Added more comments to the new structseq repr code and implemented several of Neal's suggestions.
diff --git a/Objects/structseq.c b/Objects/structseq.c
index 8e27441..b6126ba 100644
--- a/Objects/structseq.c
+++ b/Objects/structseq.c
@@ -230,23 +230,37 @@
static PyObject *
structseq_repr(PyStructSequence *obj)
{
- PyObject *tup, *val, *repr;
- PyTypeObject *typ = Py_TYPE(obj);
- int i, len;
- char buf[250+5]; /* "...)\0" */
- char *cname, *crepr;
- char *pbuf = buf;
- char *endbuf = &buf[250];
+ /* buffer and type size were chosen well considered. */
+#define REPR_BUFFER_SIZE 512
+#define TYPE_MAXSIZE 100
- strncpy(pbuf, typ->tp_name, 50);
- pbuf += strlen(typ->tp_name) > 50 ? 50 : strlen(typ->tp_name);
- *pbuf++ = '(';
+ PyObject *tup;
+ PyTypeObject *typ = Py_TYPE(obj);
+ int i, removelast = 0;
+ Py_ssize_t len;
+ char buf[REPR_BUFFER_SIZE];
+ char *endofbuf, *pbuf = buf;
+
+ /* pointer to end of writeable buffer; safes space for "...)\0" */
+ endofbuf= &buf[REPR_BUFFER_SIZE-5];
if ((tup = make_tuple(obj)) == NULL) {
return NULL;
}
+
+ /* "typename(", limited to TYPE_MAXSIZE */
+ len = strlen(typ->tp_name) > TYPE_MAXSIZE ? TYPE_MAXSIZE :
+ strlen(typ->tp_name);
+ strncpy(pbuf, typ->tp_name, len);
+ pbuf += len;
+ *pbuf++ = '(';
+
for (i=0; i < VISIBLE_SIZE(obj); i++) {
+ PyObject *val, *repr;
+ char *cname, *crepr;
+
cname = typ->tp_members[i].name;
+
val = PyTuple_GetItem(tup, i);
if (cname == NULL || val == NULL) {
return NULL;
@@ -262,8 +276,10 @@
Py_DECREF(repr);
return NULL;
}
- len = strlen(cname) + strlen(crepr) + 3;
- if ((pbuf+len) < endbuf) {
+
+ /* + 3: keep space for "=" and ", " */
+ len = strlen(cname) + strlen(crepr) + 3;
+ if ((pbuf+len) <= endofbuf) {
strcpy(pbuf, cname);
pbuf += strlen(cname);
*pbuf++ = '=';
@@ -271,23 +287,26 @@
pbuf += strlen(crepr);
*pbuf++ = ',';
*pbuf++ = ' ';
+ removelast = 1;
Py_DECREF(repr);
}
else {
strcpy(pbuf, "...");
- pbuf += 5;
+ pbuf += 3;
+ removelast = 0;
Py_DECREF(repr);
break;
}
}
Py_DECREF(tup);
-
- pbuf-=2;
+ if (removelast) {
+ /* overwrite last ", " */
+ pbuf-=2;
+ }
*pbuf++ = ')';
*pbuf = '\0';
- repr = PyString_FromString(buf);
- return repr;
+ return PyString_FromString(buf);
}
static PyObject *