hg2svn.php

<?php
  require_once( dirname(__FILE__) . '/functions.php' );


  # Parameter checking!
  switch( strtolower(@$_SERVER['argv'][1]) )
  {
  case 'init':
    if ( $_SERVER['argc'] < 4 ) {
      usage();
    }
    else {
      define('CACHING_DIR', $temporary_path);
      init();
    }
    break;

  case 'sync':
    if ( $_SERVER['argc'] < 3 ) {
      usage();
    }
    else {
      sync();
    }
    break;
    
  default:
    usage();
    break;
  }
  exit(0);






  function init() {
    $from_hg_repo = $_SERVER['argv'][2];
    $to_svn_repo  = $_SERVER['argv'][3];

    # Step 1: check revprops of SVN to see if we already inited() it.
    $properties = get_revision_properties($to_svn_repo);

    if ( in_array(SVNPROP_TEMPDIR, $properties) ) {
      cout("SVN repository seems to be already initialized! Use sync instead.", VERBOSE_ERROR);
      exit(1);
    }

    # Step 2: create temporary structure
    $checkout_directory = create_and_check_directory_structure();
    $tmpdir_hg          = $checkout_directory.'_hg'; 
    $tmpdir_svn         = $checkout_directory.'_svn'; 

    # Step 3: clone hg & svn
    safe_exec('hg clone '.escapeshellarg($from_hg_repo).' '.escapeshellarg($tmpdir_hg));
    safe_exec('svn checkout '.escapeshellarg($to_svn_repo).' '.escapeshellarg($tmpdir_svn));

    # Step 4: set revprops on SVN target
    safe_exec('svn propset '.escapeshellarg(SVNPROP_TEMPDIR).' --revprop -r 0 '.escapeshellarg($checkout_directory).' '.escapeshellarg($to_svn_repo));
    safe_exec('svn propset '.escapeshellarg(SVNPROP_HG_REPO).' --revprop -r 0 '.escapeshellarg($from_hg_repo)      .' '.escapeshellarg($to_svn_repo));

    cout("Successfully initialized. Ready for sync.");
  }

  # TODO: symlinks
  function sync() {
    $to_svn_repo = $_SERVER['argv'][2];
    $to_svn_repo_split = parse_url($to_svn_repo);

    # Step 1: check revprops of SVN to see if we already inited() it.
    $properties = get_revision_properties($to_svn_repo);
    if ( !in_array(SVNPROP_TEMPDIR, $properties) ) {
      cout("SVN repository doesn't seem to be initialized! Use init instead.", VERBOSE_ERROR);
      exit(1);
    }
    $tmp_dir      = safe_exec('svn propget '.escapeshellarg(SVNPROP_TEMPDIR).' --revprop -r 0 '.escapeshellarg($to_svn_repo));
    $from_hg_repo = safe_exec('svn propget '.escapeshellarg(SVNPROP_HG_REPO).' --revprop -r 0 '.escapeshellarg($to_svn_repo));
    $last_hg_rev  = safe_exec('svn propget '.escapeshellarg(SVNPROP_HG_REV) .' --revprop -r 0 '.escapeshellarg($to_svn_repo));
    if ( $last_hg_rev === '' ) { // First revision!
      $last_hg_rev = -1;
    }

    define('CACHING_DIR', dirname($tmp_dir));

    # Step 2: get tmp directory
    create_and_check_directory_structure($tmp_dir);
    $tmpdir_hg  = $tmp_dir.'_hg'; 
    $tmpdir_svn = $tmp_dir.'_svn'; 
    unset($tmp_dir);

    # Step 3: check for cached hg/svn repositories
    if ( !is_dir($tmpdir_hg.'/.hg') ) {
      if ( !completely_remove($tmpdir_hg) ) {
        cout('Cannot remove hg tmpdir!', VERBOSE_ERROR);
        exit(1);
      }
      safe_exec('hg clone '.escapeshellarg($from_hg_repo).' '.escapeshellarg($tmpdir_hg));
    }

    if ( !is_dir($tmpdir_svn.'/.svn') ) {
      if ( !completely_remove($tmpdir_svn) ) {
        cout('Cannot remove svn tmpdir!', VERBOSE_ERROR);
        exit(1);
      }
      safe_exec('svn checkout '.escapeshellarg($to_svn_repo).' '.escapeshellarg($tmpdir_svn));
    }

