aboutsummaryrefslogtreecommitdiff
path: root/base/plugins.cpp
blob: 3cc2756d9d85c5f01b5f7a8fd19687354dc27dff (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
/* ScummVM - Scumm Interpreter
 * Copyright (C) 2001  Ludvig Strigeus
 * Copyright (C) 2001-2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/stdafx.h"
#include "backends/fs/fs.h"
#include "base/plugins.h"
#include "base/engine.h"
#include "common/util.h"

/** Type of factory functions which make new Engine objects. */
typedef PluginError (*EngineFactory)(OSystem *syst, Engine **engine);

typedef const char *(*NameFunc)();
typedef GameDescriptor (*GameIDQueryFunc)(const char *gameid);
typedef GameList (*GameIDListFunc)();
typedef DetectedGameList (*DetectFunc)(const FSList &fslist);


#ifdef DYNAMIC_MODULES

#ifdef UNIX
#include <dlfcn.h>
#define PLUGIN_DIRECTORY	"plugins/"
#else
#ifdef __DC__
#include "dcloader.h"
#define PLUGIN_DIRECTORY	"/"
#define PLUGIN_PREFIX		""
#define PLUGIN_SUFFIX		".PLG"
#else
#ifdef _WIN32
#define PLUGIN_DIRECTORY	""
#define PLUGIN_PREFIX		""
#define PLUGIN_SUFFIX		".dll"
#else
#error No support for loading plugins on non-unix systems at this point!
#endif
#endif
#endif

#else

PluginRegistrator::PluginRegistrator(const char *name, GameList games, GameIDQueryFunc qf, EngineFactory ef, DetectFunc df)
	: _name(name), _qf(qf), _ef(ef), _df(df), _games(games) {
	//printf("Automatically registered plugin '%s'\n", name);
}

#endif


#pragma mark -


void DetectedGame::updateDesc(const char *extra) {
	// TODO: The format used here (LANG/PLATFORM/EXTRA) is not set in stone.
	// We may want to change the order (PLATFORM/EXTRA/LANG, anybody?), or
	// the seperator (instead of '/' use ', ' or ' ').
	const bool hasCustomLanguage = (language != Common::UNK_LANG);
	const bool hasCustomPlatform = (platform != Common::kPlatformUnknown);
	const bool hasExtraDesc = (extra && extra[0]);

	// Adapt the description string if custom platform/language is set.
	if (hasCustomLanguage || hasCustomPlatform || hasExtraDesc) {
		description += " (";
		if (hasCustomLanguage)
			description += Common::getLanguageDescription(language);
		if (hasCustomPlatform) {
			if (hasCustomLanguage)
				description += "/";
			description += Common::getPlatformDescription(platform);
		}
		if (hasExtraDesc) {
			if (hasCustomPlatform || hasCustomLanguage)
				description += "/";
			description += extra;
		}
		description += ")";
	}
}


#pragma mark -

#ifndef DYNAMIC_MODULES
class StaticPlugin : public Plugin {
	PluginRegistrator *_plugin;
public:
	StaticPlugin(PluginRegistrator *plugin)
		: _plugin(plugin) {
		assert(_plugin);
	}
	
	~StaticPlugin() {
		delete _plugin;
	}

	const char *getName() const { return _plugin->_name; }

	PluginError createInstance(OSystem *syst, Engine **engine) const {
		assert(_plugin->_ef);
		return (*_plugin->_ef)(syst, engine);
	}

	GameList getSupportedGames() const { return _plugin->_games; }

	GameDescriptor findGame(const char *gameid) const {
		assert(_plugin->_qf);
		return (*_plugin->_qf)(gameid);
	}

	DetectedGameList detectGames(const FSList &fslist) const {
		assert(_plugin->_df);
		return (*_plugin->_df)(fslist);
	}
};
#endif

#pragma mark -

#ifdef DYNAMIC_MODULES

class DynamicPlugin : public Plugin {
	void *_dlHandle;
	Common::String _filename;

	Common::String _name;
	GameIDQueryFunc _qf;
	EngineFactory _ef;
	DetectFunc _df;
	GameList _games;

	void *findSymbol(const char *symbol);

public:
	DynamicPlugin(const Common::String &filename)
		: _dlHandle(0), _filename(filename), _qf(0), _ef(0), _df(0), _games() {}

	const char *getName() const					{ return _name.c_str(); }

	PluginError createInstance(OSystem *syst, Engine **engine) const {
		assert(_ef);
		return (*_ef)(syst, engine);
	}

