vz: simplify getting strings from vzsdk

SDK does not allocate memory when getting strings thus we
need to call every function that returns string twice.
First to obtain string length, second to obtain string
itself. It is tedious so let's create helper functions
for cases when we know length of the result beforehand
and we are not.

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>

diff --git a/src/vz/vz_sdk.c b/src/vz/vz_sdk.c
index 6131b9db86c68865b3fb3fcb42fdf1542b04b436..01de4f6540da761de88f5bc587a3537f1aec3a40 100644 (file)
--- a/src/vz/vz_sdk.c
+++ b/src/vz/vz_sdk.c
@@ -209,6 +209,38 @@ waitJobHelper(PRL_HANDLE job, unsigned int timeout,
     waitJobHelper(job, JOB_INFINIT_WAIT_TIMEOUT, __FILE__,  \
                   __FUNCTION__, __LINE__)
 
+typedef PRL_RESULT (*prlsdkParamGetterType)(PRL_HANDLE, char*, PRL_UINT32*);
+
+static char*
+prlsdkGetStringParamVar(prlsdkParamGetterType getter, PRL_HANDLE handle)
+{
+    PRL_RESULT pret;
+    PRL_UINT32 buflen = 0;
+    char *str = NULL;
+
+    pret = getter(handle, NULL, &buflen);
+    prlsdkCheckRetGoto(pret, error);
+
+    if (VIR_ALLOC_N(str, buflen) < 0)
+        goto error;
+
+    pret = getter(handle, str, &buflen);
+    prlsdkCheckRetGoto(pret, error);
+
+    return str;
+
+ error:
+    VIR_FREE(str);
+    return NULL;
+}
+
+static PRL_RESULT
+prlsdkGetStringParamBuf(prlsdkParamGetterType getter,
+                        PRL_HANDLE handle, char *buf, size_t size)
+{
+    PRL_UINT32 buflen = size;
+    return getter(handle, buf, &buflen);
+}
 
 int
 prlsdkInit(void)
@@ -351,26 +383,14 @@ prlsdkGetDomainIds(PRL_HANDLE sdkdom,
                    unsigned char *uuid)
 {
     char uuidstr[VIR_UUID_STRING_BUFLEN + 2];
-    PRL_UINT32 len;
     PRL_RESULT pret;
 
-    if (name) {
-        len = 0;
-        *name = NULL;
-        /* get name length */
-        pret = PrlVmCfg_GetName(sdkdom, NULL, &len);
-        prlsdkCheckRetGoto(pret, error);
-
-        if (VIR_ALLOC_N(*name, len) < 0)
-            goto error;
-
-        pret = PrlVmCfg_GetName(sdkdom, *name, &len);
-        prlsdkCheckRetGoto(pret, error);
-    }
+    if (name && !(*name = prlsdkGetStringParamVar(PrlVmCfg_GetName, sdkdom)))
+        goto error;
 
     if (uuid) {
-        len = sizeof(uuidstr);
-        pret = PrlVmCfg_GetUuid(sdkdom, uuidstr, &len);
+        pret = prlsdkGetStringParamBuf(PrlVmCfg_GetUuid,
+                                       sdkdom, uuidstr, sizeof(uuidstr));
         prlsdkCheckRetGoto(pret, error);
 
         if (prlsdkUUIDParse(uuidstr, uuid) < 0) {
@@ -473,7 +493,6 @@ prlsdkGetDiskInfo(vzDriverPtr driver,
                   bool isCt)
 {
     char *buf = NULL;
-    PRL_UINT32 buflen = 0;
     PRL_RESULT pret;
     PRL_UINT32 emulatedType;
     PRL_UINT32 ifType;
@@ -505,15 +524,9 @@ prlsdkGetDiskInfo(vzDriverPtr driver,
         disk->device = VIR_DOMAIN_DISK_DEVICE_DISK;
     }
 
-    pret = PrlVmDev_GetFriendlyName(prldisk, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(buf, buflen) < 0)
+    if (!(buf = prlsdkGetStringParamVar(PrlVmDev_GetFriendlyName, prldisk)))
         goto cleanup;
 
-    pret = PrlVmDev_GetFriendlyName(prldisk, buf, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
     if (virDomainDiskSetSource(disk, buf) < 0)
         goto cleanup;
 
