* Patch from Thomas Schwinge to switch from --svn to --rcs=svn, etc,

  to pave the way for adding other RCS support. This also changes the
  setup files, where before they had svn => 1 or svn => 0, now they have
  rcs => "svn" or rcs => "".
* Add a debian/NEWS file with upgrade notes.
* Load whatever rcs module is specified, so new ones can be just dropped in
  as plugins and work.
* Add some basic docs about writing RCS modules.

4 files changed, 27 insertions, 15 deletions

diff --git a/doc/ikiwiki.setup b/doc/ikiwiki.setup
index 87a19aefc..d6ca7bb0b 100644
--- a/doc/ikiwiki.setup
+++ b/doc/ikiwiki.setup
@@ -20,8 +20,8 @@ use IkiWiki::Setup::Standard {
 	#diffurl => "http://svn.someurl/trunk/[[file]]?root=wiki&r1=[[r1]]&r2=[[r2]]",
 	#templatedir => "/usr/share/ikiwiki/templates",
 	
-	# Whether to integrate with svn.
-	svn => 1,
+	#rcs => "", # don't use svn
+	rcs => "svn", # use svn (the default)
 	svnrepo => "/svn/wiki",
 	svnpath => "trunk",
 
diff --git a/doc/plugins.mdwn b/doc/plugins.mdwn
index 6f4127e78..7773e71a9 100644
--- a/doc/plugins.mdwn
+++ b/doc/plugins.mdwn
@@ -1,13 +1,14 @@
-Plugins can be used to add additional features to ikiwiki. It's possible to
-[[write]] your own plugins, or you can install and use plugins contributed by
-others. 
+Plugins can be used to add additional features to ikiwiki. Ikiwiki's
+backend RCS support is also pluggable, so support for new revision control
+systems can be added to ikiwiki. It's possible to [[write]] your own plugins,
+or you can install and use plugins contributed by others. 
 
 The ikiiki package includes some standard plugins that are installed and
 by default. These include [[inline]], [[pagecount]], and [[brokenlinks]].
 Of these, [[inline]] is enabled by default.
 
-To enable other plugins, use the `--plugin` switch described in [[usage]], or the equivilant line in
-[[ikiwiki.setup]].
+To enable other plugins, use the `--plugin` switch described in [[usage]],
+or the equivalent line in [[ikiwiki.setup]].
 
 ## Plugin directory
 
@@ -23,4 +24,4 @@ for a list of the directories in that path. All plugins are in the
 IkiWiki::Plugin namespace, so they go in a IkiWiki/Plugin subdirectory
 inside the perl search path. For example, if your perl looks in
 `/usr/local/lib/site_perl` for modules, you can locally install ikiwiki
-plugins to `/usr/local/lib/site_perl/IkiWiki/Plugin`
\ No newline at end of file
+plugins to `/usr/local/lib/site_perl/IkiWiki/Plugin`
diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index c4f668373..7bbde94fa 100644
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -71,3 +71,13 @@ use the following hashes, using a page name as the key:
   Many plugins will need to add dependencies to this hash; the best way to do
   it is by using the IkiWiki::add_depends function, which takes as its
   parameters the page name and a [[GlobList]] of dependencies to add.
+
+## RCS plugins
+
+ikiwiki's support for revision control systems also uses pluggable perl
+modules. These are in the `IkiWiki::RCS` namespace, for example
+`IkiWiki::RCS::svn`. 
+
+Each RCS plugin must support all the IkiWiki::rcs_* functions.
+See IkiWiki::RCS::Stub for the full list of functions. It's ok if
+rcs_getctime does nothing except for throwing an error.
diff --git a/doc/usage.mdwn b/doc/usage.mdwn
index c4d1f5818..c30d799fd 100644
--- a/doc/usage.mdwn
+++ b/doc/usage.mdwn
@@ -90,17 +90,18 @@ These options configure the wiki.
   Enable email notification of commits. This should be used when running
   ikiwiki as a [[Subversion]] [[post-commit]] hook.
 
-* --svn, --nosvn
+* --rcs=svn, --no-rcs
 
-  Enable or disable use of [[subversion]]. If subversion is enabled, the
-  `source` directory is assumed to be a working copy, and is automatically
-  updated before building the wiki. 
+  Enable or disable use of a revision control system.
 
-  In [[CGI]] mode, with subversion enabled pages edited via the web will be
-  committed to subversion. Also, the [[RecentChanges]] link will be placed
+  If you use svn ([[Subversion]]), the `source` directory is assumed to be
+  a working copy, and is automatically updated before building the wiki.
+
+  In [[CGI]] mode, with a revision control system enabled pages edited via
+  the web will be committed. Also, the [[RecentChanges]] link will be placed
   on pages.
 
-  Subversion is enabled by default.
+  svn is enabled by default.
 
 * --svnrepo /svn/wiki