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diff --git a/nsprpub/pr/src/threads/prtpd.c b/nsprpub/pr/src/threads/prtpd.c
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+** Thread Private Data
+**
+** There is an aribitrary limit on the number of keys that will be allocated
+** by the runtime. It's largish, so it is intended to be a sanity check, not
+** an impediment.
+**
+** There is a counter, initialized to zero and incremented every time a
+** client asks for a new key, that holds the high water mark for keys. All
+** threads logically have the same high water mark and are permitted to
+** ask for TPD up to that key value.
+**
+** The vector to hold the TPD are allocated when PR_SetThreadPrivate() is
+** called. The size of the vector will be some value greater than or equal
+** to the current high water mark. Each thread has its own TPD length and
+** vector.
+**
+** Threads that get private data for keys they have not set (or perhaps
+** don't even exist for that thread) get a NULL return. If the key is
+** beyond the high water mark, an error will be returned.
+*/
+
+/*
+** As of this time, BeOS has its own TPD implementation. Integrating
+** this standard one is a TODO for anyone with a bit of spare time on
+** their hand. For now, we just #ifdef out this whole file and use
+** the routines in pr/src/btthreads/
+*/
+
+#ifndef XP_BEOS
+
+#include "primpl.h"
+
+#include <string.h>
+
+#if defined(WIN95)
+/*
+** Some local variables report warnings on Win95 because the code paths
+** using them are conditioned on HAVE_CUSTOME_USER_THREADS.
+** The pragma suppresses the warning.
+**
+*/
+#pragma warning(disable : 4101)
+#endif
+
+#define _PR_TPD_LIMIT 128 /* arbitary limit on the TPD slots */
+static PRInt32 _pr_tpd_length = 0; /* current length of destructor vector */
+static PRInt32 _pr_tpd_highwater = 0; /* next TPD key to be assigned */
+static PRThreadPrivateDTOR *_pr_tpd_destructors = NULL;
+ /* the destructors are associated with
+ the keys, therefore asserting that
+ the TPD key depicts the data's 'type' */
+
+/*
+** Initialize the thread private data manipulation
+*/
+void _PR_InitTPD(void)
+{
+ _pr_tpd_destructors = (PRThreadPrivateDTOR*)
+ PR_CALLOC(_PR_TPD_LIMIT * sizeof(PRThreadPrivateDTOR*));
+ PR_ASSERT(NULL != _pr_tpd_destructors);
+ _pr_tpd_length = _PR_TPD_LIMIT;
+}
+
+/*
+** Clean up the thread private data manipulation
+*/
+void _PR_CleanupTPD(void)
+{
+} /* _PR_CleanupTPD */
+
+/*
+** This routine returns a new index for per-thread-private data table.
+** The index is visible to all threads within a process. This index can
+** be used with the PR_SetThreadPrivate() and PR_GetThreadPrivate() routines
+** to save and retrieve data associated with the index for a thread.
+**
+** The index independently maintains specific values for each binding thread.
+** A thread can only get access to its own thread-specific-data.
+**
+** Upon a new index return the value associated with the index for all threads
+** is NULL, and upon thread creation the value associated with all indices for
+** that thread is NULL.
+**
+** "dtor" is the destructor function to invoke when the private
+** data is set or destroyed
+**
+** Returns PR_FAILURE if the total number of indices will exceed the maximun
+** allowed.
+*/
+
+PR_IMPLEMENT(PRStatus) PR_NewThreadPrivateIndex(
+ PRUintn *newIndex, PRThreadPrivateDTOR dtor)
+{
+ PRStatus rv;
+ PRInt32 index;
+
+ if (!_pr_initialized) _PR_ImplicitInitialization();
+
+ PR_ASSERT(NULL != newIndex);
+ PR_ASSERT(NULL != _pr_tpd_destructors);
+
+ index = PR_ATOMIC_INCREMENT(&_pr_tpd_highwater) - 1; /* allocate index */
+ if (_PR_TPD_LIMIT <= index)
+ {
+ PR_SetError(PR_TPD_RANGE_ERROR, 0);
+ rv = PR_FAILURE; /* that's just wrong */
+ }
+ else
+ {
+ _pr_tpd_destructors[index] = dtor; /* record destructor @index */
+ *newIndex = (PRUintn)index; /* copy into client's location */
+ rv = PR_SUCCESS; /* that's okay */
+ }
+
+ return rv;
+}
+
+/*
+** Define some per-thread-private data.
