{ Copyright (c) 2002 by Daniel Mantione, Peter Vreman Contains the binary reader and writer for the linear executable format used by OS/2 * 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 oglx; {$i fpcdefs.inc} interface uses { common } cclasses, { target } systems, { assembler } cpubase,aasmbase,assemble,link, { output } ogbase,ogmap,ogcoff; { An LX executable is called a module; it can be either an executable or a DLL. A module consists of objects. In other executable formats, these are usually called sections. Objects consist of pages. The objects are numbered, numbers do not have any special meaning. The pages of the object are loaded into memory with the access rights specified the object table entry. (DM)} { For the operating system the object numbers have no special meaning. However, for Free Pascal generated executables, I define: (DM)} const code_object = 0; data_object = 1; bss_object = 2; stack_object = 3; heap_object = 4; type Tlxheader = packed record magic:word; {'LX'} byteorder:byte; {0 = little 1 = big endian.} wordorder:byte; {0 = little 1 = big endian.} format_level:cardinal; {Nothing else than LX level 0 has ever been defined.} cpu_type:word; {1 = 286, 2 = 386, 3 = 486, 4 = pentium.} os_type:word; {1 = OS/2, 2 = Windows, 3 = Siemens MS-Dos 4.0, 4 = Windows 386.} module_version:cardinal; {Version of executable, defined by user.} module_flags:cardinal; {Flags.} module_page_count:cardinal; {Amount of pages in module.} eip_object,eip:cardinal; {Initial EIP, object nr and offset within object.} esp_object,esp:cardinal; {Initial ESP, object nr and offset within object.} page_size,page_shift:cardinal; {Page size, in bytes and 1 << pageshift.} fixup_sect_size:cardinal; fixup_sect_checksum:cardinal; loader_sect_size:cardinal; loader_sect_chksum:cardinal; object_table_offset:cardinal; {Location of object table.} object_count:cardinal; {Amount of objects in module.} object_pagetable_ofs:cardinal; {Location of object page table.} object_iterpages_ofs:cardinal; resource_table_ofs:cardinal; {Location of resource table.} resource_count:cardinal; {Amount of resources in resource table.} resid_name_tbl_ofs:cardinal; entry_table_offset:cardinal; module_dir_offset:cardinal; module_dir_count:cardinal; fixup_pagetab_ofs:cardinal; fixup_recrab_ofs:cardinal; import_modtab_ofs:cardinal; import_modtab_count:cardinal; data_pages_offset:cardinal; preload_page_count:cardinal; nonresid_table_ofs:cardinal; nonresid_table_len:cardinal; nonresid_tbl_chksum:cardinal; auto_ds_object_no:cardinal; {Not used by OS/2.} debug_info_offset:cardinal; inst_preload_count:cardinal; inst_demand_count:cardinal; heapsize:cardinal; {Only used for 16-bit programs.} end; Tlxobject_flags = (ofreadable,ofwriteable,ofexecutable,ofresource, ofdiscardable,ofshared,ofpreload,ofinvalid, ofzerofilled); Tlxobject_flag_set = set of Tlxobject_flags; Tlxobject_table_entry = packed record virtual_size:cardinal; reloc_base_addr:cardinal; object_flags:Tlxobject_flag_set; page_table_index:cardinal; page_count:cardinal; reserved:cardinal; end; Tlxexeoutput = class(texeoutput) private { FCoffsyms, FCoffStrs : tdynamicarray; win32 : boolean;} nsects, nsyms, sympos : longint; procedure write_symbol(const name:string;strpos,value,section,typ,aux:longint); procedure write_symbols; protected function writedata:boolean;override; public constructor createos2; function newobjectinput:tobjectinput;override; procedure CalculateMemoryMap;override; procedure GenerateExecutable(const fn:string);override; end; Tlxlinker = class(tinternallinker) constructor create;override; end; implementation