2 files changed, 47 insertions, 0 deletions
diff --git a/internal/stats/lock_posix.go b/internal/stats/lock_posix.go
new file mode 100644
index 0000000..2c41d31
--- /dev/null
+++ b/internal/stats/lock_posix.go
@@ -0,0 +1,23 @@
+//go:build !windows
+
+package stats
+
+import (
+	"errors"
+
+	"golang.org/x/sys/unix"
+)
+
+func tryLockFile(fd uintptr) error {
+	if err := unix.Flock(int(fd), unix.LOCK_EX|unix.LOCK_NB); err != nil {
+		if errors.Is(err, unix.EWOULDBLOCK) {
+			return errLockWouldBlock
+		}
+		return err
+	}
+	return nil
+}
+
+func unlockFile(fd uintptr) error {
+	return unix.Flock(int(fd), unix.LOCK_UN)
+}
diff --git a/internal/stats/lock_windows.go b/internal/stats/lock_windows.go
new file mode 100644
index 0000000..2ec5e90
--- /dev/null
+++ b/internal/stats/lock_windows.go
@@ -0,0 +1,24 @@
+//go:build windows
+
+package stats
+
+import (
+	"golang.org/x/sys/windows"
+)
+
+func tryLockFile(fd uintptr) error {
+	var ol windows.Overlapped
+	err := windows.LockFileEx(windows.Handle(fd), windows.LOCKFILE_EXCLUSIVE_LOCK|windows.LOCKFILE_FAIL_IMMEDIATELY, 0, 1, 0, &ol)
+	if err == nil {
+		return nil
+	}
+	if err == windows.ERROR_LOCK_VIOLATION {
+		return errLockWouldBlock
+	}
+	return err
+}
+
+func unlockFile(fd uintptr) error {
+	var ol windows.Overlapped
+	return windows.UnlockFileEx(windows.Handle(fd), 0, 1, 0, &ol)
+}