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|
{
$Id: ogelf.pas,v 1.25 2005/02/14 17:13:06 peter Exp $
Copyright (c) 1998-2002 by Peter Vreman
Contains the binary elf writer
* This code was inspired by the NASM sources
The Netwide Assembler is Copyright (c) 1996 Simon Tatham and
Julian Hall. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
****************************************************************************
}
unit ogelf;
{$i fpcdefs.inc}
interface
uses
{ common }
cclasses,globtype,
{ target }
systems,
{ assembler }
cpuinfo,cpubase,aasmbase,aasmtai,assemble,
{ output }
ogbase;
type
telf32section = class(TAsmSection)
public
secshidx : longint; { index for the section in symtab }
shstridx,
shtype,
shflags,
shlink,
shinfo,
entsize : longint;
{ relocation }
relocsect : telf32Section;
constructor create(const Aname:string;Atype:TAsmSectionType;Aalign:longint;Aoptions:TAsmSectionOptions);override;
constructor create_ext(const Aname:string;Atype:TAsmSectionType;Ashtype,Ashflags,Ashlink,Ashinfo,Aalign,Aentsize:longint);
destructor destroy;override;
end;
telf32objectdata = class(TAsmObjectData)
public
symtabsect,
strtabsect,
shstrtabsect,
gotpcsect,
gotoffsect,
goTSect,
plTSect,
symsect : telf32Section;
syms : Tdynamicarray;
constructor create(const n:string);
destructor destroy;override;
function sectionname(atype:tasmsectiontype;const aname:string):string;override;
procedure writereloc(data,len:aint;p:tasmsymbol;relative:TAsmRelocationType);override;
procedure writesymbol(p:tasmsymbol);override;
procedure writestabs(offset:aint;p:pchar;nidx,nother,line:longint;reloc:boolean);override;
procedure writesymstabs(offset:aint;p:pchar;ps:tasmsymbol;nidx,nother,line:longint;reloc:boolean);override;
procedure beforealloc;override;
procedure beforewrite;override;
end;
telf32objectoutput = class(tobjectoutput)
private
elf32data : telf32objectdata;
initsym : longint;
procedure createrelocsection(s:telf32section);
procedure createshstrtab;
procedure createsymtab;
procedure writesectionheader(s:telf32section);
procedure writesectiondata(s:telf32section);
procedure section_write_symbol(p:tnamedindexitem;arg:pointer);
procedure section_write_sh_string(p:tnamedindexitem;arg:pointer);
procedure section_number_symbol(p:tnamedindexitem;arg:pointer);
procedure section_count_sects(p:tnamedindexitem;arg:pointer);
procedure section_create_relocsec(p:tnamedindexitem;arg:pointer);
procedure section_set_datapos(p:tnamedindexitem;arg:pointer);
procedure section_relocsec_set_datapos(p:tnamedindexitem;arg:pointer);
procedure section_write_data(p:tnamedindexitem;arg:pointer);
procedure section_write_sechdr(p:tnamedindexitem;arg:pointer);
procedure section_write_relocsec(p:tnamedindexitem;arg:pointer);
protected
function writedata(data:TAsmObjectData):boolean;override;
public
function newobjectdata(const n:string):TAsmObjectData;override;
end;
telf32assembler = class(tinternalassembler)
constructor create(smart:boolean);override;
end;
implementation
uses
strings,
verbose,
cutils,globals,fmodule;
const
symbolresize = 200*18;
const
R_386_32 = 1; { ordinary absolute relocation }
R_386_PC32 = 2; { PC-relative relocation }
R_386_GOT32 = 3; { an offset into GOT }
R_386_PLT32 = 4; { a PC-relative offset into PLT }
R_386_GOTOFF = 9; { an offset from GOT base }
R_386_GOTPC = 10; { a PC-relative offset _to_ GOT }
SHN_UNDEF = 0;
SHN_ABS = $fff1;
SHN_COMMON = $fff2;
SHT_NULL = 0;
SHT_PROGBITS = 1;
SHT_SYMTAB = 2;
SHT_STRTAB = 3;
SHT_RELA = 4;
SHT_HASH = 5;
SHT_DYNAMIC = 6;
SHT_NOTE = 7;
SHT_NOBITS = 8;
SHT_REL = 9;
SHT_SHLIB = 10;
SHT_DYNSYM = 11;
SHF_WRITE = 1;
SHF_ALLOC = 2;
