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New upstream version 2.3.4

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This commit is contained in:
Jan Wagner 2023-10-18 07:29:37 +00:00
parent e7bdd1c6c6
commit de72f6f588
556 changed files with 90432 additions and 53391 deletions
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866
gl/glthread/lock.c
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@ -1,22 +1,21 @@
/* Locking in multithreaded situations.
Copyright (C) 2005-2013 Free Software Foundation, Inc.
Copyright (C) 2005-2023 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
GNU Lesser General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>. */
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2005.
Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-solaris.h,
gthr-win32.h. */
Based on GCC's gthr-posix.h, gthr-posix95.h. */
#include <config.h>
@ -24,15 +23,267 @@
/* ========================================================================= */
#if USE_ISOC_THREADS || USE_ISOC_AND_POSIX_THREADS
/* -------------------------- gl_lock_t datatype -------------------------- */
int
glthread_lock_init (gl_lock_t *lock)
{
if (mtx_init (&lock->mutex, mtx_plain) != thrd_success)
return ENOMEM;
lock->init_needed = 0;
return 0;
}
int
glthread_lock_lock (gl_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_lock (&lock->mutex) != thrd_success)
return EAGAIN;
return 0;
}
int
glthread_lock_unlock (gl_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_unlock (&lock->mutex) != thrd_success)
return EINVAL;
return 0;
}
int
glthread_lock_destroy (gl_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
mtx_destroy (&lock->mutex);
return 0;
}
/* ------------------------- gl_rwlock_t datatype ------------------------- */
int
glthread_rwlock_init (gl_rwlock_t *lock)
{
if (mtx_init (&lock->lock, mtx_plain) != thrd_success
|| cnd_init (&lock->waiting_readers) != thrd_success
|| cnd_init (&lock->waiting_writers) != thrd_success)
return ENOMEM;
lock->waiting_writers_count = 0;
lock->runcount = 0;
lock->init_needed = 0;
return 0;
}
int
glthread_rwlock_rdlock (gl_rwlock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_lock (&lock->lock) != thrd_success)
return EAGAIN;
/* Test whether only readers are currently running, and whether the runcount
field will not overflow, and whether no writer is waiting. The latter
condition is because POSIX recommends that "write locks shall take
precedence over read locks", to avoid "writer starvation". */
while (!(lock->runcount + 1 > 0 && lock->waiting_writers_count == 0))
{
/* This thread has to wait for a while. Enqueue it among the
waiting_readers. */
if (cnd_wait (&lock->waiting_readers, &lock->lock) != thrd_success)
{
mtx_unlock (&lock->lock);
return EINVAL;
}
}
lock->runcount++;
if (mtx_unlock (&lock->lock) != thrd_success)
return EINVAL;
return 0;
}
int
glthread_rwlock_wrlock (gl_rwlock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_lock (&lock->lock) != thrd_success)
return EAGAIN;
/* Test whether no readers or writers are currently running. */
while (!(lock->runcount == 0))
{
/* This thread has to wait for a while. Enqueue it among the
waiting_writers. */
lock->waiting_writers_count++;
if (cnd_wait (&lock->waiting_writers, &lock->lock) != thrd_success)
{
lock->waiting_writers_count--;
mtx_unlock (&lock->lock);
return EINVAL;
}
lock->waiting_writers_count--;
}
lock->runcount--; /* runcount becomes -1 */
if (mtx_unlock (&lock->lock) != thrd_success)
return EINVAL;
return 0;
}
int
glthread_rwlock_unlock (gl_rwlock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_lock (&lock->lock) != thrd_success)
return EAGAIN;
if (lock->runcount < 0)
{
/* Drop a writer lock. */
if (!(lock->runcount == -1))
{
mtx_unlock (&lock->lock);
return EINVAL;
}
lock->runcount = 0;
}
else
{
/* Drop a reader lock. */
if (!(lock->runcount > 0))
{
mtx_unlock (&lock->lock);
return EINVAL;
}
lock->runcount--;
}
if (lock->runcount == 0)
{
/* POSIX recommends that "write locks shall take precedence over read
locks", to avoid "writer starvation". */
if (lock->waiting_writers_count > 0)
{
/* Wake up one of the waiting writers. */
if (cnd_signal (&lock->waiting_writers) != thrd_success)
{
mtx_unlock (&lock->lock);
return EINVAL;
}
}
else
{
/* Wake up all waiting readers. */
if (cnd_broadcast (&lock->waiting_readers) != thrd_success)
{
mtx_unlock (&lock->lock);
return EINVAL;
}
}
}
if (mtx_unlock (&lock->lock) != thrd_success)
return EINVAL;
return 0;
}
int
glthread_rwlock_destroy (gl_rwlock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
mtx_destroy (&lock->lock);
cnd_destroy (&lock->waiting_readers);
cnd_destroy (&lock->waiting_writers);
return 0;
}
/* --------------------- gl_recursive_lock_t datatype --------------------- */
int
glthread_recursive_lock_init (gl_recursive_lock_t *lock)
{
if (mtx_init (&lock->mutex, mtx_plain | mtx_recursive) != thrd_success)
return ENOMEM;
lock->init_needed = 0;
return 0;
}
int
glthread_recursive_lock_lock (gl_recursive_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_lock (&lock->mutex) != thrd_success)
return EAGAIN;
return 0;
}
int
glthread_recursive_lock_unlock (gl_recursive_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
if (mtx_unlock (&lock->mutex) != thrd_success)
return EINVAL;
return 0;
}
int
glthread_recursive_lock_destroy (gl_recursive_lock_t *lock)
{
if (lock->init_needed)
call_once (&lock->init_once, lock->init_func);
mtx_destroy (&lock->mutex);
return 0;
}
/* -------------------------- gl_once_t datatype -------------------------- */
#endif
/* ========================================================================= */
#if USE_POSIX_THREADS
/* -------------------------- gl_lock_t datatype -------------------------- */
/* ------------------------- gl_rwlock_t datatype ------------------------- */
# if HAVE_PTHREAD_RWLOCK
# if HAVE_PTHREAD_RWLOCK && (HAVE_PTHREAD_RWLOCK_RDLOCK_PREFER_WRITER || (defined PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP && (__GNU_LIBRARY__ > 1)))
# if !defined PTHREAD_RWLOCK_INITIALIZER
# if defined PTHREAD_RWLOCK_INITIALIZER || defined PTHREAD_RWLOCK_INITIALIZER_NP
# if !HAVE_PTHREAD_RWLOCK_RDLOCK_PREFER_WRITER
/* glibc with bug https://sourceware.org/bugzilla/show_bug.cgi?id=13701 */
int
glthread_rwlock_init_for_glibc (pthread_rwlock_t *lock)
{
pthread_rwlockattr_t attributes;
int err;
err = pthread_rwlockattr_init (&attributes);
if (err != 0)
return err;
/* Note: PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP is the only value that
