bpo-32788: Better error handling in sqlite3. (GH-3723)

Propagate unexpected errors (like MemoryError and KeyboardInterrupt) to user.

5 files changed, 128 insertions, 121 deletions

diff --git a/Modules/_sqlite/cache.c b/Modules/_sqlite/cache.c
index 72b1f2c..4270473 100644
--- a/Modules/_sqlite/cache.c
+++ b/Modules/_sqlite/cache.c
@@ -119,7 +119,7 @@ PyObject* pysqlite_cache_get(pysqlite_Cache* self, PyObject* args)
     pysqlite_Node* ptr;
     PyObject* data;
 
-    node = (pysqlite_Node*)PyDict_GetItem(self->mapping, key);
+    node = (pysqlite_Node*)PyDict_GetItemWithError(self->mapping, key);
     if (node) {
         /* an entry for this key already exists in the cache */
 
@@ -157,7 +157,11 @@ PyObject* pysqlite_cache_get(pysqlite_Cache* self, PyObject* args)
             }
             ptr->prev = node;
         }
-    } else {
+    }
+    else if (PyErr_Occurred()) {
+        return NULL;
+    }
+    else {
         /* There is no entry for this key in the cache, yet. We'll insert a new
          * entry in the cache, and make space if necessary by throwing the
          * least used item out of the cache. */
diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
index fe0d03b..aab4b1a 100644
--- a/Modules/_sqlite/connection.c
+++ b/Modules/_sqlite/connection.c
@@ -1432,6 +1432,7 @@ finally:
 static PyObject *
 pysqlite_connection_iterdump(pysqlite_Connection* self, PyObject* args)
 {
+    _Py_IDENTIFIER(_iterdump);
     PyObject* retval = NULL;
     PyObject* module = NULL;
     PyObject* module_dict;
@@ -1451,9 +1452,12 @@ pysqlite_connection_iterdump(pysqlite_Connection* self, PyObject* args)
         goto finally;
     }
 
-    pyfn_iterdump = PyDict_GetItemString(module_dict, "_iterdump");
+    pyfn_iterdump = _PyDict_GetItemIdWithError(module_dict, &PyId__iterdump);
     if (!pyfn_iterdump) {
-        PyErr_SetString(pysqlite_OperationalError, "Failed to obtain _iterdump() reference");
+        if (!PyErr_Occurred()) {
+            PyErr_SetString(pysqlite_OperationalError,
+                            "Failed to obtain _iterdump() reference");
+        }
         goto finally;
     }
 
diff --git a/Modules/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
index 8a46e5c..2bc1931 100644
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -94,40 +94,47 @@ static void pysqlite_cursor_dealloc(pysqlite_Cursor* self)
     Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
-PyObject* _pysqlite_get_converter(PyObject* key)
+static PyObject *
+_pysqlite_get_converter(const char *keystr, Py_ssize_t keylen)
 {
-    PyObject* upcase_key;
-    PyObject* retval;
+    PyObject *key;
+    PyObject *upcase_key;
+    PyObject *retval;
     _Py_IDENTIFIER(upper);
 
+    key = PyUnicode_FromStringAndSize(keystr, keylen);
+    if (!key) {
+        return NULL;
+    }
     upcase_key = _PyObject_CallMethodId(key, &PyId_upper, NULL);
+    Py_DECREF(key);
     if (!upcase_key) {
         return NULL;
     }
 
-    retval = PyDict_GetItem(_pysqlite_converters, upcase_key);
+    retval = PyDict_GetItemWithError(_pysqlite_converters, upcase_key);
     Py_DECREF(upcase_key);
 
     return retval;
 }
 
-int pysqlite_build_row_cast_map(pysqlite_Cursor* self)
+static int
+pysqlite_build_row_cast_map(pysqlite_Cursor* self)
 {
     int i;
-    const char* type_start = (const char*)-1;
     const char* pos;
-
     const char* colname;
     const char* decltype;
-    PyObject* py_decltype;
     PyObject* converter;
-    PyObject* key;
 
     if (!self->connection->detect_types) {
         return 0;
     }
 
     Py_XSETREF(self->row_cast_map, PyList_New(0));
+    if (!self->row_cast_map) {
+        return -1;
+    }
 
