src/ptlib/unix/udll.cxx

   1 /*
   2  * udll.cxx
   3  *
   4  * Dynamic Link Library implementation.
   5  *
   6  * Portable Windows Library
   7  *
   8  * Copyright (c) 1993-1998 Equivalence Pty. Ltd.
   9  *
  10  * The contents of this file are subject to the Mozilla Public License
  11  * Version 1.0 (the "License"); you may not use this file except in
  12  * compliance with the License. You may obtain a copy of the License at
  13  * http://www.mozilla.org/MPL/
  14  *
  15  * Software distributed under the License is distributed on an "AS IS"
  16  * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  17  * the License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * The Original Code is Portable Windows Library.
  21  *
  22  * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
  23  *
  24  * Portions are Copyright (C) 1993 Free Software Foundation, Inc.
  25  * All Rights Reserved.
  26  *
  27  * Contributor(s): ______________________________________.
  28  *
  29  * $Log$
  30  * Revision 1.24  2007/07/06 02:12:14  csoutheren
  31  * Add extra memory leak debugging on Linux
  32  * Remove compile warnings
  33  *
  34  * Revision 1.23  2006/08/20 00:32:00  csoutheren
  35  * Fixed error reporting on DLL load error
  36  *
  37  * Revision 1.22  2006/07/18 05:15:58  csoutheren
  38  * Removed pre-emptive call to dlerror as this crashes RedHat 9
  39  *
  40  * Revision 1.21  2006/06/20 13:26:19  csoutheren
  41  * Only call dlerror if error occurs
  42  *
  43  * Revision 1.20  2006/06/20 05:36:38  csoutheren
  44  * Patch 1471705 rewritten to make threadsafe
  45  * Display error from dlopen if available
  46  * Thanks to Joerg Pulz
  47  *
  48  * Revision 1.19  2005/11/30 12:47:42  csoutheren
  49  * Removed tabs, reformatted some code, and changed tags for Doxygen
  50  *
  51  * Revision 1.18  2005/08/04 20:10:24  csoutheren
  52  * Apply patch #1217596
  53  * Fixed problems with MacOSX Tiger
  54  * Thanks to Hannes Friederich
  55  *
  56  * Revision 1.17  2004/05/11 01:15:53  csoutheren
  57  * Included name into Unix PDynaLink implementation
  58  *
  59  * Revision 1.16  2003/09/11 00:52:13  dereksmithies
  60  * Full dependancy check on dynamically loading a library.
  61  * Thanks to Snark on #gnomemeeting for pointing this out...
  62  *
  63  * Revision 1.15  2003/07/09 11:37:13  rjongbloed
  64  * Fixed corrct closing of DLL (setting handle to NULL) thanks Fabrizio Ammollo
  65  *
  66  * Revision 1.14  2003/05/14 10:50:30  dereksmithies
  67  * Quick hack to add the function: PDynaLink::GetName().  Fix me.
  68  *
  69  * Revision 1.13  2003/05/06 06:59:12  robertj
  70  * Dynamic library support for MacOSX, thanks Hugo Santos
  71  *
  72  * Revision 1.12  2003/04/16 07:17:35  craigs
  73  * CHanged to use new #define
  74  *
  75  * Revision 1.11  2001/06/30 06:59:07  yurik
  76  * Jac Goudsmit from Be submit these changes 6/28. Implemented by Yuri Kiryanov
  77  *
  78  * Revision 1.10  2001/03/07 06:57:52  yurik
  79  * Changed email to current one
  80  *
  81  * Revision 1.9  2000/03/10 08:21:17  rogerh
  82  * Add correct OpenBSD support
  83  *
  84  * Revision 1.8  2000/03/09 18:41:53  rogerh
  85  * Workaround for OpenBSD. This breaks the functionality on OpenBSD but
  86  * gains us a clean compilation. We can return to this problem later.
  87  *
  88  * Revision 1.7  1999/02/22 13:26:54  robertj
  89  * BeOS port changes.
  90  *
  91  * Revision 1.6  1999/02/06 05:49:44  robertj
  92  * BeOS port effort by Yuri Kiryanov <openh323@kiryanov.com>
  93  *
  94  * Revision 1.5  1998/11/30 21:52:03  robertj
  95  * New directory structure.