causes the writer to be preferred. PTHREAD_RWLOCK_PREFER_WRITER_NP does not
do this; see
http://man7.org/linux/man-pages/man3/pthread_rwlockattr_setkind_np.3.html */
err = pthread_rwlockattr_setkind_np (&attributes,
PTHREAD_RWLOCK_PREFER_WRITER_NONRECURSIVE_NP);
if (err == 0)
err = pthread_rwlock_init(lock, &attributes);
/* pthread_rwlockattr_destroy always returns 0. It cannot influence the
return value. */
pthread_rwlockattr_destroy (&attributes);
return err;
}
# endif
# else
int
glthread_rwlock_init_multithreaded (gl_rwlock_t *lock)
@ -152,11 +403,9 @@ glthread_rwlock_rdlock_multithreaded (gl_rwlock_t *lock)
if (err != 0)
return err;
/* Test whether only readers are currently running, and whether the runcount
field will not overflow. */
/* POSIX says: "It is implementation-defined whether the calling thread
acquires the lock when a writer does not hold the lock and there are
writers blocked on the lock." Let's say, no: give the writers a higher
priority. */
field will not overflow, and whether no writer is waiting. The latter
condition is because POSIX recommends that "write locks shall take
precedence over read locks", to avoid "writer starvation". */
while (!(lock->runcount + 1 > 0 && lock->waiting_writers_count == 0))
{
/* This thread has to wait for a while. Enqueue it among the
@ -469,161 +718,25 @@ glthread_once_singlethreaded (pthread_once_t *once_control)
return 0;
}
#endif
/* ========================================================================= */
#if USE_PTH_THREADS
/* Use the GNU Pth threads library. */
/* -------------------------- gl_lock_t datatype -------------------------- */
/* ------------------------- gl_rwlock_t datatype ------------------------- */
/* --------------------- gl_recursive_lock_t datatype --------------------- */
/* -------------------------- gl_once_t datatype -------------------------- */
static void
glthread_once_call (void *arg)
{
void (**gl_once_temp_addr) (void) = (void (**) (void)) arg;
void (*initfunction) (void) = *gl_once_temp_addr;
initfunction ();
}
# if !(PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK)
int
glthread_once_multithreaded (pth_once_t *once_control, void (*initfunction) (void))
glthread_once_multithreaded (pthread_once_t *once_control,
void (*init_function) (void))
{
void (*temp) (void) = initfunction;
return (!pth_once (once_control, glthread_once_call, &temp) ? errno : 0);
}
int
glthread_once_singlethreaded (pth_once_t *once_control)
{
/* We know that pth_once_t is an integer type. */
if (*once_control == PTH_ONCE_INIT)
int err = pthread_once (once_control, init_function);
if (err == ENOSYS)
{
/* First time use of once_control. Invert the marker. */
*once_control = ~ PTH_ONCE_INIT;
return 1;
/* This happens on FreeBSD 11: The pthread_once function in libc returns
ENOSYS. */
if (glthread_once_singlethreaded (once_control))
init_function ();
return 0;
}
else
return 0;
return err;
}
#endif
/* ========================================================================= */
#if USE_SOLARIS_THREADS
/* Use the old Solaris threads library. */
/* -------------------------- gl_lock_t datatype -------------------------- */
/* ------------------------- gl_rwlock_t datatype ------------------------- */
/* --------------------- gl_recursive_lock_t datatype --------------------- */
int
glthread_recursive_lock_init_multithreaded (gl_recursive_lock_t *lock)
{
int err;
err = mutex_init (&lock->mutex, USYNC_THREAD, NULL);
if (err != 0)
return err;
lock->owner = (thread_t) 0;
lock->depth = 0;
return 0;
}
int
glthread_recursive_lock_lock_multithreaded (gl_recursive_lock_t *lock)
{
thread_t self = thr_self ();
if (lock->owner != self)
{
int err;
err = mutex_lock (&lock->mutex);
if (err != 0)
return err;
lock->owner = self;
}
if (++(lock->depth) == 0) /* wraparound? */
{
lock->depth--;
return EAGAIN;
}
return 0;
}
int
glthread_recursive_lock_unlock_multithreaded (gl_recursive_lock_t *lock)
{
if (lock->owner != thr_self ())
return EPERM;
if (lock->depth == 0)
return EINVAL;
if (--(lock->depth) == 0)
{
lock->owner = (thread_t) 0;
return mutex_unlock (&lock->mutex);
}
else
return 0;
}
int
glthread_recursive_lock_destroy_multithreaded (gl_recursive_lock_t *lock)
{
if (lock->owner != (thread_t) 0)
return EBUSY;
return mutex_destroy (&lock->mutex);
}
/* -------------------------- gl_once_t datatype -------------------------- */
int
glthread_once_multithreaded (gl_once_t *once_control, void (*initfunction) (void))
{
if (!once_control->inited)
{
int err;
/* Use the mutex to guarantee that if another thread is already calling
the initfunction, this thread waits until it's finished. */
err = mutex_lock (&once_control->mutex);
if (err != 0)
return err;
if (!once_control->inited)
{
once_control->inited = 1;
initfunction ();
}
return mutex_unlock (&once_control->mutex);
}
else
return 0;
}
int
glthread_once_singlethreaded (gl_once_t *once_control)
{
/* We know that gl_once_t contains an integer type. */
if (!once_control->inited)
{
/* First time use of once_control. Invert the marker. */
once_control->inited = ~ 0;
return 1;
}
else
return 0;
}
# endif
#endif
@ -631,427 +744,6 @@ glthread_once_singlethreaded (gl_once_t *once_control)
#if USE_WINDOWS_THREADS
/* -------------------------- gl_lock_t datatype -------------------------- */
void
glthread_lock_init_func (gl_lock_t *lock)
{
InitializeCriticalSection (&lock->lock);
lock->guard.done = 1;
}
int
glthread_lock_lock_func (gl_lock_t *lock)
{
if (!lock->guard.done)
{
if (InterlockedIncrement (&lock->guard.started) == 0)
/* This thread is the first one to need this lock. Initialize it. */
glthread_lock_init (lock);
else
/* Yield the CPU while waiting for another thread to finish
initializing this lock. */
while (!lock->guard.done)
Sleep (0);
}
EnterCriticalSection (&lock->lock);
return 0;
}
int
glthread_lock_unlock_func (gl_lock_t *lock)
{
if (!lock->guard.done)
return EINVAL;
LeaveCriticalSection (&lock->lock);
return 0;
}
int
glthread_lock_destroy_func (gl_lock_t *lock)
{
if (!lock->guard.done)
return EINVAL;
DeleteCriticalSection (&lock->lock);
lock->guard.done = 0;
return 0;
}
/* ------------------------- gl_rwlock_t datatype ------------------------- */
/* In this file, the waitqueues are implemented as circular arrays. */
#define gl_waitqueue_t gl_carray_waitqueue_t
static void
gl_waitqueue_init (gl_waitqueue_t *wq)
{
wq->array = NULL;
wq->count = 0;
wq->alloc = 0;
wq->offset = 0;
}
/* Enqueues the current thread, represented by an event, in a wait queue.
