third_party/libxml/src/xmlmodule.c

   1 /*
   2  * xmlmodule.c : basic API for dynamic module loading added 2.6.17
   3  *
   4  * See Copyright for the status of this software.
   5  *
   6  * joelwreed@comcast.net
   7  *
   8  * http://www.fortran-2000.com/ArnaudRecipes/sharedlib.html
   9  */
  10
  11 #define IN_LIBXML
  12 #include "libxml.h"
  13
  14 #include <string.h>
  15 #include <libxml/xmlmemory.h>
  16 #include <libxml/xmlerror.h>
  17 #include <libxml/xmlmodule.h>
  18 #include <libxml/globals.h>
  19
  20 #ifdef LIBXML_MODULES_ENABLED
  21
  22 struct _xmlModule {
  23     unsigned char *name;
  24     void *handle;
  25 };
  26
  27 static void *xmlModulePlatformOpen(const char *name);
  28 static int xmlModulePlatformClose(void *handle);
  29 static int xmlModulePlatformSymbol(void *handle, const char *name, void **result);
  30
  31 /************************************************************************
  32  *                                                                      *
  33  *              module memory error handler                             *
  34  *                                                                      *
  35  ************************************************************************/
  36
  37 /**
  38  * xmlModuleErrMemory:
  39  * @extra:  extra information
  40  *
  41  * Handle an out of memory condition
  42  */
  43 static void
  44 xmlModuleErrMemory(xmlModulePtr module, const char *extra)
  45 {
  46     const char *name = NULL;
  47
  48     if (module != NULL) {
  49         name = (const char *) module->name;
  50     }
  51
  52     __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
  53                     XML_ERR_NO_MEMORY, XML_ERR_FATAL, NULL, 0, extra,
  54                     name, NULL, 0, 0,
  55                     "Memory allocation failed : %s\n", extra);
  56 }
  57
  58 /**
  59  * xmlModuleOpen:
  60  * @name: the module name
  61  * @options: a set of xmlModuleOption
  62  *
  63  * Opens a module/shared library given its name or path
  64  * TODO: options are not yet implemented.
  65  *
  66  * Returns a handle for the module or NULL in case of error
  67  */
  68 xmlModulePtr
  69 xmlModuleOpen(const char *name, int options ATTRIBUTE_UNUSED)
  70 {
  71     xmlModulePtr module;
  72
  73     module = (xmlModulePtr) xmlMalloc(sizeof(xmlModule));
  74     if (module == NULL) {
  75         xmlModuleErrMemory(NULL, "creating module");
  76         return (NULL);
  77     }
  78
  79     memset(module, 0, sizeof(xmlModule));
  80
  81     module->handle = xmlModulePlatformOpen(name);
  82
  83     if (module->handle == NULL) {
  84         xmlFree(module);
  85         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
  86                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
  87                         name, NULL, 0, 0, "failed to open %s\n", name);
  88         return(NULL);
  89     }
  90
  91     module->name = xmlStrdup((const xmlChar *) name);
  92     return (module);
  93 }
  94
  95 /**
  96  * xmlModuleSymbol:
  97  * @module: the module
  98  * @name: the name of the symbol
  99  * @symbol: the resulting symbol address
 100  *
 101  * Lookup for a symbol address in the given module
 102  *
 103  * Returns 0 if the symbol was found, or -1 in case of error
 104  */
 105 int
 106 xmlModuleSymbol(xmlModulePtr module, const char *name, void **symbol)
 107 {
 108     int rc = -1;
 109
 110     if ((NULL == module) || (symbol == NULL)) {
 111         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 112                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
 113                         NULL, NULL, 0, 0, "null parameter\n");
 114         return rc;
 115     }
 116
 117     rc = xmlModulePlatformSymbol(module->handle, name, symbol);
 118
 119     if (rc == -1) {
 120         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 121                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
 122                         name, NULL, 0, 0,
 123                         "failed to find symbol: %s\n",
 124                         (name == NULL ? "NULL" : name));
 125         return rc;
 126     }
 127
 128     return rc;
 129 }
 130
 131 /**
 132  * xmlModuleClose:
 133  * @module: the module handle
 134  *
 135  * The close operations unload the associated module and free the
 136  * data associated to the module.
