/*
Copyright (c) 2020, David Anderson
All rights reserved.

Redistribution and use in source and binary forms, with
or without modification, are permitted provided that the
following conditions are met:

    Redistributions of source code must retain the above
    copyright notice, this list of conditions and the following
    disclaimer.

    Redistributions in binary form must reproduce the above
    copyright notice, this list of conditions and the following
    disclaimer in the documentation and/or other materials
    provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include <config.h>

#include <stdlib.h> /* free() malloc() */
#include <stdio.h> /* printf debugging */
#include <string.h> /* memset() */

#if defined(_WIN32) && defined(HAVE_STDAFX_H)
#include "stdafx.h"
#endif /* HAVE_STDAFX_H */

#include "dwarf.h"
#include "libdwarf.h"
#include "libdwarf_private.h"
#include "dwarf_base_types.h"
#include "dwarf_opaque.h"
#include "dwarf_alloc.h"
#include "dwarf_error.h"
#include "dwarf_util.h"
#include "dwarf_string.h"
#include "dwarf_loc.h"
#include "dwarf_loclists.h"

#define SIZEOFT8 1
#define SIZEOFT16 2
#define SIZEOFT32 4
#define SIZEOFT64 8

#if 0 /* dump_bytes */
static void
dump_bytes(const char *msg,Dwarf_Small * start, long len)
{
    Dwarf_Small *end = start + len;
    Dwarf_Unsigned max=16;
    Dwarf_Unsigned ct=0;
    Dwarf_Unsigned full=0;
    Dwarf_Small *cur = start;

    printf("%s (0x%lx)\n",msg,(unsigned long)start);
    for (; cur < end; cur++, ++full) {
        if (!ct) {
            printf("[0x%04lx] ",(unsigned long)full);
        }
        printf("%02x", *cur);
        ++ct;
        if ( ct % 4 == 0) {
            printf(" ");
        }
        if ( ct % max == 0) {
            printf("\n");
            ct = 0;
        }
    }
    printf("\n");
}
#endif /*0*/

static void
free_loclists_context(Dwarf_Loclists_Context cx)
{
    if (cx) {
        free(cx->lc_offset_value_array);
        cx->lc_offset_value_array = 0;
        cx->lc_magic = 0;
        free(cx);
    }
}

/*  Used in case of error reading the
    loclists headers (not referring to Dwarf_Loc_Head_c
    here), to clean up. The chain is of
    Dwarf_Loclists_Context items */
static void
free_loclists_chain(Dwarf_Debug dbg, Dwarf_Chain head)
{
    Dwarf_Chain cur = head;
    Dwarf_Chain next = 0;

    if (!head || IS_INVALID_DBG(dbg)) {
        return;
    }
    for ( ;cur; cur = next) {
        next = cur->ch_next;
        if (cur->ch_item) {
            Dwarf_Loclists_Context cx =
                (Dwarf_Loclists_Context)cur->ch_item;
            free_loclists_context(cx);
            cur->ch_item = 0;
            dwarf_dealloc(dbg,cur,DW_DLA_CHAIN);
        }
    }
}

static int
counted_loc_descr(Dwarf_Debug dbg,
    Dwarf_Small *data,
    Dwarf_Small *enddata,
    Dwarf_Unsigned offset,
    Dwarf_Unsigned *loc_ops_overall_size,
    Dwarf_Unsigned *loc_ops_count_len,
    Dwarf_Unsigned *loc_ops_len,
    Dwarf_Small    **opsdata,
    Dwarf_Unsigned *opsoffset,
    Dwarf_Error *  error)
{
    Dwarf_Unsigned ops_len = 0;
    Dwarf_Unsigned leblen = 0;
    DECODE_LEB128_UWORD_LEN_CK(data,ops_len,leblen,
        dbg,error,enddata);
    *loc_ops_count_len = leblen;
    *loc_ops_overall_size = ops_len+leblen;
    *loc_ops_len = ops_len;
    *opsdata = data;
    *opsoffset = offset +leblen;
    return DW_DLV_OK;
}

/*  See also read_single_rle_entry() for similar code */
static int
read_single_lle_entry(Dwarf_Debug dbg,
    Dwarf_Small    *data,
    Dwarf_Unsigned  dataoffset,
    Dwarf_Small    *enddata,
    Dwarf_Half      address_size,
    unsigned       *bytes_count_out,
    unsigned       *entry_kind,
    Dwarf_Unsigned *entry_operand1,
    Dwarf_Unsigned *entry_operand2,
    Dwarf_Unsigned *opsblocksize, /* Just the  expr data */
    Dwarf_Unsigned *opsoffset, /* Just the expr ops data */
    Dwarf_Small   **ops, /*  pointer to expr ops ops */
    Dwarf_Error* error)
{
    Dwarf_Unsigned count = 0;
    Dwarf_Unsigned leblen = 0;
    unsigned int   code = 0;
    Dwarf_Unsigned val1 = 0;
    Dwarf_Unsigned val2 = 0;
    Dwarf_Unsigned loc_ops_overall_size = 0;
    Dwarf_Unsigned loc_ops_count_len = 0;
    Dwarf_Unsigned loc_ops_len = 0;
    Dwarf_Small   *lopsdata = 0;
    Dwarf_Unsigned lopsoffset = 0;
    Dwarf_Small   *startdata = 0;

    /*  Some of these have a  Counted Location Description
        in them. */
    if (data >= enddata) {
        _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
            "DW_DLE_LOCLISTS_ERROR: "
            "An lle entry begins past the end of "
            "its allowed space. Corrupt DWARF.");
        return DW_DLV_ERROR;
    }
    startdata = data;
    code = *data;
    ++data;
    ++count;
    switch(code) {
    case DW_LLE_end_of_list: break;
    case DW_LLE_base_addressx:{
        DECODE_LEB128_UWORD_LEN_CK(data,val1,leblen,
            dbg,error,enddata);
        count += leblen;
        }
        break;
    case DW_LLE_startx_endx:
    case DW_LLE_startx_length:
    case DW_LLE_offset_pair: {
        int res = 0;

        DECODE_LEB128_UWORD_LEN_CK(data,val1,leblen,
            dbg,error,enddata);
        count += leblen;
        DECODE_LEB128_UWORD_LEN_CK(data,val2,leblen,
            dbg,error,enddata);
        count += leblen;
        res = counted_loc_descr(dbg,data,enddata,
            dataoffset,
            &loc_ops_overall_size,
            &loc_ops_count_len,
            &loc_ops_len,
            &lopsdata,
            &lopsoffset,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
        count += loc_ops_overall_size;
        data  += loc_ops_overall_size;

