libvirt/src/rpc/virnetserver.c

/*
 * virnetserver.c: generic network RPC server
 *
 * Copyright (C) 2006-2015 Red Hat, Inc.
 * Copyright (C) 2006 Daniel P. Berrange
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * Author: Daniel P. Berrange <berrange@redhat.com>
 */

#include <config.h>

#include "virnetserver.h"
#include "virlog.h"
#include "viralloc.h"
#include "virerror.h"
#include "virthread.h"
#include "virthreadpool.h"
#include "virnetservermdns.h"
#include "virstring.h"

#define VIR_FROM_THIS VIR_FROM_RPC

VIR_LOG_INIT("rpc.netserver");


typedef struct _virNetServerJob virNetServerJob;
typedef virNetServerJob *virNetServerJobPtr;

struct _virNetServerJob {
    virNetServerClientPtr client;
    virNetMessagePtr msg;
    virNetServerProgramPtr prog;
};

struct _virNetServer {
    virObjectLockable parent;

    virThreadPoolPtr workers;

    char *mdnsGroupName;
    virNetServerMDNSPtr mdns;
    virNetServerMDNSGroupPtr mdnsGroup;

    size_t nservices;
    virNetServerServicePtr *services;

    size_t nprograms;
    virNetServerProgramPtr *programs;

    size_t nclients;                    /* Current clients count */
    virNetServerClientPtr *clients;     /* Clients */
    size_t nclients_max;                /* Max allowed clients count */
    size_t nclients_unauth;             /* Unauthenticated clients count */
    size_t nclients_unauth_max;         /* Max allowed unauth clients count */

    int keepaliveInterval;
    unsigned int keepaliveCount;

#ifdef WITH_GNUTLS
    virNetTLSContextPtr tls;
#endif

    virNetServerClientPrivNew clientPrivNew;
    virNetServerClientPrivPreExecRestart clientPrivPreExecRestart;
    virFreeCallback clientPrivFree;
    void *clientPrivOpaque;
};


static virClassPtr virNetServerClass;
static void virNetServerDispose(void *obj);
static void virNetServerUpdateServicesLocked(virNetServerPtr srv,
                                             bool enabled);
static inline size_t virNetServerTrackPendingAuthLocked(virNetServerPtr srv);
static inline size_t virNetServerTrackCompletedAuthLocked(virNetServerPtr srv);

static int virNetServerOnceInit(void)
{
    if (!(virNetServerClass = virClassNew(virClassForObjectLockable(),
                                          "virNetServer",
                                          sizeof(virNetServer),
                                          virNetServerDispose)))
        return -1;

    return 0;
}

VIR_ONCE_GLOBAL_INIT(virNetServer)


static int virNetServerProcessMsg(virNetServerPtr srv,
                                  virNetServerClientPtr client,
                                  virNetServerProgramPtr prog,
                                  virNetMessagePtr msg)
{
    int ret = -1;
    if (!prog) {
        /* Only send back an error for type == CALL. Other
         * message types are not expecting replies, so we
         * must just log it & drop them
         */
        if (msg->header.type == VIR_NET_CALL ||
            msg->header.type == VIR_NET_CALL_WITH_FDS) {
            if (virNetServerProgramUnknownError(client,
                                                msg,
                                                &msg->header) < 0)
                goto cleanup;
        } else {
            VIR_INFO("Dropping client mesage, unknown program %d version %d type %d proc %d",
                     msg->header.prog, msg->header.vers,
                     msg->header.type, msg->header.proc);
            /* Send a dummy reply to free up 'msg' & unblock client rx */
            virNetMessageClear(msg);
            msg->header.type = VIR_NET_REPLY;
            if (virNetServerClientSendMessage(client, msg) < 0)
                goto cleanup;
        }
        goto done;
    }

    if (virNetServerProgramDispatch(prog,
                                    srv,
                                    client,
                                    msg) < 0)
        goto cleanup;

 done:
    ret = 0;

 cleanup:
    return ret;
}

static void virNetServerHandleJob(void *jobOpaque, void *opaque)
{
    virNetServerPtr srv = opaque;
    virNetServerJobPtr job = jobOpaque;

