/**
 * threads.c: set of generic threading related routines 
 *
 * See Copyright for the status of this software.
 *
 * Gary Pennington <Gary.Pennington@uk.sun.com>
 * daniel@veillard.com
 */

#define IN_LIBXML
#include "libxml.h"

#include <string.h>

#include <libxml/threads.h>
#include <libxml/globals.h>

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_PTHREAD_H
#include <pthread.h>
#endif

#ifdef HAVE_WIN32_THREADS
#include <windows.h>
#ifndef HAVE_COMPILER_TLS
#include <process.h>
#endif
#endif

#ifdef HAVE_BEOS_THREADS
#include <OS.h>
#include <TLS.h>
#endif

#if defined(SOLARIS)
#include <note.h>
#endif

/* #define DEBUG_THREADS */

#ifdef HAVE_PTHREAD_H

static int libxml_is_threaded = -1;
#ifdef __GNUC__
#ifdef linux
#if (__GNUC__ == 3 && __GNUC_MINOR__ >= 3) || (__GNUC__ > 3)
extern int pthread_once (pthread_once_t *__once_control,
                         void (*__init_routine) (void))
           __attribute((weak));
extern void *pthread_getspecific (pthread_key_t __key)
           __attribute((weak));
extern int pthread_setspecific (pthread_key_t __key,
                                __const void *__pointer)
           __attribute((weak));
extern int pthread_key_create (pthread_key_t *__key,
                               void (*__destr_function) (void *))
           __attribute((weak));
extern int pthread_mutex_init ()
           __attribute((weak));
extern int pthread_mutex_destroy ()
           __attribute((weak));
extern int pthread_mutex_lock ()
           __attribute((weak));
extern int pthread_mutex_unlock ()
           __attribute((weak));
extern int pthread_cond_init ()
           __attribute((weak));
extern int pthread_equal ()
           __attribute((weak));
extern pthread_t pthread_self ()
           __attribute((weak));
extern int pthread_key_create ()
           __attribute((weak));
extern int pthread_cond_signal ()
           __attribute((weak));
#endif
#endif /* linux */
#endif /* __GNUC__ */
#endif /* HAVE_PTHREAD_H */

/*
 * TODO: this module still uses malloc/free and not xmlMalloc/xmlFree
 *       to avoid some crazyness since xmlMalloc/xmlFree may actually
 *       be hosted on allocated blocks needing them for the allocation ...
 */

/*
 * xmlMutex are a simple mutual exception locks
 */
struct _xmlMutex {
#ifdef HAVE_PTHREAD_H
    pthread_mutex_t lock;
#elif defined HAVE_WIN32_THREADS
    HANDLE mutex;
#elif defined HAVE_BEOS_THREADS
        sem_id sem;
        thread_id tid;
#else
    int empty;
#endif
};

/*
 * xmlRMutex are reentrant mutual exception locks
 */
struct _xmlRMutex {
#ifdef HAVE_PTHREAD_H
    pthread_mutex_t lock;
    unsigned int    held;
    unsigned int    waiters;
    pthread_t       tid;
    pthread_cond_t  cv;
#elif defined HAVE_WIN32_THREADS
    CRITICAL_SECTION cs;
    unsigned int count;
#elif defined HAVE_BEOS_THREADS
        xmlMutexPtr lock;
        thread_id tid;
        int32 count;
#else
    int empty;
#endif
};
/*
 * This module still has some internal static data.
 *   - xmlLibraryLock a global lock
 *   - globalkey used for per-thread data
 */

#ifdef HAVE_PTHREAD_H
static pthread_key_t    globalkey;
static pthread_t        mainthread;
static pthread_once_t once_control = PTHREAD_ONCE_INIT;
#elif defined HAVE_WIN32_THREADS
#if defined(HAVE_COMPILER_TLS)
static __declspec(thread) xmlGlobalState tlstate;
static __declspec(thread) int tlstate_inited = 0;
#else /* HAVE_COMPILER_TLS */
static DWORD globalkey = TLS_OUT_OF_INDEXES;
#endif /* HAVE_COMPILER_TLS */
static DWORD mainthread;
static struct
{
    DWORD done;
    DWORD control;
} run_once = { 0, 0 };
/* endif HAVE_WIN32_THREADS */
#elif defined HAVE_BEOS_THREADS
int32 globalkey = 0;
thread_id mainthread = 0;
int32 run_once_init = 0;
#endif

static xmlRMutexPtr     xmlLibraryLock = NULL;
#ifdef LIBXML_THREAD_ENABLED
static void xmlOnceInit(void);
#endif

