/*
 * @project      The CERN Tape Archive (CTA)
 * @copyright    Copyright © 1990-2022 CERN
 * @license      This program is free software, distributed under the terms of the GNU General Public
 *               Licence version 3 (GPL Version 3), copied verbatim in the file "COPYING". You can
 *               redistribute it and/or modify it under the terms of the GPL Version 3, or (at your
 *               option) any later version.
 *
 *               This program is distributed in the hope that it will be useful, but WITHOUT ANY
 *               WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 *               PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 *               In applying this licence, CERN does not waive the privileges and immunities
 *               granted to it by virtue of its status as an Intergovernmental Organization or
 *               submit itself to any jurisdiction.
 */

/* readc.c              Fortran callable C I/O functions                */

/*
 * C functions called by Fortran READ -
 *
 * stream:	stream identifier.
 * buff  :	buffer address
 * count :	On entry, size of the buffer
 *		On exit, the number of bytes actually transferred.
 * status:	Status of the read.
 *
 *
 * read_s() called to read files with control words.
 * read_d() called to read files without control words.
 *
 */

#include <stdio.h>
#include <sys/types.h>
#include <osdep.h>

void read_s_(FILE **stream,
             char *  buff,
             int  * count,
             int * status)
{
	int rcode ;
        int size ;

	/*
 	 * Initialization
	 */
	*status= 0 ;

	/*
 	 * Reading the record length.
	 */
	rcode= fread(&size,sizeof(size),1,*stream) ;
	if ( rcode == 0 ) {
		/*
		 * End of file.
		 */
		*count = 0 ;
		*status= 2 ;
		return ;
	}

	else if ( rcode != 1 ) {
		/*
		 * Error.
		 */
		*status= 5 ;
		return ;
	}
	/*
	 * Reading the record.
	 */
        if ( *count > size ) {
                rcode= fread(buff,size,1,*stream) ;
		if ( rcode != 1 ) {
			*status= 5 ;
			return ;
		}
		/*
		 * Number of bytes read.
		 */
		*count= size ;
	}
	else {
    rcode= fread(buff,*count,1,*stream) ;
		if ( rcode != 1 ) {
			*status= 5 ;
			return ;
		}
	}


	/*
	 * Skipping the record's end if it
	 * was only partially read.
	 */
	if ( *count < size ) {

		*status= -1 ;
		if ( fseek(*stream,size-(*count),1) == -1 ) {
			*status= 5 ;
			return ;
		}
	}

	/*
	 * Reading the trailing record length.
	 */
	rcode= fread(&size,sizeof(size),1,*stream) ;
	if ( rcode != 1 ) {
		*status= 5 ;
		return ;
	}

}
void read_d_(FILE **stream,
             char *  buff,
             int  * count,
             int * status)
{
	int rcode ;

 	/*
	 * Initialization.
	 */
	*status= 0 ;

	/*
	 * Reading the record.
	 */
	rcode= fread(buff,*count,1,*stream) ;
	if ( rcode == 0 ) {
		/*
		 * End of file.
		 */
		*count = 0 ;
		*status= 2 ;
		return ;
	}

	else if ( rcode < 0 || rcode != 1 ) {
		/*
		 * Error
		 */
		*status= 5 ;
		return ;
	}

}