    VIR_DEBUG("server=%p client=%p message=%p prog=%p",
              srv, job->client, job->msg, job->prog);

    if (virNetServerProcessMsg(srv, job->client, job->prog, job->msg) < 0)
        goto error;

    virObjectUnref(job->prog);
    virObjectUnref(job->client);
    VIR_FREE(job);
    return;

 error:
    virObjectUnref(job->prog);
    virNetMessageFree(job->msg);
    virNetServerClientClose(job->client);
    virObjectUnref(job->client);
    VIR_FREE(job);
}

static int virNetServerDispatchNewMessage(virNetServerClientPtr client,
                                          virNetMessagePtr msg,
                                          void *opaque)
{
    virNetServerPtr srv = opaque;
    virNetServerProgramPtr prog = NULL;
    unsigned int priority = 0;
    size_t i;
    int ret = -1;

    VIR_DEBUG("server=%p client=%p message=%p",
              srv, client, msg);

    virObjectLock(srv);
    for (i = 0; i < srv->nprograms; i++) {
        if (virNetServerProgramMatches(srv->programs[i], msg)) {
            prog = srv->programs[i];
            break;
        }
    }

    if (srv->workers) {
        virNetServerJobPtr job;

        if (VIR_ALLOC(job) < 0)
            goto cleanup;

        job->client = client;
        job->msg = msg;

        if (prog) {
            virObjectRef(prog);
            job->prog = prog;
            priority = virNetServerProgramGetPriority(prog, msg->header.proc);
        }

        ret = virThreadPoolSendJob(srv->workers, priority, job);

        if (ret < 0) {
            VIR_FREE(job);
            virObjectUnref(prog);
        }
    } else {
        ret = virNetServerProcessMsg(srv, client, prog, msg);
    }

 cleanup:
    virObjectUnlock(srv);

    return ret;
}


int virNetServerAddClient(virNetServerPtr srv,
                          virNetServerClientPtr client)
{
    virObjectLock(srv);

    if (srv->nclients >= srv->nclients_max) {
        virReportError(VIR_ERR_RPC,
                       _("Too many active clients (%zu), dropping connection from %s"),
                       srv->nclients_max, virNetServerClientRemoteAddrString(client));
        goto error;
    }

    if (virNetServerClientInit(client) < 0)
        goto error;

    if (VIR_EXPAND_N(srv->clients, srv->nclients, 1) < 0)
        goto error;
    srv->clients[srv->nclients-1] = client;
    virObjectRef(client);

    if (virNetServerClientNeedAuth(client))
        virNetServerTrackPendingAuthLocked(srv);

    if (srv->nclients_unauth_max &&
        srv->nclients_unauth == srv->nclients_unauth_max) {
        /* Temporarily stop accepting new clients */
        VIR_INFO("Temporarily suspending services "
                 "due to max_anonymous_clients");
        virNetServerUpdateServicesLocked(srv, false);
    }

    if (srv->nclients == srv->nclients_max) {
        /* Temporarily stop accepting new clients */
        VIR_INFO("Temporarily suspending services due to max_clients");
        virNetServerUpdateServicesLocked(srv, false);
    }

    virNetServerClientSetDispatcher(client,
                                    virNetServerDispatchNewMessage,
                                    srv);

    virNetServerClientInitKeepAlive(client, srv->keepaliveInterval,
                                    srv->keepaliveCount);

    virObjectUnlock(srv);
    return 0;

 error:
    virObjectUnlock(srv);
    return -1;
}

static int virNetServerDispatchNewClient(virNetServerServicePtr svc,
                                         virNetSocketPtr clientsock,
                                         void *opaque)
{
    virNetServerPtr srv = opaque;
    virNetServerClientPtr client;