    # Step 4: updating hg (no need to update svn as that should be read only to the outside world!)
    cout("Ensuring HG repo is up to date before sync.", VERBOSE_INFO);
    chdir($tmpdir_hg);
    safe_exec('hg pull');
    safe_exec('hg up');
    chdir($tmpdir_svn);
    safe_exec('svn revert . -R');
    $out = array_diff(array_map('trim', explode("\n", safe_exec('svn status'))), array(''));
    foreach( $out as $line ) {
      $l = array_map('trim', explode(' ', $line));
      if ( array_shift($l) != '?' ) {
        cout("Weird SVN status encountered!", VERBOSE_ERROR);
        exit(1);
      }

      $filename = null;
      while ( count($l) > 0 ) {
        if ( file_exists(implode(' ', $l)) ) {
          $filename = implode(' ', $l);
          break;
        }
        else {
          array_shift($l);
        }
      }

      if ( !is_null($filename) ) {
        force_remove_item($filename);
      }
    }

    # Step 5: check which is the revision I need to stop
    chdir($tmpdir_hg);
    $stop_rev = get_tip_revision();
    if ( $stop_rev === false ) {
      cout("No tip revision found?!", VERBOSE_ERROR);
      exit(1);
    }


    # Step 6: Check which are branches/merged revisions:
    $merged_revisions = array();
    $branched_revisions = array();
    for ( $current_rev = $stop_rev; $current_rev >= $last_hg_rev; --$current_rev ) {
#      $log = parse_hg_log_message($current_rev);
      investigate_branch($current_rev, $merged_revisions, $branched_revisions);
/*
      if ( isset($log['parent']) ) {
        # If the revision we're checking is already in the 'branched_revisions'
        if ( in_array($current_rev, $branched_revisions) ) {
          # --> Consider everything in here a branched revision!
          if ( is_array($log['parent']) ) {
            foreach( $log['parent'] as $parent ) {
              add_to_array_without_duplicates($branched_revisions, $parent);
            }
          }
          else { // A normal string
            add_to_array_without_duplicates($branched_revisions, $log['parent']);
          }
        }
        # Ok, check if we have multiple parents!
        else if ( is_array($log['parent']) ) {
          $merged_revisions[] = $current_rev;
          array_shift($log['parent']); // Chat with Davis King: assume the first one is the "main" branch, all other parents are pulled from other sources (remote, branches, ...).
          foreach( $log['parent'] as $parent ) {
            add_to_array_without_duplicates($branched_revisions, $parent);
          }
        }
      }
*/
    }
    print_r($merged_revisions);
    print_r($branched_revisions);
    die();


    # Step 7... The final looping...
    $prev_rev = $last_hg_rev;
    $tempfile = tempnam('/tmp', 'hg2svn');
    $tempfile_esc = escapeshellarg($tempfile);

    for ($current_rev = $last_hg_rev + 1; $current_rev <= $stop_rev; $current_rev++) {
      if ( defined('STOP_AT_REVISION') && ($current_rev >= STOP_AT_REVISION) ) {
        cout("Reached target revision (".STOP_AT_REVISION."), stopping...", VERBOSE_NORMAL);
        break;
      }
      # Sub 1: fetch the changes between the 2 revisions
      chdir($tmpdir_hg);
      cout("Fetching Mercurial revision {$current_rev}/{$stop_rev}");

      $log  = parse_hg_log_message($current_rev);

      $hg_log_msg       = $log['description'];
      $hg_log_changeset = explode(':', $log['changeset']);
      $hg_log_changeset = array_shift($hg_log_changeset);
      $hg_log_user      = $log['user'];
      $hg_log_date      = gmstrftime('%Y-%m-%dT%H:%M:%S.000000Z', strtotime($log['date']));

      if ( isset($log['parent']) && is_array($log['parent']) ) {
        // Merged revision --> Skipping
        safe_exec('svn propset '.escapeshellarg(SVNPROP_HG_REV).' --revprop -r 0 '.escapeshellarg($current_rev).' '.escapeshellarg($to_svn_repo));
        continue;
      }

      cout("Current log message: '{$hg_log_msg}'", VERBOSE_INFO);

