static signed fde_pointer_type(const u32 *cie)
{
const u8 *ptr = (const u8 *)(cie + 2);
unsigned version = *ptr;
if (version != 1)
return -1; /* unsupported */
if (*++ptr) {
const char *aug;
const u8 *end = (const u8 *)(cie + 1) + *cie;
uleb128_t len;
/* check if augmentation size is first (and thus present) */
if (*ptr != 'z')
return -1;
/* check if augmentation string is nul-terminated */
if ((ptr = memchr(aug = (const void *)ptr, 0, end - ptr)) == NULL)
return -1;
++ptr; /* skip terminator */
get_uleb128(&ptr, end); /* skip code alignment */
get_sleb128(&ptr, end); /* skip data alignment */
/* skip return address column */
version <= 1 ? (void)++ptr : (void)get_uleb128(&ptr, end);
len = get_uleb128(&ptr, end); /* augmentation length */
if (ptr + len < ptr || ptr + len > end)
return -1;
end = ptr + len;
while (*++aug) {
if (ptr >= end)
return -1;
switch(*aug) {
case 'L':
++ptr;
break;
case 'P': {
signed ptrType = *ptr++;
if (!read_pointer(&ptr, end, ptrType) || ptr > end)
return -1;
}
break;
case 'R':
return *ptr;
default:
return -1;
}
}
}
return DW_EH_PE_native|DW_EH_PE_abs;
}
static int
get_member_offset(Dwarf_Die *memdie, Dwarf_Word *off_out)
{
Dwarf_Attribute loc_attr;
Dwarf_Block block;
if (dwarf_attr_integrate(memdie, DW_AT_data_member_location, &loc_attr)
== NULL)
dwarf_err(EX_DATAERR, "dwarf_attr_integrate(%s/loc)",
dwarf_diename(memdie));
switch (dwarf_whatform(&loc_attr)) {
case DW_FORM_block:
case DW_FORM_block1:
case DW_FORM_block2:
case DW_FORM_block4:
if (dwarf_formblock(&loc_attr, &block))
dwarf_err(EX_DATAERR, "dwarf_formblock(%s)",
dwarf_diename(memdie));
assert(block.data[0] == DW_OP_plus_uconst ||
block.data[0] == DW_OP_constu);
get_uleb128(off_out, &block.data[1]);
return (0);
default:
printf("ZZZ!\n");
return (-1);
}
}
static struct dwarf_fde *
intern_fde (Dwarf_CFI *cache, const Dwarf_FDE *entry)
{
/* Look up the new entry's CIE. */
struct dwarf_cie *cie = __libdw_find_cie (cache, entry->CIE_pointer);
if (cie == NULL)
return (void *) -1l;
struct dwarf_fde *fde = malloc (sizeof (struct dwarf_fde));
if (fde == NULL)
{
__libdw_seterrno (DWARF_E_NOMEM);
return NULL;
}
fde->instructions = entry->start;
fde->instructions_end = entry->end;
if (unlikely (read_encoded_value (cache, cie->fde_encoding,
&fde->instructions, &fde->start))
|| unlikely (read_encoded_value (cache, cie->fde_encoding & 0x0f,
&fde->instructions, &fde->end)))
{
free (fde);
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return NULL;
}
fde->end += fde->start;
fde->cie = cie;
if (cie->sized_augmentation_data)
{
/* The CIE augmentation says the FDE has a DW_FORM_block
before its actual instruction stream. */
Dwarf_Word len;
get_uleb128 (len, fde->instructions, fde->instructions_end);
if ((Dwarf_Word) (fde->instructions_end - fde->instructions) < len)
{
free (fde);
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return NULL;
}
fde->instructions += len;
}
else
/* We had to understand all of the CIE augmentation string.
We've recorded the number of data bytes in FDEs. */
fde->instructions += cie->fde_augmentation_data_size;
/* Add the new entry to the search tree. */
if (tsearch (fde, &cache->fde_tree, &compare_fde) == NULL)
{
free (fde);
__libdw_seterrno (DWARF_E_NOMEM);
return NULL;
}
return fde;
}
int
dwarf_hasattr (Dwarf_Die *die, unsigned int search_name)
{
if (die == NULL)
return 0;
/* Find the abbreviation entry. */
Dwarf_Abbrev *abbrevp = __libdw_dieabbrev (die, NULL);
if (unlikely (abbrevp == DWARF_END_ABBREV))
{
invalid_dwarf:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return 0;
}
Dwarf *dbg = die->cu->dbg;
/* Search the name attribute. */
unsigned char *const endp
= ((unsigned char *) dbg->sectiondata[IDX_debug_abbrev]->d_buf
+ dbg->sectiondata[IDX_debug_abbrev]->d_size);
const unsigned char *attrp = abbrevp->attrp;
while (1)
{
/* Are we still in bounds? This test needs to be refined. */
if (unlikely (attrp >= endp))
goto invalid_dwarf;
/* Get attribute name and form. */
unsigned int attr_name;
get_uleb128 (attr_name, attrp, endp);
unsigned int attr_form;
if (unlikely (attrp >= endp))
goto invalid_dwarf;
get_uleb128 (attr_form, attrp, endp);
/* We can stop if we found the attribute with value zero. */
if (attr_name == 0 || attr_form == 0)
return 0;
if (attr_name == search_name)
return 1;
}
}
int
dwarf_formblock (Dwarf_Attribute *attr, Dwarf_Block *return_block)
{
if (attr == NULL)
return -1;
const unsigned char *datap = attr->valp;
const unsigned char *endp = attr->cu->endp;
switch (attr->form)
{
case DW_FORM_block1:
if (unlikely (endp - datap < 1))
goto invalid;
return_block->length = *(uint8_t *) attr->valp;
return_block->data = attr->valp + 1;
break;
case DW_FORM_block2:
if (unlikely (endp - datap < 2))
goto invalid;
return_block->length = read_2ubyte_unaligned (attr->cu->dbg, attr->valp);
return_block->data = attr->valp + 2;
break;
case DW_FORM_block4:
if (unlikely (endp - datap < 4))
goto invalid;
return_block->length = read_4ubyte_unaligned (attr->cu->dbg, attr->valp);
return_block->data = attr->valp + 4;
break;
case DW_FORM_block:
case DW_FORM_exprloc:
if (unlikely (endp - datap < 1))
goto invalid;
get_uleb128 (return_block->length, datap, endp);
return_block->data = (unsigned char *) datap;
break;
default:
__libdw_seterrno (DWARF_E_NO_BLOCK);
return -1;
}
if (unlikely (return_block->length > (size_t) (endp - return_block->data)))
{
/* Block does not fit. */
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
return 0;
}
internal_function_def
__libdw_find_attr (Dwarf_Die *die, unsigned int search_name,
unsigned int *codep, unsigned int *formp)
{
Dwarf *dbg = die->cu->dbg;
unsigned char *readp = (unsigned char *) die->addr;
/* First we have to get the abbreviation code so that we can decode
the data in the DIE. */
unsigned int abbrev_code;
get_uleb128 (abbrev_code, readp);
/* Find the abbreviation entry. */
Dwarf_Abbrev *abbrevp = die->abbrev;
if (abbrevp == NULL)
{
abbrevp = __libdw_findabbrev (die->cu, abbrev_code);
die->abbrev = abbrevp ?: (Dwarf_Abbrev *) -1l;
}
int
dwarf_getlocation_implicit_value (Dwarf_Attribute *attr, const Dwarf_Op *op,
Dwarf_Block *return_block)
{
if (attr == NULL)
return -1;
struct loc_block_s fake = { .addr = (void *) op };
struct loc_block_s **found = tfind (&fake, &attr->cu->locs, loc_compare);
if (unlikely (found == NULL))
{
__libdw_seterrno (DWARF_E_NO_BLOCK);
return -1;
}
return_block->length = (*found)->length;
return_block->data = (*found)->data;
return 0;
}
/* DW_AT_data_member_location can be a constant as well as a loclistptr.
