feat: decoder consume with offset. testing: DecoderTester class

Author: eigen-value

examples/decoder_tests/decoder_tester.h

@@ -0,0 +1,31 @@
+#pragma once
+#ifndef RPCLITE_DECODER_TESTER_H
+#define RPCLITE_DECODER_TESTER_H
+
+class DecoderTester {
+  
+  RpcDecoder<>& decoder;
+
+public:
+
+  DecoderTester(RpcDecoder<>& _d): decoder(_d){}
+
+  void crop_bytes(size_t size, size_t offset){
+    decoder.consume(size, offset);
+  }
+
+  void print_raw_buf(){
+
+    Serial.print("Decoder raw buffer content: ");
+
+    for (size_t i = 0; i < decoder._bytes_stored; i++) {
+
+        Serial.print(decoder._raw_buffer[i], HEX);
+        Serial.print(" ");
+    }
+    Serial.println("");
+  }
+
+};
+
+#endif // RPCLITE_DECODER_TESTER_H

examples/decoder_tests/decoder_tests.ino

@@ -1,5 +1,6 @@
 #include <Arduino_RPClite.h>
 #include "DummyTransport.h"
+#include "decoder_tester.h"
 
 // Shorthand
 MsgPack::Packer packer;
@@ -36,6 +37,35 @@ void runDecoderTest(const char* label) {
   Serial.println("-- Done --\n");
 }
 
+void runDecoderConsumeTest(const char* label, size_t second_packet_sz) {
+  Serial.println(label);
+
+  print_buf();
+  DummyTransport dummy_transport(packer.data(), packer.size());
+  RpcDecoder<> decoder(dummy_transport);
+
+  DecoderTester dt(decoder);
+
+  while (!decoder.packet_incoming()) {
+    Serial.println("Packet not ready");
+    decoder.decode();
+    delay(50);
+  }
+
+  size_t pack_size = decoder.get_packet_size();
+  Serial.print("1st Packet size: ");
+  Serial.println(pack_size);
+
+  Serial.print("Consuming 2nd packet of given size: ");
+  Serial.println(second_packet_sz);
+
+  dt.crop_bytes(second_packet_sz, pack_size);
+
+  dt.print_raw_buf();
+
+  Serial.println("-- Done --\n");
+}
+
 void testNestedArrayRequest() {
   packer.clear();
   MsgPack::arr_size_t outer_arr(3);
@@ -120,6 +150,9 @@ void testMultipleRpcPackets() {
   packer.serialize(req_sz, 0, 2, "echo", par_sz, "Hello", true);
 
   runDecoderTest("== Test: Multiple RPCs in Buffer ==");
+
+  runDecoderConsumeTest("== Test: Mid-buffer consume ==", 5);
+
 }
 
 // Binary parameter (e.g., binary blob)
@@ -170,6 +203,8 @@ void testCombinedComplexBuffer() {
 
 void setup() {
   Serial.begin(115200);
+  while(!Serial);
+  
   delay(1000);
   Serial.println("=== RPC Decoder Nested Tests ===");
 

src/decoder.h

@@ -151,6 +151,8 @@ class RpcDecoder {
 
     inline size_t size() const {return _bytes_stored;}
 
+    friend class DecoderTester;
+
 private:
     ITransport& _transport;
     uint8_t _raw_buffer[BufferSize];
@@ -188,22 +190,19 @@ class RpcDecoder {
         _packet_size = 0;
     }
 
-    size_t consume(size_t size) {
-
-        if (size > _bytes_stored) return 0;
-
-        const size_t remaining_bytes = _bytes_stored - size;
-
-        // Shift remaining data forward (manual memmove for compatibility)
-        for (size_t i = 0; i < remaining_bytes; i++) {
-            _raw_buffer[i] = _raw_buffer[size + i];
-        }
-
-        _bytes_stored = remaining_bytes;
-
-        return size;
+size_t consume(size_t size, size_t offset = 0) {
+    // Boundary checks
+    if (offset + size >= _bytes_stored || size == 0) return 0;
+    
+    size_t remaining_bytes = _bytes_stored - size;
+    for (size_t i=offset; i<remaining_bytes; i++){
+        _raw_buffer[i] = _raw_buffer[i+size];
     }
 
+    _bytes_stored = remaining_bytes;
+    return size;
+}
+
 };
 
 #endif