virdbus.c 51.9 KB
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/*
 * virdbus.c: helper for using DBus
 *
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 * Copyright (C) 2012-2014 Red Hat, Inc.
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 *
 * 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
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 * License along with this library.  If not, see
O
Osier Yang 已提交
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 * <http://www.gnu.org/licenses/>.
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 *
 */

#include <config.h>

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#include "virdbuspriv.h"
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#include "viralloc.h"
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#include "virerror.h"
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#include "virlog.h"
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#include "virthread.h"
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#include "virstring.h"
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#define VIR_FROM_THIS VIR_FROM_DBUS

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VIR_LOG_INIT("util.dbus");

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#ifdef WITH_DBUS
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static bool sharedBus = true;
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static DBusConnection *systembus = NULL;
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static DBusConnection *sessionbus = NULL;
static virOnceControl systemonce = VIR_ONCE_CONTROL_INITIALIZER;
static virOnceControl sessiononce = VIR_ONCE_CONTROL_INITIALIZER;
static DBusError systemdbuserr;
static DBusError sessiondbuserr;
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static dbus_bool_t virDBusAddWatch(DBusWatch *watch, void *data);
static void virDBusRemoveWatch(DBusWatch *watch, void *data);
static void virDBusToggleWatch(DBusWatch *watch, void *data);

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void virDBusSetSharedBus(bool shared)
{
    sharedBus = shared;
}

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static DBusConnection *virDBusBusInit(DBusBusType type, DBusError *dbuserr)
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{
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    DBusConnection *bus;

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    /* Allocate and initialize a new HAL context */
    dbus_connection_set_change_sigpipe(FALSE);
    dbus_threads_init_default();

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    dbus_error_init(dbuserr);
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    bus = sharedBus ?
        dbus_bus_get(type, dbuserr) :
        dbus_bus_get_private(type, dbuserr);
    if (!bus)
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        return NULL;
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    dbus_connection_set_exit_on_disconnect(bus, FALSE);
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    /* Register dbus watch callbacks */
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    if (!dbus_connection_set_watch_functions(bus,
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                                             virDBusAddWatch,
                                             virDBusRemoveWatch,
                                             virDBusToggleWatch,
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                                             bus, NULL)) {
        return NULL;
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    }
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    return bus;
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}

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static void virDBusSystemBusInit(void)
{
    systembus = virDBusBusInit(DBUS_BUS_SYSTEM, &systemdbuserr);
}
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static DBusConnection *
virDBusGetSystemBusInternal(void)
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{
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    if (virOnce(&systemonce, virDBusSystemBusInit) < 0) {
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        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Unable to run one time DBus initializer"));
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        return NULL;
    }

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    return systembus;
}


DBusConnection *
virDBusGetSystemBus(void)
{
    DBusConnection *bus;

    if (!(bus = virDBusGetSystemBusInternal())) {
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        virReportError(VIR_ERR_INTERNAL_ERROR,
                       _("Unable to get DBus system bus connection: %s"),
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                       systemdbuserr.message ? systemdbuserr.message : "watch setup failed");
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        return NULL;
    }

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    return bus;
}


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/**
 * virDBusHasSystemBus:
 *
 * Check if dbus system bus is running. This does not
 * imply that we have a connection. DBus might be running
 * and refusing connections due to its client limit. The
 * latter must be treated as a fatal error.
 *
 * Return false if dbus is not available, true if probably available.
 */
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bool
virDBusHasSystemBus(void)
{
    if (virDBusGetSystemBusInternal())
        return true;

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    if (systemdbuserr.name &&
        (STREQ(systemdbuserr.name, "org.freedesktop.DBus.Error.FileNotFound") ||
         STREQ(systemdbuserr.name, "org.freedesktop.DBus.Error.NoServer"))) {
        VIR_DEBUG("System DBus not available: %s", NULLSTR(systemdbuserr.message));
        return false;
    }
    return true;
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}


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void virDBusCloseSystemBus(void)
{
    if (systembus && !sharedBus) {
        dbus_connection_close(systembus);
        systembus = NULL;
    }
}

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static void virDBusSessionBusInit(void)
{
    sessionbus = virDBusBusInit(DBUS_BUS_SESSION, &sessiondbuserr);
}

DBusConnection *virDBusGetSessionBus(void)
{
    if (virOnce(&sessiononce, virDBusSessionBusInit) < 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Unable to run one time DBus initializer"));
        return NULL;
    }

    if (!sessionbus) {
        virReportError(VIR_ERR_INTERNAL_ERROR,
                       _("Unable to get DBus session bus connection: %s"),
                       sessiondbuserr.message ? sessiondbuserr.message : "watch setup failed");
        return NULL;
    }

    return sessionbus;
}

struct virDBusWatch
{
    int watch;
    DBusConnection *bus;
};

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static void virDBusWatchCallback(int fdatch ATTRIBUTE_UNUSED,
                                 int fd ATTRIBUTE_UNUSED,
                                 int events, void *opaque)
{
    DBusWatch *watch = opaque;
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    struct virDBusWatch *info;
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    int dbus_flags = 0;

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    info = dbus_watch_get_data(watch);

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    if (events & VIR_EVENT_HANDLE_READABLE)
        dbus_flags |= DBUS_WATCH_READABLE;
    if (events & VIR_EVENT_HANDLE_WRITABLE)
        dbus_flags |= DBUS_WATCH_WRITABLE;
    if (events & VIR_EVENT_HANDLE_ERROR)
        dbus_flags |= DBUS_WATCH_ERROR;
    if (events & VIR_EVENT_HANDLE_HANGUP)
        dbus_flags |= DBUS_WATCH_HANGUP;

    (void)dbus_watch_handle(watch, dbus_flags);

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    while (dbus_connection_dispatch(info->bus) == DBUS_DISPATCH_DATA_REMAINS)
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        /* keep dispatching while data remains */;
}


static int virDBusTranslateWatchFlags(int dbus_flags)
{
    unsigned int flags = 0;
    if (dbus_flags & DBUS_WATCH_READABLE)
        flags |= VIR_EVENT_HANDLE_READABLE;
    if (dbus_flags & DBUS_WATCH_WRITABLE)
        flags |= VIR_EVENT_HANDLE_WRITABLE;
    if (dbus_flags & DBUS_WATCH_ERROR)
        flags |= VIR_EVENT_HANDLE_ERROR;
    if (dbus_flags & DBUS_WATCH_HANGUP)
        flags |= VIR_EVENT_HANDLE_HANGUP;
    return flags;
}