        }
        break;
    case DW_LLE_default_location: {
        int res = 0;

        res = counted_loc_descr(dbg,data,enddata,
            dataoffset,
            &loc_ops_overall_size,
            &loc_ops_count_len,
            &loc_ops_len,
            &lopsdata,
            &lopsoffset,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
        data +=  loc_ops_overall_size;
        count +=  loc_ops_overall_size;
        }
        break;
    case DW_LLE_base_address: {
        READ_UNALIGNED_CK(dbg,val1, Dwarf_Unsigned,
            data,address_size,error,enddata);
        data += address_size;
        count += address_size;
        }
        break;
    case DW_LLE_start_end: {
        int res = 0;

        READ_UNALIGNED_CK(dbg,val1, Dwarf_Unsigned,
            data,address_size,error,enddata);
        data += address_size;
        count += address_size;
        READ_UNALIGNED_CK(dbg,val2, Dwarf_Unsigned,
            data,address_size,error,enddata);
        data += address_size;
        count += address_size;
        res = counted_loc_descr(dbg,data,enddata,
            dataoffset,
            &loc_ops_overall_size,
            &loc_ops_count_len,
            &loc_ops_len,
            &lopsdata,
            &lopsoffset,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
        count += loc_ops_overall_size;
        data +=  loc_ops_overall_size;
        }
        break;
    case DW_LLE_start_length: {
        int res = 0;

        READ_UNALIGNED_CK(dbg,val1, Dwarf_Unsigned,
            data,address_size,error,enddata);
        data += address_size;
        count += address_size;
        DECODE_LEB128_UWORD_LEN_CK(data,val2,leblen,
            dbg,error,enddata);
        count += (unsigned)leblen;
        res = counted_loc_descr(dbg,data,enddata,
            dataoffset,
            &loc_ops_overall_size,
            &loc_ops_count_len,
            &loc_ops_len,
            &lopsdata,
            &lopsoffset,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
        count += loc_ops_overall_size;
        data +=  loc_ops_overall_size;
        }
        break;
    default: {
        if (error) {
            dwarfstring m;

            dwarfstring_constructor(&m);
            dwarfstring_append_printf_u(&m,
                "DW_DLE_LOCLISTS_ERROR: "
                "The loclists entry at .debug_loclists"
                " offset 0x%x" ,dataoffset);
            dwarfstring_append_printf_u(&m,
                " has code 0x%x which is unknown",code);
            _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
                dwarfstring_string(&m));
            dwarfstring_destructor(&m);
        }
        return DW_DLV_ERROR;
        }
        break;
    }
    {
        /*  We want to avoid overflow in additions, and
            the overall section size is a reasonable check
            on count.  The sequence of tests is to
            preserve a testing baseline:
            baselines/hongg2024-02-18-m.base
            otherwise we would test against sectionsize first.*/
        Dwarf_Unsigned sectionsize = dbg->de_debug_loclists.dss_size;

        if (data > enddata || data < startdata ) {
            /*  Corrupt data being read. */
            _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
                "DW_DLE_LOCLISTS_ERROR: "
                "The end of an lle entry is past the end "
                "of its allowed space");
            return DW_DLV_ERROR;
        }
        if (count > sectionsize) {
            /*  Corrupt data being read. */
            _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
                "DW_DLE_LOCLISTS_ERROR: "
                "The number of bytes in a single "
                "loclist entry is "
                "too large to be reasonable");
            return DW_DLV_ERROR;
        }
    }
    *bytes_count_out = (unsigned)count;
    *entry_kind      = (unsigned)code;
    *entry_operand1  = val1;
    *entry_operand2  = val2;
    *opsblocksize    = loc_ops_len;
    *opsoffset = lopsoffset;
    *ops       = lopsdata;
    return DW_DLV_OK;
}

/*  Reads the header. Determines the
    various offsets, including offset
    of the next header. Does no memory
    allocations here. */
int
_dwarf_internal_read_loclists_header(Dwarf_Debug dbg,
    Dwarf_Bool build_offset_array,
    Dwarf_Unsigned contextnum,
    Dwarf_Unsigned sectionlength,
    Dwarf_Small *data,
    Dwarf_Small *end_data,
    Dwarf_Unsigned offset,
    Dwarf_Loclists_Context  buildhere,
    Dwarf_Unsigned *next_offset,
    Dwarf_Error *error)
{
    Dwarf_Small *startdata = data;
    Dwarf_Unsigned arealen = 0;
    int offset_size = 0;
    int exten_size = 0;
    Dwarf_Unsigned version = 0;
    unsigned address_size = 0;
    unsigned segment_selector_size=  0;
    Dwarf_Unsigned offset_entry_count = 0;
    Dwarf_Unsigned localoff = 0;
    Dwarf_Unsigned lists_len = 0;

    READ_AREA_LENGTH_CK(dbg,arealen,Dwarf_Unsigned,
        data,offset_size,exten_size,
        error,
        sectionlength,end_data);
    if (arealen > sectionlength ||
        (arealen+offset_size+exten_size) > sectionlength) {
        dwarfstring m;
        dwarfstring_constructor(&m);
        dwarfstring_append_printf_u(&m,
            "DW_DLE_SECTION_SIZE_ERROR: A .debug_loclists "
            "area size of 0x%x ",arealen);
        dwarfstring_append_printf_u(&m,
            "at offset 0x%x ",offset);
        dwarfstring_append_printf_u(&m,
            "is larger than the entire section size of "
            "0x%x. Corrupt DWARF.",sectionlength);
        _dwarf_error_string(dbg,error,DW_DLE_SECTION_SIZE_ERROR,
            dwarfstring_string(&m));
        dwarfstring_destructor(&m);
        return DW_DLV_ERROR;
    }

    buildhere->lc_length = arealen +offset_size+exten_size;
    buildhere->lc_dbg = dbg;
    buildhere->lc_index = contextnum;
    buildhere->lc_header_offset = offset;
    buildhere->lc_offset_size = offset_size;
    buildhere->lc_extension_size = exten_size;
    READ_UNALIGNED_CK(dbg,version,Dwarf_Unsigned,data,
        SIZEOFT16,error,end_data);
    if (version != DW_CU_VERSION5) {
        dwarfstring m;
        dwarfstring_constructor(&m);
        dwarfstring_append_printf_u(&m,
            "DW_DLE_VERSION_STAMP_ERROR: The version should be 5 "
            "but we find %u instead.",version);
        _dwarf_error_string(dbg,error,DW_DLE_VERSION_STAMP_ERROR,
            dwarfstring_string(&m));
        dwarfstring_destructor(&m);
        return DW_DLV_ERROR;
    }
    buildhere->lc_version = (Dwarf_Half)version;
    data += SIZEOFT16;

