threads.c

   1 /**
   2  * threads.c: set of generic threading related routines
   3  *
   4  * See Copyright for the status of this software.
   5  *
   6  * Gary Pennington <Gary.Pennington@uk.sun.com>
   7  * daniel@veillard.com
   8  */
   9
  10 #define IN_LIBXML
  11 #include "libxml.h"
  12
  13 #include <string.h>
  14
  15 #include <libxml/threads.h>
  16 #include <libxml/globals.h>
  17
  18 #ifdef HAVE_SYS_TYPES_H
  19 #include <sys/types.h>
  20 #endif
  21 #ifdef HAVE_UNISTD_H
  22 #include <unistd.h>
  23 #endif
  24 #ifdef HAVE_STDLIB_H
  25 #include <stdlib.h>
  26 #endif
  27 #ifdef HAVE_PTHREAD_H
  28 #include <pthread.h>
  29 #elif defined HAVE_WIN32_THREADS
  30 #include <windows.h>
  31 #ifndef HAVE_COMPILER_TLS
  32 #include <process.h>
  33 #endif
  34 #endif
  35
  36 #ifdef HAVE_BEOS_THREADS
  37 #include <OS.h>
  38 #include <TLS.h>
  39 #endif
  40
  41 #if defined(SOLARIS)
  42 #include <note.h>
  43 #endif
  44
  45 /* #define DEBUG_THREADS */
  46
  47 #ifdef HAVE_PTHREAD_H
  48
  49 static int libxml_is_threaded = -1;
  50 #if defined(__GNUC__) && defined(__GLIBC__)
  51 #ifdef __linux__
  52 #if (__GNUC__ == 3 && __GNUC_MINOR__ >= 3) || (__GNUC__ > 3)
  53 #pragma weak pthread_once
  54 #pragma weak pthread_getspecific
  55 #pragma weak pthread_setspecific
  56 #pragma weak pthread_key_create
  57 #pragma weak pthread_key_delete
  58 #pragma weak pthread_mutex_init
  59 #pragma weak pthread_mutex_destroy
  60 #pragma weak pthread_mutex_lock
  61 #pragma weak pthread_mutex_unlock
  62 #pragma weak pthread_cond_init
  63 #pragma weak pthread_cond_destroy
  64 #pragma weak pthread_cond_wait
  65 #pragma weak pthread_equal
  66 #pragma weak pthread_self
  67 #pragma weak pthread_key_create
  68 #pragma weak pthread_key_delete
  69 #pragma weak pthread_cond_signal
  70 #endif
  71 #endif /* __linux__ */
  72 #endif /* defined(__GNUC__) && defined(__GLIBC__) */
  73 #endif /* HAVE_PTHREAD_H */
  74
  75 /*
  76  * TODO: this module still uses malloc/free and not xmlMalloc/xmlFree
  77  *       to avoid some crazyness since xmlMalloc/xmlFree may actually
  78  *       be hosted on allocated blocks needing them for the allocation ...
  79  */
  80
  81 /*
  82  * xmlMutex are a simple mutual exception locks
  83  */
  84 struct _xmlMutex {
  85 #ifdef HAVE_PTHREAD_H
  86     pthread_mutex_t lock;
  87 #elif defined HAVE_WIN32_THREADS
  88     HANDLE mutex;
  89 #elif defined HAVE_BEOS_THREADS
  90     sem_id sem;
  91     thread_id tid;
  92 #else
  93     int empty;
  94 #endif
  95 };
  96
  97 /*
  98  * xmlRMutex are reentrant mutual exception locks
  99  */
 100 struct _xmlRMutex {
 101 #ifdef HAVE_PTHREAD_H
 102     pthread_mutex_t lock;
 103     unsigned int held;
 104     unsigned int waiters;
 105     pthread_t tid;
 106     pthread_cond_t cv;
 107 #elif defined HAVE_WIN32_THREADS
 108     CRITICAL_SECTION cs;
 109     unsigned int count;
 110 #elif defined HAVE_BEOS_THREADS
 111     xmlMutexPtr lock;
 112     thread_id tid;
 113     int32 count;
 114 #else
 115     int empty;
 116 #endif
 117 };
 118
 119 /*
 120  * This module still has some internal static data.
