Operational Discovery with Continuous Query Support for Linux (#33402)
* Add operational discovery and continuous query support in linux platform mdns
* Restyled by whitespace
* Restyled by clang-format
* Updated as per feedback comments
* Updated as per review feedback
* Restyled by whitespace
* Restyled by clang-format
* Updated as per review feedback
* Updated as per new review feedback
* Restyled by whitespace
* Restyled by clang-format
* Updated as per new review feedback and fixed builds
* Updated as per suggestions
* Fix comment spelling.
---------
Co-authored-by: Restyled.io <commits@restyled.io>
Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>
diff --git a/src/lib/dnssd/Discovery_ImplPlatform.cpp b/src/lib/dnssd/Discovery_ImplPlatform.cpp
index f4a524f..a1b28b7 100644
--- a/src/lib/dnssd/Discovery_ImplPlatform.cpp
+++ b/src/lib/dnssd/Discovery_ImplPlatform.cpp
@@ -50,13 +50,33 @@
}
DiscoveredNodeData nodeData;
- result->ToDiscoveredNodeData(addresses, nodeData);
+
+ result->ToDiscoveredCommissionNodeData(addresses, nodeData);
nodeData.Get<CommissionNodeData>().LogDetail();
discoveryContext->OnNodeDiscovered(nodeData);
discoveryContext->Release();
}
+static void HandleNodeOperationalBrowse(void * context, DnssdService * result, CHIP_ERROR error)
+{
+ DiscoveryContext * discoveryContext = static_cast<DiscoveryContext *>(context);
+
+ if (error != CHIP_NO_ERROR)
+ {
+ discoveryContext->Release();
+ return;
+ }
+
+ DiscoveredNodeData nodeData;
+
+ result->ToDiscoveredOperationalNodeBrowseData(nodeData);
+
+ nodeData.Get<OperationalNodeBrowseData>().LogDetail();
+ discoveryContext->OnNodeDiscovered(nodeData);
+ discoveryContext->Release();
+}
+
static void HandleNodeBrowse(void * context, DnssdService * services, size_t servicesSize, bool finalBrowse, CHIP_ERROR error)
{
DiscoveryContext * discoveryContext = static_cast<DiscoveryContext *>(context);
@@ -75,8 +95,16 @@
auto & ipAddress = services[i].mAddress;
- // Check if SRV, TXT and AAAA records were received in DNS responses
- if (strlen(services[i].mHostName) == 0 || services[i].mTextEntrySize == 0 || !ipAddress.has_value())
+ // mType(service name) exactly matches with operational service name
+ bool isOperationalBrowse = strcmp(services[i].mType, kOperationalServiceName) == 0;
+
+ // For operational browse result we currently don't need IP address hence skip resolution and handle differently.
+ if (isOperationalBrowse)
+ {
+ HandleNodeOperationalBrowse(context, &services[i], error);
+ }
+ // check whether SRV, TXT and AAAA records were received in DNS responses
+ else if (strlen(services[i].mHostName) == 0 || services[i].mTextEntrySize == 0 || !ipAddress.has_value())
{
ChipDnssdResolve(&services[i], services[i].mInterface, HandleNodeResolve, context);
}
@@ -340,7 +368,15 @@
impl->mOperationalDelegate->OnOperationalNodeResolved(nodeData);
}
-void DnssdService::ToDiscoveredNodeData(const Span<Inet::IPAddress> & addresses, DiscoveredNodeData & nodeData)
+void DnssdService::ToDiscoveredOperationalNodeBrowseData(DiscoveredNodeData & nodeData)
+{
+ nodeData.Set<OperationalNodeBrowseData>();
+
+ ExtractIdFromInstanceName(mName, &nodeData.Get<OperationalNodeBrowseData>().peerId);
+ nodeData.Get<OperationalNodeBrowseData>().hasZeroTTL = (mTtlSeconds == 0);
+}
+
+void DnssdService::ToDiscoveredCommissionNodeData(const Span<Inet::IPAddress> & addresses, DiscoveredNodeData & nodeData)
{
nodeData.Set<CommissionNodeData>();
auto & discoveredData = nodeData.Get<CommissionNodeData>();
@@ -746,6 +782,31 @@
return error;
}
+CHIP_ERROR DiscoveryImplPlatform::DiscoverOperational(DiscoveryFilter filter, DiscoveryContext & context)
+{
+ ReturnErrorOnFailure(InitImpl());
+ StopDiscovery(context);
+
+ char serviceName[kMaxOperationalServiceNameSize];
+ ReturnErrorOnFailure(MakeServiceTypeName(serviceName, sizeof(serviceName), filter, DiscoveryType::kOperational));
+
+ intptr_t browseIdentifier;
+ // Increase the reference count of the context to keep it alive until HandleNodeBrowse is called back.
