osprey/libdwarf/libdwarf/dwarf_query.c

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/*
 * Copyright 2005, 2006 PathScale, Inc.  All Rights Reserved.
 */

/*

  Copyright (C) 2000,2002,2004 Silicon Graphics, Inc.  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., 59 Temple Place - Suite 330, Boston MA 02111-1307, 
  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

*/


#include "config.h"
#include "dwarf_incl.h"
#include <stdio.h>
#include "dwarf_die_deliv.h"

int
dwarf_get_address_size(Dwarf_Debug dbg,
           Dwarf_Half * ret_addr_size, Dwarf_Error * error)
{
    Dwarf_Half address_size;

    if (dbg == 0) {
  _dwarf_error(NULL, error, DW_DLE_DBG_NULL);
  return (DW_DLV_ERROR);
    }
    /* length size same as address size */
    address_size = dbg->de_pointer_size;
    *ret_addr_size = address_size;
    return DW_DLV_OK;
}

int
dwarf_dieoffset(Dwarf_Die die,
    Dwarf_Off * ret_offset, Dwarf_Error * error)
{
    CHECK_DIE(die, DW_DLV_ERROR)

  * ret_offset = (die->di_debug_info_ptr -
      die->di_cu_context->cc_dbg->de_debug_info);
    return DW_DLV_OK;
}


/*
    This function returns the offset of
    the die relative to the start of its
    compilation-unit rather than .debug_info.
    Returns DW_DLV_ERROR on error.
*/
int
dwarf_die_CU_offset(Dwarf_Die die,
        Dwarf_Off * cu_off, Dwarf_Error * error)
{
    Dwarf_CU_Context cu_context;

    CHECK_DIE(die, DW_DLV_ERROR)
  cu_context = die->di_cu_context;

    *cu_off =
  (die->di_debug_info_ptr - cu_context->cc_dbg->de_debug_info -
   cu_context->cc_debug_info_offset);
    return DW_DLV_OK;
}


int
dwarf_tag(Dwarf_Die die, Dwarf_Half * tag, Dwarf_Error * error)
{
    CHECK_DIE(die, DW_DLV_ERROR)


  * tag = (die->di_abbrev_list->ab_tag);
    return DW_DLV_OK;
}


int
dwarf_attrlist(Dwarf_Die die,
         Dwarf_Attribute ** attrbuf,
         Dwarf_Signed * attrcnt, Dwarf_Error * error)
{
    Dwarf_Word attr_count = 0;
    Dwarf_Word i;
    Dwarf_Half attr;
    Dwarf_Half attr_form;
    Dwarf_Byte_Ptr abbrev_ptr;
    Dwarf_Abbrev_List abbrev_list;
    Dwarf_Attribute new_attr;
    Dwarf_Attribute head_attr = NULL, curr_attr;
    Dwarf_Attribute *attr_ptr;
    Dwarf_Debug dbg;
    Dwarf_Byte_Ptr info_ptr;

    CHECK_DIE(die, DW_DLV_ERROR)
  dbg = die->di_cu_context->cc_dbg;

    abbrev_list = _dwarf_get_abbrev_for_code(die->di_cu_context,
               die->di_abbrev_list->
               ab_code);
    if (abbrev_list == NULL) {
  _dwarf_error(dbg, error, DW_DLE_DIE_ABBREV_BAD);
  return (DW_DLV_ERROR);
    }
    abbrev_ptr = abbrev_list->ab_abbrev_ptr;

    info_ptr = die->di_debug_info_ptr;
    SKIP_LEB128_WORD(info_ptr)

  do {
  Dwarf_Unsigned utmp2;

  DECODE_LEB128_UWORD(abbrev_ptr, utmp2)
      attr = (Dwarf_Half) utmp2;
  DECODE_LEB128_UWORD(abbrev_ptr, utmp2)
      attr_form = (Dwarf_Half) utmp2;

  if (attr != 0) {
      new_attr =
    (Dwarf_Attribute) _dwarf_get_alloc(dbg, DW_DLA_ATTR, 1);
      if (new_attr == NULL) {
    _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
    return (DW_DLV_ERROR);
      }

      new_attr->ar_attribute = attr;
      new_attr->ar_attribute_form_direct = attr_form;
      new_attr->ar_attribute_form = attr_form;
      if(attr_form == DW_FORM_indirect) {
    Dwarf_Unsigned utmp6;
    /* DECODE_LEB128_UWORD does info_ptr update */
    DECODE_LEB128_UWORD(info_ptr, utmp6)
                attr_form = (Dwarf_Half) utmp6;
          new_attr->ar_attribute_form = attr_form;
      }
      new_attr->ar_cu_context = die->di_cu_context;
      new_attr->ar_debug_info_ptr = info_ptr;

