Beta of v1.0.3

Author: rhymeswithmogul

CHANGELOG.md

@@ -1,5 +1,10 @@
 # PSTimeMachine Change Log
 
+## Version 1.0.3 (in progress)
+ - If a file is in use and can't be copied, PSTimeMachine will now keep running instead of terminating.
+ - If a copy-only backup is performed, file names will now be written to the log file.
+ - Resolve-Path has replaced -Replace for calculating relative paths.
+
 ## Version 1.0.2 (2019-06-03)
  - Fixed a bug where an initial or -NoHardLinks backup would not show verbose errors when -Verbose was supplied.
  - Fixed a bug where the script would terminate before completion if transcription were not enabled.

PSTimeMachine.ps1

@@ -1,6 +1,6 @@
 <#
 .NOTES
-PSTimeMachine.ps1 - Version 1.0.2
+PSTimeMachine.ps1 - Version 1.0.3-beta6
 (c) 2019 Colin Cogle <colin@colincogle.name>
 
 This program is free software:  you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
@@ -91,16 +91,19 @@ Param(
 	[Switch]$NoStatistics = $false
 )
 
-# Save the old error preference.  It's rude to clobber the user's environment.
+# Save the old error preference and location.  It's rude to clobber the user's environment.
 New-Variable -Option Constant -Name OldErrorActionPreference -Value $ErrorActionPreference
+New-Variable -Option Constant -Name OldLocation -Value (Get-Location)
 $ErrorActionPreference = "Stop"
+Set-Location -Path $SourcePath
 
 # We're going to create a folder to hold the backup, named for the current date and time.
 # Format everything except the year with leading zeroes.
 New-Variable -Option Constant -Name Today      -Value (Get-Date)
 New-Variable -Option Constant -Name FolderName -Value (("{0:yyyy}-{0:MM}-{0:dd}T{0:hh}-{0:mm}-{0:ss}" -f $Today) + ".inProgress")
 
 # Start logging?
+$DoVerboseCopy = $VerbosePreference -eq "Continue"
 If (-Not $NoLogging) {
 	$script:LogFile = (New-TemporaryFile)
 	Start-Transcript -Path (($script:LogFile).Name)
@@ -131,63 +134,69 @@ $bytesCopied = 0
 $bytesTotal  = 0
 
 Try {
-	# Has hardlinking support been disabled?  If so, just do a copy.
-	If ($NoHardLinks) {
-		Write-Verbose "Hard-linking is disabled at user request. Copying all files."
-		Copy-Item -Path (Join-Path -Path $SourcePath "*") -Destination (Join-Path -Path $DestinationPath $FolderName) -Recurse
+	$DoCopyOnlyBackup = $NoHardLinks
+
+	# Look for old backups in the same destination.
+	$PreviousBackups = (Get-ChildItem -Attributes Directory -Path $DestinationPath -Exclude "*.inProgress" -ErrorAction SilentlyContinue `
+							| Where-Object {$_.Name -CMatch "\d{4}-\d{2}-\d{2}T\d{2}-\d{2}-\d{2}(\.inProgress)?"} `
+							| Sort-Object -Descending CreationTime
+						)
+	If ($PreviousBackups.Count -gt 0) {
+		Write-Verbose "Previous backup found.  Doing an incremental backup."
+		$DoCopyOnlyBackup = $false
+		$PreviousBackup = $PreviousBackups[0].Name
 	}
 	Else {
-		# Look for old backups in the same destination.
-		$PreviousBackups = (Get-ChildItem -Attributes Directory -Path $DestinationPath -Exclude "*.inProgress" -ErrorAction SilentlyContinue `
-								| Where-Object {$_.Name -CMatch "\d{4}-\d{2}-\d{2}T\d{2}-\d{2}-\d{2}(\.inProgress)?"} `
-								| Sort-Object -Descending CreationTime
-							)
-		If ($PreviousBackups.Count -eq 0) {
-			If ($FailIfOldBackupsAreMissing) {
-				Throw [System.Management.Automation.ItemNotFoundException] "No previous backups were found. Exiting at user request."
-			}
-			Write-Verbose "No previous backups exist.  Creating an initial backup."
-			
-			$DoVerboseCopy = $VerbosePreference -eq "Continue"
-			Copy-Item -Path (Join-Path -Path $SourcePath "*") -Destination (Join-Path -Path $DestinationPath $FolderName) -Recurse -Verbose:$DoVerboseCopy
+		If ($FailIfOldBackupsAreMissing) {
+			Throw [System.Management.Automation.ItemNotFoundException] "No previous backups were found. Exiting at user request."
 		}
-		Else {
-			# Get the most recent backup name.
-			$PreviousBackup = $PreviousBackups[0].Name
+		Write-Verbose "Previous backups not found.  Doing a copy-only backup."
+		$DoCopyOnlyBackup = $true
+	}
 
