openpkg-packages/monotone/monotone.patch.rse

  This is the RSE patchset for the Monotone VCS.

  The patchset is entirely enclosed in...
  
    #if defined(RSE) /* <tag> */
    [...]
    #endif

  ...and this way can be clearly distinguished. The <tag> corresponds
  the following major changes it includes:

  o environment-variables:
    This adds the two environment variables MTN_DBFILE and MTN_KEYDIR as
    defaults for the (bootstrapping) mtn(1) command line options --db
    and --keydir. This allows you to provide values for them without
    having to pass the options all the time.

  o alt-book-keeping-root:
    This allows mtn(1) to accept an alternative book-keeping directory.
    The default still is "_MTN", but alternatively one can rename this
    to ".mtn". If one sets the environment variable "MTN_BKROOT" one can
    change ".mtn" to an arbitrary sub-directory name and additionally
    even force its use on workspace creation operations.

  o cosmetics-netsync:
    This is just a small cosmetics change. It reduces the annoying
    "doing anonymous pull; use -kKEYNAME if you need authentication" to
    just "doing anonymous pull" as mtn(1) doesn't have to teach people.
    That's for what the documentation is for.
    
  o cosmetics-stat:
    The workspace top-level directory is shown as "" instead of nothing.

  o cosmetics-diff-and-log:
    This cosmetically "improves" the output of "mtn diff" and "mtn
    log". For "mtn diff" The output of "mtn diff" now uses a separator
    line consisting of 67 (instead of 60) "=" characters to align
    with cvs(1)'s well known output. Additionally, two new command
    line options for "mtn diff" allow one to disable some outputs:
    "--no-show-header" disables the output of the redundant "#..."
    header lines at the top of the output and "--no-show-separator"
    disables the output of the separator line at all. The output of "mtn
    log" is improved by aligning the single-line certificate values and
    by indenting the file change information by just 4 instead of 8
    characters.

  o diff-index:
    This adds "Index:" lines to the output of "mtn diff" in order to
    align with the "svn diff" and "cvs diff" outputs. This also helps
    patch(1) to clearly identify the file to patch.

  o extra-commands:
    This adds "mtn fuse", "mtn conflicts", "mtn revision" and "mtn base"
    commands. They are all simple but convenient Lua wrappers.

  o dot-mtn-message:
    Support a ".mtn-message" file in the root-directory as a template
    for the commit messages.
    
                                       Ralf S. Engelschall
                                       rse@engelschall.com
                                       www.engelschall.com

Index: app_state.cc
--- app_state.cc	6be9949e433ff6166fd030b34d8eb2d3e18c10b6
+++ app_state.cc	ce1cdaffff8c14261ab0a22a16571a0737532bbb
@@ -138,13 +138,24 @@ app_state::create_workspace(system_path 
   go_to_workspace(new_dir);
   mark_std_paths_used();
 
+#if defined(RSE) /* alt-book-keeping-root */
+  N(!(directory_exists(bookkeeping_root) || directory_exists(alt_bookkeeping_root)),
+    F("monotone bookkeeping directory '%s' or '%s' already exists in '%s'")
+    % bookkeeping_root % alt_bookkeeping_root % new_dir);
+#else
   N(!directory_exists(bookkeeping_root),
     F("monotone bookkeeping directory '%s' already exists in '%s'")
     % bookkeeping_root % new_dir);
+#endif
 
   L(FL("creating bookkeeping directory '%s' for workspace in '%s'")
     % bookkeeping_root % new_dir);
 
+#if defined(RSE) /* alt-book-keeping-root */
+  if (getenv("MTN_BKROOT") != NULL)
+    mkdir_p(bookkeeping_path(getenv("MTN_BKROOT")));
+  else
+#endif
   mkdir_p(bookkeeping_root);
 
