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// 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.
// TODO(vtl): notes to self:
// - file offsets, file positions, and file sizes are int64 (though positions
// and sizes must always be non-negative)
// - buffer size parameters (for read/write) are uint32
module filesystem.mojom;
import "components/filesystem/public/interfaces/types.mojom";
import "mojo/common/file.mojom";
// TODO(vtl): Write comments.
interface File {
// Flushes/closes this file; no operations may be performed on this file after
// this. Note that any error code is strictly informational -- the close may
// not be retried.
[Sync]
Close() => (FileError err);
// Reads (at most) |num_bytes_to_read| from the location specified by
// |offset|/|whence|. On success, |bytes_read| is set to the data read.
// TODO(vtl): Define/clarify behavior when less than |num_bytes_to_read| bytes
// are read.
// TODO(vtl): Clarify when (for what values of |offset|/|whence|) this
// modifies the file position. Or maybe there should be a flag?
[Sync]
Read(uint32 num_bytes_to_read, int64 offset, Whence whence)
=> (FileError error, array<uint8>? bytes_read);
// Writes |bytes_to_write| to the location specified by |offset|/|whence|.
// TODO(vtl): Clarify behavior when |num_bytes_written| is less than the size
// of |bytes_to_write|.
[Sync]
Write(array<uint8> bytes_to_write, int64 offset, Whence whence)
=> (FileError error, uint32 num_bytes_written);
// Gets the current file position. On success, |position| is the current
// offset (in bytes) from the beginning of the file).
[Sync]
Tell() => (FileError error, int64 position);
// Sets the current file position to that specified by |offset|/|whence|. On
// success, |position| is the offset (in bytes) from the beginning of the
// file.
[Sync]
Seek(int64 offset, Whence whence) => (FileError error, int64 position);
// Gets information about this file. On success, |file_information| is
// non-null and will contain this information.
[Sync]
Stat() => (FileError error, FileInformation? file_information);
// Truncates this file to the size specified by |size| (in bytes).
[Sync]
Truncate(int64 size) => (FileError error);
// Updates this file's atime and/or mtime to the time specified by |atime| (or
// |mtime|, respectively), which may also indicate "now". If |atime| or
// |mtime| is null, then the corresponding time is not modified.
[Sync]
Touch(TimespecOrNow? atime, TimespecOrNow? mtime) => (FileError error);
// Creates a new |File| instance, which shares the same "file description".
// I.e., the access mode, etc. (as specified to |Directory::OpenFile()| by the
// |open_flags| argument) as well as file position.
[Sync]
Dup(File& file) => (FileError error);
// Syncs data to disk.
[Sync]
Flush() => (FileError error);
// Attempts to take an exclusive write lock on the file. This both takes a
// native OS file lock (so that non-chrome, non-mojo processes can't write to
// this file).
[Sync]
Lock() => (FileError error);
// Unlocks a previously locked file.
[Sync]
Unlock() => (FileError error);
// Returns a handle to the file for raw access.
[Sync]
AsHandle() => (FileError error, mojo.common.mojom.File? file_handle);
};
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