Reformatted.

This involved fixing the literal TAB characters, changing the quotes,
and similar non-functional edits.

5 files changed, 220 insertions, 246 deletions

diff --git a/byteback-backup b/byteback-backup
index 202323d..ac9165a 100755
--- a/byteback-backup
+++ b/byteback-backup
@@ -8,7 +8,7 @@
 
 require 'resolv'
 
-$LOAD_PATH.unshift("/usr/lib/byteback")
+$LOAD_PATH.unshift('/usr/lib/byteback')
 
 require 'trollop'
 require 'byteback/util'
@@ -16,50 +16,47 @@ require 'byteback/log'
 include Byteback::Util
 include Byteback::Log
 
+ME = $PROGRAM_NAME.split('/').last
 
-ME = $0.split("/").last
-
-opts = Trollop::options do
-
+opts = Trollop.options do
   banner "#{ME}: Back up this system to a byteback-enabled server\n "
 
-  opt :destination, "Backup destination (i.e. user@host:/path)",
-      :type => :string
+  opt :destination, 'Backup destination (i.e. user@host:/path)',
+      type: :string
 
-  opt :source, "Source paths",
-      :type => :strings,
-      :default => ["/"]
+  opt :source, 'Source paths',
+      type: :strings,
+      default: ['/']
 
-  opt :exclude, "Paths to exclude",
-      :type => :strings,
-      :short => "x"
+  opt :exclude, 'Paths to exclude',
+      type: :strings,
+      short: 'x'
 
-  opt :verbose, "Show debugging messages"
+  opt :verbose, 'Show debugging messages'
 
-  opt :retry_number, "Number of retries on error",
-      :type => :integer,
-      :default => 3
+  opt :retry_number, 'Number of retries on error',
+      type: :integer,
+      default: 3
 
-  opt :retry_delay, "Number of seconds between retries after an error",
-      :type => :integer,
-      :default => 300
+  opt :retry_delay, 'Number of seconds between retries after an error',
+      type: :integer,
+      default: 300
 
-  opt :ssh_key, "SSH key filename",
-      :type => :string,
-      :default => "/etc/byteback/key",
-      :short => "k"
+  opt :ssh_key, 'SSH key filename',
+      type: :string,
+      default: '/etc/byteback/key',
+      short: 'k'
 
-  opt :help, "Show this message",
-      :short => "h"
+  opt :help, 'Show this message',
+      short: 'h'
 
   banner "\nAdditional excludes can be specified using /etc/byteback/rsync_filter, which is an rsync filter file.  See the rsync man page for information on how this works.\n"
-
 end
 
-lock_out_other_processes("byteback-backup")
+lock_out_other_processes('byteback-backup')
 
 @ssh_key = opts[:ssh_key]
-@verbose = opts[:verbose] ? "--verbose" : nil
+@verbose = opts[:verbose] ? '--verbose' : nil
 @sources = opts[:source] if opts[:source]
 @excludes = opts[:exclude] if opts[:exclude]
 @destination = opts[:destination]
@@ -67,33 +64,33 @@ lock_out_other_processes("byteback-backup")
 @retry_delay = opts[:retry_delay]
 
 # Read the default destination
-if File.exists?("/etc/byteback/destination")
-  @destination = File.read("/etc/byteback/destination").chomp
+if File.exist?('/etc/byteback/destination')
+  @destination = File.read('/etc/byteback/destination').chomp
 end
 
 # Set the default SSH key
-if File.exists?("/etc/byteback/key")
-  @ssh_key = "/etc/byteback/key"
+if File.exist?('/etc/byteback/key')
+  @ssh_key = '/etc/byteback/key'
 end
 
 #
 # Check our destination
 #
 if @destination =~ /^(?:(.+)@)?([^@:]+):(.+)?$/
-  @destination_user, @destination_host, @destination_path = [$1, $2, $3]
+  @destination_user, @destination_host, @destination_path = [Regexp.last_match(1), Regexp.last_match(2), Regexp.last_match(3)]
 else
-  fatal("Destination must be a remote path, e.g. ssh@host.com:/store/backups")
+  fatal('Destination must be a remote path, e.g. ssh@host.com:/store/backups')
 end
 
 #
 # Validate & normalise source directories
 #
-@sources = ["/"] if @sources.nil?
+@sources = ['/'] if @sources.nil?
 
-fatal("No sources specified") if @sources.empty?
+fatal('No sources specified') if @sources.empty?
 
