/*

  Copyright (C) 2000-2004 Silicon Graphics, Inc.  All Rights Reserved.

  Portions Copyright (C) 2007-2018 David Anderson. All Rights Reserved.

  Portions Copyright 2012 SN Systems Ltd. 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.

*/

#include "config.h"

#include "dwarf_incl.h"

#include <stdio.h>

#include "dwarf_arange.h"

#include "dwarf_global.h"  /* for _dwarf_fixup_* */

/*  Common code for two user-visible routines to share.

    Errors here result in memory leaks, but errors here

    are serious (making aranges unusable) so we assume

    callers will not repeat the error often or mind the leaks.

*/

static int

dwarf_get_aranges_list(Dwarf_Debug dbg,

    Dwarf_Chain  * chain_out,

    Dwarf_Signed * chain_count_out,

    Dwarf_Error  * error)

{

    /* Sweeps through the arange. */

    Dwarf_Small *arange_ptr = 0;

    Dwarf_Small *arange_ptr_start = 0;

    /*  Start of arange header.  Used for rounding offset of arange_ptr

        to twice the tuple size.  Libdwarf requirement. */

    Dwarf_Small *header_ptr = 0;

    /*  Version of .debug_aranges header. */

    Dwarf_Half version = 0;

    /*  Offset of current set of aranges into .debug_info. */

    Dwarf_Off info_offset = 0;

    /*  Size in bytes of addresses in target. */

    Dwarf_Small address_size = 0;

    /*  Size in bytes of segment offsets in target. */

    Dwarf_Small segment_size = 0;

    /*  Count of total number of aranges. */

    Dwarf_Signed arange_count = 0;

    Dwarf_Arange arange = 0;

    Dwarf_Unsigned section_size = 0;

    Dwarf_Byte_Ptr arange_end_section = 0;

    /*  Used to chain Dwarf_Aranges structs. */

    Dwarf_Chain curr_chain = NULL;

    Dwarf_Chain prev_chain = NULL;

    Dwarf_Chain head_chain = NULL;

    if (!dbg->de_debug_aranges.dss_size) {

        return (DW_DLV_NO_ENTRY);

    }

    arange_ptr = dbg->de_debug_aranges.dss_data;

    arange_ptr_start = arange_ptr;

    section_size = dbg->de_debug_aranges.dss_size;

    arange_end_section = arange_ptr + section_size;

    do {

        /*  Length of current set of aranges.

            This is local length, which begins just

            after the length field itself. */

        Dwarf_Unsigned area_length = 0;

        Dwarf_Small remainder = 0;

        Dwarf_Unsigned range_entry_size = 0;

        int local_length_size;

        int local_extension_size = 0;

        Dwarf_Small *end_this_arange = 0;

        header_ptr = arange_ptr;

        if (header_ptr >= arange_end_section) {

            _dwarf_error(dbg, error,DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        /* READ_AREA_LENGTH updates arange_ptr for consumed bytes */

        READ_AREA_LENGTH_CK(dbg, area_length, Dwarf_Unsigned,

            arange_ptr, local_length_size,

            local_extension_size,error,

            section_size,

            arange_end_section);

        /*  arange_ptr has been incremented appropriately past

            the length field by READ_AREA_LENGTH. */

        if (area_length >  dbg->de_debug_aranges.dss_size) {

            _dwarf_error(dbg, error,DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        if ((area_length + local_length_size + local_extension_size) >

            dbg->de_debug_aranges.dss_size) {

            _dwarf_error(dbg, error, DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        end_this_arange = arange_ptr + area_length;

        if (end_this_arange > arange_end_section) {

            _dwarf_error(dbg, error,DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        READ_UNALIGNED_CK(dbg, version, Dwarf_Half,

            arange_ptr, sizeof(Dwarf_Half),

            error,end_this_arange);

        arange_ptr += sizeof(Dwarf_Half);

        if (arange_ptr >= end_this_arange) {

            _dwarf_error(dbg, error, DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        if (version != DW_ARANGES_VERSION2) {

            _dwarf_error(dbg, error, DW_DLE_VERSION_STAMP_ERROR);

            return (DW_DLV_ERROR);

        }

        READ_UNALIGNED_CK(dbg, info_offset, Dwarf_Off,

            arange_ptr, local_length_size,

            error,end_this_arange);

        arange_ptr += local_length_size;

        if (arange_ptr >= end_this_arange) {

            _dwarf_error(dbg, error, DW_DLE_ARANGES_HEADER_ERROR);

            return DW_DLV_ERROR;

