/*
 * admin_remote.c
 *
 * Copyright (C) 2015 Red Hat, Inc.
 *
 * 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: Erik Skultety <eskultet@redhat.com>
 */

#include <config.h>
#include <rpc/rpc.h>
#include "virtypedparam.h"
#include "admin_protocol.h"

typedef struct _remoteAdminPriv remoteAdminPriv;
typedef remoteAdminPriv *remoteAdminPrivPtr;

struct _remoteAdminPriv {
    virObjectLockable parent;

    int counter;
    virNetClientPtr client;
    virNetClientProgramPtr program;
};

static virClassPtr remoteAdminPrivClass;

static void
remoteAdminPrivDispose(void *opaque)
{
    remoteAdminPrivPtr priv = opaque;

    virObjectUnref(priv->program);
    virObjectUnref(priv->client);
}


/* Helpers */
static virAdmServerPtr
get_nonnull_server(virAdmConnectPtr conn, admin_nonnull_server server)
{
    return virAdmGetServer(conn, server.name);
}

static void
make_nonnull_server(admin_nonnull_server *srv_dst, virAdmServerPtr srv_src)
{
    srv_dst->name = srv_src->name;
}

static int
callFull(virAdmConnectPtr conn ATTRIBUTE_UNUSED,
         remoteAdminPrivPtr priv,
         int *fdin,
         size_t fdinlen,
         int **fdout,
         size_t *fdoutlen,
         int proc_nr,
         xdrproc_t args_filter, char *args,
         xdrproc_t ret_filter, char *ret)
{
    int rv;
    virNetClientProgramPtr prog = priv->program;
    int counter = priv->counter++;
    virNetClientPtr client = priv->client;

    /* Unlock, so that if we get any async events/stream data
     * while processing the RPC, we don't deadlock when our
     * callbacks for those are invoked
     */
    virObjectRef(priv);
    virObjectUnlock(priv);

    rv = virNetClientProgramCall(prog,
                                 client,
                                 counter,
                                 proc_nr,
                                 fdinlen, fdin,
                                 fdoutlen, fdout,
                                 args_filter, args,
                                 ret_filter, ret);

    virObjectLock(priv);
    virObjectUnref(priv);

    return rv;
}

static int
call(virAdmConnectPtr conn,
     unsigned int flags,
     int proc_nr,
     xdrproc_t args_filter, char *args,
     xdrproc_t ret_filter, char *ret)
{
    virCheckFlags(0, -1);

    return callFull(conn, conn->privateData,
                    NULL, 0, NULL, NULL, proc_nr,
                    args_filter, args, ret_filter, ret);
}

#include "admin_client.h"

static void
remoteAdminClientCloseFunc(virNetClientPtr client ATTRIBUTE_UNUSED,
                           int reason,
                           void *opaque)
{
    virAdmConnectCloseCallbackDataPtr cbdata = opaque;

    virObjectLock(cbdata);

    if (cbdata->callback) {
        VIR_DEBUG("Triggering connection close callback %p reason=%d, opaque=%p",
                  cbdata->callback, reason, cbdata->opaque);
        cbdata->callback(cbdata->conn, reason, cbdata->opaque);

        if (cbdata->freeCallback)
            cbdata->freeCallback(cbdata->opaque);
        cbdata->callback = NULL;
        cbdata->freeCallback = NULL;
    }
    virObjectUnlock(cbdata);
}

static int
remoteAdminConnectOpen(virAdmConnectPtr conn, unsigned int flags)
{
    int rv = -1;
    remoteAdminPrivPtr priv = conn->privateData;
    admin_connect_open_args args;

    virObjectLock(priv);

    args.flags = flags;

    if (virNetClientRegisterAsyncIO(priv->client) < 0) {
        VIR_DEBUG("Failed to add event watch, disabling events and support for"
                  " keepalive messages");
        virResetLastError();
    }

    virObjectRef(conn->closeCallback);
    virNetClientSetCloseCallback(priv->client, remoteAdminClientCloseFunc,
                                 conn->closeCallback,
                                 virObjectFreeCallback);

    if (call(conn, 0, ADMIN_PROC_CONNECT_OPEN,
             (xdrproc_t)xdr_admin_connect_open_args, (char *)&args,
             (xdrproc_t)xdr_void, (char *)NULL) == -1) {
        goto done;
    }

