https://github.com/scummvm/scummvm
Tip revision: 3b11bd6abfcad23a68adb57915950a04c03075f6 authored by Chris Apers on 23 December 2004, 20:20:35 UTC
Done.
Done.
Tip revision: 3b11bd6
plugins.cpp
/* ScummVM - Scumm Interpreter
* Copyright (C) 2001 Ludvig Strigeus
* Copyright (C) 2001-2004 The ScummVM project
*
* This program 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; either version 2
* of the License, or (at your option) any later version.
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* $Header$
*
*/
#include "stdafx.h"
#include "backends/fs/fs.h"
#include "base/gameDetector.h"
#include "base/plugins.h"
#include "base/engine.h"
#include "common/util.h"
/** Type of factory functions which make new Engine objects. */
typedef Engine *(*EngineFactory)(GameDetector *detector, OSystem *syst);
typedef const char *(*NameFunc)();
typedef GameList (*TargetListFunc)();
typedef DetectedGameList (*DetectFunc)(const FSList &fslist);
#ifdef DYNAMIC_MODULES
#ifdef UNIX
#include <dlfcn.h>
#define DYNAMIC_PLUGIN_PATH(name) (name "/lib" name ".so")
#else
#ifdef __DC__
#include "dcloader.h"
#define DYNAMIC_PLUGIN_PATH(name) (name ".plg")
#else
#error No support for loading plugins on non-unix systems at this point!
#endif
#endif
#endif
#pragma mark -
GameSettings Plugin::findGame(const char *gameName) const {
// Find the GameSettings for this game
assert(gameName);
GameList games = getSupportedGames();
GameSettings result = {NULL, NULL, 0};
for (GameList::iterator g = games.begin(); g != games.end(); ++g) {
if (!scumm_stricmp(g->name, gameName)) {
result = *g;
break;
}
}
return result;
}
#pragma mark -
class StaticPlugin : public Plugin {
const char *_name;
EngineFactory _ef;
DetectFunc _df;
GameList _games;
public:
StaticPlugin(const char *name, GameList games, EngineFactory ef, DetectFunc df)
: _name(name), _ef(ef), _df(df), _games(games) {
}
const char *getName() const { return _name; }
Engine *createInstance(GameDetector *detector, OSystem *syst) const {
return (*_ef)(detector, syst);
}
GameList getSupportedGames() const { return _games; }
DetectedGameList detectGames(const FSList &fslist) const {
return (*_df)(fslist);
}
};
#pragma mark -
#ifdef DYNAMIC_MODULES
class DynamicPlugin : public Plugin {
void *_dlHandle;
Common::String _filename;
Common::String _name;
EngineFactory _ef;
DetectFunc _df;
GameList _games;
void *findSymbol(const char *symbol);
public:
DynamicPlugin(const char *filename)
: _dlHandle(0), _filename(filename), _ef(0), _df(0), _games() {}
const char *getName() const { return _name.c_str(); }
Engine *createInstance(GameDetector *detector, OSystem *syst) const {
assert(_ef);
return (*_ef)(detector, syst);
}
GameList getSupportedGames() const { return _games; }
DetectedGameList detectGames(const FSList &fslist) const {
assert(_df);
return (*_df)(fslist);
}
bool loadPlugin();
void unloadPlugin();
};
void *DynamicPlugin::findSymbol(const char *symbol) {
#if defined(UNIX)||defined(__DC__)
void *func = dlsym(_dlHandle, symbol);
if (!func)
warning("Failed loading symbol '%s' from plugin '%s' (%s)", symbol, _filename.c_str(), dlerror());
return func;
#else
#error TODO
#endif
}
bool DynamicPlugin::loadPlugin() {
assert(!_dlHandle);
_dlHandle = dlopen(_filename.c_str(), RTLD_LAZY);
if (!_dlHandle) {
warning("Failed loading plugin '%s' (%s)", _filename.c_str(), dlerror());
return false;
}
// Query the plugin's name
NameFunc nameFunc = (NameFunc)findSymbol("PLUGIN_name");
if (!nameFunc) {
unloadPlugin();
return false;
}
_name = nameFunc();
// Query the plugin for the targets it supports
TargetListFunc gameListFunc = (TargetListFunc)findSymbol("PLUGIN_getSupportedGames");
if (!gameListFunc) {
unloadPlugin();
return false;
}
_games = gameListFunc();
// Retrieve the factory function
_ef = (EngineFactory)findSymbol("PLUGIN_createEngine");
if (!_ef) {
unloadPlugin();
return false;
}
// Retrieve the detector function
_df = (DetectFunc)findSymbol("PLUGIN_detectGames");
if (!_df) {
unloadPlugin();
return false;
}
#ifdef __DC__
dlforgetsyms(_dlHandle);
#endif
return true;
}
void DynamicPlugin::unloadPlugin() {
if (_dlHandle) {
if (dlclose(_dlHandle) != 0)
warning("Failed unloading plugin '%s' (%s)", _filename.c_str(), dlerror());
}
}
#endif // DYNAMIC_MODULES
#pragma mark -
PluginManager::PluginManager() {
}
PluginManager::~PluginManager() {
// Explicitly unload all loaded plugins
unloadPlugins();
}
void PluginManager::loadPlugins() {
#ifdef DYNAMIC_MODULES
// Load dynamic plugins
// TODO... this is right now just a nasty hack.
