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  * NOTE: that due to portability issues, behaviour can only be
  65  * guaranteed with @name using ASCII. We canot guarantee that
  66  * an UTF-8 string would work, which is why name is a const char *
  67  * and not a const xmlChar * .
  68  * TODO: options are not yet implemented.
  69  *
  70  * Returns a handle for the module or NULL in case of error
  71  */
  72 xmlModulePtr
  73 xmlModuleOpen(const char *name, int options ATTRIBUTE_UNUSED)
  74 {
  75     xmlModulePtr module;
  76
  77     module = (xmlModulePtr) xmlMalloc(sizeof(xmlModule));
  78     if (module == NULL) {
  79         xmlModuleErrMemory(NULL, "creating module");
  80         return (NULL);
  81     }
  82
  83     memset(module, 0, sizeof(xmlModule));
  84
  85     module->handle = xmlModulePlatformOpen(name);
  86
  87     if (module->handle == NULL) {
  88         xmlFree(module);
  89         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
  90                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
  91                         name, NULL, 0, 0, "failed to open %s\n", name);
  92         return(NULL);
  93     }
  94
  95     module->name = xmlStrdup((const xmlChar *) name);
  96     return (module);
  97 }
  98
  99 /**
 100  * xmlModuleSymbol:
 101  * @module: the module
 102  * @name: the name of the symbol
 103  * @symbol: the resulting symbol address
 104  *
 105  * Lookup for a symbol address in the given module
 106  * NOTE: that due to portability issues, behaviour can only be
 107  * guaranteed with @name using ASCII. We canot guarantee that
 108  * an UTF-8 string would work, which is why name is a const char *
 109  * and not a const xmlChar * .
 110  *
 111  * Returns 0 if the symbol was found, or -1 in case of error
 112  */
 113 int
 114 xmlModuleSymbol(xmlModulePtr module, const char *name, void **symbol)
 115 {
 116     int rc = -1;
 117
 118     if ((NULL == module) || (symbol == NULL) || (name == NULL)) {
 119         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 120                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
 121                         NULL, NULL, 0, 0, "null parameter\n");
 122         return rc;
 123     }
 124
 125     rc = xmlModulePlatformSymbol(module->handle, name, symbol);
 126
 127     if (rc == -1) {
 128         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 129                         XML_MODULE_OPEN, XML_ERR_FATAL, NULL, 0, 0,
 130                         name, NULL, 0, 0,
 131                         "failed to find symbol: %s\n",
 132                         (name == NULL ? "NULL" : name));
 133         return rc;
 134     }
 135
 136     return rc;
 137 }
 138
 139 /**
 140  * xmlModuleClose:
 141  * @module: the module handle
 142  *
 143  * The close operations unload the associated module and free the
 144  * data associated to the module.
 145  *
 146  * Returns 0 in case of success, -1 in case of argument error and -2
 147  *         if the module could not be closed/unloaded.
 148  */
 149 int
 150 xmlModuleClose(xmlModulePtr module)
 151 {
 152     int rc;
 153
 154     if (NULL == module) {
 155         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 156                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, 0,
 157                         NULL, NULL, 0, 0, "null module pointer\n");
 158         return -1;
 159     }
 160
 161     rc = xmlModulePlatformClose(module->handle);
 162
 163     if (rc != 0) {
 164         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 165                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, 0,
 166                         (const char *) module->name, NULL, 0, 0,
 167                         "failed to close: %s\n", module->name);
 168         return -2;
 169     }
 170
 171     rc = xmlModuleFree(module);
 172     return (rc);
 173 }
 174
 175 /**
 176  * xmlModuleFree:
 177  * @module: the module handle
 178  *
 179  * The free operations free the data associated to the module
 180  * but does not unload the associated shared library which may still
 181  * be in use.
