Invalidate iterator if its data is deleted

This removes another potential segfault. Requires swig >= 4.4

Author: jim-easterbrook

src/interface/shared/containers.i

@@ -35,6 +35,7 @@
     base_class::__setitem__;
 %feature("python:slot", "sq_contains", functype="objobjproc")
     base_class::__contains__;
+%typemap(in, numinputs=0) PyObject* py_self {$1 = self;}
 %extend base_class {
     %fragment("get_type_id"{datum_type});
     %fragment("set_value_from_py"{datum_type});
@@ -60,12 +61,19 @@
         datum_type* datum = &(*$self)[key];
         return set_value_from_py(datum, py_value);
     }
+#if SWIG_VERSION >= 0x040400
+    PyObject* __setitem__(PyObject* py_self, const std::string& key) {
+#else
     PyObject* __setitem__(const std::string& key) {
+#endif
         base_class::iterator pos = $self->findKey(key_type(key));
         if (pos == $self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+#if SWIG_VERSION >= 0x040400
+        invalidate_iterators(py_self, pos, pos);
+#endif
         $self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_27_7/exif_wrap.cxx

@@ -5565,11 +5565,15 @@ SWIGINTERN PyObject *Exiv2_ExifData___setitem____SWIG_2(Exiv2::ExifData *self,st
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_ExifData___setitem____SWIG_3(Exiv2::ExifData *self,std::string const &key){
+
         Exiv2::ExifData::iterator pos = self->findKey(Exiv2::ExifKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_27_7/iptc_wrap.cxx

@@ -5505,11 +5505,15 @@ SWIGINTERN PyObject *Exiv2_IptcData___setitem____SWIG_2(Exiv2::IptcData *self,st
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_IptcData___setitem____SWIG_3(Exiv2::IptcData *self,std::string const &key){
+
         Exiv2::IptcData::iterator pos = self->findKey(Exiv2::IptcKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_27_7/xmp_wrap.cxx

@@ -5453,11 +5453,15 @@ SWIGINTERN PyObject *Exiv2_XmpData___setitem____SWIG_2(Exiv2::XmpData *self,std:
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_XmpData___setitem____SWIG_3(Exiv2::XmpData *self,std::string const &key){
+
         Exiv2::XmpData::iterator pos = self->findKey(Exiv2::XmpKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_28_5/exif_wrap.cxx

@@ -5668,11 +5668,15 @@ SWIGINTERN PyObject *Exiv2_ExifData___setitem____SWIG_2(Exiv2::ExifData *self,st
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_ExifData___setitem____SWIG_3(Exiv2::ExifData *self,std::string const &key){
+
         Exiv2::ExifData::iterator pos = self->findKey(Exiv2::ExifKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_28_5/iptc_wrap.cxx

@@ -5615,11 +5615,15 @@ SWIGINTERN PyObject *Exiv2_IptcData___setitem____SWIG_2(Exiv2::IptcData *self,st
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_IptcData___setitem____SWIG_3(Exiv2::IptcData *self,std::string const &key){
+
         Exiv2::IptcData::iterator pos = self->findKey(Exiv2::IptcKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

src/swig-0_28_5/xmp_wrap.cxx

@@ -5615,11 +5615,15 @@ SWIGINTERN PyObject *Exiv2_XmpData___setitem____SWIG_2(Exiv2::XmpData *self,std:
         return set_value_from_py(datum, py_value);
     }
 SWIGINTERN PyObject *Exiv2_XmpData___setitem____SWIG_3(Exiv2::XmpData *self,std::string const &key){
+
         Exiv2::XmpData::iterator pos = self->findKey(Exiv2::XmpKey(key));
         if (pos == self->end()) {
             PyErr_SetString(PyExc_KeyError, key.c_str());
             return NULL;
         }
+
+
+
         self->erase(pos);
         return SWIG_Py_Void();
     }

tests/test_exif.py

@@ -104,8 +104,13 @@ def test_ExifData(self):
         # access by key
         self.assertEqual('Exif.Image.Artist' in data, True)
         self.assertIsInstance(data['Exif.Image.Artist'], exiv2.Exifdatum)
+        k = data.findKey(exiv2.ExifKey('Exif.Image.Artist'))
         del data['Exif.Image.Artist']
         self.assertEqual('Exif.Image.Artist' in data, False)
+        if 'iterators' in data._private_data_:
+            # swig >= 4.4
+            with self.assertRaises(RuntimeError):
+                k.key()
         data['Exif.Image.Artist'] = 'Fred'
         self.assertEqual('Exif.Image.Artist' in data, True)
         self.assertIsInstance(data['Exif.Image.Artist'], exiv2.Exifdatum)