+ CHIP_ERROR error = ChipDnssdBrowse(serviceName, DnssdServiceProtocol::kDnssdProtocolTcp, Inet::IPAddressType::kAny,
+ Inet::InterfaceId::Null(), HandleNodeBrowse, context.Retain(), &browseIdentifier);
+
+ if (error == CHIP_NO_ERROR)
+ {
+ context.SetBrowseIdentifier(browseIdentifier);
+ }
+ else
+ {
+ context.Release();
+ }
+
+ return error;
+}
+
CHIP_ERROR DiscoveryImplPlatform::StartDiscovery(DiscoveryType type, DiscoveryFilter filter, DiscoveryContext & context)
{
switch (type)
@@ -755,7 +816,7 @@
case DiscoveryType::kCommissionerNode:
return DiscoverCommissioners(filter, context);
case DiscoveryType::kOperational:
- return CHIP_ERROR_NOT_IMPLEMENTED;
+ return DiscoverOperational(filter, context);
default:
return CHIP_ERROR_INVALID_ARGUMENT;
}
diff --git a/src/lib/dnssd/Discovery_ImplPlatform.h b/src/lib/dnssd/Discovery_ImplPlatform.h
index 34fedf8..d51d5e7 100644
--- a/src/lib/dnssd/Discovery_ImplPlatform.h
+++ b/src/lib/dnssd/Discovery_ImplPlatform.h
@@ -55,6 +55,7 @@
void NodeIdResolutionNoLongerNeeded(const PeerId & peerId) override;
CHIP_ERROR DiscoverCommissionableNodes(DiscoveryFilter filter, DiscoveryContext & context);
CHIP_ERROR DiscoverCommissioners(DiscoveryFilter filter, DiscoveryContext & context);
+ CHIP_ERROR DiscoverOperational(DiscoveryFilter filter, DiscoveryContext & context);
CHIP_ERROR StartDiscovery(DiscoveryType type, DiscoveryFilter filter, DiscoveryContext & context) override;
CHIP_ERROR StopDiscovery(DiscoveryContext & context) override;
CHIP_ERROR ReconfirmRecord(const char * hostname, Inet::IPAddress address, Inet::InterfaceId interfaceId) override;
diff --git a/src/lib/dnssd/ServiceNaming.cpp b/src/lib/dnssd/ServiceNaming.cpp
index 25bdfbf..8ec86a1 100644
--- a/src/lib/dnssd/ServiceNaming.cpp
+++ b/src/lib/dnssd/ServiceNaming.cpp
@@ -162,6 +162,10 @@
{
requiredSize = snprintf(buffer, bufferLen, kCommissionerServiceName);
}
+ else if (type == DiscoveryType::kOperational)
+ {
+ requiredSize = snprintf(buffer, bufferLen, kOperationalServiceName);
+ }
else
{
return CHIP_ERROR_NOT_IMPLEMENTED;
diff --git a/src/lib/dnssd/platform/Dnssd.h b/src/lib/dnssd/platform/Dnssd.h
index 02fb851..e1e4405 100644
--- a/src/lib/dnssd/platform/Dnssd.h
+++ b/src/lib/dnssd/platform/Dnssd.h
@@ -81,7 +81,8 @@
// Time to live in seconds. Per rfc6762 section 10, because we have a hostname, our default TTL is 120 seconds
uint32_t mTtlSeconds = 120;
- void ToDiscoveredNodeData(const Span<Inet::IPAddress> & addresses, DiscoveredNodeData & nodeData);
+ void ToDiscoveredCommissionNodeData(const Span<Inet::IPAddress> & addresses, DiscoveredNodeData & nodeData);
+ void ToDiscoveredOperationalNodeBrowseData(DiscoveredNodeData & nodeData);
};
/**
diff --git a/src/lib/shell/commands/Dns.cpp b/src/lib/shell/commands/Dns.cpp
index 65b3f7b..50be591 100644
--- a/src/lib/shell/commands/Dns.cpp
+++ b/src/lib/shell/commands/Dns.cpp
@@ -261,6 +261,13 @@
return sResolverProxy.DiscoverOperationalNodes(filter);
}
+CHIP_ERROR BrowseStopHandler(int argc, char ** argv)
+{
+ streamer_printf(streamer_get(), "Stopping browse...\r\n");
+
+ return sResolverProxy.StopDiscovery();
+}
+
} // namespace
void RegisterDnsCommands()
@@ -270,6 +277,8 @@
"Browse Matter commissionables. Usage: dns browse commissionable [subtype]" },
{ &BrowseCommissionerHandler, "commissioner", "Browse Matter commissioners. Usage: dns browse commissioner [subtype]" },
{ &BrowseOperationalHandler, "operational", "Browse Matter operational nodes. Usage: dns browse operational" },
+ { &BrowseStopHandler, "stop", "Stop ongoing browse. Usage: dns browse stop" },
+
};
static constexpr Command subCommands[] = {
diff --git a/src/platform/Darwin/DnssdContexts.cpp b/src/platform/Darwin/DnssdContexts.cpp
index 7dc5956..fc68a5d 100644