    if (!(client = virNetServerClientNew(clientsock,
                                         virNetServerServiceGetAuth(svc),
                                         virNetServerServiceIsReadonly(svc),
                                         virNetServerServiceGetMaxRequests(svc),
#if WITH_GNUTLS
                                         virNetServerServiceGetTLSContext(svc),
#endif
                                         srv->clientPrivNew,
                                         srv->clientPrivPreExecRestart,
                                         srv->clientPrivFree,
                                         srv->clientPrivOpaque)))
        return -1;

    if (virNetServerAddClient(srv, client) < 0) {
        virNetServerClientClose(client);
        virObjectUnref(client);
        return -1;
    }
    virObjectUnref(client);
    return 0;
}


virNetServerPtr virNetServerNew(size_t min_workers,
                                size_t max_workers,
                                size_t priority_workers,
                                size_t max_clients,
                                size_t max_anonymous_clients,
                                int keepaliveInterval,
                                unsigned int keepaliveCount,
                                const char *mdnsGroupName,
                                virNetServerClientPrivNew clientPrivNew,
                                virNetServerClientPrivPreExecRestart clientPrivPreExecRestart,
                                virFreeCallback clientPrivFree,
                                void *clientPrivOpaque)
{
    virNetServerPtr srv;

    if (virNetServerInitialize() < 0)
        return NULL;

    if (!(srv = virObjectLockableNew(virNetServerClass)))
        return NULL;

    if (max_workers &&
        !(srv->workers = virThreadPoolNew(min_workers, max_workers,
                                          priority_workers,
                                          virNetServerHandleJob,
                                          srv)))
        goto error;

    srv->nclients_max = max_clients;
    srv->nclients_unauth_max = max_anonymous_clients;
    srv->keepaliveInterval = keepaliveInterval;
    srv->keepaliveCount = keepaliveCount;
    srv->clientPrivNew = clientPrivNew;
    srv->clientPrivPreExecRestart = clientPrivPreExecRestart;
    srv->clientPrivFree = clientPrivFree;
    srv->clientPrivOpaque = clientPrivOpaque;

    if (VIR_STRDUP(srv->mdnsGroupName, mdnsGroupName) < 0)
        goto error;
    if (srv->mdnsGroupName) {
        if (!(srv->mdns = virNetServerMDNSNew()))
            goto error;
        if (!(srv->mdnsGroup = virNetServerMDNSAddGroup(srv->mdns,
                                                        srv->mdnsGroupName)))
            goto error;
    }

    return srv;
 error:
    virObjectUnref(srv);
    return NULL;
}


virNetServerPtr virNetServerNewPostExecRestart(virJSONValuePtr object,
                                               virNetServerClientPrivNew clientPrivNew,
                                               virNetServerClientPrivNewPostExecRestart clientPrivNewPostExecRestart,
                                               virNetServerClientPrivPreExecRestart clientPrivPreExecRestart,
                                               virFreeCallback clientPrivFree,
                                               void *clientPrivOpaque)
{
    virNetServerPtr srv = NULL;
    virJSONValuePtr clients;
    virJSONValuePtr services;
    size_t i;
    ssize_t n;
    unsigned int min_workers;
    unsigned int max_workers;
    unsigned int priority_workers;
    unsigned int max_clients;
    unsigned int max_anonymous_clients;
    unsigned int keepaliveInterval;
    unsigned int keepaliveCount;
    const char *mdnsGroupName = NULL;

    if (virJSONValueObjectGetNumberUint(object, "min_workers", &min_workers) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing min_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectGetNumberUint(object, "max_workers", &max_workers) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing max_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectGetNumberUint(object, "priority_workers", &priority_workers) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing priority_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectGetNumberUint(object, "max_clients", &max_clients) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing max_clients data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectHasKey(object, "max_anonymous_clients")) {
        if (virJSONValueObjectGetNumberUint(object, "max_anonymous_clients",
                                            &max_anonymous_clients) < 0) {
            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                           _("Malformed max_anonymous_clients data in JSON document"));
            goto error;
        }
    } else {
        max_anonymous_clients = max_clients;
    }
    if (virJSONValueObjectGetNumberUint(object, "keepaliveInterval", &keepaliveInterval) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing keepaliveInterval data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectGetNumberUint(object, "keepaliveCount", &keepaliveCount) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing keepaliveCount data in JSON document"));
        goto error;
    }

