Prototype of Files service.

services/files/util.h

Index: services/files/util.h
diff --git a/services/files/util.h b/services/files/util.h
new file mode 100644
index 0000000000000000000000000000000000000000..324781dd2c684ce778ad524ee84b0ede42da1a2d
--- /dev/null
+++ b/services/files/util.h
@@ -0,0 +1,55 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef SERVICES_FILES_UTIL_H_
+#define SERVICES_FILES_UTIL_H_
+
+#include "services/files/types.mojom.h"
+
+namespace mojo {
+
+class String;
+
+namespace files {
+
+// Validation functions (typically used to check arguments; they return
+// |ERROR_OK| if valid, else the standard/recommended error for the validation
+// error):
+
+// Checks if |path|, which must be non-null, is (looks like) a valid (relative)
+// path. (On failure, returns |ERROR_INVALID_ARGUMENT| if |path| is not UTF-8,
+// or |ERROR_PERMISSION_DENIED| if it is not relative.)
+Error IsPathValid(const String& path);
+
+// Checks if |whence| is a valid (known) |Whence| value. (On failure, returns
+// |ERROR_UNIMPLEMENTED|.)
+Error IsWhenceValid(Whence whence);
+
+// Checks if |offset| is a valid file offset (from some point); this is
+// implementation-dependent (typically checking if |offset| fits in an |off_t|).
+// (On failure, returns |ERROR_OUT_OF_RANGE|.)
+Error IsOffsetValid(int64_t offset);
+
+// Conversion functions:
+
+// Converts a standard errno value (|E...|) to an |Error| value.
+Error ErrnoToError(int errno_value);
+
+// Converts a |Whence| value to a standard whence value (|SEEK_...|).
+int WhenceToStandardWhence(Whence whence);
+
+// Converts a |Timespec| to a |struct timespec|. If |in| is null, |out->tv_nsec|
+// is set to |UTIME_OMIT|.
+Error TimespecToStandardTimespec(const Timespec* in, struct timespec* out);
+
+// Converts a |TimespecOrNow| to a |struct timespec|. If |in| is null,
+// |out->tv_nsec| is set to |UTIME_OMIT|; if |in->now| is set, |out->tv_nsec| is
+// set to |UTIME_NOW|.
+Error TimespecOrNowToStandardTimespec(const TimespecOrNow* in,
+                                      struct timespec* out);
+
+}  // namespace files
+}  // namespace mojo
+
+#endif  // SERVICES_FILES_UTIL_H_