     for (i = 0; i < sqlite3_column_count(self->statement->st); i++) {
         converter = NULL;
@@ -135,20 +142,17 @@ int pysqlite_build_row_cast_map(pysqlite_Cursor* self)
         if (self->connection->detect_types & PARSE_COLNAMES) {
             colname = sqlite3_column_name(self->statement->st, i);
             if (colname) {
+                const char *type_start = NULL;
                 for (pos = colname; *pos != 0; pos++) {
                     if (*pos == '[') {
                         type_start = pos + 1;
-                    } else if (*pos == ']' && type_start != (const char*)-1) {
-                        key = PyUnicode_FromStringAndSize(type_start, pos - type_start);
-                        if (!key) {
-                            /* creating a string failed, but it is too complicated
-                             * to propagate the error here, we just assume there is
-                             * no converter and proceed */
-                            break;
+                    }
+                    else if (*pos == ']' && type_start != NULL) {
+                        converter = _pysqlite_get_converter(type_start, pos - type_start);
+                        if (!converter && PyErr_Occurred()) {
+                            Py_CLEAR(self->row_cast_map);
+                            return -1;
                         }
-
-                        converter = _pysqlite_get_converter(key);
-                        Py_DECREF(key);
                         break;
                     }
                 }
@@ -164,16 +168,14 @@ int pysqlite_build_row_cast_map(pysqlite_Cursor* self)
                      * 'NUMBER(10)' to be treated as 'NUMBER', for example.
                      * In other words, it will work as people expect it to work.*/
                     if (*pos == ' ' || *pos == '(' || *pos == 0) {
-                        py_decltype = PyUnicode_FromStringAndSize(decltype, pos - decltype);
-                        if (!py_decltype) {
+                        converter = _pysqlite_get_converter(decltype, pos - decltype);
+                        if (!converter && PyErr_Occurred()) {
+                            Py_CLEAR(self->row_cast_map);
                             return -1;
                         }
                         break;
                     }
                 }
-
-                converter = _pysqlite_get_converter(py_decltype);
-                Py_DECREF(py_decltype);
             }
         }
 
@@ -182,11 +184,7 @@ int pysqlite_build_row_cast_map(pysqlite_Cursor* self)
         }
 
         if (PyList_Append(self->row_cast_map, converter) != 0) {
-            if (converter != Py_None) {
-                Py_DECREF(converter);
-            }
             Py_CLEAR(self->row_cast_map);
-
             return -1;
         }
     }
@@ -194,7 +192,8 @@ int pysqlite_build_row_cast_map(pysqlite_Cursor* self)
     return 0;
 }
 
-PyObject* _pysqlite_build_column_name(const char* colname)
+static PyObject *
+_pysqlite_build_column_name(const char* colname)
 {
     const char* pos;
 
@@ -218,7 +217,8 @@ PyObject* _pysqlite_build_column_name(const char* colname)
  * Precondidition:
  * - sqlite3_step() has been called before and it returned SQLITE_ROW.
  */
-PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
+static PyObject *
+_pysqlite_fetch_one_row(pysqlite_Cursor* self)
 {
     int i, numcols;
     PyObject* row;
@@ -227,12 +227,10 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
     PyObject* converter;
     PyObject* converted;
     Py_ssize_t nbytes;
-    PyObject* buffer;
     const char* val_str;
     char buf[200];
     const char* colname;
-    PyObject* buf_bytes;
-    PyObject* error_obj;
+    PyObject* error_msg;
 
     if (self->reset) {
         PyErr_SetString(pysqlite_InterfaceError, errmsg_fetch_across_rollback);
@@ -248,13 +246,13 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
         return NULL;
 
     for (i = 0; i < numcols; i++) {
-        if (self->connection->detect_types) {
-            assert(self->row_cast_map != NULL);
-            converter = PyList_GetItem(self->row_cast_map, i);
-            if (!converter) {
-                converter = Py_None;
-            }
-        } else {
+        if (self->connection->detect_types
+                && self->row_cast_map != NULL
+                && i < PyList_GET_SIZE(self->row_cast_map))
+        {
+            converter = PyList_GET_ITEM(self->row_cast_map, i);
+        }
+        else {
             converter = Py_None;
         }
 