@@ -575,8 +588,6 @@ prlsdkGetFSInfo(PRL_HANDLE prldisk,
                 virDomainFSDefPtr fs)
 {
     char *buf = NULL;
-    PRL_UINT32 buflen = 0;
-    PRL_RESULT pret;
     int ret = -1;
 
     fs->type = VIR_DOMAIN_FS_TYPE_FILE;
@@ -588,27 +599,15 @@ prlsdkGetFSInfo(PRL_HANDLE prldisk,
     fs->readonly = false;
     fs->symlinksResolved = false;
 
-    pret = PrlVmDev_GetImagePath(prldisk, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(buf, buflen) < 0)
+    if (!(buf = prlsdkGetStringParamVar(PrlVmDev_GetImagePath, prldisk)))
         goto cleanup;
 
-    pret = PrlVmDev_GetImagePath(prldisk, buf, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
     fs->src = buf;
     buf = NULL;
 
-    pret = PrlVmDevHd_GetMountPoint(prldisk, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(buf, buflen) < 0)
+    if (!(buf = prlsdkGetStringParamVar(PrlVmDevHd_GetMountPoint, prldisk)))
         goto cleanup;
 
-    pret = PrlVmDevHd_GetMountPoint(prldisk, buf, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
     fs->dst = buf;
     buf = NULL;
 
@@ -722,7 +721,6 @@ static int
 prlsdkGetNetInfo(PRL_HANDLE netAdapter, virDomainNetDefPtr net, bool isCt)
 {
     char macstr[VIR_MAC_STRING_BUFLEN];
-    PRL_UINT32 buflen;
     PRL_UINT32 netAdapterIndex;
     PRL_UINT32 emulatedType;
     PRL_RESULT pret;
@@ -734,15 +732,10 @@ prlsdkGetNetInfo(PRL_HANDLE netAdapter, virDomainNetDefPtr net, bool isCt)
 
     /* use device name, shown by prlctl as target device
      * for identifying network adapter in virDomainDefineXML */
-    pret = PrlVmDevNet_GetHostInterfaceName(netAdapter, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(net->ifname, buflen) < 0)
+    if (!(net->ifname = prlsdkGetStringParamVar(PrlVmDevNet_GetHostInterfaceName,
+                                                netAdapter)))
         goto cleanup;
 
-    pret = PrlVmDevNet_GetHostInterfaceName(netAdapter, net->ifname, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
     pret = PrlVmDev_GetIndex(netAdapter, &netAdapterIndex);
     prlsdkCheckRetGoto(pret, cleanup);
 
@@ -756,8 +749,8 @@ prlsdkGetNetInfo(PRL_HANDLE netAdapter, virDomainNetDefPtr net, bool isCt)
         return 0;
     }
 
-    buflen = ARRAY_CARDINALITY(macstr);
-    pret = PrlVmDevNet_GetMacAddressCanonical(netAdapter, macstr, &buflen);
+    pret = prlsdkGetStringParamBuf(PrlVmDevNet_GetMacAddressCanonical,
+                                   netAdapter, macstr, sizeof(macstr));
     prlsdkCheckRetGoto(pret, cleanup);
 
     if (virMacAddrParse(macstr, &net->mac) < 0)
@@ -771,17 +764,11 @@ prlsdkGetNetInfo(PRL_HANDLE netAdapter, virDomainNetDefPtr net, bool isCt)
                        PARALLELS_DOMAIN_ROUTED_NETWORK_NAME) < 0)
             goto cleanup;
     } else {
-        pret = PrlVmDevNet_GetVirtualNetworkId(netAdapter, NULL, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
-        if (VIR_ALLOC_N(net->data.network.name, buflen) < 0)
+        if (!(net->data.network.name =
+              prlsdkGetStringParamVar(PrlVmDevNet_GetVirtualNetworkId,
+                                      netAdapter)))
             goto cleanup;
 
-        pret = PrlVmDevNet_GetVirtualNetworkId(netAdapter,
-                                               net->data.network.name,
-                                               &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
         /*
          * We use VIR_DOMAIN_NET_TYPE_NETWORK for all network adapters
          * except those whose Virtual Network Id differ from Parallels
@@ -874,7 +861,6 @@ prlsdkGetSerialInfo(PRL_HANDLE serialPort, virDomainChrDefPtr chr)
     PRL_UINT32 serialPortIndex;
     PRL_UINT32 emulatedType;
     char *friendlyName = NULL;
-    PRL_UINT32 buflen;
 
     chr->deviceType = VIR_DOMAIN_CHR_DEVICE_TYPE_SERIAL;
     chr->targetTypeAttr = false;
@@ -885,15 +871,10 @@ prlsdkGetSerialInfo(PRL_HANDLE serialPort, virDomainChrDefPtr chr)
     pret = PrlVmDev_GetEmulatedType(serialPort, &emulatedType);
     prlsdkCheckRetGoto(pret, error);
 
