diff options
Diffstat (limited to 'src/libdw/dwarf_siblingof.c')
| -rw-r--r-- | src/libdw/dwarf_siblingof.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/src/libdw/dwarf_siblingof.c b/src/libdw/dwarf_siblingof.c new file mode 100644 index 00000000..f8e54c18 --- /dev/null +++ b/src/libdw/dwarf_siblingof.c @@ -0,0 +1,159 @@ +/* Return sibling of given DIE. + Copyright (C) 2003-2010 Red Hat, Inc. + This file is part of Red Hat elfutils. + Written by Ulrich Drepper <drepper@redhat.com>, 2003. + + 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" +#include <dwarf.h> +#include <string.h> + + +int +dwarf_siblingof (die, result) + Dwarf_Die *die; + Dwarf_Die *result; +{ + /* Ignore previous errors. */ + if (die == NULL) + return -1; + + if (result == NULL) + return -1; + + if (result != die) + result->addr = NULL; + + unsigned int level = 0; + + /* Copy of the current DIE. */ + Dwarf_Die this_die = *die; + /* Temporary attributes we create. */ + Dwarf_Attribute sibattr; + /* Copy of the CU in the request. */ + sibattr.cu = this_die.cu; + /* That's the address we start looking. */ + unsigned char *addr = this_die.addr; + /* End of the buffer. */ + unsigned char *endp + = ((unsigned char *) cu_data (sibattr.cu)->d_buf + sibattr.cu->end); + + /* Search for the beginning of the next die on this level. We + must not return the dies for children of the given die. */ + do + { + /* Find the end of the DIE or the sibling attribute. */ + addr = __libdw_find_attr (&this_die, DW_AT_sibling, &sibattr.code, + &sibattr.form); + if (sibattr.code == DW_AT_sibling) + { + Dwarf_Off offset; + sibattr.valp = addr; + if (unlikely (__libdw_formref (&sibattr, &offset) != 0)) + /* Something went wrong. */ + return -1; + + /* Compute the next address. */ + addr = ((unsigned char *) cu_data (sibattr.cu)->d_buf + + sibattr.cu->start + offset); + } + else if (unlikely (addr == NULL) + || unlikely (this_die.abbrev == DWARF_END_ABBREV)) + return -1; + else if (this_die.abbrev->has_children) + /* This abbreviation has children. */ + ++level; + + + while (1) + { + /* Make sure we are still in range. Some producers might skip + the trailing NUL bytes. */ + if (addr >= endp) + return 1; + + if (*addr != '\0') + break; + + if (level-- == 0) + { + if (result != die) + result->addr = addr; + /* No more sibling at all. */ + return 1; + } + + ++addr; + } + + /* Initialize the 'current DIE'. */ + this_die.addr = addr; + this_die.abbrev = NULL; + } + while (level > 0); + + /* Maybe we reached the end of the CU. */ + if (addr >= endp) + return 1; + + /* Clear the entire DIE structure. This signals we have not yet + determined any of the information. */ + memset (result, '\0', sizeof (Dwarf_Die)); + + /* We have the address. */ + result->addr = addr; + + /* Same CU as the parent. */ + result->cu = sibattr.cu; + + return 0; +} +INTDEF(dwarf_siblingof) |