    if (virJSONValueObjectHasKey(object, "mdnsGroupName") &&
        (!(mdnsGroupName = virJSONValueObjectGetString(object, "mdnsGroupName")))) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Malformed mdnsGroupName data in JSON document"));
        goto error;
    }

    if (!(srv = virNetServerNew(min_workers, max_workers,
                                priority_workers, max_clients,
                                max_anonymous_clients,
                                keepaliveInterval, keepaliveCount,
                                mdnsGroupName,
                                clientPrivNew, clientPrivPreExecRestart,
                                clientPrivFree, clientPrivOpaque)))
        goto error;

    if (!(services = virJSONValueObjectGet(object, "services"))) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing services data in JSON document"));
        goto error;
    }

    n =  virJSONValueArraySize(services);
    if (n < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Malformed services data in JSON document"));
        goto error;
    }

    for (i = 0; i < n; i++) {
        virNetServerServicePtr service;
        virJSONValuePtr child = virJSONValueArrayGet(services, i);
        if (!child) {
            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                           _("Missing service data in JSON document"));
            goto error;
        }

        if (!(service = virNetServerServiceNewPostExecRestart(child)))
            goto error;

        /* XXX mdns entry names ? */
        if (virNetServerAddService(srv, service, NULL) < 0) {
            virObjectUnref(service);
            goto error;
        }
    }


    if (!(clients = virJSONValueObjectGet(object, "clients"))) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Missing clients data in JSON document"));
        goto error;
    }

    n =  virJSONValueArraySize(clients);
    if (n < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Malformed clients data in JSON document"));
        goto error;
    }

    for (i = 0; i < n; i++) {
        virNetServerClientPtr client;
        virJSONValuePtr child = virJSONValueArrayGet(clients, i);
        if (!child) {
            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                           _("Missing client data in JSON document"));
            goto error;
        }

        if (!(client = virNetServerClientNewPostExecRestart(child,
                                                            clientPrivNewPostExecRestart,
                                                            clientPrivPreExecRestart,
                                                            clientPrivFree,
                                                            clientPrivOpaque)))
            goto error;

        if (virNetServerAddClient(srv, client) < 0) {
            virObjectUnref(client);
            goto error;
        }
        virObjectUnref(client);
    }

    return srv;

 error:
    virObjectUnref(srv);
    return NULL;
}


virJSONValuePtr virNetServerPreExecRestart(virNetServerPtr srv)
{
    virJSONValuePtr object;
    virJSONValuePtr clients;
    virJSONValuePtr services;
    size_t i;

    virObjectLock(srv);

    if (!(object = virJSONValueNewObject()))
        goto error;

    if (virJSONValueObjectAppendNumberUint(object, "min_workers",
                                           virThreadPoolGetMinWorkers(srv->workers)) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set min_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "max_workers",
                                           virThreadPoolGetMaxWorkers(srv->workers)) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set max_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "priority_workers",
                                           virThreadPoolGetPriorityWorkers(srv->workers)) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set priority_workers data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "max_clients", srv->nclients_max) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set max_clients data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "max_anonymous_clients",
                                           srv->nclients_unauth_max) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set max_anonymous_clients data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "keepaliveInterval", srv->keepaliveInterval) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set keepaliveInterval data in JSON document"));
        goto error;
    }
    if (virJSONValueObjectAppendNumberUint(object, "keepaliveCount", srv->keepaliveCount) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set keepaliveCount data in JSON document"));
        goto error;
    }

