add comments for TelegramBuffer::takeTelegramFrames

verilog-to-routing · Apr 2, 2024 · df28932 · df28932
1 parent 0c42d0b
commit df28932
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/vpr/src/server/telegrambuffer.cpp b/vpr/src/server/telegrambuffer.cpp
@@ -7,11 +7,12 @@ void TelegramBuffer::append(const ByteArray& bytes)
     m_rawBuffer.append(bytes);
 }
 
-bool TelegramBuffer::checkRawBuffer()
+bool TelegramBuffer::checkTelegramHeaderPresence()
 {
     std::size_t signatureStartIndex = m_rawBuffer.findSequence(TelegramHeader::SIGNATURE, TelegramHeader::SIGNATURE_SIZE);
     if (signatureStartIndex != std::size_t(-1)) {
         if (signatureStartIndex != 0) {
+            // discard bytes preceding the header start position.
             m_rawBuffer.erase(m_rawBuffer.begin(), m_rawBuffer.begin()+signatureStartIndex);
         }
         return true;
@@ -28,24 +29,28 @@ void TelegramBuffer::takeTelegramFrames(std::vector<comm::TelegramFramePtr>& res
     bool mayContainFullTelegram = true; 
     while(mayContainFullTelegram) { 
         mayContainFullTelegram = false;
+        // attempt to extract telegram header
         if (!m_headerOpt) {
-            if (checkRawBuffer()) {
+            if (checkTelegramHeaderPresence()) {
                 TelegramHeader header(m_rawBuffer);
                 if (header.isValid()) {
                     m_headerOpt = std::move(header);
                 }
             }
         }
 
+        // attempt to extract telegram frame based on the telegram header
         if (m_headerOpt) {
             const TelegramHeader& header = m_headerOpt.value();
             std::size_t wholeTelegramSize = TelegramHeader::size() + header.bodyBytesNum();
             if (m_rawBuffer.size() >= wholeTelegramSize) {
+                // checksum validation
                 ByteArray data(m_rawBuffer.begin() + TelegramHeader::size(), m_rawBuffer.begin() + wholeTelegramSize);
                 uint32_t actualCheckSum = data.calcCheckSum();
                 if (actualCheckSum == header.bodyCheckSum()) {
+                    // construct telegram frame if checksum matches
                     TelegramFramePtr telegramFramePtr = std::make_shared<TelegramFrame>(TelegramFrame{header, std::move(data)});
-                    data.clear();
+                    data.clear(); // post std::move safety step
                     result.push_back(telegramFramePtr);                    
                 } else {
                     m_errors.push_back("wrong checkSums " + std::to_string(actualCheckSum) +" for " + header.info() + " , drop this chunk");

diff --git a/vpr/src/server/telegrambuffer.h b/vpr/src/server/telegrambuffer.h
@@ -72,7 +72,7 @@ class TelegramBuffer
     std::vector<std::string> m_errors;
     std::optional<TelegramHeader> m_headerOpt;
 
-    bool checkRawBuffer();
+    bool checkTelegramHeaderPresence();
 };
 
 } // namespace comm