 121  *   - xmlLibraryLock a global lock
 122  *   - globalkey used for per-thread data
 123  */
 124
 125 #ifdef HAVE_PTHREAD_H
 126 static pthread_key_t globalkey;
 127 static pthread_t mainthread;
 128 static pthread_once_t once_control = PTHREAD_ONCE_INIT;
 129 static pthread_once_t once_control_init = PTHREAD_ONCE_INIT;
 130 static pthread_mutex_t global_init_lock = PTHREAD_MUTEX_INITIALIZER;
 131 #elif defined HAVE_WIN32_THREADS
 132 #if defined(HAVE_COMPILER_TLS)
 133 static __declspec(thread) xmlGlobalState tlstate;
 134 static __declspec(thread) int tlstate_inited = 0;
 135 #else /* HAVE_COMPILER_TLS */
 136 static DWORD globalkey = TLS_OUT_OF_INDEXES;
 137 #endif /* HAVE_COMPILER_TLS */
 138 static DWORD mainthread;
 139 static struct {
 140     DWORD done;
 141     DWORD control;
 142 } run_once = { 0, 0};
 143 static volatile LPCRITICAL_SECTION global_init_lock = NULL;
 144
 145 /* endif HAVE_WIN32_THREADS */
 146 #elif defined HAVE_BEOS_THREADS
 147 int32 globalkey = 0;
 148 thread_id mainthread = 0;
 149 int32 run_once_init = 0;
 150 static int32 global_init_lock = -1;
 151 static vint32 global_init_count = 0;
 152 #endif
 153
 154 static xmlRMutexPtr xmlLibraryLock = NULL;
 155
 156 #ifdef LIBXML_THREAD_ENABLED
 157 static void xmlOnceInit(void);
 158 #endif
 159
 160 /**
 161  * xmlNewMutex:
 162  *
 163  * xmlNewMutex() is used to allocate a libxml2 token struct for use in
 164  * synchronizing access to data.
 165  *
 166  * Returns a new simple mutex pointer or NULL in case of error
 167  */
 168 xmlMutexPtr
 169 xmlNewMutex(void)
 170 {
 171     xmlMutexPtr tok;
 172
 173     if ((tok = malloc(sizeof(xmlMutex))) == NULL)
 174         return (NULL);
 175 #ifdef HAVE_PTHREAD_H
 176     if (libxml_is_threaded != 0)
 177         pthread_mutex_init(&tok->lock, NULL);
 178 #elif defined HAVE_WIN32_THREADS
 179     tok->mutex = CreateMutex(NULL, FALSE, NULL);
 180 #elif defined HAVE_BEOS_THREADS
 181     if ((tok->sem = create_sem(1, "xmlMutex")) < B_OK) {
 182         free(tok);
 183         return NULL;
 184     }
 185     tok->tid = -1;
 186 #endif
 187     return (tok);
 188 }
 189
 190 /**
 191  * xmlFreeMutex:
 192  * @tok:  the simple mutex
 193  *
 194  * xmlFreeMutex() is used to reclaim resources associated with a libxml2 token
 195  * struct.
 196  */
 197 void
 198 xmlFreeMutex(xmlMutexPtr tok)
 199 {
 200     if (tok == NULL)
 201         return;
 202
 203 #ifdef HAVE_PTHREAD_H
 204     if (libxml_is_threaded != 0)
 205         pthread_mutex_destroy(&tok->lock);
 206 #elif defined HAVE_WIN32_THREADS
 207     CloseHandle(tok->mutex);
 208 #elif defined HAVE_BEOS_THREADS
 209     delete_sem(tok->sem);
 210 #endif
 211     free(tok);
 212 }
 213
 214 /**
 215  * xmlMutexLock:
 216  * @tok:  the simple mutex
 217  *
 218  * xmlMutexLock() is used to lock a libxml2 token.
 219  */
 220 void
 221 xmlMutexLock(xmlMutexPtr tok)
 222 {
 223     if (tok == NULL)
 224         return;
 225 #ifdef HAVE_PTHREAD_H
 226     if (libxml_is_threaded != 0)
 227         pthread_mutex_lock(&tok->lock);
 228 #elif defined HAVE_WIN32_THREADS
 229     WaitForSingleObject(tok->mutex, INFINITE);
 230 #elif defined HAVE_BEOS_THREADS
 231     if (acquire_sem(tok->sem) != B_NO_ERROR) {
 232 #ifdef DEBUG_THREADS
 233         xmlGenericError(xmlGenericErrorContext,
 234                         "xmlMutexLock():BeOS:Couldn't aquire semaphore\n");
 235 #endif
 236     }
 237     tok->tid = find_thread(NULL);
 238 #endif
 239
 240 }
 241
 242 /**
 243  * xmlMutexUnlock:
 244  * @tok:  the simple mutex
 245  *
 246  * xmlMutexUnlock() is used to unlock a libxml2 token.
