Method: Etch::Client#save_history

Defined in:

lib/etch/client.rb

#save_history(file) ⇒ Object

This subroutine maintains a revision history for the file in @historybase

# File 'lib/etch/client.rb', line 1785

def save_history(file)
  histdir = File.join(@historybase, "#{file}.HISTORY")
  current = File.join(histdir, 'current')
  
  # Migrate old RCS history
  if File.file?(histdir) && File.directory?(File.join(File.dirname(histdir), 'RCS'))
    if !@dryrun
      puts "Migrating old RCS history to new format"
      rcsmax = nil
      IO.popen("rlog #{histdir}") do |pipe|
        pipe.each do |line|
          if line =~ /^head: 1.(.*)/
            rcsmax = $1.to_i
            break
          end
        end
      end
      if !rcsmax
        raise "Failed to parse RCS history rlog output"
      end
      tmphistdir = tempdir(histdir)
      1.upto(rcsmax) do |rcsrev|
        rcsrevcontents = `co -q -p1.#{rcsrev} #{histdir}`
        # rcsrev-1 because RCS starts revisions at 1.1 and we start files
        # at 0000
        File.open(File.join(tmphistdir, sprintf('%04d', rcsrev-1)), 'w') do |rcsrevfile|
          rcsrevfile.write(rcsrevcontents)
        end
      end
      FileUtils.copy(histdir, File.join(tmphistdir, 'current'))
      File.delete(histdir)
      File.rename(tmphistdir, histdir)
    end
  end

  # Make sure the directory tree for this file exists in the
  # directory we save history in.
  if !File.exist?(histdir)
    puts "Making history directory #{histdir}"
    FileUtils.mkpath(histdir) if (!@dryrun)
  end
  
  # If the history log doesn't exist and we didn't just create the original
  # backup then that indicates that the original backup was made previously
  # but the history log was not started at the same time. There are a
  # variety of reasons why this might be the case (the most likely is that
  # the original was saved manually by someone) but whatever the reason is
  # we want to use the original backup to start the history log before
  # updating the history log with the current file.
  if !File.exist?(File.join(histdir, 'current')) && !@first_update[file]
    origpath = save_orig(file)
    if File.file?(origpath) && !File.symlink?(origpath)
      puts "Starting history log with saved original file:  " +
           "#{origpath} -> #{current}"
      FileUtils.copy(origpath, current) if (!@dryrun)
    else
      puts "Starting history log with 'ls -ld' output for " +
           "saved original file:  #{origpath} -> #{current}"
      system("ls -ld #{origpath} > #{current} 2>&1") if (!@dryrun)
    end
    set_history_permissions(file)
  end
  
  # Make temporary copy of file
  newcurrent = current+'.new'
  if File.file?(file) && !File.symlink?(file)
    puts "Updating history log:  #{file} -> #{current}"
    if File.exist?(newcurrent)
      remove_file(newcurrent)
    end
    FileUtils.copy(file, newcurrent) if (!@dryrun)
  else
    puts "Updating history log with 'ls -ld' output:  #{file} -> #{current}"
    system("ls -ld #{file} > #{newcurrent} 2>&1") if (!@dryrun)
  end
  
  # Roll current to next XXXX if current != XXXX
  if File.exist?(current)
    nextfile = '0000'
    maxfile = Dir.entries(histdir).select{|e|e=~/^\d+/}.max
    if maxfile
      if compare_file_contents(File.join(histdir, maxfile), File.read(current))
        nextfile = nil
      else
        nextfile = sprintf('%04d', maxfile.to_i + 1)
      end
    end
    if nextfile
      File.rename(current, File.join(histdir, nextfile)) if (!@dryrun)
    end
  end
  
  # Move temporary copy to current
  File.rename(current+'.new', current) if (!@dryrun)
  
  set_history_permissions(file)
end