libvirt/src/util/virsystemd.c
Daniel P. Berrange 6bd8860001 Don't ignore all dbus connection errors
Previous commit

  commit 7ada155cdf
  Author: Gao feng <gaofeng@cn.fujitsu.com>
  Date:   Wed Sep 11 11:15:02 2013 +0800

    DBus: introduce virDBusIsServiceEnabled

Made the cgroups code fallback to non-systemd based setup
when dbus is not running. It was too big a hammer though,
as it did not check what error code was received when the
dbus connection failed. Thus it silently ignored serious
errors from dbus such as "too many client connections",
which should always be treated as fatal.

We only want to ignore errors if the dbus unix socket does
not exist, or if nothing is listening on it.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-10-14 10:33:10 +01:00

305 lines
8.9 KiB
C

/*
* virsystemd.c: helpers for using systemd APIs
*
* Copyright (C) 2013 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/>.
*
*/
#include <config.h>
#include "virsystemd.h"
#include "virdbus.h"
#include "virstring.h"
#include "viralloc.h"
#include "virutil.h"
#include "virlog.h"
#include "virerror.h"
#define VIR_FROM_THIS VIR_FROM_SYSTEMD
static void virSystemdEscapeName(virBufferPtr buf,
const char *name)
{
static const char hextable[16] = "0123456789abcdef";
#define ESCAPE(c) \
do { \
virBufferAddChar(buf, '\\'); \
virBufferAddChar(buf, 'x'); \
virBufferAddChar(buf, hextable[(c >> 4) & 15]); \
virBufferAddChar(buf, hextable[c & 15]); \
} while (0)
#define VALID_CHARS \
"0123456789" \
"abcdefghijklmnopqrstuvwxyz" \
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
":-_.\\"
if (*name == '.') {
ESCAPE(*name);
name++;
}
while (*name) {
if (*name == '/')
virBufferAddChar(buf, '-');
else if (*name == '-' ||
*name == '\\' ||
!strchr(VALID_CHARS, *name))
ESCAPE(*name);
else
virBufferAddChar(buf, *name);
name++;
}
#undef ESCAPE
#undef VALID_CHARS
}
char *virSystemdMakeScopeName(const char *name,
const char *drivername,
const char *partition)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
if (*partition == '/')
partition++;
virSystemdEscapeName(&buf, partition);
virBufferAddChar(&buf, '-');
virSystemdEscapeName(&buf, drivername);
virBufferAddLit(&buf, "\\x2d");
virSystemdEscapeName(&buf, name);
virBufferAddLit(&buf, ".scope");
if (virBufferError(&buf)) {
virReportOOMError();
return NULL;
}
return virBufferContentAndReset(&buf);
}
char *virSystemdMakeSliceName(const char *partition)
{
virBuffer buf = VIR_BUFFER_INITIALIZER;
if (*partition == '/')
partition++;
virSystemdEscapeName(&buf, partition);
virBufferAddLit(&buf, ".slice");
if (virBufferError(&buf)) {
virReportOOMError();
return NULL;
}
return virBufferContentAndReset(&buf);
}
char *virSystemdMakeMachineName(const char *name,
const char *drivername,
bool privileged)
{
char *machinename = NULL;
char *username = NULL;
if (privileged) {
if (virAsprintf(&machinename, "%s-%s", drivername, name) < 0)
goto cleanup;
} else {
if (!(username = virGetUserName(geteuid())))
goto cleanup;
if (virAsprintf(&machinename, "%s-%s-%s", username, drivername, name) < 0)
goto cleanup;
}
cleanup:
VIR_FREE(username);
return machinename;
}
/**
* virSystemdCreateMachine:
* @name: driver unique name of the machine
* @drivername: name of the virt driver
* @privileged: whether driver is running privileged or per user
* @uuid: globally unique UUID of the machine
* @rootdir: root directory of machine filesystem
* @pidleader: PID of the leader process