   make_branch_sticky();
Index: cmd_diff_log.cc
--- cmd_diff_log.cc	baea6a3047420da7d1cff17f2669f973e0643e56
+++ cmd_diff_log.cc	f17665eb2b1be7eaef00380fef3e6c170cd1c152
@@ -96,6 +96,27 @@ print_indented_set(ostream & os,
                    set<file_path> const & s,
                    size_t max_cols)
 {
+#if defined(RSE) /* cosmetics-diff-and-log */
+  size_t cols = 4;
+  os << "    ";
+  for (set<file_path>::const_iterator i = s.begin();
+       i != s.end(); i++)
+    {
+      const string str = lexical_cast<string>(*i);
+      if (cols > 4 && cols + str.size() + 1 >= max_cols)
+        {
+          cols = 4;
+          os << "\n    ";
+        }
+      else if (cols > 4) {
+        os << ' ';
+        cols += 1;
+      }
+      os << str;
+      cols += str.size();
+    }
+  os << '\n';
+#else
   size_t cols = 8;
   os << "       ";
   for (set<file_path>::const_iterator i = s.begin();
@@ -113,6 +134,7 @@ print_indented_set(ostream & os,
       cols += str.size() + 1;
     }
   os << '\n';
+#endif
 }
 
 void
@@ -131,7 +153,11 @@ changes_summary::print(ostream & os, siz
       for (map<file_path, file_path>::const_iterator
            i = cs.nodes_renamed.begin();
            i != cs.nodes_renamed.end(); i++)
+#if defined(RSE) /* cosmetics-diff-and-log */
+        os << "    " << i->first
+#else
         os << "        " << i->first
+#endif
            << " to " << i->second << '\n';
     }
 
@@ -232,8 +258,13 @@ dump_diffs(cset const & cs,
            set<file_path> const & paths,
            bool limit_paths = false)
 {
+#if defined(RSE) /* cosmetics-diff-and-log */
+  // 67 is somewhat arbitrary (CVS uses this), but less than 80
+  string patch_sep = string(67, '=');
+#else
   // 60 is somewhat arbitrary, but less than 80
   string patch_sep = string(60, '=');
+#endif
 
   for (map<file_path, file_id>::const_iterator
          i = cs.files_added.begin();
@@ -242,6 +273,9 @@ dump_diffs(cset const & cs,
       if (limit_paths && paths.find(i->first) == paths.end())
         continue;
 
+#if defined(RSE) /* cosmetics-diff-and-log */
+      if (!app.opts.no_show_separator)
+#endif
       output << patch_sep << '\n';
       data unpacked;
       vector<string> lines;
@@ -288,6 +322,9 @@ dump_diffs(cset const & cs,
       file_data f_old;
       data data_old, data_new;
 
+#if defined(RSE) /* cosmetics-diff-and-log */
+      if (!app.opts.no_show_separator)
+#endif
       output << patch_sep << '\n';
 
       app.db.get_file_version(delta_entry_src(i), f_old);
@@ -503,6 +540,9 @@ CMD(diff, "diff", "di", CMD_REF(informat
   data summary;
   write_cset(included, summary);
 
+#if defined(RSE) /* cosmetics-diff-and-log */
+  if (!app.opts.no_show_header) {
+#endif
   vector<string> lines;
   split_into_lines(summary(), lines);
   cout << "#\n";
@@ -518,6 +558,9 @@ CMD(diff, "diff", "di", CMD_REF(informat
       cout << "# " << _("no changes") << '\n';
     }
   cout << "#\n";
+#if defined(RSE) /* cosmetics-diff-and-log */
+  }
+#endif
 
   if (app.opts.diff_format == external_diff)
     {
@@ -881,7 +924,11 @@ CMD(log, "log", "", CMD_REF(informative)
           else
             {
               out << string(65, '-') << '\n';
+#if defined(RSE) /* cosmetics-diff-and-log */
+              out << "Revision:  " << rid << '\n';
+#else
               out << "Revision: " << rid << '\n';
+#endif
 
               changes_summary csum;
 
@@ -896,12 +943,21 @@ CMD(log, "log", "", CMD_REF(informative)
 
               for (set<revision_id>::const_iterator anc = ancestors.begin();
                    anc != ancestors.end(); ++anc)
+#if defined(RSE) /* cosmetics-diff-and-log */
+                out << "Ancestor:  " << *anc << '\n';
+
+              log_certs(out, app, rid, author_name, "Author:    ", false);
+              log_certs(out, app, rid, date_name,   "Date:      ", false);
+              log_certs(out, app, rid, branch_name, "Branch:    ", false);
+              log_certs(out, app, rid, tag_name,    "Tag:       ", false);
+#else
                 out << "Ancestor: " << *anc << '\n';
 
               log_certs(out, app, rid, author_name, "Author: ", false);
               log_certs(out, app, rid, date_name,   "Date: ",   false);
               log_certs(out, app, rid, branch_name, "Branch: ", false);
               log_certs(out, app, rid, tag_name,    "Tag: ",    false);
+#endif
 
