xref: /openbmc/qemu/qapi/qmp-dispatch.c (revision 39164c13)
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     dict = qobject_to_qdict(request);
32     if (!dict) {
33         error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT,
34                    "request is not a dictionary");
35         return NULL;
36     }
37 
38     for (ent = qdict_first(dict); ent;
39          ent = qdict_next(dict, ent)) {
40         arg_name = qdict_entry_key(ent);
41         arg_obj = qdict_entry_value(ent);
42 
43         if (!strcmp(arg_name, "execute")) {
44             if (qobject_type(arg_obj) != QTYPE_QSTRING) {
45                 error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT_MEMBER, "execute",
46                            "string");
47                 return NULL;
48             }
49             has_exec_key = true;
50         } else if (strcmp(arg_name, "arguments")) {
51             error_setg(errp, QERR_QMP_EXTRA_MEMBER, arg_name);
52             return NULL;
53         }
54     }
55 
56     if (!has_exec_key) {
57         error_setg(errp, QERR_QMP_BAD_INPUT_OBJECT, "execute");
58         return NULL;
59     }
60 
61     return dict;
62 }
63 
64 static QObject *do_qmp_dispatch(QObject *request, Error **errp)
65 {
66     Error *local_err = NULL;
67     const char *command;
68     QDict *args, *dict;
69     QmpCommand *cmd;
70     QObject *ret = NULL;
71 
72     dict = qmp_dispatch_check_obj(request, errp);
73     if (!dict) {
74         return NULL;
75     }
76 
77     command = qdict_get_str(dict, "execute");
78     cmd = qmp_find_command(command);
79     if (cmd == NULL) {
80         error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
81                   "The command %s has not been found", command);
82         return NULL;
83     }
84     if (!cmd->enabled) {
85         error_setg(errp, "The command %s has been disabled for this instance",
86                    command);
87         return NULL;
88     }
89 
90     if (!qdict_haskey(dict, "arguments")) {
91         args = qdict_new();
92     } else {
93         args = qdict_get_qdict(dict, "arguments");
94         QINCREF(args);
95     }
96 
97     cmd->fn(args, &ret, &local_err);
98     if (local_err) {
99         error_propagate(errp, local_err);
100     } else if (cmd->options & QCO_NO_SUCCESS_RESP) {
101         g_assert(!ret);
102     } else if (!ret) {
103         ret = QOBJECT(qdict_new());
104     }
105 
106     QDECREF(args);
107 
108     return ret;
109 }
110 
111 QObject *qmp_build_error_object(Error *err)
112 {
113     return qobject_from_jsonf("{ 'class': %s, 'desc': %s }",
114                               QapiErrorClass_lookup[error_get_class(err)],
115                               error_get_pretty(err));
116 }
117 
118 QObject *qmp_dispatch(QObject *request)
119 {
120     Error *err = NULL;
121     QObject *ret;
122     QDict *rsp;
123 
124     ret = do_qmp_dispatch(request, &err);
125 
126     rsp = qdict_new();
127     if (err) {
128         qdict_put_obj(rsp, "error", qmp_build_error_object(err));
129         error_free(err);
130     } else if (ret) {
131         qdict_put_obj(rsp, "return", ret);
132     } else {
133         QDECREF(rsp);
134         return NULL;
135     }
136 
137     return QOBJECT(rsp);
138 }
139