usr/src/cmd/ex/ex_re.h

/* Copyright (c) 1980 Regents of the University of California */
/* sccs id:     @(#)ex_re.h     6.1 10/18/80  */
/*
 * 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 CEOFC   17
#define CKET    18
#define CCHR    20
#define CBRC    24
#define CLET    25