Limit validity of URIFilename

Fixes #501

apsw/__init__.pyi

@@ -2222,7 +2222,9 @@ class URIFilename:
     or the main database flag is set.
 
     You can safely pass it on to the :class:`VFSFile` constructor
-    which knows how to get the name back out."""
+    which knows how to get the name back out.  The URIFilename is
+    only valid for the duration of the xOpen call.  If you save
+    and use the object later you will get an exception."""
     def filename(self) -> str:
         """Returns the filename."""
         ...

apsw/tests.py

@@ -5374,8 +5374,7 @@ def sourceCheckFunction(self, filename, name, lines):
                     f"file { filename } function { name } calls PyGILState_Ensure but does not have MakeExistingException"
                 )
         # not further checked
-        if name.split("_")[0] in ("ZeroBlobBind", "APSWVFS", "APSWVFSFile", "APSWBuffer", "FunctionCBInfo",
-                                  "apswurifilename"):
+        if name.split("_")[0] in ("ZeroBlobBind", "APSWVFS", "APSWVFSFile", "APSWBuffer", "FunctionCBInfo"):
             return
 
         checks = {
@@ -5457,6 +5456,11 @@ def sourceCheckFunction(self, filename, name, lines):
             "apswfcntl": {
                 "req": {}
             },
+            "apswurifilename": {
+                "req": {
+                    "check": "CHECK_SCOPE"
+                }
+            }
         }
 
         prefix, base = name.split("_", 1)
@@ -10400,13 +10404,17 @@ def __init__(self):
 
             def xOpen(self, name, flags):
                 assert isinstance(name, apsw.URIFilename)
-                name_catch.append(name)
+                name_catch.append((name, str(name)))
                 raise apsw.SQLError()
+
         t = TVFS()
 
         with contextlib.suppress(apsw.SQLError):
             apsw.Connection("/tmp/uri_test", vfs="uritest")
 
+        self.assertEqual(len(name_catch), 1)
+        uriname, urinamestr=name_catch[0]
+
         objects = (self.db,
                    db2,
                    db3,
@@ -10416,7 +10424,7 @@ def xOpen(self, name, flags):
                    apsw.zeroblob(3),
                    blob,
                    blob2,
-                   name_catch[0],
+                   uriname,
                    apsw.VFS("aname", ""),
                    apsw.VFSFile("", self.db.db_filename("main"),
                        [apsw.SQLITE_OPEN_MAIN_DB | apsw.SQLITE_OPEN_CREATE | apsw.SQLITE_OPEN_READWRITE, 0]),
@@ -10425,6 +10433,27 @@ def xOpen(self, name, flags):
         )
         for o in objects:
             self.assertNotEqual(repr(o), str(o))
+            # issue 501
+            if isinstance(o, apsw.URIFilename):
+                self.assertNotEqual(repr(o), urinamestr)
+                self.assertNotEqual(str(o), urinamestr)
+
+        # more issue 501
+        with contextlib.suppress(ValueError):
+            uriname.filename()
+            1/0
+        with contextlib.suppress(ValueError):
+            uriname.parameters
+            1/0
+        with contextlib.suppress(ValueError):
+            uriname.uri_boolean("name", False)
+            1/0
+        with contextlib.suppress(ValueError):
+            uriname.uri_int("name", 0)
+            1/0
+        with contextlib.suppress(ValueError):
+            uriname.uri_parameter("name")
+            1/0
 
     # This test is run last by deliberate name choice.  If it did
     # uncover any bugs there isn't much that can be done to turn the

doc/changes.rst

@@ -25,6 +25,10 @@ Provide detail when C implemented objects are printed. For example
 
 Added :meth:`URIFilename.parameters` (:issue:`496`)
 
+:class:`URIFilename` are only valid for the duration of the
+:meth:`VFS.xOpen` call.  If you save and use the object later you will
+get an exception.  (:issue:`501`)
+
 3.44.0.0
 ========
 

src/apsw.docstrings

@@ -2865,7 +2865,9 @@
 "or the main database flag is set.\n" \
 "\n" \
 "You can safely pass it on to the :class:`VFSFile` constructor\n" \
-"which knows how to get the name back out.\n" 
+"which knows how to get the name back out.  The URIFilename is\n" \
+"only valid for the duration of the xOpen call.  If you save\n" \
+"and use the object later you will get an exception.\n" 
 