/**
 * xmlNewMutex:
 *
 * xmlNewMutex() is used to allocate a libxml2 token struct for use in
 * synchronizing access to data.
 *
 * Returns a new simple mutex pointer or NULL in case of error
 */
xmlMutexPtr
xmlNewMutex(void)
{
    xmlMutexPtr tok;

    if ((tok = malloc(sizeof(xmlMutex))) == NULL)
        return (NULL);
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0)
        pthread_mutex_init(&tok->lock, NULL);
#elif defined HAVE_WIN32_THREADS
    tok->mutex = CreateMutex(NULL, FALSE, NULL);
#elif defined HAVE_BEOS_THREADS
        if ((tok->sem = create_sem(1, "xmlMutex")) < B_OK) {
                free(tok);
                return NULL;
        }
        tok->tid = -1;
#endif
    return (tok);
}

/**
 * xmlFreeMutex:
 * @tok:  the simple mutex
 *
 * xmlFreeMutex() is used to reclaim resources associated with a libxml2 token
 * struct.
 */
void
xmlFreeMutex(xmlMutexPtr tok)
{
    if (tok == NULL) return;

#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0)
        pthread_mutex_destroy(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    CloseHandle(tok->mutex);
#elif defined HAVE_BEOS_THREADS
        delete_sem(tok->sem);
#endif
    free(tok);
}

/**
 * xmlMutexLock:
 * @tok:  the simple mutex
 *
 * xmlMutexLock() is used to lock a libxml2 token.
 */
void
xmlMutexLock(xmlMutexPtr tok)
{
    if (tok == NULL)
        return;
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0)
        pthread_mutex_lock(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    WaitForSingleObject(tok->mutex, INFINITE);
#elif defined HAVE_BEOS_THREADS
        if (acquire_sem(tok->sem) != B_NO_ERROR) {
#ifdef DEBUG_THREADS
                xmlGenericError(xmlGenericErrorContext, "xmlMutexLock():BeOS:Couldn't aquire semaphore\n");
                exit();
#endif
        }
        tok->tid = find_thread(NULL);
#endif

}

/**
 * xmlMutexUnlock:
 * @tok:  the simple mutex
 *
 * xmlMutexUnlock() is used to unlock a libxml2 token.
 */
void
xmlMutexUnlock(xmlMutexPtr tok)
{
    if (tok == NULL)
        return;
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0)
        pthread_mutex_unlock(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    ReleaseMutex(tok->mutex);
#elif defined HAVE_BEOS_THREADS
        if (tok->tid == find_thread(NULL)) {
                tok->tid = -1;
                release_sem(tok->sem);
        }
#endif
}

/**
 * xmlNewRMutex:
 *
 * xmlRNewMutex() is used to allocate a reentrant mutex for use in
 * synchronizing access to data. token_r is a re-entrant lock and thus useful
 * for synchronizing access to data structures that may be manipulated in a
 * recursive fashion.
 *
 * Returns the new reentrant mutex pointer or NULL in case of error
 */
xmlRMutexPtr
xmlNewRMutex(void)
{
    xmlRMutexPtr tok;

    if ((tok = malloc(sizeof(xmlRMutex))) == NULL)
        return (NULL);
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0) {
        pthread_mutex_init(&tok->lock, NULL);
        tok->held = 0;
        tok->waiters = 0;
        pthread_cond_init(&tok->cv, NULL);
    }
#elif defined HAVE_WIN32_THREADS
    InitializeCriticalSection(&tok->cs);
    tok->count = 0;
#elif defined HAVE_BEOS_THREADS
        if ((tok->lock = xmlNewMutex()) == NULL) {
                free(tok);
                return NULL;
        }
        tok->count = 0;
#endif
    return (tok);
}

