1 files changed, 33 insertions, 0 deletions
diff --git a/src/file_opener.hh b/src/file_opener.hh
new file mode 100644
index 0000000..7b01b9f
--- /dev/null
+++ b/src/file_opener.hh
@@ -0,0 +1,33 @@
+#ifndef FILE_OPENER_HH
+#define FILE_OPENER_HH
+
+#include "unique_fd.hh"
+
+#include <filesystem>
+#include <functional>
+#include <memory>
+
+class TaskRunner;
+
+class FileOpener {
+public:
+  virtual ~FileOpener() = default;
+
+  // All callbacks are posted to runner. open() and cancel() must be called
+  // on same thread as runner "runs" on.
+  static std::unique_ptr<FileOpener> create(std::shared_ptr<TaskRunner> runner,
+                                            size_t threads = 1);
+
+  // Never returns 0.
+  virtual uint32_t open(std::filesystem::path path,
+                        std::function<void(uint32_t, unique_fd)> callback) = 0;
+
+  virtual void cancel(uint32_t id) = 0;
+
+protected:
+  FileOpener() = default;
+  FileOpener(FileOpener const&) = delete;
+  FileOpener& operator=(FileOpener const&) = delete;
+};
+
+#endif  // FILE_OPENER_HH