[libvirt] [PATCH 1/2] driver: Include source parameter to virDomainGetHostname

jcfaracco at gmail.com jcfaracco at gmail.com
Sun Nov 24 20:19:48 UTC 2019


From: Julio Faracco <jcfaracco at gmail.com>

There is a lots of possibilities to retrieve hostname information from
domain. Libvirt could use lease information from dnsmasq to get current
hostname too. QEMU supports QEMU-agent but it can use lease source. See
'domifaddr' as an example.

This commit still adds lease options for QEMU. It will get the first
hostname available from domain networks.

Signed-off-by: Julio Faracco <jcfaracco at gmail.com>
---
 include/libvirt/libvirt-domain.h | 10 +++++
 src/driver-hypervisor.h          |  1 +
 src/libvirt-domain.c             |  7 +++-
 src/openvz/openvz_driver.c       | 30 +++++++++-----
 src/qemu/qemu_driver.c           | 67 +++++++++++++++++++++++++++-----
 src/remote/remote_protocol.x     |  1 +
 src/remote_protocol-structs      |  1 +
 src/test/test_driver.c           |  1 +
 tools/virsh-domain.c             | 25 +++++++++++-
 9 files changed, 120 insertions(+), 23 deletions(-)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index a2f007568c..cc3d6ed0ca 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -1554,6 +1554,7 @@ int                     virDomainGetMaxVcpus    (virDomainPtr domain);
 int                     virDomainGetSecurityLabel (virDomainPtr domain,
                                                    virSecurityLabelPtr seclabel);
 char *                  virDomainGetHostname    (virDomainPtr domain,
+                                                 unsigned int source,
                                                  unsigned int flags);
 int                     virDomainGetSecurityLabelList (virDomainPtr domain,
                                                        virSecurityLabelPtr* seclabels);
@@ -4790,6 +4791,15 @@ typedef struct _virTypedParameter virMemoryParameter;
  */
 typedef virMemoryParameter *virMemoryParameterPtr;
 
+typedef enum {
+    VIR_DOMAIN_HOSTNAME_SRC_LEASE = 0, /* Parse DHCP lease file */
+    VIR_DOMAIN_HOSTNAME_SRC_AGENT = 1, /* Query qemu guest agent */
+
+# ifdef VIR_ENUM_SENTINELS
+    VIR_DOMAIN_HOSTNAME_SRC_LAST
+# endif
+} virDomainHostnameSource;
+
 typedef enum {
     VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LEASE = 0, /* Parse DHCP lease file */
     VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_AGENT = 1, /* Query qemu guest agent */
diff --git a/src/driver-hypervisor.h b/src/driver-hypervisor.h
index 4afd8f6ec5..6338a3ab73 100644
--- a/src/driver-hypervisor.h
+++ b/src/driver-hypervisor.h
@@ -156,6 +156,7 @@ typedef char *
 
 typedef char *
 (*virDrvDomainGetHostname)(virDomainPtr domain,
+                           unsigned int source,
                            unsigned int flags);
 
 typedef unsigned long long
diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index 51fb79cddd..6aa093d8af 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -11017,6 +11017,7 @@ virDomainGetDiskErrors(virDomainPtr dom,
 /**
  * virDomainGetHostname:
  * @domain: a domain object
+ * @source: one of the virDomainHostnameSource constants
  * @flags: extra flags; not used yet, so callers should always pass 0
  *
  * Get the hostname for that domain.
@@ -11028,7 +11029,9 @@ virDomainGetDiskErrors(virDomainPtr dom,
  * NULL if there was an error.
  */
 char *
-virDomainGetHostname(virDomainPtr domain, unsigned int flags)
+virDomainGetHostname(virDomainPtr domain,
+                     unsigned int source,
+                     unsigned int flags)
 {
     virConnectPtr conn;
 
