Re: [libvirt] [PATCH 1/2] network: backend for virNetworkUpdate of dhcp range

The dhcp range element is contained in the <dhcp> element of one of a network's <ip> elements. There can be multiple <range> elements. Because there are only two attributes (start and end), and those are exactly what you would use to identify a particular range, it doesn't really make sense to modify an existing element, so VIR_NETWORK_UPDATE_COMMAND_MODIFY isn't supported for this section, only ADD_FIRST, ADD_LAST, and DELETE. Since virsh already has support for understanding all the defined sections, this new backend is automatically supported by virsh. You would use it like this: virsh net-update mynet add ip-dhcp-range \ "<range start='1.2.3.4' end='1.2.3.20'/>" --live --config The bridge driver also already supports all sections, so it's doing the correct thing in this case as well - since the dhcp range is placed on the dnsmasq commandline, the bridge driver recreates the dnsmasq commandline, and re-runs dnsmasq whenever a range is added/deleted (and AFFECT_LIVE is specified in the flags). --- src/conf/network_conf.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 88 insertions(+), 4 deletions(-) diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c index f33834f..7fc559f 100644 --- a/src/conf/network_conf.c +++ b/src/conf/network_conf.c @@ -2494,14 +2494,98 @@ cleanup: static int virNetworkDefUpdateIPDHCPRange(virNetworkDefPtr def, - unsigned int command ATTRIBUTE_UNUSED, + unsigned int command, int parentIndex ATTRIBUTE_UNUSED, - xmlXPathContextPtr ctxt ATTRIBUTE_UNUSED, + xmlXPathContextPtr ctxt, /* virNetworkUpdateFlags */ unsigned int fflags ATTRIBUTE_UNUSED) { - virNetworkDefUpdateNoSupport(def, "ip dhcp range"); - return -1; + int ii, ret = -1; + virNetworkIpDefPtr ipdef = virNetworkIpDefByIndex(def, parentIndex); + virNetworkDHCPRangeDef range; + + memset(&range, 0, sizeof(range)); + + if (virNetworkDefUpdateCheckElementName(def, ctxt->node, "range") < 0) + goto cleanup; + + /* ipdef is the ip element that needs its range array updated */ + if (!ipdef) + goto cleanup; + + /* parse the xml into a virNetworkDHCPRangeDef */ + if (command == VIR_NETWORK_UPDATE_COMMAND_MODIFY) { + + virReportError(VIR_ERR_NO_SUPPORT, "%s", + _("dhcp ranges cannot be modified, " + "only added or deleted")); + goto cleanup; + } + + if (virNetworkDHCPRangeDefParse(def->name, ctxt->node, &range) < 0) + goto cleanup; + + /* check if an entry with same name/address/ip already exists */ + for (ii = 0; ii < ipdef->nranges; ii++) { + if (virSocketAddrEqual(&range.start, &ipdef->ranges[ii].start) && + virSocketAddrEqual(&range.end, &ipdef->ranges[ii].end)) { + break; + } + } + + if ((command == VIR_NETWORK_UPDATE_COMMAND_ADD_FIRST) || + (command == VIR_NETWORK_UPDATE_COMMAND_ADD_LAST)) { + + if (ii < ipdef->nranges) { + char *startip = virSocketAddrFormat(&range.start); + char *endip = virSocketAddrFormat(&range.end); + + virReportError(VIR_ERR_OPERATION_INVALID, + _("there is an existing dhcp range entry in " + "network '%s' that matches " + "\"<range start='%s' end='%s'/>\""), + def->name, + startip ? startip : "unknown", + endip ? endip : "unknown"); + goto cleanup; + } + + /* add to beginning/end of list */ + if (VIR_REALLOC_N(ipdef->ranges, ipdef->nranges +1) < 0) { + virReportOOMError(); + goto cleanup; + } + + if (command == VIR_NETWORK_UPDATE_COMMAND_ADD_LAST) { + ipdef->ranges[ipdef->nranges] = range; + } else { /* implied (command == VIR_NETWORK_UPDATE_COMMAND_ADD_FIRST) */ + memmove(ipdef->ranges + 1, ipdef->ranges, + sizeof(*ipdef->ranges) * ipdef->nranges); + ipdef->ranges[0] = range; + } + ipdef->nranges++; + memset(&range, 0, sizeof(range)); + + } else if (command == VIR_NETWORK_UPDATE_COMMAND_DELETE) { + + if (ii == ipdef->nranges) { + virReportError(VIR_ERR_OPERATION_INVALID, + _("couldn't locate a matching dhcp range entry " + "in network '%s'"), def->name); + goto cleanup; + } + + /* remove it */ + /* NB: nothing to clear from a RangeDef that's being freed */ + memmove(ipdef->ranges + ii, ipdef->ranges + ii + 1, + sizeof(*ipdef->ranges) * (ipdef->nranges - ii - 1)); + ipdef->nranges--; + ignore_value(VIR_REALLOC_N(ipdef->ranges, ipdef->nranges)); + } + + ret = 0; +cleanup: + return ret; } static int