[libvirt] [RFC PATCHv2 1/4] config: Adding config driver

This patch adds the source and header for a new driver, named config, which provides the 'config:///' connection URI. This driver provides access to non-domain-related configuration information, such as secret or network definitions. This helps prevent circular dependencies between drivers, including the current case between the QEMU and storage drivers. Signed-off-by: Adam Walters <adam(a)pandorasboxen.com&gt; --- include/libvirt/virterror.h | 2 + src/config/config_driver.c | 238 ++++++++++++++++++++++++++++++++++++++++++++ src/config/config_driver.h | 44 ++++++++ src/util/virerror.c | 2 + 4 files changed, 286 insertions(+) create mode 100644 src/config/config_driver.c create mode 100644 src/config/config_driver.h diff --git a/include/libvirt/virterror.h b/include/libvirt/virterror.h index e31e9c4..0f25a65 100644 --- a/include/libvirt/virterror.h +++ b/include/libvirt/virterror.h @@ -121,6 +121,8 @@ typedef enum { VIR_FROM_ACCESS = 55, /* Error from access control manager */ VIR_FROM_SYSTEMD = 56, /* Error from systemd code */ + VIR_FROM_CONFIG = 57, /* Error from config driver */ + # ifdef VIR_ENUM_SENTINELS VIR_ERR_DOMAIN_LAST # endif diff --git a/src/config/config_driver.c b/src/config/config_driver.c new file mode 100644 index 0000000..c64b532 --- /dev/null +++ b/src/config/config_driver.c @@ -0,0 +1,238 @@ +/* + * config_driver.c: core driver methods for accessing configs + * + * Copyright (C) 2013 Adam Walters + * + * 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: Adam Walters <adam(a)pandorasboxen.com&gt; + */ +#include <config.h> +#include <string.h> + +#include "internal.h" +#include "datatypes.h" +#include "driver.h" +#include "virlog.h" +#include "viralloc.h" +#include "virerror.h" +#include "virstring.h" +#include "viraccessapicheck.h" +#include "nodeinfo.h" +#include "config_driver.h" + +#define VIR_FROM_THIS VIR_FROM_CONFIG + +virConfigDriverPtr config_driver = NULL; + +static int configStateCleanup(void) { + if (config_driver == NULL) + return -1; + + virObjectUnref(config_driver->closeCallbacks); + + virSysinfoDefFree(config_driver->hostsysinfo); + + virMutexDestroy(&config_driver->lock); + VIR_FREE(config_driver); + + return 0; +} + +static int configStateInitialize(bool privileged, + virStateInhibitCallback callback ATTRIBUTE_UNUSED, + void *opaque ATTRIBUTE_UNUSED) +{ + if (!privileged) { + VIR_INFO("Not running privileged, disabling driver"); + return 0; + } + + if (VIR_ALLOC(config_driver) < 0) + return -1; + + if (virMutexInit(&config_driver->lock) < 0) { + VIR_ERROR(_("cannot initialize mutex")); + VIR_FREE(config_driver); + return -1; + } + + config_driver->hostsysinfo = virSysinfoRead(); + + if (!(config_driver->closeCallbacks = virCloseCallbacksNew())) + goto cleanup; + + return 0; + +cleanup: + configStateCleanup(); + return -1; +} + +static int configStateReload(void) { + return 0; +} + +static virDrvOpenStatus configConnectOpen(virConnectPtr conn, + virConnectAuthPtr auth ATTRIBUTE_UNUSED, + unsigned int flags) +{ + virDrvOpenStatus ret = VIR_DRV_OPEN_ERROR; + virCheckFlags(VIR_CONNECT_RO, VIR_DRV_OPEN_ERROR); + + if (conn->uri != NULL) { + /* If URI isn't 'config', decline the connection */ + if (conn->uri->scheme == NULL || + STRNEQ(conn->uri->scheme, "config")) { + ret = VIR_DRV_OPEN_DECLINED; + goto cleanup; + } + + /* Allow remote driver to deal with URIs with hostname set */ + if (conn->uri->server != NULL) { + ret = VIR_DRV_OPEN_DECLINED; + goto cleanup; + } + + if (config_driver == NULL) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("config state driver is not active")); + goto cleanup; + } + } else { + ret = VIR_DRV_OPEN_DECLINED; + goto cleanup; + } + + if (virConnectOpenEnsureACL(conn) < 0) + goto cleanup; + + conn->privateData = config_driver; + + ret = VIR_DRV_OPEN_SUCCESS; +cleanup: + return ret; +} + +static int configConnectClose(virConnectPtr conn ATTRIBUTE_UNUSED) +{ + /* Cleanup callbacks on config_driver */ + /* Set conn->privateData to NULL */ + return 0; +} + +static int +configConnectSupportsFeature(virConnectPtr conn, int feature ATTRIBUTE_UNUSED) +{ + if (virConnectSupportsFeatureEnsureACL(conn) < 0) + return -1; + + return 0; +} + +static const char *configConnectGetType(virConnectPtr conn ATTRIBUTE_UNUSED) { + if (virConnectGetTypeEnsureACL(conn) < 0) + return NULL; + + return "config"; +} + +static int configConnectIsSecure(virConnectPtr conn ATTRIBUTE_UNUSED) +{ + return 1; +} + +static int configConnectIsEncrypted(virConnectPtr conn ATTRIBUTE_UNUSED) +{ + return 0; +} + +static char *configConnectGetHostname(virConnectPtr conn) +{ + if (virConnectGetHostnameEnsureACL(conn) < 0) + return NULL; + + return virGetHostname(); +} + +static char * +configConnectGetSysinfo(virConnectPtr conn, unsigned int flags) +{ + virConfigDriverPtr driver = conn->privateData; + virBuffer buf = VIR_BUFFER_INITIALIZER; + + virCheckFlags(0, NULL); + + if (virConnectGetSysinfoEnsureACL(conn) < 0) + return NULL; + + if (!driver->hostsysinfo) { + return NULL; + } + + if (virSysinfoFormat(&buf, driver->hostsysinfo) < 0) + return NULL; + + if (virBufferError(&buf)) { + virReportOOMError(); + return NULL; + } + + return virBufferContentAndReset(&buf); +} + +static int +configNodeGetInfo(virConnectPtr conn, + virNodeInfoPtr nodeinfo) +{ + if (virNodeGetInfoEnsureACL(conn) < 0) + return -1; + + return nodeGetInfo(nodeinfo); +} + +static int configConnectIsAlive(virConnectPtr conn ATTRIBUTE_UNUSED) +{ + return 1; +} + +static virDriver configDriver = { + .name = "config", + .connectOpen = configConnectOpen, /* 1.2.2 */ + .connectClose = configConnectClose, /* 1.2.2 */ + .connectSupportsFeature = configConnectSupportsFeature, /* 1.2.2 */ + .connectGetType = configConnectGetType, /* 1.2.2 */ + .connectGetHostname = configConnectGetHostname, /* 1.2.2 */ + .connectGetSysinfo = configConnectGetSysinfo, /* 1.2.2 */ + .nodeGetInfo = configNodeGetInfo, /* 1.2.2 */ + .connectIsEncrypted = configConnectIsEncrypted, /* 1.2.2 */ + .connectIsSecure = configConnectIsSecure, /* 1.2.2 */ + .connectIsAlive = configConnectIsAlive, /* 1.2.2 */ +}; + + +static virStateDriver configStateDriver = { + .name = "config", + .stateInitialize = configStateInitialize, + .stateCleanup = configStateCleanup, + .stateReload = configStateReload, + .stateDrvType = VIR_DRV_STATE_DRV_LIBVIRT, +}; + +int configRegister(void) { + virRegisterDriver(&configDriver); + virRegisterStateDriver(&configStateDriver); + return 0; +} diff --git a/src/config/config_driver.h b/src/config/config_driver.h new file mode 100644 index 0000000..c74af71 --- /dev/null +++ b/src/config/config_driver.h @@ -0,0 +1,44 @@ +/* + * config_driver.h: core driver methods for accessing configs + * + * Copyright (C) 2013 Adam Walters + * + * 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: Adam Walters <adam(a)pandorasboxen.com&gt; + */ + +#ifndef __CONFIG_DRIVER_H__ +# define __CONFIG_DRIVER_H__ + +# include "virsysinfo.h" +# include "virclosecallbacks.h" + +typedef struct _virConfigDriver virConfigDriver; +typedef virConfigDriver *virConfigDriverPtr; + +struct _virConfigDriver { + virMutex lock; + + /* Immutable pointer, lockless APIs*/ + virSysinfoDefPtr hostsysinfo; + + /* Immutable pointer, self-locking APIs*/ + virCloseCallbacksPtr closeCallbacks; +}; + +int configRegister(void); + +#endif /* __CONFIG_DRIVER_H__ */ diff --git a/src/util/virerror.c b/src/util/virerror.c index f0c159f..a16a517 100644 --- a/src/util/virerror.c +++ b/src/util/virerror.c @@ -124,6 +124,8 @@ VIR_ENUM_IMPL(virErrorDomain, VIR_ERR_DOMAIN_LAST, "Access Manager", /* 55 */ "Systemd", + + "Config Driver", /* 57 */ ) -- 1.8.5.2