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-rw-r--r--linuxthreads_db/td_thr_tlsbase.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/linuxthreads_db/td_thr_tlsbase.c b/linuxthreads_db/td_thr_tlsbase.c
new file mode 100644
index 0000000000..081e8d0e70
--- /dev/null
+++ b/linuxthreads_db/td_thr_tlsbase.c
@@ -0,0 +1,71 @@
+/* Locate TLS data for a thread.
+   Copyright (C) 2003, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#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;
+
+#if USE_TLS
+  union dtv pdtv, *dtvp;
+
+  LOG ("td_thr_tlsbase");
+
+  psaddr_t dtvpp = th->th_unique;
+#if TLS_TCB_AT_TP
+  dtvpp += offsetof (struct _pthread_descr_struct, p_header.data.dtvp);
+#elif 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 == TLS_DTV_UNALLOCATED)
+    return TD_TLSDEFER;
+
+  *base = (char *) pdtv.pointer;
+
+  return TD_OK;
+#else
+  return TD_ERR;
+#endif
+}