/*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2013-present Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* limitations under the License.
*/
-#ifndef FOLLY_FILE_H_
-#define FOLLY_FILE_H_
+#pragma once
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
-#include <unistd.h>
#include <string>
+#include <system_error>
+#include <folly/ExceptionWrapper.h>
+#include <folly/Expected.h>
#include <folly/Portability.h>
#include <folly/Range.h>
+#include <folly/portability/Unistd.h>
namespace folly {
/**
* Creates an empty File object, for late initialization.
*/
- File();
+ File() noexcept;
/**
* Create a File object from an existing file descriptor.
* Takes ownership of the file descriptor if ownsFd is true.
*/
- explicit File(int fd, bool ownsFd = false);
+ explicit File(int fd, bool ownsFd = false) noexcept;
/**
* Open and create a file object. Throws on error.
+ * Owns the file descriptor implicitly.
*/
explicit File(const char* name, int flags = O_RDONLY, mode_t mode = 0666);
explicit File(
const std::string& name, int flags = O_RDONLY, mode_t mode = 0666);
explicit File(StringPiece name, int flags = O_RDONLY, mode_t mode = 0666);
+ /**
+ * All the constructors that are not noexcept can throw std::system_error.
+ * This is a helper method to use folly::Expected to chain a file open event
+ * to something else you want to do with the open fd.
+ */
+ template <typename... Args>
+ static Expected<File, exception_wrapper> makeFile(Args&&... args) noexcept {
+ try {
+ return File(std::forward<Args>(args)...);
+ } catch (const std::system_error& se) {
+ return makeUnexpected(exception_wrapper(std::current_exception(), se));
+ }
+ }
+
~File();
/**
void swap(File& a, File& b);
-
-} // namespace folly
-
-#endif /* FOLLY_FILE_H_ */
+} // namespace folly