 137  *
 138  * Returns 0 in case of success, -1 in case of argument error and -2
 139  *         if the module could not be closed/unloaded.
 140  */
 141 int
 142 xmlModuleClose(xmlModulePtr module)
 143 {
 144     int rc;
 145
 146     if (NULL == module) {
 147         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 148                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, 0,
 149                         NULL, NULL, 0, 0, "null module pointer\n");
 150         return -1;
 151     }
 152
 153     rc = xmlModulePlatformClose(module->handle);
 154
 155     if (rc != 0) {
 156         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 157                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, 0,
 158                         (const char *) module->name, NULL, 0, 0,
 159                         "failed to close: %s\n", module->name);
 160         return -2;
 161     }
 162
 163     rc = xmlModuleFree(module);
 164     return (rc);
 165 }
 166
 167 /**
 168  * xmlModuleFree:
 169  * @module: the module handle
 170  *
 171  * The free operations free the data associated to the module
 172  * but does not unload the associated shared library which may still
 173  * be in use.
 174  *
 175  * Returns 0 in case of success, -1 in case of argument error
 176  */
 177 int
 178 xmlModuleFree(xmlModulePtr module)
 179 {
 180     if (NULL == module) {
 181         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 182                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, NULL,
 183                         NULL, NULL, 0, 0, "null module pointer\n");
 184         return -1;
 185     }
 186
 187     xmlFree(module->name);
 188     xmlFree(module);
 189
 190     return (0);
 191 }
 192
 193 #if defined(HAVE_DLOPEN) && !defined(_WIN32)
 194 #ifdef HAVE_DLFCN_H
 195 #include <dlfcn.h>
 196 #endif
 197
 198 #ifndef RTLD_GLOBAL            /* For Tru64 UNIX 4.0 */
 199 #define RTLD_GLOBAL 0
 200 #endif
 201
 202 /**
 203  * xmlModulePlatformOpen:
 204  * @name: path to the module
 205  *
 206  * returns a handle on success, and zero on error.
 207  */
 208
 209 static void *
 210 xmlModulePlatformOpen(const char *name)
 211 {
 212     return dlopen(name, RTLD_GLOBAL | RTLD_NOW);
 213 }
 214
 215 /*
 216  * xmlModulePlatformClose:
 217  * @handle: handle to the module
 218  *
 219  * returns 0 on success, and non-zero on error.
 220  */
 221
 222 static int
 223 xmlModulePlatformClose(void *handle)
 224 {
 225     return dlclose(handle);
 226 }
 227
 228 /*
 229  * xmlModulePlatformSymbol:
 230  * http://www.opengroup.org/onlinepubs/009695399/functions/dlsym.html
 231  * returns 0 on success and the loaded symbol in result, and -1 on error.
 232  */
 233
 234 static int
 235 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 236 {
 237     *symbol = dlsym(handle, name);
 238     if (dlerror() != NULL) {
 239         return -1;
 240     }
 241     return 0;
 242 }
 243
 244 #else /* ! HAVE_DLOPEN */
 245
 246 #ifdef HAVE_SHLLOAD             /* HAVE_SHLLOAD */
 247 #ifdef HAVE_DL_H
 248 #include <dl.h>
 249 #endif
 250 /*
 251  * xmlModulePlatformOpen:
 252  * returns a handle on success, and zero on error.
 253  */
 254
 255 static void *
 256 xmlModulePlatformOpen(const char *name)
 257 {
 258     return shl_load(name, BIND_IMMEDIATE, 0L);
 259 }
 260
 261 /*
 262  * xmlModulePlatformClose:
 263  * returns 0 on success, and non-zero on error.
 264  */
 265
 266 static int
 267 xmlModulePlatformClose(void *handle)
 268 {
 269     return shl_unload(handle);
 270 }
 271
 272 /*
 273  * xmlModulePlatformSymbol:
 274  * http://docs.hp.com/en/B2355-90683/shl_load.3X.html
 275  * returns 0 on success and the loaded symbol in result, and -1 on error.