--- a/src/platform/Darwin/DnssdContexts.cpp
+++ b/src/platform/Darwin/DnssdContexts.cpp
@@ -607,7 +607,16 @@
{
auto delegate = static_cast<DiscoverNodeDelegate *>(context);
DiscoveredNodeData nodeData;
- service.ToDiscoveredNodeData(addresses, nodeData);
+
+ // Check whether mType (service name) exactly matches with operational service name
+ if (strcmp(service.mType, kOperationalServiceName) == 0)
+ {
+ service.ToDiscoveredOperationalNodeBrowseData(nodeData);
+ }
+ else
+ {
+ service.ToDiscoveredCommissionNodeData(addresses, nodeData);
+ }
delegate->OnNodeDiscovered(nodeData);
}
else
diff --git a/src/platform/Linux/DnssdImpl.cpp b/src/platform/Linux/DnssdImpl.cpp
index 800064f..40b7c89 100644
--- a/src/platform/Linux/DnssdImpl.cpp
+++ b/src/platform/Linux/DnssdImpl.cpp
@@ -611,9 +611,9 @@
{
avahiInterface = AVAHI_IF_UNSPEC;
}
- browseContext->mInterface = avahiInterface;
- browseContext->mProtocol = GetFullType(type, protocol);
- browseContext->mBrowseRetries = 0;
+ browseContext->mInterface = avahiInterface;
+ browseContext->mProtocol = GetFullType(type, protocol);
+ browseContext->mReceivedAllCached = false;
browseContext->mStopped.store(false);
browser = avahi_service_browser_new(mClient, avahiInterface, AVAHI_PROTO_UNSPEC, browseContext->mProtocol.c_str(), nullptr,
@@ -686,23 +686,22 @@
}
}
-void MdnsAvahi::BrowseRetryCallback(chip::System::Layer * aLayer, void * appState)
+void MdnsAvahi::InvokeDelegateOrCleanUp(BrowseContext * context, AvahiServiceBrowser * browser)
{
- BrowseContext * context = static_cast<BrowseContext *>(appState);
- // Don't schedule anything new if we've stopped.
- if (context->mStopped.load())
+ // If we were already asked to stop, no need to send a callback - no one is listening.
+ if (!context->mStopped.load())
{
- chip::Platform::Delete(context);
- return;
+ // since this is continuous browse, finalBrowse will always be false.
+ context->mCallback(context->mContext, context->mServices.data(), context->mServices.size(), false, CHIP_NO_ERROR);
+
+ // Clearing records/services already passed to application through delegate. Keeping it may cause
+ // duplicates in next query / retry attempt as currently found will also come again from cache.
+ context->mServices.clear();
}
- AvahiServiceBrowser * newBrowser =
- avahi_service_browser_new(context->mInstance->mClient, context->mInterface, AVAHI_PROTO_UNSPEC, context->mProtocol.c_str(),
- nullptr, static_cast<AvahiLookupFlags>(0), HandleBrowse, context);
- if (newBrowser == nullptr)
+ else
{
- // If we failed to create the browser, this browse context is effectively done. We need to call the final callback and
- // delete the context.
- context->mCallback(context->mContext, context->mServices.data(), context->mServices.size(), true, CHIP_NO_ERROR);
+ // browse is stopped, so free browse handle and context
+ avahi_service_browser_free(browser);
chip::Platform::Delete(context);
}
}
@@ -722,6 +721,13 @@
break;
case AVAHI_BROWSER_NEW:
ChipLogProgress(DeviceLayer, "Avahi browse: cache new");
+ if (context->mStopped.load())
+ {
+ // browse is stopped, so free browse handle and context
+ avahi_service_browser_free(browser);
+ chip::Platform::Delete(context);
+ break;
+ }
if (strcmp("local", domain) == 0)
{
DnssdService service = {};
@@ -738,41 +744,53 @@
}
service.mType[kDnssdTypeMaxSize] = 0;
context->mServices.push_back(service);
+ if (context->mReceivedAllCached)
+ {
+ InvokeDelegateOrCleanUp(context, browser);
+ }
}
break;
case AVAHI_BROWSER_ALL_FOR_NOW: {
ChipLogProgress(DeviceLayer, "Avahi browse: all for now");
- bool needRetries = context->mBrowseRetries++ < kMaxBrowseRetries && !context->mStopped.load();
- // If we were already asked to stop, no need to send a callback - no one is listening.
