mod_headers_with_notes.patch

--- httpd-2.2.17.orig/modules/metadata/mod_headers.c	2010-08-25 23:12:46.000000000 +0900
+++ httpd-2.2.17/modules/metadata/mod_headers.c	2011-01-28 12:20:10.000000000 +0900
@@ -126,6 +126,7 @@
     ap_regex_t *regex;
     const char *condition_var;
     const char *subs;
+    int use_notes;
 } header_entry;
 
 /* echo_do is used for Header echo to iterate through the request headers*/
@@ -215,6 +216,16 @@
     }
 }
 
+static const char *header_request_notes_var(request_rec *r, char *a)
+{
+    const char *s = apr_table_get(r->notes,a);
+
+    if (s)
+        return unwrap_header(r->pool, s);
+    else
+        return "(null)";
+}
+
 /*
  * Config routines
  */
@@ -477,15 +488,32 @@
             condition_var = condition_early;
         }
         else {
-            if (strncasecmp(envclause, "env=", 4) != 0) {
-                return "error: envclause should be in the form env=envar";
+            if ( envclause[0] == 'e' ) {
+                if (strncasecmp(envclause, "env=", 4) != 0) {
+                    return "error: envclause should be in the form env=envar";
+                }
+                if ((envclause[4] == '\0')
+                    || ((envclause[4] == '!') && (envclause[5] == '\0'))) {
+                    return "error: missing environment variable name. "
+                        "envclause should be in the form env=envar ";
+                }
+                condition_var = envclause + 4;
             }
-            if ((envclause[4] == '\0')
-                || ((envclause[4] == '!') && (envclause[5] == '\0'))) {
-                return "error: missing environment variable name. "
-                    "envclause should be in the form env=envar ";
+            else if ( envclause[0] == 'n' ) {
+                if (strncasecmp(envclause, "notes=", 6) != 0) {
+                    return "error: envclause should be in the form notes=notesvar";
+                }
+                if ((envclause[6] == '\0')
+                    || ((envclause[6] == '!') && (envclause[7] == '\0'))) {
+                    return "error: missing notes variable name. "
+                        "envclause should be in the form notes=envar ";
+                }
+                condition_var = envclause + 6;
+                new->use_notes = 1;
+            }
+            else {
+                return "error: envclause should be in the form env=env_var or notes=notesvar";
             }
-            condition_var = envclause + 4;
         }
     }
 
@@ -619,6 +647,7 @@
     echo_do v;
     int i;
     const char *val;
+    apr_table_t *t;
 
     for (i = 0; i < fixup->nelts; ++i) {
         header_entry *hdr = &((header_entry *) (fixup->elts))[i];
@@ -634,12 +663,18 @@
         }
         /* Have any conditional envar-controlled Header processing to do? */
         else if (envar && !early) {
+            if ( hdr->use_notes ) {
+                t = r->notes;
+            }
+            else {
+                t = r->subprocess_env;
+            }
             if (*envar != '!') {
-                if (apr_table_get(r->subprocess_env, envar) == NULL)
+                if (apr_table_get(t, envar) == NULL)
                     continue;
             }
             else {
-                if (apr_table_get(r->subprocess_env, &envar[1]) != NULL)
+                if (apr_table_get(t, &envar[1]) != NULL)
                     continue;
             }
         }
@@ -854,6 +889,7 @@
     register_format_tag_handler("t", (const void *)header_request_time);
     register_format_tag_handler("e", (const void *)header_request_env_var);
     register_format_tag_handler("s", (const void *)header_request_ssl_var);
+    register_format_tag_handler("n", (const void *)header_request_notes_var);
 
     return OK;
 }