Only data[48] indicate a loclistptr. */
static int
check_constant_offset (Dwarf_Attribute *attr,
Dwarf_Op **llbuf, size_t *listlen)
{
if (attr->code != DW_AT_data_member_location)
return 1;
switch (attr->form)
{
/* Punt for any non-constant form. */
default:
return 1;
case DW_FORM_data1:
case DW_FORM_data2:
case DW_FORM_data4:
case DW_FORM_data8:
case DW_FORM_sdata:
case DW_FORM_udata:
break;
}
/* Check whether we already cached this location. */
struct loc_s fake = { .addr = attr->valp };
struct loc_s **found = tfind (&fake, &attr->cu->locs, loc_compare);
if (found == NULL)
{
Dwarf_Word offset;
if (INTUSE(dwarf_formudata) (attr, &offset) != 0)
return -1;
Dwarf_Op *result = libdw_alloc (attr->cu->dbg,
Dwarf_Op, sizeof (Dwarf_Op), 1);
result->atom = DW_OP_plus_uconst;
result->number = offset;
result->number2 = 0;
result->offset = 0;
/* Insert a record in the search tree so we can find it again later. */
struct loc_s *newp = libdw_alloc (attr->cu->dbg,
struct loc_s, sizeof (struct loc_s),
1);
newp->addr = attr->valp;
newp->loc = result;
newp->nloc = 1;
found = tsearch (newp, &attr->cu->locs, loc_compare);
}
assert ((*found)->nloc == 1);
if (llbuf != NULL)
{
*llbuf = (*found)->loc;
*listlen = 1;
}
return 0;
}
int
internal_function
__libdw_intern_expression (Dwarf *dbg, bool other_byte_order,
unsigned int address_size, unsigned int ref_size,
void **cache, const Dwarf_Block *block,
bool cfap, bool valuep,
Dwarf_Op **llbuf, size_t *listlen, int sec_index)
{
/* Empty location expressions don't have any ops to intern. */
if (block->length == 0)
{
*listlen = 0;
return 0;
}
/* Check whether we already looked at this list. */
struct loc_s fake = { .addr = block->data };
struct loc_s **found = tfind (&fake, cache, loc_compare);
if (found != NULL)
{
/* We already saw it. */
*llbuf = (*found)->loc;
*listlen = (*found)->nloc;
if (valuep)
{
assert (*listlen > 1);
assert ((*llbuf)[*listlen - 1].atom == DW_OP_stack_value);
}
return 0;
}
const unsigned char *data = block->data;
const unsigned char *const end_data = data + block->length;
const struct { bool other_byte_order; } bo = { other_byte_order };
struct loclist *loclist = NULL;
unsigned int n = 0;
/* Stack allocate at most this many locs. */
#define MAX_STACK_LOCS 256
struct loclist stack_locs[MAX_STACK_LOCS];
#define NEW_LOC() ({ struct loclist *ll; \
ll = (likely (n < MAX_STACK_LOCS) \
? &stack_locs[n] \
: malloc (sizeof (struct loclist))); \
if (unlikely (ll == NULL)) \
goto nomem; \
n++; \
ll->next = loclist; \
loclist = ll; \
ll; })
if (cfap)
{
/* Synthesize the operation to push the CFA before the expression. */
struct loclist *newloc = NEW_LOC ();
newloc->atom = DW_OP_call_frame_cfa;
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = -1;
}
/* Decode the opcodes. It is possible in some situations to have a
block of size zero. */
while (data < end_data)
{
struct loclist *newloc;
newloc = NEW_LOC ();
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
switch ((newloc->atom = *data++))
{
case DW_OP_addr:
/* Address, depends on address size of CU. */
if (dbg == NULL)
{
// XXX relocation?
if (address_size == 4)
{
if (unlikely (data + 4 > end_data))
goto invalid;
else
newloc->number = read_4ubyte_unaligned_inc (&bo, data);
}
else
{
if (unlikely (data + 8 > end_data))
goto invalid;
else
newloc->number = read_8ubyte_unaligned_inc (&bo, data);
}
}
else if (__libdw_read_address_inc (dbg, sec_index, &data,
address_size, &newloc->number))
goto invalid;
break;
case DW_OP_call_ref:
/* DW_FORM_ref_addr, depends on offset size of CU. */
if (dbg == NULL || __libdw_read_offset_inc (dbg, sec_index, &data,
ref_size,
&newloc->number,
IDX_debug_info, 0))
goto invalid;
break;
case DW_OP_deref:
case DW_OP_dup:
case DW_OP_drop:
case DW_OP_over:
case DW_OP_swap:
case DW_OP_rot:
case DW_OP_xderef:
case DW_OP_abs:
case DW_OP_and:
case DW_OP_div:
case DW_OP_minus:
case DW_OP_mod:
case DW_OP_mul:
case DW_OP_neg:
case DW_OP_not:
case DW_OP_or:
case DW_OP_plus:
case DW_OP_shl:
case DW_OP_shr:
case DW_OP_shra:
case DW_OP_xor:
case DW_OP_eq:
case DW_OP_ge:
case DW_OP_gt:
case DW_OP_le:
case DW_OP_lt:
case DW_OP_ne:
case DW_OP_lit0 ... DW_OP_lit31:
case DW_OP_reg0 ... DW_OP_reg31:
case DW_OP_nop:
case DW_OP_push_object_address:
case DW_OP_call_frame_cfa:
case DW_OP_form_tls_address:
case DW_OP_GNU_push_tls_address:
case DW_OP_stack_value:
/* No operand. */
break;
case DW_OP_const1u:
case DW_OP_pick:
case DW_OP_deref_size:
case DW_OP_xderef_size:
if (unlikely (data >= end_data))
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
returnmem:
/* Free any dynamicly allocated loclists, if any. */
while (n > MAX_STACK_LOCS)
{
struct loclist *loc = loclist;
loclist = loc->next;
free (loc);
n--;
}
return -1;
}
newloc->number = *data++;
break;
case DW_OP_const1s:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *((int8_t *) data);
++data;
break;
case DW_OP_const2u:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const2s:
case DW_OP_skip:
case DW_OP_bra:
case DW_OP_call2:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_const4u:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const4s:
case DW_OP_call4:
case DW_OP_GNU_parameter_ref:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_const8u:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const8s:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_constu:
case DW_OP_plus_uconst:
case DW_OP_regx:
case DW_OP_piece:
case DW_OP_GNU_convert:
case DW_OP_GNU_reinterpret:
get_uleb128 (newloc->number, data, end_data);
break;
case DW_OP_consts:
case DW_OP_breg0 ... DW_OP_breg31:
case DW_OP_fbreg:
get_sleb128 (newloc->number, data, end_data);
break;
case DW_OP_bregx:
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
get_sleb128 (newloc->number2, data, end_data);
break;
case DW_OP_bit_piece:
case DW_OP_GNU_regval_type:
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
get_uleb128 (newloc->number2, data, end_data);
break;
case DW_OP_implicit_value:
case DW_OP_GNU_entry_value:
/* This cannot be used in a CFI expression. */
if (unlikely (dbg == NULL))
goto invalid;
/* start of block inc. len. */
newloc->number2 = (Dwarf_Word) (uintptr_t) data;
get_uleb128 (newloc->number, data, end_data); /* Block length. */
if (unlikely ((Dwarf_Word) (end_data - data) < newloc->number))
goto invalid;
data += newloc->number; /* Skip the block. */
break;
case DW_OP_GNU_implicit_pointer:
/* DW_FORM_ref_addr, depends on offset size of CU. */
if (dbg == NULL || __libdw_read_offset_inc (dbg, sec_index, &data,
ref_size,
&newloc->number,
IDX_debug_info, 0))
goto invalid;
if (unlikely (data >= end_data))
goto invalid;
get_uleb128 (newloc->number2, data, end_data); /* Byte offset. */
break;
case DW_OP_GNU_deref_type:
if (unlikely (data + 1 >= end_data))
goto invalid;
newloc->number = *data++;
get_uleb128 (newloc->number2, data, end_data);
break;
case DW_OP_GNU_const_type:
{
size_t size;
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
/* start of block inc. len. */
newloc->number2 = (Dwarf_Word) (uintptr_t) data;
size = *data++;
if (unlikely ((Dwarf_Word) (end_data - data) < size))
goto invalid;
data += size; /* Skip the block. */
}
break;
default:
goto invalid;
}
}
if (unlikely (n == 0))
{
/* This is not allowed.
It would mean an empty location expression, which we handled
already as a special case above. */
goto invalid;
}
if (valuep)
{
struct loclist *newloc = NEW_LOC ();
newloc->atom = DW_OP_stack_value;
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
}
/* Allocate the array. */
Dwarf_Op *result;
if (dbg != NULL)
result = libdw_alloc (dbg, Dwarf_Op, sizeof (Dwarf_Op), n);
else
{
result = malloc (sizeof *result * n);
if (result == NULL)
{
nomem:
__libdw_seterrno (DWARF_E_NOMEM);
goto returnmem;
}
}
/* Store the result. */
*llbuf = result;
*listlen = n;
do
{
/* We populate the array from the back since the list is backwards. */
--n;
result[n].atom = loclist->atom;
result[n].number = loclist->number;
result[n].number2 = loclist->number2;
result[n].offset = loclist->offset;
if (result[n].atom == DW_OP_implicit_value)
store_implicit_value (dbg, cache, &result[n]);
struct loclist *loc = loclist;
loclist = loclist->next;
if (unlikely (n + 1 > MAX_STACK_LOCS))
free (loc);
}
while (n > 0);
/* Insert a record in the search tree so that we can find it again later. */
struct loc_s *newp;
if (dbg != NULL)
newp = libdw_alloc (dbg, struct loc_s, sizeof (struct loc_s), 1);
else
{
newp = malloc (sizeof *newp);
if (newp == NULL)
{
free (result);
goto nomem;
}
}
newp->addr = block->data;
newp->loc = result;
newp->nloc = *listlen;
(void) tsearch (newp, cache, loc_compare);
/* We did it. */
return 0;
}
static int
getlocation (struct Dwarf_CU *cu, const Dwarf_Block *block,
Dwarf_Op **llbuf, size_t *listlen, int sec_index)
{
/* Empty location expressions don't have any ops to intern.