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static void virDBusWatchFree(void *data)
{
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    struct virDBusWatch *info = data;
    VIR_FREE(info);
}

static dbus_bool_t virDBusAddWatch(DBusWatch *watch,
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                                   void *data)
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{
    int flags = 0;
    int fd;
    struct virDBusWatch *info;

    if (VIR_ALLOC(info) < 0)
        return 0;

    if (dbus_watch_get_enabled(watch))
        flags = virDBusTranslateWatchFlags(dbus_watch_get_flags(watch));

# if HAVE_DBUS_WATCH_GET_UNIX_FD
    fd = dbus_watch_get_unix_fd(watch);
# else
    fd = dbus_watch_get_fd(watch);
# endif
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    dbus_watch_set_data(watch, info, virDBusWatchFree);
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    info->bus = (DBusConnection *)data;
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    info->watch = virEventAddHandle(fd, flags,
                                    virDBusWatchCallback,
                                    watch, NULL);
    if (info->watch < 0) {
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        dbus_watch_set_data(watch, NULL, NULL);
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        return 0;
    }

    return 1;
}


static void virDBusRemoveWatch(DBusWatch *watch,
                               void *data ATTRIBUTE_UNUSED)
{
    struct virDBusWatch *info;

    info = dbus_watch_get_data(watch);

    (void)virEventRemoveHandle(info->watch);
}


static void virDBusToggleWatch(DBusWatch *watch,
                               void *data ATTRIBUTE_UNUSED)
{
    int flags = 0;
    struct virDBusWatch *info;

    if (dbus_watch_get_enabled(watch))
        flags = virDBusTranslateWatchFlags(dbus_watch_get_flags(watch));

    info = dbus_watch_get_data(watch);

    (void)virEventUpdateHandle(info->watch, flags);
}

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# define VIR_DBUS_TYPE_STACK_MAX_DEPTH 32

static const char virDBusBasicTypes[] = {
    DBUS_TYPE_BYTE,
    DBUS_TYPE_BOOLEAN,
    DBUS_TYPE_INT16,
    DBUS_TYPE_UINT16,
    DBUS_TYPE_INT32,
    DBUS_TYPE_UINT32,
    DBUS_TYPE_INT64,
    DBUS_TYPE_UINT64,
    DBUS_TYPE_DOUBLE,
    DBUS_TYPE_STRING,
    DBUS_TYPE_OBJECT_PATH,
    DBUS_TYPE_SIGNATURE,
};

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static bool virDBusIsBasicType(char c)
{
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    return !!memchr(virDBusBasicTypes, c, ARRAY_CARDINALITY(virDBusBasicTypes));
}

/*
 * All code related to virDBusMessageIterEncode and
 * virDBusMessageIterDecode is derived from systemd
 * bus_message_append_ap()/message_read_ap() in
 * bus-message.c under the terms of the LGPLv2+
 */
static int
virDBusSignatureLengthInternal(const char *s,
                               bool allowDict,
                               unsigned arrayDepth,
                               unsigned structDepth,
                               size_t *l)
{
    if (virDBusIsBasicType(*s) || *s == DBUS_TYPE_VARIANT) {
        *l = 1;
        return 0;
    }

    if (*s == DBUS_TYPE_ARRAY) {
        size_t t;

        if (arrayDepth >= VIR_DBUS_TYPE_STACK_MAX_DEPTH) {
            virReportError(VIR_ERR_INTERNAL_ERROR,
                           _("Signature '%s' too deeply nested"),
                           s);
            return -1;
        }

        if (virDBusSignatureLengthInternal(s + 1,
                                           true,
                                           arrayDepth + 1,
                                           structDepth,
                                           &t) < 0)
            return -1;

        *l = t + 1;
        return 0;
    }

    if (*s == DBUS_STRUCT_BEGIN_CHAR) {
        const char *p = s + 1;

        if (structDepth >= VIR_DBUS_TYPE_STACK_MAX_DEPTH) {
            virReportError(VIR_ERR_INTERNAL_ERROR,
                           _("Signature '%s' too deeply nested"),
                           s);
            return -1;
        }

        while (*p != DBUS_STRUCT_END_CHAR) {
            size_t t;

            if (virDBusSignatureLengthInternal(p,
                                               false,
                                               arrayDepth,
                                               structDepth + 1,
                                               &t) < 0)
                return -1;

            p += t;
        }

        *l = p - s + 1;
        return 0;
    }

    if (*s == DBUS_DICT_ENTRY_BEGIN_CHAR && allowDict) {
        const char *p = s + 1;
        unsigned n = 0;
        if (structDepth >= VIR_DBUS_TYPE_STACK_MAX_DEPTH) {
            virReportError(VIR_ERR_INTERNAL_ERROR,
                           _("Signature '%s' too deeply nested"),
                           s);
            return -1;
        }

        while (*p != DBUS_DICT_ENTRY_END_CHAR) {
            size_t t;

            if (n == 0 && !virDBusIsBasicType(*p)) {
                virReportError(VIR_ERR_INTERNAL_ERROR,
                               _("Dict entry in signature '%s' must be a basic type"),
                               s);
                return -1;
            }

            if (virDBusSignatureLengthInternal(p,
                                               false,
                                               arrayDepth,
                                               structDepth + 1,
                                               &t) < 0)
                return -1;

            p += t;
            n++;
        }

        if (n != 2) {
            virReportError(VIR_ERR_INTERNAL_ERROR,
                           _("Dict entry in signature '%s' is wrong size"),
                           s);
            return -1;
        }

        *l = p - s + 1;
        return 0;
    }

    virReportError(VIR_ERR_INTERNAL_ERROR,
                   _("Unexpected signature '%s'"), s);
    return -1;
}


static int virDBusSignatureLength(const char *s, size_t *l)
{
    return virDBusSignatureLengthInternal(s, true, 0, 0, l);
}



/* Ideally, we'd just call ourselves recursively on every
 * complex type. However, the state of a va_list that is
 * passed to a function is undefined after that function
 * returns. This means we need to decode the va_list linearly
 * in a single stackframe. We hence implement our own
 * home-grown stack in an array. */

typedef struct _virDBusTypeStack virDBusTypeStack;
struct _virDBusTypeStack {
    const char *types;
    size_t nstruct;
    size_t narray;
    DBusMessageIter *iter;
};

static int virDBusTypeStackPush(virDBusTypeStack **stack,
                                size_t *nstack,
                                DBusMessageIter *iter,
                                const char *types,
                                size_t nstruct,
                                size_t narray)
{
    if (*nstack >= VIR_DBUS_TYPE_STACK_MAX_DEPTH) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("DBus type too deeply nested"));
        return -1;
    }

    if (VIR_EXPAND_N(*stack, *nstack, 1) < 0)
        return -1;