 #define  URIFilename_filename_DOC "filename($self)\n--\n\nURIFilename.filename() -> str\n\n" \
 "Returns the filename.\n" 

src/vfs.c

@@ -639,6 +639,9 @@ apswvfs_xOpen(sqlite3_vfs *vfs, const char *zName, sqlite3_file *file, int infla
   PyObject *vargs[] = {NULL, (PyObject *)(vfs->pAppData), nameobject, flags};
   if (vargs[2] && vargs[3])
     pyresult = PyObject_VectorcallMethod(apst.xOpen, vargs + 1, 3 | PY_VECTORCALL_ARGUMENTS_OFFSET, NULL);
+  /* issue 501 */
+  if (inflags & (SQLITE_OPEN_URI | SQLITE_OPEN_MAIN_DB))
+    ((APSWURIFilename *)nameobject)->filename = 0;
   if (!pyresult)
   {
     result = MakeSqliteMsgFromPyException(NULL);
@@ -3031,16 +3034,26 @@ static PyTypeObject APSWVFSFileType =
     or the main database flag is set.
 
     You can safely pass it on to the :class:`VFSFile` constructor
-    which knows how to get the name back out.
+    which knows how to get the name back out.  The URIFilename is
+    only valid for the duration of the xOpen call.  If you save
+    and use the object later you will get an exception.
 */
 
+#define CHECK_SCOPE                                                         \
+  do                                                                        \
+  {                                                                         \
+    if (!self->filename)                                                    \
+      return PyErr_Format(PyExc_ValueError, "URIFilename is out of scope"); \
+  } while (0)
+
 /** .. method:: filename() -> str
 
     Returns the filename.
 */
 static PyObject *
 apswurifilename_filename(APSWURIFilename *self)
 {
+  CHECK_SCOPE;
   return convertutf8string(self->filename);
 }
 
@@ -3054,6 +3067,7 @@ apswurifilename_filename(APSWURIFilename *self)
 static PyObject *
 apswurifilename_parameters(APSWURIFilename *self)
 {
+  CHECK_SCOPE;
   int i, count = 0;
   for (i = 0;; i++)
     if (!sqlite3_uri_key(self->filename, i))
@@ -3088,6 +3102,7 @@ apswurifilename_parameters(APSWURIFilename *self)
 static PyObject *
 apswurifilename_uri_parameter(APSWURIFilename *self, PyObject *const *fast_args, Py_ssize_t fast_nargs, PyObject *fast_kwnames)
 {
+  CHECK_SCOPE;
   const char *res, *name;
   {
     URIFilename_uri_parameter_CHECK;
@@ -3109,6 +3124,7 @@ apswurifilename_uri_parameter(APSWURIFilename *self, PyObject *const *fast_args,
 static PyObject *
 apswurifilename_uri_int(APSWURIFilename *self, PyObject *const *fast_args, Py_ssize_t fast_nargs, PyObject *fast_kwnames)
 {
+  CHECK_SCOPE;
   const char *name = NULL;
   long long res = 0, default_;
 
@@ -3134,6 +3150,7 @@ apswurifilename_uri_int(APSWURIFilename *self, PyObject *const *fast_args, Py_ss
 static PyObject *
 apswurifilename_uri_boolean(APSWURIFilename *self, PyObject *const *fast_args, Py_ssize_t fast_nargs, PyObject *fast_kwnames)
 {
+  CHECK_SCOPE;
   const char *name = NULL;
   int default_ = 0, res;
 
@@ -3155,6 +3172,9 @@ apswurifilename_uri_boolean(APSWURIFilename *self, PyObject *const *fast_args, P
 static PyObject *
 apswurifilename_tp_str(APSWURIFilename *self)
 {
+  /* CHECK_SCOPE not needed since we manually check */
+  if (!self->filename)
+    return PyUnicode_FromFormat("<apsw.URIFilename object (out of scope) at %p>", self);
   return PyUnicode_FromFormat("<apsw.URIFilename object \"%s\" at %p>", self->filename, self);
 }
 
@@ -3182,3 +3202,5 @@ static PyTypeObject APSWURIFilenameType =
         .tp_str = (reprfunc)apswurifilename_tp_str,
         .tp_getset = APSWURIFilename_getset,
 };
+
+#undef CHECK_SCOPE