blob: 27368ff82d2d9766fa110ab325b9ae71d70f9a25 [file] [log] [blame]
// Copyright (c) 2016 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 "gn/json_project_writer.h"
#include <algorithm>
#include <fstream>
#include <memory>
#include <unordered_map>
#include <vector>
#include "base/command_line.h"
#include "base/files/file_path.h"
#include "base/files/file_util.h"
#include "base/json/json_writer.h"
#include "base/json/string_escape.h"
#include "base/strings/string_number_conversions.h"
#include "gn/builder.h"
#include "gn/commands.h"
#include "gn/deps_iterator.h"
#include "gn/desc_builder.h"
#include "gn/exec_process.h"
#include "gn/filesystem_utils.h"
#include "gn/scheduler.h"
#include "gn/settings.h"
#include "gn/string_output_buffer.h"
// Structure of JSON output file
// {
// "build_settings" : {
// "root_path" : "absolute path of project root",
// "build_dir" : "build directory (project relative)",
// "default_toolchain" : "name of default toolchain"
// }
// "targets" : {
// "target x full label" : { target x properties },
// "target y full label" : { target y properties },
// ...
// }
// }
// See desc_builder.cc for overview of target properties
namespace {
void AddTargetDependencies(const Target* target, TargetSet* deps) {
for (const auto& pair : target->GetDeps(Target::DEPS_LINKED)) {
if (deps->add(pair.ptr)) {
AddTargetDependencies(pair.ptr, deps);
}
}
}
// Filters targets according to filter string; Will also recursively
// add dependent targets.
bool FilterTargets(const BuildSettings* build_settings,
std::vector<const Target*>& all_targets,
std::vector<const Target*>* targets,
const std::string& dir_filter_string,
Err* err) {
if (dir_filter_string.empty()) {
*targets = all_targets;
} else {
targets->reserve(all_targets.size());
std::vector<LabelPattern> filters;
if (!commands::FilterPatternsFromString(build_settings, dir_filter_string,
&filters, err)) {
return false;
}
commands::FilterTargetsByPatterns(all_targets, filters, targets);
TargetSet target_set(targets->begin(), targets->end());
for (const auto* target : *targets)
AddTargetDependencies(target, &target_set);
targets->clear();
targets->insert(targets->end(), target_set.begin(), target_set.end());
}
// Sort the list of targets per-label to get a consistent ordering of them
// in the generated project (and thus stability of the file generated).
std::sort(targets->begin(), targets->end(),
[](const Target* a, const Target* b) {
return a->label().name() < b->label().name();
});
return true;
}
bool InvokePython(const BuildSettings* build_settings,
const base::FilePath& python_script_path,
const std::string& python_script_extra_args,
const base::FilePath& output_path,
bool quiet,
Err* err) {
const base::FilePath& python_path = build_settings->python_path();
base::CommandLine cmdline(python_path);
cmdline.AppendArg("--");
cmdline.AppendArgPath(python_script_path);
cmdline.AppendArgPath(output_path);
if (!python_script_extra_args.empty()) {
cmdline.AppendArg(python_script_extra_args);
}
base::FilePath startup_dir =
build_settings->GetFullPath(build_settings->build_dir());
std::string output;
std::string stderr_output;
int exit_code = 0;
if (!internal::ExecProcess(cmdline, startup_dir, &output, &stderr_output,
&exit_code)) {
*err =
Err(Location(), "Could not execute python.",
"I was trying to execute \"" + FilePathToUTF8(python_path) + "\".");
return false;
}
if (!quiet) {
printf("%s", output.c_str());
fprintf(stderr, "%s", stderr_output.c_str());
}
if (exit_code != 0) {
*err = Err(Location(), "Python has quit with exit code " +
base::IntToString(exit_code) + ".");
return false;
}
return true;
}
} // namespace
bool JSONProjectWriter::RunAndWriteFiles(
const BuildSettings* build_settings,
const Builder& builder,
const std::string& file_name,
const std::string& exec_script,
const std::string& exec_script_extra_args,
const std::string& dir_filter_string,
bool quiet,
Err* err) {
SourceFile output_file = build_settings->build_dir().ResolveRelativeFile(
Value(nullptr, file_name), err);
if (output_file.is_null()) {
return false;
}
base::FilePath output_path = build_settings->GetFullPath(output_file);
std::vector<const Target*> all_targets = builder.GetAllResolvedTargets();
std::vector<const Target*> targets;
if (!FilterTargets(build_settings, all_targets, &targets, dir_filter_string,
err)) {
return false;
}
StringOutputBuffer json = GenerateJSON(build_settings, targets);
if (!json.ContentsEqual(output_path)) {
if (!json.WriteToFile(output_path, err)) {
return false;
}
if (!exec_script.empty()) {
SourceFile script_file;
if (exec_script[0] != '/') {
// Relative path, assume the base is in build_dir.
