Fix off-by-one error in long_repr.
Implement long_pow.
diff --git a/Objects/longobject.c b/Objects/longobject.c
index a2fccc5..badc3df 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -278,6 +278,7 @@
assert(p > q);
do {
} while ((*q++ = *p++) != '\0');
+ q--;
resizestring((object **)&str, (int) (q - GETSTRINGVALUE(str)));
}
return str;
@@ -844,16 +845,60 @@
}
static object *
-long_pow(v, w)
- longobject *v;
- register object *w;
+long_pow(a, w)
+ longobject *a;
+ object *w;
{
+ register longobject *b;
+ longobject *z;
+ int size_b, i;
+
if (!is_longobject(w)) {
err_badarg();
return NULL;
}
- err_setstr(SystemError, "long power not implemented");
- return NULL;
+
+ b = (longobject *)w;
+ size_b = b->ob_size;
+ if (size_b < 0) {
+ err_setstr(RuntimeError, "long integer to the negative power");
+ return NULL;
+ }
+
+ z = (longobject *)newlongobject(1L);
+
+ INCREF(a);
+ for (i = 0; i < size_b; ++i) {
+ digit bi = b->ob_digit[i];
+ int j;
+
+ for (j = 0; j < SHIFT; ++j) {
+ longobject *temp;
+
+ if (bi & 1) {
+ temp = (longobject *)long_mul(z, (object *)a);
+ DECREF(z);
+ z = temp;
+ if (z == NULL)
+ break;
+ }
+ bi >>= 1;
+ if (bi == 0 && i+1 == size_b)
+ break;
+ temp = (longobject *)long_mul(a, (object *)a);
+ DECREF(a);
+ a = temp;
+ if (a == NULL) {
+ DECREF(z);
+ z = NULL;
+ break;
+ }
+ }
+ if (a == NULL)
+ break;
+ }
+ XDECREF(a);
+ return (object *)z;
}
static object *