qapi: Consistent generated code: prefer error 'err'

We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch consistently names the local error variable 'err' rather
than 'local_err'.

No change in semantics to the generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

docs/qapi-code-gen.txt

@@ -916,20 +916,20 @@ Example:
 
     static void qmp_marshal_output_UserDefOne(UserDefOne *ret_in, QObject **ret_out, Error **errp)
     {
-        Error *local_err = NULL;
+        Error *err = NULL;
         QmpOutputVisitor *mo = qmp_output_visitor_new();
         QapiDeallocVisitor *md;
         Visitor *v;
 
         v = qmp_output_get_visitor(mo);
-        visit_type_UserDefOne(v, &ret_in, "unused", &local_err);
+        visit_type_UserDefOne(v, &ret_in, "unused", &err);
-        if (local_err) {
+        if (err) {
             goto out;
         }
         *ret_out = qmp_output_get_qobject(mo);
 
     out:
-        error_propagate(errp, local_err);
+        error_propagate(errp, err);
         qmp_output_visitor_cleanup(mo);
         md = qapi_dealloc_visitor_new();
         v = qapi_dealloc_get_visitor(md);
@@ -939,7 +939,7 @@ Example:
 
     static void qmp_marshal_my_command(QDict *args, QObject **ret, Error **errp)
     {
-        Error *local_err = NULL;
+        Error *err = NULL;
         UserDefOne *retval;
         QmpInputVisitor *mi = qmp_input_visitor_new_strict(QOBJECT(args));
         QapiDeallocVisitor *md;
@@ -947,20 +947,20 @@ Example:
         UserDefOne *arg1 = NULL;
 
         v = qmp_input_get_visitor(mi);
-        visit_type_UserDefOne(v, &arg1, "arg1", &local_err);
+        visit_type_UserDefOne(v, &arg1, "arg1", &err);
-        if (local_err) {
+        if (err) {
             goto out;
         }
 
-        retval = qmp_my_command(arg1, &local_err);
+        retval = qmp_my_command(arg1, &err);
-        if (local_err) {
+        if (err) {
             goto out;
         }
 
-        qmp_marshal_output_UserDefOne(retval, ret, &local_err);
+        qmp_marshal_output_UserDefOne(retval, ret, &err);
 
     out:
-        error_propagate(errp, local_err);
+        error_propagate(errp, err);
         qmp_input_visitor_cleanup(mi);
         md = qapi_dealloc_visitor_new();
         v = qapi_dealloc_get_visitor(md);
@@ -1007,7 +1007,7 @@ Example:
     void qapi_event_send_my_event(Error **errp)
     {
         QDict *qmp;
-        Error *local_err = NULL;
+        Error *err = NULL;
         QMPEventFuncEmit emit;
         emit = qmp_event_get_func_emit();
         if (!emit) {
@@ -1016,9 +1016,9 @@ Example:
 
         qmp = qmp_event_build_dict("MY_EVENT");
 
-        emit(EXAMPLE_QAPI_EVENT_MY_EVENT, qmp, &local_err);
+        emit(EXAMPLE_QAPI_EVENT_MY_EVENT, qmp, &err);
 
-        error_propagate(errp, local_err);
+        error_propagate(errp, err);
         QDECREF(qmp);
     }
 

scripts/qapi-commands.py

@@ -53,14 +53,14 @@ def gen_call(name, arg_type, ret_type):
     push_indent()
     ret = mcgen('''
 
-%(lhs)sqmp_%(c_name)s(%(args)s&local_err);
+%(lhs)sqmp_%(c_name)s(%(args)s&err);
 ''',
                 c_name=c_name(name), args=argstr, lhs=lhs)
     if ret_type:
-        ret += gen_err_check('local_err')
+        ret += gen_err_check('err')
         ret += mcgen('''
 
