--- /dev/null
+/* Copyright (C) 2016 Free Software Foundation, Inc.
+ Contributed by Agustina Arzille <avarzille@riseup.net>, 2016.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License
+ as published by the Free Software Foundation; either
+ version 2 of the license, or (at your option) any later version.
+
+ This program 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 Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this program; if not, see
+ <http://www.gnu.org/licenses/>.
+*/
+
+#include <pthread.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <pt-internal.h>
+#include <hurdlock.h>
+
+static const pthread_mutexattr_t dfl_attr =
+{
+ .__prioceiling = 0,
+ .__protocol = PTHREAD_PRIO_NONE,
+ .__pshared = PTHREAD_PROCESS_PRIVATE,
+ .__mutex_type = __PTHREAD_MUTEX_TIMED
+};
+
+int pthread_mutexattr_init (pthread_mutexattr_t *attrp)
+{
+ *attrp = dfl_attr;
+ return (0);
+}
+
+int pthread_mutexattr_destroy (pthread_mutexattr_t *attrp)
+{
+ (void)attrp;
+ return (0);
+}
+
+int pthread_mutexattr_settype (pthread_mutexattr_t *attrp, int type)
+{
+ if (type < 0 || type > __PTHREAD_MUTEX_RECURSIVE)
+ return (EINVAL);
+
+ attrp->__mutex_type = type;
+ return (0);
+}
+
+int pthread_mutexattr_gettype (const pthread_mutexattr_t *attrp, int *outp)
+{
+ *outp = attrp->__mutex_type;
+ return (0);
+}
+
+int pthread_mutexattr_setpshared (pthread_mutexattr_t *attrp, int pshared)
+{
+ if (pshared != PTHREAD_PROCESS_PRIVATE &&
+ pshared != PTHREAD_PROCESS_SHARED)
+ return (EINVAL);
+
+ attrp->__pshared = pshared;
+ return (0);
+}
+
+int pthread_mutexattr_getpshared (const pthread_mutexattr_t *attrp, int *outp)
+{
+ *outp = attrp->__pshared;
+ return (0);
+}
+
+int pthread_mutexattr_setrobust (pthread_mutexattr_t *attrp, int robust)
+{
+ if (robust != PTHREAD_MUTEX_ROBUST &&
+ robust != PTHREAD_MUTEX_STALLED)
+ return (EINVAL);
+
+ attrp->__prioceiling |= robust;
+ return (0);
+}
+
+weak_alias (pthread_mutexattr_setrobust, pthread_mutexattr_setrobust_np)
+
+int pthread_mutexattr_getrobust (const pthread_mutexattr_t *attrp, int *outp)
+{
+ *outp = (attrp->__prioceiling & PTHREAD_MUTEX_ROBUST) ?
+ PTHREAD_MUTEX_ROBUST : PTHREAD_MUTEX_STALLED;
+ return (0);
+}
+
+weak_alias (pthread_mutexattr_getrobust, pthread_mutexattr_getrobust_np)
+
+int pthread_mutexattr_setprioceiling (pthread_mutexattr_t *attrp, int cl)
+{
+ (void)attrp; (void)cl;
+ return (ENOSYS);
+}
+
+stub_warning (pthread_mutexattr_setprioceiling)
+
+int pthread_mutexattr_getprioceiling (const pthread_mutexattr_t *ap, int *clp)
+{
+ (void)ap; (void)clp;
+ return (ENOSYS);
+}
+
+stub_warning (pthread_mutexattr_getprioceiling)
+
+int pthread_mutexattr_setprotocol (pthread_mutexattr_t *attrp, int proto)
+{
+ (void)attrp;
+ return (proto == PTHREAD_PRIO_NONE ? 0 :
+ proto != PTHREAD_PRIO_INHERIT &&
+ proto != PTHREAD_PRIO_PROTECT ? EINVAL : ENOTSUP);
+}
+
+int pthread_mutexattr_getprotocol (const pthread_mutexattr_t *attrp, int *ptp)
+{
+ *ptp = attrp->__protocol;
+ return (0);
+}
+
+int _pthread_mutex_init (pthread_mutex_t *mtxp,
+ const pthread_mutexattr_t *attrp)
+{
+ if (attrp == NULL)
+ attrp = &dfl_attr;
+
+ mtxp->__flags = (attrp->__pshared == PTHREAD_PROCESS_SHARED ?
+ GSYNC_SHARED : 0) | ((attrp->__prioceiling & PTHREAD_MUTEX_ROBUST) ?
