dwarf_global.c revision 07dc1947c362e187fb955d283b692f8769dd5def
/*
Copyright (C) 2000-2005 Silicon Graphics, Inc. All Rights Reserved.
Portions Copyright (C) 2007-2010 David Anderson. All Rights Reserved.
This program is free software; you can redistribute it and/or modify it
under the terms of version 2.1 of the GNU Lesser General Public License
as published by the Free Software Foundation.
This program is distributed in the hope that it would be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Further, this software is distributed without any warranty that it is
free of the rightful claim of any third person regarding infringement
or the like. Any license provided herein, whether implied or
otherwise, applies only to this software file. Patent licenses, if
any, provided herein do not apply to combinations of this program with
other software, or any other product whatsoever.
You should have received a copy of the GNU Lesser General Public
License along with this program; if not, write the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston MA 02110-1301,
USA.
Contact information: Silicon Graphics, Inc., 1500 Crittenden Lane,
Mountain View, CA 94043, or:
http://www.sgi.com
For further information regarding this notice, see:
http://oss.sgi.com/projects/GenInfo/NoticeExplan
*/
/* The address of the Free Software Foundation is
Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
Boston, MA 02110-1301, USA.
SGI has moved from the Crittenden Lane address.
*/
#include "config.h"
#include "dwarf_incl.h"
#include <stdio.h>
#include "dwarf_global.h"
#ifdef __sgi /* __sgi should only be defined for IRIX/MIPS. */
/* The 'fixup' here intended for IRIX targets only.
With a 2+GB Elf64 IRIX executable (under 4GB in size),
some DIE offsets wrongly
got the 32bit upper bit sign extended. For the cu-header
offset in the .debug_pubnames section and in the
.debug_aranges section.
the 'varp' here is a pointer to an offset into .debug_info.
We fix up the offset here if it seems advisable..
As of June 2005 we have identified a series of mistakes
in ldx64 that can cause this (64 bit values getting passed
thru 32-bit signed knothole).
*/
void
_dwarf_fix_up_offset_irix(Dwarf_Debug dbg,
Dwarf_Unsigned * varp, char *caller_site_name)
{
Dwarf_Unsigned var = *varp;
#define UPPER33 0xffffffff80000000LL
#define LOWER32 0xffffffffLL
/* Restrict the hack to the known case. Upper 32 bits erroneously
sign extended from lower 32 upper bit. */
if ((var & UPPER33) == UPPER33) {
var &= LOWER32;
/* Apply the fix. Dreadful hack. */
*varp = var;
}
#undef UPPER33
#undef LOWER32
return;
}
#endif
int
dwarf_get_globals(Dwarf_Debug dbg,
Dwarf_Global ** globals,
Dwarf_Signed * return_count, Dwarf_Error * error)
{
int res = _dwarf_load_section(dbg, &dbg->de_debug_pubnames,error);
if (res != DW_DLV_OK) {
return res;
}
return _dwarf_internal_get_pubnames_like_data(dbg,
dbg->de_debug_pubnames.dss_data,
dbg->de_debug_pubnames.dss_size,
globals,
return_count,
error,
DW_DLA_GLOBAL_CONTEXT,
DW_DLA_GLOBAL,
DW_DLE_PUBNAMES_LENGTH_BAD,
DW_DLE_PUBNAMES_VERSION_ERROR);
}
/* Deallocating fully requires deallocating the list
and all entries. But some internal data is
not exposed, so we need a function with internal knowledge.
*/
void
dwarf_globals_dealloc(Dwarf_Debug dbg, Dwarf_Global * dwgl,
Dwarf_Signed count)
{
_dwarf_internal_globals_dealloc(dbg, dwgl,
count,
DW_DLA_GLOBAL_CONTEXT,
DW_DLA_GLOBAL, DW_DLA_LIST);
return;
}
void
_dwarf_internal_globals_dealloc(Dwarf_Debug dbg, Dwarf_Global * dwgl,
Dwarf_Signed count,
int context_code,
int global_code, int list_code)
{
Dwarf_Signed i;
struct Dwarf_Global_Context_s *gcp = 0;
struct Dwarf_Global_Context_s *lastgcp = 0;
for (i = 0; i < count; i++) {
Dwarf_Global dgb = dwgl[i];
gcp = dgb->gl_context;
if (lastgcp != gcp) {
lastgcp = gcp;
dwarf_dealloc(dbg, gcp, context_code);
}
dwarf_dealloc(dbg, dgb, global_code);
}
dwarf_dealloc(dbg, dwgl, list_code);
return;
}
/* Sweeps the complete section.
