blob: 36bcbc5ac6cd0684ca88c70cd8ab574b77d512b1 [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 <iostream>
#include <sstream>
#include "base/file_util.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "tools/gn/err.h"
#include "tools/gn/filesystem_utils.h"
#include "tools/gn/functions.h"
#include "tools/gn/input_file.h"
#include "tools/gn/parse_tree.h"
#include "tools/gn/scheduler.h"
namespace functions {
const char kWriteFile[] = "write_file";
const char kWriteFile_HelpShort[] =
"write_file: Write a file to disk.";
const char kWriteFile_Help[] =
"write_file: Write a file to disk.\n"
" write_file(filename, data)\n"
" If data is a list, the list will be written one-item-per-line with no\n"
" quoting or brackets.\n"
" If the file exists and the contents are identical to that being\n"
" written, the file will not be updated. This will prevent unnecessary\n"
" rebuilds of targets that depend on this file.\n"
" TODO(brettw) we probably need an optional third argument to control\n"
" list formatting.\n"
" filename\n"
" Filename to write. This must be within the output directory.\n"
" data:\n"
" The list or string to write.\n";
Value RunWriteFile(Scope* scope,
const FunctionCallNode* function,
const std::vector<Value>& args,
Err* err) {
if (args.size() != 2) {
*err = Err(function->function(), "Wrong number of arguments to write_file",
"I expected two arguments.");
return Value();
// Compute the file name and make sure it's in the output dir.
if (!args[0].VerifyTypeIs(Value::STRING, err))
return Value();
const SourceDir& cur_dir = scope->GetSourceDir();
SourceFile source_file = cur_dir.ResolveRelativeFile(args[0].string_value());
if (!EnsureStringIsInOutputDir(
source_file.value(), args[0], err))
return Value();
// Compute output.
std::ostringstream contents;
if (args[1].type() == Value::LIST) {
const std::vector<Value>& list = args[1].list_value();
for (size_t i = 0; i < list.size(); i++)
contents << list[i].ToString(false) << std::endl;
} else {
contents << args[1].ToString(false);
const std::string& new_contents = contents.str();
base::FilePath file_path =
// Make sure we're not replacing the same contents.
std::string existing_contents;
if (base::ReadFileToString(file_path, &existing_contents) &&
existing_contents == new_contents)
return Value(); // Nothing to do.
// Write file, creating the directory if necessary.
if (!base::CreateDirectory(file_path.DirName())) {
*err = Err(function->function(), "Unable to create directory.",
"I was using \"" + FilePathToUTF8(file_path.DirName()) + "\".");
return Value();
int int_size = static_cast<int>(new_contents.size());
if (base::WriteFile(file_path, new_contents.c_str(), int_size)
!= int_size) {
*err = Err(function->function(), "Unable to write file.",
"I was writing \"" + FilePathToUTF8(file_path) + "\".");
return Value();
return Value();
} // namespace functions