+ PTHREAD_MUTEX_ROBUST : 0);
+
+ mtxp->__type = attrp->__mutex_type +
+ (attrp->__mutex_type != __PTHREAD_MUTEX_TIMED);
+
+ mtxp->__owner_id = 0;
+ mtxp->__shpid = 0;
+ mtxp->__cnt = 0;
+ mtxp->__lock = 0;
+
+ return (0);
+}
+
+strong_alias (_pthread_mutex_init, pthread_mutex_init)
+
+/* Lock routines. */
+
+/* Special ID used to signal an unrecoverable robust mutex. */
+#define NOTRECOVERABLE_ID (1U << 31)
+
+/* Common path for robust mutexes. Assumes the variable 'ret'
+ * is bound in the function this is called from. */
+#define ROBUST_LOCK(self, mtxp, cb, ...) \
+ if (mtxp->__owner_id == NOTRECOVERABLE_ID) \
+ return (ENOTRECOVERABLE); \
+ else if (mtxp->__owner_id == self->thread && \
+ __getpid () == (int)(mtxp->__lock & LLL_OWNER_MASK)) \
+ { \
+ if (mtxp->__type == PT_MTX_RECURSIVE) \
+ { \
+ if (__glibc_unlikely (mtxp->__cnt + 1 == 0)) \
+ return (EAGAIN); \
+ \
+ ++mtxp->__cnt; \
+ return (0); \
+ } \
+ else if (mtxp->__type == PT_MTX_ERRORCHECK) \
+ return (EDEADLK); \
+ } \
+ \
+ ret = cb (&mtxp->__lock, ##__VA_ARGS__); \
+ if (ret == 0 || ret == EOWNERDEAD) \
+ { \
+ if (mtxp->__owner_id == ENOTRECOVERABLE) \
+ ret = ENOTRECOVERABLE; \
+ else \
+ { \
+ mtxp->__owner_id = self->thread; \
+ mtxp->__cnt = 1; \
+ if (ret == EOWNERDEAD) \
+ { \
+ mtxp->__lock = mtxp->__lock | LLL_DEAD_OWNER; \
+ atomic_write_barrier (); \
+ } \
+ } \
+ } \
+ (void)0
+
+/* Check that a thread owns the mutex. For non-robust, task-shared
+ * objects, we have to check the thread *and* process-id. */
+#define mtx_owned_p(mtx, pt, flags) \
+ ((mtx)->__owner_id == (pt)->thread && \
+ (((flags) & GSYNC_SHARED) == 0 || \
+ (mtx)->__shpid == __getpid ()))
+
+/* Record a thread as the owner of the mutex. */
+#define mtx_set_owner(mtx, pt, flags) \
+ (void) \
+ ({ \
+ (mtx)->__owner_id = (pt)->thread; \
+ if ((flags) & GSYNC_SHARED) \
+ (mtx)->__shpid = __getpid (); \
+ })
+
+/* Redefined mutex types. The +1 is for binary compatibility. */
+#define PT_MTX_NORMAL __PTHREAD_MUTEX_TIMED
+#define PT_MTX_RECURSIVE (__PTHREAD_MUTEX_RECURSIVE + 1)
+#define PT_MTX_ERRORCHECK (__PTHREAD_MUTEX_ERRORCHECK + 1)
+
+/* Mutex type, including robustness. */
+#define MTX_TYPE(mtxp) \
+ ((mtxp)->__type | ((mtxp)->__flags & PTHREAD_MUTEX_ROBUST))
+
+extern int __getpid (void) __attribute__ ((const));
+
+int __pthread_mutex_lock (pthread_mutex_t *mtxp)
+{
+ struct __pthread *self;
+ int flags = mtxp->__flags & GSYNC_SHARED;
+ int ret = 0;
+
+ switch (MTX_TYPE (mtxp))
+ {
+ case PT_MTX_NORMAL:
+ lll_lock (&mtxp->__lock, flags);
+ break;
+
+ case PT_MTX_RECURSIVE:
+ self = _pthread_self ();
+ if (mtx_owned_p (mtxp, self, flags))
+ {
+ if (__glibc_unlikely (mtxp->__cnt + 1 == 0))
+ return (EAGAIN);
+
+ ++mtxp->__cnt;
+ return (ret);
+ }
+
+ lll_lock (&mtxp->__lock, flags);
+ mtx_set_owner (mtxp, self, flags);
+ mtxp->__cnt = 1;
+ break;
+
+ case PT_MTX_ERRORCHECK:
+ self = _pthread_self ();
+ if (mtx_owned_p (mtxp, self, flags))
+ return (EDEADLK);
+
+ lll_lock (&mtxp->__lock, flags);
+ mtx_set_owner (mtxp, self, flags);
+ break;
+
+ case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+ self = _pthread_self ();
+ ROBUST_LOCK (self, mtxp, lll_robust_lock, flags);
+ break;
+
+ default:
+ ret = EINVAL;
+ break;
+ }
+
+ return (ret);
+}
+
+strong_alias (__pthread_mutex_lock, _pthread_mutex_lock)
+strong_alias (__pthread_mutex_lock, pthread_mutex_lock)
