/*
 * This file is part of the UCB release of Plan 9. It is subject to the license
 * terms in the LICENSE file found in the top-level directory of this
 * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
 * part of the UCB release of Plan 9, including this file, may be copied,
 * modified, propagated, or distributed except according to the terms contained
 * in the LICENSE file.
 */

#pragma	src	"/sys/src/lib/bio"
#pragma	lib	"libbio.a"

typedef	struct	Biobuf	Biobuf;
typedef	struct	Biobufhdr	Biobufhdr;

enum
{
	Bsize		= 8*1024,
	Bungetsize	= UTFmax+1,	/* space for ungetc */
	Bmagic		= 0x314159,
	Beof		= -1,
	Bbad		= -2,

	Binactive	= 0,		/* states */
	Bractive,
	Bwactive,
	Bracteof,
};

struct	Biobufhdr
{
	int	icount;		/* neg num of bytes at eob */
	int	ocount;		/* num of bytes at bob */
	int	rdline;		/* num of bytes after rdline */
	int	runesize;	/* num of bytes of last getrune */
	int	state;		/* r/w/inactive */
	int	fid;		/* open file */
	int	flag;		/* magic if malloc'ed */
	int64_t	offset;		/* offset of buffer in file */
	int	bsize;		/* size of buffer */
	uint8_t*	bbuf;		/* pointer to beginning of buffer */
	uint8_t*	ebuf;		/* pointer to end of buffer */
	uint8_t*	gbuf;		/* pointer to good data in buf */
};

struct	Biobuf
{
	Biobufhdr;
	uint8_t	b[Bungetsize+Bsize];
};

/* Dregs, redefined as functions for backwards compatibility */
#define	BGETC(bp)	Bgetc(bp)
#define	BPUTC(bp,c)	Bputc(bp,c)
#define	BOFFSET(bp)	Boffset(bp)
#define	BLINELEN(bp)	Blinelen(bp)
#define	BFILDES(bp)	Bfildes(bp)

int	Bbuffered(Biobufhdr*);
int	Bfildes(Biobufhdr*);
int	Bflush(Biobufhdr*);
int	Bgetc(Biobufhdr*);
int	Bgetd(Biobufhdr*, double*);
int32_t	Bgetrune(Biobufhdr*);
int	Binit(Biobuf*, int, int);
int	Binits(Biobufhdr*, int, int, uint8_t*, int);
int	Blinelen(Biobufhdr*);
int64_t	Boffset(Biobufhdr*);
Biobuf*	Bopen(char*, int);
Biobuf*	Bfdopen(int, int);
int	Bprint(Biobufhdr*, char*, ...);
int	Bvprint(Biobufhdr*, char*, va_list);
int	Bputc(Biobufhdr*, int);
int	Bputrune(Biobufhdr*, int32_t);
void*	Brdline(Biobufhdr*, int);
char*	Brdstr(Biobufhdr*, int, int);
int32_t	Bread(Biobufhdr*, void*, int32_t);
int64_t	Bseek(Biobufhdr*, int64_t, int);
int	Bterm(Biobufhdr*);
int	Bungetc(Biobufhdr*);
int	Bungetrune(Biobufhdr*);
int32_t	Bwrite(Biobufhdr*, void*, int32_t);

#pragma	varargck	argpos	Bprint	2