SHF_EXECINSTR = 4;
STB_LOCAL = 0;
STB_GLOBAL = 1;
STB_WEAK = 2;
STT_NOTYPE = 0;
STT_OBJECT = 1;
STT_FUNC = 2;
STT_SECTION = 3;
STT_FILE = 4;
type
{ Structures which are written directly to the output file }
telf32header=packed record
magic0123 : longint;
file_class : byte;
data_encoding : byte;
file_version : byte;
padding : array[$07..$0f] of byte;
e_type : word;
e_machine : word;
e_version : longint;
e_entry : longint; { entrypoint }
e_phoff : longint; { program header offset }
e_shoff : longint; { sections header offset }
e_flags : longint;
e_ehsize : word; { elf header size in bytes }
e_phentsize : word; { size of an entry in the program header array }
e_phnum : word; { 0..e_phnum-1 of entrys }
e_shentsize : word; { size of an entry in sections header array }
e_shnum : word; { 0..e_shnum-1 of entrys }
e_shstrndx : word; { index of string section header }
end;
telf32sechdr=packed record
sh_name : longint;
sh_type : longint;
sh_flags : longint;
sh_addr : longint;
sh_offset : longint;
sh_size : longint;
sh_link : longint;
sh_info : longint;
sh_addralign : longint;
sh_entsize : longint;
end;
telf32reloc=packed record
address : longint;
info : longint; { bit 0-7: type, 8-31: symbol }
end;
telf32symbol=packed record
st_name : longint;
st_value : longint;
st_size : longint;
st_info : byte; { bit 0-3: type, 4-7: bind }
st_other : byte;
st_shndx : word;
end;
telf32stab=packed record
strpos : longint;
ntype : byte;
nother : byte;
ndesc : word;
nvalue : longint;
end;
{****************************************************************************
TSection
****************************************************************************}
constructor telf32section.create(const Aname:string;Atype:TAsmSectionType;Aalign:longint;Aoptions:TAsmSectionOptions);
var
Ashflags,Ashtype,Aentsize : longint;
begin
Ashflags:=0;
Ashtype:=0;
Aentsize:=0;
case Atype of
sec_code :
begin
Ashflags:=SHF_ALLOC or SHF_EXECINSTR;
AshType:=SHT_PROGBITS;
AAlign:=max(sizeof(aint),AAlign);
end;
sec_data :
begin
Ashflags:=SHF_ALLOC or SHF_WRITE;
AshType:=SHT_PROGBITS;
AAlign:=max(sizeof(aint),AAlign);
end;
sec_bss :
begin
Ashflags:=SHF_ALLOC or SHF_WRITE;
AshType:=SHT_NOBITS;
AAlign:=max(sizeof(aint),AAlign);
end;
sec_stab :
begin
AshType:=SHT_PROGBITS;
AAlign:=max(sizeof(aint),AAlign);
Aentsize:=sizeof(telf32stab);
end;
sec_stabstr :
begin
AshType:=SHT_STRTAB;
AAlign:=1;
end;
end;
create_ext(Aname,Atype,Ashtype,Ashflags,0,0,Aalign,Aentsize);
end;
constructor telf32section.create_ext(const Aname:string;Atype:TAsmSectionType;Ashtype,Ashflags,Ashlink,Ashinfo,Aalign,Aentsize:longint);
var
aoptions : TAsmSectionOptions;
begin
aoptions:=[];
if (AshType=SHT_NOBITS) then
include(aoptions,aso_alloconly);
inherited create(Aname,Atype,Aalign,aoptions);
secshidx:=0;
shstridx:=0;
shtype:=AshType;
shflags:=AshFlags;
shlink:=Ashlink;
shinfo:=Ashinfo;
entsize:=Aentsize;
relocsect:=nil;
end;
destructor telf32section.destroy;
begin
if assigned(relocsect) then
relocsect.free;
inherited destroy;
end;
{****************************************************************************
telf32objectdata
****************************************************************************}
constructor telf32objectdata.create(const n:string);
var
s : string;
begin
inherited create(n);
CAsmSection:=TElf32Section;
{ reset }
Syms:=TDynamicArray.Create(symbolresize);
{ default sections }
symtabsect:=telf32section.create_ext('.symtab',sec_custom,2,0,0,0,4,16);
strtabsect:=telf32section.create_ext('.strtab',sec_custom,3,0,0,0,1,0);
shstrtabsect:=telf32section.create_ext('.shstrtab',sec_custom,3,0,0,0,1,0);
