--- svn2cl.sh	2010-10-23 13:59:12.000000000 +0200
+++ svn2cl.sh.oden	2011-09-20 13:30:32.234804656 +0200
@@ -49,6 +49,7 @@ REPARAGRAPH="no"
 SEPARATEDAYLOGS="no"
 ACTIONS="no"
 CHANGELOG=""
+CHANGELOG_BAK=""
 OUTSTYLE="cl"
 SVNLOGCMD="svn --verbose --xml log"
 SVNINFOCMD="svn --non-interactive info"
@@ -58,6 +59,7 @@ TITLE="ChangeLog"
 REVISION_LINK="#r"
 TICKET_LINK=""
 TMPFILES=""
+ACCUM="no"
 AWK="awk"
 
 # do command line checking
@@ -166,6 +168,10 @@ do
       OUTSTYLE="html"
       shift
       ;;
+    --accum)
+      ACCUM="yes"
+      shift
+      ;;
     -r|--revision|-c|--change|--targets|-l|--limit)
       # add these as extra options to the log command (with argument)
       arg=`echo "$2" | sed "s/'/'\"'\"'/g"`
@@ -236,6 +242,7 @@ do
       echo "  --stdout             output to stdout instead of ChangeLog"
       echo "  --authors=FILE       file to read for authors"
       echo "  --html               output as html instead of plain text"
+      echo "  --accum              add to an existing file"
       echo "  -h, --help           display this help and exit"
       echo "  -V, --version        output version information and exit"
       echo ""
@@ -313,6 +320,19 @@ fi
 # redirect stdout to the changelog file if needed
 if [ "x$CHANGELOG" != "x-" ]
 then
+  if [ "$ACCUM" = "yes" ]
+  then
+    date=`sed -ne 's/^\([0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]\s\+\(\w\+\s\+\)\?[0-9][0-9]:[0-9][0-9]\).*/\1/;T;p;q' $CHANGELOG 2>/dev/null`
+    if [ -n "$date" ]
+    then
+      SVNLOGCMD="$SVNLOGCMD -r 'HEAD:{$date}'"
+    else
+        echo "no date found in existing changelog file, accum skipped"
+        ACCUM="no"
+    fi
+    CHANGELOG_BAK="$CHANGELOG.bak"
+    cp -f "$CHANGELOG" "$CHANGELOG_BAK"
+  fi
   exec > "$CHANGELOG"
 fi
 
@@ -336,6 +356,8 @@ eval "$SVNLOGCMD" | \
            --nonet \
            "$XSL" -
 
+[ -n "$CHANGELOG_BAK" ] && cat "$CHANGELOG_BAK"
+
 # clean up temporary files
 [ -n "$TMPFILES" ] && eval "rm -f $TMPFILES"