author | kergoth <kergoth> | 2002-01-25 22:14:26 (UTC) |
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committer | kergoth <kergoth> | 2002-01-25 22:14:26 (UTC) |
commit | 15318cad33835e4e2dc620d033e43cd930676cdd (patch) (unidiff) | |
tree | c2fa0399a2c47fda8e2cd0092c73a809d17f68eb /library/qlibrary.cpp | |
download | opie-15318cad33835e4e2dc620d033e43cd930676cdd.zip opie-15318cad33835e4e2dc620d033e43cd930676cdd.tar.gz opie-15318cad33835e4e2dc620d033e43cd930676cdd.tar.bz2 |
Initial revision
-rw-r--r-- | library/qlibrary.cpp | 437 |
1 files changed, 437 insertions, 0 deletions
diff --git a/library/qlibrary.cpp b/library/qlibrary.cpp new file mode 100644 index 0000000..4aabbc5 --- a/dev/null +++ b/library/qlibrary.cpp | |||
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1 | /********************************************************************** | ||
2 | ** Copyright (C) 2000 Trolltech AS. All rights reserved. | ||
3 | ** | ||
4 | ** This file is part of Qtopia Environment. | ||
5 | ** | ||
6 | ** This file may be distributed and/or modified under the terms of the | ||
7 | ** GNU General Public License version 2 as published by the Free Software | ||
8 | ** Foundation and appearing in the file LICENSE.GPL included in the | ||
9 | ** packaging of this file. | ||
10 | ** | ||
11 | ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE | ||
12 | ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. | ||
13 | ** | ||
14 | ** See http://www.trolltech.com/gpl/ for GPL licensing information. | ||
15 | ** | ||
16 | ** Contact info@trolltech.com if any conditions of this licensing are | ||
17 | ** not clear to you. | ||
18 | ** | ||
19 | **********************************************************************/ | ||
20 | |||
21 | |||
22 | #include "qlibrary_p.h" | ||
23 | |||
24 | // uncomment this to get error messages | ||
25 | //#define QT_DEBUG_COMPONENT 1 | ||
26 | // uncomment this to get error and success messages | ||
27 | //#define QT_DEBUG_COMPONENT 2 | ||
28 | |||
29 | #ifndef QT_DEBUG_COMPONENT | ||
30 | # if defined(QT_DEBUG) | ||
31 | # define QT_DEBUG_COMPONENT 1 | ||
32 | # endif | ||
33 | #endif | ||
34 | |||
35 | #ifndef QT_NO_COMPONENT | ||
36 | |||
37 | // KAI C++ has at the moment problems with unloading the Qt plugins. So don't | ||
38 | // unload them as a workaround for now. | ||
39 | #if defined(Q_CC_KAI) || defined(Q_OS_MAC) | ||
40 | #define QT_NO_LIBRARY_UNLOAD | ||
41 | #endif | ||
42 | |||
43 | #if defined(Q_WS_WIN) && !defined(QT_MAKEDLL) | ||
44 | #define QT_NO_LIBRARY_UNLOAD | ||
45 | #endif | ||
46 | |||
47 | /* Platform independent QLibraryPrivate implementations */ | ||
48 | #ifndef QT_LITE_COMPONENT | ||
49 | |||
50 | #include "qtimer.h" | ||
51 | |||
52 | extern Q_EXPORT QApplication *qApp; | ||
53 | |||
54 | QLibraryPrivate::QLibraryPrivate( QLibrary *lib ) | ||
55 | : QObject( 0, lib->library().latin1() ), pHnd( 0 ), libIface( 0 ), unloadTimer( 0 ), library( lib ) | ||
56 | { | ||
57 | } | ||
58 | |||
59 | QLibraryPrivate::~QLibraryPrivate() | ||
60 | { | ||
61 | if ( libIface ) | ||
62 | libIface->release(); | ||
63 | killTimer(); | ||
64 | } | ||
65 | |||
66 | /* | ||
67 | Only components that implement the QLibraryInterface can | ||
68 | be unloaded automatically. | ||
69 | */ | ||
70 | void QLibraryPrivate::tryUnload() | ||
71 | { | ||
72 | if ( library->policy() == QLibrary::Manual || !pHnd || !libIface ) | ||
73 | return; | ||
74 | |||
75 | if ( !libIface->canUnload() ) | ||
76 | return; | ||
77 | |||
78 | #if defined(QT_DEBUG_COMPONENT) && QT_DEBUG_COMPONENT == 2 | ||
79 | if ( library->unload() ) | ||
80 | qDebug( "%s has been automatically unloaded", library->library().latin1() ); | ||
81 | #else | ||
82 | library->unload(); | ||
83 | #endif | ||
84 | } | ||