               if (!app.opts.no_files && !csum.cs.empty())
                 {
@@ -911,7 +967,11 @@ CMD(log, "log", "", CMD_REF(informative)
                 }
 
               log_certs(out, app, rid, changelog_name, "ChangeLog: ", true);
+#if defined(RSE) /* cosmetics-diff-and-log */
+              log_certs(out, app, rid, comment_name,   "Comments:  ", true);
+#else
               log_certs(out, app, rid, comment_name,   "Comments: ",  true);
+#endif
             }
 
           if (app.opts.diffs)
Index: cmd_netsync.cc
--- cmd_netsync.cc	92bc91c7137e339e086b3ab761f1aed5df203143
+++ cmd_netsync.cc	06dde80e2d7cc9bf8c9413a3df408dbb4cf36110
@@ -179,7 +179,11 @@ CMD(pull, "pull", "", CMD_REF(network),
   find_key_if_needed(addr, include_pattern, exclude_pattern, app, false);
 
   if (app.opts.signing_key() == "")
+#if defined(RSE) /* cosmetics-netsync */
+    P(F("doing anonymous pull"));
+#else
     P(F("doing anonymous pull; use -kKEYNAME if you need authentication"));
+#endif
 
   std::list<utf8> uris;
   uris.push_back(addr);
@@ -277,7 +281,11 @@ CMD(clone, "clone", "", CMD_REF(network)
   app.create_workspace(workspace_dir);
 
   if (internal_db)
+#if defined(RSE) /* alt-book-keeping-root */
+    app.set_database(system_path((directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / ws_internal_db_file_name));
+#else
     app.set_database(system_path(bookkeeping_root / ws_internal_db_file_name));
+#endif
   else
     app.set_database(app.opts.dbname);
 
@@ -299,7 +307,11 @@ CMD(clone, "clone", "", CMD_REF(network)
                      app, false);
 
   if (app.opts.signing_key() == "")
+#if defined(RSE) /* cosmetics-netsync */
+    P(F("doing anonymous pull"));
+#else
     P(F("doing anonymous pull; use -kKEYNAME if you need authentication"));
+#endif
 
   if (!app.db.var_exists(default_include_pattern_key)
       || app.opts.set_default)
Index: cmd_ws_commit.cc
--- cmd_ws_commit.cc	e21e2bb8831ce7e62bc428cf32ae10931b5e73e8
+++ cmd_ws_commit.cc	80856a59e293d7aa2bcc14cfce5896e1276a1921
@@ -66,7 +66,14 @@ revision_summary(revision_t const & rev,
 
       for (set<file_path>::const_iterator i = cs.dirs_added.begin();
             i != cs.dirs_added.end(); ++i)
+#if defined(RSE) /* cosmetics-stat */
+        if ((*i) == file_path())
+            out += (F("  added    \"\"")).str() += '\n';
+        else
+            out += (F("  added    %s") % *i).str() += '\n';
+#else
         out += (F("  added    %s") % *i).str() += '\n';
+#endif
 
       for (map<file_path, file_id>::const_iterator i = cs.files_added.begin();
             i != cs.files_added.end(); ++i)
@@ -1396,7 +1403,11 @@ CMD_NO_WORKSPACE(import, "import", "", C
   catch (...)
     {
       // clean up before rethrowing
+#if defined(RSE) /* alt-book-keeping-root */
+      delete_dir_recursive(directory_exists(alt_bookkeeping_root) ? bookkeeping_root : bookkeeping_root);
+#else
       delete_dir_recursive(bookkeeping_root);
+#endif
       throw;
     }
 
Index: diff_patch.cc
--- diff_patch.cc	2d882bd69beabffdef24078ecae588118f8f51cb
+++ diff_patch.cc	d4d89f2eebbe0d2f7f42e6eb014c3960e5dccdb4
@@ -1448,6 +1448,9 @@ make_diff(string const & filename1,
     {
       case unified_diff:
       {
+#if defined(RSE) /* diff-index */
+        ost << "Index: " << filename2 << '\n';
+#endif
         ost << "--- " << filename1 << '\t' << id1 << '\n';
         ost << "+++ " << filename2 << '\t' << id2 << '\n';
 