    READ_UNALIGNED_CK(dbg,address_size,unsigned,data,
        SIZEOFT8,error,end_data);
    if (address_size != 4 && address_size != 8 &&
        address_size != 2) {
        dwarfstring m;
        dwarfstring_constructor(&m);
        dwarfstring_append_printf_u(&m,
            " DW_DLE_ADDRESS_SIZE_ERROR: The address size "
            "of %u is not supported.",address_size);
        _dwarf_error_string(dbg,error,DW_DLE_ADDRESS_SIZE_ERROR,
            dwarfstring_string(&m));
        dwarfstring_destructor(&m);
        return DW_DLV_ERROR;
    }
    buildhere->lc_address_size = address_size;
    data++;

    READ_UNALIGNED_CK(dbg,segment_selector_size,unsigned,data,
        SIZEOFT8,error,end_data);
    buildhere->lc_segment_selector_size = segment_selector_size;
    if (buildhere->lc_segment_selector_size) {
        _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
            "DW_DLE_LOCLISTS_ERROR: "
            " The debug_loclists segment selector size is non-zero. "
            "Not supported.");
        return DW_DLV_ERROR;
    }
    data++;

    READ_UNALIGNED_CK(dbg,offset_entry_count,Dwarf_Unsigned,data,
        SIZEOFT32,error,end_data);
    buildhere->lc_offset_entry_count = offset_entry_count;
    data += SIZEOFT32;
    if (offset_entry_count >= (sectionlength/offset_size)) {
        _dwarf_error_string(dbg,error,DW_DLE_LOCLISTS_ERROR,
            "dbg,DW_DLE_LOCLISTS_ERROR: "
            " The debug_loclists offset table entry "
            "count exceeds the "
            "section length, Corrupt dwarf");
        return DW_DLV_ERROR;
    }
    localoff = data - startdata;
    if (offset_entry_count) {
        buildhere->lc_offsets_array = data;
        lists_len += offset_size*offset_entry_count;
        if (build_offset_array) {
            Dwarf_Unsigned tabentrynum = 0;

            buildhere->lc_offset_value_array = (Dwarf_Unsigned *)
                calloc(offset_entry_count, sizeof(Dwarf_Unsigned));
            if (!buildhere->lc_offset_value_array) {
                _dwarf_error_string(dbg,error, DW_DLE_ALLOC_FAIL,
                    "dbg,DW_DLE_ALLOC_CAIL: "
                    " The debug_loclists offset table "
                    "cannot be allocated.");
                return DW_DLV_ERROR;
            }
            for (tabentrynum = 0 ; tabentrynum < offset_entry_count;
                data += offset_size,++tabentrynum ) {
                Dwarf_Unsigned entry = 0;
                int res = 0;

                res = _dwarf_read_unaligned_ck_wrapper(dbg,
                    &entry,data,offset_size,end_data,error);
                if (res != DW_DLV_OK) {
                    free(buildhere->lc_offset_value_array);
                    buildhere->lc_offset_value_array = 0;
                    return res;
                }
                buildhere->lc_offset_value_array[tabentrynum] =
                    entry;
            }
        }
    } /* else no offset table */

    buildhere->lc_offsets_off_in_sect = offset+localoff;
    buildhere->lc_first_loclist_offset = offset+localoff+
        lists_len;
    buildhere->lc_loclists_header = startdata;
    buildhere->lc_endaddr = startdata +buildhere->lc_length;
    buildhere->lc_past_last_loclist_offset =
        buildhere->lc_header_offset +buildhere->lc_length;
    *next_offset =  buildhere->lc_past_last_loclist_offset;
    return DW_DLV_OK;
}

/*  We return a pointer to an array of contexts
    (not context pointers through *cxt if
    we succeed and are returning DW_DLV_OK.
    We never return DW_DLV_NO_ENTRY here. */
static int
internal_load_loclists_contexts(Dwarf_Debug dbg,
    Dwarf_Loclists_Context **cxt,
    Dwarf_Unsigned *count,
    Dwarf_Error *error)
{
    Dwarf_Unsigned offset = 0;
    Dwarf_Unsigned nextoffset = 0;
    Dwarf_Small  * data = dbg->de_debug_loclists.dss_data;
    Dwarf_Unsigned section_size = dbg->de_debug_loclists.dss_size;
    Dwarf_Small  * startdata = data;
    Dwarf_Small  * end_data = data +section_size;
    Dwarf_Chain curr_chain = 0;
    Dwarf_Chain head_chain = 0;
    Dwarf_Chain *plast = &head_chain;
    int res = 0;
    Dwarf_Unsigned chainlength = 0;
    Dwarf_Loclists_Context *fullarray = 0;
    Dwarf_Unsigned i = 0;

    for ( ; data < end_data ; data = startdata+nextoffset) {
        Dwarf_Loclists_Context newcontext = 0;

        /* sizeof the context struct, not sizeof a pointer */
        newcontext = malloc(sizeof(*newcontext));
        if (!newcontext) {
            free_loclists_chain(dbg,head_chain);
            _dwarf_error_string(dbg,error,
                DW_DLE_ALLOC_FAIL,
                "DW_DLE_ALLOC_FAIL: Allocation of "
                "Loclists_Context failed");
            return DW_DLV_ERROR;
        }
        memset(newcontext,0,sizeof(*newcontext));
        res = _dwarf_internal_read_loclists_header(dbg, TRUE,
            chainlength,
            section_size,
            data,end_data,offset,
            newcontext,&nextoffset,error);
        if (res == DW_DLV_ERROR) {
            free_loclists_chain(dbg,head_chain);
            free_loclists_context(newcontext);
            newcontext = 0;
            return DW_DLV_ERROR;
        }
        newcontext->lc_magic = LOCLISTS_MAGIC;
        curr_chain = (Dwarf_Chain)
            _dwarf_get_alloc(dbg, DW_DLA_CHAIN, 1);
        if (curr_chain == NULL) {
            _dwarf_error_string(dbg, error, DW_DLE_ALLOC_FAIL,
                "DW_DLE_ALLOC_FAIL: allocating Loclists_Context"
                " chain entry");
            free_loclists_chain(dbg,head_chain);
            free_loclists_context(newcontext);
            newcontext = 0;
            return DW_DLV_ERROR;
        }
        curr_chain->ch_item = newcontext;
        ++chainlength;
        (*plast) = curr_chain;
        plast = &(curr_chain->ch_next);
        offset = nextoffset;
    }
    fullarray= (Dwarf_Loclists_Context *)malloc(
        chainlength *sizeof(Dwarf_Loclists_Context /*pointer*/));
    if (!fullarray) {
        free_loclists_chain(dbg,head_chain);
        _dwarf_error_string(dbg,error,
            DW_DLE_ALLOC_FAIL,"Allocation of "
            "Loclists_Context pointer array failed");
        return DW_DLV_ERROR;
    }
    curr_chain = head_chain;
    for (i = 0; i < chainlength; ++i) {
        Dwarf_Chain prev = 0;
        fullarray[i] = (Dwarf_Loclists_Context)curr_chain->ch_item;
        curr_chain->ch_item = 0;
        prev = curr_chain;
        curr_chain = curr_chain->ch_next;
        dwarf_dealloc(dbg, prev, DW_DLA_CHAIN);
    }
    /*  ASSERT: the chain is entirely alloc'd
        and the array of pointers points to
        individually malloc'd Dwarf_Loclists_Context_s */
    *cxt = fullarray;
    *count = chainlength;
    return DW_DLV_OK;
}