{ insert the empty and filename as first in strtab }
strtabsect.writestr(#0);
strtabsect.writestr(SplitFileName(current_module.mainsource^)+#0);
{ we need at least the following sections }
createsection(sec_code,'',0,[]);
createsection(sec_data,'',0,[]);
createsection(sec_bss,'',0,[]);
{ create stabs sections if debugging }
if (cs_debuginfo in aktmoduleswitches) then
begin
stabssec:=createsection(sec_stab,'',0,[]);
stabstrsec:=createsection(sec_stabstr,'',0,[]);
end;
end;
destructor telf32objectdata.destroy;
begin
Syms.Free;
symtabsect.free;
strtabsect.free;
shstrtabsect.free;
inherited destroy;
end;
function telf32objectdata.sectionname(atype:tasmsectiontype;const aname:string):string;
const
secnames : array[tasmsectiontype] of string[12] = ('',
{$ifdef userodata}
'.text','.data','.rodata','.bss',
{$else userodata}
'.text','.data','.data','.bss',
{$endif userodata}
'common',
'.note',
'.stab','.stabstr',
'.idata$2','.idata$4','.idata$5','.idata$6','.idata$7','.edata',
'.eh_frame',
'.debug_frame'
);
begin
if use_smartlink_section and
(atype<>sec_bss) and
(aname<>'') then
result:='.gnu.linkonce'+copy(secnames[atype],1,2)+'.'+aname
else
result:=secnames[atype];
end;
procedure telf32objectdata.writesymbol(p:tasmsymbol);
begin
if currsec=nil then
internalerror(200403291);
{ already written ? }
if p.indexnr<>-1 then
exit;
{ calculate symbol index }
if (p.currbind<>AB_LOCAL) then
begin
{ insert the symbol in the local index, the indexarray
will take care of the numbering }
symbols.insert(p);
end
else
p.indexnr:=-2; { local }
end;
procedure telf32objectdata.writereloc(data,len:aint;p:tasmsymbol;relative:TAsmRelocationType);
var
symaddr : longint;
begin
if currsec=nil then
internalerror(200403292);
{$ifdef userodata}
if currsec.sectype in [sec_rodata,sec_bss] then
internalerror(200408252);
{$endif userodata}
if assigned(p) then
begin
{ real address of the symbol }
symaddr:=p.address;
{ Local symbols can be resolved already or need a section reloc }
if (p.currbind=AB_LOCAL) then
begin
{ For a relative relocation in the same section the
value can be calculated }
if (p.section=currsec) and
(relative=RELOC_RELATIVE) then
inc(data,symaddr-len-currsec.datasize)
else
begin
currsec.addsectionreloc(currsec.datasize,p.section,relative);
inc(data,symaddr);
end;
end
else
begin
writesymbol(p);
currsec.addsymreloc(currsec.datasize,p,relative);
if relative=RELOC_RELATIVE then
dec(data,len);
end;
end;
currsec.write(data,len);
end;
procedure telf32objectdata.writestabs(offset:aint;p:pchar;nidx,nother,line:longint;reloc : boolean);
var
stab : telf32stab;
begin
if reloc then
begin
if (offset=-1) then
begin
if currsec=nil then
offset:=0
else
offset:=currsec.datasize;
end;
end;
fillchar(stab,sizeof(telf32stab),0);
if assigned(p) and (p[0]<>#0) then
begin
stab.strpos:=stabstrsec.datasize;
stabstrsec.write(p^,strlen(p)+1);
end;
stab.ntype:=nidx;
stab.ndesc:=line;
stab.nother:=nother;
stab.nvalue:=offset;
stabssec.write(stab,sizeof(stab));
{ when the offset is not 0 then write a relocation, take also the
hdrstab into account with the offset }
if reloc then
stabssec.addsectionreloc(stabssec.datasize-4,currsec,RELOC_ABSOLUTE);
end;
procedure telf32objectdata.writesymstabs(offset:aint;p:pchar;ps:tasmsymbol;nidx,nother,line:longint;reloc:boolean);
var
stab : telf32stab;
begin
fillchar(stab,sizeof(telf32stab),0);
if assigned(p) and (p[0]<>#0) then
begin
stab.strpos:=stabstrsec.datasize;
stabstrsec.write(p^,strlen(p)+1);
end;
stab.ntype:=nidx;
stab.ndesc:=line;
stab.nother:=nother;
stab.nvalue:=0;
stabssec.write(stab,sizeof(stab));
{ when the offset is not 0 then write a relocation, take also the