    (*stack)[(*nstack) - 1].iter = iter;
    (*stack)[(*nstack) - 1].types = types;
    (*stack)[(*nstack) - 1].nstruct = nstruct;
    (*stack)[(*nstack) - 1].narray = narray;
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    VIR_DEBUG("Pushed types='%s' nstruct=%zu narray=%zu", types, nstruct, narray);
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    return 0;
}


static int virDBusTypeStackPop(virDBusTypeStack **stack,
                               size_t *nstack,
                               DBusMessageIter **iter,
                               const char **types,
                               size_t *nstruct,
                               size_t *narray)
{
    if (*nstack == 0) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("DBus type stack is empty"));
        return -1;
    }

    *iter = (*stack)[(*nstack) - 1].iter;
    *types = (*stack)[(*nstack) - 1].types;
    *nstruct = (*stack)[(*nstack) - 1].nstruct;
    *narray = (*stack)[(*nstack) - 1].narray;
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    VIR_DEBUG("Popped types='%s' nstruct=%zu narray=%zu", *types, *nstruct, *narray);
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    VIR_SHRINK_N(*stack, *nstack, 1);

    return 0;
}


static void virDBusTypeStackFree(virDBusTypeStack **stack,
                                 size_t *nstack)
{
    size_t i;
    /* The iter in the first level of the stack is the
     * root iter which must not be freed
     */
    for (i = 1; i < *nstack; i++) {
        VIR_FREE((*stack)[i].iter);
    }
    VIR_FREE(*stack);
}


# define SET_NEXT_VAL(dbustype, vargtype, sigtype, fmt)                 \
    do {                                                                \
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        dbustype x;                                                     \
        if (arrayref) {                                                 \
            vargtype *valarray = arrayptr;                              \
            x = (dbustype)*valarray;                                    \
            valarray++;                                                 \
            arrayptr = valarray;                                        \
        } else {                                                        \
            x = (dbustype)va_arg(args, vargtype);                       \
        }                                                               \
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        if (!dbus_message_iter_append_basic(iter, sigtype, &x)) {       \
            virReportError(VIR_ERR_INTERNAL_ERROR,                      \
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                           _("Cannot append basic type %s"), #vargtype);\
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            goto cleanup;                                               \
        }                                                               \
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        VIR_DEBUG("Appended basic type '" #dbustype "' varg '" #vargtype\
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                  "' sig '%c' val '" fmt "'", sigtype, (vargtype)x);    \
    } while (0)

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static int
virDBusMessageIterEncode(DBusMessageIter *rootiter,
                         const char *types,
                         va_list args)
{
    int ret = -1;
    size_t narray;
    size_t nstruct;
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    bool arrayref = false;
    void *arrayptr = NULL;
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    virDBusTypeStack *stack = NULL;
    size_t nstack = 0;
    size_t siglen;
    char *contsig = NULL;
    const char *vsig;
    DBusMessageIter *newiter = NULL;
    DBusMessageIter *iter = rootiter;

    VIR_DEBUG("rootiter=%p types=%s", rootiter, types);

    if (!types)
        return 0;

    narray = (size_t)-1;
    nstruct = strlen(types);

    for (;;) {
        const char *t;

        VIR_DEBUG("Loop stack=%zu array=%zu struct=%zu type='%s'",
                  nstack, narray, nstruct, types);
        if (narray == 0 ||
            (narray == (size_t)-1 &&
             nstruct == 0)) {
            DBusMessageIter *thisiter = iter;
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            arrayref = false;
            arrayptr = NULL;
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            VIR_DEBUG("Popping iter=%p", iter);
            if (nstack == 0)
                break;
            if (virDBusTypeStackPop(&stack, &nstack, &iter,
                                    &types, &nstruct, &narray) < 0)
                goto cleanup;
            VIR_DEBUG("Popped iter=%p", iter);

            if (!dbus_message_iter_close_container(iter, thisiter)) {
                if (thisiter != rootiter)
                    VIR_FREE(thisiter);
                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                               _("Cannot close container iterator"));
                goto cleanup;
            }
            if (thisiter != rootiter)
                VIR_FREE(thisiter);
            continue;
        }

        t = types;
        if (narray != (size_t)-1) {
            narray--;
        } else {
            types++;
            nstruct--;
        }

        switch (*t) {
        case DBUS_TYPE_BYTE:
            SET_NEXT_VAL(unsigned char, int, *t, "%d");
            break;

        case DBUS_TYPE_BOOLEAN:
            SET_NEXT_VAL(dbus_bool_t, int, *t, "%d");
            break;

        case DBUS_TYPE_INT16:
            SET_NEXT_VAL(dbus_int16_t, int, *t, "%d");
            break;

        case DBUS_TYPE_UINT16:
            SET_NEXT_VAL(dbus_uint16_t, unsigned int, *t, "%d");
            break;

        case DBUS_TYPE_INT32:
            SET_NEXT_VAL(dbus_int32_t, int, *t, "%d");
            break;

        case DBUS_TYPE_UINT32:
            SET_NEXT_VAL(dbus_uint32_t, unsigned int, *t, "%u");
            break;

        case DBUS_TYPE_INT64:
            SET_NEXT_VAL(dbus_int64_t, long long, *t, "%lld");
            break;

        case DBUS_TYPE_UINT64:
            SET_NEXT_VAL(dbus_uint64_t, unsigned long long, *t, "%llu");
            break;

        case DBUS_TYPE_DOUBLE:
            SET_NEXT_VAL(double, double, *t, "%lf");
            break;

        case DBUS_TYPE_STRING:
        case DBUS_TYPE_OBJECT_PATH:
        case DBUS_TYPE_SIGNATURE:
            SET_NEXT_VAL(char *, char *, *t, "%s");
            break;

        case DBUS_TYPE_ARRAY:
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            arrayptr = NULL;
            if (t[1] == '&') {
                VIR_DEBUG("Got array ref");
                t++;
                types++;
                nstruct--;
                arrayref = true;
            } else {
                VIR_DEBUG("Got array non-ref");
                arrayref = false;
            }

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            if (virDBusSignatureLength(t + 1, &siglen) < 0)
                goto cleanup;

            if (VIR_STRNDUP(contsig, t + 1, siglen) < 0)
                goto cleanup;

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            if (arrayref && (strlen(contsig) > 1 ||
                             !virDBusIsBasicType(*contsig))) {
                virReportError(VIR_ERR_INTERNAL_ERROR,
                               _("Got array ref but '%s' is not a single basic type"),
                               contsig);
                goto cleanup;
            }

