file.h

/*
 * file - file I/O routines callable by users
 *
 * Copyright (C) 1999-2007,2014,2021,2023  David I. Bell and Landon Curt Noll
 *
 * Primary author:  David I. Bell
 *
 * Calc is open software; you can redistribute it and/or modify it under
 * the terms of the version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * Calc 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 Lesser General
 * Public License for more details.
 *
 * A copy of version 2.1 of the GNU Lesser General Public License is
 * distributed with calc under the filename COPYING-LGPL.  You should have
 * received a copy with calc; if not, write to Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Under source code control:   1996/05/24 05:55:58
 * File existed as early as:    1996
 *
 * chongo <was here> /\oo/\     http://www.isthe.com/chongo/
 * Share and enjoy!  :-)        http://www.isthe.com/chongo/tech/comp/calc/
 */


#if !defined(INCLUDE_FILE_H)
#define INCLUDE_FILE_H


#if defined(CALC_SRC)   /* if we are building from the calc source tree */
# include "have_fgetsetpos.h"
#else
# include <calc/have_fgetsetpos.h>
#endif


/*
 * Definition of opened files.
 */
#define MODE_LEN (sizeof("rb+")-1)
typedef struct {
        FILEID id;              /* id to identify this file */
        FILE *fp;               /* real file structure for I/O */
        dev_t dev;              /* file device */
        ino_t inode;            /* file inode */
        char *name;             /* file name */
        bool reading;           /* true if opened for reading */
        bool writing;           /* true if opened for writing */
        bool appending;         /* true if also opened for appending */
        bool binary;            /* true if binary mode - mode ignored/unused */
        char action;            /* most recent use for 'r', 'w' or 0 */
        char mode[MODE_LEN+1];  /* open mode */
} FILEIO;


/*
 * fgetpos/fsetpos vs fseek/ftell interface
 *
 * f_seek_set(FILE *stream, FILEPOS *loc)
 *      Seek loc bytes from the beginning of the open file, stream.
 *
 * f_tell(FILE *stream, FILEPOS *loc)
 *      Set loc to bytes from the beginning of the open file, stream.
 *
 * We assume that if your system does not have fgetpos/fsetpos,
 * then it will have a FILEPOS that is a scalar type (e.g., long).
 * Some obscure systems without fgetpos/fsetpos may not have a simple
 * scalar type.  In these cases the f_tell macro below will fail.
 */
#if defined(HAVE_FGETSETPOS)

#define f_seek_set(stream, loc) fsetpos((FILE*)(stream), (FILEPOS*)(loc))
#define f_tell(stream, loc) fgetpos((FILE*)(stream), (FILEPOS*)(loc))

#else

#define f_seek_set(stream, loc)  \
        fseek((FILE*)(stream), *(FILEPOS*)(loc), SEEK_SET)
#define f_tell(stream, loc) (*((FILEPOS*)(loc)) = ftell((FILE*)(stream)))

#endif


/*
 * external functions
 */
E_FUNC FILEIO * findid(FILEID id, int writable);
E_FUNC int fgetposid(FILEID id, FILEPOS *ptr);
E_FUNC int fsetposid(FILEID id, FILEPOS *ptr);
E_FUNC int get_open_siz(FILE *fp, ZVALUE *res);
E_FUNC char* findfname(FILEID);
E_FUNC FILE *f_pathopen(char *name, char *mode, char *pathlist,
                        char **openpath);


#endif /* !INCLUDE_FILE_H */