 @sources = @sources.map do |s|
-  s = s.gsub(/\/+/,"/")
+  s = s.gsub(/\/+/, '/')
   fatal("Can't read directory #{s}") unless File.readable?(s)
   s
 end
@@ -119,36 +116,36 @@ if @excludes.nil?
   )
 
   COMMON_JUNK = %w(
-     /swap.file
-     /tmp
-     /var/backups/localhost
-     /var/cache/apt/archives
-     /var/lib/php5
-     /var/tmp
+    /swap.file
+    /tmp
+    /var/backups/localhost
+    /var/cache/apt/archives
+    /var/lib/php5
+    /var/tmp
   )
 
-  MOUNT_HEADINGS = %w( spec file vfstype mntops freq passno ).
-    map(&:to_sym)
+  MOUNT_HEADINGS = %w( spec file vfstype mntops freq passno )
+                   .map(&:to_sym)
 
-  mounts = File.read("/proc/mounts").split("\n").map do |line|
-    Hash[MOUNT_HEADINGS.zip(line.split(" "))]
+  mounts = File.read('/proc/mounts').split("\n").map do |line|
+    Hash[MOUNT_HEADINGS.zip(line.split(' '))]
   end
 
   @excludes =
 
-    mounts.
-      select { |m| !PROBABLY_LOCAL.include?(m[:vfstype]) }.
-      map { |m| m[:file] } +
+    mounts
+    .select { |m| !PROBABLY_LOCAL.include?(m[:vfstype]) }
+    .map { |m| m[:file] } +
 
-    COMMON_JUNK.select { |f| File.exists?(f) }
+    COMMON_JUNK.select { |f| File.exist?(f) }
 
 end
 
 @excludes = @excludes.map do |e|
-  e.gsub(/\/+/,"/")
+  e.gsub(/\/+/, '/')
 end
 
-fatal("Must suply --destination or put it into /etc/bytebackup/destination") unless @destination
+fatal('Must suply --destination or put it into /etc/bytebackup/destination') unless @destination
 
 #
 # Test ssh connection is good before we start
@@ -156,25 +153,25 @@ fatal("Must suply --destination or put it into /etc/bytebackup/destination") unl
 fatal("Could not read ssh key #{@ssh_key}") unless File.readable?(@ssh_key)
 
 def ssh(*ssh_args)
-  args = ["ssh",
-    "-o", "BatchMode=yes",
-    "-o", "ConnectionAttempts=5",
-    "-o", "ConnectTimeout=30",
-    "-o", "ServerAliveInterval=60",
-    "-o", "TCPKeepAlive=yes",
-    "-x", "-a",
-    "-i", @ssh_key,
-    "-l", @destination_user,
-    @destination_host
-  ] +
-  ssh_args.
-  map { |a| a ? a : "" }
+  args = ['ssh',
+          '-o', 'BatchMode=yes',
+          '-o', 'ConnectionAttempts=5',
+          '-o', 'ConnectTimeout=30',
+          '-o', 'ServerAliveInterval=60',
+          '-o', 'TCPKeepAlive=yes',
+          '-x', '-a',
+          '-i', @ssh_key,
+          '-l', @destination_user,
+          @destination_host
+         ] +
+         ssh_args
+         .map { |a| a ? a : '' }
 
   log_system(*args)
 end
 
 fatal("Could not connect to #{@destination}") unless
-  ssh("byteback-receive", "--ping", @verbose) == 0
+  ssh('byteback-receive', '--ping', @verbose) == 0
 
 #
 # Call rsync to copy certain sources, returns exit status (see man rsync)
@@ -192,32 +189,32 @@ def rsync(*sources)
   #
   args = %w( rsync --archive --numeric-ids --delete-delay --inplace --relative --timeout 43200 )
 
-  args += [ "--rsh", "ssh -o BatchMode=yes -x -a -i #{@ssh_key} -l #{@destination_user}"]
-  args << "--verbose" if @verbose
-  args += @excludes.map { |x| ["--exclude", x] }.flatten
+  args += ['--rsh', "ssh -o BatchMode=yes -x -a -i #{@ssh_key} -l #{@destination_user}"]
+  args << '--verbose' if @verbose
+  args += @excludes.map { |x| ['--exclude', x] }.flatten
 