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            if (narray == (size_t)-1) {
                types += siglen;
                nstruct -= siglen;
            }

            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            VIR_DEBUG("Contsig '%s' '%zu'", contsig, siglen);
            if (!dbus_message_iter_open_container(iter, DBUS_TYPE_ARRAY,
                                                  contsig, newiter))
                goto cleanup;
            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
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                                     nstruct, narray) < 0) {
                VIR_FREE(newiter);
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                goto cleanup;
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            }
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            VIR_FREE(contsig);
            iter = newiter;
            newiter = NULL;
            types = t + 1;
            nstruct = siglen;
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            narray = (size_t)va_arg(args, int);
            if (arrayref)
                arrayptr = va_arg(args, void *);
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            break;

        case DBUS_TYPE_VARIANT:
            vsig = va_arg(args, const char *);
            if (!vsig) {
                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                               _("Missing variant type signature"));
                goto cleanup;
            }
            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            if (!dbus_message_iter_open_container(iter, DBUS_TYPE_VARIANT,
                                                  vsig, newiter))
                goto cleanup;
            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
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                                     nstruct, narray) < 0) {
                VIR_FREE(newiter);
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                goto cleanup;
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            }
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            iter = newiter;
            newiter = NULL;
            types = vsig;
            nstruct = strlen(types);
            narray = (size_t)-1;
            break;

        case DBUS_STRUCT_BEGIN_CHAR:
        case DBUS_DICT_ENTRY_BEGIN_CHAR:
            if (virDBusSignatureLength(t, &siglen) < 0)
                goto cleanup;

            if (VIR_STRNDUP(contsig, t + 1, siglen - 1) < 0)
                goto cleanup;

            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            VIR_DEBUG("Contsig '%s' '%zu'", contsig, siglen);
            if (!dbus_message_iter_open_container(iter,
                                                  *t == DBUS_STRUCT_BEGIN_CHAR ?
                                                  DBUS_TYPE_STRUCT : DBUS_TYPE_DICT_ENTRY,
                                                  NULL, newiter))
                goto cleanup;
            if (narray == (size_t)-1) {
                types += siglen - 1;
                nstruct -= siglen - 1;
            }

            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
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                                     nstruct, narray) < 0) {
                VIR_FREE(newiter);
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                goto cleanup;
738
            }
739 740 741 742 743 744 745 746 747 748 749
            VIR_FREE(contsig);
            iter = newiter;
            newiter = NULL;
            types = t + 1;
            nstruct = siglen - 2;
            narray = (size_t)-1;

            break;

        default:
            virReportError(VIR_ERR_INTERNAL_ERROR,
750 751 752
                           _("Unknown type '%c' in signature '%s'"),
                           *t, types);
            goto cleanup;
753 754 755 756 757 758
        }
    }

    ret = 0;

cleanup:
759 760 761 762 763 764 765 766 767 768 769
    while (nstack > 0) {
        DBusMessageIter *thisiter = iter;
        VIR_DEBUG("Popping iter=%p", iter);
        ignore_value(virDBusTypeStackPop(&stack, &nstack, &iter,
                                         &types, &nstruct, &narray));
        VIR_DEBUG("Popped iter=%p", iter);

        if (thisiter != rootiter)
            VIR_FREE(thisiter);
    }

770 771 772 773 774 775 776 777 778 779
    virDBusTypeStackFree(&stack, &nstack);
    VIR_FREE(contsig);
    VIR_FREE(newiter);
    return ret;
}
# undef SET_NEXT_VAL


# define GET_NEXT_VAL(dbustype, vargtype, fmt)                          \
    do {                                                                \
780 781 782 783 784 785 786 787 788 789
        dbustype *x;                                                    \
        if (arrayref) {                                                 \
            vargtype **xptrptr = arrayptr;                              \
            if (VIR_EXPAND_N(*xptrptr, *narrayptr, 1) < 0)              \
                goto cleanup;                                           \
            x = (dbustype *)(*xptrptr + (*narrayptr - 1));              \
            VIR_DEBUG("Expanded to %zu", *narrayptr);                   \
        } else {                                                        \
            x = (dbustype *)va_arg(args, vargtype *);                   \
        }                                                               \
790 791 792 793 794 795 796 797 798 799 800 801 802 803
        dbus_message_iter_get_basic(iter, x);                           \
        VIR_DEBUG("Read basic type '" #dbustype "' varg '" #vargtype    \
                  "' val '" fmt "'", (vargtype)*x);                     \
    } while (0)


static int
virDBusMessageIterDecode(DBusMessageIter *rootiter,
                         const char *types,
                         va_list args)
{
    int ret = -1;
    size_t narray;
    size_t nstruct;
804 805 806
    bool arrayref = false;
    void *arrayptr = NULL;
    size_t *narrayptr = 0;
807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832
    virDBusTypeStack *stack = NULL;
    size_t nstack = 0;
    size_t siglen;
    char *contsig = NULL;
    const char *vsig;
    DBusMessageIter *newiter = NULL;
    DBusMessageIter *iter = rootiter;

    VIR_DEBUG("rootiter=%p types=%s", rootiter, types);

    if (!types)
        return 0;

    narray = (size_t)-1;
    nstruct = strlen(types);

    for (;;) {
        const char *t;
        bool advanceiter = true;

        VIR_DEBUG("Loop stack=%zu array=%zu struct=%zu type='%s'",
                  nstack, narray, nstruct, types);
        if (narray == 0 ||
            (narray == (size_t)-1 &&
             nstruct == 0)) {
            DBusMessageIter *thisiter = iter;
833 834
            arrayref = false;
            arrayptr = NULL;
835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864
            VIR_DEBUG("Popping iter=%p", iter);
            if (nstack == 0)
                break;
            if (virDBusTypeStackPop(&stack, &nstack, &iter,
                                    &types, &nstruct, &narray) < 0)
                goto cleanup;
            VIR_DEBUG("Popped iter=%p types=%s", iter, types);
            if (thisiter != rootiter)
                VIR_FREE(thisiter);
            if (!(narray == 0 ||
                  (narray == (size_t)-1 &&
                   nstruct == 0)) &&
                !dbus_message_iter_next(iter)) {
                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                               _("Not enough fields in message for signature"));
                goto cleanup;
            }
            continue;
        }

        t = types;
        if (narray != (size_t)-1) {
            narray--;
        } else {
            types++;
            nstruct--;
        }

        switch (*t) {
        case DBUS_TYPE_BYTE:
865
            GET_NEXT_VAL(unsigned char, unsigned char, "%d");
866 867 868 869 870 871 872
            break;