Note that synthetic empty_cu doesn't have an associated DWARF dbg. */
if (block->length == 0)
{
*listlen = 0;
return 0;
}
return __libdw_intern_expression (cu->dbg, cu->dbg->other_byte_order,
cu->address_size, (cu->version == 2
? cu->address_size
: cu->offset_size),
&cu->locs, block,
false, false,
llbuf, listlen, sec_index);
}
int
dwarf_getlocation (Dwarf_Attribute *attr, Dwarf_Op **llbuf, size_t *listlen)
{
if (! attr_ok (attr))
return -1;
int result = check_constant_offset (attr, llbuf, listlen);
if (result != 1)
return result;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) != 0)
return -1;
return getlocation (attr->cu, &block, llbuf, listlen, cu_sec_idx (attr->cu));
}
static int
attr_base_address (Dwarf_Attribute *attr, Dwarf_Addr *basep)
{
/* 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. */
Dwarf_Attribute attr_mem;
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)
return -1;
/* The compiler provided no base address when it should
have. Buggy GCC does this when it used absolute
addresses in the location list and no DW_AT_ranges. */
*basep = 0;
}
return 0;
}
int
dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines **lines, size_t *nlines)
{
if (unlikely (cudie == NULL
|| INTUSE(dwarf_tag) (cudie) != DW_TAG_compile_unit))
return -1;
int res = -1;
/* Get the information if it is not already known. */
struct Dwarf_CU *const cu = cudie->cu;
if (cu->lines == NULL)
{
/* Failsafe mode: no data found. */
cu->lines = (void *) -1l;
cu->files = (void *) -1l;
/* The die must have a statement list associated. */
Dwarf_Attribute stmt_list_mem;
Dwarf_Attribute *stmt_list = INTUSE(dwarf_attr) (cudie, DW_AT_stmt_list,
&stmt_list_mem);
/* Get the offset into the .debug_line section. NB: this call
also checks whether the previous dwarf_attr call failed. */
Dwarf_Word offset;
if (INTUSE(dwarf_formudata) (stmt_list, &offset) != 0)
goto out;
Dwarf *dbg = cu->dbg;
if (dbg->sectiondata[IDX_debug_line] == NULL)
{
__libdw_seterrno (DWARF_E_NO_DEBUG_LINE);
goto out;
}
const uint8_t *linep = dbg->sectiondata[IDX_debug_line]->d_buf + offset;
const uint8_t *lineendp = (dbg->sectiondata[IDX_debug_line]->d_buf
+ dbg->sectiondata[IDX_debug_line]->d_size);
/* Get the compilation directory. */
Dwarf_Attribute compdir_attr_mem;
Dwarf_Attribute *compdir_attr = INTUSE(dwarf_attr) (cudie,
DW_AT_comp_dir,
&compdir_attr_mem);
const char *comp_dir = INTUSE(dwarf_formstring) (compdir_attr);
if (unlikely (linep + 4 > lineendp))
{
invalid_data:
__libdw_seterrno (DWARF_E_INVALID_DEBUG_LINE);
goto out;
}
Dwarf_Word unit_length = read_4ubyte_unaligned_inc (dbg, linep);
unsigned int length = 4;
if (unlikely (unit_length == DWARF3_LENGTH_64_BIT))
{
if (unlikely (linep + 8 > lineendp))
goto invalid_data;
unit_length = read_8ubyte_unaligned_inc (dbg, linep);
length = 8;
}
/* Check whether we have enough room in the section. */
if (unit_length < 2 + length + 5 * 1
|| unlikely (linep + unit_length > lineendp))
goto invalid_data;
lineendp = linep + unit_length;
/* The next element of the header is the version identifier. */
uint_fast16_t version = read_2ubyte_unaligned_inc (dbg, linep);
if (unlikely (version > DWARF_VERSION))
{
__libdw_seterrno (DWARF_E_VERSION);
goto out;
}
/* Next comes the header length. */
Dwarf_Word header_length;
if (length == 4)
header_length = read_4ubyte_unaligned_inc (dbg, linep);
else
header_length = read_8ubyte_unaligned_inc (dbg, linep);
const unsigned char *header_start = linep;
/* Next the minimum instruction length. */
uint_fast8_t minimum_instr_len = *linep++;
/* Then the flag determining the default value of the is_stmt
register. */
uint_fast8_t default_is_stmt = *linep++;
/* Now the line base. */
int_fast8_t line_base = *((int_fast8_t *) linep);
++linep;
/* And the line range. */
uint_fast8_t line_range = *linep++;
/* The opcode base. */
uint_fast8_t opcode_base = *linep++;
/* Remember array with the standard opcode length (-1 to account for
the opcode with value zero not being mentioned). */
const uint8_t *standard_opcode_lengths = linep - 1;
linep += opcode_base - 1;
if (unlikely (linep >= lineendp))
goto invalid_data;
/* First comes the list of directories. Add the compilation
directory first since the index zero is used for it. */
struct dirlist
{
const char *dir;
size_t len;
struct dirlist *next;
} comp_dir_elem =
{
.dir = comp_dir,
.len = comp_dir ? strlen (comp_dir) : 0,
.next = NULL
};
struct dirlist *dirlist = &comp_dir_elem;
unsigned int ndirlist = 1;
// XXX Directly construct array to conserve memory?
while (*linep != 0)
{
struct dirlist *new_dir =
(struct dirlist *) alloca (sizeof (*new_dir));
new_dir->dir = (char *) linep;
uint8_t *endp = memchr (linep, '\0', lineendp - linep);
if (endp == NULL)
goto invalid_data;
new_dir->len = endp - linep;
new_dir->next = dirlist;
dirlist = new_dir;
++ndirlist;
linep = endp + 1;
}
/* Skip the final NUL byte. */
++linep;
/* Rearrange the list in array form. */
struct dirlist **dirarray
= (struct dirlist **) alloca (ndirlist * sizeof (*dirarray));
for (unsigned int n = ndirlist; n-- > 0; dirlist = dirlist->next)
dirarray[n] = dirlist;
/* Now read the files. */
struct filelist null_file =
{
.info =
{
.name = "???",
.mtime = 0,
.length = 0
},
.next = NULL
};
struct filelist *filelist = &null_file;
unsigned int nfilelist = 1;
if (unlikely (linep >= lineendp))
goto invalid_data;
while (*linep != 0)
{
struct filelist *new_file =
(struct filelist *) alloca (sizeof (*new_file));
/* First comes the file name. */
char *fname = (char *) linep;
uint8_t *endp = memchr (fname, '\0', lineendp - linep);
if (endp == NULL)
goto invalid_data;
size_t fnamelen = endp - (uint8_t *) fname;
linep = endp + 1;
/* Then the index. */
Dwarf_Word diridx;
get_uleb128 (diridx, linep);
if (unlikely (diridx >= ndirlist))
{
__libdw_seterrno (DWARF_E_INVALID_DIR_IDX);
goto out;
}
if (*fname == '/')
/* It's an absolute path. */
new_file->info.name = fname;
else
{
new_file->info.name = libdw_alloc (dbg, char, 1,
dirarray[diridx]->len + 1
+ fnamelen + 1);
char *cp = new_file->info.name;
if (dirarray[diridx]->dir != NULL)
{
/* This value could be NULL in case the DW_AT_comp_dir
was not present. We cannot do much in this case.