 247  */
 248 void
 249 xmlMutexUnlock(xmlMutexPtr tok)
 250 {
 251     if (tok == NULL)
 252         return;
 253 #ifdef HAVE_PTHREAD_H
 254     if (libxml_is_threaded != 0)
 255         pthread_mutex_unlock(&tok->lock);
 256 #elif defined HAVE_WIN32_THREADS
 257     ReleaseMutex(tok->mutex);
 258 #elif defined HAVE_BEOS_THREADS
 259     if (tok->tid == find_thread(NULL)) {
 260         tok->tid = -1;
 261         release_sem(tok->sem);
 262     }
 263 #endif
 264 }
 265
 266 /**
 267  * xmlNewRMutex:
 268  *
 269  * xmlRNewMutex() is used to allocate a reentrant mutex for use in
 270  * synchronizing access to data. token_r is a re-entrant lock and thus useful
 271  * for synchronizing access to data structures that may be manipulated in a
 272  * recursive fashion.
 273  *
 274  * Returns the new reentrant mutex pointer or NULL in case of error
 275  */
 276 xmlRMutexPtr
 277 xmlNewRMutex(void)
 278 {
 279     xmlRMutexPtr tok;
 280
 281     if ((tok = malloc(sizeof(xmlRMutex))) == NULL)
 282         return (NULL);
 283 #ifdef HAVE_PTHREAD_H
 284     if (libxml_is_threaded != 0) {
 285         pthread_mutex_init(&tok->lock, NULL);
 286         tok->held = 0;
 287         tok->waiters = 0;
 288         pthread_cond_init(&tok->cv, NULL);
 289     }
 290 #elif defined HAVE_WIN32_THREADS
 291     InitializeCriticalSection(&tok->cs);
 292     tok->count = 0;
 293 #elif defined HAVE_BEOS_THREADS
 294     if ((tok->lock = xmlNewMutex()) == NULL) {
 295         free(tok);
 296         return NULL;
 297     }
 298     tok->count = 0;
 299 #endif
 300     return (tok);
 301 }
 302
 303 /**
 304  * xmlFreeRMutex:
 305  * @tok:  the reentrant mutex
 306  *
 307  * xmlRFreeMutex() is used to reclaim resources associated with a
 308  * reentrant mutex.
 309  */
 310 void
 311 xmlFreeRMutex(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
 312 {
 313     if (tok == NULL)
 314         return;
 315 #ifdef HAVE_PTHREAD_H
 316     if (libxml_is_threaded != 0) {
 317         pthread_mutex_destroy(&tok->lock);
 318         pthread_cond_destroy(&tok->cv);
 319     }
 320 #elif defined HAVE_WIN32_THREADS
 321     DeleteCriticalSection(&tok->cs);
 322 #elif defined HAVE_BEOS_THREADS
 323     xmlFreeMutex(tok->lock);
 324 #endif
 325     free(tok);
 326 }
 327
 328 /**
 329  * xmlRMutexLock:
 330  * @tok:  the reentrant mutex
 331  *
 332  * xmlRMutexLock() is used to lock a libxml2 token_r.
 333  */
 334 void
 335 xmlRMutexLock(xmlRMutexPtr tok)
 336 {
 337     if (tok == NULL)
 338         return;
 339 #ifdef HAVE_PTHREAD_H
 340     if (libxml_is_threaded == 0)
 341         return;
 342
 343     pthread_mutex_lock(&tok->lock);
 344     if (tok->held) {
 345         if (pthread_equal(tok->tid, pthread_self())) {
 346             tok->held++;
 347             pthread_mutex_unlock(&tok->lock);
 348             return;
 349         } else {
 350             tok->waiters++;
 351             while (tok->held)
 352                 pthread_cond_wait(&tok->cv, &tok->lock);
 353             tok->waiters--;
 354         }
 355     }
 356     tok->tid = pthread_self();
 357     tok->held = 1;
 358     pthread_mutex_unlock(&tok->lock);
 359 #elif defined HAVE_WIN32_THREADS
 360     EnterCriticalSection(&tok->cs);
 361     tok->count++;
 362 #elif defined HAVE_BEOS_THREADS
 363     if (tok->lock->tid == find_thread(NULL)) {
 364         tok->count++;
 365         return;
 366     } else {
 367         xmlMutexLock(tok->lock);
 368         tok->count = 1;
 369     }
 370 #endif
 371 }
 372
 373 /**
 374  * xmlRMutexUnlock:
 375  * @tok:  the reentrant mutex
 376  *
 377  * xmlRMutexUnlock() is used to unlock a libxml2 token_r.