+
+int __pthread_mutex_trylock (pthread_mutex_t *mtxp)
+{
+ struct __pthread *self;
+ int ret;
+
+ switch (MTX_TYPE (mtxp))
+ {
+ case PT_MTX_NORMAL:
+ ret = lll_trylock (&mtxp->__lock) == 0 ? 0 : EBUSY;
+ break;
+
+ case PT_MTX_RECURSIVE:
+ self = _pthread_self ();
+ if (mtx_owned_p (mtxp, self, mtxp->__flags))
+ {
+ if (__glibc_unlikely (mtxp->__cnt + 1 == 0))
+ return (EAGAIN);
+
+ ++mtxp->__cnt;
+ ret = 0;
+ }
+ else if ((ret = lll_trylock (&mtxp->__lock)) == 0)
+ {
+ mtx_set_owner (mtxp, self, mtxp->__flags);
+ mtxp->__cnt = 1;
+ }
+ else
+ ret = EBUSY;
+
+ break;
+
+ case PT_MTX_ERRORCHECK:
+ self = _pthread_self ();
+ if ((ret = lll_trylock (&mtxp->__lock)) == 0)
+ mtx_set_owner (mtxp, self, mtxp->__flags);
+ else
+ ret = EBUSY;
+ break;
+
+ case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+ self = _pthread_self ();
+ ROBUST_LOCK (self, mtxp, lll_robust_trylock);
+ break;
+
+ default:
+ ret = EINVAL;
+ break;
+ }
+
+ return (ret);
+}
+
+strong_alias (__pthread_mutex_trylock, _pthread_mutex_trylock)
+strong_alias (__pthread_mutex_trylock, pthread_mutex_trylock)
+
+int pthread_mutex_timedlock (pthread_mutex_t *mtxp,
+ const struct timespec *tsp)
+{
+ struct __pthread *self;
+ int ret, flags = mtxp->__flags & GSYNC_SHARED;
+
+ switch (MTX_TYPE (mtxp))
+ {
+ case PT_MTX_NORMAL:
+ ret = lll_abstimed_lock (&mtxp->__lock, tsp, flags);
+ break;
+
+ case PT_MTX_RECURSIVE:
+ self = _pthread_self ();
+ if (mtx_owned_p (mtxp, self, flags))
+ {
+ if (__glibc_unlikely (mtxp->__cnt + 1 == 0))
+ return (EAGAIN);
+
+ ++mtxp->__cnt;
+ ret = 0;
+ }
+ else if ((ret = lll_abstimed_lock (&mtxp->__lock,
+ tsp, flags)) == 0)
+ {
+ mtx_set_owner (mtxp, self, flags);
+ mtxp->__cnt = 1;
+ }
+
+ break;
+
+ case PT_MTX_ERRORCHECK:
+ self = _pthread_self ();
+ if (mtx_owned_p (mtxp, self, flags))
+ ret = EDEADLK;
+ else if ((ret = lll_abstimed_lock (&mtxp->__lock,
+ tsp, flags)) == 0)
+ mtx_set_owner (mtxp, self, flags);
+
+ break;
+
+ case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+ self = _pthread_self ();
+ ROBUST_LOCK (self, mtxp, lll_robust_abstimed_lock, tsp, flags);
+ break;
+
+ default:
+ ret = EINVAL;
+ break;
+ }
+
+ return (ret);
+}
+
+int __pthread_mutex_unlock (pthread_mutex_t *mtxp)
+{
+ struct __pthread *self;
+ int ret = 0, flags = mtxp->__flags & GSYNC_SHARED;
+
+ switch (MTX_TYPE (mtxp))
+ {
+ case PT_MTX_NORMAL:
+ lll_unlock (&mtxp->__lock, flags);
+ break;
+
+ case PT_MTX_RECURSIVE:
+ self = _pthread_self ();
+ if (!mtx_owned_p (mtxp, self, flags))
+ ret = EPERM;
+ else if (--mtxp->__cnt == 0)
+ {
+ mtxp->__owner_id = mtxp->__shpid = 0;
+ lll_unlock (&mtxp->__lock, flags);
+ }
+
+ break;
+
+ case PT_MTX_ERRORCHECK:
+ self = _pthread_self ();
+ if (!mtx_owned_p (mtxp, self, flags))
+ ret = EPERM;
+ else
+ {
+ mtxp->__owner_id = mtxp->__shpid = 0;
+ lll_unlock (&mtxp->__lock, flags);
+ }
+
+ break;
+
+ case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+ self = _pthread_self ();
+ if (mtxp->__owner_id == NOTRECOVERABLE_ID)
+ ; /* Nothing to do. */
+ else if (mtxp->__owner_id != self->thread ||
+ (int)(mtxp->__lock & LLL_OWNER_MASK) != __getpid ())
+ ret = EPERM;
+ else if (--mtxp->__cnt == 0)
+ {
+ /* Release the lock. If it's in an inconsistent
+ * state, mark it as irrecoverable. */
+ mtxp->__owner_id = (mtxp->__lock & LLL_DEAD_OWNER) ?