      info_ptr += _dwarf_get_size_of_val(dbg, attr_form, info_ptr,
                 die->di_cu_context->
                 cc_length_size);

      if (head_attr == NULL)
    head_attr = curr_attr = new_attr;
      else {
    curr_attr->ar_next = new_attr;
    curr_attr = new_attr;
      }
      attr_count++;
  }
    } while (attr != 0 || attr_form != 0);

    if (attr_count == 0) {
  *attrbuf = NULL;
  *attrcnt = 0;
  return (DW_DLV_NO_ENTRY);
    }

    attr_ptr = (Dwarf_Attribute *)
  _dwarf_get_alloc(dbg, DW_DLA_LIST, attr_count);
    if (attr_ptr == NULL) {
  _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
  return (DW_DLV_ERROR);
    }

    curr_attr = head_attr;
    for (i = 0; i < attr_count; i++) {
  *(attr_ptr + i) = curr_attr;
  curr_attr = curr_attr->ar_next;
    }

    *attrbuf = attr_ptr;
    *attrcnt = attr_count;
    return (DW_DLV_OK);
}


/*
    This function takes a die, and an attr, and returns
    a pointer to the start of the value of that attr in
    the given die in the .debug_info section.  The form
    is returned in *attr_form.

    Returns NULL on error, or if attr is not found.
    However, *attr_form is 0 on error, and positive 
    otherwise.
*/
static Dwarf_Byte_Ptr
_dwarf_get_value_ptr(Dwarf_Die die,
         Dwarf_Half attr, Dwarf_Half * attr_form)
{
    Dwarf_Byte_Ptr abbrev_ptr;
    Dwarf_Abbrev_List abbrev_list;
    Dwarf_Half curr_attr;
    Dwarf_Half curr_attr_form;
    Dwarf_Byte_Ptr info_ptr;

    abbrev_list = _dwarf_get_abbrev_for_code(die->di_cu_context,
               die->di_abbrev_list->
               ab_code);
    if (abbrev_list == NULL) {
  *attr_form = 0;
  return (NULL);
    }
    abbrev_ptr = abbrev_list->ab_abbrev_ptr;

    info_ptr = die->di_debug_info_ptr;
    SKIP_LEB128_WORD(info_ptr)

    do {
  Dwarf_Unsigned utmp3;

  DECODE_LEB128_UWORD(abbrev_ptr, utmp3)
      curr_attr = (Dwarf_Half) utmp3;
  DECODE_LEB128_UWORD(abbrev_ptr, utmp3)
      curr_attr_form = (Dwarf_Half) utmp3;
  if(curr_attr_form == DW_FORM_indirect) {
                Dwarf_Unsigned utmp6;

          /* DECODE_LEB128_UWORD updates info_ptr */
                DECODE_LEB128_UWORD(info_ptr, utmp6)
                curr_attr_form = (Dwarf_Half) utmp6;
        }

  if (curr_attr == attr) {
      *attr_form = curr_attr_form;
      return (info_ptr);
  }

  info_ptr += _dwarf_get_size_of_val(die->di_cu_context->cc_dbg,
             curr_attr_form, info_ptr,
             die->di_cu_context->
             cc_length_size);
    } while (curr_attr != 0 || curr_attr_form != 0);

    *attr_form = 1;
    return (NULL);
}


int
dwarf_diename(Dwarf_Die die, char **ret_name, Dwarf_Error * error)
{
    Dwarf_Half attr_form;
    Dwarf_Debug dbg;
    Dwarf_Byte_Ptr info_ptr;
    Dwarf_Unsigned string_offset;
    int res;

    CHECK_DIE(die, DW_DLV_ERROR)

  info_ptr = _dwarf_get_value_ptr(die, DW_AT_name, &attr_form);
    if (info_ptr == NULL) {
  if (attr_form == 0) {
      _dwarf_error(die->di_cu_context->cc_dbg, error,
       DW_DLE_DIE_BAD);
      return (DW_DLV_ERROR);
  }
  return DW_DLV_NO_ENTRY;
    }

    if (attr_form == DW_FORM_string) {
  *ret_name = (char *) (info_ptr);
  return DW_DLV_OK;
    }

    dbg = die->di_cu_context->cc_dbg;
    if (attr_form != DW_FORM_strp) {
  _dwarf_error(dbg, error, DW_DLE_ATTR_FORM_BAD);
  return (DW_DLV_ERROR);
    }

    READ_UNALIGNED(dbg, string_offset, Dwarf_Unsigned,
       info_ptr, die->di_cu_context->cc_length_size);

    if (string_offset >= dbg->de_debug_str_size) {
  _dwarf_error(dbg, error, DW_DLE_STRING_OFFSET_BAD);
  return (DW_DLV_ERROR);
    }

    res =
       _dwarf_load_section(dbg,
                           dbg->de_debug_str_index,
                           &dbg->de_debug_str,
                           error);
    if (res != DW_DLV_OK) {
        return res;
    }

