[libvirt] [PATCH] interface: add virInterfaceGetXMLDesc() in udev
Doug Goldstein
cardoe at cardoe.com
Sun Oct 14 22:02:33 UTC 2012
Added support for retrieving the XML defining a specific interface via
the udev based backend to virInterface. Implement the following APIs
for the udev based backend:
* virInterfaceGetXMLDesc()
Note: Does not support bond devices.
---
src/interface/interface_backend_udev.c | 251 ++++++++++++++++++++++++++++++++
1 files changed, 251 insertions(+), 0 deletions(-)
diff --git a/src/interface/interface_backend_udev.c b/src/interface/interface_backend_udev.c
index 1cb6dfe..370f64a 100644
--- a/src/interface/interface_backend_udev.c
+++ b/src/interface/interface_backend_udev.c
@@ -19,6 +19,8 @@
*/
#include <config.h>
+#include <errno.h>
+#include <dirent.h>
#include <libudev.h>
#include "virterror_internal.h"
@@ -489,6 +491,254 @@ err:
return ret;
}
+/**
+ * Helper function for our use of scandir()
+ *
+ * @param entry - directory entry passed by scandir()
+ *
+ * @return 1 if we want to add it to scandir's list, 0 if not.
+ */
+static int
+udevIfaceScanDirFilter(const struct dirent *entry)
+{
+ if (STREQ(entry->d_name, ".") || STREQ(entry->d_name, ".."))
+ return 0;
+
+ return 1;
+}
+
+/**
+ * Frees any memory allocated by udevIfaceGetIfaceDef()
+ *
+ * @param ifacedef - interface to free and cleanup
+ */
+static void
+udevIfaceFreeIfaceDef(virInterfaceDef *ifacedef)
+{
+ if (!ifacedef)
+ return;
+
+ if (ifacedef->type == VIR_INTERFACE_TYPE_BRIDGE) {
+ VIR_FREE(ifacedef->data.bridge.delay);
+ for (int i = 0; i < ifacedef->data.bridge.nbItf; i++) {
+ VIR_FREE(ifacedef->data.bridge.itf[i]);
+ }
+ VIR_FREE(ifacedef->data.bridge.itf);
+ }
+
+ if (ifacedef->type == VIR_INTERFACE_TYPE_VLAN) {
+ VIR_FREE(ifacedef->data.vlan.devname);
+ }
+
+ VIR_FREE(ifacedef->mac);
+ VIR_FREE(ifacedef->name);
+
+ VIR_FREE(ifacedef);
+}
+
+
+static virInterfaceDef * ATTRIBUTE_NONNULL(1)
+udevIfaceGetIfaceDef(struct udev *udev, char *name)
+{
+ struct udev_device *dev;
+ virInterfaceDef *ifacedef;
+ unsigned int mtu;
+ const char *mtu_str;
+ char *vlan_parent_dev = NULL;
+ struct dirent **member_list = NULL;
+ int member_count = 0;
+
+ /* Allocate our interface definition structure */
+ if (VIR_ALLOC(ifacedef) < 0) {
+ virReportOOMError();
+ return NULL;
+ }
+
+ /* Clear our structure and set safe defaults */
+ memset(ifacedef, 0, sizeof(ifacedef));
+ ifacedef->startmode = VIR_INTERFACE_START_UNSPECIFIED;
+ ifacedef->type = VIR_INTERFACE_TYPE_ETHERNET;
+ ifacedef->name = strdup(name);
+
+ if (!ifacedef->name) {
+ virReportOOMError();
+ goto cleanup;
+ }
+
+ /* Lookup the device we've been asked about */
+ dev = udev_device_new_from_subsystem_sysname(udev, "net", name);
+ if (!dev) {
+ virReportError(VIR_ERR_NO_INTERFACE,
+ _("couldn't find interface named '%s'"), name);
+ goto cleanup;
+ }
+
+ /* MAC address */
+ ifacedef->mac = strdup(udev_device_get_sysattr_value(dev, "address"));
+ if (!ifacedef) {
+ virReportOOMError();
+ goto cleanup;
+ }
+
+ /* MTU */
+ mtu_str = udev_device_get_sysattr_value(dev, "mtu");
+ if (virStrToLong_ui(mtu_str, NULL, 10, &mtu) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Could not parse MTU value '%s'"), mtu_str);
+ goto cleanup;
+ }
+ ifacedef->mtu = mtu;
+
+ /* Number of IP protocols this interface has assigned */
+ /* XXX: Do we want a netlink query or a call out to ip or leave it? */
+ ifacedef->nprotos = 0;
+ ifacedef->protos = NULL;
+
+ /* Check if its a VLAN since we can have a VLAN of any of the
+ * other devices */
+ vlan_parent_dev = strrchr(name, '.');
+ if (vlan_parent_dev) {
+ /* Found the VLAN dot */
+ char *vid;
+
+ vlan_parent_dev = strdup(name);
+ if (!vlan_parent_dev) {
+ virReportOOMError();
+ goto cleanup;
+ }