@@ -1457,6 +1460,9 @@ make_diff(string const & filename1,
       }
       case context_diff:
       {
+#if defined(RSE) /* diff-index */
+        ost << "Index: " << filename2 << '\n';
+#endif
         ost << "*** " << filename1 << '\t' << id1 << '\n';
         ost << "--- " << filename2 << '\t' << id2 << '\n';
 
Index: file_io.cc
--- file_io.cc	358fb964dc42e7f936a136342b93bb3a4744d1b3
+++ file_io.cc	6b452acaa58ca24fa5611ea3e6e82e83a7cf7552
@@ -398,16 +398,36 @@ write_data(file_path const & path, data 
 write_data(file_path const & path, data const & dat)
 {
   // use the bookkeeping root as the temporary directory.
+#if defined(RSE) /* alt-book-keeping-root */
+  if (directory_exists(alt_bookkeeping_root)) {
+      assert_path_is_directory(alt_bookkeeping_root);
+      write_data_impl(path, dat, alt_bookkeeping_root, false);
+  }
+  else {
+#endif
   assert_path_is_directory(bookkeeping_root);
   write_data_impl(path, dat, bookkeeping_root, false);
+#if defined(RSE) /* alt-book-keeping-root */
+  }
+#endif
 }
 
 void
 write_data(bookkeeping_path const & path, data const & dat)
 {
   // use the bookkeeping root as the temporary directory.
+#if defined(RSE) /* alt-book-keeping-root */
+  if (directory_exists(alt_bookkeeping_root)) {
+    assert_path_is_directory(alt_bookkeeping_root);
+    write_data_impl(path, dat, alt_bookkeeping_root, false);
+  }
+  else {
+#endif
   assert_path_is_directory(bookkeeping_root);
   write_data_impl(path, dat, bookkeeping_root, false);
+#if defined(RSE) /* alt-book-keeping-root */
+  }
+#endif
 }
 
 void
Index: lua_hooks.cc
--- lua_hooks.cc	26dbfb8306a7b7b4871f61877c7fd0f72abadfdd
+++ lua_hooks.cc	87a5a20651f2010b1e08c38274b29e0e6434e077
@@ -162,7 +162,11 @@ lua_hooks::workspace_rcfilename(bookkeep
 void
 lua_hooks::workspace_rcfilename(bookkeeping_path & file)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  file = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / "monotonerc";
+#else
   file = bookkeeping_root / "monotonerc";
+#endif
 }
 
 
Index: monotone.cc
--- monotone.cc	8289cbcfbca10f561afa6e06bf279f6b70e93599
+++ monotone.cc	2560f9465773c1178c539e51c66efe1a99109881
@@ -211,12 +211,28 @@ cpp_main(int argc, char ** argv)
               if (!app.opts.dbname.empty())
                 app.db.set_filename(app.opts.dbname);
             }
+#if defined(RSE) /* environment-variables */
+          else
+            {
+              char *cp;
+              if ((cp = getenv("MTN_DBFILE")) != NULL)
+                app.db.set_filename(system_path(cp));
+            }
+#endif
 
           if (app.opts.key_dir_given || app.opts.conf_dir_given)
             {
               if (!app.opts.key_dir.empty())
                 app.keys.set_key_dir(app.opts.key_dir);
             }
+#if defined(RSE) /* environment-variables */
+          else
+            {
+              char *cp;
+              if ((cp = getenv("MTN_KEYDIR")) != NULL)
+                app.keys.set_key_dir(system_path(cp));
+            }
+#endif
 
           // at this point we allow a workspace (meaning search for it
           // and if found read _MTN/options, but don't use the data quite
Index: options_list.hh
--- options_list.hh	1f1eb3ce7a6a72870d0a42ef7f79b58eef621127
+++ options_list.hh	82cddc1ff530f09a32cf7d2c58d6b9ef01449147
@@ -178,6 +178,24 @@ OPTION(diff_options, no_show_encloser, f
   no_show_encloser = true;
 }
 #endif
+#if defined(RSE) /* cosmetics-diff-and-log */
+OPTVAR(diff_options, bool, no_show_header, false)
+OPTION(diff_options, no_show_header, false, "no-show-header",
+     gettext_noop("do not show the summary header"))
+#ifdef option_bodies
+{
+  no_show_header = true;
+}
+#endif
+OPTVAR(diff_options, bool, no_show_separator, false)
+OPTION(diff_options, no_show_separator, false, "no-show-separator",
+     gettext_noop("do not show the separator line"))
+#ifdef option_bodies
+{
+  no_show_separator = true;
+}
+#endif
+#endif
 
