/****** do_data.c
Processes the actual input data stream (the compressed data) and
writes out the decompressed data. The output file is padded with
NULLs out to a multiple of 2880 bytes.
Modified 3/29/90 by AW3 to preserve input buffer length sent to
decomp - fixes bug when carrying over pixels from one read to the
next
******/
#define NULL 0
#define TRUE 'T'
#define FALSE 'F'
#define FITS_SIZE 2880
#define TEXT_SIZE 80
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <io.h>
/* External stuff from dec.c -- used everywhere */
extern char inbfr[], /* the file input buffer */
_end[]; /* the end-of-header buffer */
extern void decomp( char *, long int *, short int *, short int *,
long int *) ;
#ifndef min
#define min(a,b) (((a) < (b)) ? (a) : (b))
#endif
void do_data(FILE *infile, FILE *outfile, long *file_len)
{
long total_read, /* Total number of data bytes read */
total_left, /* Number of bytes left to be read */
total_written, /* Number of data bytes written out */
bytlen, /* Number of bytes fed to decomp */
num_decomp, /* Number of pixels from decomp */
n_left, /* Number of "hanging" bytes from decomp */
onepercent, /* used for printing status */
j, /* used for printing status */
n_rec; /* Number of FITS records to read */
int ipixel, /* Starting pixel from decomp */
n_read, /* Number of bytes read into inbfr */
rec_counter, /* loop counter */
num_written, /* Number of bytes written out */
read_in, /* Number of bytes to read at a time */
in_len, /* Length of input going to DECOMP */
*temp_buffer; /* decompression buffer */
/* Allocate space to the decompression buffer */
temp_buffer = (int *)malloc(3000 * sizeof(int) );
/* Initialize a bunch of stuff */
read_in = FITS_SIZE;
total_left = *file_len;
onepercent = total_left / 100;
/* Calculate number of FITS records to read in */
n_rec = total_left / read_in;
if ( (total_left % read_in) != 0) n_rec++;
total_read = 0L;
n_left = 0L;
num_decomp = 0L;
total_written = 0L;
j = 1;
ipixel = 0;
/* Let 'em know we're alive, and have parsed the extension header */
printf("Compressed file length= %ld bytes\n\n",*file_len);
printf("File decompression started......\n\n");
printf("Percent Decompressed:\n\n");
/* Work our way through the data, decompressing as we go */
for (rec_counter = 0; rec_counter < n_rec; rec_counter++)
{
memset( &inbfr[n_left], NULL, FITS_SIZE); /* blank the input */
/* Read the data at offset n_left to preserve left-over bytes */
n_read = fread( &inbfr[n_left], sizeof(char), read_in, infile);
total_read = total_read + (long)n_read;
/*
Tell decomp how many bytes to work on, watching for the end
of the data, then do the decompression.
*/
in_len = (long)min( (long)n_read, total_left) + n_left;
bytlen = in_len ; /* save this guy since decomp will change it */
decomp( inbfr, &bytlen, &ipixel, temp_buffer, &num_decomp);
n_left = (long)n_read + n_left - bytlen; /* anything left over? */
/* write out whatever is decompressed and update total */
num_written = fwrite( temp_buffer, sizeof(int), num_decomp, outfile);
/* Keep track of total bytes written */
total_written = total_written + (long)(num_written * 2);
total_left = total_left - n_read;
/* set up for next call - save left-over bytes, if any */
if (n_left == 1)
inbfr[0] = inbfr[in_len - n_left];
if (n_left == 2)
{
inbfr[0] = inbfr[in_len - n_left];
inbfr[1] = inbfr[in_len - n_left + 1];
}
/* keep track of % decompressed as we go along */
if (total_read >= (j * onepercent) )
{
printf("%7d",j);
j++;
if((j % 10) == 1) printf("\n");
}
}
/* pad the file with nulls out to a multiple of 2880 bytes */
num_decomp = FITS_SIZE - ( total_written % FITS_SIZE);
memset( temp_buffer, NULL, num_decomp );
num_written = fwrite( temp_buffer, sizeof(char), num_decomp, outfile);
free( temp_buffer );
}