALUE      0x2
      50             : #define BITLONG_NOT_USED        0x3
      51             : 
      52             : #define BITDOUBLE_NORMAL        0x0
      53             : #define BITDOUBLE_ONE_VALUE     0x1
      54             : #define BITDOUBLE_ZERO_VALUE    0x2
      55             : #define BITDOUBLE_NOT_USED      0x3
      56             : 
      57             : #define BITDOUBLEWD_DEFAULT_VALUE  0x0
      58             : #define BITDOUBLEWD_4BYTES_PATCHED 0x1
      59             : #define BITDOUBLEWD_6BYTES_PATCHED 0x2
      60             : #define BITDOUBLEWD_FULL_RD        0x3
      61             : 
      62             : #if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
      63             : #define CAD_MSB
      64             : #endif
      65             : 
      66             : namespace DWGConstants {
      67             : extern const size_t SentinelLength;
      68             : extern const char * HeaderVariablesStart;
      69             : extern const char * HeaderVariablesEnd;
      70             : extern const char * DSClassesStart;
      71             : extern const char * DSClassesEnd;
      72             : 
      73             : /* UNUSED
      74             : static const char * DWGDSPreviewStart
      75             :             = "\x1F\x25\x6D\x07\xD4\x36\x28\x28\x9D\x57\xCA\x3F\x9D\x44\x10\x2B";
      76             : static const char * DWGDSPreviewEnd
      77             :             = "\xE0\xDA\x92\xF8\x2B\xc9\xD7\xD7\x62\xA8\x35\xC0\x62\xBB\xEF\xD4";
      78             : 
      79             : static const char * DWGSecondFileHeaderStart
      80             :             = "\xD4\x7B\x21\xCE\x28\x93\x9F\xBF\x53\x24\x40\x09\x12\x3C\xAA\x01";
      81             : static const char * DWGSecondFileHeaderEnd
      82             :             = "\x2B\x84\xDE\x31\xD7\x6C\x60\x40\xAC\xDB\xBF\xF6\xED\xC3\x55\xFE";
      83             : */
      84             : }
      85             : 
      86             : // TODO: probably it would be better to have no dependencies on <algorithm>.
      87             : template<typename T, typename S>
      88         450 : inline void SwapEndianness( T&& object, S size )
      89             : {
      90         450 :     std::reverse( reinterpret_cast<char*>(&object),
      91             :                   reinterpret_cast<char*>(&object) + size );
      92         450 : }
      93             : 
      94             : #ifdef CAD_MSB
      95             : template<typename T>
      96             : inline void FromLSB( T&& object )
      97             : {
      98             :     SwapEndianness(object, sizeof(T));
      99             : }
     100             : #else
     101             : template<typename T>
     102        1186 : inline void FromLSB( T&& )
     103             : {
     104        1186 : }
     105             : #endif
     106             : 
     107             : /*
     108             :  * Method taken from here: http://stackoverflow.com/a/2611850
     109             :  * Purpose: no C++14 dependencies in library
     110             :  */
     111             : template< unsigned long N >
     112             : struct bin
     113             : {
     114             :     enum
     115             :     {
     116             :         value = ( N % 8 ) + ( bin< N / 8 >::value << 1 )
     117             :     };
     118             : };
     119             : 
     120             : template<>
     121             : struct bin< 0 >
     122             : {
     123             :     enum
     124             :     {
     125             :         value = 0
     126             :     };
     127             : };
     128             : #define binary( n ) bin<0##n>::value
     129             : 
     130             : extern const int DWGCRC8Table[256];
     131             : 
     132             : unsigned short CalculateCRC8(unsigned short initialVal, const char *ptr, int num );
     133             : 
     134             : class CADBuffer
     135             : {
     136             : public:
     137             :     enum SeekPosition {
     138             :         BEG = 1,
     139             :         CURRENT,
     140             :         END
     141             :     };
     142             : 
     143             : public:
     144             :     explicit CADBuffer(size_t size);
     145             :     ~CADBuffer();
     146             : 
     147             :     // Disable copy
     148             :     CADBuffer(const CADBuffer&) = delete;
     149             :     CADBuffer& operator=(const CADBuffer&) = delete;
     150             : 
     151             :     void WriteRAW(const void* data, size_t size);
     152         679 :     void* GetRawBuffer() const { return m_pBuffer + m_nBitOffsetFromStart / 8; }
     153             :     unsigned char Read2B();
     154             :     unsigned char Read3B();
     155             :     unsigned char Read4B();
     156             : 
     157             :     double ReadBITDOUBLE();
     158             :     void SkipBITDOUBLE();
     159             : 
     160             :     int ReadRAWLONG();
     161             :     short ReadRAWSHORT();
     162             :     double ReadRAWDOUBLE();
     163             :     CADHandle ReadHANDLE();
     164             :     CADHandle ReadHANDLE8BLENGTH();
     165             :     void SkipHANDLE();
     166             :     bool ReadBIT();
     167             :     void SkipBIT();
     168             :     unsigned char ReadCHAR();
     169             :     short ReadBITSHORT();
     170             :     int ReadBITLONG();
     171             :     double ReadBITDOUBLEWD(double defaultvalue);
     172             :     long ReadMCHAR();
     173             :     long ReadUMCHAR();
     174             :     unsigned int ReadMSHORT();
     175             :     std::string ReadTV();
     176             :     void SkipTV();
     177             :     void SkipBITLONG();
     178             :     void SkipBITSHORT();
     179             :     CADVector ReadVector();
     180             :     CADVector ReadRAWVector();
     181             : 
     182             :     void Seek(size_t offset, enum SeekPosition position = SeekPosition::CURRENT);
     183        2167 :     size_t PositionBit() const { return m_nBitOffsetFromStart; }
     184        3427 :     bool IsEOB() const { return m_bEOB; }
     185             : 
     186             : private:
     187             :     char* m_pBuffer;
     188             :     size_t m_nBitOffsetFromStart;
     189             :     size_t m_nSize;
     190             :     bool m_bEOB = false;
     191             : };
     192             : 
     193             : // long ReadRAWLONGLONG( const char * pabyInput, size_t& nBitOffsetFromStart);
     194             : 
     195             : 
     196             : #endif // DWG_IO_H