+
+ /* Find the DEVICE.VID separator again */
+ vid = strrchr(vlan_parent_dev, '.');
+ if (!vid) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("failed to find the VID for the VLAN device '%s'"),
+ name);
+ goto cleanup;
+ }
+
+ /* Replace the dot with a NULL so we can have the device and VID */
+ vid[0] = '\0';
+ vid++;
+
+ /* Set our type to VLAN */
+ ifacedef->type = VIR_INTERFACE_TYPE_VLAN;
+
+ /* Set the VLAN specifics */
+ ifacedef->data.vlan.tag = vid;
+ ifacedef->data.vlan.devname = vlan_parent_dev;
+ } else if (STREQ_NULLABLE(udev_device_get_devtype(dev), "bridge")) {
+ /* Check if its a bridge device */
+ char *member_path;
+ const char *stp_str;
+ int stp;
+
+ /* Set our type to Bridge */
+ ifacedef->type = VIR_INTERFACE_TYPE_BRIDGE;
+
+ /* Bridge specifics */
+ ifacedef->data.bridge.delay =
+ strdup(udev_device_get_sysattr_value(dev, "bridge/forward_delay"));
+ if (!ifacedef->data.bridge.delay) {
+ virReportOOMError();
+ goto cleanup;
+ }
+
+ stp_str = udev_device_get_sysattr_value(dev, "bridge/stp_state");
+ if (virStrToLong_i(stp_str, NULL, 10, &stp) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Could not parse STP state '%s'"), stp_str);
+ goto cleanup;
+ }
+ ifacedef->data.bridge.stp = stp;
+
+ /* Members of the bridge */
+ virAsprintf(&member_path, "%s/%s",
+ udev_device_get_syspath(dev), "brif");
+ if (!member_path) {
+ virReportOOMError();
+ goto cleanup;
+ }
+
+ /* Get each member of the bridge */
+ member_count = scandir(member_path, &member_list,
+ udevIfaceScanDirFilter, alphasort);
+
+ /* Don't need the path anymore */
+ VIR_FREE(member_path);
+
+ if (member_count < 0) {
+ virReportSystemError(errno,
+ _("Could not get members of bridge '%s'"),
+ name);
+ goto cleanup;
+ }
+
+ /* Allocate our list of member devices */
+ if (VIR_ALLOC_N(ifacedef->data.bridge.itf, member_count) < 0) {
+ virReportOOMError();
+ goto cleanup;
+ }
+ ifacedef->data.bridge.nbItf = member_count;
+
+ for (int i= 0; i < member_count; i++) {
+ ifacedef->data.bridge.itf[i] =
+ udevIfaceGetIfaceDef(udev, member_list[i]->d_name);
+ VIR_FREE(member_list[i]);
+ }
+
+ VIR_FREE(member_list);
+
+ } else {
+ /* Set our type to ethernet */
+ ifacedef->type = VIR_INTERFACE_TYPE_ETHERNET;
+ }
+
+ return ifacedef;
+
+cleanup:
+ for (int i = 0; i < member_count; i++) {
+ VIR_FREE(member_list[i]);
+ }
+ VIR_FREE(member_list);
+
+ udevIfaceFreeIfaceDef(ifacedef);
+
+ return NULL;
+}
+
+static char *
+udevIfaceGetXMLDesc(virInterfacePtr ifinfo,
+ unsigned int flags)
+{
+ struct udev_iface_driver *driverState = ifinfo->conn->interfacePrivateData;
+ struct udev *udev = udev_ref(driverState->udev);
+ virInterfaceDef *ifacedef;
+ char *xmlstr = NULL;
+
+ virCheckFlags(VIR_INTERFACE_XML_INACTIVE, NULL);
+
+ /* Recursively build up the interface XML based on the requested
+ * interface name
+ */
+ ifacedef = udevIfaceGetIfaceDef(udev, ifinfo->name);
+
+ /* We've already printed by it happened */
+ if (!ifacedef)
+ goto err;
+
+ /* Convert our interface to XML */
+ xmlstr = virInterfaceDefFormat(ifacedef);
+
+ /* Recursively free our interface structures and free the children too */
+ udevIfaceFreeIfaceDef(ifacedef);
+
+err:
+ /* decrement our udev ptr */
+ udev_unref(udev);
+
+ return xmlstr;
+}
+
static int
udevIfaceIsActive(virInterfacePtr ifinfo)
{
@@ -529,6 +779,7 @@ static virInterfaceDriver udevIfaceDriver = {
.listAllInterfaces = udevIfaceListAllInterfaces, /* 0.10.3 */
.interfaceLookupByName = udevIfaceLookupByName, /* 0.10.3 */
.interfaceLookupByMACString = udevIfaceLookupByMACString, /* 0.10.3 */
+ .interfaceGetXMLDesc = udevIfaceGetXMLDesc, /* 0.10.3 */
.interfaceIsActive = udevIfaceIsActive, /* 0.10.3 */
};
--
1.7.8.6
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