hdrstab into account with the offset }
if reloc then
stabssec.addsymreloc(stabssec.datasize-4,ps,RELOC_ABSOLUTE);
end;
procedure telf32objectdata.beforealloc;
begin
{ create stabs sections if debugging }
if (cs_debuginfo in aktmoduleswitches) then
begin
StabsSec.Alloc(sizeof(telf32stab));
StabStrSec.Alloc(length(SplitFileName(current_module.mainsource^))+2);
end;
end;
procedure telf32objectdata.beforewrite;
var
s : string;
begin
{ create stabs sections if debugging }
if (cs_debuginfo in aktmoduleswitches) then
begin
writestabs(0,nil,0,0,0,false);
{ write zero pchar and name together (PM) }
s:=#0+SplitFileName(current_module.mainsource^)+#0;
stabstrsec.write(s[1],length(s));
end;
end;
{****************************************************************************
telf32objectoutput
****************************************************************************}
function telf32objectoutput.newobjectdata(const n:string):TAsmObjectData;
begin
result:=telf32objectdata.create(n);
end;
procedure telf32objectoutput.createrelocsection(s:telf32section);
var
rel : telf32reloc;
r : tasmrelocation;
relsym,reltyp : longint;
begin
with elf32data do
begin
{$ifdef userodata}
{ rodata can't have relocations }
if s.sectype=sec_rodata then
begin
if assigned(s.relocations.first) then
internalerror(200408251);
exit;
end;
{$endif userodata}
{ create the reloc section }
s.relocsect:=telf32section.create_ext('.rel'+s.name,sec_custom,9,0,symtabsect.secshidx,s.secshidx,4,8);
{ add the relocations }
r:=TasmRelocation(s.relocations.first);
while assigned(r) do
begin
rel.address:=r.address;
if assigned(r.symbol) then
begin
if (r.symbol.currbind=AB_LOCAL) then
relsym:=r.symbol.section.secsymidx
else
begin
if r.symbol.indexnr=-1 then
internalerror(4321);
{ indexnr starts with 1, ELF starts with 0 }
relsym:=r.symbol.indexnr+initsym-1;
end;
end
else
if r.section<>nil then
relsym:=r.section.secsymidx
else
relsym:=SHN_UNDEF;
case r.typ of
RELOC_RELATIVE :
reltyp:=R_386_PC32;
RELOC_ABSOLUTE :
reltyp:=R_386_32;
end;
rel.info:=(relsym shl 8) or reltyp;
{ write reloc }
s.relocsect.write(rel,sizeof(rel));
r:=TAsmRelocation(r.next);
end;
end;
end;
procedure telf32objectoutput.section_write_symbol(p:tnamedindexitem;arg:pointer);
var
elfsym : telf32symbol;
begin
fillchar(elfsym,sizeof(elfsym),0);
elfsym.st_name:=telf32section(p).shstridx;
elfsym.st_info:=STT_SECTION;
elfsym.st_shndx:=telf32section(p).secshidx;
elf32data.symtabsect.write(elfsym,sizeof(elfsym));
{ increase locals count }
inc(plongint(arg)^);
end;
procedure telf32objectoutput.createsymtab;
var
elfsym : telf32symbol;
locals : longint;
sym : tasmsymbol;
begin
with elf32data do
begin
locals:=2;
{ empty entry }
fillchar(elfsym,sizeof(elfsym),0);
symtabsect.write(elfsym,sizeof(elfsym));
{ filename entry }
elfsym.st_name:=1;
elfsym.st_info:=STT_FILE;
elfsym.st_shndx:=SHN_ABS;
symtabsect.write(elfsym,sizeof(elfsym));
{ section }
sects.foreach(@section_write_symbol,@locals);
{ symbols }
sym:=Tasmsymbol(symbols.First);
while assigned(sym) do
begin
fillchar(elfsym,sizeof(elfsym),0);
{ symbolname, write the #0 separate to overcome 255+1 char not possible }
elfsym.st_name:=strtabsect.datasize;
strtabsect.writestr(sym.name);
strtabsect.writestr(#0);
case sym.currbind of
AB_LOCAL,
AB_GLOBAL :
elfsym.st_value:=sym.address;
AB_COMMON :
elfsym.st_value:=$10;
end;
elfsym.st_size:=sym.size;
case sym.currbind of
AB_LOCAL :
begin
elfsym.st_info:=STB_LOCAL shl 4;
inc(locals);
end;
AB_COMMON,
AB_EXTERNAL,
AB_GLOBAL :
elfsym.st_info:=STB_GLOBAL shl 4;
end;
if sym.currbind<>AB_EXTERNAL then
begin
case sym.typ of
AT_FUNCTION :