        case DBUS_TYPE_BOOLEAN:
            GET_NEXT_VAL(dbus_bool_t, int, "%d");
            break;

        case DBUS_TYPE_INT16:
873
            GET_NEXT_VAL(dbus_int16_t, short, "%d");
874 875 876
            break;

        case DBUS_TYPE_UINT16:
877
            GET_NEXT_VAL(dbus_uint16_t, unsigned short, "%d");
878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903
            break;

        case DBUS_TYPE_INT32:
            GET_NEXT_VAL(dbus_uint32_t, int, "%d");
            break;

        case DBUS_TYPE_UINT32:
            GET_NEXT_VAL(dbus_uint32_t, unsigned int, "%u");
            break;

        case DBUS_TYPE_INT64:
            GET_NEXT_VAL(dbus_uint64_t, long long, "%lld");
            break;

        case DBUS_TYPE_UINT64:
            GET_NEXT_VAL(dbus_uint64_t, unsigned long long, "%llu");
            break;

        case DBUS_TYPE_DOUBLE:
            GET_NEXT_VAL(double, double, "%lf");
            break;

        case DBUS_TYPE_STRING:
        case DBUS_TYPE_OBJECT_PATH:
        case DBUS_TYPE_SIGNATURE:
            do {
904 905 906 907 908 909 910 911 912 913
                char **x;
                if (arrayref) {
                    char ***xptrptr = arrayptr;
                    if (VIR_EXPAND_N(*xptrptr, *narrayptr, 1) < 0)
                        goto cleanup;
                    x = (char **)(*xptrptr + (*narrayptr - 1));
                    VIR_DEBUG("Expanded to %zu", *narrayptr);
                } else {
                    x = (char **)va_arg(args, char **);
                }
914 915 916 917 918 919 920 921 922 923
                char *s;
                dbus_message_iter_get_basic(iter, &s);
                if (VIR_STRDUP(*x, s) < 0)
                    goto cleanup;
                VIR_DEBUG("Read basic type 'char *' varg 'char **'"
                          "' val '%s'", *x);
            } while (0);
            break;

        case DBUS_TYPE_ARRAY:
924 925 926 927 928 929 930 931 932 933 934 935
            arrayptr = NULL;
            if (t[1] == '&') {
                VIR_DEBUG("Got array ref");
                t++;
                types++;
                nstruct--;
                arrayref = true;
            } else {
                VIR_DEBUG("Got array non-ref");
                arrayref = false;
            }

936 937 938 939 940 941 942
            advanceiter = false;
            if (virDBusSignatureLength(t + 1, &siglen) < 0)
                goto cleanup;

            if (VIR_STRNDUP(contsig, t + 1, siglen) < 0)
                goto cleanup;

943 944 945 946 947 948 949 950
            if (arrayref && (strlen(contsig) > 1 ||
                             !virDBusIsBasicType(*contsig))) {
                virReportError(VIR_ERR_INTERNAL_ERROR,
                               _("Got array ref but '%s' is not a single basic type"),
                               contsig);
                goto cleanup;
            }

951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968
            if (narray == (size_t)-1) {
                types += siglen;
                nstruct -= siglen;
            }

            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            VIR_DEBUG("Contsig '%s' '%zu' '%s'", contsig, siglen, types);
            dbus_message_iter_recurse(iter, newiter);
            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
                                     nstruct, narray) < 0)
                goto cleanup;
            VIR_FREE(contsig);
            iter = newiter;
            newiter = NULL;
            types = t + 1;
            nstruct = siglen;
969 970 971 972 973 974 975 976
            if (arrayref) {
                narrayptr = va_arg(args, size_t *);
                arrayptr = va_arg(args, void *);
                *narrayptr = 0;
                *(char **)arrayptr = NULL;
            } else {
                narray = va_arg(args, int);
            }
977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035
            break;

        case DBUS_TYPE_VARIANT:
            advanceiter = false;
            vsig = va_arg(args, const char *);
            if (!vsig) {
                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                               _("Missing variant type signature"));
                goto cleanup;
            }
            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            dbus_message_iter_recurse(iter, newiter);
            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
                                     nstruct, narray) < 0) {
                VIR_DEBUG("Push failed");
                goto cleanup;
            }
            iter = newiter;
            newiter = NULL;
            types = vsig;
            nstruct = strlen(types);
            narray = (size_t)-1;
            break;

        case DBUS_STRUCT_BEGIN_CHAR:
        case DBUS_DICT_ENTRY_BEGIN_CHAR:
            advanceiter = false;
            if (virDBusSignatureLength(t, &siglen) < 0)
                goto cleanup;

            if (VIR_STRNDUP(contsig, t + 1, siglen - 1) < 0)
                goto cleanup;

            if (VIR_ALLOC(newiter) < 0)
                goto cleanup;
            VIR_DEBUG("Contsig '%s' '%zu'", contsig, siglen);
            dbus_message_iter_recurse(iter, newiter);
            if (narray == (size_t)-1) {
                types += siglen - 1;
                nstruct -= siglen - 1;
            }

            if (virDBusTypeStackPush(&stack, &nstack,
                                     iter, types,
                                     nstruct, narray) < 0)
                goto cleanup;
            VIR_FREE(contsig);
            iter = newiter;
            newiter = NULL;
            types = t + 1;
            nstruct = siglen - 2;
            narray = (size_t)-1;

            break;

        default:
            virReportError(VIR_ERR_INTERNAL_ERROR,
1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046
                           _("Unknown type '%c' in signature '%s'"),
                           *t, types);
            goto cleanup;
        }

        if (arrayref) {
            if (*t == '&' ||
                dbus_message_iter_has_next(iter))
                narray = 1;
            else
                narray = 0;
1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148
        }