@@ -270,8 +268,6 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
                     goto error;
                 converted = PyObject_CallFunction(converter, "O", item);
                 Py_DECREF(item);
-                if (!converted)
-                    break;
             }
         } else {
             Py_BEGIN_ALLOW_THREADS
@@ -289,7 +285,7 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
                 nbytes = sqlite3_column_bytes(self->statement->st, i);
                 if (self->connection->text_factory == (PyObject*)&PyUnicode_Type) {
                     converted = PyUnicode_FromStringAndSize(val_str, nbytes);
-                    if (!converted) {
+                    if (!converted && PyErr_ExceptionMatches(PyExc_UnicodeDecodeError)) {
                         PyErr_Clear();
                         colname = sqlite3_column_name(self->statement->st, i);
                         if (!colname) {
@@ -297,18 +293,12 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
                         }
                         PyOS_snprintf(buf, sizeof(buf) - 1, "Could not decode to UTF-8 column '%s' with text '%s'",
                                      colname , val_str);
-                        buf_bytes = PyByteArray_FromStringAndSize(buf, strlen(buf));
-                        if (!buf_bytes) {
+                        error_msg = PyUnicode_Decode(buf, strlen(buf), "ascii", "replace");
+                        if (!error_msg) {
                             PyErr_SetString(pysqlite_OperationalError, "Could not decode to UTF-8");
                         } else {
-                            error_obj = PyUnicode_FromEncodedObject(buf_bytes, "ascii", "replace");
-                            if (!error_obj) {
-                                PyErr_SetString(pysqlite_OperationalError, "Could not decode to UTF-8");
-                            } else {
-                                PyErr_SetObject(pysqlite_OperationalError, error_obj);
-                                Py_DECREF(error_obj);
-                            }
-                            Py_DECREF(buf_bytes);
+                            PyErr_SetObject(pysqlite_OperationalError, error_msg);
+                            Py_DECREF(error_msg);
                         }
                     }
                 } else if (self->connection->text_factory == (PyObject*)&PyBytes_Type) {
@@ -321,20 +311,15 @@ PyObject* _pysqlite_fetch_one_row(pysqlite_Cursor* self)
             } else {
                 /* coltype == SQLITE_BLOB */
                 nbytes = sqlite3_column_bytes(self->statement->st, i);
-                buffer = PyBytes_FromStringAndSize(
+                converted = PyBytes_FromStringAndSize(
                     sqlite3_column_blob(self->statement->st, i), nbytes);
-                if (!buffer)
-                    break;
-                converted = buffer;
             }
         }
 
-        if (converted) {
-            PyTuple_SetItem(row, i, converted);
-        } else {
-            Py_INCREF(Py_None);
-            PyTuple_SetItem(row, i, Py_None);
+        if (!converted) {
+            goto error;
         }
+        PyTuple_SetItem(row, i, converted);
     }
 
     if (PyErr_Occurred())
@@ -372,7 +357,8 @@ static int check_cursor(pysqlite_Cursor* cur)
     return pysqlite_check_thread(cur->connection) && pysqlite_check_connection(cur->connection);
 }
 
-PyObject* _pysqlite_query_execute(pysqlite_Cursor* self, int multiple, PyObject* args)
+static PyObject *
+_pysqlite_query_execute(pysqlite_Cursor* self, int multiple, PyObject* args)
 {
     PyObject* operation;
     PyObject* parameters_list = NULL;
@@ -542,7 +528,7 @@ PyObject* _pysqlite_query_execute(pysqlite_Cursor* self, int multiple, PyObject*
         }
 
         if (pysqlite_build_row_cast_map(self) != 0) {
-            PyErr_SetString(pysqlite_OperationalError, "Error while building row_cast_map");
+            _PyErr_FormatFromCause(pysqlite_OperationalError, "Error while building row_cast_map");
             goto error;
         }
 
@@ -631,7 +617,8 @@ PyObject* pysqlite_cursor_executemany(pysqlite_Cursor* self, PyObject* args)
     return _pysqlite_query_execute(self, 1, args);
 }
 