/*  Used by dwarfdump to print raw loclists data.
    Loads all the .debug_loclists[.dwo]  headers and
    returns DW_DLV_NO_ENTRY if the section
    is missing or empty.
    Intended to be done quite early and
    done exactly once.
    Harmless to do more than once.
    With DW_DLV_OK it returns the number of
    loclists headers in the section through
    loclists_count. */
int
dwarf_load_loclists(Dwarf_Debug dbg,
    Dwarf_Unsigned *loclists_count,
    Dwarf_Error *error)
{
    int res = DW_DLV_ERROR;
    Dwarf_Loclists_Context *cxt = 0;
    Dwarf_Unsigned count = 0;

    CHECK_DBG(dbg,error,"dwarf_load_loclists()");
    if (dbg->de_loclists_context) {
        if (loclists_count) {
            *loclists_count = dbg->de_loclists_context_count;
        }
        return DW_DLV_OK;
    }
    if (!dbg->de_debug_loclists.dss_size) {
        /* nothing there. */
        return DW_DLV_NO_ENTRY;
    }
    if (!dbg->de_debug_loclists.dss_data) {
        res = _dwarf_load_section(dbg, &dbg->de_debug_loclists,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
    }
    /*  cxt is set to a pointer to a context, which is
        actually an array of pointers to such contexts, 'count'
        of them. Each context has the loclists offset table
        (if it has at least on entry in the table)
        pointed in each cxt. */
    res = internal_load_loclists_contexts(dbg,&cxt,&count,error);
    if (res == DW_DLV_ERROR) {
        return res;
    }
    dbg->de_loclists_context = cxt;
    dbg->de_loclists_context_count = count;
    if (loclists_count) {
        *loclists_count = count;
    }
    return DW_DLV_OK;
}

/*  Frees the memory in use in all loclists contexts.
    Done by dwarf_finish()  */
void
_dwarf_dealloc_loclists_context(Dwarf_Debug dbg)
{
    Dwarf_Unsigned i = 0;
    Dwarf_Loclists_Context * loccon = 0;

    if (!dbg->de_loclists_context) {
        return;
    }
    loccon = dbg->de_loclists_context;
    for ( ; i < dbg->de_loclists_context_count; ++i) {
        Dwarf_Loclists_Context con = loccon[i];
        free_loclists_context(con);
        loccon[i] = 0;
    }
    free(dbg->de_loclists_context);
    dbg->de_loclists_context = 0;
    dbg->de_loclists_context_count = 0;
}

/*  Used by dwarfdump to print raw loclists data. */
int
dwarf_get_loclist_offset_index_value(Dwarf_Debug dbg,
    Dwarf_Unsigned context_index,
    Dwarf_Unsigned offsetentry_index,
    Dwarf_Unsigned * offset_value_out,
    Dwarf_Unsigned * global_offset_value_out,
    Dwarf_Error *error)
{
    Dwarf_Loclists_Context con = 0;
    unsigned offset_len = 0;
    Dwarf_Small *offsetptr = 0;
    Dwarf_Unsigned targetoffset = 0;

    CHECK_DBG(dbg,error,"dwarf_get_loclist_offset_index_value()");
    if (!dbg->de_loclists_context_count) {
    }
    if (context_index >= dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    con = dbg->de_loclists_context[context_index];
    if (!con || con->lc_magic != LOCLISTS_MAGIC) {
        _dwarf_error_string(dbg, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "context NULL or not LOCLISTS_MAGIC "
            "found in "
            "dwarf_get_loclist_offset_index_value()");
        return DW_DLV_ERROR;
    }

    if (offsetentry_index >= con->lc_offset_entry_count) {
        return DW_DLV_NO_ENTRY;
    }
    offset_len = con->lc_offset_size;
    offsetptr = con->lc_offsets_array +
        (offsetentry_index*offset_len);
    READ_UNALIGNED_CK(dbg,targetoffset,Dwarf_Unsigned,
        offsetptr,
        offset_len,error,con->lc_endaddr);
    if (offset_value_out) {
        *offset_value_out = targetoffset;
    }
    if (global_offset_value_out) {
        *global_offset_value_out = targetoffset +
            con->lc_offsets_off_in_sect;
    }
    return DW_DLV_OK;
}

/*  Used by dwarfdump to print basic data from the
    data generated to look at a specific loclist
    as returned by  dwarf_loclists_index_get_rle_head()
    or dwarf_loclists_offset_get_rle_head. */
int dwarf_get_loclist_head_basics(Dwarf_Loc_Head_c head,
    Dwarf_Small    * lkind,
    Dwarf_Unsigned * lle_count,
    Dwarf_Unsigned * lle_version,
    Dwarf_Unsigned * loclists_index_returned,
    Dwarf_Unsigned * bytes_total_in_lle,
    Dwarf_Half     * offset_size,
    Dwarf_Half     * address_size,
    Dwarf_Half     * segment_selector_size,
    Dwarf_Unsigned * overall_offset_of_this_context,
    Dwarf_Unsigned * total_length_of_this_context,
    Dwarf_Unsigned * offset_table_offset,
    Dwarf_Unsigned * offset_table_entrycount,
    Dwarf_Bool     * loclists_base_present,
    Dwarf_Unsigned * loclists_base,
    Dwarf_Bool     * loclists_base_address_present,
    Dwarf_Unsigned * loclists_base_address,
    Dwarf_Bool     * loclists_debug_addr_base_present,
    Dwarf_Unsigned * loclists_debug_addr_base,
    Dwarf_Unsigned * loclists_offset_lle_set,
    Dwarf_Error *error)
{
    Dwarf_Loclists_Context loccontext = 0;

