qemu/monitor/qmp-cmds-control.c

/*
 * QMP commands related to the monitor (common to sysemu and tools)
 *
 * Copyright (c) 2003-2004 Fabrice Bellard
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "qemu/osdep.h"

#include "monitor-internal.h"
#include "qemu-version.h"
#include "qapi/compat-policy.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-control.h"
#include "qapi/qapi-commands-introspect.h"
#include "qapi/qapi-emit-events.h"
#include "qapi/qapi-introspect.h"
#include "qapi/qapi-visit-introspect.h"
#include "qapi/qobject-input-visitor.h"

/*
 * Accept QMP capabilities in @list for @mon.
 * On success, set mon->qmp.capab[], and return true.
 * On error, set @errp, and return false.
 */
static bool qmp_caps_accept(MonitorQMP *mon, QMPCapabilityList *list,
                            Error **errp)
{
    GString *unavailable = NULL;
    bool capab[QMP_CAPABILITY__MAX];

    memset(capab, 0, sizeof(capab));

    for (; list; list = list->next) {
        if (!mon->capab_offered[list->value]) {
            if (!unavailable) {
                unavailable = g_string_new(QMPCapability_str(list->value));
            } else {
                g_string_append_printf(unavailable, ", %s",
                                      QMPCapability_str(list->value));
            }
        }
        capab[list->value] = true;
    }

    if (unavailable) {
        error_setg(errp, "Capability %s not available", unavailable->str);
        g_string_free(unavailable, true);
        return false;
    }

    memcpy(mon->capab, capab, sizeof(capab));
    return true;
}

void qmp_qmp_capabilities(bool has_enable, QMPCapabilityList *enable,
                          Error **errp)
{
    Monitor *cur_mon = monitor_cur();
    MonitorQMP *mon;

    assert(monitor_is_qmp(cur_mon));
    mon = container_of(cur_mon, MonitorQMP, common);

    if (mon->commands == &qmp_commands) {
        error_set(errp, ERROR_CLASS_COMMAND_NOT_FOUND,
                  "Capabilities negotiation is already complete, command "
                  "ignored");
        return;
    }

    if (!qmp_caps_accept(mon, enable, errp)) {
        return;
    }

    mon->commands = &qmp_commands;
}

VersionInfo *qmp_query_version(Error **errp)
{
    VersionInfo *info = g_new0(VersionInfo, 1);

    info->qemu = g_new0(VersionTriple, 1);
    info->qemu->major = QEMU_VERSION_MAJOR;
    info->qemu->minor = QEMU_VERSION_MINOR;
    info->qemu->micro = QEMU_VERSION_MICRO;
    info->package = g_strdup(QEMU_PKGVERSION);

    return info;
}

static void query_commands_cb(const QmpCommand *cmd, void *opaque)
{
    CommandInfo *info;
    CommandInfoList **list = opaque;

    if (!cmd->enabled) {
        return;
    }

    info = g_malloc0(sizeof(*info));
    info->name = g_strdup(cmd->name);
    QAPI_LIST_PREPEND(*list, info);
}

CommandInfoList *qmp_query_commands(Error **errp)
{
    CommandInfoList *list = NULL;
    Monitor *cur_mon = monitor_cur();
    MonitorQMP *mon;

    assert(monitor_is_qmp(cur_mon));
    mon = container_of(cur_mon, MonitorQMP, common);

    qmp_for_each_command(mon->commands, query_commands_cb, &list);

    return list;
}

static void *split_off_generic_list(void *list,
                                    bool (*splitp)(void *elt),
                                    void **part)
{
    GenericList *keep = NULL, **keep_tailp = &keep;
    GenericList *split = NULL, **split_tailp = &split;
    GenericList *tail;

    for (tail = list; tail; tail = tail->next) {
        if (splitp(tail)) {
            *split_tailp = tail;
            split_tailp = &tail->next;
        } else {
            *keep_tailp = tail;
            keep_tailp = &tail->next;
        }
    }

    *keep_tailp = *split_tailp = NULL;
    *part = split;
    return keep;
}

static bool is_in(const char *s, strList *list)
{
    strList *tail;

    for (tail = list; tail; tail = tail->next) {
        if (!strcmp(tail->value, s)) {
            return true;
        }
    }
    return false;
}

static bool is_entity_deprecated(void *link)
{
    return is_in("deprecated", ((SchemaInfoList *)link)->value->features);
}

static bool is_member_deprecated(void *link)
{
    return is_in("deprecated",
                 ((SchemaInfoObjectMemberList *)link)->value->features);
}

static SchemaInfoList *zap_deprecated(SchemaInfoList *schema)
{
    void *to_zap;
    SchemaInfoList *tail;
    SchemaInfo *ent;

    schema = split_off_generic_list(schema, is_entity_deprecated, &to_zap);
    qapi_free_SchemaInfoList(to_zap);

    for (tail = schema; tail; tail = tail->next) {
        ent = tail->value;
        if (ent->meta_type == SCHEMA_META_TYPE_OBJECT) {
            ent->u.object.members
                = split_off_generic_list(ent->u.object.members,
                                         is_member_deprecated, &to_zap);
            qapi_free_SchemaInfoObjectMemberList(to_zap);
        }
    }

    return schema;
}

SchemaInfoList *qmp_query_qmp_schema(Error **errp)
{
    QObject *obj = qobject_from_qlit(&qmp_schema_qlit);
    Visitor *v = qobject_input_visitor_new(obj);
    SchemaInfoList *schema = NULL;

    /* test_visitor_in_qmp_introspect() ensures this can't fail */
    visit_type_SchemaInfoList(v, NULL, &schema, &error_abort);
    g_assert(schema);

    qobject_unref(obj);
    visit_free(v);

    if (compat_policy.deprecated_output == COMPAT_POLICY_OUTPUT_HIDE) {
        return zap_deprecated(schema);
    }
    return schema;
}