Add basic compilation functionality

src/bpmlib/tarball.go

@@ -5,6 +5,8 @@ import (
 	"errors"
 	"io"
 	"os"
+	"path"
+	"strings"
 )
 
 type tarballFileReader struct {
@@ -41,3 +43,65 @@ func readTarballContent(tarballPath, fileToExtract string) (*tarballFileReader,
 
 	return nil, errors.New("could not file in tarball")
 }
+
+func extractTarballDirectory(tarballPath, directoryToExtract, workingDirectory string) (err error) {
+	file, err := os.Open(tarballPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	tr := tar.NewReader(file)
+	for {
+		header, err := tr.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		if strings.HasPrefix(header.Name, directoryToExtract+"/") {
+			// Skip directory to extract
+			if strings.TrimRight(header.Name, "/") == workingDirectory {
+				continue
+			}
+
+			// Trim directory name from header name
+			header.Name = strings.TrimPrefix(header.Name, directoryToExtract+"/")
+			outputPath := path.Join(workingDirectory, header.Name)
+
+			switch header.Typeflag {
+			case tar.TypeDir:
+				// Create directory
+				err := os.MkdirAll(outputPath, 0755)
+				if err != nil {
+					return err
+				}
+			case tar.TypeReg:
+				// Create file and set permissions
+				file, err = os.Create(outputPath)
+				if err != nil {
+					return err
+				}
+				err := file.Chmod(header.FileInfo().Mode())
+				if err != nil {
+					return err
+				}
+
+				// Copy data to file
+				_, err = io.Copy(file, tr)
+				if err != nil {
+					return err
+				}
+
+				// Close file
+				file.Close()
+			default:
+				continue
+			}
+		}
+	}
+
+	return nil
+}