glibc/nptl_db/td_thr_tls_get_addr.c
2003-03-10 19:21:23 +00:00

79 lines
2.5 KiB
C

/* Get address of thread local variable.
Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <stddef.h>
#include <link.h>
#include "thread_dbP.h"
/* Value used for dtv entries for which the allocation is delayed. */
# define TLS_DTV_UNALLOCATED ((void *) -1l)
td_err_e
td_thr_tls_get_addr (const td_thrhandle_t *th __attribute__ ((unused)),
void *map_address __attribute__ ((unused)),
size_t offset __attribute__ ((unused)),
void **address __attribute__ ((unused)))
{
#if USE_TLS
size_t modid;
union dtv pdtv, *dtvp;
LOG ("td_thr_tls_get_addr");
psaddr_t dtvpp = th->th_unique;
#if TLS_TCB_AT_TP
dtvpp += offsetof (struct pthread, dtv);
#elif TLS_DTV_AT_TP
dtvpp += TLS_PRE_TCB_SIZE + offsetof (tcbhead_t, dtv);
#else
# error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined."
#endif
/* Get the DTV pointer from the thread descriptor. */
if (ps_pdread (th->th_ta_p->ph, dtvpp, &dtvp, sizeof dtvp) != PS_OK)
return TD_ERR; /* XXX Other error value? */
/* Read the module ID from the link_map. */
if (ps_pdread (th->th_ta_p->ph,
&((struct link_map *) map_address)->l_tls_modid,
&modid, sizeof modid) != PS_OK)
return TD_ERR; /* XXX Other error value? */
/* Get the corresponding entry in the DTV. */
if (ps_pdread (th->th_ta_p->ph, dtvp + modid,
&pdtv, sizeof (union dtv)) != PS_OK)
return TD_ERR; /* XXX Other error value? */
/* It could be that the memory for this module is not allocated for
the given thread. */
if (pdtv.pointer == TLS_DTV_UNALLOCATED)
/* There is not much we can do. */
return TD_NOTALLOC;
*address = (char *) pdtv.pointer + offset;
return TD_OK;
#else
return TD_ERR;
#endif
}