Returns INVALID_HANDLE_VALUE if an allocation failure occurs. */
static HANDLE
gl_waitqueue_add (gl_waitqueue_t *wq)
{
HANDLE event;
unsigned int index;
if (wq->count == wq->alloc)
{
unsigned int new_alloc = 2 * wq->alloc + 1;
HANDLE *new_array =
(HANDLE *) realloc (wq->array, new_alloc * sizeof (HANDLE));
if (new_array == NULL)
/* No more memory. */
return INVALID_HANDLE_VALUE;
/* Now is a good opportunity to rotate the array so that its contents
starts at offset 0. */
if (wq->offset > 0)
{
unsigned int old_count = wq->count;
unsigned int old_alloc = wq->alloc;
unsigned int old_offset = wq->offset;
unsigned int i;
if (old_offset + old_count > old_alloc)
{
unsigned int limit = old_offset + old_count - old_alloc;
for (i = 0; i < limit; i++)
new_array[old_alloc + i] = new_array[i];
}
for (i = 0; i < old_count; i++)
new_array[i] = new_array[old_offset + i];
wq->offset = 0;
}
wq->array = new_array;
wq->alloc = new_alloc;
}
/* Whether the created event is a manual-reset one or an auto-reset one,
does not matter, since we will wait on it only once. */
event = CreateEvent (NULL, TRUE, FALSE, NULL);
if (event == INVALID_HANDLE_VALUE)
/* No way to allocate an event. */
return INVALID_HANDLE_VALUE;
index = wq->offset + wq->count;
if (index >= wq->alloc)
index -= wq->alloc;
wq->array[index] = event;
wq->count++;
return event;
}
/* Notifies the first thread from a wait queue and dequeues it. */
static void
gl_waitqueue_notify_first (gl_waitqueue_t *wq)
{
SetEvent (wq->array[wq->offset + 0]);
wq->offset++;
wq->count--;
if (wq->count == 0 || wq->offset == wq->alloc)
wq->offset = 0;
}
/* Notifies all threads from a wait queue and dequeues them all. */
static void
gl_waitqueue_notify_all (gl_waitqueue_t *wq)
{
unsigned int i;
for (i = 0; i < wq->count; i++)
{
unsigned int index = wq->offset + i;
if (index >= wq->alloc)
index -= wq->alloc;
SetEvent (wq->array[index]);
}
wq->count = 0;
wq->offset = 0;
}
void
glthread_rwlock_init_func (gl_rwlock_t *lock)
{
InitializeCriticalSection (&lock->lock);
gl_waitqueue_init (&lock->waiting_readers);
gl_waitqueue_init (&lock->waiting_writers);
lock->runcount = 0;
lock->guard.done = 1;
}
int
glthread_rwlock_rdlock_func (gl_rwlock_t *lock)
{
if (!lock->guard.done)
{
if (InterlockedIncrement (&lock->guard.started) == 0)
/* This thread is the first one to need this lock. Initialize it. */
glthread_rwlock_init (lock);
else
/* Yield the CPU while waiting for another thread to finish
initializing this lock. */
while (!lock->guard.done)
Sleep (0);
}
EnterCriticalSection (&lock->lock);
/* Test whether only readers are currently running, and whether the runcount
field will not overflow. */
if (!(lock->runcount + 1 > 0))
{
/* This thread has to wait for a while. Enqueue it among the
waiting_readers. */
HANDLE event = gl_waitqueue_add (&lock->waiting_readers);
if (event != INVALID_HANDLE_VALUE)
{
DWORD result;
LeaveCriticalSection (&lock->lock);
/* Wait until another thread signals this event. */
result = WaitForSingleObject (event, INFINITE);
if (result == WAIT_FAILED || result == WAIT_TIMEOUT)
abort ();
CloseHandle (event);
/* The thread which signalled the event already did the bookkeeping:
removed us from the waiting_readers, incremented lock->runcount. */
if (!(lock->runcount > 0))
abort ();
return 0;
}
else
{
/* Allocation failure. Weird. */
do
{
LeaveCriticalSection (&lock->lock);
Sleep (1);
EnterCriticalSection (&lock->lock);
}
while (!(lock->runcount + 1 > 0));
}
}
lock->runcount++;
LeaveCriticalSection (&lock->lock);
return 0;
}
int
glthread_rwlock_wrlock_func (gl_rwlock_t *lock)
{
if (!lock->guard.done)
{
if (InterlockedIncrement (&lock->guard.started) == 0)
/* This thread is the first one to need this lock. Initialize it. */
glthread_rwlock_init (lock);
else
/* Yield the CPU while waiting for another thread to finish
initializing this lock. */
while (!lock->guard.done)
Sleep (0);
}
EnterCriticalSection (&lock->lock);
/* Test whether no readers or writers are currently running. */
if (!(lock->runcount == 0))
{
/* This thread has to wait for a while. Enqueue it among the
waiting_writers. */
HANDLE event = gl_waitqueue_add (&lock->waiting_writers);
if (event != INVALID_HANDLE_VALUE)
{
DWORD result;
LeaveCriticalSection (&lock->lock);
/* Wait until another thread signals this event. */
result = WaitForSingleObject (event, INFINITE);
if (result == WAIT_FAILED || result == WAIT_TIMEOUT)
abort ();
CloseHandle (event);
/* The thread which signalled the event already did the bookkeeping:
removed us from the waiting_writers, set lock->runcount = -1. */
