From 21702781bcc5154defda0b722d0f1c51ac416816 Mon Sep 17 00:00:00 2001
From: Werner Almesberger <werner@almesberger.net>
Date: Tue, 22 May 2012 13:51:57 -0300
Subject: [PATCH] b2/: use re_nsub instead of maintaining our own equivalent

We still need to count parentheses in prepare_re for the current index
into "units", but the rest can ue re_nsub.
---
 b2/subst.c | 12 ++++++------
 b2/subst.h |  1 -
 2 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/b2/subst.c b/b2/subst.c
index 7168ded..04ed9be 100644
--- a/b2/subst.c
+++ b/b2/subst.c
@@ -59,12 +59,12 @@ static void unit_expr(char **res, int *res_len, char unit)
 }
 
 
-static char *prepare_re(const char *re, int *parens, char *units)
+static char *prepare_re(const char *re, char *units)
 {
 	char *res = NULL;
 	int res_len = 0;
+	int parens = 0;
 
-	*parens = 0;
 	memset(units, 0, 10);
 	append_char(&res, &res_len, '^');
 	while (*re) {
@@ -85,11 +85,11 @@ static char *prepare_re(const char *re, int *parens, char *units)
 			re++;
 			break;
 		case '(':
-			(*parens)++;
+			parens++;
 			if (re[1] == '#' && re[2]) {
 				if (!isalpha(re[2]) || re[3] != ')')
 					yyerrorf("invalid (#unit) syntax");
-				units[*parens-1] = re[2];
+				units[parens-1] = re[2];
 				unit_expr(&res, &res_len, re[2]);
 				re += 3;
 				break;
@@ -115,7 +115,7 @@ struct subst *subst_match(const char *src, const char *re)
 
 	sub = alloc_subst(st_match);
 	sub->u.match.src = src;
-	tmp = prepare_re(re, &sub->u.match.parens, sub->u.match.units);
+	tmp = prepare_re(re, sub->u.match.units);
 	err = regcomp(&sub->u.match.re, tmp, REG_EXTENDED);
 	free(tmp);
 	if (err) {
@@ -326,7 +326,7 @@ static void check_chunks(const struct chunk *c, const struct parent *parent,
 			if (!parent)
 				yyerrorf("$%c without match",
 				    c->u.sub ? c->u.sub+'0' : '$');
-			parens = parent->sub->u.match.parens;
+			parens = parent->sub->u.match.re.re_nsub;
 			if (c->u.sub > parens)
 				yyerrorf("$%d but only %d parenthes%s",
 				    c->u.sub, parens,
diff --git a/b2/subst.h b/b2/subst.h
index 62e8718..70b6a15 100644
--- a/b2/subst.h
+++ b/b2/subst.h
@@ -56,7 +56,6 @@ struct subst {
 			regex_t re;
 			struct subst *block;
 			char units[NMATCH-1];
-			int parens; /* number of parentheses */
 		} match;
 		struct {
 			const char *dst;