Added stream writer and reader. Updated readme.

Common/StreamReader.go

@@ -0,0 +1,51 @@
+package Common
+
+// StreamReader allows you to read data from a byte array in various formats
+type StreamReader struct {
+	data     []byte
+	position uint64
+}
+
+// CreateStreamReader creates an instance of the stream reader
+func CreateStreamReader(source []byte) *StreamReader {
+	result := &StreamReader{
+		data:     source,
+		position: 0,
+	}
+	return result
+}
+
+// GetPosition returns the current stream position
+func (v *StreamReader) GetPosition() uint64 {
+	return v.position
+}
+
+// GetSize returns the total size of the stream in bytes
+func (v *StreamReader) GetSize() uint64 {
+	return uint64(len(v.data))
+}
+
+// GetByte returns a byte from the stream
+func (v *StreamReader) GetByte() byte {
+	result := v.data[v.position]
+	v.position++
+	return result
+}
+
+// GetWord returns a uint16 word from the stream
+func (v *StreamReader) GetWord() uint16 {
+	result := uint16(v.data[v.position])
+	result += (uint16(v.data[v.position+1]) << 8)
+	v.position += 2
+	return result
+}
+
+// GetDword returns a uint32 dword from the stream
+func (v *StreamReader) GetDword() uint32 {
+	result := uint32(v.data[v.position])
+	result += (uint32(v.data[v.position+1]) << 8)
+	result += (uint32(v.data[v.position+2]) << 16)
+	result += (uint32(v.data[v.position+3]) << 24)
+	v.position += 4
+	return result
+}

Common/StreamReader_test.go

@@ -0,0 +1,56 @@
+package Common
+
+import (
+	"testing"
+)
+
+func TestStreamReaderByte(t *testing.T) {
+	data := []byte{0x78, 0x56, 0x34, 0x12}
+	sr := CreateStreamReader(data)
+	if sr.GetPosition() != 0 {
+		t.Fatal("StreamReader.GetPosition() did not start at 0")
+	}
+	if ss := sr.GetSize(); ss != 4 {
+		t.Fatalf("StreamREader.GetSize() was expected to return %d, but returned %d instead", 4, ss)
+	}
+	for i := 0; i < len(data); i++ {
+		ret := sr.GetByte()
+		if ret != data[i] {
+			t.Fatalf("StreamReader.GetDword() was expected to return %X, but returned %X instead", data[i], ret)
+		}
+		if pos := sr.GetPosition(); pos != uint64(i+1) {
+			t.Fatalf("StreamReader.GetPosition() should be at %d, but was at %d instead", i, pos)
+		}
+	}
+}
+
+func TestStreamReaderWord(t *testing.T) {
+	data := []byte{0x78, 0x56, 0x34, 0x12}
+	sr := CreateStreamReader(data)
+	ret := sr.GetWord()
+	if ret != 0x5678 {
+		t.Fatalf("StreamReader.GetDword() was expected to return %X, but returned %X instead", 0x5678, ret)
+	}
+	if pos := sr.GetPosition(); pos != 2 {
+		t.Fatalf("StreamReader.GetPosition() should be at %d, but was at %d instead", 2, pos)
+	}
+	ret = sr.GetWord()
+	if ret != 0x1234 {
+		t.Fatalf("StreamReader.GetDword() was expected to return %X, but returned %X instead", 0x1234, ret)
+	}
+	if pos := sr.GetPosition(); pos != 4 {
+		t.Fatalf("StreamReader.GetPosition() should be at %d, but was at %d instead", 4, pos)
+	}
+}
+
+func TestStreamReaderDword(t *testing.T) {
+	data := []byte{0x78, 0x56, 0x34, 0x12}
+	sr := CreateStreamReader(data)
+	ret := sr.GetDword()
+	if ret != 0x12345678 {
+		t.Fatalf("StreamReader.GetDword() was expected to return %X, but returned %X instead", 0x12345678, ret)
+	}
+	if pos := sr.GetPosition(); pos != 4 {
+		t.Fatalf("StreamReader.GetPosition() should be at %d, but was at %d instead", 4, pos)
+	}
+}