The easiest thing is to convert the path in an
absolute path. */
cp = stpcpy (cp, dirarray[diridx]->dir);
}
*cp++ = '/';
strcpy (cp, fname);
assert (strlen (new_file->info.name)
< dirarray[diridx]->len + 1 + fnamelen + 1);
}
/* Next comes the modification time. */
get_uleb128 (new_file->info.mtime, linep);
/* Finally the length of the file. */
get_uleb128 (new_file->info.length, linep);
new_file->next = filelist;
filelist = new_file;
++nfilelist;
}
/* Skip the final NUL byte. */
++linep;
/* Consistency check. */
if (unlikely (linep != header_start + header_length))
{
__libdw_seterrno (DWARF_E_INVALID_DWARF);
goto out;
}
/* We are about to process the statement program. Initialize the
state machine registers (see 6.2.2 in the v2.1 specification). */
Dwarf_Word address = 0;
size_t file = 1;
size_t line = 1;
size_t column = 0;
uint_fast8_t is_stmt = default_is_stmt;
int basic_block = 0;
int prologue_end = 0;
int epilogue_begin = 0;
/* Process the instructions. */
struct linelist *linelist = NULL;
unsigned int nlinelist = 0;
while (linep < lineendp)
{
struct linelist *new_line;
unsigned int opcode;
unsigned int u128;
int s128;
/* Read the opcode. */
opcode = *linep++;
/* Is this a special opcode? */
if (likely (opcode >= opcode_base))
{
/* Yes. Handling this is quite easy since the opcode value
is computed with
opcode = (desired line increment - line_base)
+ (line_range * address advance) + opcode_base
*/
int line_increment = (line_base
+ (opcode - opcode_base) % line_range);
unsigned int address_increment = (minimum_instr_len
* ((opcode - opcode_base)
/ line_range));
/* Perform the increments. */
line += line_increment;
address += address_increment;
/* Add a new line with the current state machine values. */
NEW_LINE (0);
/* Reset the flags. */
basic_block = 0;
prologue_end = 0;
epilogue_begin = 0;
}
else if (opcode == 0)
{
/* This an extended opcode. */
if (unlikely (linep + 2 > lineendp))
goto invalid_data;
/* The length. */
unsigned int len = *linep++;
if (unlikely (linep + len > lineendp))
goto invalid_data;
/* The sub-opcode. */
opcode = *linep++;
switch (opcode)
{
case DW_LNE_end_sequence:
/* Add a new line with the current state machine values.
The is the end of the sequence. */
NEW_LINE (1);
/* Reset the registers. */
address = 0;
file = 1;
line = 1;
column = 0;
is_stmt = default_is_stmt;
basic_block = 0;
prologue_end = 0;
epilogue_begin = 0;
break;
case DW_LNE_set_address:
/* The value is an address. The size is defined as
apporiate for the target machine. We use the
address size field from the CU header. */
if (cu->address_size == 4)
address = read_4ubyte_unaligned_inc (dbg, linep);
else
address = read_8ubyte_unaligned_inc (dbg, linep);
break;
case DW_LNE_define_file:
{
char *fname = (char *) linep;
uint8_t *endp = memchr (linep, '\0', lineendp - linep);
if (endp == NULL)
goto invalid_data;
size_t fnamelen = endp - linep;
linep = endp + 1;
unsigned int diridx;
get_uleb128 (diridx, linep);
Dwarf_Word mtime;
get_uleb128 (mtime, linep);
Dwarf_Word filelength;
get_uleb128 (filelength, linep);
struct filelist *new_file =
(struct filelist *) alloca (sizeof (*new_file));
if (fname[0] == '/')
new_file->info.name = fname;
else
{
new_file->info.name =
libdw_alloc (dbg, char, 1, (dirarray[diridx]->len + 1
+ fnamelen + 1));
char *cp = new_file->info.name;
if (dirarray[diridx]->dir != NULL)
/* This value could be NULL in case the
DW_AT_comp_dir was not present. We
cannot do much in this case. The easiest
thing is to convert the path in an
absolute path. */
cp = stpcpy (cp, dirarray[diridx]->dir);
*cp++ = '/';
strcpy (cp, fname);
}
new_file->info.mtime = mtime;
new_file->info.length = filelength;
new_file->next = filelist;
filelist = new_file;
++nfilelist;
}
break;
default:
/* Unknown, ignore it. */
linep += len - 1;
break;
}
}
else if (opcode <= DW_LNS_set_epilogue_begin)
{
/* This is a known standard opcode. */
switch (opcode)
{
case DW_LNS_copy:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
/* Add a new line with the current state machine values. */
NEW_LINE (0);
/* Reset the flags. */
basic_block = 0;
/* XXX Whether the following two lines are necessary is
unclear. I guess the current v2.1 specification has
a bug in that it says clearing these two registers is
not necessary. */
prologue_end = 0;
epilogue_begin = 0;
break;
case DW_LNS_advance_pc:
/* Takes one uleb128 parameter which is added to the
address. */
if (unlikely (standard_opcode_lengths[opcode] != 1))
goto invalid_data;
get_uleb128 (u128, linep);
address += minimum_instr_len * u128;
break;
case DW_LNS_advance_line:
/* Takes one sleb128 parameter which is added to the
line. */
if (unlikely (standard_opcode_lengths[opcode] != 1))
goto invalid_data;
get_sleb128 (s128, linep);
line += s128;
break;
case DW_LNS_set_file:
/* Takes one uleb128 parameter which is stored in file. */
if (unlikely (standard_opcode_lengths[opcode] != 1))
goto invalid_data;
get_uleb128 (u128, linep);
file = u128;
break;
case DW_LNS_set_column:
/* Takes one uleb128 parameter which is stored in column. */
if (unlikely (standard_opcode_lengths[opcode] != 1))
goto invalid_data;
get_uleb128 (u128, linep);
column = u128;
break;
case DW_LNS_negate_stmt:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
is_stmt = 1 - is_stmt;
break;
case DW_LNS_set_basic_block:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
basic_block = 1;
break;
case DW_LNS_const_add_pc:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
address += (minimum_instr_len
* ((255 - opcode_base) / line_range));
break;
case DW_LNS_fixed_advance_pc:
/* Takes one 16 bit parameter which is added to the
address. */
if (unlikely (standard_opcode_lengths[opcode] != 1))
goto invalid_data;
address += read_2ubyte_unaligned_inc (dbg, linep);
break;
case DW_LNS_set_prologue_end:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
prologue_end = 1;
break;
case DW_LNS_set_epilogue_begin:
/* Takes no argument. */
if (unlikely (standard_opcode_lengths[opcode] != 0))
goto invalid_data;
epilogue_begin = 1;
break;
}
}
else
{
/* This is a new opcode the generator but not we know about.
Read the parameters associated with it but then discard
everything. Read all the parameters for this opcode. */
for (int n = standard_opcode_lengths[opcode]; n > 0; --n)
get_uleb128 (u128, linep);
/* Next round, ignore this opcode. */
continue;
}
}
static int
getlocation (struct Dwarf_CU *cu, const Dwarf_Block *block,
Dwarf_Op **llbuf, size_t *listlen)
{
Dwarf *dbg = cu->dbg;
/* Check whether we already looked at this list. */
struct loc_s fake = { .addr = block->data };
struct loc_s **found = tfind (&fake, &cu->locs, loc_compare);
if (found != NULL)
{
/* We already saw it. */
*llbuf = (*found)->loc;
*listlen = (*found)->nloc;
return 0;
}
const unsigned char *data = block->data;
const unsigned char *const end_data = data + block->length;
struct loclist *loclist = NULL;
unsigned int n = 0;
/* Decode the opcodes. It is possible in some situations to have a
block of size zero. */
while (data < end_data)
{
struct loclist *newloc;
newloc = (struct loclist *) alloca (sizeof (struct loclist));
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
newloc->next = loclist;
loclist = newloc;
++n;
switch ((newloc->atom = *data++))
{
case DW_OP_addr:
/* Address, depends on address size of CU. */
if (cu->address_size == 4)
{
if (unlikely (data + 4 > end_data))
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
newloc->number = read_4ubyte_unaligned_inc (dbg, data);
}
else
{
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (dbg, data);
}
break;
case DW_OP_deref:
case DW_OP_dup:
case DW_OP_drop:
case DW_OP_over:
case DW_OP_swap:
case DW_OP_rot:
case DW_OP_xderef:
case DW_OP_abs:
case DW_OP_and:
case DW_OP_div:
case DW_OP_minus:
case DW_OP_mod:
case DW_OP_mul:
case DW_OP_neg:
case DW_OP_not:
case DW_OP_or:
case DW_OP_plus:
case DW_OP_shl:
case DW_OP_shr:
case DW_OP_shra:
case DW_OP_xor:
case DW_OP_eq:
case DW_OP_ge:
case DW_OP_gt:
case DW_OP_le:
case DW_OP_lt:
case DW_OP_ne:
case DW_OP_lit0 ... DW_OP_lit31:
case DW_OP_reg0 ... DW_OP_reg31:
case DW_OP_nop:
case DW_OP_push_object_address:
case DW_OP_call_ref:
/* No operand. */
break;
case DW_OP_const1u:
case DW_OP_pick:
case DW_OP_deref_size:
case DW_OP_xderef_size:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *data++;
break;
case DW_OP_const1s:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *((int8_t *) data);
++data;
break;
case DW_OP_const2u:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const2s:
case DW_OP_skip:
case DW_OP_bra:
case DW_OP_call2:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_const4u:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const4s:
case DW_OP_call4:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_const8u:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const8s:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_constu:
case DW_OP_plus_uconst:
case DW_OP_regx:
case DW_OP_piece:
/* XXX Check size. */
get_uleb128 (newloc->number, data);
break;
case DW_OP_consts:
case DW_OP_breg0 ... DW_OP_breg31:
case DW_OP_fbreg:
/* XXX Check size. */
get_sleb128 (newloc->number, data);
break;
case DW_OP_bregx:
/* XXX Check size. */
get_uleb128 (newloc->number, data);
get_sleb128 (newloc->number2, data);
break;
default:
goto invalid;
}
}
if (unlikely (n == 0))
{
/* This is not allowed.