 OPT(diffs, "diffs", bool, false, gettext_noop("print diffs along with logs"))
 #ifdef option_bodies
Index: paths.cc
--- paths.cc	d850c3efae62041b8003589817387e5877f63b01
+++ paths.cc	30e8e5ea486bbbda2344474f7bfa86f0b152c438
@@ -226,7 +226,11 @@ in_bookkeeping_dir(string const & path)
 static inline bool
 in_bookkeeping_dir(string const & path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  if (path.size() == 0 || (path[0] != '_' && path[0] != '.'))
+#else
   if (path.size() == 0 || (path[0] != '_'))
+#endif
     return false;
   if (path.size() == 1 || (path[1] != 'M' && path[1] != 'm'))
     return false;
@@ -919,6 +923,9 @@ find_and_go_to_workspace(string const & 
   // first look for the current name of the bookkeeping directory.
   // if we don't find it, look for it under the old name, so that
   // migration has a chance to work.
+#if defined(RSE) /* alt-book-keeping-root */
+  if (!find_bookdir(root, alt_bookkeeping_root_component, current, removed))
+#endif
   if (!find_bookdir(root, bookkeeping_root_component, current, removed))
     if (!find_bookdir(root, old_bookkeeping_root_component, current, removed))
       return false;
Index: paths.hh
--- paths.hh	7dd47155b2962d3e4f5fe8764b11c955791803fc
+++ paths.hh	d29c84938079b1571cc843c7b7c6c61e420421d7
@@ -328,6 +328,15 @@ private:
 // for migration
 #define old_bookkeeping_root_component (path_component("MT"))
 
+#if defined(RSE) /* alt-book-keeping-root */
+#ifndef MTN_ALT_BKROOT
+#define MTN_ALT_BKROOT ".mtn"
+#endif
+#define MTN_ALT_BKROOT_ARG (getenv("MTN_BKROOT") != NULL ? getenv("MTN_BKROOT") : MTN_ALT_BKROOT)
+#define alt_bookkeeping_root           (bookkeeping_path(MTN_ALT_BKROOT_ARG))
+#define alt_bookkeeping_root_component (path_component(MTN_ALT_BKROOT_ARG))
+#endif
+
 // this will always be an absolute path
 class system_path : public any_path
 {
Index: roster_merge.cc
--- roster_merge.cc	d565f9299ca85d77bd1d7f2a29196d7161f0ea08
+++ roster_merge.cc	630d1821e0631e49557bea17008bf88093ec4aa8
@@ -1273,6 +1273,20 @@ roster_merge(roster_t const & left_paren
           result.roster.detach_node(n->self);
           result.invalid_name_conflicts.push_back(conflict);
         }
+#if defined(RSE) /* alt-book-keeping-root */
+      if (result_root->has_child(alt_bookkeeping_root_component))
+        {
+          invalid_name_conflict conflict;
+          node_t n = result_root->get_child(alt_bookkeeping_root_component);
+          conflict.nid = n->self;
+          conflict.parent_name.first = n->parent;
+          conflict.parent_name.second = n->name;
+          I(n->name == alt_bookkeeping_root_component);
+
+          result.roster.detach_node(n->self);
+          result.invalid_name_conflicts.push_back(conflict);
+        }
+#endif
     }
 }
 
Index: std_hooks.lua
--- std_hooks.lua	432725fc36dde06af213797306121385491fda0c
+++ std_hooks.lua	fc4aa2c8e1e8963817dea1a47b21f19ee7292b11
@@ -284,6 +284,15 @@
    if user_log_message == "" or string.sub(user_log_message, -1) ~= "\n" then
       tmp:write("\n")
    end
+   --  #if defined(RSE) /* dot-mtn-message */
+   local template_log_message = read_contents_of_file(".mtn-message", "r")
+   if template_log_message ~= nil then
+      tmp:write(template_log_message)
+      if template_log_message == "" or string.sub(template_log_message, -1) ~= "\n" then
+         tmp:write("\n")
+      end
+   end
+   --  #endif
    tmp:write(basetext)
    io.close(tmp)
 