        }

        /* This applies to debug_info only, not to debug_types. */

        if (info_offset >= dbg->de_debug_info.dss_size) {

            FIX_UP_OFFSET_IRIX_BUG(dbg, info_offset,

                "arange info offset.a");

            if (info_offset >= dbg->de_debug_info.dss_size) {

                _dwarf_error(dbg, error, DW_DLE_ARANGE_OFFSET_BAD);

                return (DW_DLV_ERROR);

            }

        }

        address_size = *(Dwarf_Small *) arange_ptr;

        if (address_size  > sizeof(Dwarf_Addr)) {

            _dwarf_error(dbg, error, DW_DLE_ADDRESS_SIZE_ERROR);

            return DW_DLV_ERROR;

        }

        if (address_size  ==  0) {

            _dwarf_error(dbg, error, DW_DLE_ADDRESS_SIZE_ZERO);

            return DW_DLV_ERROR;

        }

        /*  It is not an error if the sizes differ.

            Unusual, but not an error. */

        arange_ptr = arange_ptr + sizeof(Dwarf_Small);

        /*  The following deref means we better check the pointer for off-end. */

        if (arange_ptr >= end_this_arange) {

            _dwarf_error(dbg, error, DW_DLE_ARANGE_OFFSET_BAD);

            return DW_DLV_ERROR;

        }

        /*  Even DWARF2 had a segment_size field here, meaning

            size in bytes of a segment descriptor on the target

            system. */

        segment_size = *(Dwarf_Small *) arange_ptr;

        if (segment_size > sizeof(Dwarf_Addr)) {

            _dwarf_error(dbg, error, DW_DLE_SEGMENT_SIZE_BAD);

            return (DW_DLV_ERROR);

        }

        arange_ptr = arange_ptr + sizeof(Dwarf_Small);

        /* Code below will check for == end_this_arange as appropriate. */

        if (arange_ptr > end_this_arange) {

            _dwarf_error(dbg, error, DW_DLE_ARANGE_OFFSET_BAD);

            return (DW_DLV_ERROR);

        }

        range_entry_size = 2*address_size + segment_size;

        /* Round arange_ptr offset to next multiple of address_size. */

        remainder = (Dwarf_Unsigned) (arange_ptr - header_ptr) %

            (range_entry_size);

        if (remainder != 0) {

            arange_ptr = arange_ptr + (2 * address_size) - remainder;

        }

        do {

            Dwarf_Addr range_address = 0;

            Dwarf_Unsigned segment_selector = 0;

            Dwarf_Unsigned range_length = 0;

            /*  For segmented address spaces, the first field to

                read is a segment selector (new in DWARF4).

                Surprising since the segment_size was always there

                in the table header! */

            if ((version  >= 4) && (segment_size != 0)) {

                READ_UNALIGNED_CK(dbg, segment_selector, Dwarf_Unsigned,

                    arange_ptr, segment_size,

                    error,end_this_arange);

                arange_ptr += address_size;

            }

            READ_UNALIGNED_CK(dbg, range_address, Dwarf_Addr,

                arange_ptr, address_size,

                error,end_this_arange);

            arange_ptr += address_size;

            READ_UNALIGNED_CK(dbg, range_length, Dwarf_Unsigned,

                arange_ptr, address_size,

                error,end_this_arange);

            arange_ptr += address_size;

            {

                /*  We used to suppress all-zero entries, but

                    now we return all aranges entries so we show

                    the entire content.  March 31, 2010. */

                arange = (Dwarf_Arange)

                    _dwarf_get_alloc(dbg, DW_DLA_ARANGE, 1);

                if (arange == NULL) {

                    _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);

                    return (DW_DLV_ERROR);

                }

                arange->ar_segment_selector = segment_selector;

                arange->ar_segment_selector_size = segment_size;

                arange->ar_address = range_address;

                arange->ar_length = range_length;

                arange->ar_info_offset = info_offset;

                arange->ar_dbg = dbg;

                arange_count++;

                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);

                }

                curr_chain->ch_item = arange;

                if (head_chain == NULL)

                    head_chain = prev_chain = curr_chain;

                else {

                    prev_chain->ch_next = curr_chain;

                    prev_chain = curr_chain;

                }

            }

            /*  The current set of ranges is terminated by

                range_address 0 and range_length 0, but that

                does not necessarily terminate the ranges for this CU!