 182  *
 183  * Returns 0 in case of success, -1 in case of argument error
 184  */
 185 int
 186 xmlModuleFree(xmlModulePtr module)
 187 {
 188     if (NULL == module) {
 189         __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_MODULE,
 190                         XML_MODULE_CLOSE, XML_ERR_FATAL, NULL, 0, NULL,
 191                         NULL, NULL, 0, 0, "null module pointer\n");
 192         return -1;
 193     }
 194
 195     xmlFree(module->name);
 196     xmlFree(module);
 197
 198     return (0);
 199 }
 200
 201 #if defined(HAVE_DLOPEN) && !defined(_WIN32)
 202 #ifdef HAVE_DLFCN_H
 203 #include <dlfcn.h>
 204 #endif
 205
 206 #ifndef RTLD_GLOBAL            /* For Tru64 UNIX 4.0 */
 207 #define RTLD_GLOBAL 0
 208 #endif
 209
 210 /**
 211  * xmlModulePlatformOpen:
 212  * @name: path to the module
 213  *
 214  * returns a handle on success, and zero on error.
 215  */
 216
 217 static void *
 218 xmlModulePlatformOpen(const char *name)
 219 {
 220     return dlopen(name, RTLD_GLOBAL | RTLD_NOW);
 221 }
 222
 223 /*
 224  * xmlModulePlatformClose:
 225  * @handle: handle to the module
 226  *
 227  * returns 0 on success, and non-zero on error.
 228  */
 229
 230 static int
 231 xmlModulePlatformClose(void *handle)
 232 {
 233     return dlclose(handle);
 234 }
 235
 236 /*
 237  * xmlModulePlatformSymbol:
 238  * http://www.opengroup.org/onlinepubs/009695399/functions/dlsym.html
 239  * returns 0 on success and the loaded symbol in result, and -1 on error.
 240  */
 241
 242 static int
 243 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 244 {
 245     *symbol = dlsym(handle, name);
 246     if (dlerror() != NULL) {
 247         return -1;
 248     }
 249     return 0;
 250 }
 251
 252 #else /* ! HAVE_DLOPEN */
 253
 254 #ifdef HAVE_SHLLOAD             /* HAVE_SHLLOAD */
 255 #ifdef HAVE_DL_H
 256 #include <dl.h>
 257 #endif
 258 /*
 259  * xmlModulePlatformOpen:
 260  * returns a handle on success, and zero on error.
 261  */
 262
 263 static void *
 264 xmlModulePlatformOpen(const char *name)
 265 {
 266     return shl_load(name, BIND_IMMEDIATE, 0L);
 267 }
 268
 269 /*
 270  * xmlModulePlatformClose:
 271  * returns 0 on success, and non-zero on error.
 272  */
 273
 274 static int
 275 xmlModulePlatformClose(void *handle)
 276 {
 277     return shl_unload(handle);
 278 }
 279
 280 /*
 281  * xmlModulePlatformSymbol:
 282  * http://docs.hp.com/en/B2355-90683/shl_load.3X.html
 283  * returns 0 on success and the loaded symbol in result, and -1 on error.
 284  */
 285
 286 static int
 287 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 288 {
 289     int rc;
 290
 291     errno = 0;
 292     rc = shl_findsym(&handle, name, TYPE_UNDEFINED, symbol);
 293     return rc;
 294 }
 295
 296 #endif /* HAVE_SHLLOAD */
 297 #endif /* ! HAVE_DLOPEN */
 298
 299 #ifdef _WIN32
 300
 301 #include <windows.h>
 302
 303 /*
 304  * xmlModulePlatformOpen:
 305  * returns a handle on success, and zero on error.
 306  */
 307
 308 static void *
 309 xmlModulePlatformOpen(const char *name)
 310 {
 311     return LoadLibraryA(name);
 312 }
 313
 314 /*
 315  * xmlModulePlatformClose:
 316  * returns 0 on success, and non-zero on error.