XXX Is it? */
goto invalid;
}
/* Allocate the array. */
Dwarf_Op *result = libdw_alloc (dbg, Dwarf_Op, sizeof (Dwarf_Op), n);
/* Store the result. */
*llbuf = result;
*listlen = n;
do
{
/* We populate the array from the back since the list is
backwards. */
--n;
result[n].atom = loclist->atom;
result[n].number = loclist->number;
result[n].number2 = loclist->number2;
result[n].offset = loclist->offset;
loclist = loclist->next;
}
while (n > 0);
/* Insert a record in the search tree so that we can find it again
later. */
struct loc_s *newp = libdw_alloc (dbg, struct loc_s, sizeof (struct loc_s),
1);
newp->addr = block->data;
newp->loc = result;
newp->nloc = *listlen;
(void) tsearch (newp, &cu->locs, loc_compare);
/* We did it. */
return 0;
}
int
dwarf_getlocation (attr, llbuf, listlen)
Dwarf_Attribute *attr;
Dwarf_Op **llbuf;
size_t *listlen;
{
if (! attr_ok (attr))
return -1;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) != 0)
return -1;
return getlocation (attr->cu, &block, llbuf, listlen);
}
int
dwarf_getlocation_addr (attr, address, llbufs, listlens, maxlocs)
Dwarf_Attribute *attr;
Dwarf_Addr address;
Dwarf_Op **llbufs;
size_t *listlens;
size_t maxlocs;
{
if (! attr_ok (attr))
return -1;
if (llbufs == NULL)
maxlocs = SIZE_MAX;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) == 0)
{
if (maxlocs == 0)
return 0;
if (llbufs != NULL &&
getlocation (attr->cu, &block, &llbufs[0], &listlens[0]) != 0)
return -1;
return listlens[0] == 0 ? 0 : 1;
}
int error = INTUSE(dwarf_errno) ();
if (unlikely (error != DWARF_E_NO_BLOCK))
{
__libdw_seterrno (error);
return -1;
}
/* Must have the form data4 or data8 which act as an offset. */
Dwarf_Word offset;
if (unlikely (INTUSE(dwarf_formudata) (attr, &offset) != 0))
return -1;
const Elf_Data *d = attr->cu->dbg->sectiondata[IDX_debug_loc];
if (unlikely (d == NULL))
{
__libdw_seterrno (DWARF_E_NO_LOCLIST);
return -1;
}
Dwarf_Addr base = (Dwarf_Addr) -1;
unsigned char *readp = d->d_buf + offset;
size_t got = 0;
while (got < maxlocs)
{
if ((unsigned char *) d->d_buf + d->d_size - readp
< attr->cu->address_size * 2)
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
Dwarf_Addr begin;
Dwarf_Addr end;
if (attr->cu->address_size == 8)
{
begin = read_8ubyte_unaligned_inc (attr->cu->dbg, readp);
end = read_8ubyte_unaligned_inc (attr->cu->dbg, readp);
if (begin == (Elf64_Addr) -1l) /* Base address entry. */
{
base = end;
if (unlikely (base == (Dwarf_Addr) -1))
goto invalid;
continue;
}
}
else
{
begin = read_4ubyte_unaligned_inc (attr->cu->dbg, readp);
end = read_4ubyte_unaligned_inc (attr->cu->dbg, readp);
if (begin == (Elf32_Addr) -1) /* Base address entry. */
{
base = end;
continue;
}
}
if (begin == 0 && end == 0) /* End of list entry. */
break;
if ((unsigned char *) d->d_buf + d->d_size - readp < 2)
goto invalid;
/* We have a location expression. */
block.length = read_2ubyte_unaligned_inc (attr->cu->dbg, readp);
block.data = readp;
if ((unsigned char *) d->d_buf + d->d_size - readp
< (ptrdiff_t) block.length)
goto invalid;
readp += block.length;
if (base == (Dwarf_Addr) -1)
{
/* 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. */
Dwarf_Attribute attr_mem;
if (unlikely (INTUSE(dwarf_lowpc) (&cudie, &base) != 0)
&& INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie,
DW_AT_entry_pc,
&attr_mem),
&base) != 0)
{
if (INTUSE(dwarf_errno) () != 0)
return -1;
/* The compiler provided no base address when it should
have. Buggy GCC does this when it used absolute
addresses in the location list and no DW_AT_ranges. */
base = 0;
}
}
if (address >= base + begin && address < base + end)
{
/* This one matches the address. */
if (llbufs != NULL
&& unlikely (getlocation (attr->cu, &block,
&llbufs[got], &listlens[got]) != 0))
return -1;
++got;
}
}
return got;
}
int
dwarf_getsrclines (Dwarf_Die *cudie, Dwarf_Lines **lines, size_t *nlines)
{
if (unlikely (cudie == NULL
|| (INTUSE(dwarf_tag) (cudie) != DW_TAG_compile_unit
&& INTUSE(dwarf_tag) (cudie) != DW_TAG_partial_unit)))
return -1;
int res = -1;
struct linelist *linelist = NULL;
unsigned int nlinelist = 0;
/* If there are a large number of lines don't blow up the stack.
Keep track of the last malloced linelist record and free them
through the next pointer at the end. */
#define MAX_STACK_ALLOC 4096
struct linelist *malloc_linelist = NULL;
/* Get the information if it is not already known. */
struct Dwarf_CU *const cu = cudie->cu;
if (cu->lines == NULL)
{
/* Failsafe mode: no data found. */
cu->lines = (void *) -1l;
cu->files = (void *) -1l;
/* The die must have a statement list associated. */
Dwarf_Attribute stmt_list_mem;
Dwarf_Attribute *stmt_list = INTUSE(dwarf_attr) (cudie, DW_AT_stmt_list,
&stmt_list_mem);
/* Get the offset into the .debug_line section. NB: this call
also checks whether the previous dwarf_attr call failed. */
const unsigned char *lineendp;
const unsigned char *linep
= __libdw_formptr (stmt_list, IDX_debug_line, DWARF_E_NO_DEBUG_LINE,
(unsigned char **) &lineendp, NULL);
if (linep == NULL)
goto out;
/* Get the compilation directory. */
Dwarf_Attribute compdir_attr_mem;
Dwarf_Attribute *compdir_attr = INTUSE(dwarf_attr) (cudie,
DW_AT_comp_dir,
&compdir_attr_mem);
const char *comp_dir = INTUSE(dwarf_formstring) (compdir_attr);
if (unlikely (linep + 4 > lineendp))
{
invalid_data:
__libdw_seterrno (DWARF_E_INVALID_DEBUG_LINE);
goto out;
}
Dwarf *dbg = cu->dbg;
Dwarf_Word unit_length = read_4ubyte_unaligned_inc (dbg, linep);
unsigned int length = 4;
if (unlikely (unit_length == DWARF3_LENGTH_64_BIT))
{
if (unlikely (linep + 8 > lineendp))
goto invalid_data;
unit_length = read_8ubyte_unaligned_inc (dbg, linep);
length = 8;
}
/* Check whether we have enough room in the section. */
if (unit_length < 2 + length + 5 * 1
|| unlikely (linep + unit_length > lineendp))
goto invalid_data;
lineendp = linep + unit_length;
/* The next element of the header is the version identifier. */
uint_fast16_t version = read_2ubyte_unaligned_inc (dbg, linep);
if (unlikely (version < 2) || unlikely (version > 4))
{
__libdw_seterrno (DWARF_E_VERSION);
goto out;
}
/* Next comes the header length. */
Dwarf_Word header_length;
if (length == 4)
header_length = read_4ubyte_unaligned_inc (dbg, linep);
else
header_length = read_8ubyte_unaligned_inc (dbg, linep);
const unsigned char *header_start = linep;
/* Next the minimum instruction length. */
uint_fast8_t minimum_instr_len = *linep++;
/* Next the maximum operations per instruction, in version 4 format. */
uint_fast8_t max_ops_per_instr = 1;
if (version >= 4)
{
if (unlikely (lineendp - linep < 5))
goto invalid_data;
max_ops_per_instr = *linep++;
if (unlikely (max_ops_per_instr == 0))
goto invalid_data;
}
/* Then the flag determining the default value of the is_stmt
register. */
uint_fast8_t default_is_stmt = *linep++;
/* Now the line base. */
int_fast8_t line_base = (int8_t) *linep++;
/* And the line range. */
uint_fast8_t line_range = *linep++;
/* The opcode base. */
uint_fast8_t opcode_base = *linep++;
/* Remember array with the standard opcode length (-1 to account for
the opcode with value zero not being mentioned). */
const uint8_t *standard_opcode_lengths = linep - 1;
if (unlikely (lineendp - linep < opcode_base - 1))
goto invalid_data;
linep += opcode_base - 1;
/* First comes the list of directories. Add the compilation
directory first since the index zero is used for it. */
struct dirlist
{
const char *dir;
size_t len;
struct dirlist *next;
} comp_dir_elem =
{
.dir = comp_dir,
.len = comp_dir ? strlen (comp_dir) : 0,
.next = NULL
};
struct dirlist *dirlist = &comp_dir_elem;
unsigned int ndirlist = 1;
// XXX Directly construct array to conserve memory?
