source: trunk/WRF.COMMON/WRFV3/external/io_grib1/WGRIB/wrtieee.c @ 3532

#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include "grib.h"


/* wesley ebisuzaki v1.3
 *
 * write ieee file -- big endian format
 *
 * input float *array           data to be written
 *       int n                  size of array
 *       int header             1 for f77 style header 0 for none
 *                              (header is 4 byte header
 *       FILE *output           output file
 *
 * v1.2 7/97 buffered, faster
 * v1.3 2/99 fixed (typo) error in wrtieee_header found by
 *     Bob Farquhar
 */

#define BSIZ 1024*4

int wrtieee(float *array, int n, int header, FILE *output) {

        unsigned long int l;
        int i, nbuf;
        unsigned char buff[BSIZ];
        unsigned char h4[4];

        nbuf = 0;
        if (header) {
                l = n * 4;
                for (i = 0; i < 4; i++) {
                        h4[i] = l & 255;
                        l >>= 8;
                }
                buff[nbuf++] = h4[3];
                buff[nbuf++] = h4[2];
                buff[nbuf++] = h4[1];
                buff[nbuf++] = h4[0];
        }
        for (i = 0; i < n; i++) {
                if (nbuf >= BSIZ) {
                    fwrite(buff, 1, BSIZ, output);
                    nbuf = 0;
                }
                flt2ieee(array[i], buff + nbuf);
                nbuf += 4;
        }
        if (header) {
                if (nbuf == BSIZ) {
                    fwrite(buff, 1, BSIZ, output);
                    nbuf = 0;
                }
                buff[nbuf++] = h4[3];
                buff[nbuf++] = h4[2];
                buff[nbuf++] = h4[1];
                buff[nbuf++] = h4[0];
        }
        if (nbuf) fwrite(buff, 1, nbuf, output);
        return 0;
}

/* write a big-endian 4 byte integer .. f77 IEEE  header */

int wrtieee_header(unsigned int n, FILE *output) {
        unsigned h4[4];

        h4[0] = n & 255;
        h4[1] = (n >> 8) & 255;
        h4[2] = (n >> 16) & 255;
        h4[3] = (n >> 24) & 255;

        putc(h4[3],output);
        putc(h4[2],output);
        putc(h4[1],output);
        putc(h4[0],output);

        return 0;
}