blob: 0021e222b79f107aadc14b0c8dfd1e176d459e45 [file] [log] [blame]
/* Get abbreviation at given offset.
Copyright (C) 2003, 2004 Red Hat, Inc.
Written by Ulrich Drepper <drepper@redhat.com>, 2003.
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 <assert.h>
#include <dwarf.h>
#include "libdwP.h"
Dwarf_Abbrev *
internal_function_def
__libdw_getabbrev (dbg, cu, offset, lengthp, result)
Dwarf *dbg;
struct Dwarf_CU *cu;
Dwarf_Off offset;
size_t *lengthp;
Dwarf_Abbrev *result;
{
/* Don't fail if there is not .debug_abbrev section. */
if (dbg->sectiondata[IDX_debug_abbrev] == NULL)
return NULL;
unsigned char *abbrevp
= (unsigned char *) dbg->sectiondata[IDX_debug_abbrev]->d_buf + offset;
if (*abbrevp == '\0')
/* We are past the last entry. */
return NULL;
/* 7.5.3 Abbreviations Tables
[...] Each declaration begins with an unsigned LEB128 number
representing the abbreviation code itself. [...] The
abbreviation code is followed by another unsigned LEB128
number that encodes the entry's tag. [...]
[...] Following the tag encoding is a 1-byte value that
determines whether a debugging information entry using this
abbreviation has child entries or not. [...]
[...] Finally, the child encoding is followed by a series of
attribute specifications. Each attribute specification
consists of two parts. The first part is an unsigned LEB128
number representing the attribute's name. The second part is
an unsigned LEB128 number representing the attribute's form. */
unsigned char *start_abbrevp = abbrevp;
unsigned int code;
get_uleb128 (code, abbrevp);
/* Check whether this code is already in the hash table. */
bool foundit = false;
Dwarf_Abbrev *abb = NULL;
if (cu == NULL
|| (abb = Dwarf_Abbrev_Hash_find (&cu->abbrev_hash, code, NULL)) == NULL)
{
if (result == NULL)
abb = libdw_typed_alloc (dbg, Dwarf_Abbrev);
else
abb = result;
}
else
{
foundit = true;
assert (abb->offset == offset);
/* If the caller doesn't need the length we are done. */
if (lengthp == NULL)
goto out;
}
/* If there is already a value in the hash table we are going to
overwrite its content. This must not be a problem, since the
content better be the same. */
abb->code = code;
get_uleb128 (abb->tag, abbrevp);
abb->has_children = *abbrevp++ == DW_CHILDREN_yes;
abb->attrp = abbrevp;
abb->offset = offset;
/* Skip over all the attributes and count them while doing so. */
abb->attrcnt = 0;
unsigned int attrname;
unsigned int attrform;
do
{
get_uleb128 (attrname, abbrevp);
get_uleb128 (attrform, abbrevp);
}
while (attrname != 0 && attrform != 0 && ++abb->attrcnt);
/* Return the length to the caller if she asked for it. */
if (lengthp != NULL)
*lengthp = abbrevp - start_abbrevp;
/* Add the entry to the hash table. */
if (cu != NULL && ! foundit)
(void) Dwarf_Abbrev_Hash_insert (&cu->abbrev_hash, abb->code, abb);
out:
return abb;
}
Dwarf_Abbrev *
dwarf_getabbrev (die, offset, lengthp)
Dwarf_Die *die;
Dwarf_Off offset;
size_t *lengthp;
{
return __libdw_getabbrev (die->cu->dbg, die->cu,
die->cu->orig_abbrev_offset + offset, lengthp,
NULL);
}