xref: /openbmc/qemu/qapi/qmp-dispatch.c (revision 14a650ec)
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 "qapi/qmp/types.h"
15 #include "qapi/qmp/dispatch.h"
16 #include "qapi/qmp/json-parser.h"
17 #include "qapi-types.h"
18 #include "qapi/error.h"
19 #include "qapi/qmp/qerror.h"
20 
21 static QDict *qmp_dispatch_check_obj(const QObject *request, Error **errp)
22 {
23     const QDictEntry *ent;
24     const char *arg_name;
25     const QObject *arg_obj;
26     bool has_exec_key = false;
27     QDict *dict = NULL;
28 
29     if (qobject_type(request) != QTYPE_QDICT) {
30         error_set(errp, QERR_QMP_BAD_INPUT_OBJECT,
31                   "request is not a dictionary");
32         return NULL;
33     }
34 
35     dict = qobject_to_qdict(request);
36 
37     for (ent = qdict_first(dict); ent;
38          ent = qdict_next(dict, ent)) {
39         arg_name = qdict_entry_key(ent);
40         arg_obj = qdict_entry_value(ent);
41 
42         if (!strcmp(arg_name, "execute")) {
43             if (qobject_type(arg_obj) != QTYPE_QSTRING) {
44                 error_set(errp, QERR_QMP_BAD_INPUT_OBJECT_MEMBER, "execute",
45                           "string");
46                 return NULL;
47             }
48             has_exec_key = true;
49         } else if (strcmp(arg_name, "arguments")) {
50             error_set(errp, QERR_QMP_EXTRA_MEMBER, arg_name);
51             return NULL;
52         }
53     }
54 
55     if (!has_exec_key) {
56         error_set(errp, QERR_QMP_BAD_INPUT_OBJECT, "execute");
57         return NULL;
58     }
59 
60     return dict;
61 }
62 
63 static QObject *do_qmp_dispatch(QObject *request, Error **errp)
64 {
65     const char *command;
66     QDict *args, *dict;
67     QmpCommand *cmd;
68     QObject *ret = NULL;
69 
70 
71     dict = qmp_dispatch_check_obj(request, errp);
72     if (!dict || error_is_set(errp)) {
73         return NULL;
74     }
75 
76     command = qdict_get_str(dict, "execute");
77     cmd = qmp_find_command(command);
78     if (cmd == NULL) {
79         error_set(errp, QERR_COMMAND_NOT_FOUND, command);
80         return NULL;
81     }
82     if (!cmd->enabled) {
83         error_set(errp, QERR_COMMAND_DISABLED, command);
84         return NULL;
85     }
86 
87     if (!qdict_haskey(dict, "arguments")) {
88         args = qdict_new();
89     } else {
90         args = qdict_get_qdict(dict, "arguments");
91         QINCREF(args);
92     }
93 
94     switch (cmd->type) {
95     case QCT_NORMAL:
96         cmd->fn(args, &ret, errp);
97         if (!error_is_set(errp)) {
98             if (cmd->options & QCO_NO_SUCCESS_RESP) {
99                 g_assert(!ret);
100             } else if (!ret) {
101                 ret = QOBJECT(qdict_new());
102             }
103         }
104         break;
105     }
106 
107     QDECREF(args);
108 
109     return ret;
110 }
111 
112 QObject *qmp_build_error_object(Error *errp)
113 {
114     return qobject_from_jsonf("{ 'class': %s, 'desc': %s }",
115                               ErrorClass_lookup[error_get_class(errp)],
116                               error_get_pretty(errp));
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 }
140