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-rw-r--r--string.c40
1 files changed, 3 insertions, 37 deletions
diff --git a/string.c b/string.c
index c864f1f..9044902 100644
--- a/string.c
+++ b/string.c
@@ -838,48 +838,14 @@ rb_str_index(str, sub, offset)
VALUE str, sub;
long offset;
{
- char *s, *e, *p;
- long len;
- int d, hx, hy, i;
-
if (offset < 0) {
offset += RSTRING(str)->len;
if (offset < 0) return -1;
}
if (RSTRING(str)->len - offset < RSTRING(sub)->len) return -1;
- s = RSTRING(str)->ptr+offset;
- p = RSTRING(sub)->ptr;
- len = RSTRING(sub)->len;
- if (len == 0) return offset;
- e = RSTRING(str)->ptr + RSTRING(str)->len - len + 1;
-
- /* seach using Karp-Rabin algolithm described in:
-
- EXACT STRING MATCHING ALGORITHMS
- http://www-igm.univ-mlv.fr/~lecroq/string/index.html
- */
-
-#define KR_REHASH(a, b, h) ((((h) - (a)*d) << 1) + (b))
-
- /* Preprocessing */
- /* computes d = 2^(m-1) with
- the left-shift operator */
- for (d = i = 1; i < len; ++i)
- d = (d<<1);
-
- for (hy = hx = i = 0; i < len; ++i) {
- hx = ((hx<<1) + p[i]);
- hy = ((hy<<1) + s[i]);
- }
-
- /* Searching */
- while (s < e) {
- if (hx == hy && rb_memcmp(p, s, len) == 0)
- return (s-(RSTRING(str)->ptr));
- hy = KR_REHASH(*s, *(s+len), hy);
- s++;
- }
- return -1;
+ if (RSTRING(sub)->len == 0) return offset;
+ return rb_memsearch(RSTRING(sub)->ptr, RSTRING(sub)->len,
+ RSTRING(str)->ptr+offset, RSTRING(str)->len-offset);
}
static VALUE