start implementation of NBT parser

src/lib/nbt.cpp

@@ -1,6 +1,12 @@
 #include <bit>
+#include <cstdint>
+#include <vector>
 
-// This is just an example for how to find out if the system is big endian or little endian. Do not use this.
+#include "nbt.h++"
+#include "error.h++"
+
+// This is just an example for how to find out if the system is big endian
+// or little endian. Do not use this.
 int endianness_example() {
     if constexpr (std::endian::native == std::endian::big)
     {
@@ -20,3 +26,74 @@ int endianness_example() {
     }
 }
 
+namespace NBT {
+    namespace helpers {
+        ErrorOr<int8_t> readByte(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<int8_t>(0);
+        }
+
+        ErrorOr<int16_t> readInt16(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<int16_t>(0);
+        }
+
+        ErrorOr<int32_t> readInt32(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<int32_t>(0);
+        }
+
+        ErrorOr<int64_t> readInt64(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<int64_t>(0);
+        }
+
+        //FIXME: we just assume that float is a single-precision IEEE754
+        // floating point number
+        ErrorOr<float> readFloat32(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement assuming standard single-precision IEEE754 float
+            // Alternatively, maybe calculate a floating point number by using
+            // the stored value as math instructions?
+            return ErrorOr<float>(0.0f);
+        }
+
+        //FIXME: we just assume that double is a double-precision IEEE754
+        // floating point number
+        ErrorOr<double> readFloat64(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement assuming standard double-precision IEEE754 float
+            // Alternatively, maybe calculate a floating point number by using
+            // the stored value as math instructions?
+            return ErrorOr<double>(0.0);
+        }
+
+        ErrorOr<std::vector<int8_t>> readByteArray(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<std::vector<int8_t>>({0});
+        }
+
+        //TODO: find suitable string type
+        // Maybe use a struct that holds decoded (de-Java-fied) string
+        // data, decoded size, and original size? Original size is needed
+        // so the parser knows where to continue.
+        //ErrorOr<> readString(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            // return ErrorOr<>("");
+        //}
+
+        ErrorOr<std::vector<int32_t>> readInt32Array(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<std::vector<int32_t>>({0});
+        }
+
+        ErrorOr<std::vector<int64_t>> readInt64Array(uint8_t* data[], uint64_t dataSize, uint64_t currentPosition) {
+            //TODO: implement
+            return ErrorOr<std::vector<int64_t>>({0});
+        }
+    }
+
+    bool validateRawNBTData(uint8_t* data[], uint64_t dataSize){
+        //state machine?
+        //TODO: implement
+        return false;
+    }
+}

src/lib/nbt.h++

@@ -18,3 +18,12 @@
 // Tag[] (compound):        Tag(10, String:name, uint16:name_size, Tag[]:content,  int32:size) => list of tags, last tag is always an end tag, size not stored
 // int32[]:                 Tag(11, String:name, uint16:name_size, int32[]:content,int32:size) => list of 32 bit signed integers prefixed with its size, endianness not verified at this point
 // int64[]:                 Tag(12, String:name, uint16:name_size, int64[]:content,int32:size) => list of 64 bit signed integers prefixed with its size, endianness not verified at this point
+
+#pragma once
+#include <cstdint>
+#include <vector>
+#include "error.h++"
+
+namespace NBT {
+    bool validateRawNBTData(uint8_t* data[], int length);
+}