 378  */
 379 void
 380 xmlRMutexUnlock(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
 381 {
 382     if (tok == NULL)
 383         return;
 384 #ifdef HAVE_PTHREAD_H
 385     if (libxml_is_threaded == 0)
 386         return;
 387
 388     pthread_mutex_lock(&tok->lock);
 389     tok->held--;
 390     if (tok->held == 0) {
 391         if (tok->waiters)
 392             pthread_cond_signal(&tok->cv);
 393         memset(&tok->tid, 0, sizeof(tok->tid));
 394     }
 395     pthread_mutex_unlock(&tok->lock);
 396 #elif defined HAVE_WIN32_THREADS
 397     if (tok->count > 0) {
 398         tok->count--;
 399         LeaveCriticalSection(&tok->cs);
 400     }
 401 #elif defined HAVE_BEOS_THREADS
 402     if (tok->lock->tid == find_thread(NULL)) {
 403         tok->count--;
 404         if (tok->count == 0) {
 405             xmlMutexUnlock(tok->lock);
 406         }
 407         return;
 408     }
 409 #endif
 410 }
 411
 412 /**
 413  * xmlGlobalInitMutexLock
 414  *
 415  * Makes sure that the global initialization mutex is initialized and
 416  * locks it.
 417  */
 418 void
 419 __xmlGlobalInitMutexLock(void)
 420 {
 421     /* Make sure the global init lock is initialized and then lock it. */
 422 #ifdef HAVE_PTHREAD_H
 423     /* The mutex is statically initialized, so we just lock it. */
 424     if (pthread_mutex_lock != NULL)
 425         pthread_mutex_lock(&global_init_lock);
 426 #elif defined HAVE_WIN32_THREADS
 427     LPCRITICAL_SECTION cs;
 428
 429     /* Create a new critical section */
 430     if (global_init_lock == NULL) {
 431         cs = malloc(sizeof(CRITICAL_SECTION));
 432         if (cs == NULL) {
 433             xmlGenericError(xmlGenericErrorContext,
 434                             "xmlGlobalInitMutexLock: out of memory\n");
 435             return;
 436         }
 437         InitializeCriticalSection(cs);
 438
 439         /* Swap it into the global_init_lock */
 440 #ifdef InterlockedCompareExchangePointer
 441         InterlockedCompareExchangePointer(&global_init_lock, cs, NULL);
 442 #else /* Use older void* version */
 443         InterlockedCompareExchange((void **) &global_init_lock,
 444                                    (void *) cs, NULL);
 445 #endif /* InterlockedCompareExchangePointer */
 446
 447         /* If another thread successfully recorded its critical
 448          * section in the global_init_lock then discard the one
 449          * allocated by this thread. */
 450         if (global_init_lock != cs) {
 451             DeleteCriticalSection(cs);
 452             free(cs);
 453         }
 454     }
 455
 456     /* Lock the chosen critical section */
 457     EnterCriticalSection(global_init_lock);
 458 #elif defined HAVE_BEOS_THREADS
 459     int32 sem;
 460
 461     /* Allocate a new semaphore */
 462     sem = create_sem(1, "xmlGlobalinitMutex");
 463
 464     while (global_init_lock == -1) {
 465         if (atomic_add(&global_init_count, 1) == 0) {
 466             global_init_lock = sem;
 467         } else {
 468             snooze(1);
 469             atomic_add(&global_init_count, -1);
 470         }
 471     }
 472
 473     /* If another thread successfully recorded its critical
 474      * section in the global_init_lock then discard the one
 475      * allocated by this thread. */
 476     if (global_init_lock != sem)
 477         delete_sem(sem);
 478
 479     /* Acquire the chosen semaphore */
 480     if (acquire_sem(global_init_lock) != B_NO_ERROR) {
 481 #ifdef DEBUG_THREADS
 482         xmlGenericError(xmlGenericErrorContext,
 483                         "xmlGlobalInitMutexLock():BeOS:Couldn't acquire semaphore\n");
 484 #endif
 485     }
 486 #endif
 487 }
 488
 489 void
 490 __xmlGlobalInitMutexUnlock(void)
 491 {
 492 #ifdef HAVE_PTHREAD_H
 493     if (pthread_mutex_unlock != NULL)
 494         pthread_mutex_unlock(&global_init_lock);
 495 #elif defined HAVE_WIN32_THREADS
 496     if (global_init_lock != NULL) {
 497         LeaveCriticalSection(global_init_lock);
 498     }
 499 #elif defined HAVE_BEOS_THREADS
 500     release_sem(global_init_lock);
 501 #endif
 502 }
 503
 504 /**
 505  * xmlGlobalInitMutexDestroy
 506  *
 507  * Makes sure that the global initialization mutex is destroyed before
 508  * application termination.