        VIR_DEBUG("After stack=%zu array=%zu struct=%zu type='%s'",
                  nstack, narray, nstruct, types);
        if (advanceiter &&
            !(narray == 0 ||
              (narray == (size_t)-1 &&
               nstruct == 0)) &&
            !dbus_message_iter_next(iter)) {
            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                           _("Not enough fields in message for signature"));
            goto cleanup;
        }
    }

    if (dbus_message_iter_has_next(iter)) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Too many fields in message for signature"));
        goto cleanup;
    }

    ret = 0;

cleanup:
    virDBusTypeStackFree(&stack, &nstack);
    VIR_FREE(contsig);
    VIR_FREE(newiter);
    return ret;
}
# undef GET_NEXT_VAL

int
virDBusMessageEncodeArgs(DBusMessage* msg,
                         const char *types,
                         va_list args)
{
    DBusMessageIter iter;
    int ret = -1;

    memset(&iter, 0, sizeof(iter));

    dbus_message_iter_init_append(msg, &iter);

    ret = virDBusMessageIterEncode(&iter, types, args);

    return ret;
}


int virDBusMessageDecodeArgs(DBusMessage* msg,
                             const char *types,
                             va_list args)
{
    DBusMessageIter iter;
    int ret = -1;

    if (!dbus_message_iter_init(msg, &iter)) {
        if (*types != '\0') {
            virReportError(VIR_ERR_INTERNAL_ERROR,
                           _("No args present for signature %s"),
                           types);
        } else {
            ret = 0;
        }
        goto cleanup;
    }

    ret = virDBusMessageIterDecode(&iter, types, args);

cleanup:
    return ret;
}


int virDBusMessageEncode(DBusMessage* msg,
                         const char *types,
                         ...)
{
    int ret;
    va_list args;
    va_start(args, types);
    ret = virDBusMessageEncodeArgs(msg, types, args);
    va_end(args);
    return ret;
}


int virDBusMessageDecode(DBusMessage* msg,
                         const char *types,
                         ...)
{
    int ret;
    va_list args;
    va_start(args, types);
    ret = virDBusMessageDecodeArgs(msg, types, args);
    va_end(args);
    return ret;
}

# define VIR_DBUS_METHOD_CALL_TIMEOUT_MILLIS 30 * 1000

/**
1149 1150
 * virDBusCreateMethodV:
 * @call: pointer to be filled with a method call message
1151 1152
 * @destination: bus identifier of the target service
 * @path: object path of the target service
E
Eric Blake 已提交
1153
 * @iface: the interface of the object
1154 1155
 * @member: the name of the method in the interface
 * @types: type signature for following method arguments
1156
 * @args: method arguments
1157
 *
1158 1159
 * This creates a DBus method call message and saves a
 * pointer to it in @call. The @destination, @path, @iface
1160 1161
 * and @member parameters identify the object method to
 * be invoked. The optional @replyout parameter will be
1162 1163
 * filled with any reply to the method call. The method
 * can be later invoked using virDBusCall.
1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192
 *
 * The @types parameter is a DBus signature describing
 * the method call parameters which will be provided
 * as variadic args. Each character in @types must
 * correspond to one of the following DBus codes for
 * basic types:
 *
 * 'y' - 8-bit byte, promoted to an 'int'
 * 'b' - bool value, promoted to an 'int'
 * 'n' - 16-bit signed integer, promoted to an 'int'
 * 'q' - 16-bit unsigned integer, promoted to an 'int'
 * 'i' - 32-bit signed integer, passed as an 'int'
 * 'u' - 32-bit unsigned integer, passed as an 'int'
 * 'x' - 64-bit signed integer, passed as a 'long long'
 * 't' - 64-bit unsigned integer, passed as an 'unsigned long long'
 * 'd' - 8-byte floating point, passed as a 'double'
 * 's' - NUL-terminated string, in UTF-8
 * 'o' - NUL-terminated string, representing a valid object path
 * 'g' - NUL-terminated string, representing a valid type signature
 *
 * or use one of the compound types
 *
 * 'a' - array of values
 * 'v' - a variadic type.
 * '(' - start of a struct
 * ')' - end of a struct
 * '{' - start of a dictionary entry (pair of types)
 * '}' - start of a dictionary entry (pair of types)
 *
E
Eric Blake 已提交
1193 1194 1195
 * At this time, there is no support for Unix fd's ('h'), which only
 * newer DBus supports.
 *
1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
 * Passing values in variadic args for basic types is
 * simple, the value is just passed directly using the
 * corresponding C type listed against the type code
 * above. Note how any integer value smaller than an
 * 'int' is promoted to an 'int' by the C rules for
 * variadic args.
 *
 * Passing values in variadic args for compound types
 * requires a little further explanation.
 *
 * - Variant: the first arg is a string containing
 *   the type signature for the values to be stored
 *   inside the variant. This is then followed by
 *   the values corresponding to the type signature
 *   in the normal manner.
 *
 * - Array: when 'a' appears in a type signature, it
 *   must be followed by a single type describing the
 *   array element type. For example 'as' is an array
 *   of strings. 'a(is)' is an array of structs, each
 *   struct containing an int and a string.
 *
 *   The first variadic arg for an array, is an 'int'
 *   specifying the number of elements in the array.
 *   This is then followed by the values for the array
 *
 * - Struct: when a '(' appears in a type signature,
 *   it must be followed by one or more types describing
 *   the elements in the array, terminated by a ')'.
 *
 * - Dict entry: when a '{' appears in a type signature it
 *   must be followed by exactly two types, one describing
 *   the type of the hash key, the other describing the
 *   type of the hash entry. The hash key type must be
 *   a basic type, not a compound type.
 *
 * Example signatures, with their corresponding variadic
 * args:
 *
 * - "biiss" - some basic types
 *
 *     (true, 7, 42, "hello", "world")
 *
 * - "as" - an array with a basic type element
 *
 *     (3, "one", "two", "three")
 *
 * - "a(is)" - an array with a struct element
 *
 *     (3, 1, "one", 2, "two", 3, "three")
 *
 * - "svs" - some basic types with a variant as an int
 *
 *     ("hello", "i", 3, "world")
 *
 * - "svs" - some basic types with a variant as an array of ints
 *
 *     ("hello", "ai", 4, 1, 2, 3, 4, "world")
 *
 * - "a{ss}" - a hash table (aka array + dict entry)
 *
 *     (3, "title", "Mr", "forename", "Joe", "surname", "Bloggs")
 *
 * - "a{sv}" - a hash table (aka array + dict entry)
 *
 *     (3, "email", "s", "joe@blogs.com", "age", "i", 35,
 *      "address", "as", 3, "Some house", "Some road", "some city")
 */
1264 1265 1266 1267 1268 1269 1270
int virDBusCreateMethodV(DBusMessage **call,
                         const char *destination,
                         const char *path,
                         const char *iface,
                         const char *member,
                         const char *types,
                         va_list args)
1271 1272 1273
{
    int ret = -1;

1274 1275 1276 1277
    if (!(*call = dbus_message_new_method_call(destination,
                                               path,
                                               iface,
                                               member))) {
1278 1279 1280 1281
        virReportOOMError();
        goto cleanup;
    }

