Refactored #1750 to support older NGINX versions (fixes #1749)
diff --git a/src/ngx_pagespeed.cc b/src/ngx_pagespeed.cc
index 5f19923..7cf24f8 100644
--- a/src/ngx_pagespeed.cc
+++ b/src/ngx_pagespeed.cc
@@ -6,9 +6,9 @@
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
- *
+ *
* http://www.apache.org/licenses/LICENSE-2.0
- *
+ *
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
@@ -396,6 +396,7 @@
//
// Based on ngx_http_add_cache_control.
ngx_int_t ps_set_cache_control(ngx_http_request_t* r, char* cache_control) {
+#if defined(nginx_version) && nginx_version >= 1023000
ngx_table_elt_t* cc = r->headers_out.cache_control;
if (cc == NULL) {
@@ -422,6 +423,41 @@
cc->value.len = strlen(cache_control);
cc->value.data =
reinterpret_cast<u_char*>(cache_control);
+
+#else
+ // First strip existing cache-control headers.
+ ngx_table_elt_t* header;
+ NgxListIterator it(&(r->headers_out.headers.part));
+ while ((header = it.Next()) != NULL) {
+ if (STR_CASE_EQ_LITERAL(header->key, "Cache-Control")) {
+ // Response headers with hash of 0 are excluded from the response.
+ header->hash = 0;
+ }
+ }
+ // Now add our new cache control header.
+ if (r->headers_out.cache_control.elts == NULL) {
+ ngx_int_t rc = ngx_array_init(&r->headers_out.cache_control, r->pool,
+ 1, sizeof(ngx_table_elt_t*));
+ if (rc != NGX_OK) {
+ return NGX_ERROR;
+ }
+ }
+ ngx_table_elt_t** cache_control_headers = static_cast<ngx_table_elt_t**>(
+ ngx_array_push(&r->headers_out.cache_control));
+ if (cache_control_headers == NULL) {
+ return NGX_ERROR;
+ }
+ cache_control_headers[0] = static_cast<ngx_table_elt_t*>(
+ ngx_list_push(&r->headers_out.headers));
+ if (cache_control_headers[0] == NULL) {
+ return NGX_ERROR;
+ }
+ cache_control_headers[0]->hash = 1;
+ ngx_str_set(&cache_control_headers[0]->key, "Cache-Control");
+ cache_control_headers[0]->value.len = strlen(cache_control);
+ cache_control_headers[0]->value.data =
+ reinterpret_cast<u_char*>(cache_control);
+#endif
return NGX_OK;
}
@@ -431,6 +467,7 @@
// Use headers_out.cache_control instead of looking for Cache-Control in
// headers_out.headers, because if an upstream sent multiple Cache-Control
// headers they're already combined in headers_out.cache_control.
+#if defined(nginx_version) && nginx_version >= 1023000
ngx_table_elt_t* cc = r->headers_out.cache_control;
bool first_segment = true;
@@ -442,10 +479,29 @@
cache_control->append(", ");
}
cache_control->append(reinterpret_cast<char*>(cc->value.data),
- cc->value.len);
+ cc->value.len);
}
cc = cc->next;
}
+#else
+ auto ccp = static_cast<ngx_table_elt_t**>(r->headers_out.cache_control.elts);
+ if (ccp == nullptr) {
+ return false; // Header not present.
+ }
+ bool first_segment = true;
+ for (ngx_uint_t i = 0; i < r->headers_out.cache_control.nelts; i++) {
+ if (ccp[i]->hash == 0) {
+ continue; // Elements with a hash of 0 are marked as excluded.
+ }
+ if (first_segment) {
+ first_segment = false;
+ } else {
+ cache_control->append(", ");
+ }
+ cache_control->append(reinterpret_cast<char*>(ccp[i]->value.data),
+ ccp[i]->value.len);
+ }
+#endif
return true;
}