  96  *
  97  * Revision 1.4  1998/09/24 04:12:26  robertj
  98  * Added open software license.
  99  *
 100  * Revision 1.3  1998/01/04 08:11:41  craigs
 101  * Remove Solarisism and made platform independent
 102  *
 103  * Revision 1.2  1997/10/30 12:41:22  craigs
 104  * Added GetExtension command
 105  *
 106  * Revision 1.1  1997/04/22 10:58:17  craigs
 107  * Initial revision
 108  *
 109  *
 110  */
 111
 112 #pragma implementation "dynalink.h"
 113
 114 #include <ptlib.h>
 115
 116 #ifdef P_MACOSX
 117 #if P_MACOSX < 700
 118
 119 /*
 120 Copyright (c) 2002 Peter O'Gorman <ogorman@users.sourceforge.net>
 121
 122 Permission is hereby granted, free of charge, to any person obtaining
 123 a copy of this software and associated documentation files (the
 124 "Software"), to deal in the Software without restriction, including
 125 without limitation the rights to use, copy, modify, merge, publish,
 126 distribute, sublicense, and/or sell copies of the Software, and to
 127 permit persons to whom the Software is furnished to do so, subject to
 128 the following conditions:
 129
 130 The above copyright notice and this permission notice shall be
 131 included in all copies or substantial portions of the Software.
 132
 133 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 134 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 135 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 136 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 137 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 138 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 139 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 140 */
 141
 142
 143 /* Just to prove that it isn't that hard to add Mac calls to your code :)
 144    This works with pretty much everything, including kde3 xemacs and the gimp,
 145    I'd guess that it'd work in at least 95% of cases, use this as your starting
 146    point, rather than the mess that is dlfcn.c, assuming that your code does not
 147    require ref counting or symbol lookups in dependent libraries
 148 */
 149
 150 #include <stdio.h>
 151 #include <stdlib.h>
 152 #include <string.h>
 153 #include <sys/types.h>
 154 #include <sys/stat.h>
 155 #include <stdarg.h>
 156 #include <limits.h>
 157 #include <mach-o/dyld.h>
 158
 159 #define RTLD_LAZY       0x1
 160 #define RTLD_NOW        0x2
 161 #define RTLD_LOCAL      0x4
 162 #define RTLD_GLOBAL     0x8
 163 #define RTLD_NOLOAD     0x10
 164 #define RTLD_NODELETE   0x80
 165
 166 #define ERR_STR_LEN 256
 167
 168 static void *dlsymIntern(void *handle, const char *symbol);
 169
 170 static const char *error(int setget, const char *str, ...);
 171
 172 /* Set and get the error string for use by dlerror */
 173 static const char *error(int setget, const char *str, ...)
 174 {
 175   static char errstr[ERR_STR_LEN];
 176   static int err_filled = 0;
 177   const char *retval;
 178   va_list arg;
 179   if (setget == 0)
 180   {
 181     va_start(arg, str);
 182     strncpy(errstr, "dlsimple: ", ERR_STR_LEN);
 183     vsnprintf(errstr + 10, ERR_STR_LEN - 10, str, arg);
 184     va_end(arg);
 185     err_filled = 1;
 186     retval = NULL;
 187   }
 188   else
 189   {
 190     if (!err_filled)
 191       retval = NULL;
 192     else
 193       retval = errstr;
 194     err_filled = 0;
 195   }
 196   return retval;
 197 }
 198
 199 /* dlopen */
 200 static void *dlopen(const char *path, int mode)
 201 {
 202   void *module = 0;
 203   NSObjectFileImage ofi = 0;
 204   NSObjectFileImageReturnCode ofirc;
 205   static int (*make_private_module_public) (NSModule module) = 0;
 206   unsigned int flags =  NSLINKMODULE_OPTION_RETURN_ON_ERROR | NSLINKMODULE_OPTION_PRIVATE;
 207
