shaba/libxml2
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/libxml2.git synced 2025-02-04 01:47:02 +03:00
Code

Revert "Simplify recursive pthread mutex"

Browse Source 
This reverts commit 5ffe2981b7d0547dd957a61ac6e1e3db829748d1.
This reverts commit 4adb7677635b2c8d764767f6b484de1b26217f5d.

Recursive mutexes are an XSI extension, so better not rely on them.
This commit is contained in:
Nick Wellnhofer 2022-03-18 15:46:30 +01:00
parent 2070ade6df
commit 83d5a87e37
1 changed files with 54 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

71
threads.c
View File

@ -46,20 +46,23 @@ static int libxml_is_threaded = -1;
#define XML_PTHREAD_WEAK
#pragma weak pthread_equal
#pragma weak pthread_once
#pragma weak pthread_getspecific
#pragma weak pthread_setspecific
#pragma weak pthread_key_create
#pragma weak pthread_key_delete
#pragma weak pthread_mutex_destroy
#pragma weak pthread_mutex_init
#pragma weak pthread_mutex_destroy
#pragma weak pthread_mutex_lock
#pragma weak pthread_mutex_unlock
#pragma weak pthread_mutexattr_destroy
#pragma weak pthread_mutexattr_init
#pragma weak pthread_mutexattr_settype
#pragma weak pthread_once
#pragma weak pthread_cond_init
#pragma weak pthread_cond_destroy
#pragma weak pthread_cond_wait
#pragma weak pthread_equal
#pragma weak pthread_self
#pragma weak pthread_setspecific
#pragma weak pthread_key_create
#pragma weak pthread_key_delete
#pragma weak pthread_cond_signal
#else /* __GNUC__, __GLIBC__, __linux__ */
@ -97,6 +100,10 @@ struct _xmlMutex {
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;
#elif defined HAVE_BEOS_THREADS
@ -274,11 +281,10 @@ xmlNewRMutex(void)
return (NULL);
#ifdef HAVE_PTHREAD_H
if (libxml_is_threaded != 0) {
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
pthread_mutex_init(&tok->lock, &attr);
pthread_mutexattr_destroy(&attr);
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);
@ -307,6 +313,7 @@ xmlFreeRMutex(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
#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);
@ -328,8 +335,25 @@ xmlRMutexLock(xmlRMutexPtr tok)
if (tok == NULL)
return;
#ifdef HAVE_PTHREAD_H
if (libxml_is_threaded != 0)
pthread_mutex_lock(&tok->lock);
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);
#elif defined HAVE_BEOS_THREADS
@ -355,8 +379,17 @@ xmlRMutexUnlock(xmlRMutexPtr tok ATTRIBUTE_UNUSED)
if (tok == NULL)
return;
#ifdef HAVE_PTHREAD_H
if (libxml_is_threaded != 0)
pthread_mutex_unlock(&tok->lock);
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
LeaveCriticalSection(&tok->cs);
#elif defined HAVE_BEOS_THREADS
@ -825,8 +858,12 @@ xmlInitThreads(void)
(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_self != NULL) &&
(pthread_cond_signal != NULL)) {
libxml_is_threaded = 1;
/* fprintf(stderr, "Running multithreaded\n"); */