[Patches] fix string methods implementing slice-like arguments (was:issues with int/long on 64bit platforms - eg stringobject (PR#306))

[Trent Mick]

Decription:

Fix the string methods that implement slice-like semantics with
optional args (count, find, endswith, etc.) to properly handle
indeces outside [INT_MIN, INT_MAX]. Previously the "i" formatter
for PyArg_ParseTuple was used to get the indeces. These could overflow.

This patch changes the string methods to use the "O&" formatter with
the slice_index() function from ceval.c which is used to do the same
job for Python code slices (e.g. 'abcabcabc'[0:1000000000L]). slice_index()
is renamed _PyEval_SliceIndex() and is now exported. As well, the return
values for success/fail were changed to make slice_index directly
usable as required by the "O&" formatter.


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Patch:


--- main/Apps/Perlium/Python/dist/src/Include/ceval.h.~1~	Wed May  3 15:45:50 2000
+++ main/Apps/Perlium/Python/dist/src/Include/ceval.h	Wed May  3 15:45:50 2000
@@ -144,6 +144,9 @@
 
 #endif /* !WITH_THREAD */
 
+extern DL_IMPORT(int) _PyEval_SliceIndex Py_PROTO((PyObject *, int *));
+
+
 #ifdef __cplusplus
 }
 #endif
--- main/Apps/Perlium/Python/dist/src/Objects/stringobject.c.~1~	Wed May  3 15:45:50 2000
+++ main/Apps/Perlium/Python/dist/src/Objects/stringobject.c	Wed May  3 15:45:50 2000
@@ -825,8 +825,8 @@
 	int n, i = 0, last = INT_MAX;
 	PyObject *subobj;
 
-	if (!PyArg_ParseTuple(args, "O|ii:find/rfind/index/rindex", 
-			      &subobj, &i, &last))
+	if (!PyArg_ParseTuple(args, "O|O&O&:find/rfind/index/rindex", 
+		&subobj, _PyEval_SliceIndex, &i, _PyEval_SliceIndex, &last))
 		return -2;
 	if (PyString_Check(subobj)) {
 		sub = PyString_AS_STRING(subobj);
@@ -1197,8 +1197,10 @@
 	int m, r;
 	PyObject *subobj;
 
-	if (!PyArg_ParseTuple(args, "O|ii:count", &subobj, &i, &last))
+	if (!PyArg_ParseTuple(args, "O|O&O&:count", &subobj,
+		_PyEval_SliceIndex, &i, _PyEval_SliceIndex, &last))
 		return NULL;
+
 	if (PyString_Check(subobj)) {
 		sub = PyString_AS_STRING(subobj);
 		n = PyString_GET_SIZE(subobj);
@@ -1620,7 +1622,8 @@
 	int end = -1;
 	PyObject *subobj;
 
-	if (!PyArg_ParseTuple(args, "O|ii:startswith", &subobj, &start, &end))
+	if (!PyArg_ParseTuple(args, "O|O&O&:startswith", &subobj,
+		_PyEval_SliceIndex, &start, _PyEval_SliceIndex, &end))
 		return NULL;
 	if (PyString_Check(subobj)) {
 		prefix = PyString_AS_STRING(subobj);
@@ -1674,7 +1677,8 @@
 	int lower, upper;
 	PyObject *subobj;
 
-	if (!PyArg_ParseTuple(args, "O|ii:endswith", &subobj, &start, &end))
+	if (!PyArg_ParseTuple(args, "O|O&O&:endswith", &subobj,
+		_PyEval_SliceIndex, &start, _PyEval_SliceIndex, &end))
 		return NULL;
 	if (PyString_Check(subobj)) {
 		suffix = PyString_AS_STRING(subobj);
--- main/Apps/Perlium/Python/dist/src/Python/ceval.c.~1~	Wed May  3 15:45:50 2000
+++ main/Apps/Perlium/Python/dist/src/Python/ceval.c	Wed May  3 15:45:50 2000
@@ -80,7 +80,6 @@
 static PyObject *call_builtin Py_PROTO((PyObject *, PyObject *, PyObject *));
 static PyObject *call_function Py_PROTO((PyObject *, PyObject *, PyObject *));
 static PyObject *loop_subscript Py_PROTO((PyObject *, PyObject *));
-static int slice_index Py_PROTO((PyObject *, int *));
 static PyObject *apply_slice Py_PROTO((PyObject *, PyObject *, PyObject *));
 static int assign_slice Py_PROTO((PyObject *, PyObject *,
 				  PyObject *, PyObject *));
@@ -2585,8 +2584,12 @@
 	return NULL;
 }
 
-static int
-slice_index(v, pi)
+/* Extract a slice index from a PyInt or PyLong, the index is bound to
+   the range [-INT_MAX+1, INTMAX]. Returns 0 and an exception if there is
+   and error. Returns 1 on success.*/
+
+int
+_PyEval_SliceIndex(v, pi)
 	PyObject *v;
 	int *pi;
 {
@@ -2602,7 +2605,7 @@
 				if (!PyErr_ExceptionMatches( PyExc_OverflowError ) ) {
 					/* It's not an overflow error, so just 
 					   signal an error */
-					return -1;
+					return 0;
 				}
 
 				/* It's an overflow error, so we need to 
@@ -2612,7 +2615,7 @@
 
 				/* Create a long integer with a value of 0 */
 				long_zero = PyLong_FromLong( 0L );
-				if (long_zero == NULL) return -1;
+				if (long_zero == NULL) return 0;
 
 				/* Check sign */
 				if (PyObject_Compare(long_zero, v) < 0)
@@ -2628,7 +2631,7 @@
 		} else {
 			PyErr_SetString(PyExc_TypeError,
 					"slice index must be int");
-			return -1;
+			return 0;
 		}
 		/* Truncate -- very long indices are truncated anyway */
 		if (x > INT_MAX)
@@ -2637,7 +2640,7 @@
 			x = 0;
 		*pi = x;
 	}
-	return 0;
+	return 1;
 }
 
 static PyObject *
@@ -2645,9 +2648,9 @@
 	PyObject *u, *v, *w;
 {
 	int ilow = 0, ihigh = INT_MAX;
-	if (slice_index(v, &ilow) != 0)
+	if (!_PyEval_SliceIndex(v, &ilow))
 		return NULL;
-	if (slice_index(w, &ihigh) != 0)
+	if (!_PyEval_SliceIndex(w, &ihigh))
 		return NULL;
 	return PySequence_GetSlice(u, ilow, ihigh);
 }
@@ -2657,9 +2660,9 @@
 	PyObject *u, *v, *w, *x;
 {
 	int ilow = 0, ihigh = INT_MAX;
-	if (slice_index(v, &ilow) != 0)
+	if (!_PyEval_SliceIndex(v, &ilow))
 		return -1;
-	if (slice_index(w, &ihigh) != 0)
+	if (!_PyEval_SliceIndex(w, &ihigh))
 		return -1;
 	if (x == NULL)
 		return PySequence_DelSlice(u, ilow, ihigh);
End of Patch.