 208   /* If we got no path, the app wants the global namespace, use -1 as the marker
 209      in this case */
 210   if (!path)
 211     return (void *)-1;
 212
 213   /* Create the object file image, works for things linked with the -bundle arg to ld */
 214   ofirc = NSCreateObjectFileImageFromFile(path, &ofi);
 215   switch (ofirc)
 216   {
 217     case NSObjectFileImageSuccess:
 218       /* It was okay, so use NSLinkModule to link in the image */
 219       if (!(mode & RTLD_LAZY)) flags += NSLINKMODULE_OPTION_BINDNOW;
 220       module = NSLinkModule(ofi, path,flags);
 221       /* Don't forget to destroy the object file image, unless you like leaks */
 222       NSDestroyObjectFileImage(ofi);
 223       /* If the mode was global, then change the module, this avoids
 224          multiply defined symbol errors to first load private then make
 225          global. Silly, isn't it. */
 226       if ((mode & RTLD_GLOBAL))
 227       {
 228         if (!make_private_module_public)
 229         {
 230           _dyld_func_lookup("__dyld_NSMakePrivateModulePublic",
 231         (unsigned long *)&make_private_module_public);
 232         }
 233         make_private_module_public(module);
 234       }
 235       break;
 236     case NSObjectFileImageInappropriateFile:
 237       /* It may have been a dynamic library rather than a bundle, try to load it */
 238       module = (void *)NSAddImage(path, NSADDIMAGE_OPTION_RETURN_ON_ERROR);
 239       break;
 240     case NSObjectFileImageFailure:
 241       error(0,"Object file setup failure :  \"%s\"", path);
 242       return 0;
 243     case NSObjectFileImageArch:
 244       error(0,"No object for this architecture :  \"%s\"", path);
 245       return 0;
 246     case NSObjectFileImageFormat:
 247       error(0,"Bad object file format :  \"%s\"", path);
 248       return 0;
 249     case NSObjectFileImageAccess:
 250       error(0,"Can't read object file :  \"%s\"", path);
 251       return 0;
 252   }
 253   if (!module)
 254     error(0, "Can not open \"%s\"", path);
 255   return module;
 256 }
 257
 258 /* dlsymIntern is used by dlsym to find the symbol */
 259 static void *dlsymIntern(void *handle, const char *symbol)
 260 {
 261   NSSymbol *nssym = 0;
 262   /* If the handle is -1, if is the app global context */
 263   if (handle == (void *)-1)
 264   {
 265     /* Global context, use NSLookupAndBindSymbol */
 266     if (NSIsSymbolNameDefined(symbol))
 267     {
 268       nssym = NSLookupAndBindSymbol(symbol);
 269     }
 270
 271   }
 272   /* Now see if the handle is a struch mach_header* or not, use NSLookupSymbol in image
 273      for libraries, and NSLookupSymbolInModule for bundles */
 274   else
 275   {
 276     /* Check for both possible magic numbers depending on x86/ppc byte order */
 277     if ((((struct mach_header *)handle)->magic == MH_MAGIC) ||
 278       (((struct mach_header *)handle)->magic == MH_CIGAM))
 279     {
 280       if (NSIsSymbolNameDefinedInImage((struct mach_header *)handle, symbol))
 281       {
 282         nssym = NSLookupSymbolInImage((struct mach_header *)handle,
 283                         symbol,
 284                         NSLOOKUPSYMBOLINIMAGE_OPTION_BIND
 285                         | NSLOOKUPSYMBOLINIMAGE_OPTION_RETURN_ON_ERROR);
 286       }
 287
 288     }
 289     else
 290     {
 291       nssym = NSLookupSymbolInModule(handle, symbol);
 292     }
 293   }
 294   if (!nssym)
 295   {
 296     error(0, "Symbol \"%s\" Not found", symbol);
 297     return NULL;
 298   }
 299   return NSAddressOfSymbol(nssym);
 300 }
 301
 302 static const char *dlerror(void)
 303 {
 304   return error(1, (char *)NULL);
 305 }
 306
 307 static int dlclose(void *handle)
 308 {
