threads.c File Reference

#include "libxml.h"
#include <string.h>
#include <libxml/threads.h>
#include <libxml/globals.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include "elfgcchack.h"

Include dependency graph for threads.c:

Go to the source code of this file.

Classes
struct	_xmlMutex
struct	_xmlRMutex

Macros
#define	IN_LIBXML
#define	bottom_threads

Functions
xmlMutexPtr	xmlNewMutex (void)
void	xmlFreeMutex (xmlMutexPtr tok)
void	xmlMutexLock (xmlMutexPtr tok)
void	xmlMutexUnlock (xmlMutexPtr tok)
xmlRMutexPtr	xmlNewRMutex (void)
void	xmlFreeRMutex (xmlRMutexPtr tok ATTRIBUTE_UNUSED)
void	xmlRMutexLock (xmlRMutexPtr tok)
void	xmlRMutexUnlock (xmlRMutexPtr tok ATTRIBUTE_UNUSED)
void	__xmlGlobalInitMutexLock (void)
void	__xmlGlobalInitMutexUnlock (void)
void	__xmlGlobalInitMutexDestroy (void)
xmlGlobalStatePtr	xmlGetGlobalState (void)
int	xmlGetThreadId (void)
int	xmlIsMainThread (void)
void	xmlLockLibrary (void)
void	xmlUnlockLibrary (void)
void	xmlInitThreads (void)
void	xmlCleanupThreads (void)

Variables
static xmlRMutexPtr	xmlLibraryLock = NULL

Macro Definition Documentation

bottom_threads

#define bottom_threads

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

Definition at line 1048 of file threads.c.

IN_LIBXML

#define IN_LIBXML

threads.c: set of generic threading related routines

See Copyright for the status of this software.

Gary Pennington Gary..nosp@m.Penn.nosp@m.ingto.nosp@m.n@uk.nosp@m..sun..nosp@m.com danie.nosp@m.l@ve.nosp@m.illar.nosp@m.d.co.nosp@m.m

Definition at line 10 of file threads.c.

Function Documentation

__xmlGlobalInitMutexDestroy()

void __xmlGlobalInitMutexDestroy

(

void

)

xmlGlobalInitMutexDestroy

Makes sure that the global initialization mutex is destroyed before application termination.

Definition at line 526 of file threads.c.

{
#ifdef HAVE_PTHREAD_H
#elif defined HAVE_WIN32_THREADS
    if (global_init_lock != NULL) {
        DeleteCriticalSection(global_init_lock);
        free(global_init_lock);
        global_init_lock = NULL;
    }
#endif
}

Referenced by xmlCleanupGlobals().

__xmlGlobalInitMutexLock()

void __xmlGlobalInitMutexLock

(

void

)

xmlGlobalInitMutexLock

Makes sure that the global initialization mutex is initialized and locks it.

Definition at line 427 of file threads.c.

{
    /* Make sure the global init lock is initialized and then lock it. */
#ifdef HAVE_PTHREAD_H
    /* The mutex is statically initialized, so we just lock it. */
#ifdef XML_PTHREAD_WEAK
    if (pthread_mutex_lock == NULL)
        return;
#endif /* XML_PTHREAD_WEAK */
    pthread_mutex_lock(&global_init_lock);
#elif defined HAVE_WIN32_THREADS
    LPCRITICAL_SECTION cs;

    /* Create a new critical section */
    if (global_init_lock == NULL) {
        cs = malloc(sizeof(CRITICAL_SECTION));
        if (cs == NULL) {
            xmlGenericError(xmlGenericErrorContext,
                            "xmlGlobalInitMutexLock: out of memory\n");
            return;
        }
        InitializeCriticalSection(cs);

        /* Swap it into the global_init_lock */
#ifdef InterlockedCompareExchangePointer
        InterlockedCompareExchangePointer((void **) &global_init_lock,
                                          cs, NULL);
#else /* Use older void* version */
        InterlockedCompareExchange((void **) &global_init_lock,
                                   (void *) cs, NULL);
#endif /* InterlockedCompareExchangePointer */