+** "index" is an index into the per-thread private data table
+** "priv" is the per-thread-private data
+**
+** If the per-thread private data table has a previously registered
+** destructor function and a non-NULL per-thread-private data value,
+** the destructor function is invoked.
+**
+** This can return PR_FAILURE if index is invalid (ie., beyond the limit
+** on the TPD slots) or memory is insufficient to allocate an expanded
+** vector.
+*/
+
+PR_IMPLEMENT(PRStatus) PR_SetThreadPrivate(PRUintn index, void *priv)
+{
+ PRThread *self = PR_GetCurrentThread();
+
+ /*
+ ** To improve performance, we don't check if the index has been
+ ** allocated.
+ */
+ if (index >= _PR_TPD_LIMIT)
+ {
+ PR_SetError(PR_TPD_RANGE_ERROR, 0);
+ return PR_FAILURE;
+ }
+
+ PR_ASSERT(((NULL == self->privateData) && (0 == self->tpdLength))
+ || ((NULL != self->privateData) && (0 != self->tpdLength)));
+
+ /*
+ ** If this thread does not have a sufficient vector for the index
+ ** being set, go ahead and extend this vector now.
+ */
+ if ((NULL == self->privateData) || (self->tpdLength <= index))
+ {
+ void *extension = PR_CALLOC(_pr_tpd_length * sizeof(void*));
+ if (NULL == extension)
+ {
+ PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
+ return PR_FAILURE;
+ }
+ if (self->privateData) {
+ (void)memcpy(
+ extension, self->privateData,
+ self->tpdLength * sizeof(void*));
+ PR_DELETE(self->privateData);
+ }
+ self->tpdLength = _pr_tpd_length;
+ self->privateData = (void**)extension;
+ }
+ /*
+ ** There wasn't much chance of having to call the destructor
+ ** unless the slot already existed.
+ */
+ else if (self->privateData[index] && _pr_tpd_destructors[index])
+ {
+ void *data = self->privateData[index];
+ self->privateData[index] = NULL;
+ (*_pr_tpd_destructors[index])(data);
+ }
+
+ PR_ASSERT(index < self->tpdLength);
+ self->privateData[index] = priv;
+
+ return PR_SUCCESS;
+}
+
+/*
+** Recover the per-thread-private data for the current thread. "index" is
+** the index into the per-thread private data table.
+**
+** The returned value may be NULL which is indistinguishable from an error
+** condition.
+**
+*/
+
+PR_IMPLEMENT(void*) PR_GetThreadPrivate(PRUintn index)
+{
+ PRThread *self = PR_GetCurrentThread();
+ void *tpd = ((NULL == self->privateData) || (index >= self->tpdLength)) ?
+ NULL : self->privateData[index];
+
+ return tpd;
+}
+
+/*
+** Destroy the thread's private data, if any exists. This is called at
+** thread termination time only. There should be no threading issues
+** since this is being called by the thread itself.
+*/
+void _PR_DestroyThreadPrivate(PRThread* self)
+{
+#define _PR_TPD_DESTRUCTOR_ITERATIONS 4
+
+ if (NULL != self->privateData) /* we have some */
+ {
+ PRBool clean;
+ PRUint32 index;
+ PRInt32 passes = _PR_TPD_DESTRUCTOR_ITERATIONS;
+ PR_ASSERT(0 != self->tpdLength);
+ do
+ {
+ clean = PR_TRUE;
+ for (index = 0; index < self->tpdLength; ++index)
+ {
+ void *priv = self->privateData[index]; /* extract */
+ if (NULL != priv) /* we have data at this index */
+ {
+ if (NULL != _pr_tpd_destructors[index])
+ {
+ self->privateData[index] = NULL; /* precondition */
+ (*_pr_tpd_destructors[index])(priv); /* destroy */
+ clean = PR_FALSE; /* unknown side effects */
+ }
+ }
+ }
+ } while ((--passes > 0) && !clean); /* limit # of passes */
+ /*
+ ** We give up after a fixed number of passes. Any non-NULL
+ ** thread-private data value with a registered destructor
+ ** function is not destroyed.
+ */
+ memset(self->privateData, 0, self->tpdLength * sizeof(void*));
+ }
+} /* _PR_DestroyThreadPrivate */
+
+#endif /* !XP_BEOS */