 317  */
 318
 319 static int
 320 xmlModulePlatformClose(void *handle)
 321 {
 322     int rc;
 323
 324     rc = FreeLibrary(handle);
 325     return (0 == rc);
 326 }
 327
 328 /*
 329  * xmlModulePlatformSymbol:
 330  * http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dllproc/base/getprocaddress.asp
 331  * returns 0 on success and the loaded symbol in result, and -1 on error.
 332  */
 333
 334 static int
 335 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 336 {
 337 #ifdef _WIN32_WCE
 338     /*
 339      * GetProcAddressA seems only available on WinCE
 340      */
 341     *symbol = GetProcAddressA(handle, name);
 342 #else
 343     *symbol = GetProcAddress(handle, name);
 344 #endif
 345     return (NULL == *symbol) ? -1 : 0;
 346 }
 347
 348 #endif /* _WIN32 */
 349
 350 #ifdef HAVE_BEOS
 351
 352 #include <kernel/image.h>
 353
 354 /*
 355  * xmlModulePlatformOpen:
 356  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 357  * returns a handle on success, and zero on error.
 358  */
 359
 360 static void *
 361 xmlModulePlatformOpen(const char *name)
 362 {
 363     return (void *) load_add_on(name);
 364 }
 365
 366 /*
 367  * xmlModulePlatformClose:
 368  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 369  * returns 0 on success, and non-zero on error.
 370  */
 371
 372 static int
 373 xmlModulePlatformClose(void *handle)
 374 {
 375     status_t rc;
 376
 377     rc = unload_add_on((image_id) handle);
 378
 379     if (rc == B_OK)
 380         return 0;
 381     else
 382         return -1;
 383 }
 384
 385 /*
 386  * xmlModulePlatformSymbol:
 387  * beos api info: http://www.beunited.org/bebook/The%20Kernel%20Kit/Images.html
 388  * returns 0 on success and the loaded symbol in result, and -1 on error.
 389  */
 390
 391 static int
 392 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 393 {
 394     status_t rc;
 395
 396     rc = get_image_symbol((image_id) handle, name, B_SYMBOL_TYPE_ANY, symbol);
 397
 398     return (rc == B_OK) ? 0 : -1;
 399 }
 400
 401 #endif /* HAVE_BEOS */
 402
 403 #ifdef HAVE_OS2
 404
 405 #include <os2.h>
 406
 407 /*
 408  * xmlModulePlatformOpen:
 409  * os2 api info: http://www.edm2.com/os2api/Dos/DosLoadModule.html
 410  * returns a handle on success, and zero on error.
 411  */
 412
 413 static void *
 414 xmlModulePlatformOpen(const char *name)
 415 {
 416     char errbuf[256];
 417     void *handle;
 418     int rc;
 419
 420     rc = DosLoadModule(errbuf, sizeof(errbuf) - 1, name, &handle);
 421
 422     if (rc)
 423         return 0;
 424     else
 425         return (handle);
 426 }
 427
 428 /*
 429  * xmlModulePlatformClose:
 430  * os2 api info: http://www.edm2.com/os2api/Dos/DosFreeModule.html
 431  * returns 0 on success, and non-zero on error.
 432  */
 433
 434 static int
 435 xmlModulePlatformClose(void *handle)
 436 {
 437     return DosFreeModule(handle);
 438 }
 439
 440 /*
 441  * xmlModulePlatformSymbol:
 442  * os2 api info: http://www.edm2.com/os2api/Dos/DosQueryProcAddr.html
 443  * returns 0 on success and the loaded symbol in result, and -1 on error.
 444  */
 445
 446 static int
 447 xmlModulePlatformSymbol(void *handle, const char *name, void **symbol)
 448 {
 449     int rc;
 450
 451     rc = DosQueryProcAddr(handle, 0, name, symbol);
 452
 453     return (rc == NO_ERROR) ? 0 : -1;
 454 }
 455
 456 #endif /* HAVE_OS2 */
 457
 458 #define bottom_xmlmodule
 459 #include "elfgcchack.h"
 460 #endif /* LIBXML_MODULES_ENABLED */