        /* If another thread successfully recorded its critical
         * section in the global_init_lock then discard the one
         * allocated by this thread. */
        if (global_init_lock != cs) {
            DeleteCriticalSection(cs);
            free(cs);
        }
    }

    /* Lock the chosen critical section */
    EnterCriticalSection(global_init_lock);
#elif defined HAVE_BEOS_THREADS
    int32 sem;

    /* Allocate a new semaphore */
    sem = create_sem(1, "xmlGlobalinitMutex");

    while (global_init_lock == -1) {
        if (atomic_add(&global_init_count, 1) == 0) {
            global_init_lock = sem;
        } else {
            snooze(1);
            atomic_add(&global_init_count, -1);
        }
    }

    /* If another thread successfully recorded its critical
     * section in the global_init_lock then discard the one
     * allocated by this thread. */
    if (global_init_lock != sem)
        delete_sem(sem);

    /* Acquire the chosen semaphore */
    if (acquire_sem(global_init_lock) != B_NO_ERROR) {
#ifdef DEBUG_THREADS
        xmlGenericError(xmlGenericErrorContext,
                        "xmlGlobalInitMutexLock():BeOS:Couldn't acquire semaphore\n");
#endif
    }
#endif
}

Referenced by xmlInitParser().

__xmlGlobalInitMutexUnlock()

void __xmlGlobalInitMutexUnlock

(

void

)

Definition at line 502 of file threads.c.

{
#ifdef HAVE_PTHREAD_H
#ifdef XML_PTHREAD_WEAK
    if (pthread_mutex_unlock == NULL)
        return;
#endif /* XML_PTHREAD_WEAK */
    pthread_mutex_unlock(&global_init_lock);
#elif defined HAVE_WIN32_THREADS
    if (global_init_lock != NULL) {
    LeaveCriticalSection(global_init_lock);
    }
#elif defined HAVE_BEOS_THREADS
    release_sem(global_init_lock);
#endif
}

Referenced by xmlInitParser().

xmlCleanupThreads()

void xmlCleanupThreads

(

void

)

xmlCleanupThreads:

xmlCleanupThreads() is used to to cleanup all the thread related data of the libxml2 library once processing has ended.

WARNING: if your application is multithreaded or has plugin support calling this may crash the application if another thread or a plugin is still using libxml2. It's sometimes very hard to guess if libxml2 is in use in the application, some libraries or plugins may use it without notice. In case of doubt abstain from calling this function or do it just before calling exit() to avoid leak reports from valgrind !

Definition at line 906 of file threads.c.

{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlCleanupThreads()\n");
#endif
#ifdef HAVE_PTHREAD_H
    if (libxml_is_threaded != 0)
        pthread_key_delete(globalkey);
    once_control = once_control_init;
#elif 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
}

Referenced by xmlCleanupParser().

xmlFreeMutex()

void xmlFreeMutex

(

xmlMutexPtr

tok

)

xmlFreeMutex: @tok: the simple mutex

xmlFreeMutex() is used to reclaim resources associated with a libxml2 token struct.

Definition at line 206 of file threads.c.

{
    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);
}

Referenced by xmlCleanupGlobals(), xmlCleanupMemory(), xmlFreeRMutex(), and xsltCleanupGlobals().

xmlFreeRMutex()

void xmlFreeRMutex

(

xmlRMutexPtr tok

ATTRIBUTE_UNUSED

)

xmlFreeRMutex: @tok: the reentrant mutex

xmlRFreeMutex() is used to reclaim resources associated with a reentrant mutex.

Definition at line 319 of file threads.c.

{
    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);
}

Referenced by xmlDictCleanup(), and xsltUninit().

xmlGetGlobalState()

xmlGlobalStatePtr xmlGetGlobalState

(

void

)

xmlGetGlobalState:

xmlGetGlobalState() is called to retrieve the global state for a thread.

