Issue #4228: Pack negative values the same way as 2.4
in struct's L format.
diff --git a/Lib/test/test_struct.py b/Lib/test/test_struct.py
index 7ecb6ac..f135150 100644
--- a/Lib/test/test_struct.py
+++ b/Lib/test/test_struct.py
@@ -3,6 +3,8 @@
import struct
import array
import warnings
+warnings.filterwarnings("ignore", "struct integer overflow masking is deprecated",
+ DeprecationWarning)
import sys
ISBIGENDIAN = sys.byteorder == "big"
@@ -535,6 +537,17 @@
test_1530559()
+## Issue 4228. Packing a negative unsigned long warns,
+# but then still should give a value with the
+# topmost bit set.
+
+def test_issue4228():
+ # Packing a long may yield either 32 or 64 bits
+ x = struct.pack('L', -1)[:4]
+ vereq(x, '\xff'*4)
+
+test_issue4228()
+
###########################################################################
# Packing and unpacking to/from buffers.
diff --git a/Misc/NEWS b/Misc/NEWS
index 97efe21..a98ae2c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -217,6 +217,8 @@
Extension Modules
-----------------
+- Issue #4228: Pack negative values the same way as 2.4 in struct's L format.
+
- Security Issue #2: imageop did not validate arguments correctly and could
segfault as a result.
diff --git a/Modules/_struct.c b/Modules/_struct.c
index 41183fa..e2a883d 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -645,7 +645,7 @@
return -1;
#if (SIZEOF_LONG > SIZEOF_INT)
if ((x < ((long)INT_MIN)) || (x > ((long)INT_MAX)))
- return _range_error(f, 0);
+ RANGE_ERROR(x, f, 0, -1);
#endif
y = (int)x;
memcpy(p, (char *)&y, sizeof y);
@@ -657,12 +657,12 @@
{
unsigned long x;
unsigned int y;
- if (get_ulong(v, &x) < 0)
- return _range_error(f, 1);
+ if (get_wrapped_ulong(v, &x) < 0)
+ return -1;
y = (unsigned int)x;
#if (SIZEOF_LONG > SIZEOF_INT)
if (x > ((unsigned long)UINT_MAX))
- return _range_error(f, 1);
+ RANGE_ERROR(y, f, 1, -1);
#endif
memcpy(p, (char *)&y, sizeof y);
return 0;
@@ -682,8 +682,8 @@
np_ulong(char *p, PyObject *v, const formatdef *f)
{
unsigned long x;
- if (get_ulong(v, &x) < 0)
- return _range_error(f, 1);
+ if (get_wrapped_ulong(v, &x) < 0)
+ return -1;
memcpy(p, (char *)&x, sizeof x);
return 0;
}