online_distribution/newbasic/ogzBuffer.cc

0001
0002 #include "ogzBuffer.h"
0003 #include "BufferConstants.h"
0004
0005
0006 // the constructor first ----------------
0007 #ifndef WIN32
0008 ogzBuffer::ogzBuffer (int fdin, PHDWORD * where,
0009               const int length,
0010               const int level,
0011               const int irun,
0012               const int iseq):
0013   ophBuffer(fdin,where,length,irun,iseq)
0014 #else
0015 ogzBuffer::ogzBuffer (const char *fpp, PHDWORD * where,
0016               const int length,
0017                       int & status,
0018               const int level,
0019               const int irun,
0020               const int iseq):
0021   ophBuffer(fpp,where,length,status,irun,iseq)
0022 #endif
0023 {
0024   // get a buffer for zlib
0025
0026   compressionlevel = level;
0027   outputarraylength = (int)(length *1.1) + 2048;
0028   outputarray = new PHDWORD[outputarraylength];
0029
0030 }
0031
0032 // ----------------------------------------------------------
0033 // returns the number of bytes written, including record wasted space.
0034 //
0035 int ogzBuffer::writeout()
0036 {
0037   if (! dirty) return 0;
0038
0039   if (! has_end) addEoB();
0040
0041   uLongf outputlength_in_bytes = outputarraylength*4;
0042   uLong bytes_to_be_written = bptr->Length;
0043
0044   compress2 ( (Bytef*) &outputarray[4], &outputlength_in_bytes, (Bytef*) bptr,
0045         bytes_to_be_written, compressionlevel);
0046
0047   outputarray[0] = outputlength_in_bytes +4*BUFFERHEADERLENGTH;
0048   outputarray[1] = GZBUFFERMARKER; // -518;
0049   outputarray[2] = bptr->Bufseq;
0050   outputarray[3] = bptr->Length;
0051
0052   unsigned int ip =0;
0053   char *cp = (char *) outputarray;
0054
0055   while (ip<outputarray[0])
0056     {
0057       int n = write ( fd, cp, BUFFERBLOCKSIZE);
0058       if ( n != BUFFERBLOCKSIZE)
0059         {
0060           std::cout << " could not write output, bytes written: " << n << std::endl;
0061           return 0;
0062         }
0063       cp += BUFFERBLOCKSIZE;
0064       ip += BUFFERBLOCKSIZE;
0065     }
0066   dirty = 0;
0067   byteswritten += ip;
0068   return 0;
0069 }
0070
0071
0072 // ----------------------------------------------------------
0073 ogzBuffer::~ogzBuffer()
0074 {
0075   writeout();
0076   delete [] outputarray;
0077
0078 }
0079