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/* Deallocation thread-specific data structures related to pthread_key_create.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <pthreadP.h>
/* Deallocate POSIX thread-local-storage. */
void
__nptl_deallocate_tsd (void)
{
struct pthread *self = THREAD_SELF;
/* Maybe no data was ever allocated. This happens often so we have
a flag for this. */
if (THREAD_GETMEM (self, specific_used))
{
size_t round;
size_t cnt;
round = 0;
do
{
size_t idx;
/* So far no new nonzero data entry. */
THREAD_SETMEM (self, specific_used, false);
for (cnt = idx = 0; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
{
struct pthread_key_data *level2;
level2 = THREAD_GETMEM_NC (self, specific, cnt);
if (level2 != NULL)
{
size_t inner;
for (inner = 0; inner < PTHREAD_KEY_2NDLEVEL_SIZE;
++inner, ++idx)
{
void *data = level2[inner].data;
if (data != NULL)
{
/* Always clear the data. */
level2[inner].data = NULL;
/* Make sure the data corresponds to a valid
key. This test fails if the key was
deallocated and also if it was
re-allocated. It is the user's
responsibility to free the memory in this
case. */
if (level2[inner].seq
== __pthread_keys[idx].seq
/* It is not necessary to register a destructor
function. */
&& __pthread_keys[idx].destr != NULL)
/* Call the user-provided destructor. */
__pthread_keys[idx].destr (data);
}
}
}
else
idx += PTHREAD_KEY_1STLEVEL_SIZE;
}
if (THREAD_GETMEM (self, specific_used) == 0)
/* No data has been modified. */
goto just_free;
}
/* We only repeat the process a fixed number of times. */
while (__builtin_expect (++round < PTHREAD_DESTRUCTOR_ITERATIONS, 0));
/* Just clear the memory of the first block for reuse. */
memset (&THREAD_SELF->specific_1stblock, '\0',
sizeof (self->specific_1stblock));
just_free:
/* Free the memory for the other blocks. */
for (cnt = 1; cnt < PTHREAD_KEY_1STLEVEL_SIZE; ++cnt)
{
struct pthread_key_data *level2;
level2 = THREAD_GETMEM_NC (self, specific, cnt);
if (level2 != NULL)
{
/* The first block is allocated as part of the thread
descriptor. */
free (level2);
THREAD_SETMEM_NC (self, specific, cnt, NULL);
}
}
THREAD_SETMEM (self, specific_used, false);
}
}
libc_hidden_def (__nptl_deallocate_tsd)
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