/**
 * xmlFreeRMutex:
 * @tok:  the reentrant mutex
 *
 * xmlRFreeMutex() is used to reclaim resources associated with a
 * reentrant mutex.
 */
void
xmlFreeRMutex(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
{
    if (tok == NULL)
        return;
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0) {
        pthread_mutex_destroy(&tok->lock);
        pthread_cond_destroy(&tok->cv);
    }
#elif defined HAVE_WIN32_THREADS
    DeleteCriticalSection(&tok->cs);
#elif defined HAVE_BEOS_THREADS
        xmlFreeMutex(tok->lock);
#endif
    free(tok);
}

/**
 * xmlRMutexLock:
 * @tok:  the reentrant mutex
 *
 * xmlRMutexLock() is used to lock a libxml2 token_r.
 */
void
xmlRMutexLock(xmlRMutexPtr tok)
{
    if (tok == NULL)
        return;
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded == 0)
        return;

    pthread_mutex_lock(&tok->lock);
    if (tok->held) {
        if (pthread_equal(tok->tid, pthread_self())) {
            tok->held++;
            pthread_mutex_unlock(&tok->lock);
            return;
        } else {
            tok->waiters++;
            while (tok->held)
                pthread_cond_wait(&tok->cv, &tok->lock);
            tok->waiters--;
        }
    }
    tok->tid = pthread_self();
    tok->held = 1;
    pthread_mutex_unlock(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    EnterCriticalSection(&tok->cs);
    ++tok->count;
#elif defined HAVE_BEOS_THREADS
        if (tok->lock->tid == find_thread(NULL)) {
                tok->count++;
                return;
        } else {
                xmlMutexLock(tok->lock);
                tok->count = 1;
        }
#endif
}

/**
 * xmlRMutexUnlock:
 * @tok:  the reentrant mutex
 *
 * xmlRMutexUnlock() is used to unlock a libxml2 token_r.
 */
void
xmlRMutexUnlock(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
{
    if (tok == NULL)
        return;
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded == 0)
        return;
    
    pthread_mutex_lock(&tok->lock);
    tok->held--;
    if (tok->held == 0) {
        if (tok->waiters)
            pthread_cond_signal(&tok->cv);
        tok->tid = 0;
    }
    pthread_mutex_unlock(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    if (!--tok->count) 
        LeaveCriticalSection(&tok->cs);
#elif defined HAVE_BEOS_THREADS
        if (tok->lock->tid == find_thread(NULL)) {
                tok->count--;
                if (tok->count == 0) {
                        xmlMutexUnlock(tok->lock);
                }
                return;
        }
#endif
}

/************************************************************************
 *                                                                      *
 *                      Per thread global state handling                *
 *                                                                      *
 ************************************************************************/

#ifdef LIBXML_THREAD_ENABLED
#ifdef xmlLastError
#undef xmlLastError
#endif
/**
 * xmlFreeGlobalState:
 * @state:  a thread global state
 *
 * xmlFreeGlobalState() is called when a thread terminates with a non-NULL
 * global state. It is is used here to reclaim memory resources.
 */
static void
xmlFreeGlobalState(void *state)
{
    xmlGlobalState *gs = (xmlGlobalState *) state;

    /* free any memory allocated in the thread's xmlLastError */
    xmlResetError(&(gs->xmlLastError));
    free(state);
}

/**
 * xmlNewGlobalState:
 *
 * xmlNewGlobalState() allocates a global state. This structure is used to
 * hold all data for use by a thread when supporting backwards compatibility
 * of libxml2 to pre-thread-safe behaviour.
 *
 * Returns the newly allocated xmlGlobalStatePtr or NULL in case of error
 */
static xmlGlobalStatePtr
xmlNewGlobalState(void)
{
    xmlGlobalState *gs;
    
    gs = malloc(sizeof(xmlGlobalState));
    if (gs == NULL)
        return(NULL);

    memset(gs, 0, sizeof(xmlGlobalState));
    xmlInitializeGlobalState(gs);
    return (gs);
}
#endif /* LIBXML_THREAD_ENABLED */