    if (srv->mdnsGroupName &&
        virJSONValueObjectAppendString(object, "mdnsGroupName", srv->mdnsGroupName) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Cannot set mdnsGroupName data in JSON document"));
        goto error;
    }

    services = virJSONValueNewArray();
    if (virJSONValueObjectAppend(object, "services", services) < 0) {
        virJSONValueFree(services);
        goto error;
    }

    for (i = 0; i < srv->nservices; i++) {
        virJSONValuePtr child;
        if (!(child = virNetServerServicePreExecRestart(srv->services[i])))
            goto error;

        if (virJSONValueArrayAppend(services, child) < 0) {
            virJSONValueFree(child);
            goto error;
        }
    }

    clients = virJSONValueNewArray();
    if (virJSONValueObjectAppend(object, "clients", clients) < 0) {
        virJSONValueFree(clients);
        goto error;
    }

    for (i = 0; i < srv->nclients; i++) {
        virJSONValuePtr child;
        if (!(child = virNetServerClientPreExecRestart(srv->clients[i])))
            goto error;

        if (virJSONValueArrayAppend(clients, child) < 0) {
            virJSONValueFree(child);
            goto error;
        }
    }

    virObjectUnlock(srv);

    return object;

 error:
    virJSONValueFree(object);
    virObjectUnlock(srv);
    return NULL;
}



int virNetServerAddService(virNetServerPtr srv,
                           virNetServerServicePtr svc,
                           const char *mdnsEntryName)
{
    virObjectLock(srv);

    if (VIR_EXPAND_N(srv->services, srv->nservices, 1) < 0)
        goto error;

    if (mdnsEntryName) {
        int port = virNetServerServiceGetPort(svc);

        if (!virNetServerMDNSAddEntry(srv->mdnsGroup,
                                      mdnsEntryName,
                                      port)) {
            srv->nservices--;
            goto error;
        }
    }

    srv->services[srv->nservices-1] = svc;
    virObjectRef(svc);

    virNetServerServiceSetDispatcher(svc,
                                     virNetServerDispatchNewClient,
                                     srv);

    virObjectUnlock(srv);
    return 0;

 error:
    virObjectUnlock(srv);
    return -1;
}

int virNetServerAddProgram(virNetServerPtr srv,
                           virNetServerProgramPtr prog)
{
    virObjectLock(srv);

    if (VIR_EXPAND_N(srv->programs, srv->nprograms, 1) < 0)
        goto error;

    srv->programs[srv->nprograms-1] = virObjectRef(prog);

    virObjectUnlock(srv);
    return 0;

 error:
    virObjectUnlock(srv);
    return -1;
}

#if WITH_GNUTLS
int virNetServerSetTLSContext(virNetServerPtr srv,
                              virNetTLSContextPtr tls)
{
    srv->tls = virObjectRef(tls);
    return 0;
}
#endif


static void
virNetServerUpdateServicesLocked(virNetServerPtr srv,
                                 bool enabled)
{
    size_t i;

    for (i = 0; i < srv->nservices; i++)
        virNetServerServiceToggle(srv->services[i], enabled);
}


void virNetServerUpdateServices(virNetServerPtr srv,
                                bool enabled)
{
    virObjectLock(srv);
    virNetServerUpdateServicesLocked(srv, enabled);
    virObjectUnlock(srv);
}

/**
 * virNetServerCheckLimits:
 * @srv: server to check limits on
 *
 * Check if limits like max_clients or max_anonymous_clients
 * are satisfied and if so, re-enable accepting new clients.
 * The @srv must be locked when this function is called.
 */
static void
virNetServerCheckLimits(virNetServerPtr srv)
{
    /* Enable services if we can accept a new client.
     * The new client can be accepted if both max_clients and
     * max_anonymous_clients wouldn't get overcommitted by
     * accepting it. */
    VIR_DEBUG("Considering re-enabling services: "
              "nclients=%zu nclients_max=%zu "
              "nclients_unauth=%zu nclients_unauth_max=%zu",
              srv->nclients, srv->nclients_max,
              srv->nclients_unauth, srv->nclients_unauth_max);
    if (srv->nclients < srv->nclients_max &&
        (!srv->nclients_unauth_max ||
         srv->nclients_unauth < srv->nclients_unauth_max)) {
        /* Now it makes sense to accept() a new client. */
        VIR_INFO("Re-enabling services");
        virNetServerUpdateServicesLocked(srv, true);
    }
}