 509  */
 510 void
 511 __xmlGlobalInitMutexDestroy(void)
 512 {
 513 #ifdef HAVE_PTHREAD_H
 514 #elif defined HAVE_WIN32_THREADS
 515     if (global_init_lock != NULL) {
 516         DeleteCriticalSection(global_init_lock);
 517         free(global_init_lock);
 518         global_init_lock = NULL;
 519     }
 520 #endif
 521 }
 522
 523 /************************************************************************
 524  *                                                                      *
 525  *                      Per thread global state handling                *
 526  *                                                                      *
 527  ************************************************************************/
 528
 529 #ifdef LIBXML_THREAD_ENABLED
 530 #ifdef xmlLastError
 531 #undef xmlLastError
 532 #endif
 533
 534 /**
 535  * xmlFreeGlobalState:
 536  * @state:  a thread global state
 537  *
 538  * xmlFreeGlobalState() is called when a thread terminates with a non-NULL
 539  * global state. It is is used here to reclaim memory resources.
 540  */
 541 static void
 542 xmlFreeGlobalState(void *state)
 543 {
 544     xmlGlobalState *gs = (xmlGlobalState *) state;
 545
 546     /* free any memory allocated in the thread's xmlLastError */
 547     xmlResetError(&(gs->xmlLastError));
 548     free(state);
 549 }
 550
 551 /**
 552  * xmlNewGlobalState:
 553  *
 554  * xmlNewGlobalState() allocates a global state. This structure is used to
 555  * hold all data for use by a thread when supporting backwards compatibility
 556  * of libxml2 to pre-thread-safe behaviour.
 557  *
 558  * Returns the newly allocated xmlGlobalStatePtr or NULL in case of error
 559  */
 560 static xmlGlobalStatePtr
 561 xmlNewGlobalState(void)
 562 {
 563     xmlGlobalState *gs;
 564
 565     gs = malloc(sizeof(xmlGlobalState));
 566     if (gs == NULL) {
 567         xmlGenericError(xmlGenericErrorContext,
 568                         "xmlGetGlobalState: out of memory\n");
 569         return (NULL);
 570     }
 571
 572     memset(gs, 0, sizeof(xmlGlobalState));
 573     xmlInitializeGlobalState(gs);
 574     return (gs);
 575 }
 576 #endif /* LIBXML_THREAD_ENABLED */
 577
 578 #ifdef HAVE_PTHREAD_H
 579 #elif defined HAVE_WIN32_THREADS
 580 #if !defined(HAVE_COMPILER_TLS)
 581 #if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
 582 typedef struct _xmlGlobalStateCleanupHelperParams {
 583     HANDLE thread;
 584     void *memory;
 585 } xmlGlobalStateCleanupHelperParams;
 586
 587 static void XMLCDECL
 588 xmlGlobalStateCleanupHelper(void *p)
 589 {
 590     xmlGlobalStateCleanupHelperParams *params =
 591         (xmlGlobalStateCleanupHelperParams *) p;
 592     WaitForSingleObject(params->thread, INFINITE);
 593     CloseHandle(params->thread);
 594     xmlFreeGlobalState(params->memory);
 595     free(params);
 596     _endthread();
 597 }
 598 #else /* LIBXML_STATIC && !LIBXML_STATIC_FOR_DLL */
 599
 600 typedef struct _xmlGlobalStateCleanupHelperParams {
 601     void *memory;
 602     struct _xmlGlobalStateCleanupHelperParams *prev;
 603     struct _xmlGlobalStateCleanupHelperParams *next;
 604 } xmlGlobalStateCleanupHelperParams;
 605
 606 static xmlGlobalStateCleanupHelperParams *cleanup_helpers_head = NULL;
 607 static CRITICAL_SECTION cleanup_helpers_cs;
 608
 609 #endif /* LIBXMLSTATIC && !LIBXML_STATIC_FOR_DLL */
 610 #endif /* HAVE_COMPILER_TLS */
 611 #endif /* HAVE_WIN32_THREADS */
 612
 613 #if defined HAVE_BEOS_THREADS
 614
 615 /**
 616  * xmlGlobalStateCleanup:
 617  * @data: unused parameter
 618  *
 619  * Used for Beos only
 620  */
 621 void
 622 xmlGlobalStateCleanup(void *data)
 623 {
 624     void *globalval = tls_get(globalkey);
 625
 626     if (globalval != NULL)
 627         xmlFreeGlobalState(globalval);
 628 }
 629 #endif
 630
 631 /**
 632  * xmlGetGlobalState:
 633  *
 634  * xmlGetGlobalState() is called to retrieve the global state for a thread.
