simplify error handling

Author: picnixz

Modules/posixmodule.c

@@ -7292,7 +7292,7 @@ parse_envlist(PyObject* env, Py_ssize_t *envc_ptr)
 {
     Py_ssize_t i, pos, envc;
     PyObject *keys = NULL, *vals = NULL;
-    PyObject *key, *val, *key2, *val2, *keyval;
+    PyObject *key = NULL, *val = NULL, *key2 = NULL, *val2 = NULL;
     EXECV_CHAR **envlist;
 
     i = PyMapping_Size(env);
@@ -7332,14 +7332,9 @@ parse_envlist(PyObject* env, Py_ssize_t *envc_ptr)
 
 #if defined(HAVE_WEXECV) || defined(HAVE_WSPAWNV)
         if (!PyUnicode_FSDecoder(key, &key2)) {
-            Py_DECREF(key);
-            Py_DECREF(val);
             goto error;
         }
         if (!PyUnicode_FSDecoder(val, &val2)) {
-            Py_DECREF(key);
-            Py_DECREF(val);
-            Py_DECREF(key2);
             goto error;
         }
         /* Search from index 1 because on Windows starting '=' is allowed for
@@ -7348,50 +7343,38 @@ parse_envlist(PyObject* env, Py_ssize_t *envc_ptr)
             PyUnicode_FindChar(key2, '=', 1, PyUnicode_GET_LENGTH(key2), 1) != -1)
         {
             PyErr_SetString(PyExc_ValueError, "illegal environment variable name");
-            Py_DECREF(key);
-            Py_DECREF(val);
-            Py_DECREF(key2);
-            Py_DECREF(val2);
             goto error;
         }
-        keyval = PyUnicode_FromFormat("%U=%U", key2, val2);
+        PyObject *keyval = PyUnicode_FromFormat("%U=%U", key2, val2);
 #else
         if (!PyUnicode_FSConverter(key, &key2)) {
-            Py_DECREF(key);
-            Py_DECREF(val);
             goto error;
         }
         if (!PyUnicode_FSConverter(val, &val2)) {
-            Py_DECREF(key);
-            Py_DECREF(val);
-            Py_DECREF(key2);
             goto error;
         }
         if (PyBytes_GET_SIZE(key2) == 0 ||
             strchr(PyBytes_AS_STRING(key2) + 1, '=') != NULL)
         {
             PyErr_SetString(PyExc_ValueError, "illegal environment variable name");
-            Py_DECREF(key);
-            Py_DECREF(val);
-            Py_DECREF(key2);
-            Py_DECREF(val2);
             goto error;
         }
-        keyval = PyBytes_FromFormat("%s=%s", PyBytes_AS_STRING(key2),
-                                             PyBytes_AS_STRING(val2));
-#endif
-        Py_DECREF(key);
-        Py_DECREF(val);
-        Py_DECREF(key2);
-        Py_DECREF(val2);
-        if (!keyval)
+        PyObject *keyval = PyBytes_FromFormat("%s=%s", PyBytes_AS_STRING(key2),
+                                              PyBytes_AS_STRING(val2));
+#endif
+        if (!keyval) {
             goto error;
+        }
 
         if (!fsconvert_strdup(keyval, &envlist[envc++])) {
             Py_DECREF(keyval);
             goto error;
         }
 
+        Py_CLEAR(key);
+        Py_CLEAR(val);
+        Py_CLEAR(key2);
+        Py_CLEAR(val2);
         Py_DECREF(keyval);
     }
     Py_DECREF(vals);
@@ -7402,6 +7385,10 @@ parse_envlist(PyObject* env, Py_ssize_t *envc_ptr)
     return envlist;
 
 error:
+    Py_XDECREF(key);
+    Py_XDECREF(val);
+    Py_XDECREF(key2);
+    Py_XDECREF(val2);
     Py_XDECREF(keys);
     Py_XDECREF(vals);
     free_string_array(envlist, envc);