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/json-parser.h" 18 #include "qapi/qmp/qdict.h" 19 #include "qapi/qmp/qjson.h" 20 #include "qapi/qmp/qbool.h" 21 #include "sysemu/sysemu.h" 22 23 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, "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 if (qobject_type(arg_obj) != QTYPE_QSTRING) { 44 error_setg(errp, 45 "QMP input member 'execute' must be a string"); 46 return NULL; 47 } 48 has_exec_key = true; 49 } else if (!strcmp(arg_name, "arguments")) { 50 if (qobject_type(arg_obj) != QTYPE_QDICT) { 51 error_setg(errp, 52 "QMP input member 'arguments' must be an object"); 53 return NULL; 54 } 55 } else if (!strcmp(arg_name, "id")) { 56 continue; 57 } else if (!strcmp(arg_name, "control")) { 58 if (qobject_type(arg_obj) != QTYPE_QDICT) { 59 error_setg(errp, 60 "QMP input member 'control' must be a dict"); 61 return NULL; 62 } 63 } else { 64 error_setg(errp, "QMP input member '%s' is unexpected", 65 arg_name); 66 return NULL; 67 } 68 } 69 70 if (!has_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 Error **errp) 80 { 81 Error *local_err = NULL; 82 const char *command; 83 QDict *args, *dict; 84 QmpCommand *cmd; 85 QObject *ret = NULL; 86 87 dict = qmp_dispatch_check_obj(request, errp); 88 if (!dict) { 89 return NULL; 90 } 91 92 command = qdict_get_str(dict, "execute"); 93 cmd = qmp_find_command(cmds, command); 94 if (cmd == NULL) { 95 error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND, 96 "The command %s has not been found", command); 97 return NULL; 98 } 99 if (!cmd->enabled) { 100 error_setg(errp, "The command %s has been disabled for this instance", 101 command); 102 return NULL; 103 } 104 105 if (runstate_check(RUN_STATE_PRECONFIG) && 106 !(cmd->options & QCO_ALLOW_PRECONFIG)) { 107 error_setg(errp, "The command '%s' isn't permitted in '%s' state", 108 cmd->name, RunState_str(RUN_STATE_PRECONFIG)); 109 return NULL; 110 } 111 112 if (!qdict_haskey(dict, "arguments")) { 113 args = qdict_new(); 114 } else { 115 args = qdict_get_qdict(dict, "arguments"); 116 qobject_ref(args); 117 } 118 119 cmd->fn(args, &ret, &local_err); 120 if (local_err) { 121 error_propagate(errp, local_err); 122 } else if (cmd->options & QCO_NO_SUCCESS_RESP) { 123 g_assert(!ret); 124 } else if (!ret) { 125 ret = QOBJECT(qdict_new()); 126 } 127 128 qobject_unref(args); 129 130 return ret; 131 } 132 133 QObject *qmp_build_error_object(Error *err) 134 { 135 return qobject_from_jsonf("{ 'class': %s, 'desc': %s }", 136 QapiErrorClass_str(error_get_class(err)), 137 error_get_pretty(err)); 138 } 139 140 /* 141 * Detect whether a request should be run out-of-band, by quickly 142 * peeking at whether we have: { "control": { "run-oob": true } }. By 143 * default commands are run in-band. 144 */ 145 bool qmp_is_oob(QDict *dict) 146 { 147 QBool *bool_obj; 148 149 dict = qdict_get_qdict(dict, "control"); 150 if (!dict) { 151 return false; 152 } 153 154 bool_obj = qobject_to(QBool, qdict_get(dict, "run-oob")); 155 if (!bool_obj) { 156 return false; 157 } 158 159 return qbool_get_bool(bool_obj); 160 } 161 162 QObject *qmp_dispatch(QmpCommandList *cmds, QObject *request) 163 { 164 Error *err = NULL; 165 QObject *ret; 166 QDict *rsp; 167 168 ret = do_qmp_dispatch(cmds, request, &err); 169 170 rsp = qdict_new(); 171 if (err) { 172 qdict_put_obj(rsp, "error", qmp_build_error_object(err)); 173 error_free(err); 174 } else if (ret) { 175 qdict_put_obj(rsp, "return", ret); 176 } else { 177 qobject_unref(rsp); 178 return NULL; 179 } 180 181 return QOBJECT(rsp); 182 } 183