   #
   # Add in the rsync excludes and sources files, if present.
   #
-  if File.exists?("/etc/byteback/excludes")
-      args += ["--exclude-from", "/etc/byteback/excludes"]
+  if File.exist?('/etc/byteback/excludes')
+    args += ['--exclude-from', '/etc/byteback/excludes']
   end
 
   #
   # Add in an rsync_filter if required.
   #
-  if File.exists?("/etc/byteback/rsync_filter")
-      args += ["--filter", "merge /etc/byteback/rsync_filter"]
+  if File.exist?('/etc/byteback/rsync_filter')
+    args += ['--filter', 'merge /etc/byteback/rsync_filter']
   end
 
   #
   # To add extra rsync flags, a file can be used.  This can have flags all on one line, or one per line.
   #
-  if File.exists?("/etc/byteback/rsync_flags")
-    args += File.readlines("/etc/byteback/rsync_flags").map(&:chomp)
+  if File.exist?('/etc/byteback/rsync_flags')
+    args += File.readlines('/etc/byteback/rsync_flags').map(&:chomp)
   end
 
-  args += [ "--rsync-path", "rsync --fake-super"]
+  args += ['--rsync-path', 'rsync --fake-super']
 
   args += sources
   args << @destination
@@ -231,16 +228,16 @@ end
 # on some hosts the backup process never finishes.
 #
 RSYNC_EXIT_STATUSES_TO_ACCEPT   = [0, 24]
-RSYNC_EXIT_STATUSES_TO_RETRY_ON = [10,11,20,21,22,23,30]
+RSYNC_EXIT_STATUSES_TO_RETRY_ON = [10, 11, 20, 21, 22, 23, 30]
 
 # Run the file copy, retrying if necessary
 #
 loop do
   status = rsync(*@sources)
 
-  if RSYNC_EXIT_STATUSES_TO_ACCEPT.any?{|s| s === status}
+  if RSYNC_EXIT_STATUSES_TO_ACCEPT.any? { |s| s === status }
     break
-  elsif RSYNC_EXIT_STATUSES_TO_RETRY_ON.any?{|s| s === status}
+  elsif RSYNC_EXIT_STATUSES_TO_RETRY_ON.any? { |s| s === status }
 
     warn "rsync exited with status #{status}"
 
@@ -250,18 +247,18 @@ loop do
       sleep @retry_delay
       redo
     else
-      fatal("Maximum number of rsync retries reached")
+      fatal('Maximum number of rsync retries reached')
     end
   else
     fatal("Fatal rsync error occurred (#{status})")
   end
 end
 
-info("Backup completed, requesting snapshot")
+info('Backup completed, requesting snapshot')
 
 # Mark the backup as done on the other end
 #
-fatal("Backup could not be marked complete") unless
-  ssh("byteback-receive", "--complete", @verbose) == 0
+fatal('Backup could not be marked complete') unless
+  ssh('byteback-receive', '--complete', @verbose) == 0
 
-info("Finished")
+info('Finished')
diff --git a/byteback-prune b/byteback-prune
index 28ef2bf..d005289 100755
--- a/byteback-prune
+++ b/byteback-prune
@@ -4,7 +4,7 @@
 # backups (whether by age, or importance).
 #
 
-$LOAD_PATH.unshift("/usr/lib/byteback")
+$LOAD_PATH.unshift('/usr/lib/byteback')
 
 require 'trollop'
 require 'byteback'
@@ -13,30 +13,28 @@ include Byteback
 include Byteback::Log
 include Byteback::Util
 
-opts = Trollop::options do
+opts = Trollop.options do
+  banner "Prune old backup directories to ensure there's enough space"
 
-    banner "Prune old backup directories to ensure there's enough space"
+  opt :minpercent, 'Start prune when disk has less than this %age free',
+      type: :integer,
+      default: 5
 
-    opt :minpercent, "Start prune when disk has less than this %age free",
-        :type => :integer,
-        :default => 5
+  opt :maxpercent, 'Stop prune when disk has more than this %age free',
+      type: :integer,
+      default: 10
 
-    opt :maxpercent, "Stop prune when disk has more than this %age free",
-        :type => :integer,
-        :default => 10
+  opt :list, 'List backups in pruning order, no other action'
 
