glibc/nptl_db/td_thr_tsd.c

97 lines
2.9 KiB
C

/* Get a thread-specific data pointer for a thread.
Copyright (C) 1999-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 1999.
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
<http://www.gnu.org/licenses/>. */
#include <stdint.h>
#include "thread_dbP.h"
td_err_e
td_thr_tsd (const td_thrhandle_t *th, const thread_key_t tk, void **data)
{
td_err_e err;
psaddr_t tk_seq, level1, level2, seq, value;
void *copy;
uint32_t pthread_key_2ndlevel_size, idx1st, idx2nd;
LOG ("td_thr_tsd");
/* Get the key entry. */
err = DB_GET_VALUE (tk_seq, th->th_ta_p, __pthread_keys, tk);
if (err == TD_NOAPLIC)
return TD_BADKEY;
if (err != TD_OK)
return err;
/* Fail if this key is not at all used. */
if (((uintptr_t) tk_seq & 1) == 0)
return TD_BADKEY;
/* This makes sure we have the size information on hand. */
err = DB_GET_FIELD_ADDRESS (level2, th->th_ta_p, 0, pthread_key_data_level2,
data, 1);
if (err != TD_OK)
return err;
/* Compute the indeces. */
pthread_key_2ndlevel_size
= DB_DESC_NELEM (th->th_ta_p->ta_field_pthread_key_data_level2_data);
idx1st = tk / pthread_key_2ndlevel_size;
idx2nd = tk % pthread_key_2ndlevel_size;
/* Now fetch the first level pointer. */
err = DB_GET_FIELD (level1, th->th_ta_p, th->th_unique, pthread,
specific, idx1st);
if (err == TD_NOAPLIC)
return TD_DBERR;
if (err != TD_OK)
return err;
/* Check the pointer to the second level array. */
if (level1 == 0)
return TD_NOTSD;
/* Locate the element within the second level array. */
err = DB_GET_FIELD_ADDRESS (level2, th->th_ta_p,
level1, pthread_key_data_level2, data, idx2nd);
if (err == TD_NOAPLIC)
return TD_DBERR;
if (err != TD_OK)
return err;
/* Now copy in that whole structure. */
err = DB_GET_STRUCT (copy, th->th_ta_p, level2, pthread_key_data);
if (err != TD_OK)
return err;
/* Check whether the data is valid. */
err = DB_GET_FIELD_LOCAL (seq, th->th_ta_p, copy, pthread_key_data, seq, 0);
if (err != TD_OK)
return err;
if (seq != tk_seq)
return TD_NOTSD;
/* Finally, fetch the value. */
err = DB_GET_FIELD_LOCAL (value, th->th_ta_p, copy, pthread_key_data,
data, 0);
if (err == TD_OK)
*data = value;
return err;
}