qemu/qapi/qmp-dispatch.c

191 lines
5.1 KiB
C

/*
* Core Definitions for QAPI/QMP Dispatch
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qmp/dispatch.h"
#include "qapi/qmp/qdict.h"
#include "qapi/qmp/qjson.h"
#include "sysemu/runstate.h"
#include "qapi/qmp/qbool.h"
static QDict *qmp_dispatch_check_obj(const QObject *request, bool allow_oob,
Error **errp)
{
const char *exec_key = NULL;
const QDictEntry *ent;
const char *arg_name;
const QObject *arg_obj;
QDict *dict;
dict = qobject_to(QDict, request);
if (!dict) {
error_setg(errp, "QMP input must be a JSON object");
return NULL;
}
for (ent = qdict_first(dict); ent;
ent = qdict_next(dict, ent)) {
arg_name = qdict_entry_key(ent);
arg_obj = qdict_entry_value(ent);
if (!strcmp(arg_name, "execute")
|| (!strcmp(arg_name, "exec-oob") && allow_oob)) {
if (qobject_type(arg_obj) != QTYPE_QSTRING) {
error_setg(errp, "QMP input member '%s' must be a string",
arg_name);
return NULL;
}
if (exec_key) {
error_setg(errp, "QMP input member '%s' clashes with '%s'",
arg_name, exec_key);
return NULL;
}
exec_key = arg_name;
} else if (!strcmp(arg_name, "arguments")) {
if (qobject_type(arg_obj) != QTYPE_QDICT) {
error_setg(errp,
"QMP input member 'arguments' must be an object");
return NULL;
}
} else if (!strcmp(arg_name, "id")) {
continue;
} else {
error_setg(errp, "QMP input member '%s' is unexpected",
arg_name);
return NULL;
}
}
if (!exec_key) {
error_setg(errp, "QMP input lacks member 'execute'");
return NULL;
}
return dict;
}
static QObject *do_qmp_dispatch(QmpCommandList *cmds, QObject *request,
bool allow_oob, Error **errp)
{
Error *local_err = NULL;
bool oob;
const char *command;
QDict *args, *dict;
QmpCommand *cmd;
QObject *ret = NULL;
dict = qmp_dispatch_check_obj(request, allow_oob, errp);
if (!dict) {
return NULL;
}
command = qdict_get_try_str(dict, "execute");
oob = false;
if (!command) {
assert(allow_oob);
command = qdict_get_str(dict, "exec-oob");
oob = true;
}
cmd = qmp_find_command(cmds, command);
if (cmd == NULL) {
error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
"The command %s has not been found", command);
return NULL;
}
if (!cmd->enabled) {
error_setg(errp, "The command %s has been disabled for this instance",
command);
return NULL;
}
if (oob && !(cmd->options & QCO_ALLOW_OOB)) {
error_setg(errp, "The command %s does not support OOB",
command);
return NULL;
}
if (runstate_check(RUN_STATE_PRECONFIG) &&
!(cmd->options & QCO_ALLOW_PRECONFIG)) {
error_setg(errp, "The command '%s' isn't permitted in '%s' state",
cmd->name, RunState_str(RUN_STATE_PRECONFIG));
return NULL;
}
if (!qdict_haskey(dict, "arguments")) {
args = qdict_new();
} else {
args = qdict_get_qdict(dict, "arguments");
qobject_ref(args);
}
cmd->fn(args, &ret, &local_err);
if (local_err) {
error_propagate(errp, local_err);
} else if (cmd->options & QCO_NO_SUCCESS_RESP) {
g_assert(!ret);
} else if (!ret) {
/* TODO turn into assertion */
ret = QOBJECT(qdict_new());
}
qobject_unref(args);
return ret;
}
QDict *qmp_error_response(Error *err)
{
QDict *rsp;
rsp = qdict_from_jsonf_nofail("{ 'error': { 'class': %s, 'desc': %s } }",
QapiErrorClass_str(error_get_class(err)),
error_get_pretty(err));
error_free(err);
return rsp;
}
/*
* Does @qdict look like a command to be run out-of-band?
*/
bool qmp_is_oob(const QDict *dict)
{
return qdict_haskey(dict, "exec-oob")
&& !qdict_haskey(dict, "execute");
}
QDict *qmp_dispatch(QmpCommandList *cmds, QObject *request,
bool allow_oob)
{
Error *err = NULL;
QDict *dict = qobject_to(QDict, request);
QObject *ret, *id = dict ? qdict_get(dict, "id") : NULL;
QDict *rsp;
ret = do_qmp_dispatch(cmds, request, allow_oob, &err);
if (err) {
rsp = qmp_error_response(err);
} else if (ret) {
rsp = qdict_new();
qdict_put_obj(rsp, "return", ret);
} else {
/* Can only happen for commands with QCO_NO_SUCCESS_RESP */
rsp = NULL;
}
if (rsp && id) {
qdict_put_obj(rsp, "id", qobject_ref(id));
}
return rsp;
}