diff options
Diffstat (limited to 'libdw/dwarf_ranges.c')
| -rw-r--r-- | libdw/dwarf_ranges.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/libdw/dwarf_ranges.c b/libdw/dwarf_ranges.c new file mode 100644 index 00000000..546bcac0 --- /dev/null +++ b/libdw/dwarf_ranges.c @@ -0,0 +1,121 @@ +/* Enumerate the PC ranges covered by a DIE. + Copyright (C) 2005 Red Hat, Inc. + + This program is Open Source software; you can redistribute it and/or + modify it under the terms of the Open Software License version 1.0 as + published by the Open Source Initiative. + + You should have received a copy of the Open Software License along + with this program; if not, you may obtain a copy of the Open Software + License version 1.0 from http://www.opensource.org/licenses/osl.php or + by writing the Open Source Initiative c/o Lawrence Rosen, Esq., + 3001 King Ranch Road, Ukiah, CA 95482. */ + +#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 = + { + .cu = attr->cu, + .addr = ((char *) attr->cu->dbg->sectiondata[IDX_debug_info]->d_buf + + attr->cu->start + 3 * attr->cu->offset_size - 4 + 3), + }; + if (INTUSE(dwarf_lowpc) (&cudie, basep) != 0) + 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) + { + __libdw_seterrno (DWARF_E_INVALID_DWARF); + return -1; + } + + 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); + } + else + { + begin = (Dwarf_Sword) read_4sbyte_unaligned_inc (die->cu->dbg, + readp); + end = read_4ubyte_unaligned_inc (die->cu->dbg, readp); + } + + if (begin == (Dwarf_Addr) -1l) /* 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) |