Common/StreamWriter.go

@@ -0,0 +1,37 @@
+package Common
+
+// StreamWriter allows you to create a byte array by streaming in writes of various sizes
+type StreamWriter struct {
+	data []byte
+}
+
+// CreateStreamWriter creates a new StreamWriter instance
+func CreateStreamWriter() *StreamWriter {
+	result := &StreamWriter{
+		data: make([]byte, 0),
+	}
+	return result
+}
+
+// PushByte writes a byte to the stream
+func (v *StreamWriter) PushByte(val byte) {
+	v.data = append(v.data, val)
+}
+
+// PushWord writes an uint16 word to the stream
+func (v *StreamWriter) PushWord(val uint16) {
+	v.data = append(v.data, byte(val&0xFF))
+	v.data = append(v.data, byte((val>>8)&0xFF))
+}
+
+// PushDword writes a uint32 dword to the stream
+func (v *StreamWriter) PushDword(val uint32) {
+	v.data = append(v.data, byte(val&0xFF))
+	v.data = append(v.data, byte((val>>8)&0xFF))
+	v.data = append(v.data, byte((val>>16)&0xFF))
+	v.data = append(v.data, byte((val>>24)&0xFF))
+}
+
+func (v *StreamWriter) GetBytes() []byte {
+	return v.data
+}

Common/StreamWriter_test.go

@@ -0,0 +1,44 @@
+package Common
+
+import (
+	"testing"
+)
+
+func TestStreamWriterByte(t *testing.T) {
+	sr := CreateStreamWriter()
+	data := []byte{0x12, 0x34, 0x56, 0x78}
+	for _, d := range data {
+		sr.PushByte(d)
+	}
+	output := sr.GetBytes()
+	for i, d := range data {
+		if output[i] != d {
+			t.Fatalf("sr.PushByte() pushed %X, but wrote %X instead", d, output[i])
+		}
+	}
+}
+
+func TestStreamWriterWord(t *testing.T) {
+	sr := CreateStreamWriter()
+	data := []byte{0x12, 0x34, 0x56, 0x78}
+	sr.PushWord(0x3412)
+	sr.PushWord(0x7856)
+	output := sr.GetBytes()
+	for i, d := range data {
+		if output[i] != d {
+			t.Fatalf("sr.PushWord() pushed byte %X to %d, but %X was expected instead", output[i], i, d)
+		}
+	}
+}
+
+func TestStreamWriterDword(t *testing.T) {
+	sr := CreateStreamWriter()
+	data := []byte{0x12, 0x34, 0x56, 0x78}
+	sr.PushDword(0x78563412)
+	output := sr.GetBytes()
+	for i, d := range data {
+		if output[i] != d {
+			t.Fatalf("sr.PushDword() pushed byte %X to %d, but %X was expected instead", output[i], i, d)
+		}
+	}
+}

README.md

@@ -29,9 +29,39 @@ To run the project, run `go run ./cmd/Client` from the root folder.
 
 You can also open the root folder in VSCode. Make sure you have the `ms-vscode.go` plugin installed.
 
+## VS Code Extensions
+
+The following extensions are recommended for working with this project:
+ * ms-vscode.go
+ * defaltd.go-coverage-viewer
+
+For the Go extension, it is recommended you add the following to settings.json:
+```json
+    "go.languageServerExperimentalFeatures": {
+        "format": true,
+        "autoComplete": true,
+        "rename": true,
+        "goToDefinition": true,
+        "hover": true,
+        "signatureHelp": true,
+        "goToTypeDefinition": true,
+        "goToImplementation": true,
+        "documentSymbols": true,
+        "workspaceSymbols": true,
+        "findReferences": true,
+        "diagnostics": true,
+        "documentLink": true
+    },
+```
+
+You can get to it by going to settings <kbd>Ctrl+,</kbd>, expanding `Extensions` and selecting `Go configuration`,
+then clicking on `Edit in settings.json`. Just paste that section where appropriate.
+
 ## Configuration
 
-The engine is configured via the `config.json` file.
+The engine is configured via the `config.json` file. By default, the configuration assumes that you have installed Diablo 2 and the
+expansion via the official Blizzard Diablo2 installers using the default file paths. If you are not on Windows, or have installed
+the game in a different location, the base path may have to be adjusted.
 
 
 ## Contributing