src/gmxlib/xtcio.c

   1 /*
   2  * $Id$
   3  *
   4  *       This source code is part of
   5  *
   6  *        G   R   O   M   A   C   S
   7  *
   8  * GROningen MAchine for Chemical Simulations
   9  *
  10  *               VERSION 2.0
  11  *
  12  * Copyright (c) 1991-1999
  13  * BIOSON Research Institute, Dept. of Biophysical Chemistry
  14  * University of Groningen, The Netherlands
  15  *
  16  * Please refer to:
  17  * GROMACS: A message-passing parallel molecular dynamics implementation
  18  * H.J.C. Berendsen, D. van der Spoel and R. van Drunen
  19  * Comp. Phys. Comm. 91, 43-56 (1995)
  20  *
  21  * Also check out our WWW page:
  22  * http://md.chem.rug.nl/~gmx
  23  * or e-mail to:
  24  * gromacs@chem.rug.nl
  25  *
  26  * And Hey:
  27  * Green Red Orange Magenta Azure Cyan Skyblue
  28  */
  29 static char *SRCID_xtcio_c = "$Id$";
  30
  31 #include <string.h>
  32 #include "typedefs.h"
  33 #include "xdrf.h"
  34 #include "gmxfio.h"
  35 #include "xtcio.h"
  36 #include "smalloc.h"
  37 #include "vec.h"
  38 #include "futil.h"
  39 #include "fatal.h"
  40
  41 #define XTC_MAGIC 1995
  42
  43 int open_xtc(char *fn,char *mode)
  44 {
  45   return fio_open(fn,mode);
  46 }
  47
  48 void close_xtc(int fp)
  49 {
  50   fio_close(fp);
  51 }
  52
  53 static void check_xtc_magic(int magic)
  54 {
  55   if (magic != XTC_MAGIC)
  56     fatal_error(0,"Magic Number Error in XTC file (read %d, should be %d)",
  57                 magic,XTC_MAGIC);
  58 }
  59
  60 int xtc_check(char *str,bool bResult,char *file,int line)
  61 {
  62   if (!bResult) {
  63     if (debug)
  64       fprintf(debug,"\nXTC error: read/write of %s failed, "
  65               "source file %s, line %d\n",str,file,line);
  66     return 0;
  67   }
  68   return 1;
  69 }
  70
  71 void xtc_check_fat_err(char *str,bool bResult,char *file,int line)
  72 {
  73   if (!bResult) {
  74     fatal_error(0,"XTC read/write of %s failed, "
  75                 "source file %s, line %d\n",str,file,line);
  76   }
  77 }
  78
  79 static int xtc_header(XDR *xd,int *magic,int *natoms,int *step,real *time,
  80                       bool *bOK)
  81 {
  82   int result;
  83
  84   if (xdr_int(xd,magic) == 0)
  85     return 0;
  86   result=XTC_CHECK("natoms", xdr_int(xd,natoms));  /* number of atoms */
  87   if (result)
  88     result=XTC_CHECK("step",   xdr_int(xd,step));    /* frame number    */
  89   if (result)
  90     result=XTC_CHECK("time",   xdr_real(xd,time));   /* time            */
  91   *bOK=(result!=0);
  92
  93   return result;
  94 }
  95
  96 static int xtc_coord(XDR *xd,int *natoms,matrix box,rvec *x,real *prec)
  97 {
  98   int i,j,result;
  99
 100   /* box */
 101   result=1;
 102   for(i=0; ((i<DIM) && result); i++)
 103     for(j=0; ((j<DIM) && result); j++)
 104       result=XTC_CHECK("box",xdr_real(xd,&(box[i][j])));
 105
 106   if (result)
 107     /* coordinates     */
 108     result=XTC_CHECK("x",xdr3drcoord(xd,x[0],natoms,prec));
 109
 110   return result;
 111 }
 112
 113 static int xtc_io(XDR *xd,int *magic,
 114                   int *natoms,int *step,real *time,
 115                   matrix box,rvec *x,real *prec,bool *bOK)
 116 {
 117   if (!xtc_header(xd,magic,natoms,step,time,bOK))
 118     return 0;
 119   return xtc_coord(xd,natoms,box,x,prec);
 120 }
 121
 122 int write_xtc(int fp,
 123               int natoms,int step,real time,
 124               matrix box,rvec *x,real prec)
 125 {
 126   int magic_number = XTC_MAGIC;
 127   XDR *xd;
 128   bool bDum;
 129
 130   xd = fio_getxdr(fp);
 131   /* write magic number and xtc identidier */
 132   if (!xtc_header(xd,&magic_number,&natoms,&step,&time,&bDum))
 133     return 0;
 134
 135   /* write data */
 136   return xtc_coord(xd,&natoms,box,x,&prec);
 137 }
 138
 139 int read_first_xtc(int fp,int *natoms,int *step,real *time,
 140                    matrix box,rvec **x,real *prec,bool *bOK)
 141 {
 142   int magic;
 143   XDR *xd;
 144
 145   *bOK=TRUE;
 146   xd = fio_getxdr(fp);
 147
 148   /* read header and malloc x */
 149   if ( !xtc_header(xd,&magic,natoms,step,time,bOK))
 150     return 0;
 151
 152   /* Check magic number */
 153   check_xtc_magic(magic);
 154
 155   snew(*x,*natoms);
 156
 157   *bOK=xtc_coord(xd,natoms,box,*x,prec);
 158
 159   return *bOK;
 160 }
 161
 162 int read_next_xtc(int fp,
 163                   int *natoms,int *step,real *time,
 164                   matrix box,rvec *x,real *prec,bool *bOK)
 165 {
 166   int magic;
 167   XDR *xd;
 168
 169   *bOK=TRUE;
 170   xd = fio_getxdr(fp);
 171
 172   /* read header */
 173   if (!xtc_header(xd,&magic,natoms,step,time,bOK))
 174     return 0;
 175
 176   /* Check magic number */
 177   check_xtc_magic(magic);
 178
 179   *bOK=xtc_coord(xd,natoms,box,x,prec);
 180
 181   return *bOK;
 182 }
 183