if (!(lock->runcount == -1))
abort ();
return 0;
}
else
{
/* Allocation failure. Weird. */
do
{
LeaveCriticalSection (&lock->lock);
Sleep (1);
EnterCriticalSection (&lock->lock);
}
while (!(lock->runcount == 0));
}
}
lock->runcount--; /* runcount becomes -1 */
LeaveCriticalSection (&lock->lock);
return 0;
}
int
glthread_rwlock_unlock_func (gl_rwlock_t *lock)
{
if (!lock->guard.done)
return EINVAL;
EnterCriticalSection (&lock->lock);
if (lock->runcount < 0)
{
/* Drop a writer lock. */
if (!(lock->runcount == -1))
abort ();
lock->runcount = 0;
}
else
{
/* Drop a reader lock. */
if (!(lock->runcount > 0))
{
LeaveCriticalSection (&lock->lock);
return EPERM;
}
lock->runcount--;
}
if (lock->runcount == 0)
{
/* POSIX recommends that "write locks shall take precedence over read
locks", to avoid "writer starvation". */
if (lock->waiting_writers.count > 0)
{
/* Wake up one of the waiting writers. */
lock->runcount--;
gl_waitqueue_notify_first (&lock->waiting_writers);
}
else
{
/* Wake up all waiting readers. */
lock->runcount += lock->waiting_readers.count;
gl_waitqueue_notify_all (&lock->waiting_readers);
}
}
LeaveCriticalSection (&lock->lock);
return 0;
}
int
glthread_rwlock_destroy_func (gl_rwlock_t *lock)
{
if (!lock->guard.done)
return EINVAL;
if (lock->runcount != 0)
return EBUSY;
DeleteCriticalSection (&lock->lock);
if (lock->waiting_readers.array != NULL)
free (lock->waiting_readers.array);
if (lock->waiting_writers.array != NULL)
free (lock->waiting_writers.array);
lock->guard.done = 0;
return 0;
}
/* --------------------- gl_recursive_lock_t datatype --------------------- */
void
glthread_recursive_lock_init_func (gl_recursive_lock_t *lock)
{
lock->owner = 0;
lock->depth = 0;
InitializeCriticalSection (&lock->lock);
lock->guard.done = 1;
}
int
glthread_recursive_lock_lock_func (gl_recursive_lock_t *lock)
{
if (!lock->guard.done)
{
if (InterlockedIncrement (&lock->guard.started) == 0)
/* This thread is the first one to need this lock. Initialize it. */
glthread_recursive_lock_init (lock);
else
/* Yield the CPU while waiting for another thread to finish
initializing this lock. */
while (!lock->guard.done)
Sleep (0);
}
{
DWORD self = GetCurrentThreadId ();
if (lock->owner != self)
{
EnterCriticalSection (&lock->lock);
lock->owner = self;
}
if (++(lock->depth) == 0) /* wraparound? */
{
lock->depth--;
return EAGAIN;
}
}
return 0;
}
int
glthread_recursive_lock_unlock_func (gl_recursive_lock_t *lock)
{
if (lock->owner != GetCurrentThreadId ())
return EPERM;
if (lock->depth == 0)
return EINVAL;
if (--(lock->depth) == 0)
{
lock->owner = 0;
LeaveCriticalSection (&lock->lock);
}
return 0;
}
int
glthread_recursive_lock_destroy_func (gl_recursive_lock_t *lock)
{
if (lock->owner != 0)
return EBUSY;
DeleteCriticalSection (&lock->lock);
lock->guard.done = 0;
return 0;
}
/* -------------------------- gl_once_t datatype -------------------------- */
void
glthread_once_func (gl_once_t *once_control, void (*initfunction) (void))
{
if (once_control->inited <= 0)
{
if (InterlockedIncrement (&once_control->started) == 0)
{
/* This thread is the first one to come to this once_control. */
InitializeCriticalSection (&once_control->lock);
EnterCriticalSection (&once_control->lock);
once_control->inited = 0;
initfunction ();
once_control->inited = 1;
LeaveCriticalSection (&once_control->lock);
}
else
{
/* Undo last operation. */
InterlockedDecrement (&once_control->started);
/* Some other thread has already started the initialization.
Yield the CPU while waiting for the other thread to finish
initializing and taking the lock. */
while (once_control->inited < 0)
Sleep (0);
if (once_control->inited <= 0)
{
/* Take the lock. This blocks until the other thread has
finished calling the initfunction. */
EnterCriticalSection (&once_control->lock);
LeaveCriticalSection (&once_control->lock);
if (!(once_control->inited > 0))
abort ();
}
}
}
}
#endif
/* ========================================================================= */

546
gl/glthread/lock.h
View file

@ -1,22 +1,21 @@
/* Locking in multithreaded situations.
Copyright (C) 2005-2013 Free Software Foundation, Inc.
Copyright (C) 2005-2023 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
GNU Lesser General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>. */
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2005.
Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-solaris.h,
gthr-win32.h. */
Based on GCC's gthr-posix.h, gthr-posix95.h, gthr-win32.h. */
/* This file contains locking primitives for use with a given thread library.
