/*
 * @(#)context.h	3.7 4/24/85
 */

/*
 * Copyright (c) 1983 Regents of the University of California,
 * All rights reserved.  Redistribution permitted subject to
 * the terms of the Berkeley Software License Agreement.
 */

#include <stdio.h>

struct context {
	struct context *x_link;		/* nested contexts */
	char x_type;			/* tag for union */
	union {
		struct {	/* input is a file */
			char *X_filename;	/* input file name */
			FILE *X_fp;		/* input stream */
			short X_lineno;		/* current line number */
			char X_bol;		/* at beginning of line */
			char X_noerr;		/* don't report errors */
			struct ww *X_errwin;	/* error window */
		} x_f;
		struct {	/* input is a buffer */
			char *X_buf;		/* input buffer */
			char *X_bufp;		/* current position in buf */
			struct value *X_arg;	/* argument for alias */
			int X_narg;		/* number of arguments */
		} x_b;
	} x_un;
		/* holding place for current token */
	int x_token;			/* the token */
	struct value x_val;		/* values associated with token */
		/* parser error flags */
	unsigned x_erred :1;		/* had an error */
	unsigned x_synerred :1;		/* had syntax error */
	unsigned x_abort :1;		/* fatal error */
};
#define x_buf		x_un.x_b.X_buf
#define x_bufp		x_un.x_b.X_bufp
#define x_arg		x_un.x_b.X_arg
#define x_narg		x_un.x_b.X_narg
#define x_filename	x_un.x_f.X_filename
#define x_fp		x_un.x_f.X_fp
#define x_lineno	x_un.x_f.X_lineno
#define x_bol		x_un.x_f.X_bol
#define x_errwin	x_un.x_f.X_errwin
#define x_noerr		x_un.x_f.X_noerr

	/* x_type values, 0 is reserved */
#define X_FILE		1		/* input is a file */
#define X_BUF		2		/* input is a buffer */

struct context cx;			/* the current context */