#ifdef HAVE_WIN32_THREADS
#if !defined(HAVE_COMPILER_TLS)
#if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
typedef struct _xmlGlobalStateCleanupHelperParams
{
    HANDLE thread;
    void *memory;
} xmlGlobalStateCleanupHelperParams;

static void XMLCDECL xmlGlobalStateCleanupHelper (void *p)
{
    xmlGlobalStateCleanupHelperParams *params = (xmlGlobalStateCleanupHelperParams *) p;
    WaitForSingleObject(params->thread, INFINITE);
    CloseHandle(params->thread);
    xmlFreeGlobalState(params->memory);
    free(params);
    _endthread();
}
#else /* LIBXML_STATIC && !LIBXML_STATIC_FOR_DLL */

typedef struct _xmlGlobalStateCleanupHelperParams
{
    void *memory;
    struct _xmlGlobalStateCleanupHelperParams * prev;
    struct _xmlGlobalStateCleanupHelperParams * next;
} xmlGlobalStateCleanupHelperParams;

static xmlGlobalStateCleanupHelperParams * cleanup_helpers_head = NULL;
static CRITICAL_SECTION cleanup_helpers_cs;

#endif /* LIBXMLSTATIC && !LIBXML_STATIC_FOR_DLL */
#endif /* HAVE_COMPILER_TLS */
#endif /* HAVE_WIN32_THREADS */

#if defined HAVE_BEOS_THREADS
/**
 * xmlGlobalStateCleanup:
 * @data: unused parameter
 *
 * Used for Beos only
 */
void xmlGlobalStateCleanup(void *data)
{
        void *globalval = tls_get(globalkey);
        if (globalval != NULL)
                xmlFreeGlobalState(globalval);
}
#endif

/**
 * xmlGetGlobalState:
 *
 * xmlGetGlobalState() is called to retrieve the global state for a thread.
 *
 * Returns the thread global state or NULL in case of error
 */
xmlGlobalStatePtr
xmlGetGlobalState(void)
{
#ifdef HAVE_PTHREAD_H
    xmlGlobalState *globalval;

    if (libxml_is_threaded == 0)
        return(NULL);

    pthread_once(&once_control, xmlOnceInit);

    if ((globalval = (xmlGlobalState *)
                pthread_getspecific(globalkey)) == NULL) {
        xmlGlobalState *tsd = xmlNewGlobalState();

        pthread_setspecific(globalkey, tsd);
        return (tsd);
    }
    return (globalval);
#elif defined HAVE_WIN32_THREADS
#if defined(HAVE_COMPILER_TLS)
    if (!tlstate_inited) {
        tlstate_inited = 1;
        xmlInitializeGlobalState(&tlstate);
    }
    return &tlstate;
#else /* HAVE_COMPILER_TLS */
    xmlGlobalState *globalval;
    xmlGlobalStateCleanupHelperParams * p;

    xmlOnceInit();
#if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
    globalval = (xmlGlobalState *)TlsGetValue(globalkey);
#else
    p = (xmlGlobalStateCleanupHelperParams*)TlsGetValue(globalkey);
    globalval = (xmlGlobalState *)(p ? p->memory : NULL);
#endif
    if (globalval == NULL) {
        xmlGlobalState *tsd = xmlNewGlobalState();
        p = (xmlGlobalStateCleanupHelperParams *) malloc(sizeof(xmlGlobalStateCleanupHelperParams));
        p->memory = tsd;
#if defined(LIBXML_STATIC) && !defined(LIBXML_STATIC_FOR_DLL)
        DuplicateHandle(GetCurrentProcess(), GetCurrentThread(), 
                GetCurrentProcess(), &p->thread, 0, TRUE, DUPLICATE_SAME_ACCESS);
        TlsSetValue(globalkey, tsd);
        _beginthread(xmlGlobalStateCleanupHelper, 0, p);
#else
        EnterCriticalSection(&cleanup_helpers_cs);      
        if (cleanup_helpers_head != NULL) {
            cleanup_helpers_head->prev = p;
        }
        p->next = cleanup_helpers_head;
        p->prev = NULL;
        cleanup_helpers_head = p;
        TlsSetValue(globalkey, p);
        LeaveCriticalSection(&cleanup_helpers_cs);      
#endif

