src/gromacs/fileio/xdrd.cpp

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  37 #include "gmxpre.h"
  38
  39 #include "gromacs/fileio/xdrf.h"
  40 #include "gromacs/math/vectypes.h"
  41 #include "gromacs/utility/fatalerror.h"
  42 #include "gromacs/utility/smalloc.h"
  43
  44 int xdr_real(XDR* xdrs, real* r)
  45 {
  46 #if GMX_DOUBLE
  47     float f;
  48     int   ret;
  49
  50     f   = *r;
  51     ret = xdr_float(xdrs, &f);
  52     *r  = f;
  53
  54     return ret;
  55 #else
  56     return xdr_float(xdrs, static_cast<float*>(r));
  57 #endif
  58 }
  59
  60 int xdr3drcoord(XDR* xdrs, real* fp, int* size, real* precision)
  61 {
  62 #if GMX_DOUBLE
  63     float* ffp;
  64     float  fprec;
  65     int    i, ret, isize;
  66
  67     isize = *size * DIM;
  68     if (isize <= 0)
  69     {
  70         gmx_fatal(FARGS, "Don't know what to malloc for ffp, isize = %d", isize);
  71     }
  72
  73     snew(ffp, isize);
  74
  75     for (i = 0; (i < isize); i++)
  76     {
  77         ffp[i] = fp[i];
  78     }
  79     fprec = *precision;
  80     ret   = xdr3dfcoord(xdrs, ffp, size, &fprec);
  81
  82     *precision = fprec;
  83     for (i = 0; (i < isize); i++)
  84     {
  85         fp[i] = ffp[i];
  86     }
  87
  88     sfree(ffp);
  89     return ret;
  90 #else
  91     return xdr3dfcoord(xdrs, reinterpret_cast<float*>(fp), size, reinterpret_cast<float*>(precision));
  92 #endif
  93 }
  94
  95 int xdr_int32(XDR* xdrs, int32_t* i)
  96 {
  97     // Note that this implementation assumes that an int is at least
  98     // 32 bits, which is not strictly required by the language, but
  99     // good enough in practice on 32- or 64-bit systems. GROMACS
 100     // requires 64-bit systems.
 101     static_assert(sizeof(int) >= 4, "XDR handling assumes that an int32_t can be stored in an int");
 102     int temporary = static_cast<int>(*i);
 103     int ret       = xdr_int(xdrs, &temporary);
 104     *i            = static_cast<int32_t>(temporary);
 105
 106     return ret;
 107 }
 108
 109 int xdr_int64(XDR* xdrs, int64_t* i)
 110 {
 111     // Note that this implementation assumes that an int is at least
 112     // 32 bits, which is not strictly required by the language, but
 113     // good enough in practice on 32- or 64-bit systems. GROMACS
 114     // requires 64-bit systems.
 115     static_assert(2 * sizeof(int) >= 8,
 116                   "XDR handling assumes that an int64_t can be stored in two ints");
 117
 118     static const uint64_t two_p32_m1 = 0xFFFFFFFF;
 119
 120     uint64_t imaj64 = ((*i) >> 32) & two_p32_m1;
 121     uint64_t imin64 = (*i) & two_p32_m1;
 122     int      imaj   = static_cast<int>(imaj64);
 123     int      imin   = static_cast<int>(imin64);
 124     int      ret    = xdr_int(xdrs, &imaj);
 125     ret |= xdr_int(xdrs, &imin);
 126
 127     *i = ((static_cast<uint64_t>(imaj) << 32) | (static_cast<uint64_t>(imin) & two_p32_m1));
 128
 129     return ret;
 130 }