-PyObject* pysqlite_cursor_executescript(pysqlite_Cursor* self, PyObject* args)
+static PyObject *
+pysqlite_cursor_executescript(pysqlite_Cursor* self, PyObject* args)
 {
     PyObject* script_obj;
     PyObject* script_str = NULL;
@@ -718,12 +705,6 @@ error:
     }
 }
 
-PyObject* pysqlite_cursor_getiter(pysqlite_Cursor *self)
-{
-    Py_INCREF(self);
-    return (PyObject*)self;
-}
-
 PyObject* pysqlite_cursor_iternext(pysqlite_Cursor *self)
 {
     PyObject* next_row_tuple;
@@ -961,7 +942,7 @@ PyTypeObject pysqlite_CursorType = {
         0,                                              /* tp_clear */
         0,                                              /* tp_richcompare */
         offsetof(pysqlite_Cursor, in_weakreflist),      /* tp_weaklistoffset */
-        (getiterfunc)pysqlite_cursor_getiter,           /* tp_iter */
+        PyObject_SelfIter,                              /* tp_iter */
         (iternextfunc)pysqlite_cursor_iternext,         /* tp_iternext */
         cursor_methods,                                 /* tp_methods */
         cursor_members,                                 /* tp_members */
diff --git a/Modules/_sqlite/microprotocols.c b/Modules/_sqlite/microprotocols.c
index 3d01872..c23b09f 100644
--- a/Modules/_sqlite/microprotocols.c
+++ b/Modules/_sqlite/microprotocols.c
@@ -75,7 +75,9 @@ pysqlite_microprotocols_add(PyTypeObject *type, PyObject *proto, PyObject *cast)
 PyObject *
 pysqlite_microprotocols_adapt(PyObject *obj, PyObject *proto, PyObject *alt)
 {
-    PyObject *adapter, *key;
+    _Py_IDENTIFIER(__adapt__);
+    _Py_IDENTIFIER(__conform__);
+    PyObject *adapter, *key, *adapted;
 
     /* we don't check for exact type conformance as specified in PEP 246
        because the pysqlite_PrepareProtocolType type is abstract and there is no
@@ -86,48 +88,60 @@ pysqlite_microprotocols_adapt(PyObject *obj, PyObject *proto, PyObject *alt)
     if (!key) {
         return NULL;
     }
-    adapter = PyDict_GetItem(psyco_adapters, key);
+    adapter = PyDict_GetItemWithError(psyco_adapters, key);
     Py_DECREF(key);
     if (adapter) {
-        PyObject *adapted = PyObject_CallFunctionObjArgs(adapter, obj, NULL);
+        Py_INCREF(adapter);
+        adapted = PyObject_CallFunctionObjArgs(adapter, obj, NULL);
+        Py_DECREF(adapter);
         return adapted;
     }
+    if (PyErr_Occurred()) {
+        return NULL;
+    }
 
-    /* try to have the protocol adapt this object*/
-    if (PyObject_HasAttrString(proto, "__adapt__")) {
-        _Py_IDENTIFIER(__adapt__);
-        PyObject *adapted = _PyObject_CallMethodId(proto, &PyId___adapt__, "O", obj);
-
-        if (adapted) {
-            if (adapted != Py_None) {
-                return adapted;
-            } else {
-                Py_DECREF(adapted);
-            }
-        }
+    /* try to have the protocol adapt this object */
+    if (_PyObject_LookupAttrId(proto, &PyId___adapt__, &adapter) < 0) {
+        return NULL;
+    }
+    if (adapter) {
+        adapted = PyObject_CallFunctionObjArgs(adapter, obj, NULL);
+        Py_DECREF(adapter);
 
-        if (PyErr_Occurred() && !PyErr_ExceptionMatches(PyExc_TypeError))
-            return NULL;
+        if (adapted == Py_None) {
+            Py_DECREF(adapted);
+        }
+        else if (adapted || !PyErr_ExceptionMatches(PyExc_TypeError)) {
+            return adapted;
+        }
+        else {
+            PyErr_Clear();
+        }
     }
 
