apt-pkg/contrib/hashsum.cc

   1 // Cryptographic API Base
   2
   3 #include <unistd.h>
   4 #include "hashsum_template.h"
   5
   6 // Summation::AddFD - Add content of file into the checksum             /*{{{*/
   7 // ---------------------------------------------------------------------
   8 /* */
   9 bool SummationImplementation::AddFD(int const Fd, unsigned long Size) {
  10    unsigned char Buf[64 * 64];
  11    int Res = 0;
  12    int ToEOF = (Size == 0);
  13    unsigned long n = sizeof(Buf);
  14    if (!ToEOF)
  15       n = std::min(Size, n);
  16    while (Size != 0 || ToEOF)
  17    {
  18       Res = read(Fd, Buf, n);
  19       if (Res < 0 || (!ToEOF && (unsigned) Res != n)) // error, or short read
  20          return false;
  21       if (ToEOF && Res == 0) // EOF
  22          break;
  23       Size -= Res;
  24       Add(Buf,Res);
  25    }
  26    return true;
  27 }
  28                                                                         /*}}}*/