GYP generator for GN

tools/gn/setup.h

 // 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.
 
 #ifndef TOOLS_GN_SETUP_H_
 #define TOOLS_GN_SETUP_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "tools/gn/build_settings.h"
 #include "tools/gn/scheduler.h"
 #include "tools/gn/scope.h"
 #include "tools/gn/settings.h"
 #include "tools/gn/token.h"
 #include "tools/gn/toolchain.h"
 
 class CommandLine;
 class InputFile;
 class ParseNode;
 
 extern const char kDotfile_Help[];
 
+// Base class for code shared between Setup and DependentSetup.
+class CommonSetup {
+ public:
+  virtual ~CommonSetup();
+
+  // When true (the default), Run() will check for unresolved dependencies and
+  // cycles upon completion. When false, such errors will be ignored.
+  void set_check_for_bad_items(bool s) { check_for_bad_items_ = s; }
+
+  BuildSettings& build_settings() { return build_settings_; }
+
+ protected:
+  CommonSetup();
+  CommonSetup(const CommonSetup& other);
+
+  // Performs the two sets of operations to run the generation before and after
+  // the message loop is run.
+  void RunPreMessageLoop();
+  bool RunPostMessageLoop();
+
+ protected:
+  BuildSettings build_settings_;
+
+  bool check_for_bad_items_;
+
+ private:
+  CommonSetup& operator=(const CommonSetup& other);  // Disallow.
+};
+
 // Helper class to setup the build settings and environment for the various
 // commands to run.
-class Setup {
+class Setup : public CommonSetup {
  public:
   Setup();
-  ~Setup();
+  virtual ~Setup();
 
   // Configures the build for the current command line. On success returns
   // true. On failure, prints the error and returns false.
   bool DoSetup();
 
-  // When true (the default), Run() will check for unresolved dependencies and
-  // cycles upon completion. When false, such errors will be ignored.
-  void set_check_for_bad_items(bool s) { check_for_bad_items_ = s; }
-
   // Runs the load, returning true on success. On failure, prints the error
-  // and returns false.
+  // and returns false. This includes both RunPreMessageLoop() and
+  // RunPostMessageLoop().
   bool Run();
 
-  BuildSettings& build_settings() { return build_settings_; }
   Scheduler& scheduler() { return scheduler_; }
 
  private:
   // Fills build arguments. Returns true on success.
   bool FillArguments(const CommandLine& cmdline);
 
   // Fills the root directory into the settings. Returns true on success.
   bool FillSourceDir(const CommandLine& cmdline);
 
   // Fills the python path portion of the command line. On failure, sets
   // it to just "python".
   void FillPythonPath();
 
   // Run config file.
   bool RunConfigFile();
 
   bool FillOtherConfig(const CommandLine& cmdline);
 
-  BuildSettings build_settings_;
   Scheduler scheduler_;
 
-  bool check_for_bad_items_;
-
   // These empty settings and toolchain are used to interpret the command line
   // and dot file.
   BuildSettings empty_build_settings_;
   Toolchain empty_toolchain_;
   Settings empty_settings_;
   Scope dotfile_scope_;
 
   // State for invoking the dotfile.
   base::FilePath dotfile_name_;
   scoped_ptr<InputFile> dotfile_input_file_;
   std::vector<Token> dotfile_tokens_;
   scoped_ptr<ParseNode> dotfile_root_;
 
   // State for invoking the command line args. We specifically want to keep
   // this around for the entire run so that Values can blame to the command
   // line when we issue errors about them.
   scoped_ptr<InputFile> args_input_file_;
   std::vector<Token> args_tokens_;
   scoped_ptr<ParseNode> args_root_;
 
   DISALLOW_COPY_AND_ASSIGN(Setup);
 };
 
+// A dependent setup allows one to do more than one build at a time. You would
+// make a dependent setup which clones the state of the main one, make any
+// necessary changes, and then run it.
+//
+// The way to run both at the same time is:
+//   dependent_setup.RunPreMessageLoop();
+//   main_setup.Run();
+//   dependent_setup.RunPostMessageLoop();
+// so that the main setup executes the message loop, but both are run.
+class DependentSetup : public CommonSetup {
+ public:
+  DependentSetup(const Setup& main_setup);
+  virtual ~DependentSetup();
+
+  // These are the two parts of Run() in the regular setup, not including the
+  // call to actually run the message loop.
+  void RunPreMessageLoop();
+  bool RunPostMessageLoop();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DependentSetup);
+};
+
 #endif  // TOOLS_GN_SETUP_H_