Simplify _write_row_packet by precomputing header and lengths

ayushsharma82 · Jun 3, 2024 · 70dfd64 · 70dfd64
1 parent a079df4
commit 70dfd64
Showing 1 changed file with 23 additions and 28 deletions.
diff --git a/src/WebSerial.cpp b/src/WebSerial.cpp
@@ -18,6 +18,24 @@ typedef enum {
 static const uint8_t WSL_PONG[] = {WSL_MAGIC_BYTE_1, WSL_MAGIC_BYTE_2, WSLPacketType::WSL_PONG};
 static const size_t WSL_PONG_LEN = sizeof(WSL_PONG) / sizeof(WSL_PONG[0]);
 
+static const uint8_t WSL_HEAD[] = {
+  WSL_MAGIC_BYTE_1,             // Magic Bytes
+  WSL_MAGIC_BYTE_2,             // Magic Bytes
+  WSLPacketType::WSL_WRITE_ROW, // Packet Type (1 byte)
+  0x00,                         // Reserved
+  0x00,                         // Reserved
+  0x00,                         // Reserved
+  0x00,                         // Reserved
+  0x00,                         // Padding
+  0x00,                         // Padding
+  0x00,                         // Padding
+  0x00,                         // Padding
+  0x00                          // Reserved
+};
+static const size_t WSL_HEAD_LEN = sizeof(WSL_HEAD) / sizeof(WSL_HEAD[0]);
+
+static const size_t WSL_MSG_SIZE_LEN = sizeof(uint16_t);
+
 void WebSerialClass::setAuthentication(const String& username, const String& password){
   _username = username;
   _password = password;
@@ -142,37 +160,14 @@ bool WebSerialClass::_has_enough_space(size_t size) {
 }
 
 size_t WebSerialClass::_write_row_packet(__unused uint64_t reserved1, __unused uint8_t reserved2, const uint8_t *payload, const size_t payload_size) {
-  size_t header_size = 0;
-
-  // Write Magic Bytes
-  _buffer[_buffer_offset + header_size++] = WSL_MAGIC_BYTE_1;
-  _buffer[_buffer_offset + header_size++] = WSL_MAGIC_BYTE_2;
-
-  // Packet Type (1 byte)
-  _buffer[_buffer_offset + header_size++] = WSLPacketType::WSL_WRITE_ROW;
-
-  // Reserved (8 bytes)
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-  _buffer[_buffer_offset + header_size++] = 0x00;
-
-  // Reserved (1 byte)
-  _buffer[_buffer_offset + header_size++] = 0x00;
-
+  // Write header
+  memmove(_buffer, WSL_HEAD, WSL_HEAD_LEN);
   // Message Length (2 bytes)
-  memset(_buffer + _buffer_offset + header_size, (uint16_t)payload_size, sizeof((uint16_t)payload_size));
-  header_size += sizeof((uint16_t)payload_size);
-
+  memset(_buffer + WSL_HEAD_LEN, static_cast<uint16_t>(payload_size), WSL_MSG_SIZE_LEN);
   // Set Message
-  memcpy(_buffer + _buffer_offset + header_size, payload, payload_size);
-
+  memmove(_buffer + WSL_HEAD_LEN + WSL_MSG_SIZE_LEN, payload, payload_size);
   // Return total packet size
-  return header_size + payload_size;
+  return WSL_HEAD_LEN + WSL_MSG_SIZE_LEN + payload_size;
 }
 
 size_t WebSerialClass::_write_row(uint8_t *data, size_t len) {