Check also err_headers_out for an already set Content-Encoding:

gzip header. This prevents gzip compressed content from a CGI
script from being compressed once more.

PR: 17797


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@98948 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 17 insertions, 0 deletions

diff --git a/CHANGES b/CHANGES
index 02019f88d6..cfb38456e6 100644
--- a/CHANGES
+++ b/CHANGES
@@ -2,6 +2,11 @@ Changes with Apache 2.1.0-dev
 
   [Remove entries to the current 2.0 section below, when backported]
 
+  *) mod_deflate: Check also err_headers_out for an already set
+     Content-Encoding: gzip header. This prevents gzip compressed content
+     from a CGI script from being compressed once more. PR 17797.
+     [André Malo]
+
   *) Forward port: Escape special characters (especially control
      characters) in mod_log_config to make a clear distinction between
      client-supplied strings (with special characters) and server-side
diff --git a/modules/filters/mod_deflate.c b/modules/filters/mod_deflate.c
index c14b10fff8..db65bd2f24 100644
--- a/modules/filters/mod_deflate.c
+++ b/modules/filters/mod_deflate.c
@@ -329,6 +329,18 @@ static apr_status_t deflate_out_filter(ap_filter_t *f,
          */
         encoding = apr_table_get(r->headers_out, "Content-Encoding");
         if (encoding) {
+            const char *err_enc;
+
+            err_enc = apr_table_get(r->err_headers_out, "Content-Encoding");
+            if (err_enc) {
+                encoding = apr_pstrcat(r->pool, encoding, ",", err_enc, NULL);
+            }
+        }
+        else {
+            encoding = apr_table_get(r->err_headers_out, "Content-Encoding");
+        }
+
+        if (encoding) {
             const char *tmp = encoding;
 
             token = ap_get_token(r->pool, &tmp, 0);