@@ -1220,4 +1229,165 @@
    function push_netsync_notifier(notifier)
       return push_hook_functions(notifier)
    end
-end
\ No newline at end of file
+end
+
+--  #if defined(RSE) /* extra-command */
+
+--  extra command: "mtn fuse REVISION"
+register_command(
+    "fuse", "REVISION",
+    "Fuse revision into workspace with conflict markers.",
+    "Fuse the specified revision into the current workspace by merging " ..
+    "the revision into the workspace while providing inline conflict " ..
+    "markers for manually resolving the conflicts in the workspace " ..
+    "before comitting the conflicts-resolved workspace as the new " ..
+    "merged revision.",
+    "command_fuse"
+)
+function command_fuse(revision)
+    if revision == nil then
+        io.stderr:write("mtn: fuse: ERROR: revision not given\n")
+        return
+    end
+    if program_exists_in_path("mtn") == 0 then
+        io.stderr:write("mtn: fuse: ERROR: require Monotone command \"mtn\" in PATH\n")
+        return
+    end
+    mtn_automate("get_option", "branch") -- make sure we have a valid workspace
+    local cmd =
+        "MTN_MERGE=diffutils " ..
+        "MTN_MERGE_DIFFUTILS=\"partial,diff3opts=-E\" " ..
+        "mtn " .. "merge_into_workspace " .. revision 
+    local rc = execute("sh", "-c", cmd)
+    if rc ~= 0 then
+        io.stderr:write("mtn: fuse: ERROR: failed to execute command \"" .. cmd .. "\"\n")
+    end
+end
+
+--  extra command: "mtn conflicts"
+register_command(
+    "conflicts", "",
+    "Lists files in workspace containing conflict markers.",
+    "Lists all files in the current workspace containing the " ..
+    "conflict markers produced by GNU diffutils' \"diff3\" " ..
+    "command. This indicates still unresolved merge conflicts.",
+    "command_conflicts"
+)
+function command_conflicts()
+    if program_exists_in_path("egrep") == 0 then
+        io.stderr:write("mtn: conflicts: ERROR: require GNU grep command \"egrep\" in PATH\n")
+        return
+    end
+    mtn_automate("get_option", "branch") -- make sure we have a valid workspace
+    local rc = execute(
+        "egrep",
+        "--files-with-matches",
+        "--recursive",
+        "^(<<<<<<<|=======|>>>>>>>) ",
+        "."
+    )
+end
+
+--  extra command: "mtn rev[ision] REVISION [ANCESTOR-REVISION]"
+register_command(
+    "revision", "REVISION [ANCESTOR-REVISION]",
+    "Shows summary information about revision(s)",
+    "Shows summary information about a particular revision " ..
+    "(or a range of revisions in case an ancestor revision is also specified). " ..
+    "This is just a convenience wrapper command around \"mtn log --diffs\".",
+    "command_revision"
+)
+alias_command(
+    "revision",
+    "rev"
+)
+function command_revision(revision, ancestor)
+    if revision == nil then
+        io.stderr:write("mtn: revision: ERROR: no revision specified\n")
+        return
+    end
+    if ancestor == nil then
+        ancestor = revision
+    end
+    mtn_automate("get_option", "branch") -- make sure we have a valid workspace
+    execute("mtn", "log", "--diffs", "--no-graph", "--from", ancestor, "--to", revision)
+    if rc ~= 0 then
+        io.stderr:write("mtn: revision: ERROR: failed to execute\n")
+    end
+end
+
+--  extra command: "mtn base {upgrade|diff}"
+register_command(
+    "base", "upgrade|diff",
+    "Upgrades or compares current branch against base branch",
+    "Upgrade current branch from base branch or compares current " ..
+    "branch against base branch. The base branch has to be stored " ..
+    "either in the \"mtn:base\" attribute of the root directory " ..
+    "or in a \".mtn-base\" file in the root directory.",
+    "command_base"
+)
+function command_base(op)
+    --  sanity check command line
+    if op == nil then
+        io.stderr:write("mtn: base: ERROR: no operation specified\n")
+        return
+    end
+    if op ~= "upgrade" and op ~= "diff" then
+        io.stderr:write("mtn: base: ERROR: either \"upgrade\" or \"diff\" operation has to be specified\n")
+        return
+    end
+
+    --  determine current branch of workspace
+    local branch_this = nil
+    local rc, txt = mtn_automate("get_option", "branch")
+    if txt ~= nil then
+        branch_this = string.match(txt, "^%s*(%S+)%s*$")
+    end
+    if branch_this == nil then
+        io.stderr:write("mtn: base: ERROR: failed to determine current branch\n")
+        return
+    end
+
+    --  determine base branch of workspace
+    local branch_base = nil
+    local rc, txt = mtn_automate("get_attributes", ".")
+    if txt ~= nil then
+        branch_base = string.match(txt, "attr%s+\"mtn:base\"%s+\"([^\"]+)\"")
+    end
+    if branch_base == nil then
+        local txt = read_contents_of_file(".mtn-base", "r")
+        if txt ~= nil then
+            branch_base = string.match(txt, "^%s*(%S+)%s*$")
+        end
+    end
+    if branch_base == nil then
+        io.stderr:write("mtn: base: ERROR: failed to determine base branch\n")
+        return
+    end
+
+    --  dispatch according to operation
+    if op == "upgrade" then
+        --  upgrade current branch by merging in revisions of base branch
+        local rc = execute("mtn", "propagate", branch_base, branch_this)
+        if rc ~= 0 then
+            io.stderr:write("mtn: revision: ERROR: failed to execute \"mtn propagate\"\n")
+            return
+        end
+        rc = execute("mtn", "update")
+        if rc ~= 0 then
+            io.stderr:write("mtn: revision: ERROR: failed to execute \"mtn update\"\n")
+            return
+        end
+    elseif op == "diff" then
+        --  upgrade current branch by merging in revisions of base branch
+        local rc = execute("mtn", "diff", "-r", "h:" .. branch_base, "-r", "h:" .. branch_this)
+        if rc ~= 0 then
+            io.stderr:write("mtn: revision: ERROR: failed to execute \"mtn diff\"\n")
+            return
+        end
+    end
+    return
+end
+
+--  #endif
+
Index: work.cc
--- work.cc	bcea6fae446e61352e4a12e0259a9094970a9829
+++ work.cc	1282657792888a3159211df49da6afa167e8cbb4
@@ -53,28 +53,44 @@ get_revision_path(bookkeeping_path & m_p
 static void
 get_revision_path(bookkeeping_path & m_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  m_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / revision_file_name;
+#else
   m_path = bookkeeping_root / revision_file_name;
+#endif
   L(FL("revision path is %s") % m_path);
 }
 