*/
int
_dwarf_internal_get_pubnames_like_data(Dwarf_Debug dbg,
Dwarf_Small * section_data_ptr,
Dwarf_Unsigned section_length,
Dwarf_Global ** globals,
Dwarf_Signed * return_count,
Dwarf_Error * error,
int context_code,
int global_code,
int length_err_num,
int version_err_num)
{
Dwarf_Small *pubnames_like_ptr = 0;
/* Points to the context for the current set of global names, and
contains information to identify the compilation-unit that the
set refers to. */
Dwarf_Global_Context pubnames_context = 0;
Dwarf_Half version = 0;
/*
Offset from the start of compilation-unit for the current
global. */
Dwarf_Off die_offset_in_cu = 0;
Dwarf_Unsigned global_count = 0;
/* Points to the current global read. */
Dwarf_Global global = 0;
/* Used to chain the Dwarf_Global_s structs for creating contiguous
list of pointers to the structs. */
Dwarf_Chain curr_chain = 0;
Dwarf_Chain prev_chain = 0;
Dwarf_Chain head_chain = 0;
/* Points to contiguous block of Dwarf_Global's to be returned. */
Dwarf_Global *ret_globals = 0;
/* Temporary counter. */
Dwarf_Unsigned i = 0;
if (dbg == NULL) {
_dwarf_error(NULL, error, DW_DLE_DBG_NULL);
return (DW_DLV_ERROR);
}
/* We will eventually need the .debug_info data. Load it now. */
if (!dbg->de_debug_info.dss_data) {
int res = _dwarf_load_debug_info(dbg, error);
if (res != DW_DLV_OK) {
return res;
}
}
if (section_data_ptr == NULL) {
return (DW_DLV_NO_ENTRY);
}
pubnames_like_ptr = section_data_ptr;
do {
Dwarf_Unsigned length = 0;
int local_extension_size = 0;
int local_length_size = 0;
/* Some compilers emit padding at the end of each cu's area.
pubnames_ptr_past_end_cu records the true area end for this
cu's data. Essentially the length in the header and the 0
terminator of the data are redundant information. The
dwarf2/3 spec does not mention what to do if the length is
past the 0 terminator. So we take any bytes left after the 0
as padding and ignore them. */
Dwarf_Small *pubnames_ptr_past_end_cu = 0;
pubnames_context = (Dwarf_Global_Context)
_dwarf_get_alloc(dbg, context_code, 1);
if (pubnames_context == NULL) {
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return (DW_DLV_ERROR);
}
/* READ_AREA_LENGTH updates pubnames_like_ptr for consumed
bytes. */
READ_AREA_LENGTH(dbg, length, Dwarf_Unsigned,
pubnames_like_ptr, local_length_size,
local_extension_size);
pubnames_context->pu_length_size = local_length_size;
pubnames_context->pu_extension_size = local_extension_size;
pubnames_context->pu_dbg = dbg;
pubnames_ptr_past_end_cu = pubnames_like_ptr + length;
READ_UNALIGNED(dbg, version, Dwarf_Half,
pubnames_like_ptr, sizeof(Dwarf_Half));
pubnames_like_ptr += sizeof(Dwarf_Half);
if (version != CURRENT_VERSION_STAMP) {
_dwarf_error(dbg, error, version_err_num);
return (DW_DLV_ERROR);
}
/* Offset of CU header in debug section. */
READ_UNALIGNED(dbg, pubnames_context->pu_offset_of_cu_header,
Dwarf_Off, pubnames_like_ptr,
pubnames_context->pu_length_size);
pubnames_like_ptr += pubnames_context->pu_length_size;
FIX_UP_OFFSET_IRIX_BUG(dbg,
pubnames_context->pu_offset_of_cu_header,
"pubnames cu header offset");
READ_UNALIGNED(dbg, pubnames_context->pu_info_length,
Dwarf_Unsigned, pubnames_like_ptr,
pubnames_context->pu_length_size);
pubnames_like_ptr += pubnames_context->pu_length_size;
if (pubnames_like_ptr > (section_data_ptr + section_length)) {
_dwarf_error(dbg, error, length_err_num);
return (DW_DLV_ERROR);
}
/* Read initial offset (of DIE within CU) of a pubname, final
entry is not a pair, just a zero offset. */
READ_UNALIGNED(dbg, die_offset_in_cu, Dwarf_Off,
pubnames_like_ptr,
pubnames_context->pu_length_size);
pubnames_like_ptr += pubnames_context->pu_length_size;
FIX_UP_OFFSET_IRIX_BUG(dbg,
die_offset_in_cu, "offset of die in cu");
/* Loop thru pairs. DIE off with CU followed by string. */
while (die_offset_in_cu != 0) {
/* Already read offset, pubnames_like_ptr now points to the
string. */
global =
(Dwarf_Global) _dwarf_get_alloc(dbg, global_code, 1);