+ NOTRECOVERABLE_ID : 0;
+ lll_robust_unlock (&mtxp->__lock, flags);
+ }
+
+ break;
+
+ default:
+ ret = EINVAL;
+ break;
+ }
+
+ return (ret);
+}
+
+strong_alias (__pthread_mutex_unlock, _pthread_mutex_unlock)
+strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock)
+
+int pthread_mutex_consistent (pthread_mutex_t *mtxp)
+{
+ int ret = EINVAL;
+ unsigned int val = mtxp->__lock;
+
+ if ((mtxp->__flags & PTHREAD_MUTEX_ROBUST) != 0 &&
+ (val & LLL_DEAD_OWNER) != 0 &&
+ atomic_compare_and_exchange_bool_acq (&mtxp->__lock,
+ __getpid () | LLL_WAITERS, val) == 0)
+ {
+ /* The mutex is now ours, and it's consistent. */
+ mtxp->__owner_id = _pthread_self()->thread;
+ mtxp->__cnt = 1;
+ ret = 0;
+ }
+
+ return (ret);
+}
+
+weak_alias (pthread_mutex_consistent, pthread_mutex_consistent_np)
+
+int __pthread_mutex_transfer_np (pthread_mutex_t *mtxp, pthread_t th)
+{
+ struct __pthread *self = _pthread_self ();
+ struct __pthread *pt = __pthread_getid (th);
+
+ if (!pt)
+ return (ESRCH);
+ else if (pt == self)
+ return (0);
+
+ int ret = 0;
+ int flags = mtxp->__flags & GSYNC_SHARED;
+
+ switch (MTX_TYPE (mtxp))
+ {
+ case PT_MTX_NORMAL:
+ break;
+
+ case PT_MTX_RECURSIVE:
+ case PT_MTX_ERRORCHECK:
+ if (!mtx_owned_p (mtxp, self, flags))
+ ret = EPERM;
+ else
+ mtx_set_owner (mtxp, pt, flags);
+
+ break;
+
+ case PT_MTX_NORMAL | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_RECURSIVE | PTHREAD_MUTEX_ROBUST:
+ case PT_MTX_ERRORCHECK | PTHREAD_MUTEX_ROBUST:
+ /* Note that this can be used to transfer an inconsistent
+ * mutex as well. The new owner will still have the same
+ * flags as the original. */
+ if (mtxp->__owner_id != self->thread ||
+ (int)(mtxp->__lock & LLL_OWNER_MASK) != __getpid ())
+ ret = EPERM;
+ else
+ mtxp->__owner_id = pt->thread;
+
+ break;
+
+ default:
+ ret = EINVAL;
+ }
+
+ return (ret);
+}
+
+strong_alias (__pthread_mutex_transfer_np, pthread_mutex_transfer_np)
+
+int pthread_mutex_setprioceiling (pthread_mutex_t *mtxp, int cl, int *prp)
+{
+ (void)mtxp; (void)cl; (void)prp;
+ return (ENOSYS);
+}
+
+stub_warning (pthread_mutex_setprioceiling)
+
+int pthread_mutex_getprioceiling (const pthread_mutex_t *mtxp, int *clp)
+{
+ (void)mtxp; (void)clp;
+ return (ENOSYS);
+}
+
+stub_warning (pthread_mutex_getprioceiling)
+
+int _pthread_mutex_destroy (pthread_mutex_t *mtxp)
+{
+ atomic_read_barrier ();
+ if (*(volatile unsigned int *)&mtxp->__lock != 0)
+ return (EBUSY);
+
+ mtxp->__type = -1;
+ return (0);
+}
+
+strong_alias (_pthread_mutex_destroy, pthread_mutex_destroy)
+
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