1 files changed, 54 insertions, 0 deletions
diff --git a/mkvlib/shared.go b/mkvlib/shared.go
new file mode 100644
index 0000000..b0cfb2f
--- /dev/null
+++ b/mkvlib/shared.go
@@ -0,0 +1,54 @@
+package mkvlib
+
+import (
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+)
+
+const libName = "mkvlib"
+const libVer = "v1.0.2"
+
+const LibFName = libName + " " + libVer
+
+var _instance *mkvProcessor
+
+func GetInstance() *mkvProcessor {
+	ec := 0
+	n := "PATH"
+	s := ":"
+	if runtime.GOOS == "windows" {
+		n = "path"
+		s = ";"
+	}
+	p := os.Getenv(n)
+	if !strings.HasSuffix(p, s) {
+		p += s
+	}
+	e, _ := os.Executable()
+	e, _ = filepath.Split(e)
+	p += e
+	_ = os.Setenv(n, p)
+	_, _ttx := exec.LookPath(ttx)
+	_, _pyftsubset := exec.LookPath(pyftsubset)
+	_, _mkvextract := exec.LookPath(mkvextract)
+	_, _mkvmerge := exec.LookPath(mkvmerge)
+	if _ttx != nil || _pyftsubset != nil {
+		log.Printf(`Missing dependency: fonttools (need "%s" & "%s").`, ttx, pyftsubset)
+		ec++
+	}
+	if _mkvextract != nil || _mkvmerge != nil {
+		log.Printf(`Missing dependency: mkvtoolnix (need "%s" & "%s").`, mkvextract, mkvmerge)
+		ec++
+	}
+	if ec > 0 {
+		return nil
+	}
+	if _instance == nil {
+		_instance = new(mkvProcessor)
+	}
+	return _instance
+}