Returns the thread global state or NULL in case of error

Definition at line 654 of file threads.c.

{
#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();
    if (tsd == NULL)
        return(NULL);

        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();

        if (tsd == NULL)
        return(NULL);
        p = (xmlGlobalStateCleanupHelperParams *)
            malloc(sizeof(xmlGlobalStateCleanupHelperParams));
    if (p == NULL) {
            xmlGenericError(xmlGenericErrorContext,
                            "xmlGetGlobalState: out of memory\n");
            xmlFreeGlobalState(tsd);
        return(NULL);
    }
        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();
    if (tsd == NULL)
        return (NULL);

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

Referenced by __oldXMLWDcompatibility(), __xmlBufferAllocScheme(), __xmlDefaultBufferSize(), __xmlDefaultSAXLocator(), __xmlDeregisterNodeDefaultValue(), __xmlDoValidityCheckingDefaultValue(), __xmlGenericError(), __xmlGenericErrorContext(), __xmlGetWarningsDefaultValue(), __xmlIndentTreeOutput(), __xmlKeepBlanksDefaultValue(), __xmlLastError(), __xmlLineNumbersDefaultValue(), __xmlLoadExtDtdDefaultValue(), __xmlOutputBufferCreateFilenameValue(), __xmlParserDebugEntities(), __xmlParserInputBufferCreateFilenameValue(), __xmlParserVersion(), __xmlPedanticParserDefaultValue(), __xmlRegisterNodeDefaultValue(), __xmlSaveNoEmptyTags(), __xmlStructuredError(), __xmlStructuredErrorContext(), __xmlSubstituteEntitiesDefaultValue(), and __xmlTreeIndentString().

xmlGetThreadId()

int xmlGetThreadId

(

void

)

xmlGetThreadId:

xmlGetThreadId() find the current thread ID number Note that this is likely to be broken on some platforms using pthreads as the specification doesn't mandate pthread_t to be an integer type

Returns the current thread ID number

Definition at line 764 of file threads.c.

{
#ifdef HAVE_PTHREAD_H
    pthread_t id;
    int ret;

    if (libxml_is_threaded == 0)
        return (0);
    id = pthread_self();
    /* horrible but preserves compat, see warning above */
    memcpy(&ret, &id, sizeof(ret));
    return (ret);
#elif defined HAVE_WIN32_THREADS
    return GetCurrentThreadId();
#elif defined HAVE_BEOS_THREADS
    return find_thread(NULL);
#else
    return ((int) 0);
#endif
}

Referenced by xmlInitializeGlobalState().

xmlInitThreads()

void xmlInitThreads

(

void

)

xmlInitThreads:

xmlInitThreads() is used to to initialize all the thread related data of the libxml2 library.

Definition at line 858 of file threads.c.

{
#ifdef HAVE_PTHREAD_H
#ifdef XML_PTHREAD_WEAK
    if (libxml_is_threaded == -1) {
        if ((pthread_once != NULL) &&
            (pthread_getspecific != NULL) &&
            (pthread_setspecific != NULL) &&
            (pthread_key_create != NULL) &&
            (pthread_key_delete != NULL) &&
            (pthread_mutex_init != NULL) &&
            (pthread_mutex_destroy != NULL) &&
            (pthread_mutex_lock != NULL) &&
            (pthread_mutex_unlock != NULL) &&
            (pthread_cond_init != NULL) &&
            (pthread_cond_destroy != NULL) &&
            (pthread_cond_wait != NULL) &&
            (pthread_equal != NULL) &&
            (pthread_self != 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 /* XML_PTHREAD_WEAK */
#endif
}

Referenced by xmlInitParser(), and xmlIsMainThread().

xmlIsMainThread()

int xmlIsMainThread

(

void

)

xmlIsMainThread:

xmlIsMainThread() check whether the current thread is the main thread.

Returns 1 if the current thread is the main thread, 0 otherwise

Definition at line 793 of file threads.c.