It does not contain primitives for creating threads or for other
@ -81,6 +80,127 @@
#include <errno.h>
#include <stdlib.h>
#if !defined c11_threads_in_use
# if HAVE_THREADS_H && USE_POSIX_THREADS_FROM_LIBC
# define c11_threads_in_use() 1
# elif HAVE_THREADS_H && USE_POSIX_THREADS_WEAK
# include <threads.h>
# pragma weak thrd_exit
# define c11_threads_in_use() (thrd_exit != NULL)
# else
# define c11_threads_in_use() 0
# endif
#endif
/* ========================================================================= */
#if USE_ISOC_THREADS || USE_ISOC_AND_POSIX_THREADS
/* Use the ISO C threads library. */
# include <threads.h>
# ifdef __cplusplus
extern "C" {
# endif
/* -------------------------- gl_lock_t datatype -------------------------- */
typedef struct
{
int volatile init_needed;
once_flag init_once;
void (*init_func) (void);
mtx_t mutex;
}
gl_lock_t;
# define gl_lock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_lock_t NAME;
# define gl_lock_define_initialized(STORAGECLASS, NAME) \
static void _atomic_init_##NAME (void); \
STORAGECLASS gl_lock_t NAME = \
{ 1, ONCE_FLAG_INIT, _atomic_init_##NAME }; \
static void _atomic_init_##NAME (void) \
{ \
if (glthread_lock_init (&(NAME))) \
abort (); \
}
extern int glthread_lock_init (gl_lock_t *lock);
extern int glthread_lock_lock (gl_lock_t *lock);
extern int glthread_lock_unlock (gl_lock_t *lock);
extern int glthread_lock_destroy (gl_lock_t *lock);
/* ------------------------- gl_rwlock_t datatype ------------------------- */
typedef struct
{
int volatile init_needed;
once_flag init_once;
void (*init_func) (void);
mtx_t lock; /* protects the remaining fields */
cnd_t waiting_readers; /* waiting readers */
cnd_t waiting_writers; /* waiting writers */
unsigned int waiting_writers_count; /* number of waiting writers */
int runcount; /* number of readers running, or -1 when a writer runs */
}
gl_rwlock_t;
# define gl_rwlock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_rwlock_t NAME;
# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
static void _atomic_init_##NAME (void); \
STORAGECLASS gl_rwlock_t NAME = \
{ 1, ONCE_FLAG_INIT, _atomic_init_##NAME }; \
static void _atomic_init_##NAME (void) \
{ \
if (glthread_rwlock_init (&(NAME))) \
abort (); \
}
extern int glthread_rwlock_init (gl_rwlock_t *lock);
extern int glthread_rwlock_rdlock (gl_rwlock_t *lock);
extern int glthread_rwlock_wrlock (gl_rwlock_t *lock);
extern int glthread_rwlock_unlock (gl_rwlock_t *lock);
extern int glthread_rwlock_destroy (gl_rwlock_t *lock);
/* --------------------- gl_recursive_lock_t datatype --------------------- */
typedef struct
{
int volatile init_needed;
once_flag init_once;
void (*init_func) (void);
mtx_t mutex;
}
gl_recursive_lock_t;
# define gl_recursive_lock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_recursive_lock_t NAME;
# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
static void _atomic_init_##NAME (void); \
STORAGECLASS gl_recursive_lock_t NAME = \
{ 1, ONCE_FLAG_INIT, _atomic_init_##NAME }; \
static void _atomic_init_##NAME (void) \
{ \
if (glthread_recursive_lock_init (&(NAME))) \
abort (); \
}
extern int glthread_recursive_lock_init (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_lock (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_unlock (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_destroy (gl_recursive_lock_t *lock);
/* -------------------------- gl_once_t datatype -------------------------- */
typedef once_flag gl_once_t;
# define gl_once_define(STORAGECLASS, NAME) \
STORAGECLASS once_flag NAME = ONCE_FLAG_INIT;
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(call_once (ONCE_CONTROL, INITFUNCTION), 0)
# ifdef __cplusplus
}
# endif
#endif
/* ========================================================================= */
#if USE_POSIX_THREADS
@ -139,13 +259,25 @@ extern int glthread_in_use (void);
# pragma weak pthread_mutexattr_init
# pragma weak pthread_mutexattr_settype
# pragma weak pthread_mutexattr_destroy
# pragma weak pthread_rwlockattr_init
# if __GNU_LIBRARY__ > 1
# pragma weak pthread_rwlockattr_setkind_np
# endif
# pragma weak pthread_rwlockattr_destroy
# ifndef pthread_self
# pragma weak pthread_self
# endif
# if !PTHREAD_IN_USE_DETECTION_HARD
# pragma weak pthread_cancel
# define pthread_in_use() (pthread_cancel != NULL)
/* Considering all platforms with USE_POSIX_THREADS_WEAK, only few symbols
can be used to determine whether libpthread is in use. These are:
pthread_mutexattr_gettype
pthread_rwlockattr_destroy
pthread_rwlockattr_init
*/
# pragma weak pthread_mutexattr_gettype
# define pthread_in_use() \
(pthread_mutexattr_gettype != NULL || c11_threads_in_use ())
# endif
# else
@ -176,19 +308,32 @@ typedef pthread_mutex_t gl_lock_t;
/* ------------------------- gl_rwlock_t datatype ------------------------- */
# if HAVE_PTHREAD_RWLOCK
# if HAVE_PTHREAD_RWLOCK && (HAVE_PTHREAD_RWLOCK_RDLOCK_PREFER_WRITER || (defined PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP && (__GNU_LIBRARY__ > 1)))
# ifdef PTHREAD_RWLOCK_INITIALIZER
# if defined PTHREAD_RWLOCK_INITIALIZER || defined PTHREAD_RWLOCK_INITIALIZER_NP
typedef pthread_rwlock_t gl_rwlock_t;
# define gl_rwlock_define(STORAGECLASS, NAME) \
STORAGECLASS pthread_rwlock_t NAME;
# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS pthread_rwlock_t NAME = gl_rwlock_initializer;
# define gl_rwlock_initializer \
PTHREAD_RWLOCK_INITIALIZER
# define glthread_rwlock_init(LOCK) \
(pthread_in_use () ? pthread_rwlock_init (LOCK, NULL) : 0)
# if HAVE_PTHREAD_RWLOCK_RDLOCK_PREFER_WRITER
# if defined PTHREAD_RWLOCK_INITIALIZER
# define gl_rwlock_initializer \
PTHREAD_RWLOCK_INITIALIZER
