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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef DOM_QUOTA_DIRECTORYMETADATA_H_
#define DOM_QUOTA_DIRECTORYMETADATA_H_
#include <cstdint>
enum class nsresult : uint32_t;
class nsIBinaryInputStream;
class nsIBinaryOutputStream;
class nsIFile;
namespace mozilla {
template <typename V, typename E>
class Result;
}
namespace mozilla::dom::quota {
struct OriginStateMetadata;
/**
* Directory Metadata File Format (.metadata-v2)
*
* The metadata file is a binary file containing metadata information for an
* origin directory. It consists of a header and several additional fields,
* some of which are maintained only for backward compatibility.
*
* Header (OriginStateMetadata):
* - int64_t mLastAccessTime
* The last access time of the origin in microseconds since the epoch.
* - bool mPersisted
* True if the origin is marked as persisted and should survive origin
* eviction.
* - uint32_t flags
* A bitfield of DirectoryMetadataFlags used to store boolean state flags.
* This field currently maps only to mAccessed. The defined flags are:
* - Initialized: Always set when writing metadata; indicates that this
* field contains valid flag bits. Older files written before this
* flag was introduced will have this field set to zero.
* - Accessed: Indicates whether the origin has been accessed by a quota
* client. This maps directly to the mAccessed field in memory.
*
* If the Initialized flag is not set, the flags field is considered
* invalid and mAccessed is conservatively set to true to ensure a full
* initialization scan.
* - int32_t mLastMaintenanceDate
* The last maintenance date of the origin in days since the epoch.
*
* Legacy fields (still written and read for backward compatibility, but no
* longer used):
* - nsCString mSuffix
* Originally used for origin attributes. Still written to preserve
* compatibility.
* - nsCString mGroup
* Originally used for quota group. Still written to preserve
* compatibility.
*
* Storage fields:
* - nsCString mStorageOrigin
* Storage origin string (actively used for reconstructing the principal).
*
* Legacy fields (continued):
* - bool mIsPrivate
* Flag originally used for private browsing contexts or apps. Still
* written.
*
* Validation check:
* - After reading all expected fields, any additional data (even a single
* 32-bit value) is treated as an error.
*
* Notes:
* - OriginStateMetadata is loaded first and interpreted independently. This
* allows fast and safe updates to the metadata header on disk without
* rewriting the full file.
* - The header is intentionally designed to contain only fixed-size fields.
* This allows updating the header in-place without creating a temporary
* file.
*/
Result<OriginStateMetadata, nsresult> ReadDirectoryMetadataHeader(
nsIBinaryInputStream& aStream);
nsresult WriteDirectoryMetadataHeader(
nsIBinaryOutputStream& aStream,
const OriginStateMetadata& aOriginStateMetadata);
Result<OriginStateMetadata, nsresult> LoadDirectoryMetadataHeader(
nsIFile& aDirectory);
nsresult SaveDirectoryMetadataHeader(
nsIFile& aDirectory, const OriginStateMetadata& aOriginStateMetadata);
} // namespace mozilla::dom::quota
#endif // DOM_QUOTA_NOTIFYUTILS_H_
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