- if (!context->mStopped.load())
- {
- context->mCallback(context->mContext, context->mServices.data(), context->mServices.size(), !needRetries,
- CHIP_NO_ERROR);
- }
- avahi_service_browser_free(browser);
- if (needRetries)
- {
- context->mNextRetryDelay *= 2;
- // Hand the ownership of the context over to the timer. It will either schedule a new browse on the context,
- // triggering this function, or it will delete and not reschedule (if stopped).
- DeviceLayer::SystemLayer().StartTimer(context->mNextRetryDelay / 2, BrowseRetryCallback, context);
- }
- else
- {
- // We didn't schedule a timer, so we're responsible for deleting the context
- chip::Platform::Delete(context);
- }
+ context->mReceivedAllCached = true;
+
+ InvokeDelegateOrCleanUp(context, browser);
break;
}
case AVAHI_BROWSER_REMOVE:
ChipLogProgress(DeviceLayer, "Avahi browse: remove");
if (strcmp("local", domain) == 0)
{
- context->mServices.erase(
- std::remove_if(context->mServices.begin(), context->mServices.end(), [name, type](const DnssdService & service) {
- return strcmp(name, service.mName) == 0 && type == GetFullType(service.mType, service.mProtocol);
- }));
+ // don't attempt to erase if vector has been cleared
+ if (context->mServices.size())
+ {
+ context->mServices.erase(std::remove_if(
+ context->mServices.begin(), context->mServices.end(), [name, type](const DnssdService & service) {
+ return strcmp(name, service.mName) == 0 && type == GetFullType(service.mType, service.mProtocol);
+ }));
+ }
+
+ if (context->mReceivedAllCached)
+ {
+ DnssdService service = {};
+
+ Platform::CopyString(service.mName, name);
+ CopyTypeWithoutProtocol(service.mType, type);
+ service.mProtocol = GetProtocolInType(type);
+ service.mAddressType = context->mAddressType;
+ service.mTransportType = ToAddressType(protocol);
+ service.mInterface = Inet::InterfaceId::Null();
+ if (interface != AVAHI_IF_UNSPEC)
+ {
+ service.mInterface = static_cast<chip::Inet::InterfaceId>(interface);
+ }
+ service.mTtlSeconds = 0;
+
+ context->mServices.push_back(service);
+ InvokeDelegateOrCleanUp(context, browser);
+ }
}
+
break;
case AVAHI_BROWSER_CACHE_EXHAUSTED:
ChipLogProgress(DeviceLayer, "Avahi browse: cache exhausted");
diff --git a/src/platform/Linux/DnssdImpl.h b/src/platform/Linux/DnssdImpl.h
index c66a8c2..f1de8db 100644
--- a/src/platform/Linux/DnssdImpl.h
+++ b/src/platform/Linux/DnssdImpl.h
@@ -131,11 +131,11 @@
void * mContext;
Inet::IPAddressType mAddressType;
std::vector<DnssdService> mServices;
- size_t mBrowseRetries;
+ bool mReceivedAllCached;
AvahiIfIndex mInterface;
std::string mProtocol;
- chip::System::Clock::Timeout mNextRetryDelay = chip::System::Clock::Seconds16(1);
std::atomic_bool mStopped{ false };
+ AvahiServiceBrowser * mBrowser;
};
struct ResolveContext
@@ -181,7 +181,7 @@
static void HandleBrowse(AvahiServiceBrowser * broswer, AvahiIfIndex interface, AvahiProtocol protocol, AvahiBrowserEvent event,
const char * name, const char * type, const char * domain, AvahiLookupResultFlags flags,
void * userdata);
- static void BrowseRetryCallback(chip::System::Layer * aLayer, void * appState);
+ static void InvokeDelegateOrCleanUp(BrowseContext * context, AvahiServiceBrowser * browser);
static void HandleResolve(AvahiServiceResolver * resolver, AvahiIfIndex interface, AvahiProtocol protocol,
AvahiResolverEvent event, const char * name, const char * type, const char * domain,
const char * host_name, const AvahiAddress * address, uint16_t port, AvahiStringList * txt,