-    opt :list, "List backups in pruning order, no other action"
+  opt :prune, 'Prune the next backup if necessary'
 
-    opt :prune, "Prune the next backup if necessary"
+  opt :prune_force, 'Prune the next backup regardless'
 
-    opt :prune_force, "Prune the next backup regardless"
-
-    opt :order, "Order backups by 'age' or 'importance'",
-    	:type => :string,
-    	:default => "importance"
-
-    opt :verbose, "Show debugging messages"
+  opt :order, "Order backups by 'age' or 'importance'",
+      type: :string,
+      default: 'importance'
 
+  opt :verbose, 'Show debugging messages'
 end
 
 @order = opts[:order]
@@ -49,7 +47,7 @@ end
 
 @do_prune = true if @do_prune_force
 
-fatal("Must specify one of --prune or --list") unless
+fatal('Must specify one of --prune or --list') unless
   (@do_prune || @do_list) &&
   !(@do_prune && @do_list)
 
@@ -57,24 +55,24 @@ fatal("Must specify --order as 'age' or 'importance'") unless
   @order == 'age' || @order == 'importance'
 
 if BackupDirectory.all.empty?
-	fatal("No backup directories found, need to run byteback-snapshot")
+  fatal('No backup directories found, need to run byteback-snapshot')
 end
 
-lock_out_other_processes("byteback-prune")
+lock_out_other_processes('byteback-prune')
 
 @df_history = DiskFreeHistory.new(ENV['HOME'])
 begin
-	@df_history.new_reading!
+  @df_history.new_reading!
 rescue Errno::ENOSPC
-	if @do_list
-		warn("Couldn't write disk history file due to lack of space, ignoring")
-	else
-		warn("Couldn't write disk history file due to lack of space, going to --prune-force")
-		@do_prune = @do_prune_force = true
-	end
+  if @do_list
+    warn("Couldn't write disk history file due to lack of space, ignoring")
+  else
+    warn("Couldn't write disk history file due to lack of space, going to --prune-force")
+    @do_prune = @do_prune_force = true
+  end
 rescue => anything_else
-	error("Couldn't record disk history of #{@df_history.mountpoint} in #{@df_history.history_file}, installation problem?")
-	raise
+  error("Couldn't record disk history of #{@df_history.mountpoint} in #{@df_history.history_file}, installation problem?")
+  raise
 end
 
 gradient_30m = @df_history.gradient(1800)
@@ -85,57 +83,57 @@ gradient_30m = @df_history.gradient(1800)
 PRUNING_FLAG = "#{ENV['HOME']}/.byteback.pruning"
 
 if @do_prune_force
-	info("Forcing prune")
-elsif @free <= @minpercent && !File.exists?(PRUNING_FLAG)
-	info("Starting prune #{@free}% -> #{@maxpercent} free")
-	File.write(PRUNING_FLAG,"")
-elsif @free >= @maxpercent && File.exists?(PRUNING_FLAG)
-	info("Stopping prune, reached #{@free}% free")
-	File.unlink(PRUNING_FLAG)
-elsif File.exists?(PRUNING_FLAG)
-	info("Continuing prune #{@free}% -> #{@maxpercent}, gradient = #{gradient_30m}")
+  info('Forcing prune')
+elsif @free <= @minpercent && !File.exist?(PRUNING_FLAG)
+  info("Starting prune #{@free}% -> #{@maxpercent} free")
+  File.write(PRUNING_FLAG, '')
+elsif @free >= @maxpercent && File.exist?(PRUNING_FLAG)
+  info("Stopping prune, reached #{@free}% free")
+  File.unlink(PRUNING_FLAG)
+elsif File.exist?(PRUNING_FLAG)
+  info("Continuing prune #{@free}% -> #{@maxpercent}, gradient = #{gradient_30m}")
 end
 
 debug("Disc free #{@free}%, 30m gradient = #{gradient_30m}")
 
 def snapshots_in_order
-	list = BackupDirectory.all_snapshots
-	if @order == 'importance'
-		Snapshot.sort_by_importance(list)
-	elsif @order == 'age'
-		list.sort.reverse
-	else
-		raise ArgumentError.new("Unknown snapshot sort method #{method}")
-	end
+  list = BackupDirectory.all_snapshots
+  if @order == 'importance'
+    Snapshot.sort_by_importance(list)
+  elsif @order == 'age'
+    list.sort.reverse
+  else
+    fail ArgumentError.new("Unknown snapshot sort method #{method}")
+  end
 end
 
 snapshots = snapshots_in_order
 
 if @do_list
-	print "Backups by #{@order}:\n"
-	snapshots.each_with_index do |snapshot, index|
-		print "#{sprintf('% 3d',index)}: #{snapshot.path}\n"
-	end
+  print "Backups by #{@order}:\n"
+  snapshots.each_with_index do |snapshot, index|
+    print "#{sprintf('% 3d', index)}: #{snapshot.path}\n"
+  end
 end
 
