urlto(): if $from is undef, return a local path, not an absolute URL

[ikiwiki.git] / doc / plugins / write.mdwn

diff --git a/doc/plugins/write.mdwn b/doc/plugins/write.mdwn
index d5bd1dd7648bf867b3dfe1f3a21f71038e40ee83..33db3e707d8ad816bcc80a807ec8c8098fe72ec7 100644 (file)
--- a/doc/plugins/write.mdwn
+++ b/doc/plugins/write.mdwn
@@ -988,6 +988,10 @@ Construct a relative url to the first parameter from the page named by the
 second. The first parameter can be either a page name, or some other
 destination file, as registered by `will_render`.
 
+If the second parameter is `undef`, the URL will be valid from any page on the
+wiki, or from the CGI; if possible it'll be a path starting with `/`, but an
+absolute URL will be used if the wiki and the CGI are on different servers.
+
 If the third parameter is passed and is true, an absolute url will be
 constructed instead of the default relative url.
 
@@ -1154,8 +1158,6 @@ context, and the whole diff in scalar context.
 This is used to get the page creation time for a file from the RCS, by looking
 it up in the history.
 
-It's ok if this is not implemented, and throws an error.
-
 If the RCS cannot determine a ctime for the file, return 0.
 
 #### `rcs_getmtime($)`
@@ -1176,9 +1178,9 @@ sense to implement for all RCSs.
 
 It should examine the incoming changes, and do any sanity 
 checks that are appropriate for the RCS to limit changes to safe file adds,
-removes, and changes. If something bad is found, it should exit
-nonzero, to abort the push. Otherwise, it should return a list of
-files that were changed, in the form:
+removes, and changes. If something bad is found, it should die, to abort
+the push. Otherwise, it should return a list of files that were changed,
+in the form:
 
        {
                file => # name of file that was changed
@@ -1191,6 +1193,28 @@ files that were changed, in the form:
 The list will then be checked to make sure that each change is one that
 is allowed to be made via the web interface.
 
+#### `rcs_preprevert($)`
+
+This is called by the revert web interface. It is passed a RCS-specific
+change ID, and should determine what the effects would be of reverting
+that change, and return the same data structure as `rcs_receive`.
+
+Like `rcs_receive`, it should do whatever sanity checks are appropriate
+for the RCS to limit changes to safe changes, and die if a change would
+be unsafe to revert.
+
+#### `rcs_revert($)`
+
+This is called by the revert web interface. It is passed a named
+parameter rev that is the RCS-specific change ID to revert.
+
+It should try to revert the specified rev, and leave the reversion staged
+so `rcs_commit_staged` will complete it. It should return undef on _success_
+and an error message on failure.
+
+This hook and `rcs_preprevert` are optional, if not implemented, no revert
+web interface will be available.
+
 ### PageSpec plugins
 
 It's also possible to write plugins that add new functions to