On Wed, Feb 20, 2013 at 12:38:38PM -0500, John Ferlan wrote:
Update the code to be more in line with how code looks elsewhere in libvirt. Allow listing of domains, networks, storage pools, and network interfaces.
I like the changes to make the style more in line with the rest of the codebase, however, I really think that this example code should be about a minimal use of the API to list a few domains and that's all, so I'm not in favor of extending it to list other kinds of objects. I think people can find the details of how to do that kind of thing in the API docs. Dave
Update the function prototypes in libvirt.c to include a message about the client needing to free() returned name fields. Fix the all domains example flags values. --- examples/hellolibvirt/hellolibvirt.c | 131 ++++++++++++++++++++++------------- src/libvirt.c | 21 +++--- 2 files changed, 91 insertions(+), 61 deletions(-)
diff --git a/examples/hellolibvirt/hellolibvirt.c b/examples/hellolibvirt/hellolibvirt.c index 234637e..85e5ae6 100644 --- a/examples/hellolibvirt/hellolibvirt.c +++ b/examples/hellolibvirt/hellolibvirt.c @@ -15,7 +15,7 @@ showError(virConnectPtr conn) virErrorPtr err;
err = malloc(sizeof(*err)); - if (NULL == err) { + if (!err) { printf("Could not allocate memory for error data\n"); goto out; } @@ -56,14 +56,14 @@ showHypervisorInfo(virConnectPtr conn) * to fail if, for example, there is no connection to a * hypervisor, so check what it returns. */ hvType = virConnectGetType(conn); - if (NULL == hvType) { + if (!hvType) { ret = 1; printf("Failed to get hypervisor type\n"); showError(conn); goto out; }
- if (0 != virConnectGetVersion(conn, &hvVer)) { + if (virConnectGetVersion(conn, &hvVer) < 0) { ret = 1; printf("Failed to get hypervisor version\n"); showError(conn); @@ -85,73 +85,101 @@ out: return ret; }
+/* Turn off the message in order to compile here + * + * The virConnectListAll*(), vir*IsActive(), vir*GetName(), and vir*Free() + * functions require specific types which aren't possible to provide in + * this tabular manner. + */ +#pragma GCC diagnostic ignored "-Wstrict-prototypes" +typedef struct _objectTable objectTable; +struct _objectTable { + const char *objName; + int (*activeFcn)(virConnectPtr); + int (*inactiveFcn)(virConnectPtr); + int (*allFcn)(); + int (*isActiveFcn)(); + const char *(*nameFcn)(); + int (*freeFcn)(); + unsigned int flags; +}; + +objectTable fcnTable[] = { + {"domains", + virConnectNumOfDomains, virConnectNumOfDefinedDomains, + virConnectListAllDomains, virDomainIsActive, + virDomainGetName, virDomainFree, + VIR_CONNECT_LIST_DOMAINS_ACTIVE | + VIR_CONNECT_LIST_DOMAINS_INACTIVE}, + {"networks", + virConnectNumOfNetworks, virConnectNumOfDefinedNetworks, + virConnectListAllNetworks, virNetworkIsActive, + virNetworkGetName, virNetworkFree, + VIR_CONNECT_LIST_NETWORKS_ACTIVE | + VIR_CONNECT_LIST_NETWORKS_INACTIVE}, + {"storage pools", + virConnectNumOfStoragePools, virConnectNumOfDefinedStoragePools, + virConnectListAllStoragePools, virStoragePoolIsActive, + virStoragePoolGetName, virStoragePoolFree, + VIR_CONNECT_LIST_STORAGE_POOLS_ACTIVE | + VIR_CONNECT_LIST_STORAGE_POOLS_INACTIVE}, + {"interfaces", + virConnectNumOfInterfaces, virConnectNumOfDefinedInterfaces, + virConnectListAllInterfaces, virInterfaceIsActive, + virInterfaceGetName, virInterfaceFree, + VIR_CONNECT_LIST_INTERFACES_ACTIVE | + VIR_CONNECT_LIST_INTERFACES_INACTIVE}, + {NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0} +};
static int -showDomains(virConnectPtr conn) +showObject(virConnectPtr conn, objectTable entry) { - int ret = 0, i, numNames, numInactiveDomains, numActiveDomains; - char **nameList = NULL; + int ret = 0, numActive, numInactive, numObjects, i; + void **objects = NULL;
- numActiveDomains = virConnectNumOfDomains(conn); - if (-1 == numActiveDomains) { + if ((numActive = (*entry.activeFcn)(conn)) < 0) { ret = 1; - printf("Failed to get number of active domains\n"); + printf("Failed to get number of active %s\n", entry.objName); showError(conn); goto out; }
- numInactiveDomains = virConnectNumOfDefinedDomains(conn); - if (-1 == numInactiveDomains) { + if ((numInactive = (*entry.inactiveFcn)(conn)) < 0) { ret = 1; - printf("Failed to get number of inactive domains\n"); + printf("Failed to get number of inactive %s\n", entry.objName); showError(conn); goto out; }
- printf("There are %d active and %d inactive domains\n", - numActiveDomains, numInactiveDomains); + printf("There are %d active and %d inactive %s:\n", + numActive, numInactive, entry.objName);
