Add a note about coccinelle use.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1725398 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/docs/log-message-tags/README b/docs/log-message-tags/README
index d177686124b3f9176ac1c6b162f985249f5b0a07..6761733303e3e395dc7a20eb4fdd19e01fbefbcb 100644 (file)
--- a/docs/log-message-tags/README
+++ b/docs/log-message-tags/README
@@ -51,3 +51,16 @@ spatch -sp_file $DIR/find-messages.cocci -in_place -macro_file $DIR/macros.h <fi
 After the initial addition of tags, calling spatch on the same file again may
 be a bad idea. But it may still be useful when adding larger pieces of code to
 httpd.
+
+Depending on the build details of coccinelle, the regular expressions in the
+spatch files can either be in normal PCRE form, or in OCAML Str regexp form.
+If your build only supports the latter, you will have to put a backslash in
+front of every '(', ')' and '|' that is part of a regexp in the cocci file.
+
+Example:
+- original lines
+identifier level =~ "^APLOG_(EMERG|ALERT|CRIT|ERR|WARNING|NOTICE|INFO|STARTUP|DEBUG)$";
+identifier fn =~ "^ap_log_(|r|c|p)error$";
+- new lines
+identifier level =~ "^APLOG_\(EMERG\|ALERT\|CRIT\|ERR\|WARNING\|NOTICE\|INFO\|STARTUP\|DEBUG\)$";
+identifier fn =~ "^ap_log_\(\|r\|c\|p\)error$";