while (*linep != 0)
{
struct dirlist *new_dir =
(struct dirlist *) alloca (sizeof (*new_dir));
new_dir->dir = (char *) linep;
uint8_t *endp = memchr (linep, '\0', lineendp - linep);
if (endp == NULL)
goto invalid_data;
new_dir->len = endp - linep;
new_dir->next = dirlist;
dirlist = new_dir;
++ndirlist;
linep = endp + 1;
}
/* Skip the final NUL byte. */
++linep;
/* Rearrange the list in array form. */
struct dirlist **dirarray
= (struct dirlist **) alloca (ndirlist * sizeof (*dirarray));
for (unsigned int n = ndirlist; n-- > 0; dirlist = dirlist->next)
dirarray[n] = dirlist;
/* Now read the files. */
struct filelist null_file =
{
.info =
{
.name = "???",
.mtime = 0,
.length = 0
},
.next = NULL
};
struct filelist *filelist = &null_file;
unsigned int nfilelist = 1;
if (unlikely (linep >= lineendp))
goto invalid_data;
while (*linep != 0)
{
struct filelist *new_file =
(struct filelist *) alloca (sizeof (*new_file));
/* First comes the file name. */
char *fname = (char *) linep;
uint8_t *endp = memchr (fname, '\0', lineendp - linep);
if (endp == NULL)
goto invalid_data;
size_t fnamelen = endp - (uint8_t *) fname;
linep = endp + 1;
/* Then the index. */
Dwarf_Word diridx;
get_uleb128 (diridx, linep);
if (unlikely (diridx >= ndirlist))
{
__libdw_seterrno (DWARF_E_INVALID_DIR_IDX);
goto out;
}
if (*fname == '/')
/* It's an absolute path. */
new_file->info.name = fname;
else
{
new_file->info.name = libdw_alloc (dbg, char, 1,
dirarray[diridx]->len + 1
+ fnamelen + 1);
char *cp = new_file->info.name;
if (dirarray[diridx]->dir != NULL)
{
/* This value could be NULL in case the DW_AT_comp_dir
was not present. We cannot do much in this case.
The easiest thing is to convert the path in an
absolute path. */
cp = stpcpy (cp, dirarray[diridx]->dir);
}
*cp++ = '/';
strcpy (cp, fname);
assert (strlen (new_file->info.name)
< dirarray[diridx]->len + 1 + fnamelen + 1);
}
/* Next comes the modification time. */
get_uleb128 (new_file->info.mtime, linep);
/* Finally the length of the file. */
get_uleb128 (new_file->info.length, linep);
new_file->next = filelist;
filelist = new_file;
++nfilelist;
}
/* Skip the final NUL byte. */
++linep;
/* Consistency check. */
if (unlikely (linep != header_start + header_length))
{
__libdw_seterrno (DWARF_E_INVALID_DWARF);
goto out;
}
/* We are about to process the statement program. Initialize the
state machine registers (see 6.2.2 in the v2.1 specification). */
Dwarf_Word addr = 0;
unsigned int op_index = 0;
unsigned int file = 1;
int line = 1;
unsigned int column = 0;
uint_fast8_t is_stmt = default_is_stmt;
bool basic_block = false;
bool prologue_end = false;
bool epilogue_begin = false;
unsigned int isa = 0;
unsigned int discriminator = 0;
/* Apply the "operation advance" from a special opcode
or DW_LNS_advance_pc (as per DWARF4 6.2.5.1). */
inline void advance_pc (unsigned int op_advance)
{
addr += minimum_instr_len * ((op_index + op_advance)
/ max_ops_per_instr);
op_index = (op_index + op_advance) % max_ops_per_instr;
}
int
dwarf_formudata (Dwarf_Attribute *attr, Dwarf_Word *return_uval)
{
if (attr == NULL)
return -1;
const unsigned char *datap = attr->valp;
const unsigned char *endp = attr->cu->endp;
switch (attr->form)
{
case DW_FORM_data1:
if (datap + 1 > endp)
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
*return_uval = *attr->valp;
break;
case DW_FORM_data2:
if (datap + 2 > endp)
goto invalid;
*return_uval = read_2ubyte_unaligned (attr->cu->dbg, attr->valp);
break;
case DW_FORM_data4:
case DW_FORM_data8:
case DW_FORM_sec_offset:
/* Before DWARF4 data4 and data8 are pure constants unless the
attribute also allows offsets (*ptr classes), since DWARF4
they are always just constants (start_scope is special though,
since it only could express a rangelist since DWARF4). */
if (attr->form == DW_FORM_sec_offset
|| (attr->cu->version < 4 && attr->code != DW_AT_start_scope))
{
switch (attr->code)
{
case DW_AT_data_member_location:
case DW_AT_frame_base:
case DW_AT_location:
case DW_AT_return_addr:
case DW_AT_segment:
case DW_AT_static_link:
case DW_AT_string_length:
case DW_AT_use_location:
case DW_AT_vtable_elem_location:
/* loclistptr */
if (__libdw_formptr (attr, IDX_debug_loc,
DWARF_E_NO_LOCLIST, NULL,
return_uval) == NULL)
return -1;
break;
case DW_AT_macro_info:
/* macptr into .debug_macinfo */
if (__libdw_formptr (attr, IDX_debug_macinfo,
DWARF_E_NO_ENTRY, NULL,
return_uval) == NULL)
return -1;
break;
case DW_AT_GNU_macros:
/* macptr into .debug_macro */
if (__libdw_formptr (attr, IDX_debug_macro,
DWARF_E_NO_ENTRY, NULL,
return_uval) == NULL)
return -1;
break;
case DW_AT_ranges:
case DW_AT_start_scope:
/* rangelistptr */
if (__libdw_formptr (attr, IDX_debug_ranges,
DWARF_E_NO_DEBUG_RANGES, NULL,
return_uval) == NULL)
return -1;
break;
case DW_AT_stmt_list:
/* lineptr */
if (__libdw_formptr (attr, IDX_debug_line,
DWARF_E_NO_DEBUG_LINE, NULL,
return_uval) == NULL)
return -1;
break;
default:
/* sec_offset can only be used by one of the above attrs. */
if (attr->form == DW_FORM_sec_offset)
{
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
/* Not one of the special attributes, just a constant. */
if (__libdw_read_address (attr->cu->dbg, cu_sec_idx (attr->cu),
attr->valp,
attr->form == DW_FORM_data4 ? 4 : 8,
return_uval))
return -1;
break;
}
}
else
{
/* We are dealing with a constant data4 or data8. */
if (__libdw_read_address (attr->cu->dbg, cu_sec_idx (attr->cu),
attr->valp,
attr->form == DW_FORM_data4 ? 4 : 8,
return_uval))
return -1;
}
break;
case DW_FORM_sdata:
if (datap + 1 > endp)
goto invalid;
get_sleb128 (*return_uval, datap, endp);
break;
case DW_FORM_udata:
if (datap + 1 > endp)
goto invalid;
get_uleb128 (*return_uval, datap, endp);
break;
default:
__libdw_seterrno (DWARF_E_NO_CONSTANT);
return -1;
}
return 0;
}
int
internal_function
__libdw_formref (Dwarf_Attribute *attr, Dwarf_Off *return_offset)
{
const unsigned char *datap = attr->valp;
const unsigned char *endp = attr->cu->endp;
if (attr->valp == NULL)
{
__libdw_seterrno (DWARF_E_INVALID_REFERENCE);
return -1;
}
switch (attr->form)
{
case DW_FORM_ref1:
if (datap + 1 > endp)
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
*return_offset = *attr->valp;
break;
case DW_FORM_ref2:
if (datap + 2 > endp)
goto invalid;
*return_offset = read_2ubyte_unaligned (attr->cu->dbg, attr->valp);
break;
case DW_FORM_ref4:
if (datap + 4 > endp)
goto invalid;
*return_offset = read_4ubyte_unaligned (attr->cu->dbg, attr->valp);
break;
case DW_FORM_ref8:
if (datap + 8 > endp)
goto invalid;
*return_offset = read_8ubyte_unaligned (attr->cu->dbg, attr->valp);
break;
case DW_FORM_ref_udata:
if (datap + 1 > endp)
goto invalid;
get_uleb128 (*return_offset, datap, endp);
break;
case DW_FORM_ref_addr:
case DW_FORM_ref_sig8:
case DW_FORM_GNU_ref_alt:
/* These aren't handled by dwarf_formref, only by dwarf_formref_die. */
__libdw_seterrno (DWARF_E_INVALID_REFERENCE);
return -1;
default:
__libdw_seterrno (DWARF_E_NO_REFERENCE);
return -1;
}
return 0;
}
/* Unwind to previous to frame. Returns 0 if successful, negative
* number in case of an error. */
int
unwind(struct unwind_frame_info *frame, int is_ehframe)
{
#define FRAME_REG(r, t) (((t *)frame)[reg_info[r].offs])
const u32 *fde = NULL, *cie = NULL;
const u8 *ptr = NULL, *end = NULL;
unsigned long startLoc = 0, endLoc = 0, cfa;
unsigned i;
signed ptrType = -1;
uleb128_t retAddrReg = 0;
// struct unwind_table *table;
void *unwind_table;
struct local_unwind_table *table;
struct unwind_state state;
u64 reg_ptr = 0;
if (UNW_PC(frame) == 0)
return -EINVAL;
if ((table = find_table(UNW_PC(frame)))) {
// unsigned long tableSize = unwind_table_size;
unsigned long tableSize = table->size;
unwind_table = table->address;
for (fde = unwind_table;
tableSize > sizeof(*fde) && tableSize - sizeof(*fde) >= *fde;
tableSize -= sizeof(*fde) + *fde,
fde += 1 + *fde / sizeof(*fde)) {
if (!*fde || (*fde & (sizeof(*fde) - 1)))
break;
if (is_ehframe && !fde[1])
continue; /* this is a CIE */
else if (fde[1] == 0xffffffff)
continue; /* this is a CIE */
if ((fde[1] & (sizeof(*fde) - 1))
|| fde[1] > (unsigned long)(fde + 1)
- (unsigned long)unwind_table)
continue; /* this is not a valid FDE */
if (is_ehframe)
cie = fde + 1 - fde[1] / sizeof(*fde);
else
cie = unwind_table + fde[1];
if (*cie <= sizeof(*cie) + 4
|| *cie >= fde[1] - sizeof(*fde)
|| (*cie & (sizeof(*cie) - 1))
|| (cie[1] != 0xffffffff && cie[1])
|| (ptrType = fde_pointer_type(cie)) < 0) {
cie = NULL; /* this is not a (valid) CIE */
continue;
}
ptr = (const u8 *)(fde + 2);
startLoc = read_pointer(&ptr,
(const u8 *)(fde + 1) + *fde,
ptrType);
endLoc = startLoc
+ read_pointer(&ptr,
(const u8 *)(fde + 1) + *fde,
ptrType & DW_EH_PE_indirect
? ptrType
: ptrType & (DW_EH_PE_FORM|DW_EH_PE_signed));
if (UNW_PC(frame) >= startLoc && UNW_PC(frame) < endLoc)
break;
cie = NULL;
}
}
if (cie != NULL) {
memset(&state, 0, sizeof(state));
state.cieEnd = ptr; /* keep here temporarily */
ptr = (const u8 *)(cie + 2);
end = (const u8 *)(cie + 1) + *cie;
if ((state.version = *ptr) != 1)
cie = NULL; /* unsupported version */
else if (*++ptr) {
/* check if augmentation size is first (and thus present) */
if (*ptr == 'z') {
/* check for ignorable (or already handled)
* nul-terminated augmentation string */
while (++ptr < end && *ptr)
if (strchr("LPR", *ptr) == NULL)
break;
}
if (ptr >= end || *ptr)
cie = NULL;
}
++ptr;
}
if (cie != NULL) {
/* get code aligment factor */
state.codeAlign = get_uleb128(&ptr, end);
/* get data aligment factor */
state.dataAlign = get_sleb128(&ptr, end);
if (state.codeAlign == 0 || state.dataAlign == 0 || ptr >= end)
cie = NULL;
else {
retAddrReg = state.version <= 1 ? *ptr++ : get_uleb128(&ptr, end);
/* skip augmentation */
if (((const char *)(cie + 2))[1] == 'z')
ptr += get_uleb128(&ptr, end);
if (ptr > end
|| retAddrReg >= ARRAY_SIZE(reg_info)
|| REG_INVALID(retAddrReg)
|| reg_info[retAddrReg].width != sizeof(unsigned long))
cie = NULL;
}
}
if (cie != NULL) {
state.cieStart = ptr;
ptr = state.cieEnd;
state.cieEnd = end;
end = (const u8 *)(fde + 1) + *fde;
/* skip augmentation */
if (((const char *)(cie + 2))[1] == 'z') {
uleb128_t augSize = get_uleb128(&ptr, end);
if ((ptr += augSize) > end)
fde = NULL;
}
}
if (cie == NULL || fde == NULL)
return -ENXIO;
state.org = startLoc;
memcpy(&state.cfa, &badCFA, sizeof(state.cfa));
/* process instructions */
if (!processCFI(ptr, end, UNW_PC(frame), ptrType, &state)
|| state.loc > endLoc
|| state.regs[retAddrReg].where == Nowhere
|| state.cfa.reg >= ARRAY_SIZE(reg_info)
|| reg_info[state.cfa.reg].width != sizeof(unsigned long)
|| state.cfa.offs % sizeof(unsigned long)) {
return -EIO;
}
/* update frame */
cfa = FRAME_REG(state.cfa.reg, unsigned long) + state.cfa.offs;
startLoc = min((unsigned long)UNW_SP(frame), cfa);
endLoc = max((unsigned long)UNW_SP(frame), cfa);
if (STACK_LIMIT(startLoc) != STACK_LIMIT(endLoc)) {
startLoc = min(STACK_LIMIT(cfa), cfa);
endLoc = max(STACK_LIMIT(cfa), cfa);
}
#ifndef CONFIG_64BIT
# define CASES CASE(8); CASE(16); CASE(32)
#else
# define CASES CASE(8); CASE(16); CASE(32); CASE(64)
#endif
for (i = 0; i < ARRAY_SIZE(state.regs); ++i) {
if (REG_INVALID(i)) {
if (state.regs[i].where == Nowhere)
continue;
return -EIO;
}
switch(state.regs[i].where) {
default:
break;
case Register:
if (state.regs[i].value >= ARRAY_SIZE(reg_info)
|| REG_INVALID(state.regs[i].value)
|| reg_info[i].width > reg_info[state.regs[i].value].width){
return -EIO;
}
switch(reg_info[state.regs[i].value].width) {
#define CASE(n) \
case sizeof(u##n): \
state.regs[i].value = FRAME_REG(state.regs[i].value, \
const u##n); \
break
CASES;
#undef CASE
default:
return -EIO;
}
break;
}
}
for (i = 0; i < ARRAY_SIZE(state.regs); ++i) {
if (REG_INVALID(i))
continue;
switch(state.regs[i].where) {
case Nowhere:
if (reg_info[i].width != sizeof(UNW_SP(frame))
|| &FRAME_REG(i, __typeof__(UNW_SP(frame)))
!= &UNW_SP(frame))
continue;
UNW_SP(frame) = cfa;
break;
case Register:
switch(reg_info[i].width) {
#define CASE(n) case sizeof(u##n): \
FRAME_REG(i, u##n) = state.regs[i].value; \
break
CASES;
#undef CASE
default:
return -EIO;
}
break;
case Value:
if (reg_info[i].width != sizeof(unsigned long)){
return -EIO;}
FRAME_REG(i, unsigned long) = cfa + state.regs[i].value
* state.dataAlign;
break;
case Memory: {
unsigned long addr = cfa + state.regs[i].value
* state.dataAlign;
if ((state.regs[i].value * state.dataAlign)
% sizeof(unsigned long)
|| addr < startLoc
|| addr + sizeof(unsigned long) < addr
|| addr + sizeof(unsigned long) > endLoc){
return -EIO;}
switch(reg_info[i].width) {
#define CASE(n) case sizeof(u##n): \
readmem(addr, KVADDR, ®_ptr,sizeof(u##n), "register", RETURN_ON_ERROR|QUIET); \
FRAME_REG(i, u##n) = (u##n)reg_ptr;\
break
CASES;
#undef CASE
default:
return -EIO;
}
}
break;
}
}
return 0;
#undef CASES
#undef FRAME_REG
}
static int processCFI(const u8 *start,
const u8 *end,
unsigned long targetLoc,
signed ptrType,
struct unwind_state *state)
{
union {
const u8 *p8;
const u16 *p16;
