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Diffstat (limited to 'libpthread/linuxthreads_db/td_thr_tlsbase.c')
-rw-r--r--libpthread/linuxthreads_db/td_thr_tlsbase.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/libpthread/linuxthreads_db/td_thr_tlsbase.c b/libpthread/linuxthreads_db/td_thr_tlsbase.c
new file mode 100644
index 000000000..ac86c42fe
--- /dev/null
+++ b/libpthread/linuxthreads_db/td_thr_tlsbase.c
@@ -0,0 +1,70 @@
+/* Locate TLS data for a thread.
+ Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
+ 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
+ <http://www.gnu.org/licenses/>. */
+
+#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_tlsbase (const td_thrhandle_t *th,
+ unsigned long int modid,
+ psaddr_t *base)
+{
+ if (modid < 1)
+ return TD_NOTLS;
+
+#ifdef __UCLIBC_HAS_TLS__
+ union dtv pdtv, *dtvp;
+
+ LOG ("td_thr_tlsbase");
+
+ psaddr_t dtvpp = th->th_unique;
+#if defined(TLS_TCB_AT_TP)
+ dtvpp += offsetof (struct _pthread_descr_struct, p_header.data.dtvp);
+#elif defined(TLS_DTV_AT_TP)
+/* Special case hack. If TLS_TCB_SIZE == 0 (on PowerPC), there is no TCB
+ containing the DTV at the TP, but actually the TCB lies behind the TP,
+ i.e. at the very end of the area covered by TLS_PRE_TCB_SIZE. */
+ dtvpp += TLS_PRE_TCB_SIZE + offsetof (tcbhead_t, dtv)
+ - (TLS_TCB_SIZE == 0 ? sizeof (tcbhead_t) : 0);
+#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? */
+
+ /* 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.val == TLS_DTV_UNALLOCATED)
+ return TD_TLSDEFER;
+
+ *base = (char *) pdtv.pointer.val;
+
+ return TD_OK;
+#else
+ return TD_ERR;
+#endif
+}