feat: initial commit

pkg/wails3kit/updates/platform/apply.go

@@ -0,0 +1,119 @@
+package platform
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strconv"
+
+	"github.com/Eriyc/rules_wails/pkg/wails3kit/updates"
+)
+
+type restorePoint struct {
+	path     string
+	backup   string
+	hadPrior bool
+}
+
+func applyBundle(request helperRequest) error {
+	backupDir, err := os.MkdirTemp("", "wails3kit-backup-*")
+	if err != nil {
+		return err
+	}
+
+	restores := make([]restorePoint, 0, len(request.Bundle.Files))
+	for _, file := range request.Bundle.Files {
+		source := filepath.Join(request.StagedPath, filepath.FromSlash(file.Path))
+		target := filepath.Join(request.InstallRoot, filepath.FromSlash(file.Path))
+		modeValue, err := strconv.ParseUint(file.Mode, 8, 32)
+		if err != nil {
+			rollback(restores)
+			return err
+		}
+		mode := os.FileMode(modeValue)
+
+		restore, err := backupTarget(backupDir, target)
+		if err != nil {
+			rollback(restores)
+			return err
+		}
+		restores = append(restores, restore)
+
+		if err := os.MkdirAll(filepath.Dir(target), 0o755); err != nil {
+			rollback(restores)
+			return err
+		}
+		if err := os.RemoveAll(target); err != nil {
+			rollback(restores)
+			return err
+		}
+		if err := copyFile(source, target, mode); err != nil {
+			rollback(restores)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func backupTarget(backupDir string, target string) (restorePoint, error) {
+	point := restorePoint{path: target}
+	info, err := os.Stat(target)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return point, nil
+		}
+		return point, err
+	}
+	if info.IsDir() {
+		return point, fmt.Errorf("%w: target %s is a directory", updates.ErrInvalidArtifact, target)
+	}
+
+	backupPath := filepath.Join(backupDir, filepath.Base(target))
+	if err := copyFile(target, backupPath, info.Mode()); err != nil {
+		return point, err
+	}
+	point.hadPrior = true
+	point.backup = backupPath
+	return point, nil
+}
+
+func rollback(restores []restorePoint) {
+	for index := len(restores) - 1; index >= 0; index-- {
+		restore := restores[index]
+		if restore.hadPrior {
+			info, err := os.Stat(restore.backup)
+			if err == nil {
+				_ = os.RemoveAll(restore.path)
+				_ = os.MkdirAll(filepath.Dir(restore.path), 0o755)
+				_ = copyFile(restore.backup, restore.path, info.Mode())
+			}
+			continue
+		}
+		_ = os.RemoveAll(restore.path)
+	}
+}
+
+func copyFile(sourcePath string, destinationPath string, mode os.FileMode) error {
+	source, err := os.Open(sourcePath)
+	if err != nil {
+		return err
+	}
+	defer source.Close()
+
+	return writeFile(destinationPath, source, mode)
+}
+
+func writeFile(path string, source io.Reader, mode os.FileMode) error {
+	file, err := os.Create(path)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	if _, err := io.Copy(file, source); err != nil {
+		return err
+	}
+	return file.Chmod(mode)
+}