85 | |||
86 | #else // QT_LITE_COMPOINENT | ||
87 | |||
88 | QLibraryPrivate::QLibraryPrivate( QLibrary *lib ) | ||
89 | : pHnd( 0 ), libIface( 0 ), library( lib ) | ||
90 | { | ||
91 | } | ||
92 | |||
93 | #endif // QT_LITE_COMPOINENT | ||
94 | |||
95 | void QLibraryPrivate::startTimer() | ||
96 | { | ||
97 | #ifndef QT_LITE_COMPONENT | ||
98 | unloadTimer = new QTimer( this ); | ||
99 | connect( unloadTimer, SIGNAL( timeout() ), this, SLOT( tryUnload() ) ); | ||
100 | unloadTimer->start( 5000, FALSE ); | ||
101 | #endif | ||
102 | } | ||
103 | |||
104 | void QLibraryPrivate::killTimer() | ||
105 | { | ||
106 | #ifndef QT_LITE_COMPONENT | ||
107 | delete unloadTimer; | ||
108 | unloadTimer = 0; | ||
109 | #endif | ||
110 | } | ||
111 | |||
112 | /*! | ||
113 | \class QLibrary qlibrary.h | ||
114 | |||
115 | \brief The QLibrary class provides a wrapper for handling shared libraries. | ||
116 | |||
117 | This class is temporarily copied from Qt 3.0. | ||
118 | */ | ||
119 | |||
120 | /*! | ||
121 | \enum QLibrary::Policy | ||
122 | |||
123 | This enum type defines the various policies a QLibrary can have with respect to | ||
124 | loading and unloading the shared library. | ||
125 | |||
126 | The \e policy can be: | ||
127 | |||
128 | \value Delayed The library get's loaded as soon as needed and unloaded in the destructor | ||
129 | \value Immediately The library is loaded immediately and unloaded in the destructor | ||
130 | \value Manual Like delayed, and library has to be unloaded manually | ||
131 | */ | ||
132 | |||
133 | /*! | ||
134 | Creates a QLibrary object for the shared library \a filename. | ||
135 | The library get's loaded if \a pol is Immediately. | ||
136 | |||
137 | Note that \a filename does not need to include the (platform specific) | ||
138 | file extension, so calling | ||
139 | |||
140 | \code | ||
141 | QLibrary lib( "mylib" ); | ||
142 | \endcode | ||
143 | |||
144 | would be equivalent to | ||
145 | |||
146 | \code | ||
147 | QLibrary lib( "mylib.dll" ); | ||
148 | \endcode | ||
149 | |||
150 | on Windows. But \e "mylib.dll" will obviously not work on other platforms. | ||
151 | |||
152 | \sa setPolicy(), unload() | ||
153 | */ | ||
154 | QLibrary::QLibrary( const QString& filename, Policy pol ) | ||
155 | : libfile( filename ), libPol( pol ), entry( 0 ) | ||
156 | { | ||
157 | d = new QLibraryPrivate( this ); | ||
158 | if ( pol == Immediately ) | ||
159 | load(); | ||
160 | } | ||
161 | |||
162 | /*! | ||
163 | Deletes the QLibrary object. | ||
164 | The library will be unloaded if the policy is not Manual. | ||
165 | |||
166 | \sa unload(), setPolicy() | ||
167 | */ | ||
168 | QLibrary::~QLibrary() | ||
169 | { | ||
170 | if ( libPol == Manual || !unload() ) { | ||
171 | if ( entry ) { | ||
172 | entry->release(); | ||
173 | entry = 0; | ||
174 | } | ||
175 | } | ||
176 | delete d; | ||
177 | } | ||
178 | |||
179 | void QLibrary::createInstanceInternal() | ||
180 | { | ||
181 | if ( libfile.isEmpty() ) | ||
182 | return; | ||
183 | |||
184 | if ( !d->pHnd ) { | ||
185 | ASSERT( entry == 0 ); | ||
186 | load(); | ||
187 | } | ||
188 | |||
189 | if ( d->pHnd && !entry ) { | ||
190 | #if defined(QT_DEBUG_COMPONENT) && QT_DEBUG_COMPONENT == 2 | ||
191 | qWarning( "%s has been loaded.", library().latin1() ); | ||
192 | #endif | ||
193 | typedef QUnknownInterface* (*UCMInstanceProc)(); | ||
194 | UCMInstanceProc ucmInstanceProc; | ||
195 | ucmInstanceProc = (UCMInstanceProc) resolve( "ucm_instantiate" ); | ||
196 | entry = ucmInstanceProc ? ucmInstanceProc() : 0; | ||
197 | if ( entry ) { | ||
198 | entry->queryInterface( IID_QLibrary, (QUnknownInterface**)&d->libIface); | ||
199 | if ( d->libIface ) { | ||
200 | if ( !d->libIface->init() ) { | ||
201 | #if defined(QT_DEBUG_COMPONENT) | ||
