OpenTTD-patches/src/driver.h
2019-11-10 17:59:20 +00:00

141 lines
3.9 KiB
C++

/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/** @file driver.h Base for all drivers (video, sound, music, etc). */
#ifndef DRIVER_H
#define DRIVER_H
#include "core/enum_type.hpp"
#include "core/string_compare_type.hpp"
#include <map>
const char *GetDriverParam(const char * const *parm, const char *name);
bool GetDriverParamBool(const char * const *parm, const char *name);
int GetDriverParamInt(const char * const *parm, const char *name, int def);
/** A driver for communicating with the user. */
class Driver {
public:
/**
* Start this driver.
* @param parm Parameters passed to the driver.
* @return nullptr if everything went okay, otherwise an error message.
*/
virtual const char *Start(const char * const *parm) = 0;
/**
* Stop this driver.
*/
virtual void Stop() = 0;
virtual ~Driver() { }
/** The type of driver */
enum Type {
DT_BEGIN = 0, ///< Helper for iteration
DT_MUSIC = 0, ///< A music driver, needs to be before sound to properly shut down extmidi forked music players
DT_SOUND, ///< A sound driver
DT_VIDEO, ///< A video driver
DT_END, ///< Helper for iteration
};
/**
* Get the name of this driver.
* @return The name of the driver.
*/
virtual const char *GetName() const = 0;
};
DECLARE_POSTFIX_INCREMENT(Driver::Type)
/** Base for all driver factories. */
class DriverFactoryBase {
private:
friend class MusicDriver;
friend class SoundDriver;
friend class VideoDriver;
Driver::Type type; ///< The type of driver.
int priority; ///< The priority of this factory.
const char *name; ///< The name of the drivers of this factory.
const char *description; ///< The description of this driver.
typedef std::map<const char *, DriverFactoryBase *, StringCompare> Drivers; ///< Type for a map of drivers.
/**
* Get the map with drivers.
*/
static Drivers &GetDrivers()
{
static Drivers &s_drivers = *new Drivers();
return s_drivers;
}
/**
* Get the active driver for the given type.
* @param type The type to get the driver for.
* @return The active driver.
*/
static Driver **GetActiveDriver(Driver::Type type)
{
static Driver *s_driver[3] = { nullptr, nullptr, nullptr };
return &s_driver[type];
}
/**
* Get the driver type name.
* @param type The type of driver to get the name of.
* @return The name of the type.
*/
static const char *GetDriverTypeName(Driver::Type type)
{
static const char * const driver_type_name[] = { "music", "sound", "video" };
return driver_type_name[type];
}
static bool SelectDriverImpl(const char *name, Driver::Type type);
protected:
DriverFactoryBase(Driver::Type type, int priority, const char *name, const char *description);
virtual ~DriverFactoryBase();
public:
/**
* Shuts down all active drivers
*/
static void ShutdownDrivers()
{
for (Driver::Type dt = Driver::DT_BEGIN; dt < Driver::DT_END; dt++) {
Driver *driver = *GetActiveDriver(dt);
if (driver != nullptr) driver->Stop();
}
}
static void SelectDriver(const char *name, Driver::Type type);
static char *GetDriversInfo(char *p, const char *last);
/**
* Get a nice description of the driver-class.
* @return The description.
*/
const char *GetDescription() const
{
return this->description;
}
/**
* Create an instance of this driver-class.
* @return The instance.
*/
virtual Driver *CreateInstance() const = 0;
};
#endif /* DRIVER_H */