2BSD/src/ex/ex_re.h

/* Copyright (c) 1979 Regents of the University of California */
/*
 * Regular expression definitions.
 * The regular expressions in ex are similar to those in ed,
 * with the addition of the word boundaries from Toronto ed
 * and allowing character classes to have [a-b] as in the shell.
 * The numbers for the nodes below are spaced further apart then
 * necessary because I at one time partially put in + and | (one or
 * more and alternation.)
 */
struct	regexp {
	char	Expbuf[ESIZE + 2];
	bool	Circfl;
	short	Nbra;
};

/*
 * There are three regular expressions here, the previous (in re),
 * the previous substitute (in subre) and the previous scanning (in scanre).
 * It would be possible to get rid of "re" by making it a stack parameter
 * to the appropriate routines.
 */
struct	regexp re;		/* Last re */
struct	regexp scanre;		/* Last scanning re */
struct	regexp subre;		/* Last substitute re */

/*
 * Defining circfl and expbuf like this saves us from having to change
 * old code in the ex_re.c stuff.
 */
#define	expbuf	re.Expbuf
#define	circfl	re.Circfl
#define	nbra	re.Nbra

/*
 * Since the phototypesetter v7-epsilon
 * C compiler doesn't have structure assignment...
 */
#define	savere(a)	copy(&a, &re, sizeof (struct regexp));
#define	resre(a)	copy(&re, &a, sizeof (struct regexp));

/*
 * Definitions for substitute
 */
char	*braslist[NBRA];	/* Starts of \(\)'ed text in lhs */
char	*braelist[NBRA];	/* Ends... */
char	rhsbuf[RHSSIZE];	/* Rhs of last substitute */

/*
 * Definitions of codes for the compiled re's.
 * The re algorithm is described in a paper
 * by K. Thompson in the CACM about 10 years ago
 * and is the same as in ed.
 */
#define	STAR	1

#define	CBRA	1
#define	CDOT	4
#define	CCL	8
#define	NCCL	12
#define	CDOL	16
#define	CEOF	17
#define	CKET	18
#define	CCHR	20
#define	CBRC	24
#define	CLET	25