 309   if ((((struct mach_header *)handle)->magic == MH_MAGIC) ||
 310     (((struct mach_header *)handle)->magic == MH_CIGAM))
 311   {
 312     error(0, "Can't remove dynamic libraries on darwin");
 313     return 0;
 314   }
 315   if (!NSUnLinkModule(handle, 0))
 316   {
 317     error(0, "unable to unlink module %s", NSNameOfModule(handle));
 318     return 1;
 319   }
 320   return 0;
 321 }
 322
 323
 324 /* dlsym, prepend the underscore and call dlsymIntern */
 325 static void *dlsym(void *handle, const char *symbol)
 326 {
 327   static char undersym[257];  /* Saves calls to malloc(3) */
 328   int sym_len = strlen(symbol);
 329   void *value = NULL;
 330   char *malloc_sym = NULL;
 331
 332   if (sym_len < 256)
 333   {
 334     snprintf(undersym, 256, "_%s", symbol);
 335     value = dlsymIntern(handle, undersym);
 336   }
 337   else
 338   {
 339     malloc_sym = malloc(sym_len + 2);
 340     if (malloc_sym)
 341     {
 342       sprintf(malloc_sym, "_%s", symbol);
 343       value = dlsymIntern(handle, malloc_sym);
 344       free(malloc_sym);
 345     }
 346     else
 347     {
 348       error(0, "Unable to allocate memory");
 349     }
 350   }
 351   return value;
 352 }
 353
 354 #else
 355
 356 // The functionality implemented above ships directly with MacOSX 10.3 and later
 357 #include <dlfcn.h>
 358
 359 #endif // P_MACOSX < 700
 360
 361 #endif // P_MACOSX
 362
 363 static PMutex & GetDLLMutex()
 364 {
 365   static PMutex mutex;
 366   return mutex;
 367 }
 368
 369 #ifndef  P_DYNALINK
 370
 371 #warning "No implementation for dynamic library functions"
 372
 373 #else
 374
 375 PDynaLink::PDynaLink()
 376 {
 377   dllHandle = NULL;
 378 }
 379
 380 PDynaLink::PDynaLink(const PString & _name)
 381   : name(_name)
 382 {
 383   dllHandle = NULL;
 384   Open(_name);
 385 }
 386
 387 PDynaLink::~PDynaLink()
 388 {
 389   Close();
 390 }
 391
 392 PString PDynaLink::GetExtension()
 393 {
 394   return PString(".so");
 395 }
 396
 397 BOOL PDynaLink::Open(const PString & _name)
 398 {
 399   Close();
 400
 401   name = _name;
 402
 403   {
 404     PWaitAndSignal m(GetDLLMutex());
 405
 406     const char *err; //= dlerror();
 407
 408 #if defined(P_OPENBSD)
 409     dllHandle = dlopen((char *)(const char *)name, RTLD_NOW);
 410 #else
 411     dllHandle = dlopen((const char *)name, RTLD_NOW);
 412 #endif
 413
 414     if (dllHandle == NULL) {
 415       err = dlerror();
 416       PTRACE_IF(1, err != NULL, "DLL\tError loading DLL - " << err);
 417     }
 418   }
 419
 420   return IsLoaded();
 421 }
 422
 423 void PDynaLink::Close()
 424 {
 425   if (dllHandle != NULL) {
 426     dlclose(dllHandle);
 427     dllHandle = NULL;
 428   }
 429   name.MakeEmpty();
 430 }
 431
 432 BOOL PDynaLink::IsLoaded() const
 433 {
 434   return dllHandle != NULL;
 435 }
 436
 437 PString PDynaLink::GetName(BOOL full) const
 438 {
 439   if (!IsLoaded())
 440     return "";
 441
 442   PString str = name;
 443   PINDEX pos = str.FindLast('/');
 444   if (pos != P_MAX_INDEX)
 445     str = str.Mid(pos+1);
 446   pos = str.FindLast(".so");
 447   if (pos != P_MAX_INDEX)
 448     str = str.Left(pos);
 449
 450   return str;
 451 }
 452
 453
 454 BOOL PDynaLink::GetFunction(PINDEX, Function &)
 455 {
 456   return FALSE;
 457 }
 458
 459 BOOL PDynaLink::GetFunction(const PString & fn, Function & func)
 460 {
 461   if (dllHandle == NULL)
 462     return FALSE;
 463
 464 #if defined(P_OPENBSD)
 465   void * p = dlsym(dllHandle, (char *)(const char *)fn);
 466 #else
 467   void * p = dlsym(dllHandle, (const char *)fn);
 468 #endif
 469
 470   if (p == NULL)
 471     return FALSE;
 472
 473   func = (Function)p;
 474   return TRUE;
 475 }
 476
 477 #endif
 478
 479 // End of file
 480