    if (!head) {
        _dwarf_error_string(NULL, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "NULL Dwarf_Loc_Head_c "
            "argument passed to "
            "dwarf_get_loclist_head_basics()");
        return DW_DLV_ERROR;
    }
    if (head->ll_magic != LOCLISTS_MAGIC) {
        _dwarf_error_string(NULL, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "NULL Dwarf_Loc_Head_c "
            " not set with LOCLISTS_MAGIC in "
            "argument passed to "
            "dwarf_get_loclist_head_basics()");
        return DW_DLV_ERROR;
    }
    *lkind = (Dwarf_Small)head->ll_lkind;
    *lle_count = head->ll_locdesc_count;
    *lle_version = head->ll_cuversion;
    *loclists_index_returned = head->ll_index;
    *bytes_total_in_lle = head->ll_bytes_total;
    *offset_size = head->ll_offset_size;
    *address_size = head->ll_address_size;
    *segment_selector_size = head->ll_segment_selector_size;
    /*  If a dwarf_expression, no ll_loccontext */
    loccontext = head->ll_localcontext;
    if (loccontext) {
        *overall_offset_of_this_context =
            loccontext->lc_header_offset;
        *total_length_of_this_context = loccontext->lc_length;
        *offset_table_offset =  loccontext->lc_offsets_off_in_sect;
        *offset_table_entrycount = loccontext->lc_offset_entry_count;
    }
    *loclists_base_present = head->ll_at_loclists_base_present;
    *loclists_base= head->ll_at_loclists_base;

    *loclists_base_address_present = head->ll_cu_base_address_present;
    *loclists_base_address= head->ll_cu_base_address;

    *loclists_debug_addr_base_present = head->ll_cu_addr_base_present;
    *loclists_debug_addr_base  = head->ll_cu_addr_base;
    *loclists_offset_lle_set = head->ll_llearea_offset;
    return DW_DLV_OK;
}

/*  Used by dwarfdump to print raw loclists data.
    Enables printing of details about the Range List Table
    Headers, one header per call. Index starting at 0.
    Returns DW_DLV_NO_ENTRY if index is too high for the table.
    A .debug_loclists section may contain any number
    of Range List Table Headers with their details.  */
int
dwarf_get_loclist_context_basics(Dwarf_Debug dbg,
    Dwarf_Unsigned context_index,
    Dwarf_Unsigned * header_offset,
    Dwarf_Small    * offset_size,
    Dwarf_Small    * extension_size,
    unsigned       * version, /* 5 */
    Dwarf_Small    * address_size,
    Dwarf_Small    * segment_selector_size,
    Dwarf_Unsigned * offset_entry_count,
    Dwarf_Unsigned * offset_of_offset_array,
    Dwarf_Unsigned * offset_of_first_loclistentry,
    Dwarf_Unsigned * offset_past_last_loclistentry,
    Dwarf_Error *error)
{
    Dwarf_Loclists_Context con = 0;

    CHECK_DBG(dbg,error,"dwarf_get_loclist_context_basics()");
    if (!dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    if (context_index >= dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    con = dbg->de_loclists_context[context_index];
    if (!con || con->lc_magic != LOCLISTS_MAGIC) {
        _dwarf_error_string(dbg, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "context NULL or not LOCLISTS_MAGIC "
            "found in "
            "dwarf_get_loclist_context_basics()");
        return DW_DLV_ERROR;
    }
    if (header_offset) {
        *header_offset = con->lc_header_offset;
    }
    if (offset_size) {
        *offset_size = con->lc_offset_size;
    }
    if (extension_size) {
        *extension_size = con->lc_extension_size;
    }
    if (version) {
        *version = con->lc_version;
    }
    if (address_size) {
        *address_size = con->lc_address_size;
    }
    if (segment_selector_size) {
        *segment_selector_size = con->lc_segment_selector_size;
    }
    if (offset_entry_count) {
        *offset_entry_count = con->lc_offset_entry_count;
    }
    if (offset_of_offset_array) {
        *offset_of_offset_array = con->lc_offsets_off_in_sect;
    }
    if (offset_of_first_loclistentry) {
        *offset_of_first_loclistentry = con->lc_first_loclist_offset;
    }
    if (offset_past_last_loclistentry) {
        *offset_past_last_loclistentry =
            con->lc_past_last_loclist_offset;
    }
    return DW_DLV_OK;
}

/*  Used by dwarfdump to print raw loclists data.
    entry offset is offset_of_first_loclistentry.
    Stop when the returned *next_entry_offset
    is == offset_past_last_loclistentry (from
    dwarf_get_loclist_context_plus).
    This only makes sense within those loclists
    This retrieves raw detail from the section,
    no base values or anything are added.
    So this returns raw individual entries
    for a single loclist header, meaning a
    a single Dwarf_Loclists_Context.  */
int dwarf_get_loclist_lle(Dwarf_Debug dbg,
    Dwarf_Unsigned contextnumber,
    Dwarf_Unsigned entry_offset,
    Dwarf_Unsigned endoffset,
    unsigned *entrylen,
    unsigned *entry_kind,
    Dwarf_Unsigned *entry_operand1,
    Dwarf_Unsigned *entry_operand2,
    Dwarf_Unsigned *expr_ops_blocksize,
    Dwarf_Unsigned *expr_ops_offset,
    Dwarf_Small   **expr_opsdata,
    Dwarf_Error *error)
{
    Dwarf_Loclists_Context con = 0;
    Dwarf_Small *data = 0;
    Dwarf_Small *enddata = 0;
    int res = 0;
    Dwarf_Half address_size = 0;

    CHECK_DBG(dbg,error,"dwarf_get_loclist_lle()");
    if (!dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    data = dbg->de_debug_loclists.dss_data +
        entry_offset;
    enddata = dbg->de_debug_loclists.dss_data +
        endoffset;
    if (contextnumber >= dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    con = dbg->de_loclists_context[contextnumber];
    if (!con || con->lc_magic != LOCLISTS_MAGIC) {
        _dwarf_error_string(dbg, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "context NULL or not LOCLISTS_MAGIC "
            "found in "
            "dwarf_get_loclist_lle()");
        return DW_DLV_ERROR;
    }
    address_size = con->lc_address_size;
    res = read_single_lle_entry(dbg,
        data,entry_offset,enddata,
        address_size, entrylen,
        entry_kind, entry_operand1, entry_operand2,
        expr_ops_blocksize,
        expr_ops_offset,
        expr_opsdata,
        error);
    return res;
}

static int
_dwarf_which_loclists_context(Dwarf_Debug dbg,
    Dwarf_CU_Context ctx,
    Dwarf_Unsigned loclist_offset,
    Dwarf_Unsigned *index,
    Dwarf_Error *error)
{
    Dwarf_Unsigned          count = 0;
    Dwarf_Loclists_Context *array = 0;
    Dwarf_Unsigned          i = 0;
    Dwarf_Loclists_Context  rcx = 0;
    Dwarf_Unsigned          rcxoff = 0;
    Dwarf_Unsigned          rcxend = 0;

