--- a/src/core/ngx_file.c
+++ b/src/core/ngx_file.c
@@ -9,11 +9,102 @@
 #include <ngx_core.h>
 
 
+static ngx_int_t ngx_test_full_name(ngx_str_t *name);
+
+
 static ngx_atomic_t   temp_number = 0;
 ngx_atomic_t         *ngx_temp_number = &temp_number;
 ngx_atomic_int_t      ngx_random_number = 123456;
 
 
+ngx_int_t
+ngx_get_full_name(ngx_pool_t *pool, ngx_str_t *prefix, ngx_str_t *name)
+{
+    size_t      len;
+    u_char     *p, *n;
+    ngx_int_t   rc;
+
+    rc = ngx_test_full_name(name);
+
+    if (rc == NGX_OK) {
+        return rc;
+    }
+
+    len = prefix->len;
+
+#if (NGX_WIN32)
+
+    if (rc == 2) {
+        len = rc;
+    }
+
+#endif
+
+    n = ngx_pnalloc(pool, len + name->len + 1);
+    if (n == NULL) {
+        return NGX_ERROR;
+    }
+
+    p = ngx_cpymem(n, prefix->data, len);
+    ngx_cpystrn(p, name->data, name->len + 1);
+
+    name->len += len;
+    name->data = n;
+
+    return NGX_OK;
+}
+
+
+static ngx_int_t
+ngx_test_full_name(ngx_str_t *name)
+{
+#if (NGX_WIN32)
+    u_char  c0, c1;
+
+    c0 = name->data[0];
+
+    if (name->len < 2) {
+        if (c0 == '/') {
+            return 2;
+        }
+
+        return NGX_DECLINED;
+    }
+
+    c1 = name->data[1];
+
+    if (c1 == ':') {
+        c0 |= 0x20;
+
+        if ((c0 >= 'a' && c0 <= 'z')) {
+            return NGX_OK;
+        }
+
+        return NGX_DECLINED;
+    }
+
+    if (c1 == '/') {
+        return NGX_OK;
+    }
+
+    if (c0 == '/') {
+        return 2;
+    }
+
+    return NGX_DECLINED;
+
+#else
+
+    if (name->data[0] == '/') {
+        return NGX_OK;
+    }
+
+    return NGX_DECLINED;
+
+#endif
+}
+
+
 ssize_t
 ngx_write_chain_to_temp_file(ngx_temp_file_t *tf, ngx_chain_t *chain)
 {