1 files changed, 42 insertions, 0 deletions
diff --git a/internal/darwin/version.go b/internal/darwin/version.go
new file mode 100644
index 000000000..a4bd591a8
--- /dev/null
+++ b/internal/darwin/version.go
@@ -0,0 +1,42 @@
+package darwin
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync"
+
+	"gitlab.com/gitlab-org/gitaly/v16/internal/command"
+)
+
+var (
+	majorVersion     int
+	majorVersionOnce sync.Once
+)
+
+// MajorVersion returns a major number of the MacOS version.
+func MajorVersion() int {
+	majorVersionOnce.Do(func() {
+		var buffer strings.Builder
+		ctx, cancel := context.WithCancel(context.Background())
+		defer cancel()
+		cmd, err := command.New(ctx, []string{"sw_vers", "-productVersion"}, command.WithStdout(&buffer))
+		if err != nil {
+			panic(fmt.Errorf("executing sw_vers command: %w", err))
+		}
+		if err := cmd.Wait(); err != nil {
+			panic(fmt.Errorf("waiting for sw_vers command completion: %w", err))
+		}
+		parts := strings.Split(buffer.String(), ".")
+		if len(parts) > 0 {
+			version, err := strconv.ParseFloat(parts[0], 32)
+			if err != nil {
+				panic(fmt.Errorf("parse mac version: %w", err))
+			}
+			majorVersion = int(version)
+		}
+	})
+
+	return majorVersion
+}