-qmp_marshal_output_%(c_name)s(retval, ret, &local_err);
+qmp_marshal_output_%(c_name)s(retval, ret, &err);
 ''',
                      c_name=ret_type.c_name())
     pop_indent()
@@ -69,7 +69,7 @@ def gen_call(name, arg_type, ret_type):
 
 def gen_marshal_vars(arg_type, ret_type):
     ret = mcgen('''
-    Error *local_err = NULL;
+    Error *err = NULL;
 ''')
 
     push_indent()
@@ -127,8 +127,8 @@ def gen_marshal_input_visit(arg_type, dealloc=False):
 v = qapi_dealloc_get_visitor(md);
 ''')
     else:
-        errparg = '&local_err'
+        errparg = '&err'
-        errarg = 'local_err'
+        errarg = 'err'
         ret += mcgen('''
 v = qmp_input_get_visitor(mi);
 ''')
@@ -171,20 +171,20 @@ def gen_marshal_output(ret_type):
 
 static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
 {
-    Error *local_err = NULL;
+    Error *err = NULL;
     QmpOutputVisitor *mo = qmp_output_visitor_new();
     QapiDeallocVisitor *md;
     Visitor *v;
 
     v = qmp_output_get_visitor(mo);
-    visit_type_%(c_name)s(v, &ret_in, "unused", &local_err);
+    visit_type_%(c_name)s(v, &ret_in, "unused", &err);
-    if (local_err) {
+    if (err) {
         goto out;
     }
     *ret_out = qmp_output_get_qobject(mo);
 
 out:
-    error_propagate(errp, local_err);
+    error_propagate(errp, err);
     qmp_output_visitor_cleanup(mo);
     md = qapi_dealloc_visitor_new();
     v = qapi_dealloc_get_visitor(md);
@@ -227,7 +227,7 @@ def gen_marshal(name, arg_type, ret_type):
 out:
 ''')
     ret += mcgen('''
-    error_propagate(errp, local_err);
+    error_propagate(errp, err);
 ''')
     ret += gen_marshal_input_visit(arg_type, dealloc=True)
     ret += mcgen('''

scripts/qapi-event.py

@@ -34,7 +34,7 @@ def gen_event_send(name, arg_type):
 %(proto)s
 {
     QDict *qmp;
-    Error *local_err = NULL;
+    Error *err = NULL;
     QMPEventFuncEmit emit;
 ''',
                 proto=gen_event_send_proto(name, arg_type))
@@ -67,8 +67,8 @@ def gen_event_send(name, arg_type):
     g_assert(v);
 
     /* Fake visit, as if all members are under a structure */
-    visit_start_struct(v, NULL, "", "%(name)s", 0, &local_err);
+    visit_start_struct(v, NULL, "", "%(name)s", 0, &err);
-    if (local_err) {
+    if (err) {
         goto clean;
     }
 
@@ -90,8 +90,8 @@ def gen_event_send(name, arg_type):
                 cast = ''
 
             ret += mcgen('''
-    visit_type_%(c_type)s(v, %(cast)s&%(c_name)s, "%(name)s", &local_err);
+    visit_type_%(c_type)s(v, %(cast)s&%(c_name)s, "%(name)s", &err);
-    if (local_err) {
+    if (err) {
         goto clean;
     }
 ''',
@@ -108,8 +108,8 @@ def gen_event_send(name, arg_type):
 
         ret += mcgen('''
 
-    visit_end_struct(v, &local_err);
+    visit_end_struct(v, &err);
-    if (local_err) {
+    if (err) {
         goto clean;
     }
 
@@ -120,7 +120,7 @@ def gen_event_send(name, arg_type):
 ''')
 
     ret += mcgen('''
-    emit(%(c_enum)s, qmp, &local_err);
+    emit(%(c_enum)s, qmp, &err);
 
 ''',
                  c_enum=c_enum_const(event_enum_name, name))
@@ -131,7 +131,7 @@ def gen_event_send(name, arg_type):
     qmp_output_visitor_cleanup(qov);
 ''')
     ret += mcgen('''
-    error_propagate(errp, local_err);
+    error_propagate(errp, err);
     QDECREF(qmp);
 }
 ''')