    *ret_name = (char *) (dbg->de_debug_str + string_offset);
    return DW_DLV_OK;
}


int
dwarf_hasattr(Dwarf_Die die,
        Dwarf_Half attr,
        Dwarf_Bool * return_bool, Dwarf_Error * error)
{
    Dwarf_Half attr_form;

    CHECK_DIE(die, DW_DLV_ERROR)

  if (_dwarf_get_value_ptr(die, attr, &attr_form) == NULL) {
  if (attr_form == 0) {
      _dwarf_error(die->di_cu_context->cc_dbg, error,
       DW_DLE_DIE_BAD);
      return (DW_DLV_ERROR);
  }
  *return_bool = false;
  return DW_DLV_OK;
    }

    *return_bool = (true);
    return DW_DLV_OK;
}


int
dwarf_attr(Dwarf_Die die,
     Dwarf_Half attr,
     Dwarf_Attribute * ret_attr, Dwarf_Error * error)
{
    Dwarf_Half attr_form;
    Dwarf_Attribute attrib;
    Dwarf_Byte_Ptr info_ptr;
    Dwarf_Debug dbg;

    CHECK_DIE(die, DW_DLV_ERROR)
  dbg = die->di_cu_context->cc_dbg;

    info_ptr = _dwarf_get_value_ptr(die, attr, &attr_form);
    if (info_ptr == NULL) {
  if (attr_form == 0) {
      _dwarf_error(dbg, error, DW_DLE_DIE_BAD);
      return (DW_DLV_ERROR);
  }
  return DW_DLV_NO_ENTRY;
    }

    attrib = (Dwarf_Attribute) _dwarf_get_alloc(dbg, DW_DLA_ATTR, 1);
    if (attrib == NULL) {
  _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
  return (DW_DLV_ERROR);
    }

    attrib->ar_attribute = attr;
    attrib->ar_attribute_form = attr_form;
    attrib->ar_attribute_form_direct = attr_form;
    attrib->ar_cu_context = die->di_cu_context;
    attrib->ar_debug_info_ptr = info_ptr;
    *ret_attr = (attrib);
    return DW_DLV_OK;
}


int
dwarf_lowpc(Dwarf_Die die,
      Dwarf_Addr * return_addr, Dwarf_Error * error)
{
    Dwarf_Addr ret_addr;
    Dwarf_Byte_Ptr info_ptr;
    Dwarf_Half attr_form;
    Dwarf_Debug dbg;

    CHECK_DIE(die, DW_DLV_ERROR)

  dbg = die->di_cu_context->cc_dbg;
    info_ptr = _dwarf_get_value_ptr(die, DW_AT_low_pc, &attr_form);
    if ((info_ptr == NULL && attr_form == 0) ||
  (info_ptr != NULL && attr_form != DW_FORM_addr)) {
  _dwarf_error(dbg, error, DW_DLE_DIE_BAD);
  return (DW_DLV_ERROR);
    }
    if (info_ptr == NULL) {
  return (DW_DLV_NO_ENTRY);
    }


    READ_UNALIGNED(dbg, ret_addr, Dwarf_Addr,
       info_ptr, dbg->de_pointer_size);

    *return_addr = ret_addr;
    return (DW_DLV_OK);
}


int
dwarf_highpc(Dwarf_Die die,
       Dwarf_Addr * return_addr, Dwarf_Error * error)
{
    Dwarf_Addr ret_addr;
    Dwarf_Byte_Ptr info_ptr;
    Dwarf_Half attr_form;
    Dwarf_Debug dbg;

    CHECK_DIE(die, DW_DLV_ERROR)

  dbg = die->di_cu_context->cc_dbg;
    info_ptr = _dwarf_get_value_ptr(die, DW_AT_high_pc, &attr_form);
    if ((info_ptr == NULL && attr_form == 0) ||
  (info_ptr != NULL && attr_form != DW_FORM_addr)) {
  _dwarf_error(dbg, error, DW_DLE_DIE_BAD);
  return (DW_DLV_ERROR);
    }
    if (info_ptr == NULL) {
  return (DW_DLV_NO_ENTRY);
    }

    READ_UNALIGNED(dbg, ret_addr, Dwarf_Addr,
       info_ptr, dbg->de_pointer_size);

