Nginx patch to make WebDAV module respect if-unmodified-since

gistfile1.txt

Index: src/http/modules/ngx_http_dav_module.c
===================================================================
--- src/http/modules/ngx_http_dav_module.c	(revision 4898)
+++ src/http/modules/ngx_http_dav_module.c	(working copy)
@@ -55,6 +55,9 @@
 static ngx_int_t ngx_http_dav_copy_tree_file(ngx_tree_ctx_t *ctx,
     ngx_str_t *path);
 
+static ngx_int_t ngx_http_dav_check_unmodified(ngx_http_request_t *r,
+                                               ngx_file_info_t *fi);
+
 static ngx_int_t ngx_http_dav_depth(ngx_http_request_t *r, ngx_int_t dflt);
 static ngx_int_t ngx_http_dav_error(ngx_log_t *log, ngx_err_t err,
     ngx_int_t not_found, char *failed, u_char *path);
@@ -237,6 +240,7 @@
             ngx_http_finalize_request(r, NGX_HTTP_CONFLICT);
             return;
         }
+        if (ngx_http_dav_check_unmodified(r, &fi)) return;
     }
 
     dlcf = ngx_http_get_module_loc_conf(r, ngx_http_dav_module);
@@ -353,6 +357,8 @@
 
     } else {
 
+        if (ngx_http_dav_check_unmodified(r, &fi)) return NGX_DONE;
+
         /*
          * we do not need to test (r->uri.data[r->uri.len - 1] == '/')
          * because ngx_link_info("/file/") returned NGX_ENOTDIR above
@@ -707,6 +713,8 @@
 
         /* destination exists */
 
+        if (ngx_http_dav_check_unmodified(r, &fi)) return NGX_DONE;
+
         if (ngx_is_dir(&fi) && !slash) {
             ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
                           "\"%V\" could not be %Ved to collection \"%V\"",
@@ -967,6 +975,22 @@
     return NGX_OK;
 }
 
+static ngx_int_t
+ngx_http_dav_check_unmodified(ngx_http_request_t *r, ngx_file_info_t *fi)
+{
+    time_t date;
+    if (r->headers_in.if_unmodified_since) {
+        date =
+            ngx_http_parse_time(r->headers_in.if_unmodified_since->value.data,
+                                r->headers_in.if_unmodified_since->value.len);
+        if (date < ngx_file_mtime(fi)) {
+            ngx_http_filter_finalize_request(r, NULL,
+                                             NGX_HTTP_PRECONDITION_FAILED);
+            return 1;
+        }
+    }
+    return 0;
+}
 
 static ngx_int_t
 ngx_http_dav_depth(ngx_http_request_t *r, ngx_int_t dflt)