 635  *
 636  * Returns the thread global state or NULL in case of error
 637  */
 638 xmlGlobalStatePtr
 639 xmlGetGlobalState(void)
 640 {
 641 #ifdef HAVE_PTHREAD_H
 642     xmlGlobalState *globalval;
 643
 644     if (libxml_is_threaded == 0)
 645         return (NULL);
 646
 647     pthread_once(&once_control, xmlOnceInit);
 648
 649     if ((globalval = (xmlGlobalState *)
 650          pthread_getspecific(globalkey)) == NULL) {
 651         xmlGlobalState *tsd = xmlNewGlobalState();
 652         if (tsd == NULL)
 653             return(NULL);
 654
 655         pthread_setspecific(globalkey, tsd);
 656         return (tsd);
 657     }
 658     return (globalval);
 659 #elif defined HAVE_WIN32_THREADS
 660 #if defined(HAVE_COMPILER_TLS)
 661     if (!tlstate_inited) {
 662         tlstate_inited = 1;
 663         xmlInitializeGlobalState(&tlstate);
 664     }
 665     return &tlstate;
 666 #else /* HAVE_COMPILER_TLS */
 667     xmlGlobalState *globalval;
 668     xmlGlobalStateCleanupHelperParams *p;
 669
 670     xmlOnceInit();
 671 #if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
 672     globalval = (xmlGlobalState *) TlsGetValue(globalkey);
 673 #else
 674     p = (xmlGlobalStateCleanupHelperParams *) TlsGetValue(globalkey);
 675     globalval = (xmlGlobalState *) (p ? p->memory : NULL);
 676 #endif
 677     if (globalval == NULL) {
 678         xmlGlobalState *tsd = xmlNewGlobalState();
 679
 680         if (tsd == NULL)
 681             return(NULL);
 682         p = (xmlGlobalStateCleanupHelperParams *)
 683             malloc(sizeof(xmlGlobalStateCleanupHelperParams));
 684         if (p == NULL) {
 685             xmlGenericError(xmlGenericErrorContext,
 686                             "xmlGetGlobalState: out of memory\n");
 687             xmlFreeGlobalState(tsd);
 688             return(NULL);
 689         }
 690         p->memory = tsd;
 691 #if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
 692         DuplicateHandle(GetCurrentProcess(), GetCurrentThread(),
 693                         GetCurrentProcess(), &p->thread, 0, TRUE,
 694                         DUPLICATE_SAME_ACCESS);
 695         TlsSetValue(globalkey, tsd);
 696         _beginthread(xmlGlobalStateCleanupHelper, 0, p);
 697 #else
 698         EnterCriticalSection(&cleanup_helpers_cs);
 699         if (cleanup_helpers_head != NULL) {
 700             cleanup_helpers_head->prev = p;
 701         }
 702         p->next = cleanup_helpers_head;
 703         p->prev = NULL;
 704         cleanup_helpers_head = p;
 705         TlsSetValue(globalkey, p);
 706         LeaveCriticalSection(&cleanup_helpers_cs);
 707 #endif
 708
 709         return (tsd);
 710     }
 711     return (globalval);
 712 #endif /* HAVE_COMPILER_TLS */
 713 #elif defined HAVE_BEOS_THREADS
 714     xmlGlobalState *globalval;
 715
 716     xmlOnceInit();
 717
 718     if ((globalval = (xmlGlobalState *) tls_get(globalkey)) == NULL) {
 719         xmlGlobalState *tsd = xmlNewGlobalState();
 720         if (tsd == NULL)
 721             return (NULL);
 722
 723         tls_set(globalkey, tsd);
 724         on_exit_thread(xmlGlobalStateCleanup, NULL);
 725         return (tsd);
 726     }
 727     return (globalval);
 728 #else
 729     return (NULL);
 730 #endif
 731 }
 732
 733 /************************************************************************
 734  *                                                                      *
 735  *                      Library wide thread interfaces                  *
 736  *                                                                      *
 737  ************************************************************************/
 738
 739 /**
 740  * xmlGetThreadId:
 741  *
 742  * xmlGetThreadId() find the current thread ID number
 743  * Note that this is likely to be broken on some platforms using pthreads
 744  * as the specification doesn't mandate pthread_t to be an integer type
 745  *
 746  * Returns the current thread ID number
 747  */
 748 int
 749 xmlGetThreadId(void)
 750 {
 751 #ifdef HAVE_PTHREAD_H
 752     pthread_t id;
 753     int ret;
 754
 755     if (libxml_is_threaded == 0)
 756         return (0);
 757     id = pthread_self();
 758     /* horrible but preserves compat, see warning above */
 759     memcpy(&ret, &id, sizeof(ret));
 760     return (ret);
 761 #elif defined HAVE_WIN32_THREADS
 762     return GetCurrentThreadId();
 763 #elif defined HAVE_BEOS_THREADS
 764     return find_thread(NULL);
 765 #else
 766     return ((int) 0);
 767 #endif
 768 }
 769
 770 /**
 771  * xmlIsMainThread:
 772  *
 773  * xmlIsMainThread() check whether the current thread is the main thread.