    *return_addr = ret_addr;
    return (DW_DLV_OK);
}


/*
    Takes a die, an attribute attr, and checks if attr 
    occurs in die.  Attr is required to be an attribute
    whose form is in the "constant" class.  If attr occurs 
    in die, the value is returned.  
  Returns DW_DLV_OK, DW_DLV_ERROR, or DW_DLV_NO_ENTRY as
    appropriate. Sets the value thru the pointer return_val.
    This function is meant to do all the 
    processing for dwarf_bytesize, dwarf_bitsize, dwarf_bitoffset, 
    and dwarf_srclang.
*/
static int
_dwarf_die_attr_unsigned_constant(Dwarf_Die die,
          Dwarf_Half attr,
          Dwarf_Unsigned * return_val,
          Dwarf_Error * error)
{
    Dwarf_Byte_Ptr info_ptr;
    Dwarf_Half attr_form;
    Dwarf_Unsigned ret_value;
    Dwarf_Debug dbg;

    CHECK_DIE(die, DW_DLV_ERROR)

  dbg = die->di_cu_context->cc_dbg;
    info_ptr = _dwarf_get_value_ptr(die, attr, &attr_form);
    if (info_ptr != NULL) {
  switch (attr_form) {

  case DW_FORM_data1:
      *return_val = (*(Dwarf_Small *) info_ptr);
      return (DW_DLV_OK);

  case DW_FORM_data2:
      READ_UNALIGNED(dbg, ret_value, Dwarf_Unsigned,
         info_ptr, sizeof(Dwarf_Shalf));
      *return_val = ret_value;
      return (DW_DLV_OK);

  case DW_FORM_data4:
      READ_UNALIGNED(dbg, ret_value, Dwarf_Unsigned,
         info_ptr, sizeof(Dwarf_sfixed));
      *return_val = ret_value;
      return (DW_DLV_OK);

  case DW_FORM_data8:
      READ_UNALIGNED(dbg, ret_value, Dwarf_Unsigned,
         info_ptr, sizeof(Dwarf_Unsigned));
      *return_val = ret_value;
      return (DW_DLV_OK);

  case DW_FORM_udata:
      *return_val = (_dwarf_decode_u_leb128(info_ptr, NULL));
      return (DW_DLV_OK);

  default:
      _dwarf_error(dbg, error, DW_DLE_DIE_BAD);
      return (DW_DLV_ERROR);
  }
    }
    if (attr_form == 0) {
  _dwarf_error(dbg, error, DW_DLE_DIE_BAD);
  return (DW_DLV_ERROR);
    }
    return DW_DLV_NO_ENTRY;
}


int
dwarf_bytesize(Dwarf_Die die,
         Dwarf_Unsigned * ret_size, Dwarf_Error * error)
{
    Dwarf_Unsigned luns;
    int res =
  _dwarf_die_attr_unsigned_constant(die, DW_AT_byte_size, &luns,
            error);
    *ret_size = luns;
    return res;
}


int
dwarf_bitsize(Dwarf_Die die,
        Dwarf_Unsigned * ret_size, Dwarf_Error * error)
{
    Dwarf_Unsigned luns;
    int res;

    res =
  _dwarf_die_attr_unsigned_constant(die, DW_AT_bit_size, &luns,
            error);
    *ret_size = luns;
    return res;
}


int
dwarf_bitoffset(Dwarf_Die die,
    Dwarf_Unsigned * ret_size, Dwarf_Error * error)
{
    Dwarf_Unsigned luns;
    int res;

    res =
  _dwarf_die_attr_unsigned_constant(die, DW_AT_bit_offset, &luns,
            error);
    *ret_size = luns;
    return res;
}


/* Refer section 3.1, page 21 in Dwarf Definition. */
int
dwarf_srclang(Dwarf_Die die,
        Dwarf_Unsigned * ret_size, Dwarf_Error * error)
{
    Dwarf_Unsigned luns;
    int res;

    res =
  _dwarf_die_attr_unsigned_constant(die, DW_AT_language, &luns,
            error);
    *ret_size = luns;
    return res;
}


/* Refer section 5.4, page 37 in Dwarf Definition. */
int
dwarf_arrayorder(Dwarf_Die die,
     Dwarf_Unsigned * ret_size, Dwarf_Error * error)
{
    Dwarf_Unsigned luns;
    int res;

    res =
  _dwarf_die_attr_unsigned_constant(die, DW_AT_ordering, &luns,
            error);
    *ret_size = luns;
    return res;
}

/*
  Return DW_DLV_OK if ok
  DW_DLV_ERROR if failure.

  If the die and the attr are not related the result is
  meaningless.
*/
int
dwarf_attr_offset(Dwarf_Die die, Dwarf_Attribute attr, Dwarf_Off * offset,  /* return 
                       offset 
                       thru 
                       this 
                       ptr 
                     */
      Dwarf_Error * error)
{
    Dwarf_Off attroff;

    CHECK_DIE(die, DW_DLV_ERROR)

  attroff = (attr->ar_debug_info_ptr -
       die->di_cu_context->cc_dbg->de_debug_info);
    *offset = attroff;
    return DW_DLV_OK;
}

---