const u32 *p32;
} ptr;
int result = 1;
if (start != state->cieStart) {
state->loc = state->org;
result = processCFI(state->cieStart, state->cieEnd, 0, ptrType, state);
if (targetLoc == 0 && state->label == NULL)
return result;
}
for (ptr.p8 = start; result && ptr.p8 < end; ) {
switch(*ptr.p8 >> 6) {
uleb128_t value;
case 0:
switch(*ptr.p8++) {
case DW_CFA_nop:
break;
case DW_CFA_set_loc:
if ((state->loc = read_pointer(&ptr.p8, end,
ptrType)) == 0)
result = 0;
break;
case DW_CFA_advance_loc1:
result = ptr.p8 < end && advance_loc(*ptr.p8++, state);
break;
case DW_CFA_advance_loc2:
result = ptr.p8 <= end + 2
&& advance_loc(*ptr.p16++, state);
break;
case DW_CFA_advance_loc4:
result = ptr.p8 <= end + 4
&& advance_loc(*ptr.p32++, state);
break;
case DW_CFA_offset_extended:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Memory,
get_uleb128(&ptr.p8, end), state);
break;
case DW_CFA_val_offset:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Value,
get_uleb128(&ptr.p8, end), state);
break;
case DW_CFA_offset_extended_sf:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Memory,
get_sleb128(&ptr.p8, end), state);
break;
case DW_CFA_val_offset_sf:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Value,
get_sleb128(&ptr.p8, end), state);
break;
case DW_CFA_restore_extended:
case DW_CFA_undefined:
case DW_CFA_same_value:
set_rule(get_uleb128(&ptr.p8, end), Nowhere, 0, state);
break;
case DW_CFA_register:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Register,
get_uleb128(&ptr.p8, end), state);
break;
case DW_CFA_remember_state:
if (ptr.p8 == state->label) {
state->label = NULL;
return 1;
}
if (state->stackDepth >= MAX_STACK_DEPTH)
return 0;
state->stack[state->stackDepth++] = ptr.p8;
break;
case DW_CFA_restore_state:
if (state->stackDepth) {
const uleb128_t loc = state->loc;
const u8 *label = state->label;
state->label = state->stack[state->stackDepth - 1];
memcpy(&state->cfa, &badCFA, sizeof(state->cfa));
memset(state->regs, 0, sizeof(state->regs));
state->stackDepth = 0;
result = processCFI(start, end, 0, ptrType, state);
state->loc = loc;
state->label = label;
} else
return 0;
break;
case DW_CFA_def_cfa:
state->cfa.reg = get_uleb128(&ptr.p8, end);
/*nobreak*/
case DW_CFA_def_cfa_offset:
state->cfa.offs = get_uleb128(&ptr.p8, end);
break;
case DW_CFA_def_cfa_sf:
state->cfa.reg = get_uleb128(&ptr.p8, end);
/*nobreak*/
case DW_CFA_def_cfa_offset_sf:
state->cfa.offs = get_sleb128(&ptr.p8, end)
* state->dataAlign;
break;
case DW_CFA_def_cfa_register:
state->cfa.reg = get_uleb128(&ptr.p8, end);
break;
/*todo case DW_CFA_def_cfa_expression: */
/*todo case DW_CFA_expression: */
/*todo case DW_CFA_val_expression: */
case DW_CFA_GNU_args_size:
get_uleb128(&ptr.p8, end);
break;
case DW_CFA_GNU_negative_offset_extended:
value = get_uleb128(&ptr.p8, end);
set_rule(value, Memory, (uleb128_t)0 -
get_uleb128(&ptr.p8, end), state);
break;
case DW_CFA_GNU_window_save:
default:
result = 0;
break;
}
break;
case 1:
result = advance_loc(*ptr.p8++ & 0x3f, state);
break;
case 2:
value = *ptr.p8++ & 0x3f;
set_rule(value, Memory, get_uleb128(&ptr.p8, end),
state);
break;
case 3:
set_rule(*ptr.p8++ & 0x3f, Nowhere, 0, state);
break;
}
if (ptr.p8 > end)
result = 0;
if (result && targetLoc != 0 && targetLoc < state->loc)
return 1;
}
return result
&& ptr.p8 == end
&& (targetLoc == 0
|| (/*todo While in theory this should apply, gcc in practice omits
everything past the function prolog, and hence the location
never reaches the end of the function.
targetLoc < state->loc &&*/ state->label == NULL));
}
static unsigned long read_pointer(const u8 **pLoc,
const void *end,
signed ptrType)
{
unsigned long value = 0;
union {
const u8 *p8;
const u16 *p16u;
const s16 *p16s;
const u32 *p32u;
const s32 *p32s;
const unsigned long *pul;
} ptr;
if (ptrType < 0 || ptrType == DW_EH_PE_omit)
return 0;
ptr.p8 = *pLoc;
switch(ptrType & DW_EH_PE_FORM) {
case DW_EH_PE_data2:
if (end < (const void *)(ptr.p16u + 1))
return 0;
if(ptrType & DW_EH_PE_signed)
value = get_unaligned(ptr.p16s++);
else
value = get_unaligned(ptr.p16u++);
break;
case DW_EH_PE_data4:
#ifdef CONFIG_64BIT
if (end < (const void *)(ptr.p32u + 1))
return 0;
if(ptrType & DW_EH_PE_signed)
value = get_unaligned(ptr.p32s++);
else
value = get_unaligned(ptr.p32u++);
break;
case DW_EH_PE_data8:
BUILD_BUG_ON(sizeof(u64) != sizeof(value));
#else
BUILD_BUG_ON(sizeof(u32) != sizeof(value));
#endif
case DW_EH_PE_native:
if (end < (const void *)(ptr.pul + 1))
return 0;
value = get_unaligned(ptr.pul++);
break;
case DW_EH_PE_leb128:
BUILD_BUG_ON(sizeof(uleb128_t) > sizeof(value));
value = ptrType & DW_EH_PE_signed
? get_sleb128(&ptr.p8, end)
: get_uleb128(&ptr.p8, end);
if ((const void *)ptr.p8 > end)
return 0;
break;
default:
return 0;
}
switch(ptrType & DW_EH_PE_ADJUST) {
case DW_EH_PE_abs:
break;
case DW_EH_PE_pcrel:
value += (unsigned long)*pLoc;
break;
default:
return 0;
}
/* TBD
if ((ptrType & DW_EH_PE_indirect)
&& __get_user(value, (unsigned long *)value))
return 0;
*/
*pLoc = ptr.p8;
return value;
}
size_t
internal_function
__libdw_form_val_compute_len (Dwarf *dbg, struct Dwarf_CU *cu,
unsigned int form, const unsigned char *valp)
{
const unsigned char *saved;
Dwarf_Word u128;
size_t result;
/* NB: This doesn't cover constant form lengths, which are
already handled by the inlined __libdw_form_val_len. */
switch (form)
{
case DW_FORM_addr:
result = cu->address_size;
break;
case DW_FORM_ref_addr:
result = cu->version == 2 ? cu->address_size : cu->offset_size;
break;
case DW_FORM_strp:
case DW_FORM_sec_offset:
case DW_FORM_GNU_ref_alt:
case DW_FORM_GNU_strp_alt:
result = cu->offset_size;
break;
case DW_FORM_block1:
result = *valp + 1;
break;
case DW_FORM_block2:
result = read_2ubyte_unaligned (dbg, valp) + 2;
break;
case DW_FORM_block4:
result = read_4ubyte_unaligned (dbg, valp) + 4;
break;
case DW_FORM_block:
case DW_FORM_exprloc:
saved = valp;
get_uleb128 (u128, valp);
result = u128 + (valp - saved);
break;
case DW_FORM_string:
result = strlen ((char *) valp) + 1;
break;
case DW_FORM_sdata:
case DW_FORM_udata:
case DW_FORM_ref_udata:
saved = valp;
get_uleb128 (u128, valp);
result = valp - saved;
break;
case DW_FORM_indirect:
saved = valp;
get_uleb128 (u128, valp);
// XXX Is this really correct?
result = __libdw_form_val_len (dbg, cu, u128, valp);
if (result != (size_t) -1)
result += valp - saved;
break;
default:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
result = (size_t) -1l;
break;
}
return result;
}