{
#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 (pthread_equal(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()

void xmlLockLibrary

(

void

)

xmlLockLibrary:

xmlLockLibrary() is used to take out a re-entrant lock on the libxml2 library.

Definition at line 828 of file threads.c.

{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlLockLibrary()\n");
#endif
    xmlRMutexLock(xmlLibraryLock);
}

xmlMutexLock()

void xmlMutexLock

(

xmlMutexPtr

tok

)

xmlMutexLock: @tok: the simple mutex

xmlMutexLock() is used to lock a libxml2 token.

Definition at line 229 of file threads.c.

{
    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 acquire semaphore\n");
#endif
    }
    tok->tid = find_thread(NULL);
#endif

}

Referenced by xmlInitializeGlobalState(), xmlMallocAtomicLoc(), xmlMallocLoc(), xmlMemBlocks(), xmlMemDisplay(), xmlMemDisplayLast(), xmlMemFree(), xmlMemShow(), xmlMemStrdupLoc(), xmlMemUsed(), xmlReallocLoc(), xmlRMutexLock(), xmlThrDefBufferAllocScheme(), xmlThrDefDefaultBufferSize(), xmlThrDefDeregisterNodeDefault(), xmlThrDefDoValidityCheckingDefaultValue(), xmlThrDefGetWarningsDefaultValue(), xmlThrDefIndentTreeOutput(), xmlThrDefKeepBlanksDefaultValue(), xmlThrDefLineNumbersDefaultValue(), xmlThrDefLoadExtDtdDefaultValue(), xmlThrDefOutputBufferCreateFilenameDefault(), xmlThrDefParserDebugEntities(), xmlThrDefParserInputBufferCreateFilenameDefault(), xmlThrDefPedanticParserDefaultValue(), xmlThrDefRegisterNodeDefault(), xmlThrDefSaveNoEmptyTags(), xmlThrDefSetGenericErrorFunc(), xmlThrDefSetStructuredErrorFunc(), xmlThrDefSubstituteEntitiesDefaultValue(), xmlThrDefTreeIndentString(), xsltCleanupGlobals(), xsltDebugDumpExtensions(), xsltExtModuleElementLookup(), xsltExtModuleElementPreComputeLookup(), xsltExtModuleFunctionLookup(), xsltExtModuleTopLevelLookup(), xsltGetExtData(), xsltPreComputeExtModuleElement(), xsltRegisterExtModuleElement(), xsltRegisterExtModuleFull(), xsltRegisterExtModuleFunction(), xsltRegisterExtModuleTopLevel(), xsltRegisterExtPrefix(), xsltStyleInitializeStylesheetModule(), xsltUnregisterAllExtModuleElement(), xsltUnregisterAllExtModuleFunction(), xsltUnregisterAllExtModules(), xsltUnregisterAllExtModuleTopLevel(), xsltUnregisterExtModule(), xsltUnregisterExtModuleElement(), xsltUnregisterExtModuleFunction(), and xsltUnregisterExtModuleTopLevel().

xmlMutexUnlock()

void xmlMutexUnlock

(

xmlMutexPtr

tok

)

xmlMutexUnlock: @tok: the simple mutex

xmlMutexUnlock() is used to unlock a libxml2 token.

Definition at line 257 of file threads.c.

