apt-pkg/contrib/hashsum.cc

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