      $diff = parse_hg_diff($current_rev);

      # Sub 2: apply them to SVN
      chdir($tmpdir_svn);
      cout('- Applying differences');
      foreach( $diff as $patch ) {
        switch( $patch['action'] ) {
        case 'add':
        case 'update': # TODO: what with binary updates?
          patch_file($patch);
          break;

        case 'delete':
          remove_item($patch['file1']);
          break;

        case 'change_chmod':
          if ( strlen($patch['patch']) > 0 ) {
            throw new Exception("**TODO** Fix this here!");
          }
          chmod($patch['file1'], $patch['chmod']);
          if ( !is_executable($patch['file1']) ) {
            safe_exec('svn propdel svn:executable '.escapeshellarg($patch['file1']));
          }
          else {
            safe_exec('svn propset svn:executable yes '.escapeshellarg($patch['file1']));
          }
          break;

        case 'symlink':
          create_dir_in_svn(dirname($patch['file1']));
          if ( IS_WINDOWS ) {
            file_put_contents($patch['file1'], "link ".$patch['file2']);
            safe_exec('svn add --parents '.escapeshellarg($patch['file1']));
            safe_exec('svn propset svn:special yes '.escapeshellarg($patch['file1']));
          }
          else {
            symlink($patch['file2'], $patch['file1']);
            safe_exec('svn add --parents '.escapeshellarg($patch['file1']));
          }
          break;

        case 'copy':
          create_dir_in_svn(dirname($patch['to']));
          safe_exec('svn copy '.escapeshellarg($patch['from']).' '.escapeshellarg($patch['to']));
          patch_file($patch);
          break;

        case 'rename':
          create_dir_in_svn(dirname($patch['to']));
          safe_exec('svn move '.escapeshellarg($patch['from']).' '.escapeshellarg($patch['to']));
          remove_dirtree_if_empty(dirname($patch['from']));
          patch_file($patch);
          break;

        default:
          throw new Exception("Unimplemented action '{$patch['action']}'");
          break;
        }
      }

      # Sub 3: apply svn:ignore if needed (see if .hgignore was added/updated/removed)
      # TODO: take previous .hgignores & see if they are changed...
      #       parse if needed & apply svn:ignore properties accordingly.

      # Sub 4: commit
      cout('- Committing');
      $commit_command = 'svn commit . --trust-server-cert --non-interactive --no-auth-cache --username '.escapeshellarg($to_svn_repo_split['user']). ' --password '.escapeshellarg($to_svn_repo_split['pass']).' -m '.escapeshellarg($hg_log_msg);
      $out = safe_exec($commit_command);
      if ( preg_match('|Committed revision ([0-9]+)\.|iUms', $out, $m) > 0 ) {
        $svn_revision = $m[1];
      }
      else {
        $svn_revision = null;
      }

      if ( !is_null($svn_revision) ) {
        # Remove empty subdirectories from the tree
        foreach( $diff as $patch ) {
          if ( $patch['action'] == 'delete' ) {
            remove_file_step2($patch['file1']);
          }
          else if ( $patch['action'] == 'rename' ) {
            remove_file_step2($patch['from']);
          }
        }

        # Sub 5: adjust dates/author and the likes
        safe_exec('svn propset '.escapeshellarg('svn:author').' --revprop -r '.escapeshellarg($svn_revision).' '.escapeshellarg($hg_log_user).' '.escapeshellarg($to_svn_repo));
        safe_exec('svn propset '.escapeshellarg('svn:date')  .' --revprop -r '.escapeshellarg($svn_revision).' '.escapeshellarg($hg_log_date).' '.escapeshellarg($to_svn_repo));
      }

      # Sub 6: setting last fetched svn property
      safe_exec('svn propset '.escapeshellarg(SVNPROP_HG_REV).' --revprop -r 0 '.escapeshellarg($current_rev).' '.escapeshellarg($to_svn_repo));
    }

    cout("Sync finished (for now).", VERBOSE_NORMAL);
  }