-    pret = PrlVmDev_GetFriendlyName(serialPort, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
-    if (VIR_ALLOC_N(friendlyName, buflen) < 0)
+    if (!(friendlyName = prlsdkGetStringParamVar(PrlVmDev_GetFriendlyName,
+                                                 serialPort)))
         goto error;
 
-    pret = PrlVmDev_GetFriendlyName(serialPort, friendlyName, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
     switch (emulatedType) {
     case PDT_USE_OUTPUT_FILE:
         chr->source.type = VIR_DOMAIN_CHR_TYPE_FILE;
@@ -993,7 +974,6 @@ prlsdkAddVNCInfo(PRL_HANDLE sdkdom, virDomainDefPtr def)
     virDomainGraphicsDefPtr gr = NULL;
     PRL_VM_REMOTE_DISPLAY_MODE vncMode;
     PRL_UINT32 port;
-    PRL_UINT32 buflen = 0;
     PRL_RESULT pret;
 
     pret = PrlVmCfg_GetVNCMode(sdkdom, &vncMode);
@@ -1022,15 +1002,10 @@ prlsdkAddVNCInfo(PRL_HANDLE sdkdom, virDomainDefPtr def)
 
     gr->nListens = 1;
 
-    pret = PrlVmCfg_GetVNCHostName(sdkdom, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
-    if (VIR_ALLOC_N(gr->listens[0].address, buflen) < 0)
+    if (!(gr->listens[0].address = prlsdkGetStringParamVar(PrlVmCfg_GetVNCHostName,
+                                                           sdkdom)))
         goto error;
 
-    pret = PrlVmCfg_GetVNCHostName(sdkdom, gr->listens[0].address, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
     gr->listens[0].type = VIR_DOMAIN_GRAPHICS_LISTEN_TYPE_ADDRESS;
 
     if (VIR_APPEND_ELEMENT(def->graphics, def->ngraphics, gr) < 0)
@@ -1145,7 +1120,6 @@ prlsdkConvertCpuInfo(PRL_HANDLE sdkdom,
                      virDomainDefPtr def)
 {
     char *buf;
-    PRL_UINT32 buflen = 0;
     int hostcpus;
     PRL_UINT32 cpuCount;
     PRL_RESULT pret;
@@ -1167,14 +1141,9 @@ prlsdkConvertCpuInfo(PRL_HANDLE sdkdom,
     if (virDomainDefSetVcpus(def, cpuCount) < 0)
         goto cleanup;
 
-    pret = PrlVmCfg_GetCpuMask(sdkdom, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(buf, buflen) < 0)
+    if (!(buf = prlsdkGetStringParamVar(PrlVmCfg_GetCpuMask, sdkdom)))
         goto cleanup;
 
-    pret = PrlVmCfg_GetCpuMask(sdkdom, buf, &buflen);
-
     if (strlen(buf) == 0) {
         if (!(def->cpumask = virBitmapNew(hostcpus)))
             goto cleanup;
@@ -1334,10 +1303,8 @@ static int
 prlsdkBootOrderCheck(PRL_HANDLE sdkdom, PRL_DEVICE_TYPE sdkType, int sdkIndex,
                      virDomainDefPtr def, int bootIndex)
 {
-    PRL_RESULT pret;
     char *sdkName = NULL;
     const char *bootName;
-    PRL_UINT32 buflen = 0;
     PRL_HANDLE dev = PRL_INVALID_HANDLE;
     virDomainDiskDefPtr disk;
     virDomainDiskDevice device;
@@ -1354,15 +1321,9 @@ prlsdkBootOrderCheck(PRL_HANDLE sdkdom, PRL_DEVICE_TYPE sdkType, int sdkIndex,
     switch (sdkType) {
     case PDE_OPTICAL_DISK:
     case PDE_HARD_DISK:
-        pret = PrlVmDev_GetFriendlyName(dev, sdkName, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
-        if (VIR_ALLOC_N(sdkName, buflen) < 0)
+        if (!(sdkName = prlsdkGetStringParamVar(PrlVmDev_GetFriendlyName, dev)))
             goto cleanup;
 
