blob: 6852c30930076f5346d021f431cec179e4fd2a4b [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.
#ifndef TOOLS_GN_ARGS_H_
#define TOOLS_GN_ARGS_H_
#include "base/basictypes.h"
#include "base/containers/hash_tables.h"
#include "base/synchronization/lock.h"
#include "tools/gn/err.h"
#include "tools/gn/scope.h"
extern const char kBuildArgs_Help[];
// Manages build arguments. It stores the global arguments specified on the
// command line, and sets up the root scope with the proper values.
// This class tracks accesses so we can report errors about unused variables.
// The use case is if the user specifies an override on the command line, but
// no buildfile actually uses that variable. We want to be able to report that
// the argument was unused.
class Args {
Args(const Args& other);
// Specifies overrides of the build arguments. These are normally specified
// on the command line.
void AddArgOverride(const char* name, const Value& value);
void AddArgOverrides(const Scope::KeyValueMap& overrides);
// Returns the value corresponding to the given argument name, or NULL if no
// argument is set.
const Value* GetArgOverride(const char* name) const;
// Gets all overrides set on the build.
Scope::KeyValueMap GetAllOverrides() const;
// Sets up the root scope for a toolchain. This applies the default system
// flags, then any overrides stored in this object, then applies any
// toolchain overrides specified in the argument.
void SetupRootScope(Scope* dest,
const Scope::KeyValueMap& toolchain_overrides) const;
// Sets up the given scope with arguments passed in.
// If the values specified in the args are not already set, the values in
// the args list will be used (which are assumed to be the defaults), but
// they will not override the system defaults or the current overrides.
// All args specified in the input will be marked as "used".
// On failure, the err will be set and it will return false.
bool DeclareArgs(const Scope::KeyValueMap& args,
Scope* scope_to_set,
Err* err) const;
// Checks to see if any of the overrides ever used were never declared as
// arguments. If there are, this returns false and sets the error.
bool VerifyAllOverridesUsed(Err* err) const;
// Like VerifyAllOverridesUsed but takes the lists of overrides specified and
// parameters declared.
static bool VerifyAllOverridesUsed(
const Scope::KeyValueMap& overrides,
const Scope::KeyValueMap& declared_arguments,
Err* err);
// Adds all declared arguments to the given output list. If the values exist
// in the list already, their values will be overwriten, but other values
// already in the list will remain.
void MergeDeclaredArguments(Scope::KeyValueMap* dest) const;
// Sets the default config based on the current system.
void SetSystemVarsLocked(Scope* scope) const;
// Sets the given vars on the given scope.
void ApplyOverridesLocked(const Scope::KeyValueMap& values,
Scope* scope) const;
void SaveOverrideRecordLocked(const Scope::KeyValueMap& values) const;
// Since this is called during setup which we assume is single-threaded,
// this is not protected by the lock. It should be set only during init.
Scope::KeyValueMap overrides_;
mutable base::Lock lock_;
// Maintains a list of all overrides we've ever seen. This is the main
// |overrides_| as well as toolchain overrides. Tracking this allows us to
// check for overrides that were specified but never used.
mutable Scope::KeyValueMap all_overrides_;
// Tracks all variables declared in any buildfile. This is so we can see if
// the user set variables on the command line that are not used anywhere.
mutable Scope::KeyValueMap declared_arguments_;
Args& operator=(const Args& other); // Disallow assignment.
#endif // TOOLS_GN_ARGS_H_