 # Don't do anything if we've not got two hours of readings
 #
-if !@do_prune_force
-    if @df_history.list.last.time - @df_history.list.first.time < 1800
-	    warn("Not enough disc space history to make a decision")
-	    exit 0
-    end
+unless @do_prune_force
+  if @df_history.list.last.time - @df_history.list.first.time < 1800
+    warn('Not enough disc space history to make a decision')
+    exit 0
+  end
 end
 
 exit 0 unless
-  (@do_prune && File.exists?(PRUNING_FLAG)) ||
+  (@do_prune && File.exist?(PRUNING_FLAG)) ||
   @do_prune_force
 
 exit 0 unless @do_prune_force || gradient_30m == 0
 
 if snapshots.empty?
-	error("No snapshots to delete, is there enough disc space?")
-	exit 1
+  error('No snapshots to delete, is there enough disc space?')
+  exit 1
 end
 
 info("Deleting #{snapshots.last.path}")
diff --git a/byteback-receive b/byteback-receive
index 23282db..4b949c2 100755
--- a/byteback-receive
+++ b/byteback-receive
@@ -9,26 +9,25 @@ require 'trollop'
 require 'byteback'
 include Byteback::Log
 
-
 if ENV['SSH_ORIGINAL_COMMAND']
-	ARGV.concat(ENV['SSH_ORIGINAL_COMMAND'].split(" "))
+  ARGV.concat(ENV['SSH_ORIGINAL_COMMAND'].split(' '))
 end
 
 byteback_host = ENV['BYTEBACK_HOST']
-fatal("BYTEBACK_HOST environment not set") unless byteback_host
+fatal('BYTEBACK_HOST environment not set') unless byteback_host
 
-byteback_root = ENV['HOME'] + "/" + ENV["BYTEBACK_HOST"]
+byteback_root = ENV['HOME'] + '/' + ENV['BYTEBACK_HOST']
 fatal("#{byteback_root} does not exist") unless File.directory?(byteback_root)
 
 #
 #  Force restores to be limited to the hostname we're connecting form
 #
-if ( ARGV[0] == 'restore' )
+if (ARGV[0] == 'restore')
   ARGV[0] = 'rsync'
   a = []
   ARGV.each do |tmp|
-    if ( tmp =~ /^\/(.*)/ )
-      tmp = "#{byteback_host}/#{$1.dup}"
+    if  tmp =~ /^\/(.*)/
+      tmp = "#{byteback_host}/#{Regexp.last_match(1).dup}"
     end
     a.push(tmp)
   end
@@ -37,27 +36,27 @@ elsif ARGV[0] == 'rsync'
   ARGV[-1] = "#{byteback_root}/current"
   exec(*ARGV)
 elsif ARGV[0] == 'byteback-snapshot'
-  ARGV.concat(["--root", "#{byteback_root}"])
+  ARGV.concat(['--root', "#{byteback_root}"])
   exec(*ARGV)
 end
 
-opts = Trollop::options do
-	opt :verbose, "Print diagnostics"
-	opt :ping, "Check connection parameters and exit"
-	opt :list, "Show backed up files matching the given pattern", :type => :string
-	opt :restore, "Perform a restoration operation", :type => :string
-	opt :complete, "Mark current backup as complete"
+opts = Trollop.options do
+  opt :verbose, 'Print diagnostics'
+  opt :ping, 'Check connection parameters and exit'
+  opt :list, 'Show backed up files matching the given pattern', type: :string
+  opt :restore, 'Perform a restoration operation', type: :string
+  opt :complete, 'Mark current backup as complete'
 end
 
