d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

libregex: implement \b and \B (word boundary, not word boundary)

Browse Source 
This is the last of the needed GNU expressions before we can unleash bsdgrep
by default. \b is effectively an agnostic equivalent of \< and \>, while
\B will match every space that isn't making a transition from
nonchar -> char or char -> nonchar.
This commit is contained in:
Kyle Evans 2020-12-05 03:16:05 +00:00
parent ca53e5aedf
commit 6b986646d4
5 changed files with 61 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
contrib/netbsd-tests/lib/libc/regex/data/meta.in
View File

@ -5,7 +5,7 @@ a\*c & a*c a*c
a\\b & a\b a\b
a\\\*b & a\*b a\*b
# Begin FreeBSD
a\bc &C EESCAPE
a\bc & abc
# End FreeBSD
a\ &C EESCAPE
a\\bc & a\bc a\bc

37
lib/libc/regex/engine.c
View File

@ -118,6 +118,7 @@ static states step(struct re_guts *g, sopno start, sopno stop, states bef, wint_
#define BOW (BOL-4)
#define EOW (BOL-5)
#define BADCHAR (BOL-6)
#define NWBND (BOL-7)
#define NONCHAR(c) ((c) <= OUT)
/* sflags */
#define SBOS 0x0001
@ -463,6 +464,8 @@ dissect(struct match *m,
case OEOW:
case OBOS:
case OEOS:
case OWBND:
case ONWBND:
break;
case OANY:
case OANYOF:
@ -691,6 +694,21 @@ backref(struct match *m,
else
return(NULL);
break;
case OWBND:
if (ISBOW(m, sp) || ISEOW(m, sp))
{ /* yes */ }
else
return(NULL);
break;
case ONWBND:
if (((sp == m->beginp) && !ISWORD(*sp)) ||
(sp == m->endp && !ISWORD(*(sp - 1))))
{ /* yes, beginning/end of subject */ }
else if (ISWORD(*(sp - 1)) == ISWORD(*sp))
{ /* yes, beginning/end of subject */ }
else
return(NULL);
break;
case OBOW:
if (ISBOW(m, sp))
{ /* yes */ }
@ -916,6 +934,17 @@ walk(struct match *m, const char *start, const char *stop, sopno startst,
st = step(m->g, startst, stopst, st, flagch, st, sflags);
SP("sboweow", st, c);
}
if (lastc != OUT && c != OUT &&
ISWORD(lastc) == ISWORD(c)) {
flagch = NWBND;
} else if ((lastc == OUT && !ISWORD(c)) ||
(c == OUT && !ISWORD(lastc))) {
flagch = NWBND;
}
if (flagch == NWBND) {
st = step(m->g, startst, stopst, st, flagch, st, sflags);
SP("snwbnd", st, c);
}
/* are we done? */
if (ISSET(st, stopst)) {
@ -1017,6 +1046,14 @@ step(struct re_guts *g,
if (ch == EOW)
FWD(aft, bef, 1);
break;
case OWBND:
if (ch == BOW || ch == EOW)
FWD(aft, bef, 1);
break;
case ONWBND:
if (ch == NWBND)
FWD(aft, aft, 1);
break;
case OANY:
if (!NONCHAR(ch))
FWD(aft, bef, 1);

16
lib/libc/regex/regcomp.c
View File

@ -486,6 +486,12 @@ p_ere_exp(struct parse *p, struct branchc *bc)
case '\'':
EMIT(OEOS, 0);
break;
case 'B':
EMIT(ONWBND, 0);
break;
case 'b':
EMIT(OWBND, 0);
break;
case 'W':
case 'w':
case 'S':
@ -845,6 +851,12 @@ p_simp_re(struct parse *p, struct branchc *bc)
case BACKSL|'\'':
EMIT(OEOS, 0);
break;
case BACKSL|'B':
EMIT(ONWBND, 0);
break;
case BACKSL|'b':
EMIT(OWBND, 0);
break;
case BACKSL|'W':
case BACKSL|'w':
case BACKSL|'S':
@ -1892,6 +1904,8 @@ findmust(struct parse *p, struct re_guts *g)
case OEOL:
case OBOS:
case OEOS:
case OWBND:
case ONWBND:
case O_QUEST:
case O_CH:
case OEND:
@ -2043,6 +2057,8 @@ altoffset(sop *scan, int offset)
try++;
case OBOW:
case OEOW:
case OWBND:
case ONWBND:
case OLPAREN:
case ORPAREN:
case OOR2:

2
lib/libc/regex/regex2.h
View File

@ -106,6 +106,8 @@ typedef unsigned long sopno;
#define OEOW (20L<<OPSHIFT) /* end word - */
#define OBOS (21L<<OPSHIFT) /* begin subj. - */
#define OEOS (22L<<OPSHIFT) /* end subj. - */
#define OWBND (23L<<OPSHIFT) /* word bound - */
#define ONWBND (24L<<OPSHIFT) /* not bound - */
/*
* Structures for [] character-set representation.

12
lib/libregex/tests/gnuext.in
View File

@ -17,14 +17,12 @@ a\|b\|c b abc a
\s\+ b aSNTb SNT
# Word boundaries (\b, \B, \<, \>, \`, \')
# (is/not boundary, start/end word, start/end subject string)
# Most of these are disabled for the moment, and will be re-enabled as
# we become feature complete.
#\babc\b & <abc> abc
\babc\b & <abc> abc
\<abc\> & <abc> abc
#\Babc\B & abc
#\B[abc]\B & <abc> b
#\B[abc]+ - <abc> bc
#\B[abc]\+ b <abc> bc
\Babc\B & abc
\B[abc]\B & <abc> b
\B[abc]+ - <abc> bc
\B[abc]\+ b <abc> bc
\`abc & abc abc
abc\' & abc abc
\`abc\' & abc abc