 static void
 get_options_path(bookkeeping_path & o_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  o_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / options_file_name;
+#else
   o_path = bookkeeping_root / options_file_name;
+#endif
   L(FL("options path is %s") % o_path);
 }
 
 static void
 get_options_path(system_path const & workspace, system_path & o_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  o_path = (directory_exists(workspace / alt_bookkeeping_root_component) ? (workspace / alt_bookkeeping_root_component) : (workspace / bookkeeping_root_component)) / options_file_name;
+#else
   o_path = workspace / bookkeeping_root_component / options_file_name;
+#endif
   L(FL("options path is %s") % o_path);
 }
 
 static void
 get_inodeprints_path(bookkeeping_path & ip_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  ip_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / inodeprints_file_name;
+#else
   ip_path = bookkeeping_root / inodeprints_file_name;
+#endif
   L(FL("inodeprints path is %s") % ip_path);
 }
 
@@ -205,7 +221,11 @@ workspace::get_user_log_path(bookkeeping
 void
 workspace::get_user_log_path(bookkeeping_path & ul_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  ul_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / user_log_file_name;
+#else
   ul_path = bookkeeping_root / user_log_file_name;
+#endif
   L(FL("user log path is %s") % ul_path);
 }
 
@@ -387,7 +407,11 @@ workspace::get_local_dump_path(bookkeepi
 void
 workspace::get_local_dump_path(bookkeeping_path & d_path)
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  d_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / local_dump_file_name;
+#else
   d_path = bookkeeping_root / local_dump_file_name;
+#endif
   L(FL("local dump path is %s") % d_path);
 }
 
@@ -747,7 +771,11 @@ path_for_detached_nids()
 static inline bookkeeping_path
 path_for_detached_nids()
 {
+#if defined(RSE) /* alt-book-keeping-root */
+  return (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / "detached";
+#else
   return bookkeeping_root / "detached";
+#endif
 }
 
 static inline bookkeeping_path
@@ -1483,9 +1511,15 @@ workspace::perform_pivot_root(file_path 
   N(is_dir_t(new_roster.get_node(new_root)),
     F("proposed new root directory '%s' is not a directory") % new_root);
   {
+#if defined(RSE) /* alt-book-keeping-root */
+    N(!(new_roster.has_node(new_root / bookkeeping_root_component) || new_roster.has_node(new_root / alt_bookkeeping_root_component)),
+      F("proposed new root directory '%s' contains illegal path %s or %s")
+      % new_root % bookkeeping_root % alt_bookkeeping_root);
+#else
     N(!new_roster.has_node(new_root / bookkeeping_root_component),
       F("proposed new root directory '%s' contains illegal path %s")
       % new_root % bookkeeping_root);
+#endif
   }
 
