initial serial client implementation for meshcore device

src/buffer_reader.js

@@ -0,0 +1,53 @@
+class BufferReader {
+
+    constructor(data) {
+        this.pointer = 0;
+        this.buffer = new Uint8Array(data);
+    }
+
+    readByte() {
+        return this.readBytes(1)[0];
+    }
+
+    readBytes(count) {
+        const data = this.buffer.slice(this.pointer, this.pointer + count);
+        this.pointer += count;
+        return data;
+    }
+
+    readString() {
+        const remainingBytesCount = this.buffer.length - this.pointer;
+        const remainingBytes = this.readBytes(remainingBytesCount);
+        return new TextDecoder().decode(remainingBytes);
+    }
+
+    readCString(maxLength) {
+        const value = [];
+        const bytes = this.readBytes(maxLength);
+        for(const byte of bytes){
+
+            // if we find a null terminator character, we have reached the end of the cstring
+            if(byte === 0){
+                return new TextDecoder().decode(new Uint8Array(value));
+            }
+
+            value.push(byte);
+
+        }
+    }
+
+    readUInt16LE() {
+        const bytes = this.readBytes(2);
+        const view = new DataView(bytes.buffer);
+        return view.getUint16(0, true);
+    }
+
+    readUInt32LE() {
+        const bytes = this.readBytes(4);
+        const view = new DataView(bytes.buffer);
+        return view.getUint32(0, true);
+    }
+
+}
+
+export default BufferReader;