                There can be multiple sets in that DWARF

                does not explicitly forbid multiple sets.

                DWARF2,3,4 section 7.20

                We stop short to avoid overrun of the end of the CU.  */

        } while (end_this_arange >= (arange_ptr + range_entry_size));

        /*  A compiler could emit some padding bytes here. dwarf2/3

            (dwarf4 sec 7.20) does not clearly make extra padding

            bytes illegal. */

        if (end_this_arange < arange_ptr) {

            char buf[200];

            Dwarf_Unsigned pad_count = arange_ptr - end_this_arange;

            Dwarf_Unsigned offset = arange_ptr - arange_ptr_start;

            snprintf(buf,sizeof(buf),"DW_DLE_ARANGE_LENGTH_BAD."

                " 0x%" DW_PR_XZEROS DW_PR_DUx

                " pad bytes at offset 0x%" DW_PR_XZEROS DW_PR_DUx

                " in .debug_aranges",

                pad_count, offset);

            dwarf_insert_harmless_error(dbg,buf);

        }

        /*  For most compilers, arange_ptr == end_this_arange at

            this point. But not if there were padding bytes */

        arange_ptr = end_this_arange;

    } while (arange_ptr < arange_end_section);

    if (arange_ptr != arange_end_section) {

        _dwarf_error(dbg, error, DW_DLE_ARANGE_DECODE_ERROR);

        return (DW_DLV_ERROR);

    }

    *chain_out = head_chain;

    *chain_count_out = arange_count;

    return DW_DLV_OK;

}

/*

    This function returns the count of the number of

    aranges in the .debug_aranges section.  It sets

    aranges to point to a block of Dwarf_Arange's

    describing the arange's.  It returns DW_DLV_ERROR

    on error.

    Must be identical in most aspects to

        dwarf_get_aranges_addr_offsets!

*/

int

dwarf_get_aranges(Dwarf_Debug dbg,

    Dwarf_Arange ** aranges,

    Dwarf_Signed * returned_count, Dwarf_Error * error)

{

    /* Count of total number of aranges. */

    Dwarf_Signed arange_count = 0;

    Dwarf_Arange *arange_block = 0;

    /* Used to chain Dwarf_Aranges structs. */

    Dwarf_Chain curr_chain = NULL;

    Dwarf_Chain prev_chain = NULL;

    Dwarf_Chain head_chain = NULL;

    Dwarf_Signed i = 0;

    int res = DW_DLV_ERROR;

    /* ***** BEGIN CODE ***** */

    if (dbg == NULL) {

        _dwarf_error(NULL, error, DW_DLE_DBG_NULL);

        return (DW_DLV_ERROR);

    }

    res = _dwarf_load_section(dbg, &dbg->de_debug_aranges, error);

    if (res != DW_DLV_OK) {

        return res;

    }

    res = dwarf_get_aranges_list(dbg,&head_chain,&arange_count,error);

    if (res != DW_DLV_OK) {

        return res;

    }

    arange_block = (Dwarf_Arange *)

        _dwarf_get_alloc(dbg, DW_DLA_LIST, arange_count);

    if (arange_block == NULL) {

        _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);

        return (DW_DLV_ERROR);

    }

    curr_chain = head_chain;

    for (i = 0; i < arange_count; i++) {

        *(arange_block + i) = curr_chain->ch_item;

        prev_chain = curr_chain;

        curr_chain = curr_chain->ch_next;

        dwarf_dealloc(dbg, prev_chain, DW_DLA_CHAIN);

    }

    *aranges = arange_block;

    *returned_count = (arange_count);

    return DW_DLV_OK;

}

/*

    This function returns DW_DLV_OK if it succeeds

    and DW_DLV_ERR or DW_DLV_OK otherwise.

    count is set to the number of addresses in the

    .debug_aranges section.

    For each address, the corresponding element in

    an array is set to the address itself(aranges) and

    the section offset (offsets).

    Must be identical in most aspects to

        dwarf_get_aranges!