        return (tsd);
    }
    return (globalval);
#endif /* HAVE_COMPILER_TLS */
#elif defined HAVE_BEOS_THREADS
    xmlGlobalState *globalval;

    xmlOnceInit();

    if ((globalval = (xmlGlobalState *)
                tls_get(globalkey)) == NULL) {
        xmlGlobalState *tsd = xmlNewGlobalState();

        tls_set(globalkey, tsd);
        on_exit_thread(xmlGlobalStateCleanup, NULL);
        return (tsd);
    }
    return (globalval);
#else
    return(NULL);
#endif
}

/************************************************************************
 *                                                                      *
 *                      Library wide thread interfaces                  *
 *                                                                      *
 ************************************************************************/

/**
 * xmlGetThreadId:
 *
 * xmlGetThreadId() find the current thread ID number
 *
 * Returns the current thread ID number
 */
int
xmlGetThreadId(void)
{
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded == 0)
        return(0);
    return((int) pthread_self());
#elif defined HAVE_WIN32_THREADS
    return GetCurrentThreadId();
#elif defined HAVE_BEOS_THREADS
        return find_thread(NULL);
#else
    return((int) 0);
#endif
}

/**
 * xmlIsMainThread:
 *
 * xmlIsMainThread() check whether the current thread is the main thread.
 *
 * Returns 1 if the current thread is the main thread, 0 otherwise
 */
int
xmlIsMainThread(void)
{
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded == -1)
        xmlInitThreads();
    if (libxml_is_threaded == 0)
        return(1);
    pthread_once(&once_control, xmlOnceInit);
#elif defined HAVE_WIN32_THREADS
    xmlOnceInit (); 
#elif defined HAVE_BEOS_THREADS
    xmlOnceInit();
#endif
        
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlIsMainThread()\n");
#endif
#ifdef HAVE_PTHREAD_H
    return(mainthread == pthread_self());
#elif defined HAVE_WIN32_THREADS
    return(mainthread == GetCurrentThreadId ());
#elif defined HAVE_BEOS_THREADS
        return(mainthread == find_thread(NULL));
#else
    return(1);
#endif
}

/**
 * xmlLockLibrary:
 *
 * xmlLockLibrary() is used to take out a re-entrant lock on the libxml2
 * library.
 */
void
xmlLockLibrary(void)
{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlLockLibrary()\n");
#endif
    xmlRMutexLock(xmlLibraryLock);
}

/**
 * xmlUnlockLibrary:
 *
 * xmlUnlockLibrary() is used to release a re-entrant lock on the libxml2
 * library.
 */
void
xmlUnlockLibrary(void)
{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlUnlockLibrary()\n");
#endif
    xmlRMutexUnlock(xmlLibraryLock);
}

/**
 * xmlInitThreads:
 *
 * xmlInitThreads() is used to to initialize all the thread related
 * data of the libxml2 library.
 */
void
xmlInitThreads(void)
{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlInitThreads()\n");
#endif
#if defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
    InitializeCriticalSection(&cleanup_helpers_cs);
#endif
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded == -1) {
        if ((pthread_once != NULL) &&
            (pthread_getspecific != NULL) &&
            (pthread_setspecific != NULL) &&
            (pthread_key_create != NULL) &&
            (pthread_mutex_init != NULL) &&
            (pthread_mutex_destroy != NULL) &&
            (pthread_mutex_lock != NULL) &&
            (pthread_mutex_unlock != NULL) &&
            (pthread_cond_init != NULL) &&
            (pthread_equal != NULL) &&
            (pthread_self != NULL) &&
            (pthread_key_create != NULL) &&
            (pthread_cond_signal != NULL)) {
            libxml_is_threaded = 1;
/* fprintf(stderr, "Running multithreaded\n"); */
        } else {
/* fprintf(stderr, "Running without multithread\n"); */
            libxml_is_threaded = 0;
        }
    }
#endif
}

