diff options
Diffstat (limited to 'libdw/dwarf_ranges.c')
| -rw-r--r-- | libdw/dwarf_ranges.c | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/libdw/dwarf_ranges.c b/libdw/dwarf_ranges.c new file mode 100644 index 00000000..89da0af4 --- /dev/null +++ b/libdw/dwarf_ranges.c @@ -0,0 +1,169 @@ +/* Enumerate the PC ranges covered by a DIE. + Copyright (C) 2005, 2007 Red Hat, Inc. + This file is part of Red Hat elfutils. + + 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 <assert.h> + + +ptrdiff_t +dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, + Dwarf_Addr *startp, Dwarf_Addr *endp) +{ + if (die == NULL) + return -1; + + if (offset == 0 + /* Usually there is a single contiguous range. */ + && INTUSE(dwarf_highpc) (die, endp) == 0 + && INTUSE(dwarf_lowpc) (die, startp) == 0) + /* A offset into .debug_ranges will never be 1, it must be at least a + multiple of 4. So we can return 1 as a special case value to mark + there are no ranges to look for on the next call. */ + return 1; + + if (offset == 1) + return 0; + + /* We have to look for a noncontiguous range. */ + + const Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_ranges]; + if (d == NULL) + { + __libdw_seterrno (DWARF_E_NO_DEBUG_RANGES); + return -1; + } + + if (offset == 0) + { + Dwarf_Attribute attr_mem; + Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, DW_AT_ranges, + &attr_mem); + if (attr == NULL) + return -1; + + /* Must have the form data4 or data8 which act as an offset. */ + Dwarf_Word start_offset; + if (INTUSE(dwarf_formudata) (attr, &start_offset) != 0) + return -1; + + offset = start_offset; + assert ((Dwarf_Word) offset == start_offset); + + /* Fetch the CU's base address. */ + Dwarf_Die cudie = CUDIE (attr->cu); + + /* Find the base address of the compilation unit. It will + normally be specified by DW_AT_low_pc. In DWARF-3 draft 4, + the base address could be overridden by DW_AT_entry_pc. It's + been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc + for compilation units with discontinuous ranges. */ + if (unlikely (INTUSE(dwarf_lowpc) (&cudie, basep) != 0) + && INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie, + DW_AT_entry_pc, + &attr_mem), + basep) != 0) + { + if (INTUSE(dwarf_errno) () == 0) + { + invalid: + __libdw_seterrno (DWARF_E_INVALID_DWARF); + } + return -1; + } + } + else if (offset < 0 || (size_t) offset >= d->d_size) + { + __libdw_seterrno (DWARF_E_INVALID_OFFSET); + return -1l; + } + + unsigned char *readp = d->d_buf + offset; + + next: + if ((unsigned char *) d->d_buf + d->d_size - readp + < die->cu->address_size * 2) + goto invalid; + + Dwarf_Addr begin; + Dwarf_Addr end; + if (die->cu->address_size == 8) + { + begin = read_8ubyte_unaligned_inc (die->cu->dbg, readp); + end = read_8ubyte_unaligned_inc (die->cu->dbg, readp); + if (begin == (uint64_t) -1l) /* Base address entry. */ + { + *basep = end; + goto next; + } + } + else + { + begin = read_4ubyte_unaligned_inc (die->cu->dbg, readp); + end = read_4ubyte_unaligned_inc (die->cu->dbg, readp); + if (begin == (uint32_t) -1) /* Base address entry. */ + { + *basep = end; + goto next; + } + } + + if (begin == 0 && end == 0) /* End of list entry. */ + return 0; + + /* We have an address range entry. */ + *startp = *basep + begin; + *endp = *basep + end; + return readp - (unsigned char *) d->d_buf; +} +INTDEF (dwarf_ranges) |