Add worker_threads setting

orotool.conf

@@ -1,2 +1,3 @@
 [main]
 db_path=originsro.db3
+worker_threads=3

src/app_config.cpp

@@ -19,6 +19,11 @@
 #include "orotool_config.hpp"
 #include <fstream>
 #include <string>
+#include <string_view>
+#include <thread>
+#include <algorithm>
+#include <stdexcept>
+#include <iostream>
 
 namespace duck {
 
@@ -28,6 +33,28 @@ namespace {
 		input >> std::noskipws;
 		return { std::istream_iterator<char>(input), std::istream_iterator<char>() };
 	}
+
+	std::string_view value_ifp (
+		const kamokan::IniFile& ini,
+		std::string_view section,
+		std::string_view key,
+		std::string_view def,
+		bool allow_empty
+	) {
+		const auto& map = ini.parsed();
+		auto it_section = map.find(section);
+		if (map.end() == it_section)
+			return def;
+
+		auto it_setting = it_section->second.find(key);
+		if (it_section->second.end() == it_setting)
+			return def;
+
+		if (not allow_empty and it_setting->second.empty())
+			return def;
+		else
+			return it_setting->second;
+	}
 } //unnamed namespace
 
 AppConfig::AppConfig() :
@@ -38,15 +65,27 @@ AppConfig::AppConfig() :
 AppConfig::~AppConfig() noexcept = default;
 
 std::string_view AppConfig::db_path() const {
-	const auto& map = m_ini.parsed();
-	auto it_section = map.find("main");
-	if (map.end() == it_section)
-		return g_def_sqlite_db_name;
+	return value_ifp(m_ini, "main", "db_path", g_def_sqlite_db_name, false);
+}
 
-	auto it_setting = it_section->second.find("db_path");
-	if (it_section->second.end() == it_setting)
-		return g_def_sqlite_db_name;
-	return it_setting->second;
+std::size_t AppConfig::worker_threads() const {
+	std::string_view opt_name("worker_threads");
+
+	std::string_view val = value_ifp(m_ini, "main", opt_name, g_def_worker_threads, false);
+	if (val == "max") {
+		return std::max(3U, std::thread::hardware_concurrency()) - 1;
+	}
+	else {
+		try {
+			const std::size_t num = std::stoul(std::string(val.data(), val.size()));
+			const std::size_t hard_max = 4U * std::thread::hardware_concurrency();
+			return std::max<std::size_t>(2U, std::min(num, hard_max));
+		}
+		catch (const std::logic_error& err) {
+			std::cerr << "Error reading setting " << opt_name << ": " << err.what() << '\n';
+			return std::stoul(g_def_worker_threads);
+		}
+	}
 }
 
 } //namespace duck

src/app_config.hpp

@@ -19,6 +19,7 @@
 
 #include "ini_file.hpp"
 #include <string_view>
+#include <cstddef>
 
 namespace duck {
 
@@ -28,6 +29,7 @@ public:
 	~AppConfig() noexcept;
 
 	std::string_view db_path() const;
+	std::size_t worker_threads() const;
 
 private:
 	kamokan::IniFile m_ini;

src/config.hpp.in

@@ -22,5 +22,6 @@ namespace duck {
 constexpr const char g_base_url[] = @BASE_URL@;
 constexpr const char g_config_file_path[] = @CONFIG_FILE_PATH@;
 constexpr const char g_def_sqlite_db_name[] = @DEF_SQLITE_DB_NAME@;
+constexpr const char g_def_worker_threads[] = "2";
 
 } //namespace duck

src/evloop.cpp

@@ -43,12 +43,11 @@ void join(roar11::ThreadPool& pool) {
 
 } //unnamed namespace
 
-void test(oro::Api* api, oro::OriginsDB* db) {
+void test(oro::Api* api, oro::OriginsDB* db, std::size_t thread_count) {
 	typedef TimerOroApi<&oro::Api::market_list> TimerShops;
 	typedef TimerOroApi<&oro::Api::items_list> TimerItems;
 	typedef TimerOroApi<&oro::Api::items_icons> TimerIcons;
 
-	const std::size_t thread_count = 2U; //std::min(std::max(3U, std::thread::hardware_concurrency()) - 1, 4U);
 	std::cout << "Running with " << thread_count << " worker threads\n";
 	roar11::ThreadPool pool(thread_count);
 	eve::Eventia worker;

src/evloop.hpp

@@ -17,6 +17,8 @@
 
 #pragma once
 
+#include <cstddef>
+
 namespace oro {
 	class Api;
 	class OriginsDB;
@@ -24,6 +26,6 @@ namespace oro {
 
 namespace duck {
 
-void test(oro::Api* api, oro::OriginsDB* db);
+void test(oro::Api* api, oro::OriginsDB* db, std::size_t thread_count);
 
 } //namespace duck

src/main.cpp

@@ -44,7 +44,7 @@ int main(int argc, char* argv[]) {
 
 	duck::AppConfig app_conf;
 	oro::OriginsDB db(app_conf.db_path());
-	duck::test(&oro_api, &db);
+	duck::test(&oro_api, &db, app_conf.worker_threads());
 
 /*
 	{