-        pret = PrlVmDev_GetFriendlyName(dev, sdkName, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
         switch (sdkType) {
         case PDE_OPTICAL_DISK:
             device = VIR_DOMAIN_DISK_DEVICE_CDROM;
@@ -1387,15 +1348,10 @@ prlsdkBootOrderCheck(PRL_HANDLE sdkdom, PRL_DEVICE_TYPE sdkType, int sdkIndex,
 
         break;
     case PDE_GENERIC_NETWORK_ADAPTER:
-        pret = PrlVmDevNet_GetHostInterfaceName(dev, NULL, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
-        if (VIR_ALLOC_N(sdkName, buflen) < 0)
+        if (!(sdkName = prlsdkGetStringParamVar(PrlVmDevNet_GetHostInterfaceName,
+                                                dev)))
             goto cleanup;
 
-        pret = PrlVmDevNet_GetHostInterfaceName(dev, sdkName, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
         if (bootIndex >= def->nnets) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("Can find network boot device for index: %d"),
@@ -1524,7 +1480,6 @@ prlsdkLoadDomain(vzDriverPtr driver, virDomainObjPtr dom)
     VIRTUAL_MACHINE_STATE domainState;
     char *home = NULL;
 
-    PRL_UINT32 buflen = 0;
     PRL_RESULT pret;
     PRL_UINT32 ram;
     PRL_UINT32 envId;
@@ -1580,16 +1535,9 @@ prlsdkLoadDomain(vzDriverPtr driver, virDomainObjPtr dom)
     pret = PrlVmCfg_GetEnvId(sdkdom, &envId);
     prlsdkCheckRetGoto(pret, error);
 
-    buflen = 0;
-    pret = PrlVmCfg_GetHomePath(sdkdom, NULL, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
-    if (VIR_ALLOC_N(home, buflen) < 0)
+    if (!(home = prlsdkGetStringParamVar(PrlVmCfg_GetHomePath, sdkdom)))
         goto error;
 
-    pret = PrlVmCfg_GetHomePath(sdkdom, home, &buflen);
-    prlsdkCheckRetGoto(pret, error);
-
     /* For VMs home is actually /directory/config.pvs */
     if (!IS_CT(def)) {
         /* Get rid of /config.pvs in path string */
@@ -1919,7 +1867,6 @@ prlsdkEventsHandler(PRL_HANDLE prlEvent, PRL_VOID_PTR opaque)
     PRL_HANDLE_TYPE handleType;
     char uuidstr[VIR_UUID_STRING_BUFLEN + 2];
     unsigned char uuid[VIR_UUID_BUFLEN];
-    PRL_UINT32 bufsize = ARRAY_CARDINALITY(uuidstr);
     PRL_EVENT_TYPE prlEventType;
 
     pret = PrlHandle_GetType(prlEvent, &handleType);
@@ -1932,7 +1879,8 @@ prlsdkEventsHandler(PRL_HANDLE prlEvent, PRL_VOID_PTR opaque)
     if (driver == NULL)
         goto cleanup;
 
-    pret = PrlEvent_GetIssuerId(prlEvent, uuidstr, &bufsize);
+    pret = prlsdkGetStringParamBuf(PrlEvent_GetIssuerId,
+                                   prlEvent, uuidstr, sizeof(uuidstr));
     prlsdkCheckRetGoto(pret, cleanup);
 
     pret = PrlEvent_GetType(prlEvent, &prlEventType);
@@ -3147,7 +3095,6 @@ prlsdkFindNetByMAC(PRL_HANDLE sdkdom, virMacAddrPtr mac)
     PRL_UINT32 adaptersCount;
     PRL_UINT32 i;
     PRL_HANDLE adapter = PRL_INVALID_HANDLE;
-    PRL_UINT32 len;
     char adapterMac[PRL_MAC_STRING_BUFNAME];
     char expectedMac[PRL_MAC_STRING_BUFNAME];
 
@@ -3160,12 +3107,11 @@ prlsdkFindNetByMAC(PRL_HANDLE sdkdom, virMacAddrPtr mac)
         pret = PrlVmCfg_GetNetAdapter(sdkdom, i, &adapter);
         prlsdkCheckRetGoto(pret, cleanup);
 
