/* Program to copy FNOC Modal Height data from binary CD-ROM file */
/* to user's disc in ASCII or Binary for the specified range of */
/* records. NOTE: Integers assumed 4-byte length, short is 2-byte */
/* By: Peter W. Sloss */
/* NOAA/NGDC, Boulder, CO */

#include <stdio.h>

struct	in_record
	{
	short	longitude,latitude,modal_elev,max_elev,min_elev;
	char	ridges_tot,ridges_dir,primary_sfc,secondary_sfc;
	short	sfc_water,sfc_urban;
	};
float	Latitude,Longitude;
int		i,j,k,nskip,ncopy,maxbands;
long	offset,nbytes,bytes_read,bytes_written;
FILE	*IN,*OUT;
char	infile[80],outfile[32],outbuf[42],isASCII,Ok,copy_ok;
int		swap2();

main()
{
struct in_record FNOC;
printf("Enter FULL PATHNAME for FNOC.BIN;1 data file,\n");
/* next line gives Macintosh-style pathname */
/* for DOS PC, substitute CD drive letter, e.g., L:\ for */
/* "NGDC_RELIEF:", and backslashes (\) for rest of colons (:) */
printf("or @ for default (NGDC_RELIEF:TOPO:FNOC:FNOC.BIN;1)\n");
printf("Enter Path: ");
scanf("%s",infile);
if (infile[0] == '@') strcpy(infile,"NGDC_RELIEF:TOPO:FNOC:FNOC.BIN;1");
if (infile[0] == '@') strcpy(infile,"slossmac:FNOC.BIN");
if ((IN = fopen(infile,"rb"))==0)
						{
	printf("\nPlease check link to file %s\n",infile);
	printf("File not found. Sorry!\n");
	exit(1);			}
printf("Enter file name for OUTPUT data: ");
scanf("%s",outfile);
if ((OUT = fopen(outfile,"wb"))==0)	{
	printf("Error in opening output file\n");
	exit(1);			}
printf("Enter choice of ASCII or Binary output [a/b]: ");
scanf("%s",&isASCII);
if (isASCII != 'b' && isASCII != 'B') isASCII = 'a';
if (isASCII=='a') printf("Standard FNOC ASCII output format chosen\n");
	else printf("BINARY output chosen\n");
printf("Skip how many 5-degree bands? (<0 exits) ");
scanf("%d",&nskip);
maxbands = 36 - nskip;
if (nskip < 0 || nskip > 35) exit(1);
printf("Starting latitude = %d deg.\n",5*nskip-90);
printf("Copy how many 5-degree bands? (up to %d) ",maxbands);
scanf("%d",&ncopy);
if (ncopy > maxbands) ncopy = maxbands;
offset = 16200L*72*nskip;
nbytes = 16200L*72*ncopy;
if (isASCII = 'a')	{
printf("Display ASCII records being copied (y/n)? ");
scanf("%s",&Ok);
if (Ok=='Y') Ok = 'y';
					}
if (isASCII == 'a') nbytes = (nbytes/18)*40;
printf("Copied data will occupy %ld bytes on disc. Continue? (y/n) ",
	nbytes);
scanf("%s",&copy_ok);
if (copy_ok != 'y' && copy_ok != 'Y') exit(1);
bytes_read = 0;
while (bytes_read < nbytes)	{
j = fseek(IN,offset,0);
i = fread(&FNOC,18,1,IN);
/* swap bytes in short integers for Macintosh, Sun, Amiga, and other */
/* computers which have high-byte first, comment out for DOS/VAX */
swap2(&(FNOC.latitude));
swap2(&(FNOC.longitude));
swap2(&(FNOC.modal_elev));
swap2(&(FNOC.max_elev));
swap2(&(FNOC.min_elev));
swap2(&(FNOC.sfc_water));
swap2(&(FNOC.sfc_urban));
Latitude = (float)(FNOC.latitude)/100.0;
Longitude = (float)(FNOC.longitude)/100.0;
offset += 18;
bytes_read += 18;
if (isASCII != 'a')	{
	fwrite(&FNOC,18,1,OUT);
	bytes_written += 18;
			}
else			{
	sprintf(&outbuf[0],
	"%7.2f %6.2f %3d %3d %3d %2d%2d%2d%2d%3d%3d",
		Longitude,Latitude,FNOC.modal_elev,FNOC.max_elev,FNOC.min_elev,
		(int)(FNOC.ridges_tot),(int)(FNOC.ridges_dir),
		(int)(FNOC.primary_sfc),(int)(FNOC.secondary_sfc),
		FNOC.sfc_water,FNOC.sfc_urban);
	fwrite(outbuf,40,1,OUT);
if (Ok == 'y') printf("%s\n",outbuf);
	bytes_written += 40;
			}
	fseek(OUT,bytes_written,0);
				}
printf("%ld bytes written. Done.\n",bytes_written);
}

swap2(word) unsigned char word[2];
{
unsigned char tmp;
tmp = word[1];
word[1] = word[0];
word[0] = tmp;
}