elfsym.st_info:=elfsym.st_info or STT_FUNC;
AT_DATA :
elfsym.st_info:=elfsym.st_info or STT_OBJECT;
end;
end;
if sym.currbind=AB_COMMON then
elfsym.st_shndx:=SHN_COMMON
else
if assigned(sym.section) then
elfsym.st_shndx:=telf32section(sym.section).secshidx
else
elfsym.st_shndx:=SHN_UNDEF;
symtabsect.write(elfsym,sizeof(elfsym));
sym:=tasmsymbol(sym.indexnext);
end;
{ update the .symtab section header }
symtabsect.shlink:=strtabsect.secshidx;
symtabsect.shinfo:=locals;
end;
end;
procedure telf32objectoutput.section_write_sh_string(p:tnamedindexitem;arg:pointer);
begin
telf32section(p).shstridx:=elf32data.shstrtabsect.writestr(tasmsection(p).name+#0);
if assigned(telf32section(p).relocsect) then
telf32section(p).relocsect.shstridx:=elf32data.shstrtabsect.writestr(telf32section(p).relocsect.name+#0);
end;
procedure telf32objectoutput.createshstrtab;
begin
with elf32data do
begin
with shstrtabsect do
begin
writestr(#0);
symtabsect.shstridx:=writestr('.symtab'#0);
strtabsect.shstridx:=writestr('.strtab'#0);
shstrtabsect.shstridx:=writestr('.shstrtab'#0);
sects.foreach(@section_write_sh_string,nil);
end;
end;
end;
procedure telf32objectoutput.writesectionheader(s:telf32section);
var
sechdr : telf32sechdr;
begin
fillchar(sechdr,sizeof(sechdr),0);
sechdr.sh_name:=s.shstridx;
sechdr.sh_type:=s.shtype;
sechdr.sh_flags:=s.shflags;
sechdr.sh_offset:=s.datapos;
sechdr.sh_size:=s.datasize;
sechdr.sh_link:=s.shlink;
sechdr.sh_info:=s.shinfo;
sechdr.sh_addralign:=s.addralign;
sechdr.sh_entsize:=s.entsize;
writer.write(sechdr,sizeof(sechdr));
end;
procedure telf32objectoutput.writesectiondata(s:telf32section);
var
hp : pdynamicblock;
begin
FWriter.writezeros(s.dataalignbytes);
s.alignsection;
hp:=s.data.firstblock;
while assigned(hp) do
begin
FWriter.write(hp^.data,hp^.used);
hp:=hp^.next;
end;
end;
procedure telf32objectoutput.section_number_symbol(p:tnamedindexitem;arg:pointer);
begin
tasmsection(p).secsymidx:=plongint(arg)^;
inc(plongint(arg)^);
end;
procedure telf32objectoutput.section_count_sects(p:tnamedindexitem;arg:pointer);
begin
telf32section(p).secshidx:=plongint(arg)^;
inc(plongint(arg)^);
if telf32section(p).relocations.count>0 then
inc(plongint(arg)^);
end;
procedure telf32objectoutput.section_create_relocsec(p:tnamedindexitem;arg:pointer);
begin
if (telf32section(p).relocations.count>0) then
createrelocsection(telf32section(p));
end;
procedure telf32objectoutput.section_set_datapos(p:tnamedindexitem;arg:pointer);
begin
if (aso_alloconly in tasmsection(p).secoptions) then
tasmsection(p).datapos:=paint(arg)^
else
tasmsection(p).setdatapos(paint(arg)^);
end;
procedure telf32objectoutput.section_relocsec_set_datapos(p:tnamedindexitem;arg:pointer);
begin
if assigned(telf32section(p).relocsect) then
telf32section(p).relocsect.setdatapos(paint(arg)^);
end;
procedure telf32objectoutput.section_write_data(p:tnamedindexitem;arg:pointer);
begin
if (aso_alloconly in tasmsection(p).secoptions) then
exit;
if tasmsection(p).data=nil then
internalerror(200403073);
writesectiondata(telf32section(p));
end;
procedure telf32objectoutput.section_write_sechdr(p:tnamedindexitem;arg:pointer);
begin
writesectionheader(telf32section(p));
if assigned(telf32section(p).relocsect) then
writesectionheader(telf32section(p).relocsect);
end;
procedure telf32objectoutput.section_write_relocsec(p:tnamedindexitem;arg:pointer);
begin
if assigned(telf32section(p).relocsect) then
writesectiondata(telf32section(p).relocsect);
end;
function telf32objectoutput.writedata(data:TAsmObjectData):boolean;
var
header : telf32header;
datapos : aint;
shoffset,
nsects : longint;
hstab : telf32stab;
empty : array[0..63] of byte;