@@ -11043,7 +11046,7 @@ virDomainGetHostname(virDomainPtr domain, unsigned int flags)
 
     if (conn->driver->domainGetHostname) {
         char *ret;
-        ret = conn->driver->domainGetHostname(domain, flags);
+        ret = conn->driver->domainGetHostname(domain, source, flags);
         if (!ret)
             goto error;
         return ret;
diff --git a/src/openvz/openvz_driver.c b/src/openvz/openvz_driver.c
index e07b3b302d..363eb5522a 100644
--- a/src/openvz/openvz_driver.c
+++ b/src/openvz/openvz_driver.c
@@ -295,7 +295,9 @@ openvzSetDiskQuota(virDomainDefPtr vmdef,
 
 
 static char *
-openvzDomainGetHostname(virDomainPtr dom, unsigned int flags)
+openvzDomainGetHostname(virDomainPtr dom,
+                        unsigned int source,
+                        unsigned int flags)
 {
     char *hostname = NULL;
     struct openvz_driver *driver = dom->conn->privateData;
@@ -305,15 +307,25 @@ openvzDomainGetHostname(virDomainPtr dom, unsigned int flags)
     if (!(vm = openvzDomObjFromDomain(driver, dom->uuid)))
         return NULL;
 
-    hostname = openvzVEGetStringParam(dom, "hostname");
-    if (hostname == NULL)
-        goto cleanup;
+    switch (source) {
+    default:
+        hostname = openvzVEGetStringParam(dom, "hostname");
+        if (hostname == NULL)
+            goto cleanup;
 
-    /* vzlist prints an unset hostname as '-' */
-    if (STREQ(hostname, "-")) {
-        virReportError(VIR_ERR_OPERATION_FAILED,
-                       _("Hostname of '%s' is unset"), vm->def->name);
-        VIR_FREE(hostname);
+        /* vzlist prints an unset hostname as '-' */
+        if (STREQ(hostname, "-")) {
+            virReportError(VIR_ERR_OPERATION_FAILED,
+                           _("Hostname of '%s' is unset"), vm->def->name);
+            VIR_FREE(hostname);
+        }
+        break;
+    case VIR_DOMAIN_HOSTNAME_SRC_AGENT:
+    case VIR_DOMAIN_HOSTNAME_SRC_LEASE:
+        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
+                       _("Unknown hostname data source %d"),
+                       source);
+        break;
     }
 
  cleanup:
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 669c12d6ca..afcd5e8571 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -20085,11 +20085,17 @@ qemuConnectGetCPUModelNames(virConnectPtr conn,
 
 static char *
 qemuDomainGetHostname(virDomainPtr dom,
+                      unsigned int source,
                       unsigned int flags)
 {
     virQEMUDriverPtr driver = dom->conn->privateData;
     virDomainObjPtr vm = NULL;
     qemuAgentPtr agent;
+    char macaddr[VIR_MAC_STRING_BUFLEN];
+    g_autoptr(virNetwork) network = NULL;
+    virNetworkDHCPLeasePtr *leases = NULL;
+    int n_leases;
+    size_t i, j;
     char *hostname = NULL;
 
     virCheckFlags(0, NULL);
@@ -20100,21 +20106,62 @@ qemuDomainGetHostname(virDomainPtr dom,
     if (virDomainGetHostnameEnsureACL(dom->conn, vm->def) < 0)
         goto cleanup;
 
-    if (qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_QUERY) < 0)
-        goto cleanup;
-
     if (virDomainObjCheckActive(vm) < 0)
         goto endjob;
 
-    if (!qemuDomainAgentAvailable(vm, true))
-        goto endjob;
+    switch (source) {
+    default:
+    case VIR_DOMAIN_HOSTNAME_SRC_AGENT:
+        if (qemuDomainObjBeginAgentJob(driver, vm, QEMU_AGENT_JOB_QUERY) < 0)
+            goto cleanup;
 
-    agent = qemuDomainObjEnterAgent(vm);
-    ignore_value(qemuAgentGetHostname(agent, &hostname));
-    qemuDomainObjExitAgent(vm, agent);
+        if (!qemuDomainAgentAvailable(vm, true))
+            goto endjob;
 