/**
 * xmlCleanupThreads:
 *
 * xmlCleanupThreads() is used to to cleanup all the thread related
 * data of the libxml2 library once processing has ended.
 */
void
xmlCleanupThreads(void)
{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlCleanupThreads()\n");
#endif
#if defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
    if (globalkey != TLS_OUT_OF_INDEXES) {
        xmlGlobalStateCleanupHelperParams * p;
        EnterCriticalSection(&cleanup_helpers_cs);
        p = cleanup_helpers_head;
        while (p != NULL) {
                xmlGlobalStateCleanupHelperParams * temp = p;
                p = p->next;
                xmlFreeGlobalState(temp->memory);
                free(temp);
        }
        cleanup_helpers_head = 0;
        LeaveCriticalSection(&cleanup_helpers_cs);
        TlsFree(globalkey);
        globalkey = TLS_OUT_OF_INDEXES;
    }
    DeleteCriticalSection(&cleanup_helpers_cs);
#endif
}

#ifdef LIBXML_THREAD_ENABLED
/**
 * xmlOnceInit
 *
 * xmlOnceInit() is used to initialize the value of mainthread for use
 * in other routines. This function should only be called using
 * pthread_once() in association with the once_control variable to ensure
 * that the function is only called once. See man pthread_once for more
 * details.
 */
static void
xmlOnceInit(void) {
#ifdef HAVE_PTHREAD_H
    (void) pthread_key_create(&globalkey, xmlFreeGlobalState);
    mainthread = pthread_self();
#endif

#if defined(HAVE_WIN32_THREADS)
    if (!run_once.done) {
        if (InterlockedIncrement(&run_once.control) == 1)
        {
#if !defined(HAVE_COMPILER_TLS)
            globalkey = TlsAlloc();
#endif
            mainthread = GetCurrentThreadId();
            run_once.done = 1;
        }
        else {
            /* Another thread is working; give up our slice and
             * wait until they're done. */
            while (!run_once.done)
                Sleep(0);
        }
    }
#endif

#ifdef HAVE_BEOS_THREADS
        if (atomic_add(&run_once_init, 1) == 0) {
                globalkey = tls_allocate();
                tls_set(globalkey, NULL);
                mainthread = find_thread(NULL);
        } else
                atomic_add(&run_once_init, -1);
#endif
}
#endif

/**
 * DllMain:
 * @hinstDLL: handle to DLL instance
 * @fdwReason: Reason code for entry
 * @lpvReserved: generic pointer (depends upon reason code)
 *
 * Entry point for Windows library. It is being used to free thread-specific
 * storage.
 *
 * Returns TRUE always
 */
#if defined(HAVE_WIN32_THREADS) && !defined(HAVE_COMPILER_TLS) && (!defined(LIBXML_STATIC) || defined(LIBXML_STATIC_FOR_DLL))
#if defined(LIBXML_STATIC_FOR_DLL)
BOOL WINAPI xmlDllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) 
#else
BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) 
#endif
{
    switch(fdwReason) {
    case DLL_THREAD_DETACH:
        if (globalkey != TLS_OUT_OF_INDEXES) {
            xmlGlobalState *globalval = NULL;
            xmlGlobalStateCleanupHelperParams * p =
                (xmlGlobalStateCleanupHelperParams*)TlsGetValue(globalkey);
            globalval = (xmlGlobalState *)(p ? p->memory : NULL);
            if (globalval) {
                xmlFreeGlobalState(globalval);
                TlsSetValue(globalkey,NULL);
            }
            if (p)
            {
                EnterCriticalSection(&cleanup_helpers_cs);
                if (p == cleanup_helpers_head)
                    cleanup_helpers_head = p->next;
                else
                    p->prev->next = p->next;
                if (p->next != NULL)
                    p->next->prev = p->prev;
                LeaveCriticalSection(&cleanup_helpers_cs);
                free(p);
            }
        }
        break;
    }
    return TRUE;
}
#endif
#define bottom_threads
#include "elfgcchack.h"