feat(tracker): go generate parses gm.dls and show slightly more sane gui for them

cmd/sointu-generate/main.go

@@ -0,0 +1,131 @@
+// +build ignore
+package main
+
+import (
+	"encoding/binary"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+
+	"github.com/vsariola/sointu/tracker"
+)
+
+type riffVisitor interface {
+	Enter(listType string)
+	Leave(listType string)
+	Visit(filePos int, chunkType string, data []byte)
+}
+
+type gmDlsVisitor struct {
+	outputFile io.Writer
+	entry      tracker.GmDlsEntry
+	dataLength int
+	count      int
+}
+
+func (v *gmDlsVisitor) Enter(listType string) {
+	if listType == "wave" {
+		v.entry = tracker.GmDlsEntry{}
+		v.dataLength = 0
+	}
+}
+
+func (v *gmDlsVisitor) Leave(listType string) {
+	if listType == "wave" {
+		if v.entry.LoopLength == 0 {
+			v.entry.LoopStart = v.dataLength/2 - 1
+			v.entry.LoopLength = 1
+		}
+		if v.entry.Name == "" {
+			v.entry.Name = fmt.Sprintf("#%v", v.count)
+		}
+		fmt.Fprintf(v.outputFile, "\t{Start: %v, LoopStart: %v, LoopLength: %v, SuggestedTranspose: %v, Name: \"%v\"},\n", v.entry.Start, v.entry.LoopStart, v.entry.LoopLength, v.entry.SuggestedTranspose, v.entry.Name)
+		v.count++
+	}
+}
+
+func (v *gmDlsVisitor) Visit(filePos int, chunkType string, data []byte) {
+	switch chunkType {
+	case "wsmp":
+		v.entry.SuggestedTranspose = 60 - int(binary.LittleEndian.Uint16(data[4:6]))
+		numLoops := binary.LittleEndian.Uint32(data[16:20])
+		if numLoops > 0 {
+			v.entry.LoopStart = int(binary.LittleEndian.Uint32(data[28:32]))
+			v.entry.LoopLength = int(binary.LittleEndian.Uint32(data[32:36]))
+		}
+	case "data":
+		v.entry.Start = filePos / 2
+		v.dataLength = len(data)
+	case "INAM":
+		v.entry.Name = string(data[:len(data)-1])
+	}
+}
+
+func readChunk(filePos int, reader io.Reader, visitor riffVisitor) int {
+	var chunkType [4]byte
+	n, err := io.ReadFull(reader, chunkType[:])
+	check(err)
+	if n < 4 {
+		panic("did not get full 4 bytes for a chunktype")
+	}
+	filePos += n
+	chunkTypeString := string(chunkType[:])
+	var chunkLength int32
+	check(binary.Read(reader, binary.LittleEndian, &chunkLength))
+	filePos += 4
+	if chunkTypeString == "RIFF" || chunkTypeString == "LIST" {
+		end := filePos + int(chunkLength)
+		var listType [4]byte
+		n, err := io.ReadFull(reader, listType[:])
+		check(err)
+		if n < 4 {
+			panic("did not get full 4 bytes for a subchunkname")
+		}
+		filePos += n
+		listTypeString := string(listType[:])
+		visitor.Enter(listTypeString)
+		for filePos < end {
+			filePos = readChunk(filePos, reader, visitor)
+		}
+		visitor.Leave(listTypeString)
+	} else {
+		data := make([]byte, chunkLength)
+		n, err := reader.Read(data)
+		check(err)
+		if n < int(chunkLength) {
+			panic(fmt.Sprintf("chunk %v was supposed to be %v bytes, got %v bytes", chunkTypeString, chunkLength, n))
+		}
+		visitor.Visit(filePos, chunkTypeString, data)
+		filePos += n
+	}
+	if chunkLength&1 == 1 {
+		io.CopyN(ioutil.Discard, reader, 1)
+		filePos++
+	}
+	return filePos
+}
+
+func check(e error) {
+	if e != nil {
+		panic(e)
+	}
+}
+
+func main() {
+	inputFile, err := os.Open("C:\\Windows\\System32\\drivers\\gm.dls")
+	check(err)
+	defer inputFile.Close()
+	//_, myname, _, _ := runtime.Caller(0)
+	//outputFilePath := path.Join(path.Dir(myname), "gmdlsentries.go")
+	//check(err)
+	outputFile, err := os.Create("gmdlsentries.go")
+	check(err)
+	defer outputFile.Close()
+	fmt.Fprintln(outputFile, "// Code generated by go generate; DO NOT EDIT.")
+	fmt.Fprintln(outputFile, "package tracker")
+	fmt.Fprintln(outputFile, "")
+	fmt.Fprintln(outputFile, "var gmDlsEntries = []GmDlsEntry{")
+	readChunk(0, inputFile, &gmDlsVisitor{outputFile: outputFile})
+	fmt.Fprintln(outputFile, "}")
+}