tools/gn/builder_record.h

   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 #ifndef TOOLS_GN_BUILDER_RECORD_H_
   6 #define TOOLS_GN_BUILDER_RECORD_H_
   7
   8 #include <set>
   9
  10 #include "base/macros.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "tools/gn/item.h"
  13 #include "tools/gn/location.h"
  14
  15 class ParseNode;
  16
  17 // This class is used by the builder to manage the loading of the dependency
  18 // tree. It holds a reference to an item and links to other records that the
  19 // item depends on, both resolved ones, and unresolved ones.
  20 //
  21 // If a target depends on another one that hasn't been defined yet, we'll make
  22 // a placeholder BuilderRecord with no item, and try to load the buildfile
  23 // associated with the new item. The item will get filled in when we encounter
  24 // the declaration for the item (or when we're done and realize there are
  25 // undefined items).
  26 //
  27 // You can also have null item pointers when the target is not required for
  28 // the current build (should_generate is false).
  29 class BuilderRecord {
  30  public:
  31   typedef std::set<BuilderRecord*> BuilderRecordSet;
  32
  33   enum ItemType {
  34     ITEM_UNKNOWN,
  35     ITEM_TARGET,
  36     ITEM_CONFIG,
  37     ITEM_TOOLCHAIN
  38   };
  39
  40   BuilderRecord(ItemType type, const Label& label);
  41   ~BuilderRecord();
  42
  43   ItemType type() const { return type_; }
  44   const Label& label() const { return label_; }
  45
  46   // Returns a user-ready name for the given type. e.g. "target".
  47   static const char* GetNameForType(ItemType type);
  48
  49   // Returns true if the given item is of the given type.
  50   static bool IsItemOfType(const Item* item, ItemType type);
  51
  52   // Returns the type enum for the given item.
  53   static ItemType TypeOfItem(const Item* item);
  54
  55   Item* item() { return item_.get(); }
  56   const Item* item() const { return item_.get(); }
  57   void set_item(scoped_ptr<Item> item) { item_ = item.Pass(); }
  58
  59   // Indicates from where this item was originally referenced from that caused
  60   // it to be loaded. For targets for which we encountered the declaration
  61   // before a reference, this will be the empty range.
  62   const ParseNode* originally_referenced_from() const {
  63     return originally_referenced_from_;
  64   }
  65   void set_originally_referenced_from(const ParseNode* pn) {
  66     originally_referenced_from_ = pn;
  67   }
  68
  69   bool should_generate() const { return should_generate_; }
  70   void set_should_generate(bool sg) { should_generate_ = sg; }
  71
  72   bool resolved() const { return resolved_; }
  73   void set_resolved(bool r) { resolved_ = r; }
  74
  75   bool can_resolve() const {
  76     return item_ && unresolved_deps_.empty();
  77   }
  78
  79   // All records this one is depending on.
  80   BuilderRecordSet& all_deps() { return all_deps_; }
  81   const BuilderRecordSet& all_deps() const { return all_deps_; }
  82
  83   // Unresolved records this one is depending on. A subset of all... above.
  84   BuilderRecordSet& unresolved_deps() { return unresolved_deps_; }
  85   const BuilderRecordSet& unresolved_deps() const { return unresolved_deps_; }
  86
  87   // Records that are waiting on this one to be resolved. This is the other
  88   // end of the "unresolved deps" arrow.
  89   BuilderRecordSet& waiting_on_resolution() { return waiting_on_resolution_; }
  90   const BuilderRecordSet& waiting_on_resolution() const {
  91     return waiting_on_resolution_;
  92   }
  93
  94   void AddDep(BuilderRecord* record);
  95
  96  private:
  97   ItemType type_;
  98   Label label_;
  99   scoped_ptr<Item> item_;
 100   const ParseNode* originally_referenced_from_;
 101   bool should_generate_;
 102   bool resolved_;
 103
 104   BuilderRecordSet all_deps_;
 105   BuilderRecordSet unresolved_deps_;
 106   BuilderRecordSet waiting_on_resolution_;
 107
 108   DISALLOW_COPY_AND_ASSIGN(BuilderRecord);
 109 };
 110
 111 #endif  // TOOLS_GN_BUILDER_RECORD_H_