hw/arm/virt: parameter passing cleanups
[qemu.git] / qapi / qmp-dispatch.c
1 /*
2 * Core Definitions for QAPI/QMP Dispatch
3 *
4 * Copyright IBM, Corp. 2011
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
10 * See the COPYING.LIB file in the top-level directory.
11 *
12 */
13
14 #include "qemu/osdep.h"
15 #include "qapi/error.h"
16 #include "qapi/qmp/types.h"
17 #include "qapi/qmp/dispatch.h"
18 #include "qapi/qmp/json-parser.h"
19 #include "qapi/qmp/qjson.h"
20 #include "qapi-types.h"
21 #include "qapi/qmp/qerror.h"
22
23 static QDict *qmp_dispatch_check_obj(const QObject *request, Error **errp)
24 {
25 const QDictEntry *ent;
26 const char *arg_name;
27 const QObject *arg_obj;
28 bool has_exec_key = false;
29 QDict *dict = NULL;
30
31 if (qobject_type(request) != QTYPE_QDICT) {
32 error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT,
33 "request is not a dictionary");
34 return NULL;
35 }
36
37 dict = qobject_to_qdict(request);
38
39 for (ent = qdict_first(dict); ent;
40 ent = qdict_next(dict, ent)) {
41 arg_name = qdict_entry_key(ent);
42 arg_obj = qdict_entry_value(ent);
43
44 if (!strcmp(arg_name, "execute")) {
45 if (qobject_type(arg_obj) != QTYPE_QSTRING) {
46 error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT_MEMBER, "execute",
47 "string");
48 return NULL;
49 }
50 has_exec_key = true;
51 } else if (strcmp(arg_name, "arguments")) {
52 error_setg(errp, QERR_QMP_EXTRA_MEMBER, arg_name);
53 return NULL;
54 }
55 }
56
57 if (!has_exec_key) {
58 error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT, "execute");
59 return NULL;
60 }
61
62 return dict;
63 }
64
65 static QObject *do_qmp_dispatch(QObject *request, Error **errp)
66 {
67 Error *local_err = NULL;
68 const char *command;
69 QDict *args, *dict;
70 QmpCommand *cmd;
71 QObject *ret = NULL;
72
73 dict = qmp_dispatch_check_obj(request, errp);
74 if (!dict) {
75 return NULL;
76 }
77
78 command = qdict_get_str(dict, "execute");
79 cmd = qmp_find_command(command);
80 if (cmd == NULL) {
81 error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
82 "The command %s has not been found", command);
83 return NULL;
84 }
85 if (!cmd->enabled) {
86 error_setg(errp, "The command %s has been disabled for this instance",
87 command);
88 return NULL;
89 }
90
91 if (!qdict_haskey(dict, "arguments")) {
92 args = qdict_new();
93 } else {
94 args = qdict_get_qdict(dict, "arguments");
95 QINCREF(args);
96 }
97
98 cmd->fn(args, &ret, &local_err);
99 if (local_err) {
100 error_propagate(errp, local_err);
101 } else if (cmd->options & QCO_NO_SUCCESS_RESP) {
102 g_assert(!ret);
103 } else if (!ret) {
104 ret = QOBJECT(qdict_new());
105 }
106
107 QDECREF(args);
108
109 return ret;
110 }
111
112 QObject *qmp_build_error_object(Error *err)
113 {
114 return qobject_from_jsonf("{ 'class': %s, 'desc': %s }",
115 QapiErrorClass_lookup[error_get_class(err)],
116 error_get_pretty(err));
117 }
118
119 QObject *qmp_dispatch(QObject *request)
120 {
121 Error *err = NULL;
122 QObject *ret;
123 QDict *rsp;
124
125 ret = do_qmp_dispatch(request, &err);
126
127 rsp = qdict_new();
128 if (err) {
129 qdict_put_obj(rsp, "error", qmp_build_error_object(err));
130 error_free(err);
131 } else if (ret) {
132 qdict_put_obj(rsp, "return", ret);
133 } else {
134 QDECREF(rsp);
135 return NULL;
136 }
137
138 return QOBJECT(rsp);
139 }