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, "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 { 56 error_setg(errp, "QMP input member '%s' is unexpected", 57 arg_name); 58 return NULL; 59 } 60 } 61 62 if (!has_exec_key) { 63 error_setg(errp, "QMP input lacks member 'execute'"); 64 return NULL; 65 } 66 67 return dict; 68 } 69 70 static QObject *do_qmp_dispatch(QmpCommandList *cmds, QObject *request, 71 Error **errp) 72 { 73 Error *local_err = NULL; 74 const char *command; 75 QDict *args, *dict; 76 QmpCommand *cmd; 77 QObject *ret = NULL; 78 79 dict = qmp_dispatch_check_obj(request, errp); 80 if (!dict) { 81 return NULL; 82 } 83 84 command = qdict_get_str(dict, "execute"); 85 cmd = qmp_find_command(cmds, command); 86 if (cmd == NULL) { 87 error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND, 88 "The command %s has not been found", command); 89 return NULL; 90 } 91 if (!cmd->enabled) { 92 error_setg(errp, "The command %s has been disabled for this instance", 93 command); 94 return NULL; 95 } 96 97 if (!qdict_haskey(dict, "arguments")) { 98 args = qdict_new(); 99 } else { 100 args = qdict_get_qdict(dict, "arguments"); 101 QINCREF(args); 102 } 103 104 cmd->fn(args, &ret, &local_err); 105 if (local_err) { 106 error_propagate(errp, local_err); 107 } else if (cmd->options & QCO_NO_SUCCESS_RESP) { 108 g_assert(!ret); 109 } else if (!ret) { 110 ret = QOBJECT(qdict_new()); 111 } 112 113 QDECREF(args); 114 115 return ret; 116 } 117 118 QObject *qmp_build_error_object(Error *err) 119 { 120 return qobject_from_jsonf("{ 'class': %s, 'desc': %s }", 121 QapiErrorClass_lookup[error_get_class(err)], 122 error_get_pretty(err)); 123 } 124 125 QObject *qmp_dispatch(QmpCommandList *cmds, QObject *request) 126 { 127 Error *err = NULL; 128 QObject *ret; 129 QDict *rsp; 130 131 ret = do_qmp_dispatch(cmds, request, &err); 132 133 rsp = qdict_new(); 134 if (err) { 135 qdict_put_obj(rsp, "error", qmp_build_error_object(err)); 136 error_free(err); 137 } else if (ret) { 138 qdict_put_obj(rsp, "return", ret); 139 } else { 140 QDECREF(rsp); 141 return NULL; 142 } 143 144 return QOBJECT(rsp); 145 } 146