    array = dbg->de_loclists_context;
    count = dbg->de_loclists_context_count;
    if (!array) {
        return DW_DLV_NO_ENTRY;
    }
    rcx = array[i];
    rcxoff = rcx->lc_header_offset;
    rcxend = rcxoff + rcx->lc_length;
    if (!ctx->cc_loclists_base_present) {
        /* We look at the location of each loclist context
            to find one with the offset the DIE gave us. */
        for ( i = 0 ; i < count; ++i) {
            rcx = array[i];
            rcxoff = rcx->lc_header_offset;
            rcxend = rcxoff +
                rcx->lc_length;
            rcxend = rcxoff +
                rcx->lc_length;
            if (loclist_offset < rcxoff){
                continue;
            }
            if (loclist_offset < rcxend ){
                *index = i;
                return DW_DLV_OK;
            }
        }
        {
            dwarfstring m;

            dwarfstring_constructor(&m);
            dwarfstring_append_printf_u(&m,
                "DW_DLE_LOCLISTS_ERROR: loclist ran off end "
                " finding target offset of"
                " 0x%" DW_PR_XZEROS DW_PR_DUx ,loclist_offset);
            dwarfstring_append(&m,
                " Not found anywhere in .debug_loclists "
                "data. Corrupted data?");
            _dwarf_error_string(dbg,error,
                DW_DLE_LOCLISTS_ERROR,
                dwarfstring_string(&m));
            dwarfstring_destructor(&m);
            return DW_DLV_ERROR;
        }
    } else {
        /*  We have a DW_AT_loclists_base (lc_loclists_base),
            let's use it. */
        Dwarf_Unsigned lookfor = 0;;
        lookfor = ctx->cc_loclists_base;
        for ( i = 0 ; i < count; ++i) {
            dwarfstring m;

            rcx = array[i];
            if (rcx->lc_offsets_off_in_sect == lookfor){
                *index = i;
                return DW_DLV_OK;
            }
            if (rcx->lc_offsets_off_in_sect < lookfor){
                continue;
            }

            dwarfstring_constructor(&m);
            dwarfstring_append_printf_u(&m,
                "DW_DLE_LOCLISTS_ERROR: loclists base of "
                " 0x%" DW_PR_XZEROS DW_PR_DUx ,lookfor);
            dwarfstring_append_printf_u(&m,
                " was not found though we are now at base "
                " 0x%" DW_PR_XZEROS DW_PR_DUx ,
                rcx->lc_offsets_off_in_sect);
            _dwarf_error_string(dbg,error,
                DW_DLE_LOCLISTS_ERROR,
                dwarfstring_string(&m));
            dwarfstring_destructor(&m);
            return DW_DLV_ERROR;
        }
        {
            dwarfstring m;

            dwarfstring_constructor(&m);
            dwarfstring_append_printf_u(&m,
                "DW_DLE_LOCLISTS_ERROR: loclist base of "
                " 0x%" DW_PR_XZEROS DW_PR_DUx ,lookfor);
            dwarfstring_append(&m,
                " was not found anywhere in .debug_loclists "
                "data. Corrupted data?");
            _dwarf_error_string(dbg,error,
                DW_DLE_LOCLISTS_ERROR,
                dwarfstring_string(&m));
            dwarfstring_destructor(&m);
            return DW_DLV_ERROR;
        }
    }
    return DW_DLV_ERROR;
}

/*  Caller will eventually free as appropriate. */
static int
alloc_rle_and_append_to_list(Dwarf_Debug dbg,
    Dwarf_Loc_Head_c rctx,
    Dwarf_Locdesc_c *e_out,
    Dwarf_Error *error)
{
    Dwarf_Locdesc_c e = 0;

    e = malloc(sizeof(struct Dwarf_Locdesc_c_s));
    if (!e) {
        _dwarf_error_string(dbg, error, DW_DLE_ALLOC_FAIL,
            "DW_DLE_ALLOC_FAIL: Out of memory in "
            "building list of loclists entries on a DIE.");
        return DW_DLV_ERROR;
    }
    memset(e,0,sizeof(struct Dwarf_Locdesc_c_s));
    _dwarf_locdesc_c_constructor(dbg,e);
    e->ld_magic = LOCLISTS_MAGIC;
    if (rctx->ll_first) {
        rctx->ll_last->ld_next = e;
        rctx->ll_last = e;
    } else {
        rctx->ll_first = e;
        rctx->ll_last = e;
    }
    rctx->ll_locdesc_count++;
    *e_out = e;
    return DW_DLV_OK;
}

static int
_dwarf_implicit_loclists_base(Dwarf_Debug dbg,
    Dwarf_Unsigned indexval,
    Dwarf_Unsigned *ibase)
{
    Dwarf_Loclists_Context rctx = 0;
    if (IS_INVALID_DBG(dbg)) {
        return DW_DLV_NO_ENTRY;
    }
    if (!dbg->de_debug_loclists.dss_size) {
        return DW_DLV_NO_ENTRY;
    }
    if (!dbg->de_loclists_context_count) {
        return DW_DLV_NO_ENTRY;
    }
    /*  This implicit base can only work if the 0-th
        Rnglists_Context is appropriate here. */
    rctx = dbg->de_loclists_context[0];
    if (indexval > rctx->lc_offset_entry_count) {
        /*  We are not using base offset, we
            will not see a DW_FORM_loclistx */
        return DW_DLV_NO_ENTRY;
    }
    *ibase = rctx->lc_offsets_off_in_sect;
    return DW_DLV_OK;
}