1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316
    if (virDBusMessageEncodeArgs(*call, types, args) < 0) {
        dbus_message_unref(*call);
        *call = NULL;
        goto cleanup;
    }

    ret = 0;
 cleanup:
    return ret;
}


/**
 * virDBusCreateMethod:
 * @call: pointer to be filled with a method call message
 * @destination: bus identifier of the target service
 * @path: object path of the target service
 * @iface: the interface of the object
 * @member: the name of the method in the interface
 * @types: type signature for following method arguments
 * @...: method arguments
 *
 * See virDBusCreateMethodV for a description of the
 * behaviour of this method.
 */
int virDBusCreateMethod(DBusMessage **call,
                        const char *destination,
                        const char *path,
                        const char *iface,
                        const char *member,
                        const char *types, ...)
{
    va_list args;
    int ret;

1317
    va_start(args, types);
1318 1319
    ret = virDBusCreateMethodV(call, destination, path,
                               iface, member, types, args);
1320 1321
    va_end(args);

1322 1323 1324 1325
    return ret;
}


1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385
/**
 * virDBusCreateReplyV:
 * @reply: pointer to be filled with a method reply message
 * @types: type signature for following method arguments
 * @args: method arguments
 *
 * This creates a DBus method reply message and saves a
 * pointer to it in @reply.
 *
 * The @types parameter is a DBus signature describing
 * the method call parameters which will be provided
 * as variadic args. See virDBusCreateMethodV for a
 * description of this parameter.
 */
int virDBusCreateReplyV(DBusMessage **reply,
                        const char *types,
                        va_list args)
{
    int ret = -1;

    if (!(*reply = dbus_message_new(DBUS_MESSAGE_TYPE_METHOD_RETURN))) {
        virReportOOMError();
        goto cleanup;
    }

    if (virDBusMessageEncodeArgs(*reply, types, args) < 0) {
        dbus_message_unref(*reply);
        *reply = NULL;
        goto cleanup;
    }

    ret = 0;
 cleanup:
    return ret;
}


/**
 * virDBusCreateReply:
 * @reply: pointer to be filled with a method reply message
 * @types: type signature for following method arguments
 * @...: method arguments
 *
 * See virDBusCreateReplyV for a description of the
 * behaviour of this method.
 */
int virDBusCreateReply(DBusMessage **reply,
                       const char *types, ...)
{
    va_list args;
    int ret;

    va_start(args, types);
    ret = virDBusCreateReplyV(reply, types, args);
    va_end(args);

    return ret;
}


1386 1387 1388 1389 1390
/**
 * virDBusCall:
 * @conn: a DBus connection
 * @call: pointer to a message to send
 * @replyout: pointer to receive reply message, or NULL
1391
 * @error: pointer to receive error message
1392 1393 1394 1395 1396 1397 1398
 *
 * This invokes a method encoded in @call on a remote
 * service on the DBus bus @conn. The optional @replyout
 * parameter will be filled with any reply to the method
 * call. The virDBusMethodReply method can be used to
 * decode the return values.
 *
1399 1400 1401 1402 1403 1404
 * If @error is NULL then a libvirt error will be raised
 * when a DBus error is received and the return value will
 * be -1. If @error is non-NULL then any DBus error will
 * be saved into that object and the return value will
 * be 0.
 *
1405 1406 1407 1408
 * Returns 0 on success, or -1 upon error
 */
int virDBusCall(DBusConnection *conn,
                DBusMessage *call,
1409 1410
                DBusMessage **replyout,
                DBusError *error)
1411 1412
{
    DBusMessage *reply = NULL;
1413
    DBusError localerror;
1414 1415
    int ret = -1;

1416 1417
    if (!error)
        dbus_error_init(&localerror);
1418 1419 1420 1421

    if (!(reply = dbus_connection_send_with_reply_and_block(conn,
                                                            call,
                                                            VIR_DBUS_METHOD_CALL_TIMEOUT_MILLIS,
1422 1423 1424 1425 1426 1427
                                                            error ? error : &localerror))) {
        if (error)
            ret = 0;
        else
            virReportDBusServiceError(localerror.message ? localerror.message : "unknown error",
                                      localerror.name);
1428 1429 1430 1431 1432
        goto cleanup;
    }

    ret = 0;

1433
 cleanup:
1434 1435
    if (!error)
        dbus_error_free(&localerror);
1436 1437 1438 1439 1440 1441 1442 1443 1444 1445
    if (reply) {
        if (ret == 0 && replyout)
            *replyout = reply;
        else
            dbus_message_unref(reply);
    }
    return ret;
}


1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469
/**
 * virDBusCallMethod:
 * @conn: a DBus connection
 * @replyout: pointer to receive reply message, or NULL
 * @destination: bus identifier of the target service
 * @path: object path of the target service
 * @iface: the interface of the object
 * @member: the name of the method in the interface
 * @types: type signature for following method arguments
 * @...: method arguments
 *
 * This invokes a method on a remote service on the
 * DBus bus @conn. The @destination, @path, @iface
 * and @member parameters identify the object method to
 * be invoked. The optional @replyout parameter will be
 * filled with any reply to the method call. The
 * virDBusMethodReply method can be used to decode the
 * return values.
 *
 * The @types parameter is a DBus signature describing
 * the method call parameters which will be provided
 * as variadic args. See virDBusCreateMethodV for a
 * description of this parameter.
 *
1470 1471 1472 1473 1474 1475 1476 1477 1478 1479
 *
 * If @error is NULL then a libvirt error will be raised
 * when a DBus error is received and the return value will
 * be -1. If @error is non-NULL then any DBus error will
 * be saved into that object and the return value will
 * be 0. If an error occurs while encoding method args
 * the return value will always be -1 regardless of whether
 * @error is set.
 *
 * Returns 0 on success, or -1 upon error
1480 1481 1482
 */
int virDBusCallMethod(DBusConnection *conn,
                      DBusMessage **replyout,
1483
                      DBusError *error,
1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502
                      const char *destination,
                      const char *path,
                      const char *iface,
                      const char *member,
                      const char *types, ...)
{
    DBusMessage *call = NULL;
    int ret = -1;
    va_list args;

    va_start(args, types);
    ret = virDBusCreateMethodV(&call, destination, path,
                               iface, member, types, args);
    va_end(args);
    if (ret < 0)
        goto cleanup;

    ret = -1;