-error("Please only choose one mode") if opts[:ping] && opts[:complete]
+error('Please only choose one mode') if opts[:ping] && opts[:complete]
 if opts[:complete]
-	system("byteback-snapshot", "--root", byteback_root)
+  system('byteback-snapshot', '--root', byteback_root)
 elsif opts[:list]
-	system( "cd #{byteback_root} && find . -print | grep #{opts[:list]}" )
-	exit(0 )
+  system("cd #{byteback_root} && find . -print | grep #{opts[:list]}")
+  exit(0)
 elsif opts[:ping]
-	exit 0
+  exit 0
 else
-	STDERR.print "byteback-receive failed\n"
-	exit 9
+  STDERR.print "byteback-receive failed\n"
+  exit 9
 end
diff --git a/byteback-restore b/byteback-restore
index 9a6f3f0..48eea9a 100755
--- a/byteback-restore
+++ b/byteback-restore
@@ -3,50 +3,44 @@
 # Restore a file from the most recent backup, from the remote host.
 #
 
-$LOAD_PATH.unshift("/usr/lib/byteback")
-$LOAD_PATH.unshift("./lib/")
+$LOAD_PATH.unshift('/usr/lib/byteback')
+$LOAD_PATH.unshift('./lib/')
 
 require 'trollop'
 
-
 #
 #  Show an error message and abort.
 #
-def fatal( str )
-  STDERR.puts( str )
+def fatal(str)
+  STDERR.puts(str)
   exit(1)
 end
 
-
-
 #
 #  Run a remote command.
 #
 def ssh(*ssh_args)
-  args = ["ssh",
-    "-o", "BatchMode=yes",
-    "-o", "ConnectionAttempts=5",
-    "-o", "ConnectTimeout=30",
-    "-o", "ServerAliveInterval=60",
-    "-o", "TCPKeepAlive=yes",
-    "-x", "-a",
-    "-i", @ssh_key,
-    "-l", @destination_user,
-    @destination_host
-  ] +
-  ssh_args.
-  map { |a| a ? a : "" }
+  args = ['ssh',
+          '-o', 'BatchMode=yes',
+          '-o', 'ConnectionAttempts=5',
+          '-o', 'ConnectTimeout=30',
+          '-o', 'ServerAliveInterval=60',
+          '-o', 'TCPKeepAlive=yes',
+          '-x', '-a',
+          '-i', @ssh_key,
+          '-l', @destination_user,
+          @destination_host
+         ] +
+         ssh_args
+         .map { |a| a ? a : '' }
 
   system(*args)
 end
 
-
-
-def list_files( pattern )
-  ssh("byteback-receive", "--list", pattern )
+def list_files(pattern)
+  ssh('byteback-receive', '--list', pattern)
 end
 
-
 #
 #  We cannot use plain 'rsync' here because the receiver command will
 # see that, and rewrite our arguments.
@@ -55,89 +49,77 @@ end
 # do that by setting "rsync-path" to point to the receiver program.
 #
 #
-def restore_file( path, revision )
+def restore_file(path, revision)
   cmd = %w( rsync )
-  cmd += [ "--rsh", "ssh -o BatchMode=yes -x -a -i /etc/byteback/key -l byteback" ]
-  cmd += [ "--rsync-path", "restore --fake-super" ]
-  cmd += [ "-aApzrX",  "--numeric-ids" ]
-  cmd += [ "#{@destination_host}:/#{revision}/#{path}", "." ]
+  cmd += ['--rsh', 'ssh -o BatchMode=yes -x -a -i /etc/byteback/key -l byteback']
+  cmd += ['--rsync-path', 'restore --fake-super']
+  cmd += ['-aApzrX',  '--numeric-ids']
+  cmd += ["#{@destination_host}:/#{revision}/#{path}", '.']
   system(*cmd)
-
 end
 
-
-
-
-
 #
 #  Parse our command-line arguments
 #
-opts = Trollop::options do
-
+opts = Trollop.options do
   banner "byteback-restore: Restore a file\n "
 
-  opt :file, "The file to restore",
-      :type => :string
+  opt :file, 'The file to restore',
+      type: :string
 
   opt :revision, "The version of the file to restore - default is 'latest'",
-      :type => :string
+      type: :string
 
-  opt :destination, "Backup destination (i.e. user@host:/path)",
-      :type => :string
-
-  opt :ssh_key, "SSH key filename",
-      :type => :string,
-      :default => "/etc/byteback/key",
-      :short => "k"
+  opt :destination, 'Backup destination (i.e. user@host:/path)',
+      type: :string
 
