Issue #7462: Implement the stringlib fast search algorithm for the `rfind`,
`rindex`, `rsplit` and `rpartition` methods. Patch by Florent Xicluna.
diff --git a/Objects/stringobject.c b/Objects/stringobject.c
index 02aabf2..0f3874e 100644
--- a/Objects/stringobject.c
+++ b/Objects/stringobject.c
@@ -1576,13 +1576,10 @@
static PyObject *
string_split(PyStringObject *self, PyObject *args)
{
- Py_ssize_t len = PyString_GET_SIZE(self), n, i, j;
+ Py_ssize_t len = PyString_GET_SIZE(self), n, i, j, pos;
Py_ssize_t maxsplit = -1, count=0;
const char *s = PyString_AS_STRING(self), *sub;
PyObject *list, *str, *subobj = Py_None;
-#ifdef USE_FAST
- Py_ssize_t pos;
-#endif
if (!PyArg_ParseTuple(args, "|On:split", &subobj, &maxsplit))
return NULL;
@@ -1612,28 +1609,15 @@
if (list == NULL)
return NULL;
-#ifdef USE_FAST
i = j = 0;
while (maxsplit-- > 0) {
pos = fastsearch(s+i, len-i, sub, n, FAST_SEARCH);
if (pos < 0)
break;
- j = i+pos;
+ j = i + pos;
SPLIT_ADD(s, i, j);
i = j + n;
}
-#else
- i = j = 0;
- while ((j+n <= len) && (maxsplit-- > 0)) {
- for (; j+n <= len; j++) {
- if (Py_STRING_MATCH(s, j, sub, n)) {
- SPLIT_ADD(s, i, j);
- i = j = j + n;
- break;
- }
- }
- }
-#endif
SPLIT_ADD(s, i, len);
FIX_PREALLOC_SIZE(list);
return list;
@@ -1801,9 +1785,9 @@
static PyObject *
string_rsplit(PyStringObject *self, PyObject *args)
{
- Py_ssize_t len = PyString_GET_SIZE(self), n, i, j;
+ Py_ssize_t len = PyString_GET_SIZE(self), n, j, pos;
Py_ssize_t maxsplit = -1, count=0;
- const char *s, *sub;
+ const char *s = PyString_AS_STRING(self), *sub;
PyObject *list, *str, *subobj = Py_None;
if (!PyArg_ParseTuple(args, "|On:rsplit", &subobj, &maxsplit))
@@ -1835,18 +1819,13 @@
return NULL;
j = len;
- i = j - n;
- s = PyString_AS_STRING(self);
- while ( (i >= 0) && (maxsplit-- > 0) ) {
- for (; i>=0; i--) {
- if (Py_STRING_MATCH(s, i, sub, n)) {
- SPLIT_ADD(s, i + n, j);
- j = i;
- i -= n;
- break;
- }
- }
+ while (maxsplit-- > 0) {
+ pos = fastsearch(s, j, sub, n, FAST_RSEARCH);
+ if (pos < 0)
+ break;
+ SPLIT_ADD(s, pos + n, j);
+ j = pos;
}
SPLIT_ADD(s, 0, j);
FIX_PREALLOC_SIZE(list);