* @slice: name of the slice to place the machine in
*
* Returns 0 on success, -1 on fatal error, or -2 if systemd-machine is not available
*/
int virSystemdCreateMachine(const char *name,
const char *drivername,
bool privileged,
const unsigned char *uuid,
const char *rootdir,
pid_t pidleader,
bool iscontainer,
const char *partition)
{
int ret;
DBusConnection *conn;
char *machinename = NULL;
char *creatorname = NULL;
char *slicename = NULL;
ret = virDBusIsServiceEnabled("org.freedesktop.machine1");
if (ret < 0)
return ret;
if (!(conn = virDBusGetSystemBus()))
return -1;
ret = -1;
if (!(machinename = virSystemdMakeMachineName(name, drivername, privileged)))
goto cleanup;
if (virAsprintf(&creatorname, "libvirt-%s", drivername) < 0)
goto cleanup;
if (partition) {
if (!(slicename = virSystemdMakeSliceName(partition)))
goto cleanup;
} else {
if (VIR_STRDUP(slicename, "") < 0)
goto cleanup;
}
/*
* The systemd DBus API we're invoking has the
* following signature
*
* CreateMachine(in s name,
* in ay id,
* in s service,
* in s class,
* in u leader,
* in s root_directory,
* in a(sv) scope_properties,
* out o path);
*
* @name a host unique name for the machine. shows up
* in 'ps' listing & similar
*
* @id: a UUID of the machine, ideally matching /etc/machine-id
* for containers
*
* @service: identifier of the client ie "libvirt-lxc"
*
* @class: either the string "container" or "vm" depending
* on the type of machine
*
* @leader: main PID of the machine, either the host emulator
* process, or the 'init' PID of the container
*
* @root_directory: the root directory of the container, if
* this is known & visible in the host filesystem, or empty string
*
* @scope_properties:an array (not a dict!) of properties that are
* passed on to PID 1 when creating a scope unit for your machine.
* Will allow initial settings for the cgroup & similar.
*
* @path: a bus path returned for the machine object created, to
* allow further API calls to be made against the object.
*/
VIR_DEBUG("Attempting to create machine via systemd");
if (virDBusCallMethod(conn,
NULL,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"CreateMachine",
"sayssusa(sv)",
machinename,
16,
uuid[0], uuid[1], uuid[2], uuid[3],
uuid[4], uuid[5], uuid[6], uuid[7],
uuid[8], uuid[9], uuid[10], uuid[11],
uuid[12], uuid[13], uuid[14], uuid[15],
creatorname,
iscontainer ? "container" : "vm",
(unsigned int)pidleader,
rootdir ? rootdir : "",
1, "Slice", "s",
slicename) < 0)
goto cleanup;
ret = 0;
cleanup:
VIR_FREE(creatorname);
VIR_FREE(machinename);
VIR_FREE(slicename);
return ret;
}
int virSystemdTerminateMachine(const char *name,
const char *drivername,
bool privileged)
{
int ret;
DBusConnection *conn;
char *machinename = NULL;
ret = virDBusIsServiceEnabled("org.freedesktop.machine1");
if (ret < 0)
return ret;
if (!(conn = virDBusGetSystemBus()))
return -1;
ret = -1;
if (!(machinename = virSystemdMakeMachineName(name, drivername, privileged)))
goto cleanup;
/*
* The systemd DBus API we're invoking has the
* following signature
*
* TerminateMachine(in s name);
*
* @name a host unique name for the machine. shows up
* in 'ps' listing & similar
*/
VIR_DEBUG("Attempting to terminate machine via systemd");
if (virDBusCallMethod(conn,
NULL,
"org.freedesktop.machine1",
"/org/freedesktop/machine1",
"org.freedesktop.machine1.Manager",
"TerminateMachine",
"s",
machinename) < 0)
goto cleanup;
ret = 0;
cleanup:
VIR_FREE(machinename);
return ret;
}