   {
Index: work_migration.cc
--- work_migration.cc	3d58c3332cd195309eacf5cc52d4e88ad66a6c81
+++ work_migration.cc	f044e25cc757899f97d413f3fe109a9bafe73553
@@ -55,9 +55,18 @@ get_ws_format()
 {
   unsigned int format;
   bookkeeping_path f_path = bookkeeping_root / "format";
+#if defined(RSE) /* alt-book-keeping-root */
+  bookkeeping_path alt_f_path = alt_bookkeeping_root / "format";
+  if (!file_exists(f_path) && !file_exists(alt_f_path))
+#else
   if (!file_exists(f_path))
+#endif
     {
+#if defined(RSE) /* alt-book-keeping-root */
+      if (directory_exists(bookkeeping_root) || directory_exists(alt_bookkeeping_root))
+#else
       if (directory_exists(bookkeeping_root))
+#endif
         format = 1;
       else if (directory_exists(file_path() / old_bookkeeping_root_component))
         format = 0;
@@ -69,7 +78,11 @@ get_ws_format()
       data f_dat;
       try
         {
+#if defined(RSE) /* alt-book-keeping-root */
+          read_data(file_exists(alt_f_path) ? alt_f_path : f_path, f_dat);
+#else
           read_data(f_path, f_dat);
+#endif
           format = lexical_cast<unsigned int>(remove_ws(f_dat()));
         }
       catch (exception & e)
@@ -80,7 +93,11 @@ get_ws_format()
       if (format == 1)
         {
           W(F("_MTN/format should not exist in a format 1 workspace; corrected"));
+#if defined(RSE) /* alt-book-keeping-root */
+          delete_file(file_exists(alt_f_path) ? alt_f_path : f_path);
+#else
           delete_file(f_path);
+#endif
         }
     }
   return format;
@@ -90,6 +107,9 @@ workspace::write_ws_format()
 workspace::write_ws_format()
 {
   bookkeeping_path f_path = bookkeeping_root / "format";
+#if defined(RSE) /* alt-book-keeping-root */
+  bookkeeping_path alt_f_path = alt_bookkeeping_root / "format";
+#endif
   // one or other side of this conditional will always be dead code, but
   // both sides should be preserved, to document all historical formats.
   // N.B. this will _not_ do the right thing for format 0.  Which is fine.
@@ -97,10 +117,19 @@ workspace::write_ws_format()
     {
       if (file_exists(f_path))
         delete_file(f_path);
+#if defined(RSE) /* alt-book-keeping-root */
+      if (file_exists(alt_f_path))
+        delete_file(alt_f_path);
+#endif
     }
   else
     {
       data f_dat(lexical_cast<string>(current_workspace_format) + "\n");
+#if defined(RSE) /* alt-book-keeping-root */
+      if (directory_exists(alt_bookkeeping_root))
+        write_data(alt_f_path, f_dat);
+      else
+#endif
       write_data(f_path, f_dat);
     }
 }
@@ -180,7 +209,11 @@ migrate_1_to_2()
   // information, and _MTN/work does not exist; also, there may be more than
   // one parent revision, but we do not have to worry about that here.
 
+#if defined(RSE) /* alt-book-keeping-root */
+  bookkeeping_path rev_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / "revision";
+#else
   bookkeeping_path rev_path = bookkeeping_root / "revision";
+#endif
   data base_rev_data; MM(base_rev_data);
   try 
     {
@@ -196,7 +229,11 @@ migrate_1_to_2()
 
   cset workcs; 
   MM(workcs);
+#if defined(RSE) /* alt-book-keeping-root */
+  bookkeeping_path workcs_path = (directory_exists(alt_bookkeeping_root) ? alt_bookkeeping_root : bookkeeping_root) / "work";
+#else
   bookkeeping_path workcs_path = bookkeeping_root / "work";
+#endif
   bool delete_workcs = false;
   if (file_exists(workcs_path))
     {