begin
result:=false;
elf32data:=telf32objectdata(data);
with elf32data do
begin
{ calc amount of sections we have }
initsym:=2;
nsects:=1;
fillchar(empty,sizeof(empty),0);
{ each section requires a symbol for relocation }
sects.foreach(@section_number_symbol,@initsym);
{ also create the index in the section header table }
sects.foreach(@section_count_sects,@nsects);
{ add default sections follows }
shstrtabsect.secshidx:=nsects;
inc(nsects);
symtabsect.secshidx:=nsects;
inc(nsects);
strtabsect.secshidx:=nsects;
inc(nsects);
{ For the stab section we need an HdrSym which can now be
calculated more easily }
if assigned(stabssec) then
begin
hstab.strpos:=1;
hstab.ntype:=0;
hstab.nother:=0;
hstab.ndesc:=(stabssec.datasize div sizeof(telf32stab))-1{+1 according to gas output PM};
hstab.nvalue:=stabstrsec.datasize;
stabssec.Data.seek(0);
stabssec.Data.write(hstab,sizeof(hstab));
end;
{ Create the relocation sections }
sects.foreach(@section_create_relocsec,nil);
{ create .symtab and .strtab }
createsymtab;
{ create .shstrtab }
createshstrtab;
{ Calculate the filepositions }
datapos:=$40; { elfheader + alignment }
{ sections first }
sects.foreach(@section_set_datapos,@datapos);
{ shstrtab }
shstrtabsect.setdatapos(datapos);
{ section headers }
shoffset:=datapos;
inc(datapos,nsects*sizeof(telf32sechdr));
{ symtab }
symtabsect.setdatapos(datapos);
{ strtab }
strtabsect.setdatapos(datapos);
{ .rel sections }
sects.foreach(@section_relocsec_set_datapos,@datapos);
{ Write ELF Header }
fillchar(header,sizeof(header),0);
header.magic0123:=$464c457f; { = #127'ELF' }
header.file_class:=1;
header.data_encoding:=1;
header.file_version:=1;
header.e_type:=1;
header.e_machine:=3;
header.e_version:=1;
header.e_shoff:=shoffset;
header.e_shstrndx:=shstrtabsect.secshidx;
header.e_shnum:=nsects;
header.e_ehsize:=sizeof(telf32header);
header.e_shentsize:=sizeof(telf32sechdr);
writer.write(header,sizeof(header));
writer.write(empty,$40-sizeof(header)); { align }
{ Sections }
sects.foreach(@section_write_data,nil);
{ .shstrtab }
writesectiondata(shstrtabsect);
{ section headers, start with an empty header for sh_undef }
writer.write(empty,sizeof(telf32sechdr));
sects.foreach(@section_write_sechdr,nil);
writesectionheader(shstrtabsect);
writesectionheader(symtabsect);
writesectionheader(strtabsect);
{ .symtab }
writesectiondata(symtabsect);
{ .strtab }
writesectiondata(strtabsect);
{ .rel sections }
sects.foreach(@section_write_relocsec,nil);
end;
result:=true;
end;
{****************************************************************************
TELFAssembler
****************************************************************************}
constructor TELF32Assembler.Create(smart:boolean);
begin
inherited Create(smart);
objectoutput:=telf32objectoutput.create(smart);
end;
{*****************************************************************************
Initialize
*****************************************************************************}
const
as_i386_elf32_info : tasminfo =
(
id : as_i386_elf32;
idtxt : 'ELF';
asmbin : '';
asmcmd : '';
supported_target : system_any; //target_i386_linux;
// flags : [af_outputbinary,af_smartlink_sections];
flags : [af_outputbinary];
labelprefix : '.L';
comment : '';
);
initialization
RegisterAssembler(as_i386_elf32_info,TElf32Assembler);
end.
{
$Log: ogelf.pas,v $
Revision 1.25 2005/02/14 17:13:06 peter
* truncate log
Revision 1.24 2005/01/10 15:54:59 peter
* Cleanup of writing of relocations to symbols
* Only local symbols will now use a constant value or section relocation
}
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