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