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/item_node.h"
  10 #include "tools/gn/item_tree.h"
  11 #include "tools/gn/scheduler.h"
  12
  13 Config::Config(const Settings* settings, const Label& label)
  14     : Item(settings, label) {
  15 }
  16
  17 Config::~Config() {
  18 }
  19
  20 Config* Config::AsConfig() {
  21   return this;
  22 }
  23
  24 const Config* Config::AsConfig() const {
  25   return this;
  26 }
  27
  28 // static
  29 Config* Config::GetConfig(const Settings* settings,
  30                           const LocationRange& specified_from_here,
  31                           const Label& label,
  32                           Item* dep_from,
  33                           Err* err) {
  34   DCHECK(!label.is_null());
  35
  36   ItemTree* tree = &settings->build_settings()->item_tree();
  37   base::AutoLock lock(tree->lock());
  38
  39   ItemNode* node = tree->GetExistingNodeLocked(label);
  40   Config* config = NULL;
  41   if (!node) {
  42     config = new Config(settings, label);
  43     node = new ItemNode(config);
  44     node->set_originally_referenced_from_here(specified_from_here);
  45     tree->AddNodeLocked(node);
  46
  47     // Only schedule loading the given target if somebody is depending on it
  48     // (and we optimize by not re-asking it to run the current file).
  49     // Otherwise, we're probably generating it right now.
  50     if (dep_from && dep_from->label().dir() != label.dir()) {
  51       settings->build_settings()->toolchain_manager().ScheduleInvocationLocked(
  52           specified_from_here, label.GetToolchainLabel(), label.dir(),
  53           err);
  54     }
  55   } else if ((config = node->item()->AsConfig())) {
  56     // Previously saw this item as a config.
  57
  58     // If we have no dep_from, we're generating it. In this case, it had better
  59     // not already be generated.
  60     if (!dep_from && node->state() != ItemNode::REFERENCED) {
  61       *err = Err(specified_from_here, "Duplicate config definition.",
  62           "You already told me about a config with this name.");
  63       return NULL;
  64     }
  65   } else {
  66     // Previously saw this thing as a non-config.
  67     *err = Err(specified_from_here,
  68                "Config name already used.",
  69                "Previously you specified a " +
  70                node->item()->GetItemTypeName() + " with this name instead.");
  71     return NULL;
  72   }
  73
  74   // Keep a record of the guy asking us for this dependency. We know if
  75   // somebody is adding a dependency, that guy it himself not resolved.
  76   if (dep_from) {
  77     if (!dep_from->item_node()->AddDependency(
  78             settings->build_settings(), specified_from_here, node, err))
  79       return NULL;
  80   }
  81   return config;
  82 }