/*
$Header: d:/cvsroot/tads/TADS2/FIO.H,v 1.3 1999/07/11 00:46:29 MJRoberts Exp $
*/

/* 
 *   Copyright (c) 1992, 2002 Michael J. Roberts.  All Rights Reserved.
 *   
 *   Please see the accompanying license file, LICENSE.TXT, for information
 *   on using and copying this software.  
 */
/*
Name
  fio.h - file i/o interface
Function
  fiel i/o functions - write game, read game, save game, restore game
Notes
  none
Modified
  04/02/92 MJRoberts     - creation
*/

#ifndef FIO_INCLUDED
#define FIO_INCLUDED

#ifndef MCM_INCLUDED
#include "mcm.h"
#endif
#ifndef OS_INCLUDED
#include "os.h"
#endif
#ifndef OBJ_INCLUDED
#include "obj.h"
#endif
#ifndef TOK_INCLUDED
#include "tok.h"
#endif

/* forward declarations */
struct voccxdef;


/* load-on-demand context (passed in by mcm in load callback) */
typedef struct fiolcxdef fiolcxdef;
struct fiolcxdef
{
    osfildef *fiolcxfp;                        /* file pointer of load file */
    errcxdef *fiolcxerr;                          /* error handling context */
    ulong     fiolcxst;                          /* starting offset in file */
    uint      fiolcxflg;                   /* flags from original load file */
    uint      fiolcxseed;                                    /* fioxor seed */
    uint      fiolcxinc;                                /* fioxor increment */
};

/* write game to binary file */
void fiowrt(struct mcmcxdef *mctx, struct voccxdef *vctx,
            struct tokcxdef *tokctx, struct tokthdef *tab,
            uchar *fmts, uint fmtl, char *fname, uint flags, objnum preinit,
            int extc, uint prpcnt, char *filever);

/* flag values for use with fiowrt */
#define FIOFSYM   0x01               /* include symbol table in output file */
#define FIOFLIN   0x02          /* include source file tracking information */
#define FIOFPRE   0x04        /* preinit needs to be run after reading game */
#define FIOFCRYPT 0x08           /* "encrypt" objects prior to writing them */
#define FIOFBIN   0x10                        /* writing precompiled header */
#define FIOFFAST  0x20                     /* fast-load records are in file */
#define FIOFCASE  0x40    /* case folding was turned on in original compile */
#define FIOFLIN2  0x80                            /* new-style line records */

/* read game from binary file; sets up loader callback context */
void fiord(struct mcmcxdef *mctx, struct voccxdef *vctx,
           struct tokcxdef *tctx,
           char *fname, char *exename,
           struct fiolcxdef *setupctx, objnum *preinit, uint *flagp,
           struct tokpdef *path, uchar **fmtsp, uint *fmtlp,
           uint *pcntptr, int flags, struct appctxdef *appctx,
           char *argv0);

/* shut down load-on-demand subsystem, close load file */
void fiorcls(fiolcxdef *ctx);

/* loader callback - load an object on demand */
void OS_LOADDS fioldobj(void *ctx, mclhd handle, uchar *ptr,
                        ushort siz);

/* 
 *   Save a game - returns TRUE on failure.  We'll save the file to
 *   'fname'.  'game_fname' is the name of the game file; if this is not
 *   null, we'll save it to the saved game file so that the player can
 *   later start the game by specifying only the saved game file to the
 *   run-time.  'game_fname' can be null, in which case we'll omit the
 *   game file information.  
 */
int fiosav(struct voccxdef *vctx, char *fname, char *game_fname);

/*
 *   fiorso() result codes 
 */
#define FIORSO_SUCCESS          0                                /* success */
#define FIORSO_FILE_NOT_FOUND   1                         /* file not found */
#define FIORSO_NOT_SAVE_FILE    2                  /* not a saved game file */
#define FIORSO_BAD_FMT_VSN      3       /* incompatible file format version */
#define FIORSO_BAD_GAME_VSN     4  /* file saved by another game or version */
#define FIORSO_READ_ERROR       5            /* error reading from the file */
#define FIORSO_NO_PARAM_FILE    6   /* no parameter file (for restore(nil)) */


/* restore a game - returns TRUE on failure */
int fiorso(struct voccxdef *vctx, char *fname);

/*
 *   Look in a saved game file to determine if it has information on which
 *   GAM file created it.  If the GAM file information is available, this
 *   routine returns true and stores the game file name in the given
 *   buffer; if the information isn't available, we'll return false.  
 */
int fiorso_getgame(char *saved_file, char *buf, size_t buflen);

/* encrypt/decrypt an object */
void fioxor(uchar *p, uint siz, uint seed, uint inc);


/* strings stored in binary game file for identification and validation */

/* file header string */
#define FIOFILHDR    "TADS2 bin\012\015\032"

/* resource file header string */
#define FIOFILHDRRSC "TADS2 rsc\012\015\032"

/* CURRENT file format version string */
#define FIOVSNHDR  "v2.2.0"

/* other file format versions that can be READ by this version */
#define FIOVSNHDR2 "v2.0.0"
#define FIOVSNHDR3 "v2.0.1"

#endif /* FIO_INCLUDED */