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 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 dict = qobject_to_qdict(request); 30 if (!dict) { 31 error_setg(errp, "QMP input must be a JSON object"); 32 return NULL; 33 } 34 35 for (ent = qdict_first(dict); ent; 36 ent = qdict_next(dict, ent)) { 37 arg_name = qdict_entry_key(ent); 38 arg_obj = qdict_entry_value(ent); 39 40 if (!strcmp(arg_name, "execute")) { 41 if (qobject_type(arg_obj) != QTYPE_QSTRING) { 42 error_setg(errp, 43 "QMP input member 'execute' must be a string"); 44 return NULL; 45 } 46 has_exec_key = true; 47 } else if (!strcmp(arg_name, "arguments")) { 48 if (qobject_type(arg_obj) != QTYPE_QDICT) { 49 error_setg(errp, 50 "QMP input member 'arguments' must be an object"); 51 return NULL; 52 } 53 } else { 54 error_setg(errp, "QMP input member '%s' is unexpected", 55 arg_name); 56 return NULL; 57 } 58 } 59 60 if (!has_exec_key) { 61 error_setg(errp, "QMP input lacks member 'execute'"); 62 return NULL; 63 } 64 65 return dict; 66 } 67 68 static QObject *do_qmp_dispatch(QmpCommandList *cmds, QObject *request, 69 Error **errp) 70 { 71 Error *local_err = NULL; 72 const char *command; 73 QDict *args, *dict; 74 QmpCommand *cmd; 75 QObject *ret = NULL; 76 77 dict = qmp_dispatch_check_obj(request, errp); 78 if (!dict) { 79 return NULL; 80 } 81 82 command = qdict_get_str(dict, "execute"); 83 cmd = qmp_find_command(cmds, command); 84 if (cmd == NULL) { 85 error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND, 86 "The command %s has not been found", command); 87 return NULL; 88 } 89 if (!cmd->enabled) { 90 error_setg(errp, "The command %s has been disabled for this instance", 91 command); 92 return NULL; 93 } 94 95 if (!qdict_haskey(dict, "arguments")) { 96 args = qdict_new(); 97 } else { 98 args = qdict_get_qdict(dict, "arguments"); 99 QINCREF(args); 100 } 101 102 cmd->fn(args, &ret, &local_err); 103 if (local_err) { 104 error_propagate(errp, local_err); 105 } else if (cmd->options & QCO_NO_SUCCESS_RESP) { 106 g_assert(!ret); 107 } else if (!ret) { 108 ret = QOBJECT(qdict_new()); 109 } 110 111 QDECREF(args); 112 113 return ret; 114 } 115 116 QObject *qmp_build_error_object(Error *err) 117 { 118 return qobject_from_jsonf("{ 'class': %s, 'desc': %s }", 119 QapiErrorClass_str(error_get_class(err)), 120 error_get_pretty(err)); 121 } 122 123 QObject *qmp_dispatch(QmpCommandList *cmds, QObject *request) 124 { 125 Error *err = NULL; 126 QObject *ret; 127 QDict *rsp; 128 129 ret = do_qmp_dispatch(cmds, request, &err); 130 131 rsp = qdict_new(); 132 if (err) { 133 qdict_put_obj(rsp, "error", qmp_build_error_object(err)); 134 error_free(err); 135 } else if (ret) { 136 qdict_put_obj(rsp, "return", ret); 137 } else { 138 QDECREF(rsp); 139 return NULL; 140 } 141 142 return QOBJECT(rsp); 143 } 144