diff options
Diffstat (limited to 'src/libdw/dwarf_getattrs.c')
| -rw-r--r-- | src/libdw/dwarf_getattrs.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/src/libdw/dwarf_getattrs.c b/src/libdw/dwarf_getattrs.c new file mode 100644 index 00000000..051dc25f --- /dev/null +++ b/src/libdw/dwarf_getattrs.c @@ -0,0 +1,146 @@ +/* Get attributes of the DIE. + Copyright (C) 2004, 2005, 2008, 2009 Red Hat, Inc. + This file is part of Red Hat elfutils. + Written by Ulrich Drepper <drepper@redhat.com>, 2004. + + Red Hat elfutils is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by the + Free Software Foundation; version 2 of the License. + + Red Hat 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 a copy of the GNU General Public License along + with Red Hat elfutils; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. + + In addition, as a special exception, Red Hat, Inc. gives You the + additional right to link the code of Red Hat elfutils with code licensed + under any Open Source Initiative certified open source license + (http://www.opensource.org/licenses/index.php) which requires the + distribution of source code with any binary distribution and to + distribute linked combinations of the two. Non-GPL Code permitted under + this exception must only link to the code of Red Hat elfutils through + those well defined interfaces identified in the file named EXCEPTION + found in the source code files (the "Approved Interfaces"). The files + of Non-GPL Code may instantiate templates or use macros or inline + functions from the Approved Interfaces without causing the resulting + work to be covered by the GNU General Public License. Only Red Hat, + Inc. may make changes or additions to the list of Approved Interfaces. + Red Hat's grant of this exception is conditioned upon your not adding + any new exceptions. If you wish to add a new Approved Interface or + exception, please contact Red Hat. You must obey the GNU General Public + License in all respects for all of the Red Hat elfutils code and other + code used in conjunction with Red Hat elfutils except the Non-GPL Code + covered by this exception. If you modify this file, you may extend this + exception to your version of the file, but you are not obligated to do + so. If you do not wish to provide this exception without modification, + you must delete this exception statement from your version and license + this file solely under the GPL without exception. + + Red Hat elfutils is an included package of the Open Invention Network. + An included package of the Open Invention Network is a package for which + Open Invention Network licensees cross-license their patents. No patent + license is granted, either expressly or impliedly, by designation as an + included package. Should you wish to participate in the Open Invention + Network licensing program, please visit www.openinventionnetwork.com + <http://www.openinventionnetwork.com>. */ + +#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 = die->addr; + + /* Get the abbreviation code. */ + unsigned int u128; + get_uleb128 (u128, die_addr); + + if (die->abbrev == NULL) + /* Find the abbreviation. */ + die->abbrev = __libdw_findabbrev (die->cu, u128); + + if (unlikely (die->abbrev == DWARF_END_ABBREV)) + { + invalid_dwarf: + __libdw_seterrno (DWARF_E_INVALID_DWARF); + return -1l; + } + + /* This is where the attributes start. */ + const unsigned char *attrp = die->abbrev->attrp; + const unsigned char *const offset_attrp = die->abbrev->attrp + offset; + + /* Go over the list of attributes. */ + Dwarf *dbg = die->cu->dbg; + while (1) + { + /* Are we still in bounds? */ + if (unlikely (attrp + >= ((unsigned char *) dbg->sectiondata[IDX_debug_abbrev]->d_buf + + dbg->sectiondata[IDX_debug_abbrev]->d_size))) + goto invalid_dwarf; + + /* Get attribute name and form. */ + Dwarf_Attribute attr; + const unsigned char *remembered_attrp = attrp; + + // XXX Fix bound checks + get_uleb128 (attr.code, attrp); + get_uleb128 (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 - die->abbrev->attrp; + } + + /* Skip over the rest of this attribute (if there is any). */ + if (attr.form != 0) + { + size_t len = __libdw_form_val_len (dbg, die->cu, attr.form, + die_addr); + + if (unlikely (len == (size_t) -1l)) + /* Something wrong with the file. */ + return -1l; + + // XXX We need better boundary checks. + die_addr += len; + } + } + /* NOTREACHED */ +} |