- nameList = malloc(sizeof(*nameList) * numInactiveDomains); - - if (NULL == nameList) { + if ((numObjects = (*entry.allFcn)(conn, &objects, entry.flags)) < 0) { ret = 1; - printf("Could not allocate memory for list of inactive domains\n"); - goto out; - } - - numNames = virConnectListDefinedDomains(conn, - nameList, - numInactiveDomains); - - if (-1 == numNames) { - ret = 1; - printf("Could not get list of defined domains from hypervisor\n"); + printf("Failed to get all %s\n", entry.objName); showError(conn); goto out; } - - if (numNames > 0) { - printf("Inactive domains:\n"); - } - - for (i = 0 ; i < numNames ; i++) { - printf(" %s\n", *(nameList + i)); - /* The API documentation doesn't say so, but the names - * returned by virConnectListDefinedDomains are strdup'd and - * must be freed here. */ - free(*(nameList + i)); + for (i = 0; i < numObjects; i++) { + int active = (*entry.isActiveFcn)(objects[i]); + /* Sure the name could be longer, but for a quick example this works */ + printf("\t%8s (%s)\n", + (*entry.nameFcn)(objects[i]), + (active == 1 ? "active" : "non-active")); + + /* We have to free the entry */ + (*entry.freeFcn)(objects[i]); } - + free(objects); out: - free(nameList); return ret; }
- int main(int argc, char *argv[]) { - int ret = 0; + int ret = 0, i; virConnectPtr conn; char *uri;
@@ -163,7 +191,7 @@ main(int argc, char *argv[]) * except, possibly, the URI of the hypervisor. */ conn = virConnectOpenAuth(uri, virConnectAuthPtrDefault, 0);
- if (NULL == conn) { + if (!conn) { ret = 1; printf("No connection to hypervisor\n"); showError(conn); @@ -171,7 +199,7 @@ main(int argc, char *argv[]) }
uri = virConnectGetURI(conn); - if (NULL == uri) { + if (!uri) { ret = 1; printf("Failed to get URI for hypervisor connection\n"); showError(conn); @@ -181,18 +209,21 @@ main(int argc, char *argv[]) printf("Connected to hypervisor at \"%s\"\n", uri); free(uri);
- if (0 != showHypervisorInfo(conn)) { + if (showHypervisorInfo(conn) < 0) { ret = 1; goto disconnect; }
- if (0 != showDomains(conn)) { - ret = 1; - goto disconnect; + i = 0; + while (fcnTable[i].objName) { + ret = showObject(conn, fcnTable[i]); + if (ret != 0) + goto disconnect; + i++; }
disconnect: - if (0 != virConnectClose(conn)) { + if (virConnectClose(conn) < 0) { printf("Failed to disconnect from hypervisor\n"); showError(conn); ret = 1; diff --git a/src/libvirt.c b/src/libvirt.c index 1e78500..e717f16 100644 --- a/src/libvirt.c +++ b/src/libvirt.c @@ -8304,19 +8304,18 @@ error: * VIR_CONNECT_LIST_DOMAINS_NO_SNAPSHOT, for filtering based on whether * a domain has snapshots. * - * Returns the number of domains found or -1 and sets domains to NULL in case - * of error. On success, the array stored into @doms is guaranteed to have an + * Returns the number of domains found or -1 and sets domains to NULL in case of + * error. On success, the array stored into @domains is guaranteed to have an * extra allocated element set to NULL but not included in the return count, to * make iteration easier. The caller is responsible for calling virDomainFree() - * on each array element, then calling free() on @doms. + * on each array element, then calling free() on @domains. * * Example of usage: * virDomainPtr *domains; - * virDomainPtr dom; * int i; * int ret; - * unsigned int flags = VIR_CONNECT_LIST_RUNNING | - * VIR_CONNECT_LIST_PERSISTENT; + * unsigned int flags = VIR_CONNECT_LIST_DOMAINS_RUNNING | + * VIR_CONNECT_LIST_DOMAINS_PERSISTENT; * * ret = virConnectListAllDomains(conn, &domains, flags); * if (ret < 0) @@ -10226,7 +10225,7 @@ error: * this command is inherently racy; a network can be started between a call * to virConnectNumOfNetworks() and this call; you are only guaranteed that * all currently active networks were listed if the return is less than - * @maxnames. + * @maxnames. The client must call free() on each returned name. */ int virConnectListNetworks(virConnectPtr conn, char **const names, int maxnames) @@ -11208,7 +11207,7 @@ error: * this command is inherently racy; a interface can be started between a call * to virConnectNumOfInterfaces() and this call; you are only guaranteed that * all currently active interfaces were listed if the return is less than - * @maxnames. + * @maxnames. The client must call free() on each returned name. */ int virConnectListInterfaces(virConnectPtr conn, char **const names, int maxnames) @@ -12076,7 +12075,7 @@ error: * this command is inherently racy; a pool can be started between a call to * virConnectNumOfStoragePools() and this call; you are only guaranteed * that all currently active pools were listed if the return is less than - * @maxnames. + * @maxnames. The client must call free() on each returned name. */ int virConnectListStoragePools(virConnectPtr conn, @@ -18285,7 +18284,7 @@ error: * the results, see virDomainListAllSnapshots(). * * Returns the number of domain snapshots found or -1 in case of error. - * The caller is responsible for freeing each member of the array. + * The caller is responsible to call free() for each member of the array. */ int virDomainSnapshotListNames(virDomainPtr domain, char **names, int nameslen, @@ -18534,7 +18533,7 @@ error: * the results, see virDomainSnapshotListAllChildren(). * * Returns the number of domain snapshots found or -1 in case of error. - * The caller is responsible for freeing each member of the array. + * The caller is responsible to call free() for each member of the array. */ int virDomainSnapshotListChildrenNames(virDomainSnapshotPtr snapshot, -- 1.7.11.7
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