AdsNotification: allow dynamic sized samples

It seems some ADS devices like AMSPORT_LOGGER will send notifications with variable sizes. To support them we can lessen our size check, but we have to pass the real size to Notification::Notify() Signed-off-by: Patrick Bruenn <[email protected]>
Beckhoff · Dec 20, 2024 · a898434 · a898434
1 parent e85ef69
commit a898434
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Showing 2 changed files with 11 additions and 9 deletions.
diff --git a/AdsLib/AdsNotification.h b/AdsLib/AdsNotification.h
@@ -23,28 +23,29 @@ struct Notification {
         : connection({__port, __amsAddr}),
         callback(__func),
         buffer(sizeof(AdsNotificationHeader) + length),
-        hUser(__hUser)
+        hUser(__hUser),
+        size(length)
     {
         auto header = reinterpret_cast<AdsNotificationHeader*>(buffer.data());
         header->hNotification = 0;
         header->cbSampleSize = length;
     }
 
-    void Notify(uint64_t timestamp, RingBuffer& ring)
+    void Notify(RingBuffer& ring, const uint64_t timestamp, const uint32_t sampleSize)
     {
         auto header = reinterpret_cast<AdsNotificationHeader*>(buffer.data());
         uint8_t* data = reinterpret_cast<uint8_t*>(header + 1);
-        for (size_t i = 0; i < header->cbSampleSize; ++i) {
+        header->cbSampleSize = sampleSize;
+        header->nTimeStamp = timestamp;
+        for (size_t i = 0; i < sampleSize; ++i) {
             data[i] = ring.ReadFromLittleEndian<uint8_t>();
         }
-        header->nTimeStamp = timestamp;
         callback(&connection.second, header, hUser);
     }
 
     uint32_t Size() const
     {
-        auto header = reinterpret_cast<const AdsNotificationHeader*>(buffer.data());
-        return header->cbSampleSize;
+        return size;
     }
 
     void hNotify(uint32_t value)
@@ -57,4 +58,5 @@ struct Notification {
     const PAdsNotificationFuncEx callback;
     std::vector<uint8_t> buffer;
     const uint32_t hUser;
+    const uint32_t size;
 };
diff --git a/AdsLib/standalone/NotificationDispatcher.cpp b/AdsLib/standalone/NotificationDispatcher.cpp
@@ -72,11 +72,11 @@ void NotificationDispatcher::Run()
                 fullLength -= sizeof(hNotify) + sizeof(size);
                 const auto notification = Find(hNotify);
                 if (notification) {
-                    if (size != notification->Size()) {
-                        LOG_WARN("Notification sample size: " << size << " doesn't match: " << notification->Size());
+                    if (size > notification->Size()) {
+                        LOG_WARN("Notification sample size: " << size << " to large: " << notification->Size());
                         goto cleanup;
                     }
-                    notification->Notify(timestamp, ring);
+                    notification->Notify(ring, timestamp, size);
                 } else {
                     ring.Read(size);
                 }