/*  Read the group of loclists entries, and
    finally build an array of Dwarf_Locdesc_c
    records. Attach to rctx here.
    Since on error the caller will destruct the rctx
    and we ensure to attach allocations there
    the caller will destruct the allocations here
    in case we return DW_DLV_ERROR*/
static int
build_array_of_lle(Dwarf_Debug dbg,
    Dwarf_Loc_Head_c rctx,
    Dwarf_Error *error)
{
    int res = 0;
    Dwarf_Small   *data         = rctx->ll_llepointer;
    Dwarf_Unsigned dataoffset   = rctx->ll_llearea_offset;
    Dwarf_Small   *enddata      = rctx->ll_end_data_area;
    unsigned int   offset_size  = rctx->ll_offset_size;
    unsigned int   address_size = rctx->ll_address_size;
    Dwarf_Unsigned bytescounttotal= 0;
    int            done           = FALSE;
    Dwarf_Unsigned i              = 0;

    for ( ; !done  ; ) {
        unsigned int    entrylen = 0;
        unsigned int    code = 0;
        Dwarf_Unsigned  val1 = 0;
        Dwarf_Unsigned  val2 = 0;
        Dwarf_Locdesc_c e = 0;
        Dwarf_Unsigned  opsblocksize  = 0;
        Dwarf_Unsigned  opsoffset  = 0;
        Dwarf_Small    *ops = 0;
        Dwarf_Block_c   eops;

        memset(&eops,0,sizeof(eops));
        res = read_single_lle_entry(dbg,
            data,dataoffset, enddata,
            address_size,&entrylen,
            &code,&val1, &val2,
            &opsblocksize,&opsoffset,&ops,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
        res = alloc_rle_and_append_to_list(dbg,rctx,&e,error);
        if (res != DW_DLV_OK) {
            return res;
        }
        eops.bl_len =opsblocksize;
        eops.bl_data = ops;
        eops.bl_kind = rctx->ll_lkind;
        eops.bl_section_offset = opsoffset;
        eops.bl_locdesc_offset = dataoffset;
        e->ld_lkind = rctx->ll_lkind;
        e->ld_magic = LOCLISTS_MAGIC;
        e->ld_lle_value = code,
        e->ld_entrylen = entrylen;
        e->ld_rawlow = val1;
        e->ld_rawhigh = val2;
        e->ld_opsblock = eops;
        e->ld_lle_bytecount = entrylen;
        data += entrylen;
        bytescounttotal += entrylen;
        if (code == DW_LLE_end_of_list) {
            /*  This terminates the entries for a loclist portion.*/
            done = TRUE;
            break;
        }
    }
    if (rctx->ll_locdesc_count > 0) {
        Dwarf_Locdesc_c array = 0;
        Dwarf_Locdesc_c cur = 0;
        Dwarf_Locdesc_c prev = 0;

        /* array of structs. Here we copy the previous
            malloc set of Dwarf_Locdesc_c into
            a dwarf_get_alloc set and free the malloc set */

        array = (Dwarf_Locdesc_c)_dwarf_get_alloc(dbg,
            DW_DLA_LOCDESC_C, rctx->ll_locdesc_count);
        if (!array) {
            _dwarf_error_string(dbg, error, DW_DLE_ALLOC_FAIL,
                "DW_DLE_ALLOC_FAIL: Out of memory in "
                "copying list of locdescs into array ");
            return DW_DLV_ERROR;
        }
        rctx->ll_locdesc = array;
        cur = rctx->ll_first;
        for (i = 0  ; i < rctx->ll_locdesc_count; ++i) {
            prev = cur;
            array[i] = *cur;
            cur = cur->ld_next;
            free(prev);
        }
        rctx->ll_first = 0;
        rctx->ll_last = 0;
    }
    for (i = 0; i < rctx->ll_locdesc_count; ++i) {
        Dwarf_Locdesc_c ldc = rctx->ll_locdesc + i;

        res = _dwarf_fill_in_locdesc_op_c(dbg,
            i,
            rctx,
            &ldc->ld_opsblock,
            address_size, offset_size,
            rctx->ll_cuversion,
            ldc->ld_rawlow, ldc->ld_rawhigh,
            ldc->ld_lle_value,
            error);
        if (res != DW_DLV_OK) {
            return res;
        }
    }
    rctx->ll_bytes_total = bytescounttotal;
    return DW_DLV_OK;
}

/*  Build a head with all the relevent Entries
    attached, all the locdescs and for each such,
    all its expression operators.
*/
int
_dwarf_loclists_fill_in_lle_head(Dwarf_Debug dbg,
    Dwarf_Attribute attr,
    Dwarf_Loc_Head_c llhead,
    Dwarf_Error         *error)
{
    int res = 0;
    Dwarf_Unsigned loclists_contextnum = 0;
    Dwarf_Small *table_base = 0;
    Dwarf_Small *table_entry = 0;
    Dwarf_Small *enddata = 0;
    Dwarf_Loclists_Context *array = 0;
    Dwarf_Loclists_Context rctx = 0;
    Dwarf_Unsigned entrycount = 0;
    unsigned       offsetsize = 0;
    Dwarf_Unsigned   lle_global_offset = 0;
    Dwarf_CU_Context ctx = 0;
    Dwarf_Unsigned   offset_in_loclists = 0;
    Dwarf_Bool       is_loclistx = FALSE;
    Dwarf_Half       theform = llhead->ll_attrform;
    Dwarf_Bool       loclists_base_present =
        llhead->ll_at_loclists_base_present;
    Dwarf_Unsigned   loclists_base =
        llhead->ll_at_loclists_base;
    Dwarf_Unsigned   attr_val = 0;

    if (!attr) {
        _dwarf_error_string(NULL, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL "
            "NULL attribute "
            "argument passed to "
            "_dwarf_loclists_fill_in_lle_head()");
        return DW_DLV_ERROR;
    }
    ctx = attr->ar_cu_context;
    array = dbg->de_loclists_context;
    if (theform == DW_FORM_loclistx) {
        Dwarf_Bool offset_is_info   = 0;
        is_loclistx = TRUE;
        res = dwarf_global_formref_b(attr,
            &attr_val, &offset_is_info, error);
        if (res != DW_DLV_OK) {
            return res;
        }
    } else {
        if (theform == DW_FORM_sec_offset) {
            /*  DW_FORM_sec_offset is not formudata , often
                seen in in DW5 DW_AT_location etc */
            res = dwarf_global_formref(attr, &attr_val,error);
            if (res != DW_DLV_OK) {
                return res;
            }
        }
    }
    if (is_loclistx) {
        if (loclists_base_present) {
            offset_in_loclists = loclists_base;
        } else if (ctx->cc_is_dwo) {
            /* missing a  DW_AT_loclists_base! */
            /*  Generate a base and set as 'present'
            by looking at the location offset
            table that we are supposedly indexing into.
            finding what the table value is.
            An implicit loclists_base.
            Will not work with multiple loclists! */
            int ires = 0;
            Dwarf_Unsigned ibase = 0;
            ires = _dwarf_implicit_loclists_base(dbg,
                attr_val,&ibase);
            if (ires != DW_DLV_OK) {
                dwarfstring m;