if (global == NULL) {
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return (DW_DLV_ERROR);
}
global_count++;
global->gl_context = pubnames_context;
global->gl_named_die_offset_within_cu = die_offset_in_cu;
global->gl_name = pubnames_like_ptr;
pubnames_like_ptr = pubnames_like_ptr +
strlen((char *) pubnames_like_ptr) + 1;
/* finish off current entry chain */
curr_chain =
(Dwarf_Chain) _dwarf_get_alloc(dbg, DW_DLA_CHAIN, 1);
if (curr_chain == NULL) {
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return (DW_DLV_ERROR);
}
/* Put current global on singly_linked list. */
curr_chain->ch_item = (Dwarf_Global) global;
if (head_chain == NULL)
head_chain = prev_chain = curr_chain;
else {
prev_chain->ch_next = curr_chain;
prev_chain = curr_chain;
}
/* read offset for the *next* entry */
READ_UNALIGNED(dbg, die_offset_in_cu, Dwarf_Off,
pubnames_like_ptr,
pubnames_context->pu_length_size);
pubnames_like_ptr += pubnames_context->pu_length_size;
FIX_UP_OFFSET_IRIX_BUG(dbg,
die_offset_in_cu,
"offset of next die in cu");
if (pubnames_like_ptr > (section_data_ptr + section_length)) {
_dwarf_error(dbg, error, length_err_num);
return (DW_DLV_ERROR);
}
}
/* ASSERT: die_offset_in_cu == 0 */
if (pubnames_like_ptr > pubnames_ptr_past_end_cu) {
/* This is some kind of error. This simply cannot happen.
The encoding is wrong or the length in the header for
this cu's contribution is wrong. */
_dwarf_error(dbg, error, length_err_num);
return (DW_DLV_ERROR);
}
/* If there is some kind of padding at the end of the section,
as emitted by some compilers, skip over that padding and
simply ignore the bytes thus passed-over. With most
compilers, pubnames_like_ptr == pubnames_ptr_past_end_cu at
this point */
pubnames_like_ptr = pubnames_ptr_past_end_cu;
} while (pubnames_like_ptr < (section_data_ptr + section_length));
/* Points to contiguous block of Dwarf_Global's. */
ret_globals = (Dwarf_Global *)
_dwarf_get_alloc(dbg, DW_DLA_LIST, global_count);
if (ret_globals == NULL) {
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return (DW_DLV_ERROR);
}
/*
Store pointers to Dwarf_Global_s structs in contiguous block,
and deallocate the chain. */
curr_chain = head_chain;
for (i = 0; i < global_count; i++) {
*(ret_globals + i) = curr_chain->ch_item;
prev_chain = curr_chain;
curr_chain = curr_chain->ch_next;
dwarf_dealloc(dbg, prev_chain, DW_DLA_CHAIN);
}
*globals = ret_globals;
*return_count = (Dwarf_Signed) global_count;
return DW_DLV_OK;
}
/*
Given a pubnames entry (or other like section entry)
return thru the ret_name pointer
a pointer to the string which is the entry name.
*/
int
dwarf_globname(Dwarf_Global glob, char **ret_name, Dwarf_Error * error)
{
if (glob == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_NULL);
return (DW_DLV_ERROR);
}
*ret_name = (char *) (glob->gl_name);
return DW_DLV_OK;
}
/*
Given a pubnames entry (or other like section entry)
return thru the ret_off pointer the
global offset of the DIE for this entry.
The global offset is the offset within the .debug_info
section as a whole.
*/
int
dwarf_global_die_offset(Dwarf_Global global,
Dwarf_Off * ret_off, Dwarf_Error * error)
{
if (global == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_NULL);
return (DW_DLV_ERROR);
}
if (global->gl_context == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_CONTEXT_NULL);
return (DW_DLV_ERROR);
}
*ret_off = (global->gl_named_die_offset_within_cu +
global->gl_context->pu_offset_of_cu_header);
return DW_DLV_OK;
}
/*
Given a pubnames entry (or other like section entry)
return thru the ret_off pointer the
offset of the compilation unit header of the
compilation unit the global is part of.
In early versions of this, the value returned was
the offset of the compilation unit die, and
other cu-local die offsets were faked so adding this to
such a cu-local offset got a true section offset.
Now things do as they say (adding *cu_header_offset to
a cu-local offset gets the section offset).