{
    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
}

Referenced by xmlInitializeGlobalState(), xmlMallocAtomicLoc(), xmlMallocLoc(), xmlMemBlocks(), xmlMemDisplay(), xmlMemDisplayLast(), xmlMemFree(), xmlMemShow(), xmlMemStrdupLoc(), xmlMemUsed(), xmlReallocLoc(), xmlRMutexUnlock(), xmlThrDefBufferAllocScheme(), xmlThrDefDefaultBufferSize(), xmlThrDefDeregisterNodeDefault(), xmlThrDefDoValidityCheckingDefaultValue(), xmlThrDefGetWarningsDefaultValue(), xmlThrDefIndentTreeOutput(), xmlThrDefKeepBlanksDefaultValue(), xmlThrDefLineNumbersDefaultValue(), xmlThrDefLoadExtDtdDefaultValue(), xmlThrDefOutputBufferCreateFilenameDefault(), xmlThrDefParserDebugEntities(), xmlThrDefParserInputBufferCreateFilenameDefault(), xmlThrDefPedanticParserDefaultValue(), xmlThrDefRegisterNodeDefault(), xmlThrDefSaveNoEmptyTags(), xmlThrDefSetGenericErrorFunc(), xmlThrDefSetStructuredErrorFunc(), xmlThrDefSubstituteEntitiesDefaultValue(), xmlThrDefTreeIndentString(), xsltCleanupGlobals(), xsltDebugDumpExtensions(), xsltExtModuleElementLookup(), xsltExtModuleElementPreComputeLookup(), xsltExtModuleFunctionLookup(), xsltExtModuleTopLevelLookup(), xsltGetExtData(), xsltPreComputeExtModuleElement(), xsltRegisterExtModuleElement(), xsltRegisterExtModuleFull(), xsltRegisterExtModuleFunction(), xsltRegisterExtModuleTopLevel(), xsltRegisterExtPrefix(), xsltStyleInitializeStylesheetModule(), xsltUnregisterAllExtModuleElement(), xsltUnregisterAllExtModuleFunction(), xsltUnregisterAllExtModules(), xsltUnregisterAllExtModuleTopLevel(), xsltUnregisterExtModule(), xsltUnregisterExtModuleElement(), xsltUnregisterExtModuleFunction(), and xsltUnregisterExtModuleTopLevel().

xmlNewMutex()

xmlMutexPtr xmlNewMutex

(

void

)

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

Definition at line 177 of file threads.c.

{
    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);
}

Referenced by xmlInitGlobals(), xmlInitMemory(), xmlNewRMutex(), and xsltInitGlobals().

xmlNewRMutex()

xmlRMutexPtr xmlNewRMutex

(

void

)

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

Definition at line 285 of file threads.c.

{
    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);
}

Referenced by __xmlInitializeDict(), and xsltInit().

xmlRMutexLock()

void xmlRMutexLock

(

xmlRMutexPtr

tok

)

xmlRMutexLock: @tok: the reentrant mutex

xmlRMutexLock() is used to lock a libxml2 token_r.

Definition at line 343 of file threads.c.

{
    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
}

Referenced by __xmlInitializeDict(), __xmlRandom(), xmlDictFree(), xmlDictReference(), xmlLockLibrary(), and xsltFreeLocales().

xmlRMutexUnlock()

void xmlRMutexUnlock

(

xmlRMutexPtr tok

ATTRIBUTE_UNUSED

)

xmlRMutexUnlock: @tok: the reentrant mutex

xmlRMutexUnlock() is used to unlock a libxml2 token_r.

Definition at line 388 of file threads.c.

{
    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);
        memset(&tok->tid, 0, sizeof(tok->tid));
    }
    pthread_mutex_unlock(&tok->lock);
#elif defined HAVE_WIN32_THREADS
    if (tok->count > 0) {
    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
}

Referenced by __xmlInitializeDict(), __xmlRandom(), xmlDictFree(), xmlDictReference(), xmlUnlockLibrary(), and xsltFreeLocales().

xmlUnlockLibrary()

void xmlUnlockLibrary

(

void

)

xmlUnlockLibrary:

xmlUnlockLibrary() is used to release a re-entrant lock on the libxml2 library.

Definition at line 843 of file threads.c.

{
#ifdef DEBUG_THREADS
    xmlGenericError(xmlGenericErrorContext, "xmlUnlockLibrary()\n");
#endif
    xmlRMutexUnlock(xmlLibraryLock);
}

Variable Documentation

xmlLibraryLock

xmlRMutexPtr xmlLibraryLock = NULL

static

Definition at line 162 of file threads.c.

Referenced by xmlLockLibrary(), and xmlUnlockLibrary().