 276  */
 277
 278 static int
 279 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 280 {
 281     int rc;
 282
 283     errno = 0;
 284     rc = shl_findsym(&handle, name, TYPE_UNDEFINED, symbol);
 285     return rc;
 286 }
 287
 288 #endif /* HAVE_SHLLOAD */
 289 #endif /* ! HAVE_DLOPEN */
 290
 291 #ifdef _WIN32
 292
 293 #include <windows.h>
 294
 295 /*
 296  * xmlModulePlatformOpen:
 297  * returns a handle on success, and zero on error.
 298  */
 299
 300 static void *
 301 xmlModulePlatformOpen(const char *name)
 302 {
 303     return LoadLibraryA(name);
 304 }
 305
 306 /*
 307  * xmlModulePlatformClose:
 308  * returns 0 on success, and non-zero on error.
 309  */
 310
 311 static int
 312 xmlModulePlatformClose(void *handle)
 313 {
 314     int rc;
 315
 316     rc = FreeLibrary(handle);
 317     return (0 == rc);
 318 }
 319
 320 /*
 321  * xmlModulePlatformSymbol:
 322  * http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/getprocaddress.asp
 323  * returns 0 on success and the loaded symbol in result, and -1 on error.
 324  */
 325
 326 static int
 327 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 328 {
 329     *symbol = GetProcAddress(handle, name);
 330     return (NULL == *symbol) ? -1 : 0;
 331 }
 332
 333 #endif /* _WIN32 */
 334
 335 #ifdef HAVE_BEOS
 336
 337 #include <kernel/image.h>
 338
 339 /*
 340  * xmlModulePlatformOpen:
 341  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 342  * returns a handle on success, and zero on error.
 343  */
 344
 345 static void *
 346 xmlModulePlatformOpen(const char *name)
 347 {
 348     return (void *) load_add_on(name);
 349 }
 350
 351 /*
 352  * xmlModulePlatformClose:
 353  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 354  * returns 0 on success, and non-zero on error.
 355  */
 356
 357 static int
 358 xmlModulePlatformClose(void *handle)
 359 {
 360     status_t rc;
 361
 362     rc = unload_add_on((image_id) handle);
 363
 364     if (rc == B_OK)
 365         return 0;
 366     else
 367         return -1;
 368 }
 369
 370 /*
 371  * xmlModulePlatformSymbol:
 372  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 373  * returns 0 on success and the loaded symbol in result, and -1 on error.
 374  */
 375
 376 static int
 377 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 378 {
 379     status_t rc;
 380
 381     rc = get_image_symbol((image_id) handle, name, B_SYMBOL_TYPE_ANY, symbol);
 382
 383     return (rc == B_OK) ? 0 : -1;
 384 }
 385
 386 #endif /* HAVE_BEOS */
 387
 388 #ifdef HAVE_OS2
 389
 390 #include <os2.h>
 391
 392 /*
 393  * xmlModulePlatformOpen:
 394  * os2 api info: http://www.edm2.com/os2api/Dos/DosLoadModule.html
 395  * returns a handle on success, and zero on error.
 396  */
 397
 398 static void *
 399 xmlModulePlatformOpen(const char *name)
 400 {
 401     char errbuf[256];
 402     void *handle;
 403     int rc;
 404
 405     rc = DosLoadModule(errbuf, sizeof(errbuf) - 1, name, &handle);
 406
 407     if (rc)
 408         return 0;
 409     else
 410         return (handle);
 411 }
 412
 413 /*
 414  * xmlModulePlatformClose:
 415  * os2 api info: http://www.edm2.com/os2api/Dos/DosFreeModule.html
 416  * returns 0 on success, and non-zero on error.
 417  */
 418
 419 static int
 420 xmlModulePlatformClose(void *handle)
 421 {
 422     return DosFreeModule(handle);
 423 }
 424
 425 /*
 426  * xmlModulePlatformSymbol:
 427  * os2 api info: http://www.edm2.com/os2api/Dos/DosQueryProcAddr.html
 428  * returns 0 on success and the loaded symbol in result, and -1 on error.
 429  */
 430
 431 static int
 432 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 433 {
 434     int rc;
 435
 436     rc = DosQueryProcAddr(handle, 0, name, symbol);
 437
 438     return (rc == NO_ERROR) ? 0 : -1;
 439 }
 440
 441 #endif /* HAVE_OS2 */
 442
 443 #define bottom_xmlmodule
 444 #include "elfgcchack.h"
 445 #endif /* LIBXML_MODULES_ENABLED */