blob: 774f866334a76a3d3850ed63218db37a8257f357 [file] [log] [blame]
// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "tools/gn/import_manager.h"
#include "base/memory/scoped_ptr.h"
#include "base/stl_util.h"
#include "tools/gn/parse_tree.h"
#include "tools/gn/scheduler.h"
namespace {
// Returns a newly-allocated scope on success, null on failure.
Scope* UncachedImport(const Settings* settings,
const SourceFile& file,
const ParseNode* node_for_err,
Err* err) {
const ParseNode* node = g_scheduler->input_file_manager()->SyncLoadFile(
node_for_err->GetRange(), settings->build_settings(), file, err);
if (!node)
return NULL;
const BlockNode* block = node->AsBlock();
CHECK(block);
scoped_ptr<Scope> scope(new Scope(settings->base_config()));
scope->SetProcessingImport();
block->ExecuteBlockInScope(scope.get(), err);
if (err->has_error())
return NULL;
scope->ClearProcessingImport();
return scope.release();
}
} // namesapce
ImportManager::ImportManager() {
}
ImportManager::~ImportManager() {
STLDeleteContainerPairSecondPointers(imports_.begin(), imports_.end());
}
bool ImportManager::DoImport(const SourceFile& file,
const ParseNode* node_for_err,
Scope* scope,
Err* err) {
// See if we have a cached import, but be careful to actually do the scope
// copying outside of the lock.
const Scope* imported_scope = NULL;
{
base::AutoLock lock(lock_);
ImportMap::const_iterator found = imports_.find(file);
if (found != imports_.end())
imported_scope = found->second;
}
if (!imported_scope) {
// Do a new import of the file.
imported_scope = UncachedImport(scope->settings(), file,
node_for_err, err);
if (!imported_scope)
return false;
// We loaded the file outside the lock. This means that there could be a
// race and the file was already loaded on a background thread. Recover
// from this and use the existing one if that happens.
{
base::AutoLock lock(lock_);
ImportMap::const_iterator found = imports_.find(file);
if (found != imports_.end()) {
delete imported_scope;
imported_scope = found->second;
} else {
imports_[file] = imported_scope;
}
}
}
return imported_scope->NonRecursiveMergeTo(scope, node_for_err,
"import", err);
}