+  opt :ssh_key, 'SSH key filename',
+      type: :string,
+      default: '/etc/byteback/key',
+      short: 'k'
 end
 
-
-
 #
 #  Setup default destination and key.
 #
-@destination = File.read("/etc/byteback/destination").chomp if
-  File.exists?("/etc/byteback/destination")
-@ssh_key = "/etc/byteback/key" if File.exists?("/etc/byteback/key")
+@destination = File.read('/etc/byteback/destination').chomp if
+  File.exist?('/etc/byteback/destination')
+@ssh_key = '/etc/byteback/key' if File.exist?('/etc/byteback/key')
 
 #
 #  Allow the command-line to override them.
 #
-@ssh_key = opts[:ssh_key] unless( opts[:ssh_key].nil?)
-@destination = opts[:destination] unless ( opts[:destination].nil? )
-
+@ssh_key = opts[:ssh_key] unless  opts[:ssh_key].nil?
+@destination = opts[:destination] unless  opts[:destination].nil?
 
 #
 # Check our destination is well-formed
 #
 if @destination =~ /^(?:(.+)@)?([^@:]+):(.+)?$/
-  @destination_user, @destination_host, @destination_path = [$1, $2, $3]
+  @destination_user, @destination_host, @destination_path = [Regexp.last_match(1), Regexp.last_match(2), Regexp.last_match(3)]
 else
-  fatal("Destination must be a remote path, e.g. ssh@host.com:/store/backups")
+  fatal('Destination must be a remote path, e.g. ssh@host.com:/store/backups')
 end
 
-
 #
 #  If the user didn't specify a file then we're not restoring anything,
 # and we should abort.
 #
-if ( opts[:file].nil? )
-  fatal("You must specify a file to restore" )
+if  opts[:file].nil?
+  fatal('You must specify a file to restore')
 end
 
 #
 #  If the user specified a file, but not a revision, then we list
 # the available revisions.
 #
-if ( opts[:revision].nil? )
-  list_files( opts[:file] )
+if  opts[:revision].nil?
+  list_files(opts[:file])
   exit(0)
 end
 
-
 #
 #  Restore a file
 #
-restore_file( opts[:file], opts[:revision] )
+restore_file(opts[:file], opts[:revision])
 exit(0)
diff --git a/byteback-snapshot b/byteback-snapshot
index 6249d3d..fc9aab3 100755
--- a/byteback-snapshot
+++ b/byteback-snapshot
@@ -4,39 +4,37 @@
 # using btrfs subvolume commands.
 #
 
-$LOAD_PATH.unshift("/usr/lib/byteback")
+$LOAD_PATH.unshift('/usr/lib/byteback')
 
 require 'trollop'
 require 'byteback'
 include Byteback
 include Byteback::Log
 
-opts = Trollop::options do
+opts = Trollop.options do
+  opt :root, 'Backups directory (must be a btrfs subvolume)',
+      type: :string
 
-    opt :root, "Backups directory (must be a btrfs subvolume)",
-    	:type => :string
-
-    opt :snapshot, "(ignored for compatibility)"
-
-    opt :verbose, "Print diagnostics"
+  opt :snapshot, '(ignored for compatibility)'
 
+  opt :verbose, 'Print diagnostics'
 end
 
 @root = opts[:root]
 @verbose = opts[:verbose]
 
-fatal("--root not readable") unless File.directory?("#{@root}")
+fatal('--root not readable') unless File.directory?("#{@root}")
 
 @backups = BackupDirectory.new(@root)
 snapshots = @backups.snapshots
 
-if !snapshots.empty?
-	last_snapshot_time = snapshots.last.time
-	fatal("Last snapshot was less than six hours ago") unless
-		!last_snapshot_time ||
-		Time.now - last_snapshot_time >= 6*60*60 # FIXME: make configurable
+unless snapshots.empty?
+  last_snapshot_time = snapshots.last.time
+  fatal('Last snapshot was less than six hours ago') unless
+    !last_snapshot_time ||
+    Time.now - last_snapshot_time >= 6 * 60 * 60 # FIXME: make configurable
 end
 
-info "Making new snapshot"
+info 'Making new snapshot'
 @backups.new_snapshot!
-info "Finished"
+info 'Finished'