// This should search one or multiple directories for all plugins it can
// find (to this end, we maybe should use a special prefix/suffix; e.g.
// instead of libscumm.so, use scumm.engine or scumm.plugin etc.).
//
// The list of directories to search could be e.g.:
// User specified (via config file), ".", "./plugins", "$(prefix)/lib".
//
// We also need to add code which ensures what we are looking at is
// a) a ScummVM engine and b) matches the version of the executable.
// Hence one more symbol should be exported by plugins which returns
// the "ABI" version the plugin was built for, and we can compare that
// to the ABI version of the executable.
#define LOAD_MODULE(name, NAME) \
tryLoadPlugin(new DynamicPlugin(DYNAMIC_PLUGIN_PATH(name)));
#else
// "Loader" for the static plugins
#define LOAD_MODULE(name, NAME) \
tryLoadPlugin(new StaticPlugin(name, Engine_##NAME##_gameList(), Engine_##NAME##_create, Engine_##NAME##_detectGames));
#endif
// Load all plugins.
// Right now the list is hardcoded. On the long run, of course it should
// automatically be determined.
#ifndef DISABLE_SCUMM
LOAD_MODULE("scumm", SCUMM);
#endif
#ifndef DISABLE_SIMON
LOAD_MODULE("simon", SIMON);
#endif
#ifndef DISABLE_SKY
LOAD_MODULE("sky", SKY);
#endif
#ifndef DISABLE_SWORD1
LOAD_MODULE("sword1", SWORD1);
#endif
#ifndef DISABLE_SWORD2
LOAD_MODULE("sword2", SWORD2);
#endif
#ifndef DISABLE_QUEEN
LOAD_MODULE("queen", QUEEN);
#endif
#ifndef DISABLE_KYRA
LOAD_MODULE("kyra", KYRA);
#endif
#ifndef DISABLE_SAGA
LOAD_MODULE("saga", SAGA);
#endif
}
void PluginManager::unloadPlugins() {
unloadPluginsExcept(NULL);
}
void PluginManager::unloadPluginsExcept(const Plugin *plugin) {
Plugin *found = NULL;
uint i;
for (i = 0; i < _plugins.size(); i++) {
if (_plugins[i] == plugin) {
found = _plugins[i];
} else {
_plugins[i]->unloadPlugin();
delete _plugins[i];
}
}
_plugins.clear();
if (found != NULL) {
_plugins.push_back(found);
}
}
bool PluginManager::tryLoadPlugin(Plugin *plugin) {
assert(plugin);
// Try to load the plugin
if (plugin->loadPlugin()) {
// If successful, add it to the list of known plugins and return.
_plugins.push_back(plugin);
return true;
} else {
// Failed to load the plugin
delete plugin;
return false;
}
}
DetectedGameList PluginManager::detectGames(const FSList &fslist) const {
DetectedGameList candidates;
// Iterate over all known games and for each check if it might be
// the game in the presented directory.
PluginList::const_iterator iter;
for (iter = _plugins.begin(); iter != _plugins.end(); ++iter) {
candidates.push_back((*iter)->detectGames(fslist));
}
return candidates;
}