*/
int
dwarf_global_cu_offset(Dwarf_Global global,
Dwarf_Off * cu_header_offset,
Dwarf_Error * error)
{
Dwarf_Global_Context con = 0;
if (global == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_NULL);
return (DW_DLV_ERROR);
}
con = global->gl_context;
if (con == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_CONTEXT_NULL);
return (DW_DLV_ERROR);
}
/* In early libdwarf, this incorrectly returned the offset of the
CU DIE. Now correctly returns the header offset. */
*cu_header_offset = con->pu_offset_of_cu_header;
return DW_DLV_OK;
}
/*
Give back the pubnames entry (or any other like section)
name, symbol DIE offset, and the cu-DIE offset.
Various errors are possible.
The string pointer returned thru ret_name is not
dwarf_get_alloc()ed, so no dwarf_dealloc()
DW_DLA_STRING should be applied to it.
*/
int
dwarf_global_name_offsets(Dwarf_Global global,
char **ret_name,
Dwarf_Off * die_offset,
Dwarf_Off * cu_die_offset,
Dwarf_Error * error)
{
Dwarf_Global_Context con = 0;
Dwarf_Debug dbg = 0;
Dwarf_Off off = 0;
if (global == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_NULL);
return (DW_DLV_ERROR);
}
con = global->gl_context;
if (con == NULL) {
_dwarf_error(NULL, error, DW_DLE_GLOBAL_CONTEXT_NULL);
return (DW_DLV_ERROR);
}
off = con->pu_offset_of_cu_header;
/* The offset had better not be too close to the end. If it is,
_dwarf_length_of_cu_header() will step off the end and therefore
must not be used. 10 is a meaningless heuristic, but no CU
header is that small so it is safe. An erroneous offset is due
to a bug in the tool chain. A bug like this has been seen on
IRIX with MIPSpro 7.3.1.3 and an executable > 2GB in size and
with 2 million pubnames entries. */
#define MIN_CU_HDR_SIZE 10
dbg = con->pu_dbg;
if (dbg == NULL) {
_dwarf_error(NULL, error, DW_DLE_DBG_NULL);
return (DW_DLV_ERROR);
}
if (dbg->de_debug_info.dss_size &&
((off + MIN_CU_HDR_SIZE) >= dbg->de_debug_info.dss_size)) {
_dwarf_error(NULL, error, DW_DLE_OFFSET_BAD);
return (DW_DLV_ERROR);
}
#undef MIN_CU_HDR_SIZE
if (die_offset != NULL) {
*die_offset = global->gl_named_die_offset_within_cu + off;
}
*ret_name = (char *) global->gl_name;
if (cu_die_offset != NULL) {
int res = _dwarf_load_debug_info(dbg, error);
if (res != DW_DLV_OK) {
return res;
}
/* The offset had better not be too close to the end. If it is,
_dwarf_length_of_cu_header() will step off the end and
therefore must not be used. 10 is a meaningless heuristic,
but no CU header is that small so it is safe. */
if ((off + 10) >= dbg->de_debug_info.dss_size) {
_dwarf_error(NULL, error, DW_DLE_OFFSET_BAD);
return (DW_DLV_ERROR);
}
*cu_die_offset = off + _dwarf_length_of_cu_header(dbg, off);
}
return DW_DLV_OK;
}
/*
We have the offset to a CU header.
Return thru outFileOffset the offset of the CU DIE.
New June, 2001.
Used by SGI debuggers.
No error is possible.
See also dwarf_CU_dieoffset_given_die().
*/
/* ARGSUSED */
int
dwarf_get_cu_die_offset_given_cu_header_offset(Dwarf_Debug dbg,
Dwarf_Off in_cu_header_offset,
Dwarf_Off * out_cu_die_offset,
Dwarf_Error * err)
{
Dwarf_Off len =
_dwarf_length_of_cu_header(dbg, in_cu_header_offset);
Dwarf_Off newoff = in_cu_header_offset + len;
*out_cu_die_offset = newoff;
return DW_DLV_OK;
}
/* dwarf_CU_dieoffset_given_die returns
the global debug_info section offset of the CU die
that is the CU containing the given (passed-in) die.
This information makes it possible for a consumer to
find and print context information for any die.
Use dwarf_offdie() passing in the offset this returns
to get a die pointer to the CU die.
*/
int
dwarf_CU_dieoffset_given_die(Dwarf_Die die,
Dwarf_Off* return_offset,
Dwarf_Error* error)
{
Dwarf_Off dieoff = 0;
Dwarf_CU_Context cucontext = 0;
CHECK_DIE(die, DW_DLV_ERROR);
cucontext = die->di_cu_context;
dieoff = cucontext->cc_debug_info_offset;
/* The following call cannot fail, so no error check. */
dwarf_get_cu_die_offset_given_cu_header_offset(
cucontext->cc_dbg, dieoff, return_offset,error);
return DW_DLV_OK;
}