[PATCH 2/4] strbuf_split_buf(): simplify iteration

From: Michael Haggerty <mhagger@alum.mit.edu>
Date: Nov 4, 2012, 06:46 UTC
Message-ID: <1352011614-29334-3-git-send-email-mhagger@alum.mit.edu>
In-Reply-To: <1352011614-29334-1-git-send-email-mhagger@alum.mit.edu>

While iterating, update str and slen to keep track of the part of the string that hasn't been processed yet rather than computing things relative to the start of the original string. This eliminates one local variable, reduces the scope of another, and reduces the amount of arithmetic needed within the loop.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 strbuf.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/strbuf.c b/strbuf.c
index 5256c2a..c7cd529 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -110,25 +110,22 @@ struct strbuf **strbuf_split_buf(const char *str, size_t slen, int delim, int ma
 {
 	struct strbuf **ret = NULL;
 	size_t nr = 0, alloc = 0;
-	const char *n, *p;
 	struct strbuf *t;
 
-	p = n = str;
-	while (n < str + slen) {
-		int len;
-		if (max <= 0 || nr + 1 < max)
-			n = memchr(n, delim, slen - (n - str));
-		else
-			n = NULL;
-		if (!n)
-			n = str + slen - 1;
-		len = n - p + 1;
+	while (slen) {
+		int len = slen;
+		if (max <= 0 || nr + 1 < max) {
+			const char *end = memchr(str, delim, slen);
+			if (end)
+				len = end - str + 1;
+		}
 		t = xmalloc(sizeof(struct strbuf));
 		strbuf_init(t, len);
-		strbuf_add(t, p, len);
+		strbuf_add(t, str, len);
 		ALLOC_GROW(ret, nr + 2, alloc);
 		ret[nr++] = t;
-		p = ++n;
+		str += len;
+		slen -= len;
 	}
 	ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
 	ret[nr] = NULL;

-- 
1.8.0