202 | qWarning( "%s: QLibraryInterface::init() failed.", library().latin1() ); | ||
203 | #endif | ||
204 | unload(); | ||
205 | return; | ||
206 | } | ||
207 | |||
208 | d->killTimer(); | ||
209 | if ( libPol != Manual ) | ||
210 | d->startTimer(); | ||
211 | } | ||
212 | } else { | ||
213 | #if defined(QT_DEBUG_COMPONENT) | ||
214 | qWarning( "%s: No interface implemented.", library().latin1() ); | ||
215 | #endif | ||
216 | unload(); | ||
217 | } | ||
218 | } | ||
219 | } | ||
220 | |||
221 | /*! | ||
222 | Returns the address of the exported symbol \a symb. The library gets | ||
223 | loaded if necessary. The function returns NULL if the symbol could | ||
224 | not be resolved, or if loading the library failed. | ||
225 | |||
226 | \code | ||
227 | typedef int (*addProc)( int, int ); | ||
228 | |||
229 | addProc add = (addProc) library->resolve( "add" ); | ||
230 | if ( add ) | ||
231 | return add( 5, 8 ); | ||
232 | else | ||
233 | return 5 + 8; | ||
234 | \endcode | ||
235 | |||
236 | \sa queryInterface() | ||
237 | */ | ||
238 | void *QLibrary::resolve( const char* symb ) | ||
239 | { | ||
240 | if ( !d->pHnd ) | ||
241 | load(); | ||
242 | if ( !d->pHnd ) | ||
243 | return 0; | ||
244 | |||
245 | void *address = d->resolveSymbol( symb ); | ||
246 | if ( !address ) { | ||
247 | #if defined(QT_DEBUG_COMPONENT) | ||
248 | // resolveSymbol() might give a warning; so let that warning look so fatal | ||
249 | qWarning( QString("Trying to resolve symbol \"_%1\" instead").arg( symb ) ); | ||
250 | #endif | ||
251 | address = d->resolveSymbol( QString( "_" ) + symb ); | ||
252 | } | ||
253 | return address; | ||
254 | } | ||
255 | |||
256 | /*! | ||
257 | \overload | ||
258 | |||
259 | Loads the library \a filename and returns the address of the exported symbol \a symb. | ||
260 | Note that like for the constructor, \a filename does not need to include the (platform specific) | ||
261 | file extension. The library staying loaded until the process exits. | ||
262 | |||
263 | The function returns a null pointer if the symbol could not be resolved or if loading | ||
264 | the library failed. | ||
265 | */ | ||
266 | void *QLibrary::resolve( const QString &filename, const char *symb ) | ||
267 | { | ||
268 | QLibrary lib( filename, Manual ); | ||
269 | return lib.resolve( symb ); | ||
270 | } | ||
271 | |||
272 | /*! | ||
273 | Returns whether the library is loaded. | ||
274 | |||
275 | \sa unload() | ||
276 | */ | ||
277 | bool QLibrary::isLoaded() const | ||
278 | { | ||
279 | return d->pHnd != 0; | ||
280 | } | ||
281 | |||
282 | /*! | ||
283 | Loads the library. | ||
284 | */ | ||
285 | bool QLibrary::load() | ||
286 | { | ||
287 | return d->loadLibrary(); | ||
288 | } | ||
289 | |||
290 | /*! | ||
291 | Releases the component and unloads the library when successful. | ||
292 | Returns TRUE if the library could be unloaded, otherwise FALSE. | ||
293 | If the component implements the QLibraryInterface, the cleanup() | ||
294 | function of this interface will be called. The unloading will be | ||
295 | cancelled if the subsequent call to canUnload() returns FALSE. | ||
296 | |||
297 | This function gets called automatically in the destructor if | ||
298 | the policy is not Manual. | ||
299 | |||
300 | \warning | ||
301 | If \a force is set to TRUE, the library gets unloaded at any cost, | ||
302 | which is in most cases a segmentation fault, so you should know what | ||
303 | you're doing! | ||
304 | |||
305 | \sa queryInterface(), resolve() | ||
306 | */ | ||
307 | bool QLibrary::unload( bool force ) | ||
308 | { | ||
309 | if ( !d->pHnd ) | ||
310 | return TRUE; | ||
311 | |||
312 | if ( entry ) { | ||
313 | if ( d->libIface ) { | ||
314 | d->libIface->cleanup(); | ||
315 | |||