- endjob:
-    qemuDomainObjEndAgentJob(vm);
+        agent = qemuDomainObjEnterAgent(vm);
+        ignore_value(qemuAgentGetHostname(agent, &hostname));
+        qemuDomainObjExitAgent(vm, agent);
+
+     endjob:
+        qemuDomainObjEndAgentJob(vm);
+        break;
+    case VIR_DOMAIN_HOSTNAME_SRC_LEASE:
+        for (i = 0; i < vm->def->nnets; i++) {
+            if (vm->def->nets[i]->type != VIR_DOMAIN_NET_TYPE_NETWORK)
+                continue;
+
+            virMacAddrFormat(&(vm->def->nets[i]->mac), macaddr);
+            virObjectUnref(network);
+            network = virNetworkLookupByName(dom->conn,
+                                             vm->def->nets[i]->data.network.name);
+
+            if ((n_leases = virNetworkGetDHCPLeases(network, macaddr,
+                                                    &leases, 0)) < 0)
+                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                               _("There is no available hostname %d"),
+                               source);
+
+            for (j = 0; j < n_leases; j++) {
+                virNetworkDHCPLeasePtr lease = leases[j];
+                if (lease->hostname) {
+                    hostname = g_strdup(lease->hostname);
+
+                    for (j = 0; j < n_leases; j++)
+                        virNetworkDHCPLeaseFree(leases[j]);
+
+                    VIR_FREE(leases);
+
+                    goto cleanup;
+                }
+            }
+
+            for (j = 0; j < n_leases; j++)
+                virNetworkDHCPLeaseFree(leases[j]);
+
+            VIR_FREE(leases);
+        }
+        break;
+    }
 
  cleanup:
     virDomainObjEndAPI(&vm);
diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
index 23e42d17b1..8d09f605da 100644
--- a/src/remote/remote_protocol.x
+++ b/src/remote/remote_protocol.x
@@ -1467,6 +1467,7 @@ struct remote_domain_get_cpu_stats_ret {
 
 struct remote_domain_get_hostname_args {
     remote_nonnull_domain dom;
+    unsigned int source;
     unsigned int flags;
 };
 
diff --git a/src/remote_protocol-structs b/src/remote_protocol-structs
index 9ad7a857e0..dd9d1ec6fa 100644
--- a/src/remote_protocol-structs
+++ b/src/remote_protocol-structs
@@ -3543,4 +3543,5 @@ enum remote_procedure {
         REMOTE_PROC_DOMAIN_GET_GUEST_INFO = 418,
         REMOTE_PROC_CONNECT_SET_IDENTITY = 419,
         REMOTE_PROC_DOMAIN_AGENT_SET_RESPONSE_TIMEOUT = 420,
+        REMOTE_PROC_DOMAIN_GET_HOSTNAME = 421,
 };
diff --git a/src/test/test_driver.c b/src/test/test_driver.c
index 5883722d60..0cbda81c67 100644
--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
@@ -2028,6 +2028,7 @@ testDomainReset(virDomainPtr dom,
 
 static char *
 testDomainGetHostname(virDomainPtr domain,
+                      unsigned int source G_GNUC_UNUSED,
                       unsigned int flags)
 {
     char *ret = NULL;
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 6be9780836..141b141a10 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -11669,6 +11669,10 @@ static const vshCmdInfo info_domhostname[] = {
 
 static const vshCmdOptDef opts_domhostname[] = {
     VIRSH_COMMON_OPT_DOMAIN_FULL(VIR_CONNECT_LIST_DOMAINS_ACTIVE),
+    {.name = "source",
+     .type = VSH_OT_STRING,
+     .flags = VSH_OFLAG_NONE,
+     .help = N_("address source: 'lease' or 'agent'")},
     {.name = NULL}
 };
 
@@ -11678,21 +11682,38 @@ cmdDomHostname(vshControl *ctl, const vshCmd *cmd)
     char *hostname;
     virDomainPtr dom;
     bool ret = false;
+    const char *sourcestr = NULL;
+    int source = -1; /* Use default value. Drivers can have its own default. */
 
     if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
         return false;
 
-    hostname = virDomainGetHostname(dom, 0);
+    if (vshCommandOptStringReq(ctl, cmd, "source", &sourcestr) < 0)
+        goto error;
+
+    if (sourcestr) {
+        if (STREQ(sourcestr, "lease")) {
+            source = VIR_DOMAIN_HOSTNAME_SRC_LEASE;
+        } else if (STREQ(sourcestr, "agent")) {
+            source = VIR_DOMAIN_HOSTNAME_SRC_AGENT;
+        } else {
+            vshError(ctl, _("Unknown data source '%s'"), sourcestr);
+            goto error;
+        }
+    }
+
+    hostname = virDomainGetHostname(dom, source, 0);
     if (hostname == NULL) {
         vshError(ctl, "%s", _("failed to get hostname"));
         goto error;
     }
 
     vshPrint(ctl, "%s\n", hostname);
+
+    VIR_FREE(hostname);
     ret = true;
 
  error:
-    VIR_FREE(hostname);
     virshDomainFree(dom);
     return ret;
 }
-- 
2.20.1





More information about the libvir-list mailing list