script_file = build_settings->build_dir().ResolveRelativeFile(
Value(nullptr, exec_script), err);
if (script_file.is_null()) {
return false;
}
} else {
script_file = SourceFile(exec_script);
}
base::FilePath script_path = build_settings->GetFullPath(script_file);
return InvokePython(build_settings, script_path, exec_script_extra_args,
output_path, quiet, err);
}
}
return true;
}
namespace {
// NOTE: Intentional macro definition allows compile-time string concatenation.
// (see usage below).
#if defined(OS_WINDOWS)
#define LINE_ENDING "\r\n"
#else
#define LINE_ENDING "\n"
#endif
// Helper class to output a, potentially very large, JSON file to a
// StringOutputBuffer. Note that sorting the keys, if desired, is left to
// the user (unlike base::JSONWriter). This allows rendering to be performed
// in series of incremental steps. Usage is:
//
// 1) Create instance, passing a StringOutputBuffer reference as the
// destination.
//
// 2) Add keys and values using one of the following:
//
// a) AddString(key, string_value) to add one string value.
//
// b) BeginList(key), AddListItem(), EndList() to add a string list.
// NOTE: Only lists of strings are supported here.
//
// c) BeginDict(key), ... add other keys, followed by EndDict() to add
// a dictionary key.
//
// 3) Call Close() or destroy the instance to finalize the output.
//
class SimpleJSONWriter {
public:
// Constructor.
SimpleJSONWriter(StringOutputBuffer& out) : out_(out) {
out_ << "{" LINE_ENDING;
SetIndentation(1u);
}
// Destructor.
~SimpleJSONWriter() { Close(); }
// Closing finalizes the output.
void Close() {
if (indentation_ > 0) {
DCHECK(indentation_ == 1u);
if (comma_.size())
out_ << LINE_ENDING;
out_ << "}" LINE_ENDING;
SetIndentation(0);
}
}
// Add new string-valued key.
void AddString(std::string_view key, std::string_view value) {
if (comma_.size()) {
out_ << comma_;
}
AddMargin() << Escape(key) << ": " << Escape(value);
comma_ = "," LINE_ENDING;
}
// Begin a new list. Must be followed by zero or more AddListItem() calls,
// then by EndList().
void BeginList(std::string_view key) {
if (comma_.size())
out_ << comma_;
AddMargin() << Escape(key) << ": [ ";
comma_ = {};
}
// Add a new list item. For now only string values are supported.
void AddListItem(std::string_view item) {
if (comma_.size())
out_ << comma_;
out_ << Escape(item);
comma_ = ", ";
}
// End current list.
void EndList() {
out_ << " ]";
comma_ = "," LINE_ENDING;
}
// Begin new dictionaary. Must be followed by zero or more other key
// additions, then a call to EndDict().
void BeginDict(std::string_view key) {
if (comma_.size())
out_ << comma_;
AddMargin() << Escape(key) << ": {";
SetIndentation(indentation_ + 1);
comma_ = LINE_ENDING;
}
// End current dictionary.
