Carbon

2.0.0

Functions/ConvertTo-ProviderAccessControlRights.ps1

# Copyright 2012 Aaron Jensen
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

function ConvertTo-ProviderAccessControlRights
{
    <#
    .SYNOPSIS
    Converts strings into the appropriate access control rights for a PowerShell provider (e.g. FileSystemRights or RegistryRights).
 
    .DESCRIPTION
    This is an internal Carbon function, so you're not getting anything more than the synopsis.
 
    .EXAMPLE
    ConvertTo-ProviderAccessControlRights -ProviderName 'FileSystem' -InputObject 'Read','Write'
 
    Demonstrates how to convert `Read` and `Write` into a `System.Security.AccessControl.FileSystemRights` value.
    #>
    [CmdletBinding()]
    param(
        [Parameter(Mandatory=$true)]
        [ValidateSet('FileSystem','Registry','CryptoKey')]
        [string]
        # The provider name.
        $ProviderName,

        [Parameter(Mandatory=$true,ValueFromPipeline=$true)]
        [string[]]
        # The values to convert.
        $InputObject
    )

    begin
    {
        Set-StrictMode -Version 'Latest'

        Use-CallerPreference -Cmdlet $PSCmdlet -Session $ExecutionContext.SessionState

        $rights = 0
        $rightTypeName = 'Security.AccessControl.{0}Rights' -f $ProviderName
        $foundInvalidRight = $false
    }

    process
    {
        $InputObject | ForEach-Object { 
            $right = ($_ -as $rightTypeName)
            if( -not $right )
            {
                $allowedValues = [Enum]::GetNames($rightTypeName)
                Write-Error ("System.Security.AccessControl.{0}Rights value '{1}' not found. Must be one of: {2}." -f $providerName,$_,($allowedValues -join ' '))
                $foundInvalidRight = $true
                return
            }
            $rights = $rights -bor $right
        }
    }

    end
    {
        if( $foundInvalidRight )
        {
            return $null
        }
        else
        {
            $rights
        }
    }
}