Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdw/dwarf_formudata.c b/libdw/dwarf_formudata.c
new file mode 100644
index 0000000..e41981a
--- /dev/null
+++ b/libdw/dwarf_formudata.c
@@ -0,0 +1,231 @@
+/* Return unsigned constant represented by attribute.
+   Copyright (C) 2003-2012, 2014 Red Hat, Inc.
+   This file is part of elfutils.
+   Written by Ulrich Drepper <drepper@redhat.com>, 2003.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <dwarf.h>
+#include "libdwP.h"
+
+internal_function unsigned char *
+__libdw_formptr (Dwarf_Attribute *attr, int sec_index,
+		 int err_nodata, unsigned char **endpp,
+		 Dwarf_Off *offsetp)
+{
+  if (attr == NULL)
+    return NULL;
+
+  const Elf_Data *d = attr->cu->dbg->sectiondata[sec_index];
+  if (unlikely (d == NULL))
+    {
+      __libdw_seterrno (err_nodata);
+      return NULL;
+    }
+
+  Dwarf_Word offset;
+  if (attr->form == DW_FORM_sec_offset)
+    {
+      if (__libdw_read_offset (attr->cu->dbg, attr->cu->dbg,
+			       cu_sec_idx (attr->cu), attr->valp,
+			       attr->cu->offset_size, &offset, sec_index, 0))
+	return NULL;
+    }
+  else if (attr->cu->version > 3)
+    goto invalid;
+  else
+    switch (attr->form)
+      {
+      case DW_FORM_data4:
+      case DW_FORM_data8:
+	if (__libdw_read_offset (attr->cu->dbg, attr->cu->dbg,
+				 cu_sec_idx (attr->cu),
+				 attr->valp,
+				 attr->form == DW_FORM_data4 ? 4 : 8,
+				 &offset, sec_index, 0))
+	  return NULL;
+	break;
+
+      default:
+	if (INTUSE(dwarf_formudata) (attr, &offset))
+	  return NULL;
+      };
+
+  unsigned char *readp = d->d_buf + offset;
+  unsigned char *endp = d->d_buf + d->d_size;
+  if (unlikely (readp >= endp))
+    {
+    invalid:
+      __libdw_seterrno (DWARF_E_INVALID_DWARF);
+      return NULL;
+    }
+
+  if (endpp != NULL)
+    *endpp = endp;
+  if (offsetp != NULL)
+    *offsetp = offset;
+  return readp;
+}
+
+int
+dwarf_formudata (Dwarf_Attribute *attr, Dwarf_Word *return_uval)
+{
+  if (attr == NULL)
+    return -1;
+
+  const unsigned char *datap = attr->valp;
+  const unsigned char *endp = attr->cu->endp;
+
+  switch (attr->form)
+    {
+    case DW_FORM_data1:
+      if (datap + 1 > endp)
+	{
+	invalid:
+	  __libdw_seterrno (DWARF_E_INVALID_DWARF);
+	  return -1;
+	}
+      *return_uval = *attr->valp;
+      break;
+
+    case DW_FORM_data2:
+      if (datap + 2 > endp)
+	goto invalid;
+      *return_uval = read_2ubyte_unaligned (attr->cu->dbg, attr->valp);
+      break;
+
+    case DW_FORM_data4:
+    case DW_FORM_data8:
+    case DW_FORM_sec_offset:
+      /* Before DWARF4 data4 and data8 are pure constants unless the
+	 attribute also allows offsets (*ptr classes), since DWARF4
+	 they are always just constants (start_scope is special though,
+	 since it only could express a rangelist since DWARF4).  */
+      if (attr->form == DW_FORM_sec_offset
+	  || (attr->cu->version < 4 && attr->code != DW_AT_start_scope))
+	{
+	  switch (attr->code)
+	    {
+	    case DW_AT_data_member_location:
+	    case DW_AT_frame_base:
+	    case DW_AT_location:
+	    case DW_AT_return_addr:
+	    case DW_AT_segment:
+	    case DW_AT_static_link:
+	    case DW_AT_string_length:
+	    case DW_AT_use_location:
+	    case DW_AT_vtable_elem_location:
+	      /* loclistptr */
+	      if (__libdw_formptr (attr, IDX_debug_loc,
+				   DWARF_E_NO_LOCLIST, NULL,
+				   return_uval) == NULL)
+		return -1;
+	      break;
+
+	    case DW_AT_macro_info:
+	      /* macptr into .debug_macinfo */
+	      if (__libdw_formptr (attr, IDX_debug_macinfo,
+				   DWARF_E_NO_ENTRY, NULL,
+				   return_uval) == NULL)
+		return -1;
+	      break;
+
+	    case DW_AT_GNU_macros:
+	      /* macptr into .debug_macro */
+	      if (__libdw_formptr (attr, IDX_debug_macro,
+				   DWARF_E_NO_ENTRY, NULL,
+				   return_uval) == NULL)
+		return -1;
+	      break;
+
+	    case DW_AT_ranges:
+	    case DW_AT_start_scope:
+	      /* rangelistptr */
+	      if (__libdw_formptr (attr, IDX_debug_ranges,
+				   DWARF_E_NO_DEBUG_RANGES, NULL,
+				   return_uval) == NULL)
+		return -1;
+	      break;
+
+	    case DW_AT_stmt_list:
+	      /* lineptr */
+	      if (__libdw_formptr (attr, IDX_debug_line,
+				   DWARF_E_NO_DEBUG_LINE, NULL,
+				   return_uval) == NULL)
+		return -1;
+	      break;
+
+	    default:
+	      /* sec_offset can only be used by one of the above attrs.  */
+	      if (attr->form == DW_FORM_sec_offset)
+		{
+		  __libdw_seterrno (DWARF_E_INVALID_DWARF);
+		  return -1;
+		}
+
+	      /* Not one of the special attributes, just a constant.  */
+	      if (__libdw_read_address (attr->cu->dbg, cu_sec_idx (attr->cu),
+					attr->valp,
+					attr->form == DW_FORM_data4 ? 4 : 8,
+					return_uval))
+		return -1;
+	      break;
+	    }
+	}
+      else
+	{
+	  /* We are dealing with a constant data4 or data8.  */
+	  if (__libdw_read_address (attr->cu->dbg, cu_sec_idx (attr->cu),
+				    attr->valp,
+				    attr->form == DW_FORM_data4 ? 4 : 8,
+				    return_uval))
+	    return -1;
+	}
+      break;
+
+    case DW_FORM_sdata:
+      if (datap + 1 > endp)
+	goto invalid;
+      get_sleb128 (*return_uval, datap, endp);
+      break;
+
+    case DW_FORM_udata:
+      if (datap + 1 > endp)
+	goto invalid;
+      get_uleb128 (*return_uval, datap, endp);
+      break;
+
+    default:
+      __libdw_seterrno (DWARF_E_NO_CONSTANT);
+      return -1;
+    }
+
+  return 0;
+}
+INTDEF(dwarf_formudata)