 774  *
 775  * Returns 1 if the current thread is the main thread, 0 otherwise
 776  */
 777 int
 778 xmlIsMainThread(void)
 779 {
 780 #ifdef HAVE_PTHREAD_H
 781     if (libxml_is_threaded == -1)
 782         xmlInitThreads();
 783     if (libxml_is_threaded == 0)
 784         return (1);
 785     pthread_once(&once_control, xmlOnceInit);
 786 #elif defined HAVE_WIN32_THREADS
 787     xmlOnceInit();
 788 #elif defined HAVE_BEOS_THREADS
 789     xmlOnceInit();
 790 #endif
 791
 792 #ifdef DEBUG_THREADS
 793     xmlGenericError(xmlGenericErrorContext, "xmlIsMainThread()\n");
 794 #endif
 795 #ifdef HAVE_PTHREAD_H
 796     return (pthread_equal(mainthread,pthread_self()));
 797 #elif defined HAVE_WIN32_THREADS
 798     return (mainthread == GetCurrentThreadId());
 799 #elif defined HAVE_BEOS_THREADS
 800     return (mainthread == find_thread(NULL));
 801 #else
 802     return (1);
 803 #endif
 804 }
 805
 806 /**
 807  * xmlLockLibrary:
 808  *
 809  * xmlLockLibrary() is used to take out a re-entrant lock on the libxml2
 810  * library.
 811  */
 812 void
 813 xmlLockLibrary(void)
 814 {
 815 #ifdef DEBUG_THREADS
 816     xmlGenericError(xmlGenericErrorContext, "xmlLockLibrary()\n");
 817 #endif
 818     xmlRMutexLock(xmlLibraryLock);
 819 }
 820
 821 /**
 822  * xmlUnlockLibrary:
 823  *
 824  * xmlUnlockLibrary() is used to release a re-entrant lock on the libxml2
 825  * library.
 826  */
 827 void
 828 xmlUnlockLibrary(void)
 829 {
 830 #ifdef DEBUG_THREADS
 831     xmlGenericError(xmlGenericErrorContext, "xmlUnlockLibrary()\n");
 832 #endif
 833     xmlRMutexUnlock(xmlLibraryLock);
 834 }
 835
 836 /**
 837  * xmlInitThreads:
 838  *
 839  * xmlInitThreads() is used to to initialize all the thread related
 840  * data of the libxml2 library.
 841  */
 842 void
 843 xmlInitThreads(void)
 844 {
 845 #ifdef HAVE_PTHREAD_H
 846     if (libxml_is_threaded == -1) {
 847         if ((pthread_once != NULL) &&
 848             (pthread_getspecific != NULL) &&
 849             (pthread_setspecific != NULL) &&
 850             (pthread_key_create != NULL) &&
 851             (pthread_key_delete != NULL) &&
 852             (pthread_mutex_init != NULL) &&
 853             (pthread_mutex_destroy != NULL) &&
 854             (pthread_mutex_lock != NULL) &&
 855             (pthread_mutex_unlock != NULL) &&
 856             (pthread_cond_init != NULL) &&
 857             (pthread_cond_destroy != NULL) &&
 858             (pthread_cond_wait != NULL) &&
 859             (pthread_equal != NULL) &&
 860             (pthread_self != NULL) &&
 861             (pthread_cond_signal != NULL)) {
 862             libxml_is_threaded = 1;
 863
 864 /* fprintf(stderr, "Running multithreaded\n"); */
 865         } else {
 866
 867 /* fprintf(stderr, "Running without multithread\n"); */
 868             libxml_is_threaded = 0;
 869         }
 870     }
 871 #elif defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
 872     InitializeCriticalSection(&cleanup_helpers_cs);
 873 #endif
 874 }
 875
 876 /**
 877  * xmlCleanupThreads:
 878  *
 879  * xmlCleanupThreads() is used to to cleanup all the thread related
 880  * data of the libxml2 library once processing has ended.
 881  *
 882  * WARNING: if your application is multithreaded or has plugin support
 883  *          calling this may crash the application if another thread or
 884  *          a plugin is still using libxml2. It's sometimes very hard to
 885  *          guess if libxml2 is in use in the application, some libraries
 886  *          or plugins may use it without notice. In case of doubt abstain
 887  *          from calling this function or do it just before calling exit()
 888  *          to avoid leak reports from valgrind !
