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 22 QDict *qmp_dispatch_check_obj(const QObject *request, Error **errp) 23 { 24 const QDictEntry *ent; 25 const char *arg_name; 26 const QObject *arg_obj; 27 bool has_exec_key = false; 28 QDict *dict = NULL; 29 30 dict = qobject_to(QDict, request); 31 if (!dict) { 32 error_setg(errp, "QMP input must be a JSON object"); 33 return NULL; 34 } 35 36 for (ent = qdict_first(dict); ent; 37 ent = qdict_next(dict, ent)) { 38 arg_name = qdict_entry_key(ent); 39 arg_obj = qdict_entry_value(ent); 40 41 if (!strcmp(arg_name, "execute")) { 42 if (qobject_type(arg_obj) != QTYPE_QSTRING) { 43 error_setg(errp, 44 "QMP input member 'execute' must be a string"); 45 return NULL; 46 } 47 has_exec_key = true; 48 } else if (!strcmp(arg_name, "arguments")) { 49 if (qobject_type(arg_obj) != QTYPE_QDICT) { 50 error_setg(errp, 51 "QMP input member 'arguments' must be an object"); 52 return NULL; 53 } 54 } else if (!strcmp(arg_name, "id")) { 55 continue; 56 } else if (!strcmp(arg_name, "control")) { 57 if (qobject_type(arg_obj) != QTYPE_QDICT) { 58 error_setg(errp, 59 "QMP input member 'control' must be a dict"); 60 return NULL; 61 } 62 } else { 63 error_setg(errp, "QMP input member '%s' is unexpected", 64 arg_name); 65 return NULL; 66 } 67 } 68 69 if (!has_exec_key) { 70 error_setg(errp, "QMP input lacks member 'execute'"); 71 return NULL; 72 } 73 74 return dict; 75 } 76 77 static QObject *do_qmp_dispatch(QmpCommandList *cmds, QObject *request, 78 Error **errp) 79 { 80 Error *local_err = NULL; 81 const char *command; 82 QDict *args, *dict; 83 QmpCommand *cmd; 84 QObject *ret = NULL; 85 86 dict = qmp_dispatch_check_obj(request, errp); 87 if (!dict) { 88 return NULL; 89 } 90 91 command = qdict_get_str(dict, "execute"); 92 cmd = qmp_find_command(cmds, command); 93 if (cmd == NULL) { 94 error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND, 95 "The command %s has not been found", command); 96 return NULL; 97 } 98 if (!cmd->enabled) { 99 error_setg(errp, "The command %s has been disabled for this instance", 100 command); 101 return NULL; 102 } 103 104 if (!qdict_haskey(dict, "arguments")) { 105 args = qdict_new(); 106 } else { 107 args = qdict_get_qdict(dict, "arguments"); 108 QINCREF(args); 109 } 110 111 cmd->fn(args, &ret, &local_err); 112 if (local_err) { 113 error_propagate(errp, local_err); 114 } else if (cmd->options & QCO_NO_SUCCESS_RESP) { 115 g_assert(!ret); 116 } else if (!ret) { 117 ret = QOBJECT(qdict_new()); 118 } 119 120 QDECREF(args); 121 122 return ret; 123 } 124 125 QObject *qmp_build_error_object(Error *err) 126 { 127 return qobject_from_jsonf("{ 'class': %s, 'desc': %s }", 128 QapiErrorClass_str(error_get_class(err)), 129 error_get_pretty(err)); 130 } 131 132 /* 133 * Detect whether a request should be run out-of-band, by quickly 134 * peeking at whether we have: { "control": { "run-oob": true } }. By 135 * default commands are run in-band. 136 */ 137 bool qmp_is_oob(QDict *dict) 138 { 139 QBool *bool_obj; 140 141 dict = qdict_get_qdict(dict, "control"); 142 if (!dict) { 143 return false; 144 } 145 146 bool_obj = qobject_to(QBool, qdict_get(dict, "run-oob")); 147 if (!bool_obj) { 148 return false; 149 } 150 151 return qbool_get_bool(bool_obj); 152 } 153 154 QObject *qmp_dispatch(QmpCommandList *cmds, QObject *request) 155 { 156 Error *err = NULL; 157 QObject *ret; 158 QDict *rsp; 159 160 ret = do_qmp_dispatch(cmds, request, &err); 161 162 rsp = qdict_new(); 163 if (err) { 164 qdict_put_obj(rsp, "error", qmp_build_error_object(err)); 165 error_free(err); 166 } else if (ret) { 167 qdict_put_obj(rsp, "return", ret); 168 } else { 169 QDECREF(rsp); 170 return NULL; 171 } 172 173 return QOBJECT(rsp); 174 } 175