[Python-checkins] python/dist/src/Objects unicodeobject.c, 2.219,
2.220
tim_one at users.sourceforge.net
tim_one at users.sourceforge.net
Fri Aug 27 03:49:35 CEST 2004
Update of /cvsroot/python/python/dist/src/Objects
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv15103/Objects
Modified Files:
unicodeobject.c
Log Message:
PyUnicode_Join(): Two primary aims:
1. u1.join([u2]) is u2
2. Be more careful about C-level int overflow.
Since PySequence_Fast() isn't needed to achieve #1, it's not used -- but
the code could sure be simpler if it were.
Index: unicodeobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/unicodeobject.c,v
retrieving revision 2.219
retrieving revision 2.220
diff -u -d -r2.219 -r2.220
--- unicodeobject.c 4 Aug 2004 07:38:35 -0000 2.219
+++ unicodeobject.c 27 Aug 2004 01:49:32 -0000 2.220
@@ -3975,49 +3975,110 @@
return 1;
}
-PyObject *PyUnicode_Join(PyObject *separator,
- PyObject *seq)
+PyObject *
+PyUnicode_Join(PyObject *separator, PyObject *seq)
{
+ PyObject *internal_separator = NULL;
Py_UNICODE *sep;
- int seplen;
+ size_t seplen;
PyUnicodeObject *res = NULL;
- int reslen = 0;
- Py_UNICODE *p;
- int sz = 100;
+ size_t sz; /* # allocated bytes for string in res */
+ size_t reslen; /* # used bytes */
+ Py_UNICODE *p; /* pointer to free byte in res's string area */
+ PyObject *it; /* iterator */
+ PyObject *item;
int i;
- PyObject *it;
+ PyObject *temp;
it = PyObject_GetIter(seq);
if (it == NULL)
return NULL;
+ item = PyIter_Next(it);
+ if (item == NULL) {
+ if (PyErr_Occurred())
+ goto onError;
+ /* empty sequence; return u"" */
+ res = _PyUnicode_New(0);
+ goto Done;
+ }
+
+ /* If this is the only item, maybe we can get out cheap. */
+ res = (PyUnicodeObject *)item;
+ item = PyIter_Next(it);
+ if (item == NULL) {
+ if (PyErr_Occurred())
+ goto onError;
+ /* There's only one item in the sequence. */
+ if (PyUnicode_CheckExact(res)) /* whatever.join([u]) -> u */
+ goto Done;
+ }
+
+ /* There are at least two to join (item != NULL), or there's only
+ * one but it's not an exact Unicode (item == NULL). res needs
+ * conversion to Unicode in either case.
+ * Caution: we may need to ensure a copy is made, and that's trickier
+ * than it sounds because, e.g., PyUnicode_FromObject() may return
+ * a shared object (which must not be mutated).
+ */
+ if (! PyUnicode_Check(res) && ! PyString_Check(res)) {
+ PyErr_Format(PyExc_TypeError,
+ "sequence item 0: expected string or Unicode,"
+ " %.80s found",
+ res->ob_type->tp_name);
+ Py_XDECREF(item);
+ goto onError;
+ }
+ temp = PyUnicode_FromObject((PyObject *)res);
+ if (temp == NULL) {
+ Py_XDECREF(item);
+ goto onError;
+ }
+ Py_DECREF(res);
+ if (item == NULL) {
+ /* res was the only item */
+ res = (PyUnicodeObject *)temp;
+ goto Done;
+ }
+ /* There are at least two items. As above, temp may be a shared object,
+ * so we need to copy it.