-			Get-ChildItem -Path "$SourcePath\" -Recurse -ErrorAction Stop | ForEach-Object {
-				$RelativeSourceItemPath = (($_.FullName) -Replace [regex]::Escape("$((Get-Item $SourcePath).FullName)"),"")
+	Get-ChildItem -Path "$SourcePath\" -Recurse -FollowSymLink | ForEach-Object {
+		$RelativeSourceItemPath = $_.FullName | Resolve-Path -Relative
+		Write-Debug "Analyzing $_"
 
-				# Create directories, but compare files.
-				If ($_.Attributes -CMatch "Directory") {
-					Write-Debug "Creating folder $(Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath)"
-					New-Item -Type Directory -Path (Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath) | Out-Null
+		# Don't copy the log file.
+		If ($_.Name -eq (($script:LogFile).Name)) {
+			Continue
+		}
+
+		# Create directories, but compare files.
+		If ($_.Attributes -CMatch "Directory") {
+			Write-Debug "Creating folder $(Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath)"
+			New-Item -Type Directory -Path (Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath) | Out-Null
+		}
+		Else {
+			# Compare file sizes and dates to determine if something has changed.
+			If (-Not $DoCopyOnlyBackup) {
+				$PreviousCopyOfFile = Get-Item -Path (Join-Path -Path $DestinationPath $PreviousBackup $RelativeSourceItemPath)
+				If (($_.LastWriteTime -eq $PreviousCopyOfFile.LastWriteTime) -And ($_.Length -eq $PreviousCopyOfFile.Length)) {
+					# The file has not changed since the last backup.  Create a hard link.
+					$DestinationHardlink = @{
+						ItemType    = "HardLink"
+						Target      = ($PreviousCopyOfFile.FullName)
+						Path        = ($PreviousCopyOfFile | Split-Path -Parent) -Replace [regex]::Escape($PreviousBackup),$FolderName
+						Name        = ($PreviousCopyOfFile.Name)
+					}
+					Write-Verbose "Linking: $RelativeSourceItemPath"
+					New-Item @DestinationHardlink | Out-Null
 				}
 				Else {
-					# Compare file sizes and dates to determine if something has changed.
-					$PreviousCopyOfFile = Get-Item -Path (Join-Path -Path $DestinationPath $PreviousBackup $RelativeSourceItemPath)
-					If (($_.LastWriteTime -eq $PreviousCopyOfFile.LastWriteTime) -And ($_.Length -eq $PreviousCopyOfFile.Length)) {
-						# The file has not changed since the last backup.  Create a hard link.
-						$DestinationHardlink = @{
-							ItemType    = "HardLink"
-							Target      = ($PreviousCopyOfFile.FullName)
-							Path        = ($PreviousCopyOfFile | Split-Path -Parent) -Replace [regex]::Escape($PreviousBackup),$FolderName
-							Name        = ($PreviousCopyOfFile.Name)
-							ErrorAction = "Stop"
-						}
-						Write-Verbose "Linking: $RelativeSourceItemPath"
-						New-Item @DestinationHardlink | Out-Null
-					}
-					Else {
-						Write-Verbose "Copying: $RelativeSourceItemPath"
-						Copy-Item -Path $_.FullName -Destination (Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath) -ErrorAction Stop
-						$bytesCopied += $_.Length
-					}
-					$bytesTotal  += $_.Length
+					Write-Verbose "Copying: $RelativeSourceItemPath"
+					Copy-Item -Path $_.FullName -Destination (Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath) -Verbose:$DoVerboseCopy
+					$bytesCopied += $_.Length
 				}
+			} Else {
+				Write-Verbose "Copying: $RelativeSourceItemPath"
+				Copy-Item -Path $_.FullName -Destination (Join-Path -Path $DestinationPath $FolderName $RelativeSourceItemPath) -Verbose:$DoVerboseCopy
+				$bytesCopied += $_.Length
 			}
+			$bytesTotal  += $_.Length
 		}
 	}
+
 	Write-Output "Backup completed at $(Get-Date)."
 	Rename-Item -Path (Join-Path -Path $DestinationPath $FolderName) -NewName ($FolderName -CReplace '\.inProgress')
 	If (-Not $NoStatistics -And $bytesTotal -gt 0) {
@@ -202,11 +211,12 @@ Catch {
 Finally {
 	If (-Not $NoLogging) {
 		Write-Verbose "Moving log file to backup destination."
-		Stop-Transcript -ErrorAction SilentlyContinue
+		Stop-Transcript -ErrorAction SilentlyContinue | Out-Null
 		Write-Debug "Moving $($_.FullName) to $(Join-Path -Path $DestinationPath 'PSTimeMachine.log')"
 		Move-Item -Path (($script:LogFile).Name) -Destination (Join-Path -Path $DestinationPath $FolderName "PSTimeMachine.log") -ErrorAction Continue
 	}
 
-	# Restore the user's preferred error action preference.
+	# Restore the user's environment.
 	$ErrorActionPreference = $OldErrorActionPreference
-}
+	Set-Location -Path $OldLocation
+}