[libvirt] [PATCHv7 1/4] domifaddr: Implement the public APIs
Nehal J Wani
nehaljw.kkd1 at gmail.com
Wed Dec 17 00:16:20 UTC 2014
Define helper function virDomainInterfaceFree, which allows
the upper layer application to free the domain interface object
conveniently.
The API is going to provide multiple methods by flags, e.g.
* Query guest agent
* Parse DHCP lease file
include/libvirt/libvirt-domain.h
* Define virDomainInterfaceAddresses, virDomainInterfaceFree
* Define structs virDomainInterface, virDomainIPAddress
src/driver-hypervisor.h:
* Define domainInterfaceAddresses
src/libvirt-domain.c:
* Implement virDomainInterfaceAddresses
* Implement virDomainInterfaceFree
src/libvirt_public.syms:
* Export the new symbols
Signed-off-by: Nehal J Wani <nehaljw.kkd1 at gmail.com>
---
include/libvirt/libvirt-domain.h | 27 ++++++++
src/driver-hypervisor.h | 5 ++
src/libvirt-domain.c | 129 ++++++++++++++++++++++++++++++++++++++
src/libvirt_public.syms | 2 +
4 files changed, 163 insertions(+)
diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index ae2c49c..57a9d7f 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -3665,5 +3665,32 @@ typedef struct _virTypedParameter virMemoryParameter;
*/
typedef virMemoryParameter *virMemoryParameterPtr;
+typedef enum {
+ VIR_DOMAIN_INTERFACE_ADDRESSES_LEASE = (1 << 0), /* Parse DHCP lease file */
+ VIR_DOMAIN_INTERFACE_ADDRESSES_AGENT = (1 << 1), /* Query qemu guest agent */
+} virDomainInterfaceAddressesFlags;
+
+typedef struct _virDomainInterfaceIPAddress virDomainIPAddress;
+typedef virDomainIPAddress *virDomainIPAddressPtr;
+struct _virDomainInterfaceIPAddress {
+ int type; /* virIPAddrType */
+ char *addr; /* IP address */
+ unsigned int prefix; /* IP address prefix */
+};
+
+typedef struct _virDomainInterface virDomainInterface;
+typedef virDomainInterface *virDomainInterfacePtr;
+struct _virDomainInterface {
+ char *name; /* interface name */
+ char *hwaddr; /* hardware address */
+ unsigned int naddrs; /* number of items in @addrs */
+ virDomainIPAddressPtr addrs; /* array of IP addresses */
+};
+
+int virDomainInterfaceAddresses(virDomainPtr dom,
+ virDomainInterfacePtr **ifaces,
+ unsigned int flags);
+
+void virDomainInterfaceFree(virDomainInterfacePtr iface);
#endif /* __VIR_LIBVIRT_DOMAIN_H__ */
diff --git a/src/driver-hypervisor.h b/src/driver-hypervisor.h
index 9f26b13..b2485a1 100644
--- a/src/driver-hypervisor.h
+++ b/src/driver-hypervisor.h
@@ -1170,6 +1170,10 @@ typedef int
unsigned int cellCount,
unsigned int flags);
+typedef int
+(*virDrvDomainInterfaceAddresses)(virDomainPtr dom,
+ virDomainInterfacePtr **ifaces,
+ unsigned int flags);
typedef struct _virHypervisorDriver virHypervisorDriver;
typedef virHypervisorDriver *virHypervisorDriverPtr;
@@ -1396,6 +1400,7 @@ struct _virHypervisorDriver {
virDrvConnectGetAllDomainStats connectGetAllDomainStats;
virDrvNodeAllocPages nodeAllocPages;
virDrvDomainGetFSInfo domainGetFSInfo;
+ virDrvDomainInterfaceAddresses domainInterfaceAddresses;
};
diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index cb76d8c..d94cf0a 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -11192,3 +11192,132 @@ virDomainFSInfoFree(virDomainFSInfoPtr info)
VIR_FREE(info->devAlias[i]);
VIR_FREE(info->devAlias);
}
+
+/**
+ * virDomainInterfaceAddresses:
+ * @dom: domain object
+ * @ifaces: pointer to an array of pointers pointing to interface objects
+ * @flags: bitwise-OR of virDomainInterfaceAddressesFlags
+ *
+ * Return a pointer to the allocated array of pointers pointing to interfaces
+ * present in given domain along with their IP and MAC addresses. Note that
+ * single interface can have multiple or even 0 IP address.
+ *
+ * This API dynamically allocates the virDomainInterfacePtr struct based on
+ * how many interfaces domain @dom has, usually there's 1:1 correlation. The
+ * count of the interfaces is returned as the return value.