void EndDict() {
if (comma_.size())
out_ << LINE_ENDING;
SetIndentation(indentation_ - 1);
AddMargin() << "}";
comma_ = "," LINE_ENDING;
}
// Add a dictionary-valued key, whose value is already formatted as a valid
// JSON string. Useful to insert the output of base::JSONWriter::Write()
// into the target buffer.
void AddJSONDict(std::string_view key, std::string_view json) {
if (comma_.size())
out_ << comma_;
AddMargin() << Escape(key) << ": ";
if (json.empty()) {
out_ << "{ }";
} else {
DCHECK(json[0] == '{');
bool first_line = true;
do {
size_t line_end = json.find('\n');
// NOTE: Do not add margin if original input line is empty.
// This needs to deal with CR/LF which are part of |json| on Windows
// only, due to the way base::JSONWriter::Write() is implemented.
bool line_empty = (line_end == 0 || (line_end == 1 && json[0] == '\r'));
if (!first_line && !line_empty)
AddMargin();
if (line_end == std::string_view::npos) {
out_ << json;
comma_ = {};
return;
}
// Important: do not add the final newline.
out_ << json.substr(
0, (line_end == json.size() - 1) ? line_end : line_end + 1);
json.remove_prefix(line_end + 1);
first_line = false;
} while (!json.empty());
}
comma_ = "," LINE_ENDING;
}
private:
// Return the JSON-escape version of |str|.
static std::string Escape(std::string_view str) {
std::string result;
base::EscapeJSONString(str, true, &result);
return result;
}
// Adjust indentation level.
void SetIndentation(size_t indentation) { indentation_ = indentation; }
// Append margin, and return reference to output buffer.
StringOutputBuffer& AddMargin() const {
static const char kMargin[17] = " ";
size_t margin_len = indentation_ * 3;
while (margin_len > 0) {
size_t span = (margin_len > 16u) ? 16u : margin_len;
out_.Append(kMargin, span);
margin_len -= span;
}
return out_;
}
size_t indentation_ = 0;
std::string_view comma_;
StringOutputBuffer& out_;
};
} // namespace
StringOutputBuffer JSONProjectWriter::GenerateJSON(
const BuildSettings* build_settings,
std::vector<const Target*>& all_targets) {
Label default_toolchain_label;
if (!all_targets.empty())
default_toolchain_label =
all_targets[0]->settings()->default_toolchain_label();
StringOutputBuffer out;
// Sort the targets according to their human visible labels first.
std::unordered_map<const Target*, std::string> target_labels;
for (const Target* target : all_targets) {
target_labels[target] =
target->label().GetUserVisibleName(default_toolchain_label);
}
std::vector<const Target*> sorted_targets(all_targets.begin(),
all_targets.end());
std::sort(sorted_targets.begin(), sorted_targets.end(),
[&target_labels](const Target* a, const Target* b) {
return target_labels[a] < target_labels[b];
});
SimpleJSONWriter json_writer(out);
// IMPORTANT: Keep the keys sorted when adding them to |json_writer|.
json_writer.BeginDict("build_settings");
{
json_writer.AddString("build_dir", build_settings->build_dir().value());
json_writer.AddString("default_toolchain",
default_toolchain_label.GetUserVisibleName(false));
json_writer.BeginList("gen_input_files");
// Other files read by the build.
std::vector<base::FilePath> other_files = g_scheduler->GetGenDependencies();
const InputFileManager* input_file_manager =
g_scheduler->input_file_manager();
VectorSetSorter<base::FilePath> sorter(
input_file_manager->GetInputFileCount() + other_files.size());
input_file_manager->AddAllPhysicalInputFileNamesToVectorSetSorter(&sorter);
sorter.Add(other_files.begin(), other_files.end());
std::string build_path = FilePathToUTF8(build_settings->root_path());
auto item_callback = [&json_writer,
&build_path](const base::FilePath& input_file) {
std::string file;
if (MakeAbsolutePathRelativeIfPossible(
build_path, FilePathToUTF8(input_file), &file)) {
json_writer.AddListItem(file);
}
};
sorter.IterateOver(item_callback);
json_writer.EndList(); // gen_input_files
json_writer.AddString("root_path", build_settings->root_path_utf8());
}
json_writer.EndDict(); // build_settings
std::map<Label, const Toolchain*> toolchains;
json_writer.BeginDict("targets");
{
for (const auto* target : sorted_targets) {
auto description =
DescBuilder::DescriptionForTarget(target, "", false, false, false);
// Outputs need to be asked for separately.
