tools/gn/config.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "tools/gn/config.h"
   6
   7 #include "tools/gn/err.h"
   8 #include "tools/gn/input_file_manager.h"
   9 #include "tools/gn/scheduler.h"
  10
  11 Config::Config(const Settings* settings, const Label& label)
  12     : Item(settings, label),
  13       resolved_(false) {
  14 }
  15
  16 Config::~Config() {
  17 }
  18
  19 Config* Config::AsConfig() {
  20   return this;
  21 }
  22
  23 const Config* Config::AsConfig() const {
  24   return this;
  25 }
  26
  27 bool Config::OnResolved(Err* err) {
  28   DCHECK(!resolved_);
  29   resolved_ = true;
  30
  31   if (!configs_.empty()) {
  32     // Subconfigs, flatten.
  33     //
  34     // Implementation note for the future: Flattening these here means we
  35     // lose the ability to de-dupe subconfigs. If a subconfig is listed as
  36     // a separate config or a subconfig that also applies to the target, the
  37     // subconfig's flags will be duplicated.
  38     //
  39     // If we want to be able to de-dupe these, here's one idea. As a config is
  40     // resolved, inline any sub-sub configs so the configs_ vector is a flat
  41     // list, much the same way that libs and lib_dirs are pushed through
  42     // targets. Do the same for Target.configs_ when a target is resolved. This
  43     // will naturally de-dupe and also prevents recursive config walking to
  44     // compute every possible flag, although it will expand the configs list on
  45     // a target nontrivially (depending on build configuration).
  46     composite_values_ = own_values_;
  47     for (const auto& pair : configs_)
  48       composite_values_.AppendValues(pair.ptr->resolved_values());
  49   }
  50   return true;
  51 }