# else
# define gl_rwlock_initializer \
PTHREAD_RWLOCK_INITIALIZER_NP
# endif
# define glthread_rwlock_init(LOCK) \
(pthread_in_use () ? pthread_rwlock_init (LOCK, NULL) : 0)
# else /* glibc with bug https://sourceware.org/bugzilla/show_bug.cgi?id=13701 */
# define gl_rwlock_initializer \
PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP
# define glthread_rwlock_init(LOCK) \
(pthread_in_use () ? glthread_rwlock_init_for_glibc (LOCK) : 0)
extern int glthread_rwlock_init_for_glibc (pthread_rwlock_t *lock);
# endif
# define glthread_rwlock_rdlock(LOCK) \
(pthread_in_use () ? pthread_rwlock_rdlock (LOCK) : 0)
# define glthread_rwlock_wrlock(LOCK) \
@ -362,10 +507,19 @@ extern int glthread_recursive_lock_destroy_multithreaded (gl_recursive_lock_t *l
typedef pthread_once_t gl_once_t;
# define gl_once_define(STORAGECLASS, NAME) \
STORAGECLASS pthread_once_t NAME = PTHREAD_ONCE_INIT;
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(pthread_in_use () \
? pthread_once (ONCE_CONTROL, INITFUNCTION) \
: (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
# if PTHREAD_IN_USE_DETECTION_HARD || USE_POSIX_THREADS_WEAK
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(pthread_in_use () \
? pthread_once (ONCE_CONTROL, INITFUNCTION) \
: (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
# else
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(pthread_in_use () \
? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION) \
: (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
extern int glthread_once_multithreaded (pthread_once_t *once_control,
void (*init_function) (void));
# endif
extern int glthread_once_singlethreaded (pthread_once_t *once_control);
# ifdef __cplusplus
@ -376,248 +530,16 @@ extern int glthread_once_singlethreaded (pthread_once_t *once_control);
/* ========================================================================= */
#if USE_PTH_THREADS
/* Use the GNU Pth threads library. */
# include <pth.h>
# ifdef __cplusplus
extern "C" {
# endif
# if USE_PTH_THREADS_WEAK
/* Use weak references to the GNU Pth threads library. */
# pragma weak pth_mutex_init
# pragma weak pth_mutex_acquire
# pragma weak pth_mutex_release
# pragma weak pth_rwlock_init
# pragma weak pth_rwlock_acquire
# pragma weak pth_rwlock_release
# pragma weak pth_once
# pragma weak pth_cancel
# define pth_in_use() (pth_cancel != NULL)
# else
# define pth_in_use() 1
# endif
/* -------------------------- gl_lock_t datatype -------------------------- */
typedef pth_mutex_t gl_lock_t;
# define gl_lock_define(STORAGECLASS, NAME) \
STORAGECLASS pth_mutex_t NAME;
# define gl_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS pth_mutex_t NAME = gl_lock_initializer;
# define gl_lock_initializer \
PTH_MUTEX_INIT
# define glthread_lock_init(LOCK) \
(pth_in_use () && !pth_mutex_init (LOCK) ? errno : 0)
# define glthread_lock_lock(LOCK) \
(pth_in_use () && !pth_mutex_acquire (LOCK, 0, NULL) ? errno : 0)
# define glthread_lock_unlock(LOCK) \
(pth_in_use () && !pth_mutex_release (LOCK) ? errno : 0)
# define glthread_lock_destroy(LOCK) \
((void)(LOCK), 0)
/* ------------------------- gl_rwlock_t datatype ------------------------- */
typedef pth_rwlock_t gl_rwlock_t;
# define gl_rwlock_define(STORAGECLASS, NAME) \
STORAGECLASS pth_rwlock_t NAME;
# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS pth_rwlock_t NAME = gl_rwlock_initializer;
# define gl_rwlock_initializer \
PTH_RWLOCK_INIT
# define glthread_rwlock_init(LOCK) \
(pth_in_use () && !pth_rwlock_init (LOCK) ? errno : 0)
# define glthread_rwlock_rdlock(LOCK) \
(pth_in_use () && !pth_rwlock_acquire (LOCK, PTH_RWLOCK_RD, 0, NULL) ? errno : 0)
# define glthread_rwlock_wrlock(LOCK) \
(pth_in_use () && !pth_rwlock_acquire (LOCK, PTH_RWLOCK_RW, 0, NULL) ? errno : 0)
# define glthread_rwlock_unlock(LOCK) \
(pth_in_use () && !pth_rwlock_release (LOCK) ? errno : 0)
# define glthread_rwlock_destroy(LOCK) \
((void)(LOCK), 0)
/* --------------------- gl_recursive_lock_t datatype --------------------- */
/* In Pth, mutexes are recursive by default. */
typedef pth_mutex_t gl_recursive_lock_t;
# define gl_recursive_lock_define(STORAGECLASS, NAME) \
STORAGECLASS pth_mutex_t NAME;
# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS pth_mutex_t NAME = gl_recursive_lock_initializer;
# define gl_recursive_lock_initializer \
PTH_MUTEX_INIT
# define glthread_recursive_lock_init(LOCK) \
(pth_in_use () && !pth_mutex_init (LOCK) ? errno : 0)
# define glthread_recursive_lock_lock(LOCK) \
(pth_in_use () && !pth_mutex_acquire (LOCK, 0, NULL) ? errno : 0)
# define glthread_recursive_lock_unlock(LOCK) \
(pth_in_use () && !pth_mutex_release (LOCK) ? errno : 0)
# define glthread_recursive_lock_destroy(LOCK) \
((void)(LOCK), 0)
/* -------------------------- gl_once_t datatype -------------------------- */
typedef pth_once_t gl_once_t;
# define gl_once_define(STORAGECLASS, NAME) \
STORAGECLASS pth_once_t NAME = PTH_ONCE_INIT;
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(pth_in_use () \
? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION) \
: (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
extern int glthread_once_multithreaded (pth_once_t *once_control, void (*initfunction) (void));
extern int glthread_once_singlethreaded (pth_once_t *once_control);
# ifdef __cplusplus
}
# endif
#endif
/* ========================================================================= */
#if USE_SOLARIS_THREADS
/* Use the old Solaris threads library. */
# include <thread.h>
# include <synch.h>
# ifdef __cplusplus
extern "C" {
# endif
# if USE_SOLARIS_THREADS_WEAK
/* Use weak references to the old Solaris threads library. */
