Patch #976880: add mmap .rfind() method, and 'end' paramter to .find().
Contributed by John Lenton.
diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index 9a39b24..dd35c10 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -248,19 +248,22 @@
}
static PyObject *
-mmap_find_method(mmap_object *self,
- PyObject *args)
+mmap_gfind(mmap_object *self,
+ PyObject *args,
+ int reverse)
{
Py_ssize_t start = self->pos;
+ Py_ssize_t end = self->size;
char *needle;
Py_ssize_t len;
CHECK_VALID(NULL);
- if (!PyArg_ParseTuple(args, "s#|n:find", &needle, &len, &start)) {
+ if (!PyArg_ParseTuple(args, reverse ? "s#|nn:rfind" : "s#|nn:find",
+ &needle, &len, &start, &end)) {
return NULL;
} else {
char *p;
- char *e = self->data + self->size;
+ char sign = reverse ? -1 : 1;
if (start < 0)
start += self->size;
@@ -269,7 +272,18 @@
else if ((size_t)start > self->size)
start = self->size;
- for (p = self->data + start; p + len <= e; ++p) {
+ if (end < 0)
+ end += self->size;
+ if (end < 0)
+ end = 0;
+ else if ((size_t)end > self->size)
+ end = self->size;
+
+ start += (Py_ssize_t)self->data;
+ end += (Py_ssize_t)self->data;
+
+ for (p = (char *)(reverse ? end - len : start);
+ p >= (char *)start && p + len <= (char *)end; p+=sign) {
Py_ssize_t i;
for (i = 0; i < len && needle[i] == p[i]; ++i)
/* nothing */;
@@ -281,6 +295,20 @@
}
}
+static PyObject *
+mmap_find_method(mmap_object *self,
+ PyObject *args)
+{
+ return mmap_gfind(self, args, 0);
+}
+
+static PyObject *
+mmap_rfind_method(mmap_object *self,
+ PyObject *args)
+{
+ return mmap_gfind(self, args, 1);
+}
+
static int
is_writeable(mmap_object *self)
{
@@ -593,6 +621,7 @@
static struct PyMethodDef mmap_object_methods[] = {
{"close", (PyCFunction) mmap_close_method, METH_NOARGS},
{"find", (PyCFunction) mmap_find_method, METH_VARARGS},
+ {"rfind", (PyCFunction) mmap_rfind_method, METH_VARARGS},
{"flush", (PyCFunction) mmap_flush_method, METH_VARARGS},
{"move", (PyCFunction) mmap_move_method, METH_VARARGS},
{"read", (PyCFunction) mmap_read_method, METH_VARARGS},