void virNetServerDispose(void *obj)
{
    virNetServerPtr srv = obj;
    size_t i;

    for (i = 0; i < srv->nservices; i++)
        virNetServerServiceToggle(srv->services[i], false);

    virThreadPoolFree(srv->workers);

    for (i = 0; i < srv->nservices; i++)
        virObjectUnref(srv->services[i]);
    VIR_FREE(srv->services);

    for (i = 0; i < srv->nprograms; i++)
        virObjectUnref(srv->programs[i]);
    VIR_FREE(srv->programs);

    for (i = 0; i < srv->nclients; i++) {
        virNetServerClientClose(srv->clients[i]);
        virObjectUnref(srv->clients[i]);
    }
    VIR_FREE(srv->clients);

    VIR_FREE(srv->mdnsGroupName);
    virNetServerMDNSFree(srv->mdns);
}

void virNetServerClose(virNetServerPtr srv)
{
    size_t i;

    if (!srv)
        return;

    virObjectLock(srv);

    for (i = 0; i < srv->nservices; i++)
        virNetServerServiceClose(srv->services[i]);

    virObjectUnlock(srv);
}

static inline size_t
virNetServerTrackPendingAuthLocked(virNetServerPtr srv)
{
    return ++srv->nclients_unauth;
}

static inline size_t
virNetServerTrackCompletedAuthLocked(virNetServerPtr srv)
{
    return --srv->nclients_unauth;
}

size_t virNetServerTrackPendingAuth(virNetServerPtr srv)
{
    size_t ret;
    virObjectLock(srv);
    ret = virNetServerTrackPendingAuthLocked(srv);
    virObjectUnlock(srv);
    return ret;
}

size_t virNetServerTrackCompletedAuth(virNetServerPtr srv)
{
    size_t ret;
    virObjectLock(srv);
    ret = virNetServerTrackCompletedAuthLocked(srv);
    virNetServerCheckLimits(srv);
    virObjectUnlock(srv);
    return ret;
}

bool
virNetServerHasClients(virNetServerPtr srv)
{
    bool ret;

    virObjectLock(srv);
    ret = !!srv->nclients;
    virObjectUnlock(srv);

    return ret;
}

void
virNetServerProcessClients(virNetServerPtr srv)
{
    size_t i;

    virObjectLock(srv);

 reprocess:
    for (i = 0; i < srv->nclients; i++) {
        /* Coverity 5.3.0 couldn't see that srv->clients is non-NULL
         * if srv->nclients is non-zero.  */
        sa_assert(srv->clients);
        if (virNetServerClientWantClose(srv->clients[i]))
            virNetServerClientClose(srv->clients[i]);
        if (virNetServerClientIsClosed(srv->clients[i])) {
            virNetServerClientPtr client = srv->clients[i];

            VIR_DELETE_ELEMENT(srv->clients, i, srv->nclients);

            if (virNetServerClientNeedAuth(client))
                virNetServerTrackCompletedAuthLocked(srv);

            virNetServerCheckLimits(srv);

            virObjectUnlock(srv);
            virObjectUnref(client);
            virObjectLock(srv);

            goto reprocess;
        }
    }

    virObjectUnlock(srv);
}

int
virNetServerStart(virNetServerPtr srv)
{
    /*
     * Do whatever needs to be done before starting.
     */
    if (!srv->mdns)
        return 0;

    return virNetServerMDNSStart(srv->mdns);
}