zircon/system/ulib/blobfs/include/blobfs/directory.h

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This file contains a directory which contains blobs.

#pragma once

#ifndef __Fuchsia__
#error Fuchsia-only Header
#endif

#include <digest/digest.h>
#include <fbl/algorithm.h>
#include <fbl/ref_ptr.h>
#include <fs/vfs.h>
#include <fs/vnode.h>
#include <fuchsia/blobfs/c/fidl.h>
#include <fuchsia/io/c/fidl.h>

namespace blobfs {

class Blobfs;

using digest::Digest;
using BlockRegion = fuchsia_blobfs_BlockRegion;

// The root directory of blobfs. This directory is a flat container of all blobs in the filesystem.
class Directory final : public fs::Vnode {
public:
    // Constructs the "directory" blob.
    Directory(Blobfs* bs);
    virtual ~Directory();
    DISALLOW_COPY_ASSIGN_AND_MOVE(Directory);

    // Shim to allow GetAllocatedRegions call to blobfs.
    zx_status_t GetAllocatedRegions(fidl_txn_t* txn) const;
private:
    ////////////////
    // fs::Vnode interface.

    zx_status_t GetNodeInfo(uint32_t flags, fuchsia_io_NodeInfo* info) final;
    zx_status_t ValidateFlags(uint32_t flags) final;
    zx_status_t Readdir(fs::vdircookie_t* cookie, void* dirents, size_t len,
                        size_t* out_actual) final;
    zx_status_t Read(void* data, size_t len, size_t off, size_t* out_actual) final;
    zx_status_t Write(const void* data, size_t len, size_t offset,
                      size_t* out_actual) final;
    zx_status_t Append(const void* data, size_t len, size_t* out_end,
                       size_t* out_actual) final;
    zx_status_t Lookup(fbl::RefPtr<fs::Vnode>* out, fbl::StringPiece name) final;
    zx_status_t Getattr(vnattr_t* a) final;
    zx_status_t Create(fbl::RefPtr<fs::Vnode>* out, fbl::StringPiece name,
                       uint32_t mode) final;
    zx_status_t QueryFilesystem(fuchsia_io_FilesystemInfo* out) final;
    zx_status_t GetDevicePath(size_t buffer_len, char* out_name, size_t* out_len) final;
    zx_status_t Unlink(fbl::StringPiece name, bool must_be_dir) final;
    void Sync(SyncCallback closure) final;
    zx_status_t Serve(fs::Vfs* vfs, zx::channel channel, uint32_t flags) final;
    bool IsDirectory() const final { return true; }

    ////////////////
    // Other methods.

    BlobCache& Cache();

    Blobfs* const blobfs_;
};

} // namespace blobfs