auto outputs = DescBuilder::DescriptionForTarget(target, "source_outputs",
false, false, false);
base::DictionaryValue* outputs_value = nullptr;
if (outputs->GetDictionary("source_outputs", &outputs_value) &&
!outputs_value->empty()) {
description->MergeDictionary(outputs.get());
}
std::string json_dict;
base::JSONWriter::WriteWithOptions(*description.get(),
base::JSONWriter::OPTIONS_PRETTY_PRINT,
&json_dict);
json_writer.AddJSONDict(target_labels[target], json_dict);
toolchains[target->toolchain()->label()] = target->toolchain();
}
}
json_writer.EndDict(); // targets
json_writer.BeginDict("toolchains");
{
for (const auto& tool_chain_kv : toolchains) {
base::Value toolchain{base::Value::Type::DICTIONARY};
const auto& tools = tool_chain_kv.second->tools();
for (const auto& tool_kv : tools) {
// Do not list builtin tools
if (tool_kv.second->AsBuiltin())
continue;
base::Value tool_info{base::Value::Type::DICTIONARY};
auto setIfNotEmptry = [&](const auto& key, const auto& value) {
if (value.size())
tool_info.SetKey(key, base::Value{value});
};
auto setSubstitutionList = [&](const auto& key,
const SubstitutionList& list) {
if (list.list().empty())
return;
base::Value values{base::Value::Type::LIST};
for (const auto& v : list.list())
values.GetList().emplace_back(base::Value{v.AsString()});
tool_info.SetKey(key, std::move(values));
};
const auto& tool = tool_kv.second;
setIfNotEmptry("command", tool->command().AsString());
setIfNotEmptry("command_launcher", tool->command_launcher());
setIfNotEmptry("default_output_extension",
tool->default_output_extension());
setIfNotEmptry("default_output_dir",
tool->default_output_dir().AsString());
setIfNotEmptry("depfile", tool->depfile().AsString());
setIfNotEmptry("description", tool->description().AsString());
setIfNotEmptry("framework_switch", tool->framework_switch());
setIfNotEmptry("weak_framework_switch", tool->weak_framework_switch());
setIfNotEmptry("framework_dir_switch", tool->framework_dir_switch());
setIfNotEmptry("lib_switch", tool->lib_switch());
setIfNotEmptry("lib_dir_switch", tool->lib_dir_switch());
setIfNotEmptry("linker_arg", tool->linker_arg());
setSubstitutionList("outputs", tool->outputs());
setSubstitutionList("partial_outputs", tool->partial_outputs());
setSubstitutionList("runtime_outputs", tool->runtime_outputs());
setIfNotEmptry("output_prefix", tool->output_prefix());
toolchain.SetKey(tool_kv.first, std::move(tool_info));
}
std::string json_dict;
base::JSONWriter::WriteWithOptions(
toolchain, base::JSONWriter::OPTIONS_PRETTY_PRINT, &json_dict);
json_writer.AddJSONDict(tool_chain_kv.first.GetUserVisibleName(false), json_dict);
}
}
json_writer.EndDict(); // toolchains
json_writer.Close();
return out;
}
std::string JSONProjectWriter::RenderJSON(
const BuildSettings* build_settings,
std::vector<const Target*>& all_targets) {
StringOutputBuffer storage = GenerateJSON(build_settings, all_targets);
return storage.str();
}