Prototype of Files service.

services/file_manager/util.cc

+// 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.
+
+#include "services/file_manager/util.h"
+
+#include <errno.h>
+
+#include "base/logging.h"
+#include "base/strings/string_util.h"
+#include "mojo/public/cpp/bindings/string.h"
+
+namespace mojo {
+namespace files {
+
+Error IsPathValid(const String& path) {
+  DCHECK(!path.is_null());
+  if (!base::IsStringUTF8(path.get()))
+    return ERROR_INVALID_ARGUMENT;
+  if (path.size() > 0 && path[0] == '/')
+    return ERROR_PERMISSION_DENIED;
+  return ERROR_OK;
+}
+
+Error IsWhenceValid(Whence whence) {
+  return (whence == WHENCE_FROM_CURRENT || whence == WHENCE_FROM_START ||
+          whence == WHENCE_FROM_END)
+             ? ERROR_OK
+             : ERROR_UNIMPLEMENTED;
+}
+
+Error IsOffsetValid(int64_t offset) {
+  return (offset >= std::numeric_limits<off_t>::min() &&
+          offset <= std::numeric_limits<off_t>::max())
+             ? ERROR_OK
+             : ERROR_OUT_OF_RANGE;
+}
+
+Error ErrnoToError(int errno_value) {
+  // TODO(vtl)
+  return ERROR_UNKNOWN;
+}
+
+int WhenceToStandardWhence(Whence whence) {
+  DCHECK_EQ(IsWhenceValid(whence), ERROR_OK);
+  switch (whence) {
+    case WHENCE_FROM_CURRENT:
+      return SEEK_CUR;
+    case WHENCE_FROM_START:
+      return SEEK_SET;
+    case WHENCE_FROM_END:
+      return SEEK_END;
+  }
+  NOTREACHED();
+  return 0;
+}
+
+}  // namespace files
+}  // namespace mojo