# pragma weak mutex_init
# pragma weak mutex_lock
# pragma weak mutex_unlock
# pragma weak mutex_destroy
# pragma weak rwlock_init
# pragma weak rw_rdlock
# pragma weak rw_wrlock
# pragma weak rw_unlock
# pragma weak rwlock_destroy
# pragma weak thr_self
# pragma weak thr_suspend
# define thread_in_use() (thr_suspend != NULL)
# else
# define thread_in_use() 1
# endif
/* -------------------------- gl_lock_t datatype -------------------------- */
typedef mutex_t gl_lock_t;
# define gl_lock_define(STORAGECLASS, NAME) \
STORAGECLASS mutex_t NAME;
# define gl_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS mutex_t NAME = gl_lock_initializer;
# define gl_lock_initializer \
DEFAULTMUTEX
# define glthread_lock_init(LOCK) \
(thread_in_use () ? mutex_init (LOCK, USYNC_THREAD, NULL) : 0)
# define glthread_lock_lock(LOCK) \
(thread_in_use () ? mutex_lock (LOCK) : 0)
# define glthread_lock_unlock(LOCK) \
(thread_in_use () ? mutex_unlock (LOCK) : 0)
# define glthread_lock_destroy(LOCK) \
(thread_in_use () ? mutex_destroy (LOCK) : 0)
/* ------------------------- gl_rwlock_t datatype ------------------------- */
typedef rwlock_t gl_rwlock_t;
# define gl_rwlock_define(STORAGECLASS, NAME) \
STORAGECLASS rwlock_t NAME;
# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS rwlock_t NAME = gl_rwlock_initializer;
# define gl_rwlock_initializer \
DEFAULTRWLOCK
# define glthread_rwlock_init(LOCK) \
(thread_in_use () ? rwlock_init (LOCK, USYNC_THREAD, NULL) : 0)
# define glthread_rwlock_rdlock(LOCK) \
(thread_in_use () ? rw_rdlock (LOCK) : 0)
# define glthread_rwlock_wrlock(LOCK) \
(thread_in_use () ? rw_wrlock (LOCK) : 0)
# define glthread_rwlock_unlock(LOCK) \
(thread_in_use () ? rw_unlock (LOCK) : 0)
# define glthread_rwlock_destroy(LOCK) \
(thread_in_use () ? rwlock_destroy (LOCK) : 0)
/* --------------------- gl_recursive_lock_t datatype --------------------- */
/* Old Solaris threads did not have recursive locks.
We have to implement them ourselves. */
typedef struct
{
mutex_t mutex;
thread_t owner;
unsigned long depth;
}
gl_recursive_lock_t;
# define gl_recursive_lock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_recursive_lock_t NAME;
# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
# define gl_recursive_lock_initializer \
{ DEFAULTMUTEX, (thread_t) 0, 0 }
# define glthread_recursive_lock_init(LOCK) \
(thread_in_use () ? glthread_recursive_lock_init_multithreaded (LOCK) : 0)
# define glthread_recursive_lock_lock(LOCK) \
(thread_in_use () ? glthread_recursive_lock_lock_multithreaded (LOCK) : 0)
# define glthread_recursive_lock_unlock(LOCK) \
(thread_in_use () ? glthread_recursive_lock_unlock_multithreaded (LOCK) : 0)
# define glthread_recursive_lock_destroy(LOCK) \
(thread_in_use () ? glthread_recursive_lock_destroy_multithreaded (LOCK) : 0)
extern int glthread_recursive_lock_init_multithreaded (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_lock_multithreaded (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_unlock_multithreaded (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_destroy_multithreaded (gl_recursive_lock_t *lock);
/* -------------------------- gl_once_t datatype -------------------------- */
typedef struct
{
volatile int inited;
mutex_t mutex;
}
gl_once_t;
# define gl_once_define(STORAGECLASS, NAME) \
STORAGECLASS gl_once_t NAME = { 0, DEFAULTMUTEX };
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(thread_in_use () \
? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION) \
: (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
extern int glthread_once_multithreaded (gl_once_t *once_control, void (*initfunction) (void));
extern int glthread_once_singlethreaded (gl_once_t *once_control);
# ifdef __cplusplus
}
# endif
#endif
/* ========================================================================= */
#if USE_WINDOWS_THREADS
# define WIN32_LEAN_AND_MEAN /* avoid including junk */
# include <windows.h>
# include "windows-mutex.h"
# include "windows-rwlock.h"
# include "windows-recmutex.h"
# include "windows-once.h"
# ifdef __cplusplus
extern "C" {
# endif
@ -633,127 +555,69 @@ extern "C" {
/* There is no way to statically initialize a CRITICAL_SECTION. It needs
to be done lazily, once only. For this we need spinlocks. */
typedef struct { volatile int done; volatile long started; } gl_spinlock_t;
/* -------------------------- gl_lock_t datatype -------------------------- */
typedef struct
{
gl_spinlock_t guard; /* protects the initialization */
CRITICAL_SECTION lock;
}
gl_lock_t;
typedef glwthread_mutex_t gl_lock_t;
# define gl_lock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_lock_t NAME;
# define gl_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS gl_lock_t NAME = gl_lock_initializer;
# define gl_lock_initializer \
{ { 0, -1 } }
GLWTHREAD_MUTEX_INIT
# define glthread_lock_init(LOCK) \
(glthread_lock_init_func (LOCK), 0)
(glwthread_mutex_init (LOCK), 0)
# define glthread_lock_lock(LOCK) \
glthread_lock_lock_func (LOCK)
glwthread_mutex_lock (LOCK)
# define glthread_lock_unlock(LOCK) \
glthread_lock_unlock_func (LOCK)
glwthread_mutex_unlock (LOCK)
# define glthread_lock_destroy(LOCK) \
glthread_lock_destroy_func (LOCK)
extern void glthread_lock_init_func (gl_lock_t *lock);
extern int glthread_lock_lock_func (gl_lock_t *lock);
extern int glthread_lock_unlock_func (gl_lock_t *lock);
extern int glthread_lock_destroy_func (gl_lock_t *lock);
glwthread_mutex_destroy (LOCK)
/* ------------------------- gl_rwlock_t datatype ------------------------- */
/* It is impossible to implement read-write locks using plain locks, without
introducing an extra thread dedicated to managing read-write locks.