     /* and finally try to have the object adapt itself */
-    if (PyObject_HasAttrString(obj, "__conform__")) {
-        _Py_IDENTIFIER(__conform__);
-        PyObject *adapted = _PyObject_CallMethodId(obj, &PyId___conform__,"O", proto);
-
-        if (adapted) {
-            if (adapted != Py_None) {
-                return adapted;
-            } else {
-                Py_DECREF(adapted);
-            }
-        }
+    if (_PyObject_LookupAttrId(obj, &PyId___conform__, &adapter) < 0) {
+        return NULL;
+    }
+    if (adapter) {
+        adapted = PyObject_CallFunctionObjArgs(adapter, proto, NULL);
+        Py_DECREF(adapter);
 
-        if (PyErr_Occurred() && !PyErr_ExceptionMatches(PyExc_TypeError)) {
-            return NULL;
+        if (adapted == Py_None) {
+            Py_DECREF(adapted);
+        }
+        else if (adapted || !PyErr_ExceptionMatches(PyExc_TypeError)) {
+            return adapted;
+        }
+        else {
+            PyErr_Clear();
         }
     }
 
+    if (alt) {
+        Py_INCREF(alt);
+        return alt;
+    }
     /* else set the right exception and return NULL */
     PyErr_SetString(pysqlite_ProgrammingError, "can't adapt");
     return NULL;
diff --git a/Modules/_sqlite/statement.c b/Modules/_sqlite/statement.c
index 78033d8..575ac69 100644
--- a/Modules/_sqlite/statement.c
+++ b/Modules/_sqlite/statement.c
@@ -250,12 +250,10 @@ void pysqlite_statement_bind_parameters(pysqlite_Statement* self, PyObject* para
             if (!_need_adapt(current_param)) {
                 adapted = current_param;
             } else {
-                adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, NULL);
-                if (adapted) {
-                    Py_DECREF(current_param);
-                } else {
-                    PyErr_Clear();
-                    adapted = current_param;
+                adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, current_param);
+                Py_DECREF(current_param);
+                if (!adapted) {
+                    return;
                 }
             }
 
@@ -272,6 +270,7 @@ void pysqlite_statement_bind_parameters(pysqlite_Statement* self, PyObject* para
     } else if (PyDict_Check(parameters)) {
         /* parameters passed as dictionary */
         for (i = 1; i <= num_params_needed; i++) {
+            PyObject *binding_name_obj;
             Py_BEGIN_ALLOW_THREADS
             binding_name = sqlite3_bind_parameter_name(self->st, i);
             Py_END_ALLOW_THREADS
@@ -281,26 +280,31 @@ void pysqlite_statement_bind_parameters(pysqlite_Statement* self, PyObject* para
             }
 
             binding_name++; /* skip first char (the colon) */
+            binding_name_obj = PyUnicode_FromString(binding_name);
+            if (!binding_name_obj) {
+                return;
+            }
             if (PyDict_CheckExact(parameters)) {
-                current_param = PyDict_GetItemString(parameters, binding_name);
+                current_param = PyDict_GetItemWithError(parameters, binding_name_obj);
                 Py_XINCREF(current_param);
             } else {
-                current_param = PyMapping_GetItemString(parameters, binding_name);
+                current_param = PyObject_GetItem(parameters, binding_name_obj);
             }
+            Py_DECREF(binding_name_obj);
             if (!current_param) {
-                PyErr_Format(pysqlite_ProgrammingError, "You did not supply a value for binding %d.", i);
+                if (!PyErr_Occurred() || PyErr_ExceptionMatches(PyExc_LookupError)) {
+                    PyErr_Format(pysqlite_ProgrammingError, "You did not supply a value for binding %d.", i);
+                }
                 return;
             }
 
             if (!_need_adapt(current_param)) {
                 adapted = current_param;
             } else {
-                adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, NULL);
-                if (adapted) {
-                    Py_DECREF(current_param);
-                } else {
-                    PyErr_Clear();
-                    adapted = current_param;
+                adapted = pysqlite_microprotocols_adapt(current_param, (PyObject*)&pysqlite_PrepareProtocolType, current_param);
+                Py_DECREF(current_param);
+                if (!adapted) {
+                    return;
                 }
             }