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_getattrs.c b/libdw/dwarf_getattrs.c
new file mode 100644
index 0000000..7f55faf
--- /dev/null
+++ b/libdw/dwarf_getattrs.c
@@ -0,0 +1,110 @@
+/* Get attributes of the DIE.
+ Copyright (C) 2004, 2005, 2008, 2009, 2014, 2017 Red Hat, Inc.
+ This file is part of elfutils.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+ 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 "libdwP.h"
+
+
+ptrdiff_t
+dwarf_getattrs (Dwarf_Die *die, int (*callback) (Dwarf_Attribute *, void *),
+ void *arg, ptrdiff_t offset)
+{
+ if (die == NULL)
+ return -1l;
+
+ if (unlikely (offset == 1))
+ return 1;
+
+ const unsigned char *die_addr;
+
+ /* Find the abbreviation entry. */
+ Dwarf_Abbrev *abbrevp = __libdw_dieabbrev (die, &die_addr);
+
+ if (unlikely (abbrevp == DWARF_END_ABBREV))
+ {
+ __libdw_seterrno (DWARF_E_INVALID_DWARF);
+ return -1l;
+ }
+
+ /* This is where the attributes start. */
+ const unsigned char *attrp = abbrevp->attrp;
+ const unsigned char *const offset_attrp = abbrevp->attrp + offset;
+
+ /* Go over the list of attributes. */
+ while (1)
+ {
+ /* Get attribute name and form. Dwarf_Abbrev was checked when
+ created, so we can read unchecked. */
+ Dwarf_Attribute attr;
+ const unsigned char *remembered_attrp = attrp;
+
+ get_uleb128_unchecked (attr.code, attrp);
+ get_uleb128_unchecked (attr.form, attrp);
+
+ /* We can stop if we found the attribute with value zero. */
+ if (attr.code == 0 && attr.form == 0)
+ /* Do not return 0 here - there would be no way to
+ distinguish this value from the attribute at offset 0.
+ Instead we return +1 which would never be a valid
+ offset of an attribute. */
+ return 1l;
+
+ /* If we are not to OFFSET_ATTRP yet, we just have to skip
+ the values of the intervening attributes. */
+ if (remembered_attrp >= offset_attrp)
+ {
+ /* Fill in the rest. */
+ attr.valp = (unsigned char *) die_addr;
+ attr.cu = die->cu;
+
+ /* Now call the callback function. */
+ if (callback (&attr, arg) != DWARF_CB_OK)
+ /* Return the offset of the start of the attribute, so that
+ dwarf_getattrs() can be restarted from this point if the
+ caller so desires. */
+ return remembered_attrp - abbrevp->attrp;
+ }
+
+ /* Skip over the rest of this attribute (if there is any). */
+ if (attr.form != 0)
+ {
+ size_t len = __libdw_form_val_len (die->cu, attr.form, die_addr);
+ if (unlikely (len == (size_t) -1l))
+ /* Something wrong with the file. */
+ return -1l;
+
+ // __libdw_form_val_len will have done a bounds check.
+ die_addr += len;
+ }
+ }
+ /* NOTREACHED */
+}