-        len = sizeof(adapterMac);
-        memset(adapterMac, 0, sizeof(adapterMac));
-        pret = PrlVmDevNet_GetMacAddress(adapter, adapterMac, &len);
+        pret = prlsdkGetStringParamBuf(PrlVmDevNet_GetMacAddress,
+                                       adapter, adapterMac, sizeof(adapterMac));
         prlsdkCheckRetGoto(pret, cleanup);
 
-        if (memcmp(adapterMac, expectedMac, PRL_MAC_STRING_BUFNAME) == 0)
+        if (STREQ(adapterMac, expectedMac))
             return adapter;
 
         PrlHandle_Free(adapter);
@@ -3415,7 +3361,6 @@ prlsdkGetDiskIndex(PRL_HANDLE sdkdom, virDomainDiskDefPtr disk)
 {
     int idx = -1;
     char *buf = NULL;
-    PRL_UINT32 buflen = 0;
     PRL_RESULT pret;
     PRL_UINT32 hddCount;
     PRL_UINT32 i;
@@ -3429,16 +3374,9 @@ prlsdkGetDiskIndex(PRL_HANDLE sdkdom, virDomainDiskDefPtr disk)
         pret = PrlVmCfg_GetHardDisk(sdkdom, i, &hdd);
         prlsdkCheckRetGoto(pret, cleanup);
 
-        buflen = 0;
-        pret = PrlVmDev_GetFriendlyName(hdd, 0, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
-        if (VIR_ALLOC_N(buf, buflen) < 0)
+        if (!(buf = prlsdkGetStringParamVar(PrlVmDev_GetFriendlyName, hdd)))
             goto cleanup;
 
-        pret = PrlVmDev_GetFriendlyName(hdd, buf, &buflen);
-        prlsdkCheckRetGoto(pret, cleanup);
-
         if (STRNEQ(disk->src->path, buf)) {
 
             PrlHandle_Free(hdd);
@@ -3901,7 +3839,7 @@ prlsdkDomainHasSnapshots(PRL_HANDLE sdkdom, int* found)
     PRL_HANDLE job;
     PRL_HANDLE result;
     char *snapshotxml = NULL;
-    unsigned int len, paramsCount;
+    unsigned int paramsCount;
     xmlDocPtr xml = NULL;
     xmlXPathContextPtr ctxt = NULL;
 
@@ -3918,16 +3856,11 @@ prlsdkDomainHasSnapshots(PRL_HANDLE sdkdom, int* found)
     if (!paramsCount)
         goto cleanup;
 
-    pret = PrlResult_GetParamAsString(result, 0, &len);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (VIR_ALLOC_N(snapshotxml, len+1) < 0)
+    if (!(snapshotxml = prlsdkGetStringParamVar(PrlResult_GetParamAsString,
+                                                result)))
         goto cleanup;
 
-    pret = PrlResult_GetParamAsString(result, snapshotxml, &len);
-    prlsdkCheckRetGoto(pret, cleanup);
-
-    if (len <= 1) {
+    if (*snapshotxml == '\0') {
         /* The document is empty that means no snapshots */
         *found = 0;
         ret = 0;
@@ -4136,12 +4069,12 @@ prlsdkGetBlockStats(virDomainObjPtr dom, virDomainDiskDefPtr disk, virDomainBloc
     return ret;
 }
 
+
 static PRL_HANDLE
 prlsdkFindNetByPath(virDomainObjPtr dom, const char *path)
 {
     PRL_UINT32 count = 0;
     vzDomObjPtr privdom = dom->privateData;
-    PRL_UINT32 buflen = 0;
     PRL_RESULT pret;
     size_t i;
     char *name = NULL;
@@ -4154,15 +4087,10 @@ prlsdkFindNetByPath(virDomainObjPtr dom, const char *path)
         pret = PrlVmCfg_GetNetAdapter(privdom->sdkdom, i, &net);
         prlsdkCheckRetGoto(pret, error);
 
-        pret = PrlVmDevNet_GetHostInterfaceName(net, NULL, &buflen);
-        prlsdkCheckRetGoto(pret, error);
-
-        if (VIR_ALLOC_N(name, buflen) < 0)
+        if (!(name = prlsdkGetStringParamVar(PrlVmDevNet_GetHostInterfaceName,
+                                             net)))
             goto error;
 
-        pret = PrlVmDevNet_GetHostInterfaceName(net, name, &buflen);
-        prlsdkCheckRetGoto(pret, error);
-
         if (STREQ(name, path))
             break;