*/

int

_dwarf_get_aranges_addr_offsets(Dwarf_Debug dbg,

    Dwarf_Addr ** addrs,

    Dwarf_Off ** offsets,

    Dwarf_Signed * count,

    Dwarf_Error * error)

{

    Dwarf_Signed i = 0;

    /* Used to chain Dwarf_Aranges structs. */

    Dwarf_Chain curr_chain = NULL;

    Dwarf_Chain prev_chain = NULL;

    Dwarf_Chain head_chain = NULL;

    Dwarf_Signed arange_count = 0;

    Dwarf_Addr *arange_addrs = 0;

    Dwarf_Off *arange_offsets = 0;

    int res = DW_DLV_ERROR;

    /* ***** BEGIN CODE ***** */

    if (error != NULL)

        *error = NULL;

    if (dbg == NULL) {

        _dwarf_error(NULL, error, DW_DLE_DBG_NULL);

        return (DW_DLV_ERROR);

    }

    res = _dwarf_load_section(dbg, &dbg->de_debug_aranges,error);

    if (res != DW_DLV_OK) {

        return res;

    }

    res = dwarf_get_aranges_list(dbg,&head_chain,&arange_count,error);

    if (res != DW_DLV_OK) {

        return res;

    }

    arange_addrs = (Dwarf_Addr *)

        _dwarf_get_alloc(dbg, DW_DLA_ADDR, arange_count);

    if (arange_addrs == NULL) {

        _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);

        return (DW_DLV_ERROR);

    }

    arange_offsets = (Dwarf_Off *)

        _dwarf_get_alloc(dbg, DW_DLA_ADDR, arange_count);

    if (arange_offsets == NULL) {

        _dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);

        return (DW_DLV_ERROR);

    }

    curr_chain = head_chain;

    for (i = 0; i < arange_count; i++) {

        Dwarf_Arange ar = curr_chain->ch_item;

        arange_addrs[i] = ar->ar_address;

        arange_offsets[i] = ar->ar_info_offset;

        prev_chain = curr_chain;

        curr_chain = curr_chain->ch_next;

        dwarf_dealloc(dbg, ar, DW_DLA_ARANGE);

        dwarf_dealloc(dbg, prev_chain, DW_DLA_CHAIN);

    }

    *count = arange_count;

    *offsets = arange_offsets;

    *addrs = arange_addrs;

    return (DW_DLV_OK);

}

/*

    This function takes a pointer to a block

    of Dwarf_Arange's, and a count of the

    length of the block.  It checks if the

    given address is within the range of an

    address range in the block.  If yes, it

    returns the appropriate Dwarf_Arange.

    Otherwise, it returns DW_DLV_ERROR.

*/

int

dwarf_get_arange(Dwarf_Arange * aranges,

    Dwarf_Unsigned arange_count,

    Dwarf_Addr address,

    Dwarf_Arange * returned_arange, Dwarf_Error * error)

{

    Dwarf_Arange curr_arange = 0;

    Dwarf_Unsigned i = 0;

    if (aranges == NULL) {

        _dwarf_error(NULL, error, DW_DLE_ARANGES_NULL);

        return (DW_DLV_ERROR);

    }

    for (i = 0; i < arange_count; i++) {

        curr_arange = *(aranges + i);

        if (address >= curr_arange->ar_address &&

            address <

            curr_arange->ar_address + curr_arange->ar_length) {

            *returned_arange = curr_arange;

            return (DW_DLV_OK);

        }

    }

    return (DW_DLV_NO_ENTRY);

}

/*

    This function takes an Dwarf_Arange,

    and returns the offset of the first

    die in the compilation-unit that the

    arange belongs to.  Returns DW_DLV_ERROR

    on error.

    For an arange, the cu_die can only be from debug_info,

    not debug_types, it seems.

*/

int

dwarf_get_cu_die_offset(Dwarf_Arange arange,

    Dwarf_Off * returned_offset,

    Dwarf_Error * error)

{

    Dwarf_Debug dbg = 0;

    Dwarf_Off offset = 0;

    Dwarf_Unsigned headerlen = 0;

    int cres = 0;

    if (arange == NULL) {

        _dwarf_error(NULL, error, DW_DLE_ARANGE_NULL);

        return (DW_DLV_ERROR);

    }

    dbg = arange->ar_dbg;

    offset = arange->ar_info_offset;

    /* This applies to debug_info only, not to debug_types. */

    if (!dbg->de_debug_info.dss_data) {

        int res = _dwarf_load_debug_info(dbg, error);

        if (res != DW_DLV_OK) {

            return res;

        }

    }

    cres = _dwarf_length_of_cu_header(dbg, offset,

        true, &headerlen,error);

    if (cres != DW_DLV_OK) {

        return cres;

    }

    *returned_offset =  headerlen + offset;

    return DW_DLV_OK;

}

/*  This function takes an Dwarf_Arange,

    and returns the offset of the CU header

    in the compilation-unit that the

    arange belongs to.  Returns DW_DLV_ERROR

    on error.

