netcdf-c/nc_test/tst_cdf5_begin.c

/*! \file

Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014,
2015, 2016, 2017, 2018
University Corporation for Atmospheric Research/Unidata.

See \ref copyright file for more info.

*/

#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <netcdf.h>

/* When using NetCDF 4.4.1 ad prior to create a CDF-5 file and defining a small
 * variable after a big variable (> 2^32-3 bytes), the file starting offset of
 * the small variable (and all variables defined after the big variable) is
 * calculated incorrectly. This test program detects this bug by checking the
 * contents of the possible overlaps between the two variables.
 */

#define ERR {if(err!=NC_NOERR){printf("Error at line %d in %s: %s\n", __LINE__,__FILE__, nc_strerror(err));nerrs++;}}

#define FILE_NAME "tst_cdf5_begin.nc"

int main(int argc, char *argv[])
{
    int i, err, nerrs=0, ncid, dimid[2], varid[2];
    short buf[10];
    size_t start, count;

    err = nc_create(FILE_NAME, NC_CLOBBER|NC_64BIT_DATA, &ncid); ERR;
    err = nc_def_dim(ncid, "dim0", NC_MAX_UINT, &dimid[0]); ERR
    err = nc_def_dim(ncid, "dim1", 10,          &dimid[1]); ERR

    /* define one small variable after one big variable */
    err = nc_def_var(ncid, "var_big",   NC_SHORT, 1, &dimid[0], &varid[0]); ERR
    err = nc_def_var(ncid, "var_small", NC_SHORT, 1, &dimid[1], &varid[1]); ERR
    err = nc_set_fill(ncid, NC_NOFILL, NULL); ERR
    err = nc_enddef(ncid); ERR

    /* write to var_big in location overlapping with var_small when using
     * netCDF 4.4.x or prior */
    start = NC_MAX_UINT/sizeof(short);
    count = 10;
    for (i=0; i<10; i++) buf[i] = i;
    err = nc_put_vara_short(ncid, varid[0], &start, &count, buf); ERR

    /* write var_small */
    for (i=0; i<10; i++) buf[i] = -1;
    err = nc_put_var_short(ncid, varid[1], buf); ERR

    /* read back var_big and check contents */
    for (i=0; i<10; i++) buf[i] = -1;
    err = nc_get_vara_short(ncid, varid[0], &start, &count,buf); ERR
    for (i=0; i<10; i++) {
        if (buf[i] != i) {
            printf("Error at buf[%d] expect %d but got %hd\n",i,i,buf[i]);
            nerrs++;
        }
    }
    err = nc_close(ncid); ERR

    return (nerrs > 0);
}