Therefore here we need to use the low-level Event type. */
typedef struct
{
HANDLE *array; /* array of waiting threads, each represented by an event */
unsigned int count; /* number of waiting threads */
unsigned int alloc; /* length of allocated array */
unsigned int offset; /* index of first waiting thread in array */
}
gl_carray_waitqueue_t;
typedef struct
{
gl_spinlock_t guard; /* protects the initialization */
CRITICAL_SECTION lock; /* protects the remaining fields */
gl_carray_waitqueue_t waiting_readers; /* waiting readers */
gl_carray_waitqueue_t waiting_writers; /* waiting writers */
int runcount; /* number of readers running, or -1 when a writer runs */
}
gl_rwlock_t;
typedef glwthread_rwlock_t gl_rwlock_t;
# define gl_rwlock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_rwlock_t NAME;
# define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS gl_rwlock_t NAME = gl_rwlock_initializer;
# define gl_rwlock_initializer \
{ { 0, -1 } }
GLWTHREAD_RWLOCK_INIT
# define glthread_rwlock_init(LOCK) \
(glthread_rwlock_init_func (LOCK), 0)
(glwthread_rwlock_init (LOCK), 0)
# define glthread_rwlock_rdlock(LOCK) \
glthread_rwlock_rdlock_func (LOCK)
glwthread_rwlock_rdlock (LOCK)
# define glthread_rwlock_wrlock(LOCK) \
glthread_rwlock_wrlock_func (LOCK)
glwthread_rwlock_wrlock (LOCK)
# define glthread_rwlock_unlock(LOCK) \
glthread_rwlock_unlock_func (LOCK)
glwthread_rwlock_unlock (LOCK)
# define glthread_rwlock_destroy(LOCK) \
glthread_rwlock_destroy_func (LOCK)
extern void glthread_rwlock_init_func (gl_rwlock_t *lock);
extern int glthread_rwlock_rdlock_func (gl_rwlock_t *lock);
extern int glthread_rwlock_wrlock_func (gl_rwlock_t *lock);
extern int glthread_rwlock_unlock_func (gl_rwlock_t *lock);
extern int glthread_rwlock_destroy_func (gl_rwlock_t *lock);
glwthread_rwlock_destroy (LOCK)
/* --------------------- gl_recursive_lock_t datatype --------------------- */
/* The native Windows documentation says that CRITICAL_SECTION already
implements a recursive lock. But we need not rely on it: It's easy to
implement a recursive lock without this assumption. */
typedef struct
{
gl_spinlock_t guard; /* protects the initialization */
DWORD owner;
unsigned long depth;
CRITICAL_SECTION lock;
}
gl_recursive_lock_t;
typedef glwthread_recmutex_t gl_recursive_lock_t;
# define gl_recursive_lock_define(STORAGECLASS, NAME) \
STORAGECLASS gl_recursive_lock_t NAME;
# define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
STORAGECLASS gl_recursive_lock_t NAME = gl_recursive_lock_initializer;
# define gl_recursive_lock_initializer \
{ { 0, -1 }, 0, 0 }
GLWTHREAD_RECMUTEX_INIT
# define glthread_recursive_lock_init(LOCK) \
(glthread_recursive_lock_init_func (LOCK), 0)
(glwthread_recmutex_init (LOCK), 0)
# define glthread_recursive_lock_lock(LOCK) \
glthread_recursive_lock_lock_func (LOCK)
glwthread_recmutex_lock (LOCK)
# define glthread_recursive_lock_unlock(LOCK) \
glthread_recursive_lock_unlock_func (LOCK)
glwthread_recmutex_unlock (LOCK)
# define glthread_recursive_lock_destroy(LOCK) \
glthread_recursive_lock_destroy_func (LOCK)
extern void glthread_recursive_lock_init_func (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_lock_func (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_unlock_func (gl_recursive_lock_t *lock);
extern int glthread_recursive_lock_destroy_func (gl_recursive_lock_t *lock);
glwthread_recmutex_destroy (LOCK)
/* -------------------------- gl_once_t datatype -------------------------- */
typedef struct
{
volatile int inited;
volatile long started;
CRITICAL_SECTION lock;
}
gl_once_t;
typedef glwthread_once_t gl_once_t;
# define gl_once_define(STORAGECLASS, NAME) \
STORAGECLASS gl_once_t NAME = { -1, -1 };
STORAGECLASS gl_once_t NAME = GLWTHREAD_ONCE_INIT;
# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
(glthread_once_func (ONCE_CONTROL, INITFUNCTION), 0)
extern void glthread_once_func (gl_once_t *once_control, void (*initfunction) (void));
(glwthread_once (ONCE_CONTROL, INITFUNCTION), 0)
# ifdef __cplusplus
}
@ -763,7 +627,7 @@ extern void glthread_once_func (gl_once_t *once_control, void (*initfunction) (v
/* ========================================================================= */
#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_SOLARIS_THREADS || USE_WINDOWS_THREADS)
#if !(USE_ISOC_THREADS || USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS || USE_WINDOWS_THREADS)
/* Provide dummy implementation if threads are not supported. */

55
gl/glthread/threadlib.c
View file

@ -1,18 +1,18 @@
/* Multithreading primitives.
Copyright (C) 2005-2013 Free Software Foundation, Inc.
Copyright (C) 2005-2023 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
GNU Lesser General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>. */
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>, 2005. */
@ -20,15 +20,48 @@
/* ========================================================================= */
#if USE_POSIX_THREADS
#if USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS
/* Use the POSIX threads library. */
# include <errno.h>
# include <pthread.h>
# include <stdlib.h>
# if PTHREAD_IN_USE_DETECTION_HARD
# if defined __FreeBSD__ || defined __DragonFly__ /* FreeBSD */
/* Test using pthread_key_create. */
int
glthread_in_use (void)
{
static int tested;
static int result; /* 1: linked with -lpthread, 0: only with libc */
if (!tested)
{
pthread_key_t key;
int err = pthread_key_create (&key, NULL);
if (err == ENOSYS)
result = 0;
else
{
result = 1;
if (err == 0)
pthread_key_delete (key);
}
tested = 1;
}
return result;
}
# else /* Solaris, HP-UX */
/* Test using pthread_create. */
/* The function to be executed by a dummy thread. */
static void *
dummy_thread_func (void *arg)
@ -62,6 +95,8 @@ glthread_in_use (void)
return result;
}
# endif
# endif
#endif