    rv = 0;

 done:
    virObjectUnlock(priv);
    return rv;
}

static int
remoteAdminConnectClose(virAdmConnectPtr conn)
{
    int rv = -1;
    remoteAdminPrivPtr priv = conn->privateData;

    virObjectLock(priv);

    if (call(conn, 0, ADMIN_PROC_CONNECT_CLOSE,
             (xdrproc_t)xdr_void, (char *)NULL,
             (xdrproc_t)xdr_void, (char *)NULL) == -1) {
        goto done;
    }

    virNetClientSetCloseCallback(priv->client, NULL, conn->closeCallback,
                                 virObjectFreeCallback);
    virNetClientClose(priv->client);

    rv = 0;

 done:
    virObjectUnlock(priv);
    return rv;
}

static void
remoteAdminPrivFree(void *opaque)
{
    virAdmConnectPtr conn = opaque;

    remoteAdminConnectClose(conn);
    virObjectUnref(conn->privateData);
}

static remoteAdminPrivPtr
remoteAdminPrivNew(const char *sock_path)
{
    remoteAdminPrivPtr priv = NULL;

    if (!(priv = virObjectLockableNew(remoteAdminPrivClass)))
        goto error;

    if (!(priv->client = virNetClientNewUNIX(sock_path, false, NULL)))
        goto error;

    if (!(priv->program = virNetClientProgramNew(ADMIN_PROGRAM,
                                                 ADMIN_PROTOCOL_VERSION,
                                                 NULL, 0, NULL)))
        goto error;

    if (virNetClientAddProgram(priv->client, priv->program) < 0)
        goto error;

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

static int
remoteAdminServerGetThreadPoolParameters(virAdmServerPtr srv,
                                         virTypedParameterPtr *params,
                                         int *nparams,
                                         unsigned int flags)
{
    int rv = -1;
    remoteAdminPrivPtr priv = srv->conn->privateData;
    admin_server_get_threadpool_parameters_args args;
    admin_server_get_threadpool_parameters_ret ret;

    args.flags = flags;
    make_nonnull_server(&args.srv, srv);

    memset(&ret, 0, sizeof(ret));
    virObjectLock(priv);

    if (call(srv->conn, 0, ADMIN_PROC_SERVER_GET_THREADPOOL_PARAMETERS,
             (xdrproc_t)xdr_admin_server_get_threadpool_parameters_args, (char *) &args,
             (xdrproc_t)xdr_admin_server_get_threadpool_parameters_ret, (char *) &ret) == -1)
        goto cleanup;

    if (virTypedParamsDeserialize((virTypedParameterRemotePtr) ret.params.params_val,
                                  ret.params.params_len,
                                  ADMIN_SERVER_THREADPOOL_PARAMETERS_MAX,
                                  params,
                                  nparams) < 0)
        goto cleanup;

    rv = 0;
    xdr_free((xdrproc_t)xdr_admin_server_get_threadpool_parameters_ret, (char *) &ret);

 cleanup:
    virObjectUnlock(priv);
    return rv;
}

static int
remoteAdminServerSetThreadPoolParameters(virAdmServerPtr srv,
                                         virTypedParameterPtr params,
                                         int nparams,
                                         unsigned int flags)
{
    int rv = -1;
    remoteAdminPrivPtr priv = srv->conn->privateData;
    admin_server_set_threadpool_parameters_args args;

    args.flags = flags;
    make_nonnull_server(&args.srv, srv);

    virObjectLock(priv);

    if (virTypedParamsSerialize(params, nparams,
                                (virTypedParameterRemotePtr *) &args.params.params_val,
                                &args.params.params_len,
                                0) < 0)
        goto cleanup;


    if (call(srv->conn, 0, ADMIN_PROC_SERVER_SET_THREADPOOL_PARAMETERS,
             (xdrproc_t)xdr_admin_server_set_threadpool_parameters_args, (char *) &args,
             (xdrproc_t)xdr_void, (char *) NULL) == -1)
        goto cleanup;

    rv = 0;
 cleanup:
    virTypedParamsRemoteFree((virTypedParameterRemotePtr) args.params.params_val,
                             args.params.params_len);
    virObjectUnlock(priv);
    return rv;
}