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/dispatch.h" |
17 | #include "qapi/qmp/qdict.h" |
18 | #include "qapi/qmp/qjson.h" |
19 | #include "sysemu/runstate.h" |
20 | #include "qapi/qmp/qbool.h" |
21 | |
22 | static QDict *qmp_dispatch_check_obj(const QObject *request, bool allow_oob, |
23 | Error **errp) |
24 | { |
25 | const char *exec_key = NULL; |
26 | const QDictEntry *ent; |
27 | const char *arg_name; |
28 | const QObject *arg_obj; |
29 | QDict *dict; |
30 | |
31 | dict = qobject_to(QDict, request); |
32 | if (!dict) { |
33 | error_setg(errp, "QMP input must be a JSON object" ); |
34 | return NULL; |
35 | } |
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 | || (!strcmp(arg_name, "exec-oob" ) && allow_oob)) { |
44 | if (qobject_type(arg_obj) != QTYPE_QSTRING) { |
45 | error_setg(errp, "QMP input member '%s' must be a string" , |
46 | arg_name); |
47 | return NULL; |
48 | } |
49 | if (exec_key) { |
50 | error_setg(errp, "QMP input member '%s' clashes with '%s'" , |
51 | arg_name, exec_key); |
52 | return NULL; |
53 | } |
54 | exec_key = arg_name; |
55 | } else if (!strcmp(arg_name, "arguments" )) { |
56 | if (qobject_type(arg_obj) != QTYPE_QDICT) { |
57 | error_setg(errp, |
58 | "QMP input member 'arguments' must be an object" ); |
59 | return NULL; |
60 | } |
61 | } else if (!strcmp(arg_name, "id" )) { |
62 | continue; |
63 | } else { |
64 | error_setg(errp, "QMP input member '%s' is unexpected" , |
65 | arg_name); |
66 | return NULL; |
67 | } |
68 | } |
69 | |
70 | if (!exec_key) { |
71 | error_setg(errp, "QMP input lacks member 'execute'" ); |
72 | return NULL; |
73 | } |
74 | |
75 | return dict; |
76 | } |
77 | |
78 | static QObject *do_qmp_dispatch(QmpCommandList *cmds, QObject *request, |
79 | bool allow_oob, Error **errp) |
80 | { |
81 | Error *local_err = NULL; |
82 | bool oob; |
83 | const char *command; |
84 | QDict *args, *dict; |
85 | QmpCommand *cmd; |
86 | QObject *ret = NULL; |
87 | |
88 | dict = qmp_dispatch_check_obj(request, allow_oob, errp); |
89 | if (!dict) { |
90 | return NULL; |
91 | } |
92 | |
93 | command = qdict_get_try_str(dict, "execute" ); |
94 | oob = false; |
95 | if (!command) { |
96 | assert(allow_oob); |
97 | command = qdict_get_str(dict, "exec-oob" ); |
98 | oob = true; |
99 | } |
100 | cmd = qmp_find_command(cmds, command); |
101 | if (cmd == NULL) { |
102 | error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND, |
103 | "The command %s has not been found" , command); |
104 | return NULL; |
105 | } |
106 | if (!cmd->enabled) { |
107 | error_setg(errp, "The command %s has been disabled for this instance" , |
108 | command); |
109 | return NULL; |
110 | } |
111 | if (oob && !(cmd->options & QCO_ALLOW_OOB)) { |
112 | error_setg(errp, "The command %s does not support OOB" , |
113 | command); |
114 | return NULL; |
115 | } |
116 | |
117 | if (runstate_check(RUN_STATE_PRECONFIG) && |
118 | !(cmd->options & QCO_ALLOW_PRECONFIG)) { |
119 | error_setg(errp, "The command '%s' isn't permitted in '%s' state" , |
120 | cmd->name, RunState_str(RUN_STATE_PRECONFIG)); |
121 | return NULL; |
122 | } |
123 | |
124 | if (!qdict_haskey(dict, "arguments" )) { |
125 | args = qdict_new(); |
126 | } else { |
127 | args = qdict_get_qdict(dict, "arguments" ); |
128 | qobject_ref(args); |
129 | } |
130 | |
131 | cmd->fn(args, &ret, &local_err); |
132 | if (local_err) { |
133 | error_propagate(errp, local_err); |
134 | } else if (cmd->options & QCO_NO_SUCCESS_RESP) { |
135 | g_assert(!ret); |
136 | } else if (!ret) { |
137 | /* TODO turn into assertion */ |
138 | ret = QOBJECT(qdict_new()); |
139 | } |
140 | |
141 | qobject_unref(args); |
142 | |
143 | return ret; |
144 | } |
145 | |
146 | QDict *qmp_error_response(Error *err) |
147 | { |
148 | QDict *rsp; |
149 | |
150 | rsp = qdict_from_jsonf_nofail("{ 'error': { 'class': %s, 'desc': %s } }" , |
151 | QapiErrorClass_str(error_get_class(err)), |
152 | error_get_pretty(err)); |
153 | error_free(err); |
154 | return rsp; |
155 | } |
156 | |
157 | /* |
158 | * Does @qdict look like a command to be run out-of-band? |
159 | */ |
160 | bool qmp_is_oob(const QDict *dict) |
161 | { |
162 | return qdict_haskey(dict, "exec-oob" ) |
163 | && !qdict_haskey(dict, "execute" ); |
164 | } |
165 | |
166 | QDict *qmp_dispatch(QmpCommandList *cmds, QObject *request, |
167 | bool allow_oob) |
168 | { |
169 | Error *err = NULL; |
170 | QDict *dict = qobject_to(QDict, request); |
171 | QObject *ret, *id = dict ? qdict_get(dict, "id" ) : NULL; |
172 | QDict *rsp; |
173 | |
174 | ret = do_qmp_dispatch(cmds, request, allow_oob, &err); |
175 | if (err) { |
176 | rsp = qmp_error_response(err); |
177 | } else if (ret) { |
178 | rsp = qdict_new(); |
179 | qdict_put_obj(rsp, "return" , ret); |
180 | } else { |
181 | /* Can only happen for commands with QCO_NO_SUCCESS_RESP */ |
182 | rsp = NULL; |
183 | } |
184 | |
185 | if (rsp && id) { |
186 | qdict_put_obj(rsp, "id" , qobject_ref(id)); |
187 | } |
188 | |
189 | return rsp; |
190 | } |
191 | |