+ *
+ * In case @flags includes VIR_DOMAIN_INTERFACE_ADDRESSES_AGENT, a configured
+ * guest agent is needed for successful return from this API. Moreover, if
+ * guest agent is used then the interface name is the one seen by guest OS.
+ * To match such interface with the one from @dom XML use MAC address or IP
+ * range.
+ *
+ * The lease-file parsing method returns the interface name of the form "vnetN",
+ * which is different from what guest agent returns (like ethN or emN), and
+ * since the MAC address from guest agent might be different with what @dom XML
+ * specifies, we have no way to convert it into the names present in @dom
+ * config. Hence, it is not recommended to mix the flag ..._AGENT with
+ * ..._LEASE as it may lead to ambiguous results because we cannot be sure if
+ * the name came from the agent or from the other method.
+ *
+ * If 0 is passed as @flags, libvirt will choose the best way, and won't
+ * include agent in it.
+ *
+ * @ifaces->name and @ifaces->hwaddr are never NULL.
+ *
+ * The caller *must* free @ifaces when no longer needed. Usual use case
+ * looks like this:
+ *
+ * virDomainInterfacePtr *ifaces = NULL;
+ * int ifaces_count = 0;
+ * size_t i, j;
+ * virDomainPtr dom = ... obtain a domain here ...;
+ *
+ * if ((ifaces_count = virDomainInterfaceAddresses(dom, &ifaces, 0)) < 0)
+ * goto cleanup;
+ *
+ * ... do something with returned values, for example:
+ * for (i = 0; i < ifaces_count; i++) {
+ * printf("name: %s", ifaces[i]->name);
+ * if (ifaces[i]->hwaddr)
+ * printf(" hwaddr: %s", ifaces[i]->hwaddr);
+ *
+ * for (j = 0; j < ifaces[i]->naddrs; j++) {
+ * virDomainIPAddressPtr ip_addr = ifaces[i]->addrs + j;
+ * printf("[addr: %s prefix: %d type: %d]",
+ * ip_addr->addr, ip_addr->prefix, ip_addr->type);
+ * }
+ * printf("\n");
+ * }
+ *
+ * cleanup:
+ * if (ifaces)
+ * for (i = 0; i < ifaces_count; i++)
+ * virDomainInterfaceFree(ifaces[i]);
+ * free(ifaces);
+ *
+ * Returns the number of interfaces on success, -1 in case of error.
+ */
+int
+virDomainInterfaceAddresses(virDomainPtr dom,
+ virDomainInterfacePtr **ifaces,
+ unsigned int flags)
+{
+ virConnectPtr conn;
+
+ VIR_DOMAIN_DEBUG(dom, "ifaces=%p, flags=%x", ifaces, flags);
+
+ virResetLastError();
+
+ conn = dom->conn;
+
+ virCheckNonNullArgGoto(ifaces, error);
+
+ if ((flags & VIR_DOMAIN_INTERFACE_ADDRESSES_AGENT)
+ && (conn->flags & VIR_CONNECT_RO)) {
+ virReportError(VIR_ERR_OPERATION_DENIED, "%s",
+ _("Cannot query guest agent in readonly mode"));
+ goto error;
+ }
+
+ if (conn->driver->domainInterfaceAddresses) {
+ int ret;
+ ret = conn->driver->domainInterfaceAddresses(dom, ifaces, flags);
+ if (ret < 0)
+ goto error;
+ return ret;
+ }
+
+ virReportError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+ error:
+ virDispatchError(dom->conn);
+ return -1;
+}
+
+
+/**
+ * virDomainInterfaceFree:
+ * @iface: an interface object
+ *
+ * Free the interface object. The data structure is
+ * freed and should not be used thereafter.
+ */
+void
+virDomainInterfaceFree(virDomainInterfacePtr iface)
+{
+ size_t i;
+
+ if (!iface)
+ return;
+
+ VIR_FREE(iface->name);
+ VIR_FREE(iface->hwaddr);
+
+ for (i = 0; i < iface->naddrs; i++)
+ VIR_FREE(iface->addrs[i].addr);
+ VIR_FREE(iface->addrs);
+
+ VIR_FREE(iface);
+}
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index e4c2df1..395017e 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -688,6 +688,8 @@ LIBVIRT_1.2.11 {
global:
virDomainFSInfoFree;
virDomainGetFSInfo;
+ virDomainInterfaceAddresses;
+ virDomainInterfaceFree;
} LIBVIRT_1.2.9;
# .... define new API here using predicted next version number ....
--
1.7.10.4
More information about the libvir-list
mailing list