1503
    ret = virDBusCall(conn, call, replyout, error);
1504 1505 1506 1507 1508 1509 1510 1511

 cleanup:
    if (call)
        dbus_message_unref(call);
    return ret;
}


1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
/**
 * virDBusMessageRead:
 * @msg: the reply to decode
 * @types: type signature for following return values
 * @...: pointers in which to store return values
 *
 * The @types type signature is the same format as
 * that used for the virDBusCallMethod. The difference
 * is that each variadic parameter must be a pointer to
 * be filled with the values. eg instead of passing an
 * 'int', pass an 'int *'.
 *
 */
int virDBusMessageRead(DBusMessage *msg,
                       const char *types, ...)
{
    va_list args;
    int ret;

    va_start(args, types);
    ret = virDBusMessageDecodeArgs(msg, types, args);
    va_end(args);

    return ret;
}

1538
static int virDBusIsServiceInList(const char *listMethod, const char *name)
1539 1540 1541 1542 1543 1544 1545 1546 1547
{
    DBusConnection *conn;
    DBusMessage *reply = NULL;
    DBusMessageIter iter, sub;
    int ret = -1;

    if (!virDBusHasSystemBus())
        return -2;

1548 1549
    if (!(conn = virDBusGetSystemBus()))
        return -1;
1550 1551 1552

    if (virDBusCallMethod(conn,
                          &reply,
1553
                          NULL,
1554 1555 1556
                          "org.freedesktop.DBus",
                          "/org/freedesktop/DBus",
                          "org.freedesktop.DBus",
1557
                          listMethod,
C
Cédric Bosdonnat 已提交
1558
                          NULL) < 0)
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586
        return ret;

    if (!dbus_message_iter_init(reply, &iter) ||
        dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY) {
        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
                       _("Reply message incorrect"));
        goto cleanup;
    }

    ret = -2;
    dbus_message_iter_recurse(&iter, &sub);
    while (dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING) {
        const char *service = NULL;

        dbus_message_iter_get_basic(&sub, &service);
        dbus_message_iter_next(&sub);

        if (STREQ(service, name)) {
            ret = 0;
            break;
        }
    }

 cleanup:
    dbus_message_unref(reply);
    return ret;
}

1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600
/**
 * virDBusIsServiceEnabled:
 * @name: service name
 *
 * Returns 0 if service is available, -1 on fatal error, or -2 if service is not available
 */
int virDBusIsServiceEnabled(const char *name)
{
    int ret = virDBusIsServiceInList("ListActivatableNames", name);

    VIR_DEBUG("Service %s is %s", name, ret ? "unavailable" : "available");

    return ret;
}
1601

1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616
/**
 * virDBusIsServiceRegistered
 * @name: service name
 *
 * Retruns 0 if service is registered, -1 on fatal error, or -2 if service is not registered
 */
int virDBusIsServiceRegistered(const char *name)
{
    int ret = virDBusIsServiceInList("ListNames", name);

    VIR_DEBUG("Service %s is %s", name, ret ? "not registered" : "registered");

    return ret;
}

1617
#else /* ! WITH_DBUS */
1618 1619 1620 1621 1622
void virDBusSetSharedBus(bool shared ATTRIBUTE_UNUSED)
{
    /* nothing */
}

1623 1624
DBusConnection *virDBusGetSystemBus(void)
{
1625 1626
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
1627 1628 1629
    return NULL;
}

1630 1631 1632 1633 1634 1635 1636 1637

bool
virDBusHasSystemBus(void)
{
    VIR_DEBUG("DBus support not compiled into this binary");
    return false;
}

1638 1639 1640 1641
void virDBusCloseSystemBus(void)
{
    /* nothing */
}
1642

1643 1644 1645 1646 1647 1648
DBusConnection *virDBusGetSessionBus(void)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return NULL;
}
1649

1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674
int virDBusCreateMethod(DBusMessage **call ATTRIBUTE_UNUSED,
                        const char *destination ATTRIBUTE_UNUSED,
                        const char *path ATTRIBUTE_UNUSED,
                        const char *iface ATTRIBUTE_UNUSED,
                        const char *member ATTRIBUTE_UNUSED,
                        const char *types ATTRIBUTE_UNUSED, ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

int virDBusCreateMethodV(DBusMessage **call ATTRIBUTE_UNUSED,
                         const char *destination ATTRIBUTE_UNUSED,
                         const char *path ATTRIBUTE_UNUSED,
                         const char *iface ATTRIBUTE_UNUSED,
                         const char *member ATTRIBUTE_UNUSED,
                         const char *types ATTRIBUTE_UNUSED,
                         va_list args ATTRIBUTE_UNUSED)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691
int virDBusCreateReplyV(DBusMessage **reply ATTRIBUTE_UNUSED,
                        const char *types ATTRIBUTE_UNUSED,
                        va_list args ATTRIBUTE_UNUSED)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

int virDBusCreateReply(DBusMessage **reply ATTRIBUTE_UNUSED,
                       const char *types ATTRIBUTE_UNUSED, ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

1692 1693
int virDBusCall(DBusConnection *conn ATTRIBUTE_UNUSED,
                DBusMessage *call ATTRIBUTE_UNUSED,
1694 1695
                DBusMessage **reply ATTRIBUTE_UNUSED,
                DBusError *error ATTRIBUTE_UNUSED)
1696 1697 1698 1699 1700 1701
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

1702 1703
int virDBusCallMethod(DBusConnection *conn ATTRIBUTE_UNUSED,
                      DBusMessage **reply ATTRIBUTE_UNUSED,
1704
                      DBusError *error ATTRIBUTE_UNUSED,
1705 1706
                      const char *destination ATTRIBUTE_UNUSED,
                      const char *path ATTRIBUTE_UNUSED,
E
Eric Blake 已提交
1707
                      const char *iface ATTRIBUTE_UNUSED,
1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723
                      const char *member ATTRIBUTE_UNUSED,
                      const char *types ATTRIBUTE_UNUSED, ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

int virDBusMessageRead(DBusMessage *msg ATTRIBUTE_UNUSED,
                       const char *types ATTRIBUTE_UNUSED, ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741
int virDBusMessageEncode(DBusMessage* msg ATTRIBUTE_UNUSED,
                         const char *types ATTRIBUTE_UNUSED,
                         ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

int virDBusMessageDecode(DBusMessage* msg ATTRIBUTE_UNUSED,
                         const char *types ATTRIBUTE_UNUSED,
                         ...)
{
    virReportError(VIR_ERR_INTERNAL_ERROR,
                   "%s", _("DBus support not compiled into this binary"));
    return -1;
}

1742 1743 1744 1745 1746 1747
int virDBusIsServiceEnabled(const char *name ATTRIBUTE_UNUSED)
{
    VIR_DEBUG("DBus support not compiled into this binary");
    return -2;
}

1748 1749 1750 1751 1752 1753
int virDBusIsServiceRegistered(const char *name ATTRIBUTE_UNUSED)
{
    VIR_DEBUG("DBus support not compiled into this binary");
    return -2;
}

1754
#endif /* ! WITH_DBUS */