	GameList getSupportedGames() const { return _games; }

	GameDescriptor findGame(const char *gameid) const {
		assert(_qf);
		return (*_qf)(gameid);
	}

	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
#if defined(_WIN32)
	void *func = (void*)GetProcAddress((HMODULE)_dlHandle, symbol);
	if (!func)
		warning("Failed loading symbol '%s' from plugin '%s'", symbol, _filename.c_str());
	return func;
#else
#error TODO
#endif
#endif
}

bool DynamicPlugin::loadPlugin() {
	assert(!_dlHandle);
#if defined(UNIX) || defined(__DC__)
	_dlHandle = dlopen(_filename.c_str(), RTLD_LAZY);

	if (!_dlHandle) {
		warning("Failed loading plugin '%s' (%s)", _filename.c_str(), dlerror());
		return false;
	}
#else
#if defined(_WIN32)
	_dlHandle = LoadLibrary(_filename.c_str());

	if (!_dlHandle) {
		warning("Failed loading plugin '%s'", _filename.c_str());
		return false;
	}
#else
#error TODO
#endif
#endif

	// Query the plugin's name
	NameFunc nameFunc = (NameFunc)findSymbol("PLUGIN_name");
	if (!nameFunc) {
		unloadPlugin();
		return false;
	}
	_name = nameFunc();

	// Query the plugin for the game ids it supports
	GameIDListFunc gameListFunc = (GameIDListFunc)findSymbol("PLUGIN_gameIDList");
	if (!gameListFunc) {
		unloadPlugin();
		return false;
	}
	_games = gameListFunc();

	// Retrieve the gameid query function
	_qf = (GameIDQueryFunc)findSymbol("PLUGIN_findGameID");
	if (!_qf) {
		unloadPlugin();
		return false;
	}

	// 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 defined(UNIX) || defined(__DC__)
		if (dlclose(_dlHandle) != 0)
			warning("Failed unloading plugin '%s' (%s)", _filename.c_str(), dlerror());
#elif defined(_WIN32)
		if (!FreeLibrary((HMODULE)_dlHandle))
			warning("Failed unloading plugin '%s'", _filename.c_str());
#else
#error TODO
#endif
	}
}

#endif	// DYNAMIC_MODULES

#pragma mark -

DECLARE_SINGLETON(PluginManager);

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.

	// Load all plugins.
	// Scan for all plugins in this directory
	FilesystemNode dir(PLUGIN_DIRECTORY);
	FSList files;
	if (!dir.listDir(files, FilesystemNode::kListFilesOnly)) {
		error("Couldn't open plugin directory '%s'", PLUGIN_DIRECTORY);
	}

	for (FSList::const_iterator i = files.begin(); i != files.end(); ++i) {
		Common::String name(i->displayName());
		if (name.hasPrefix(PLUGIN_PREFIX) && name.hasSuffix(PLUGIN_SUFFIX)) {
			tryLoadPlugin(new DynamicPlugin(i->path()));
		}
	}

#else

	#define LINK_PLUGIN(ID) \
		extern PluginRegistrator *g_##ID##_PluginReg; \
		extern void g_##ID##_PluginReg_alloc(); \
		g_##ID##_PluginReg_alloc(); \
		plugin = g_##ID##_PluginReg; \
		tryLoadPlugin(new StaticPlugin(plugin));

	// "Loader" for the static plugins.
	// Iterate over all registered (static) plugins and load them.
	PluginRegistrator *plugin;

	#ifndef DISABLE_SCUMM
	LINK_PLUGIN(SCUMM)
	#endif
	#ifndef DISABLE_SKY
	LINK_PLUGIN(SKY)
	#endif
	#ifndef DISABLE_SWORD1
	LINK_PLUGIN(SWORD1)
	#endif
	#ifndef DISABLE_SWORD2
	LINK_PLUGIN(SWORD2)
	#endif
	#ifndef DISABLE_SIMON
	LINK_PLUGIN(SIMON)
	#endif
	#ifndef DISABLE_QUEEN
	LINK_PLUGIN(QUEEN)
	#endif
	#ifndef DISABLE_SAGA
	LINK_PLUGIN(SAGA)
	#endif
	#ifndef DISABLE_KYRA
	LINK_PLUGIN(KYRA)
	#endif
	#ifndef DISABLE_GOB
	LINK_PLUGIN(GOB)
	#endif
	#ifndef DISABLE_LURE
	LINK_PLUGIN(LURE)
	#endif
	#ifndef DISABLE_CINE
	LINK_PLUGIN(CINE)
	#endif

#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;
}