Add a test, and fix the C implementation, for farmatting a 64-bit oid.

zopefoundation · Oct 20, 2018 · 8e75681 · 8e75681
1 parent 99c9462
commit 8e75681
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Showing 2 changed files with 33 additions and 10 deletions.
diff --git a/persistent/cPersistence.c b/persistent/cPersistence.c
@@ -16,6 +16,7 @@ static char cPersistence_doc_string[] =
   "\n"
   "$Id$\n";
 
+#include <stdint.h>
 #include "cPersistence.h"
 #include "structmember.h"
 
@@ -1430,7 +1431,8 @@ Per_repr(cPersistentObject *self)
     PyObject *result = NULL;
 
     unsigned char* oid_bytes;
-    unsigned long long oid_value;
+    char buf[20];
+    uint64_t oid_value;
 
     prepr = PyObject_GetAttrString((PyObject*)Py_TYPE(self), "_p_repr");
     if (prepr)
@@ -1453,15 +1455,21 @@ Per_repr(cPersistentObject *self)
 
     if (self->oid && PyBytes_Check(self->oid) && PyBytes_GET_SIZE(self->oid) == 8) {
         oid_bytes = (unsigned char*)PyBytes_AS_STRING(self->oid);
-        oid_value = ((unsigned long long)oid_bytes[0] << 56)
-            | ((unsigned long long)oid_bytes[1] << 48)
-            | ((unsigned long long)oid_bytes[2] << 40)
-            | ((unsigned long long)oid_bytes[3] << 32)
-            | ((unsigned long long)oid_bytes[4] << 24)
-            | ((unsigned long long)oid_bytes[5] << 16)
-            | ((unsigned long long)oid_bytes[6] << 8)
-            | ((unsigned long long)oid_bytes[7]);
-        oid_str = PyUnicode_FromFormat(" oid 0x%x", oid_value);
+        oid_value = ((uint64_t)oid_bytes[0] << 56)
+            | ((uint64_t)oid_bytes[1] << 48)
+            | ((uint64_t)oid_bytes[2] << 40)
+            | ((uint64_t)oid_bytes[3] << 32)
+            | ((uint64_t)oid_bytes[4] << 24)
+            | ((uint64_t)oid_bytes[5] << 16)
+            | ((uint64_t)oid_bytes[6] << 8)
+            | ((uint64_t)oid_bytes[7]);
+        /*
+          Python's PyUnicode_FromFormat doesn't understand the ll
+          length modifier for %x, so to format a 64-bit value we need to
+          use stdio.
+        */
+        snprintf(buf, sizeof(buf) - 1, "%llx", oid_value);
+        oid_str = PyUnicode_FromFormat(" oid 0x%s", buf);
     }
 
     if (!oid_str) {

diff --git a/persistent/tests/test_persistence.py b/persistent/tests/test_persistence.py
@@ -1740,6 +1740,21 @@ def test_repr_oid_no_jar(self):
             result,
             "<persistent.Persistent object at 0xdeadbeef oid " + self._HEX_OID + ">")
 
+    def test_64bit_oid(self):
+        import struct
+        p = self._makeOne()
+        oid_value = 2 << 62
+        self.assertEqual(oid_value.bit_length(), 64)
+        oid = struct.pack(">Q", oid_value)
+        self.assertEqual(oid, b'\x80\x00\x00\x00\x00\x00\x00\x00')
+
+        p._p_oid = oid
+        result = self._normalized_repr(p)
+        self.assertEqual(
+            result,
+            '<persistent.Persistent object at 0xdeadbeef oid 0x8000000000000000>'
+        )
+
     def test_repr_no_oid_repr_jar_raises_exception(self):
         p = self._makeOne()