+ */
+ reslen = PyUnicode_GET_SIZE(temp);
+ sz = reslen + 100; /* breathing room */
+ if (sz < reslen || sz > INT_MAX) /* overflow -- no breathing room */
+ sz = reslen;
+ res = _PyUnicode_New(sz);
+ if (res == NULL) {
+ Py_DECREF(item);
+ goto onError;
+ }
+ p = PyUnicode_AS_UNICODE(res);
+ Py_UNICODE_COPY(p, PyUnicode_AS_UNICODE(temp), (int)reslen);
+ p += reslen;
+ Py_DECREF(temp);
+
if (separator == NULL) {
Py_UNICODE blank = ' ';
sep = ␣
seplen = 1;
}
else {
- separator = PyUnicode_FromObject(separator);
- if (separator == NULL)
+ internal_separator = PyUnicode_FromObject(separator);
+ if (internal_separator == NULL) {
+ Py_DECREF(item);
goto onError;
- sep = PyUnicode_AS_UNICODE(separator);
- seplen = PyUnicode_GET_SIZE(separator);
+ }
+ sep = PyUnicode_AS_UNICODE(internal_separator);
+ seplen = PyUnicode_GET_SIZE(internal_separator);
}
- res = _PyUnicode_New(sz);
- if (res == NULL)
- goto onError;
- p = PyUnicode_AS_UNICODE(res);
- reslen = 0;
+ i = 1;
+ do {
+ size_t itemlen;
+ size_t newreslen;
- for (i = 0; ; ++i) {
- int itemlen;
- PyObject *item = PyIter_Next(it);
- if (item == NULL) {
- if (PyErr_Occurred())
- goto onError;
- break;
- }
+ /* Catenate the separator, then item. */
+ /* First convert item to Unicode. */
if (!PyUnicode_Check(item)) {
PyObject *v;
if (!PyString_Check(item)) {
@@ -4034,36 +4095,55 @@
if (item == NULL)
goto onError;
}
+ /* Make sure we have enough space for the separator and the item. */
itemlen = PyUnicode_GET_SIZE(item);
- while (reslen + itemlen + seplen >= sz) {
- if (_PyUnicode_Resize(&res, sz*2) < 0) {
+ newreslen = reslen + seplen + itemlen;
+ if (newreslen < reslen || newreslen > INT_MAX)
+ goto Overflow;
+ if (newreslen > sz) {
+ do {
+ size_t oldsize = sz;
+ sz += sz;
+ if (sz < oldsize || sz > INT_MAX)
+ goto Overflow;
+ } while (newreslen > sz);
+ if (_PyUnicode_Resize(&res, (int)sz) < 0) {
Py_DECREF(item);
goto onError;
}
- sz *= 2;
- p = PyUnicode_AS_UNICODE(res) + reslen;
- }
- if (i > 0) {
- Py_UNICODE_COPY(p, sep, seplen);
- p += seplen;
- reslen += seplen;
+ p = PyUnicode_AS_UNICODE(res) + reslen;
}
- Py_UNICODE_COPY(p, PyUnicode_AS_UNICODE(item), itemlen);
+ Py_UNICODE_COPY(p, sep, (int)seplen);
+ p += seplen;
+ Py_UNICODE_COPY(p, PyUnicode_AS_UNICODE(item), (int)itemlen);
p += itemlen;
- reslen += itemlen;
Py_DECREF(item);
- }
- if (_PyUnicode_Resize(&res, reslen) < 0)
+ reslen = newreslen;
+
+ ++i;
+ item = PyIter_Next(it);
+ } while (item != NULL);
+ if (PyErr_Occurred())
goto onError;
- Py_XDECREF(separator);
+ if (_PyUnicode_Resize(&res, (int)reslen) < 0)
+ goto onError;
+
+ Done:
+ Py_XDECREF(internal_separator);
Py_DECREF(it);
return (PyObject *)res;
+ Overflow:
+ PyErr_SetString(PyExc_OverflowError,
+ "join() is too long for a Python string");
+ Py_DECREF(item);
+ /* fall through */
+
onError:
- Py_XDECREF(separator);
- Py_XDECREF(res);
+ Py_XDECREF(internal_separator);
Py_DECREF(it);
+ Py_XDECREF(res);
return NULL;
}
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