 889  */
 890 void
 891 xmlCleanupThreads(void)
 892 {
 893 #ifdef DEBUG_THREADS
 894     xmlGenericError(xmlGenericErrorContext, "xmlCleanupThreads()\n");
 895 #endif
 896 #ifdef HAVE_PTHREAD_H
 897     if ((libxml_is_threaded)  && (pthread_key_delete != NULL))
 898         pthread_key_delete(globalkey);
 899     once_control = once_control_init;
 900 #elif defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
 901     if (globalkey != TLS_OUT_OF_INDEXES) {
 902         xmlGlobalStateCleanupHelperParams *p;
 903
 904         EnterCriticalSection(&cleanup_helpers_cs);
 905         p = cleanup_helpers_head;
 906         while (p != NULL) {
 907             xmlGlobalStateCleanupHelperParams *temp = p;
 908
 909             p = p->next;
 910             xmlFreeGlobalState(temp->memory);
 911             free(temp);
 912         }
 913         cleanup_helpers_head = 0;
 914         LeaveCriticalSection(&cleanup_helpers_cs);
 915         TlsFree(globalkey);
 916         globalkey = TLS_OUT_OF_INDEXES;
 917     }
 918     DeleteCriticalSection(&cleanup_helpers_cs);
 919 #endif
 920 }
 921
 922 #ifdef LIBXML_THREAD_ENABLED
 923
 924 /**
 925  * xmlOnceInit
 926  *
 927  * xmlOnceInit() is used to initialize the value of mainthread for use
 928  * in other routines. This function should only be called using
 929  * pthread_once() in association with the once_control variable to ensure
 930  * that the function is only called once. See man pthread_once for more
 931  * details.
 932  */
 933 static void
 934 xmlOnceInit(void)
 935 {
 936 #ifdef HAVE_PTHREAD_H
 937     (void) pthread_key_create(&globalkey, xmlFreeGlobalState);
 938     mainthread = pthread_self();
 939     __xmlInitializeDict();
 940 #elif defined(HAVE_WIN32_THREADS)
 941     if (!run_once.done) {
 942         if (InterlockedIncrement(&run_once.control) == 1) {
 943 #if !defined(HAVE_COMPILER_TLS)
 944             globalkey = TlsAlloc();
 945 #endif
 946             mainthread = GetCurrentThreadId();
 947             __xmlInitializeDict();
 948             run_once.done = 1;
 949         } else {
 950             /* Another thread is working; give up our slice and
 951              * wait until they're done. */
 952             while (!run_once.done)
 953                 Sleep(0);
 954         }
 955     }
 956 #elif defined HAVE_BEOS_THREADS
 957     if (atomic_add(&run_once_init, 1) == 0) {
 958         globalkey = tls_allocate();
 959         tls_set(globalkey, NULL);
 960         mainthread = find_thread(NULL);
 961         __xmlInitializeDict();
 962     } else
 963         atomic_add(&run_once_init, -1);
 964 #endif
 965 }
 966 #endif
 967
 968 /**
 969  * DllMain:
 970  * @hinstDLL: handle to DLL instance
 971  * @fdwReason: Reason code for entry
 972  * @lpvReserved: generic pointer (depends upon reason code)
 973  *
 974  * Entry point for Windows library. It is being used to free thread-specific
 975  * storage.
 976  *
 977  * Returns TRUE always
 978  */
 979 #ifdef HAVE_PTHREAD_H
 980 #elif defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
 981 #if defined(LIBXML_STATIC_FOR_DLL)
 982 BOOL XMLCALL
 983 xmlDllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 984 #else
 985 BOOL WINAPI
 986 DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved)
 987 #endif
 988 {
 989     switch (fdwReason) {
 990         case DLL_THREAD_DETACH:
 991             if (globalkey != TLS_OUT_OF_INDEXES) {
 992                 xmlGlobalState *globalval = NULL;
 993                 xmlGlobalStateCleanupHelperParams *p =
 994                     (xmlGlobalStateCleanupHelperParams *)
 995                     TlsGetValue(globalkey);
 996                 globalval = (xmlGlobalState *) (p ? p->memory : NULL);
 997                 if (globalval) {
 998                     xmlFreeGlobalState(globalval);
 999                     TlsSetValue(globalkey, NULL);
1000                 }
1001                 if (p) {
1002                     EnterCriticalSection(&cleanup_helpers_cs);
1003                     if (p == cleanup_helpers_head)
1004                         cleanup_helpers_head = p->next;
1005                     else
1006                         p->prev->next = p->next;
1007                     if (p->next != NULL)
1008                         p->next->prev = p->prev;
1009                     LeaveCriticalSection(&cleanup_helpers_cs);
1010                     free(p);
1011                 }
1012             }
1013             break;
1014     }
1015     return TRUE;
1016 }
1017 #endif
1018 #define bottom_threads
1019 #include "elfgcchack.h"