Private/Get-FirebirdODSVersion.ps1
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<#
.SYNOPSIS Gets the ODS (On-Disk Structure) version of a Firebird database file. .DESCRIPTION Reads the header of a Firebird database file and returns its ODS major and minor version as a version object. .PARAMETER Database Path to the Firebird database file to inspect. Must exist. .EXAMPLE Get-FirebirdODSVersion -Database '/data/mydb.fdb' Returns the ODS version of the specified database file. .OUTPUTS System.Version. The ODS version in the format Major.Minor. #> function Get-FirebirdODSVersion { [CmdletBinding()] param( [Parameter(Mandatory)] [ValidateScript({ Test-Path $_.Path }, ErrorMessage = 'The Database must exist.')] [FirebirdDatabase]$Database ) # Read the first 80 bytes of the database file Write-VerboseMark "Reading header from file '$Database'..." $bytes = Get-Content -Path $Database.Path -AsByteStream -TotalCount 80 if ($bytes.Length -lt 80) { throw "File '$($Database.Path)' is not a valid Firebird database." } # Source: https://www.firebirdsql.org/file/documentation/html/en/firebirddocs/firebirdinternals/firebird-internals.html # hdr_ods_version # Two bytes, unsigned. Bytes 0x12 and 0x13 on the page. The ODS major version for the database. # The format of this word is the ODS major version ANDed with the Firebird flag of 0x8000. $odsVersion = [BitConverter]::ToUInt16($bytes, 0x12) -band 0x7FFF Write-VerboseMark "odsVersion = $($odsVersion)" # hdr_ods_minor_original # Two bytes, unsigned. Bytes 0x40 and 0x41 on the page. The ODS minor version when the database was originally created. $odsMinorOriginal = [BitConverter]::ToUInt16($bytes, 0x40) Write-VerboseMark "odsMinorOriginal = $($odsMinorOriginal)" # Return as [version] object return [version]::new($odsVersion, $odsMinorOriginal) } |