    Ensures .debug_info loaded so

    the cu_offset is meaningful.  */

int

dwarf_get_arange_cu_header_offset(Dwarf_Arange arange,

    Dwarf_Off * cu_header_offset_returned,

    Dwarf_Error * error)

{

    Dwarf_Debug dbg = 0;

    if (arange == NULL) {

        _dwarf_error(NULL, error, DW_DLE_ARANGE_NULL);

        return (DW_DLV_ERROR);

    }

    dbg = arange->ar_dbg;

    /* This applies to debug_info only, not to debug_types. */

    /*  Like dwarf_get_arange_info this ensures debug_info loaded:

        the cu_header is in debug_info and will be used else

        we would not call dwarf_get_arange_cu_header_offset. */

    if (!dbg->de_debug_info.dss_data) {

        int res = _dwarf_load_debug_info(dbg, error);

        if (res != DW_DLV_OK) {

            return res;

        }

    }

    *cu_header_offset_returned = arange->ar_info_offset;

    return DW_DLV_OK;

}

/*

    This function takes a Dwarf_Arange, and returns

    true if it is not NULL.  It also stores the start

    address of the range in *start, the length of the

    range in *length, and the offset of the first die

    in the compilation-unit in *cu_die_offset.  It

    returns false on error.

    If cu_die_offset returned ensures .debug_info loaded so

    the cu_die_offset is meaningful.

*/

int

dwarf_get_arange_info(Dwarf_Arange arange,

    Dwarf_Addr * start,

    Dwarf_Unsigned * length,

    Dwarf_Off * cu_die_offset, Dwarf_Error * error)

{

    if (arange == NULL) {

        _dwarf_error(NULL, error, DW_DLE_ARANGE_NULL);

        return (DW_DLV_ERROR);

    }

    if (start != NULL)

        *start = arange->ar_address;

    if (length != NULL)

        *length = arange->ar_length;

    if (cu_die_offset != NULL) {

        Dwarf_Debug dbg = arange->ar_dbg;

        Dwarf_Off headerlen = 0;

        Dwarf_Off offset = arange->ar_info_offset;

        int cres = 0;

        /* This applies to debug_info only, not to debug_types. */

        if (!dbg->de_debug_info.dss_data) {

            int res = _dwarf_load_debug_info(dbg, error);

            if (res != DW_DLV_OK) {

                return res;

            }

        }

        cres = _dwarf_length_of_cu_header(dbg, offset,

            true, &headerlen,error);

        if (cres != DW_DLV_OK) {

            return cres;

        }

        *cu_die_offset = headerlen + offset;

    }

    return (DW_DLV_OK);

}

/* New for DWARF4, entries may have segment information.

   *segment is only meaningful if *segment_entry_size is non-zero. */

int

dwarf_get_arange_info_b(Dwarf_Arange arange,

    Dwarf_Unsigned*  segment,

    Dwarf_Unsigned*  segment_entry_size,

    Dwarf_Addr    * start,

    Dwarf_Unsigned* length,

    Dwarf_Off     * cu_die_offset,

    Dwarf_Error   * error)

{

    if (arange == NULL) {

        _dwarf_error(NULL, error, DW_DLE_ARANGE_NULL);

        return (DW_DLV_ERROR);

    }

    if (segment != NULL) {

        *segment = arange->ar_segment_selector;

    }

    if (segment_entry_size != NULL) {

        *segment_entry_size = arange->ar_segment_selector_size;

    }

    if (start != NULL)

        *start = arange->ar_address;

    if (length != NULL)

        *length = arange->ar_length;

    if (cu_die_offset != NULL) {

        Dwarf_Debug dbg = arange->ar_dbg;

        Dwarf_Off offset = arange->ar_info_offset;

        Dwarf_Unsigned headerlen = 0;

        int cres = 0;

        /* This applies to debug_info only, not to debug_types. */

        if (!dbg->de_debug_info.dss_data) {

            int res = _dwarf_load_debug_info(dbg, error);

            if (res != DW_DLV_OK) {

                return res;

            }

        }

        cres = _dwarf_length_of_cu_header(dbg, offset,

            true, &headerlen,error);

        if (cres != DW_DLV_OK) {

            return cres;

        }

        *cu_die_offset = offset + headerlen;

    }

    return (DW_DLV_OK);

}