@echo off
::  PRE-REVPROP-CHANGE HOOK
:: 
::  The pre-revprop-change hook is invoked before a revision property
::  is added, modified or deleted.  Subversion runs this hook by invoking
::  a program (script, executable, binary, etc.) named 'pre-revprop-change'
::  (for which this file is a template), with the following ordered
::  arguments:
:: 
::    [1] REPOS-PATH   (the path to this repository)
::    [2] REV          (the revision being tweaked)
::    [3] USER         (the username of the person tweaking the property)
::    [4] PROPNAME     (the property being set on the revision)
::    [5] ACTION       (the property is being 'A'dded, 'M'odified, or 'D'eleted)
:: 
::    [STDIN] PROPVAL  ** the new property value is passed via STDIN.
:: 
::  If the hook program exits with success, the propchange happens; but
::  if it exits with failure (non-zero), the propchange doesn't happen.
::  The hook program can use the 'svnlook' utility to examine the 
::  existing value of the revision property.
:: 
::  WARNING: unlike other hooks, this hook MUST exist for revision
::  properties to be changed.  If the hook does not exist, Subversion 
::  will behave as if the hook were present, but failed.  The reason
::  for this is that revision properties are UNVERSIONED, meaning that
::  a successful propchange is destructive;  the old value is gone
::  forever.  We recommend the hook back up the old value somewhere.
:: 
::  On a Unix system, the normal procedure is to have 'pre-revprop-change'
::  invoke other programs to do the real work, though it may do the
::  work itself too.
:: 
::  Note that 'pre-revprop-change' must be executable by the user(s) who will
::  invoke it (typically the user httpd runs as), and that user must
::  have filesystem-level permission to access the repository.
:: 
::  On a Windows system, you should name the hook program
::  'pre-revprop-change.bat' or 'pre-revprop-change.exe',
::  but the basic idea is the same.
:: 
::  The hook program typically does not inherit the environment of
::  its parent process.  For example, a common problem is for the
::  PATH environment variable to not be set to its usual value, so
::  that subprograms fail to launch unless invoked via absolute path.
::  If you're having unexpected problems with a hook program, the
::  culprit may be unusual (or missing) environment variables.
::  
::  Here is an example hook script, for a Unix /bin/sh interpreter.
::  For more examples and pre-written hooks, see those in
::  the Subversion repository at
::  http://svn.apache.org/repos/asf/subversion/trunk/tools/hook-scripts/ and
::  http://svn.apache.org/repos/asf/subversion/trunk/contrib/hook-scripts/

@ECHO OFF
setlocal
set repos=%1
set rev=%2
set user=%3
set propname=%4
set action=%5

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:: Only allow changes to svn:log. The author, date and other revision
:: properties cannot be changed
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
if /I '%propname%'=='svn:svn-lock' goto VALID_PROPNAME
if /I '%propname%'=='svn:sync-lock' goto VALID_PROPNAME
if /I '%propname%'=='svn:sync-from-url' goto VALID_PROPNAME
if /I '%propname%'=='svn:sync-from-uuid' goto VALID_PROPNAME
if /I '%propname%'=='svn:sync-last-merged-rev' goto VALID_PROPNAME
if /I '%propname%'=='svn:sync-currently-copying' goto VALID_PROPNAME
if /I '%propname%'=='svn:date' goto VALID_PROPNAME
if /I '%propname%'=='svn:author' goto VALID_PROPNAME
if /I '%propname%'=='svn:log' goto VALID_PROPNAME
goto ERROR_PROPNAME

:VALID_PROPNAME
echo Propname=%propname% is allowed >&2

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:: Only allow modifications to svn:log (no addition/overwrite or deletion)
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
rem echo Check [action=%action%] >&2
if /I '%action%'=='A' goto VALID_ACTION
if /I '%action%'=='D' goto VALID_ACTION
if /I '%action%'=='M' goto VALID_ACTION
goto ERROR_ACTION

:VALID_ACTION
echo Action=%action% is allowed >&2
 
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
:: Make sure that the new svn:log message contains some text.
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
::set bIsEmpty=true
::for /f "tokens=*" %%g in ('find /V ""') do (
 ::set bIsEmpty=false
::)
::if '%bIsEmpty%'=='true' goto ERROR_LOG_EMPTY
::
:::VALID_LOG
::echo Log accepted >&2
 
goto :eof
 
:ERROR_LOG_EMPTY
echo Empty svn:log properties are not allowed. >&2
goto ERROR_EXIT
 
:ERROR_PROPNAME
echo Only changes to svn:log revision properties are allowed [prop=%propname%]. >&2
goto ERROR_EXIT
 
:ERROR_ACTION
echo Only modifications to svn:log revision properties are allowed [action=%action%]. >&2
goto ERROR_EXIT
 
:ERROR_EXIT
exit /b 1