                dwarfstring_constructor(&m);
                dwarfstring_append_printf_u(&m,
                    "DW_DLE_LOCLISTS_ERROR: loclists table"
                    " index of"
                    " %u"  ,attr_val);
                dwarfstring_append(&m,
                    " is unusable, there is no default "
                    " loclists base address ");
                _dwarf_error_string(dbg,error,
                    DW_DLE_LOCLISTS_ERROR,
                    dwarfstring_string(&m));
                dwarfstring_destructor(&m);
                return DW_DLV_ERROR;
            }
            ctx->cc_loclists_base_present = TRUE;
            ctx->cc_loclists_base         = ibase;
            offset_in_loclists = ibase;
        }
    } else {
        offset_in_loclists = attr_val;
    }
    res = _dwarf_which_loclists_context(dbg,ctx,
        offset_in_loclists,
        &loclists_contextnum,error);
    if (res != DW_DLV_OK) {
        return res;
    }
    rctx = array[loclists_contextnum];
    table_base = rctx->lc_offsets_array;
    entrycount = rctx->lc_offset_entry_count;
    offsetsize = rctx->lc_offset_size;
    enddata = rctx->lc_endaddr;

    if (is_loclistx) {
        if (attr_val >= entrycount) {
            dwarfstring m;

            dwarfstring_constructor(&m);
            dwarfstring_append_printf_u(&m,
                "DW_DLE_LOCLISTS_ERROR: loclists table index of"
                " %u"  ,attr_val);
            dwarfstring_append_printf_u(&m,
                " too large for table of %u "
                "entries.",entrycount);
            _dwarf_error_string(dbg,error,
                DW_DLE_LOCLISTS_ERROR,
                dwarfstring_string(&m));
            dwarfstring_destructor(&m);
            return DW_DLV_ERROR;
        }
    }
    llhead->ll_localcontext = rctx;
    llhead->ll_index = loclists_contextnum;
    llhead->ll_cuversion = rctx->lc_version;
    llhead->ll_offset_size = offsetsize;
    llhead->ll_address_size  = rctx->lc_address_size;
    llhead->ll_segment_selector_size =
        rctx->lc_segment_selector_size;

    if (is_loclistx) {
        Dwarf_Unsigned table_entryval = 0;

        table_entry = attr_val*offsetsize + table_base;
        /*  No malloc here yet so no leak if the macro returns
            DW_DLV_ERROR */
        READ_UNALIGNED_CK(dbg,table_entryval, Dwarf_Unsigned,
            table_entry,offsetsize,error,enddata);
        lle_global_offset = rctx->lc_offsets_off_in_sect +
            table_entryval;
    } else {
        lle_global_offset = attr_val;
    }
    llhead->ll_end_data_area = enddata;

    llhead->ll_llearea_offset = lle_global_offset;
    llhead->ll_llepointer = lle_global_offset +
        dbg->de_debug_loclists.dss_data;

    res = build_array_of_lle(dbg,llhead,error);
    if (res != DW_DLV_OK) {
        return res;
    }
    return DW_DLV_OK;
}

#if 0 /* candidate for public api?. No, not usable. */
int
dwarf_get_loclists_entry_fields(
    Dwarf_Loc_Head_c head,
    Dwarf_Unsigned entrynum,
    unsigned *entrylen,
    unsigned *code,
    Dwarf_Unsigned *raw1,
    Dwarf_Unsigned *raw2,
    Dwarf_Unsigned *cooked1,
    Dwarf_Unsigned *cooked2,
    Dwarf_Unsigned *lle_bytesize;
    /*  FIXME not right for loclists or their loc exprs */
    Dwarf_Error *error)
{
    Dwarf_Locdesc_c e = 0;
    if (!head || head->ll_magic != LOCLISTS_MAGIC) {
        _dwarf_error_string(NULL, error,DW_DLE_DBG_NULL,
            "DW_DLE_DBG_NULL"
            "NULL Dwarf_Loc_Head_c "
            " not set with LOCLISTS_MAGIC in "
            "argument passed to "
            "dwarf_get_loclist_entry_fields()");
        return DW_DLV_ERROR;
    }

    if (entrynum >= head->ll_locdesc_count) {
        return DW_DLV_NO_ENTRY;
    }
    e = head->ll_locdesc + entrynum;
    *entrylen  = e->ld_entrylen;
    *code      = e->ld_lle_value;
    *lle_bytesize = e->ld_lle_value /* bogus */;
    *raw1      = e->ld_rawlow;
    *raw2      = e->ld_rawhigh;
    *cooked1   = e->ld_lopc;
    *cooked2   = e->ld_highpc;
    return DW_DLV_OK;
}
#endif /*0*/

static void
_dwarf_free_loclists_limited_head_content(Dwarf_Loc_Head_c head)
{
    if (head->ll_first) {
        /* partially built head. */
        /*  ASSERT: ll_loclists is NULL */
        Dwarf_Locdesc_c cur = head->ll_first;
        Dwarf_Locdesc_c next = 0;

        for ( ; cur ; cur = next) {
            next = cur->ld_next;
            cur->ld_next = 0;
            cur->ld_magic = 0;
            free(cur);
        }
        head->ll_first = 0;
        head->ll_last = 0;
        head->ll_locdesc_count = 0;
    }
}
/*  Deals with both fully and partially build head,
    called by user calls to clean up or by
    libdwarf to clean up on error.  */
void
dwarf_dealloc_loc_head_c(Dwarf_Loc_Head_c head)
{
    Dwarf_Debug dbg =  0;

    if (!head) {
        return;
    }
    if (head->ll_magic != LOCLISTS_MAGIC) {
        return;
    }
    dbg = head->ll_dbg;
    if (IS_INVALID_DBG(dbg)) {
        return;
    }
    if (head->ll_first) {
        _dwarf_free_loclists_limited_head_content(head);
    }
    if (head->ll_locdesc) {
        Dwarf_Locdesc_c desc = head->ll_locdesc;
        /*  ASSERT: ll_first and ll_last are NULL */
        /* fully built head. */
        Dwarf_Unsigned listlen = head->ll_locdesc_count;
        Dwarf_Unsigned i = 0;

        /*  It's an array of desc. */
        for ( ; i < listlen; ++i) {
            Dwarf_Loc_Expr_Op loc = desc[i].ld_s;
            if (loc) {
                dwarf_dealloc(dbg,loc,DW_DLA_LOC_BLOCK_C);
                desc[i].ld_s = 0;
            }
        }
        /*  It is an array of structs,
            and the block in each is gone.
            It will be a simple single free. */
        dwarf_dealloc(dbg,head->ll_locdesc,DW_DLA_LOCDESC_C);
        head->ll_locdesc_count = 0;
        head->ll_locdesc = 0;
    }
    dwarf_dealloc(dbg,head,DW_DLA_LOC_HEAD_C);
}

/*  dwarf_alloc calls this on dealloc. head is freed there
    after this returns. */
void
_dwarf_loclists_head_destructor(void *head)
{
    Dwarf_Loc_Head_c h = head;

    _dwarf_free_loclists_limited_head_content(h);
}