316 | bool can = d->libIface->canUnload(); | ||
317 | can = ( d->libIface->release() <= 1 ) && can; | ||
318 | // the "entry" member must be the last reference to the component | ||
319 | if ( can || force ) { | ||
320 | d->libIface = 0; | ||
321 | } else { | ||
322 | #if defined(QT_DEBUG_COMPONENT) | ||
323 | qWarning( "%s prevents unloading!", library().latin1() ); | ||
324 | #endif | ||
325 | d->libIface->addRef(); | ||
326 | return FALSE; | ||
327 | } | ||
328 | } | ||
329 | |||
330 | if ( entry->release() ) { | ||
331 | #if defined(QT_DEBUG_COMPONENT) | ||
332 | qWarning( "%s is still in use!", library().latin1() ); | ||
333 | #endif | ||
334 | if ( force ) { | ||
335 | delete entry; | ||
336 | } else { | ||
337 | entry->addRef(); | ||
338 | return FALSE; | ||
339 | } | ||
340 | } | ||
341 | d->killTimer(); | ||
342 | |||
343 | entry = 0; | ||
344 | } | ||
345 | |||
346 | // ### this is a hack to solve problems with plugin unloading und KAI C++ | ||
347 | // (other compilers may have the same problem) | ||
348 | #if !defined(QT_NO_LIBRARY_UNLOAD) | ||
349 | if ( !d->freeLibrary() ) { | ||
350 | #if defined(QT_DEBUG_COMPONENT) | ||
351 | qWarning( "%s could not be unloaded.", library().latin1() ); | ||
352 | #endif | ||
353 | return FALSE; | ||
354 | #else | ||
355 | return TRUE; | ||
356 | #endif | ||
357 | #if !defined(QT_NO_LIBRARY_UNLOAD) | ||
358 | } | ||
359 | |||
360 | #if defined(QT_DEBUG_COMPONENT) && QT_DEBUG_COMPONENT == 2 | ||
361 | qWarning( "%s has been unloaded.", library().latin1() ); | ||
362 | #endif | ||
363 | |||
364 | d->pHnd = 0; | ||
365 | return TRUE; | ||
366 | #endif | ||
367 | } | ||
368 | |||
369 | /*! | ||
370 | Sets the current policy to \a pol. | ||
371 | The library is loaded if \a pol is set to Immediately. | ||
372 | */ | ||
373 | void QLibrary::setPolicy( Policy pol ) | ||
374 | { | ||
375 | libPol = pol; | ||
376 | |||
377 | if ( libPol == Immediately && !d->pHnd ) | ||
378 | load(); | ||
379 | } | ||
380 | |||
381 | /*! | ||
382 | Returns the current policy. | ||
383 | |||
384 | \sa setPolicy() | ||
385 | */ | ||
386 | QLibrary::Policy QLibrary::policy() const | ||
387 | { | ||
388 | return libPol; | ||
389 | } | ||
390 | |||
391 | /*! | ||
392 | Returns the filename of the shared library this QLibrary object handles, | ||
393 | including the platform specific file extension. | ||
394 | |||
395 | \code | ||
396 | QLibrary lib( "mylib" ); | ||
397 | QString str = lib.library(); | ||
398 | \endcode | ||
399 | |||
400 | will set \e str to "mylib.dll" on Windows, and "libmylib.so" on Linux. | ||
401 | */ | ||
402 | QString QLibrary::library() const | ||
403 | { | ||
404 | if ( libfile.isEmpty() ) | ||
405 | return libfile; | ||
406 | |||
407 | QString filename = libfile; | ||
408 | #if defined(Q_WS_WIN) | ||
409 | if ( filename.find( ".dll" ) == -1 ) | ||
410 | filename += ".dll"; | ||
411 | #elif defined(Q_OS_MACX) | ||
412 | if ( filename.find( ".dylib" ) == -1 ) | ||
413 | filename += ".dylib"; | ||
414 | #else | ||
415 | if ( filename.find( ".so" ) == -1 ) | ||
416 | filename = QString( "lib%1.so" ).arg( filename ); | ||
417 | #endif | ||
418 | |||
419 | return filename; | ||
420 | } | ||
421 | |||
422 | /*! | ||
423 | Forwards the query to the component and returns the result. \a request and \a iface | ||
424 | are propagated to the component's queryInterface implementation. | ||
425 | |||
426 | The library gets loaded if necessary. | ||
427 | */ | ||
428 | QRESULT QLibrary::queryInterface( const QUuid& request, QUnknownInterface** iface ) | ||
429 | { | ||
430 | if ( !entry ) { | ||
431 | createInstanceInternal(); | ||
432 | } | ||
433 | |||
434 | return entry ? entry->queryInterface( request, iface ) : QE_NOINTERFACE; | ||
435 | } | ||
436 | |||
437 | #endif // QT_NO_COMPONENT | ||