uses strings, cutils,verbose, globtype,globals,fmodule, owar; {**************************************************************************** tcoffexeoutput ****************************************************************************} constructor Tlxexeoutput.createos2; begin inherited create; end; function Tlxexeoutput.newobjectinput:tobjectinput; begin result:=tcoffobjectinput.createdjgpp; end; procedure Tlxexeoutput.write_symbol(const name:string;strpos,value,section,typ,aux:longint); { var sym : coffsymbol;} begin { FillChar(sym,sizeof(sym),0); if strpos=-1 then move(name[1],sym.name,length(name)) else sym.strpos:=strpos; sym.value:=value; sym.section:=section; sym.typ:=typ; sym.aux:=aux; FWriter.write(sym,sizeof(sym));} end; procedure Tlxexeoutput.write_symbols; { var filename : string[18]; sec : TSection; namestr : string[8]; nameidx, value, sectionval, i : longint; globalval : byte; secrec : coffsectionrec; objdata : TObjData; p : tasmsymbol; s : string;} begin (* objdata:=TObjData(objdatalist.first); while assigned(objdata) do begin with tcoffObjData(objdata) do begin { The symbols used } p:=Tasmsymbol(symbols.First); while assigned(p) do begin if p.section=sec_common then sectionval:=sections[sec_bss].secsymidx else sectionval:=sections[p.section].secsymidx; if p.currbind=AB_LOCAL then globalval:=3 else globalval:=2; { if local of global then set the section value to the address of the symbol } if p.currbind in [AB_LOCAL,AB_GLOBAL] then value:=p.address else value:=p.size; { symbolname } s:=p.name; if length(s)>8 then begin nameidx:=FCoffStrs.size+4; FCoffStrs.writestr(s); FCoffStrs.writestr(#0); end else begin nameidx:=-1; namestr:=s; end; write_symbol(namestr,nameidx,value,sectionval,globalval,0); p:=tasmsymbol(p.indexnext); end; end; objdata:=TObjData(objdata.next); end;*) end; procedure Tlxexeoutput.CalculateMemoryMap; { var objdata : TObjData; secsymidx, mempos, datapos : longint; sec : TSection; sym : tasmsymbol; s : TObjSection;} begin (* { retrieve amount of sections } nsects:=0; secsymidx:=0; for sec:=low(TSection) to high(TSection) do begin if sections[sec].available then begin inc(nsects); inc(secsymidx); sections[sec].secsymidx:=secsymidx; end; end; { calculate start positions after the headers } datapos:=sizeof(coffheader)+sizeof(coffoptheader)+sizeof(coffsechdr)*nsects; mempos:=sizeof(coffheader)+sizeof(coffoptheader)+sizeof(coffsechdr)*nsects; if not win32 then inc(mempos,sizeof(go32v2stub)+$1000); { add sections } MapObjData(datapos,mempos); { end symbol } AddGlobalSym('_etext',sections[sec_code].mempos+sections[sec_code].memsize); AddGlobalSym('_edata',sections[sec_data].mempos+sections[sec_data].memsize); AddGlobalSym('end',mempos); { symbols } nsyms:=0; sympos:=0; if not(cs_link_strip in current_settings.globalswitches) then begin sympos:=datapos; objdata:=TObjData(objdatalist.first); while assigned(objdata) do begin inc(nsyms,objdata.symbols.count); objdata:=TObjData(objdata.next); end; end;*) end; function gen_section_header(sec:Tsection;obj:cardinal):Tlxobject_table_entry; virtual_size:cardinal; reloc_base_addr:cardinal; object_flags:Tlxobject_flag_set; page_table_index:cardinal; page_count:cardinal; reserved:cardinal; begin gen_section_header.virtual_size:=sections[sec.memsize]; end; function Tlxexeoutput.writedata:boolean; var header:Tlxheader; hsym:Tasmsymbol; code_object_header,data_object_header,bss_object_header,stack_object_header, heap_object_header:Tlxobject_table_entry; begin result:=false; fillchar(header,sizeof(header),0); header.magic:=$584c; {'LX'} header.cpu_type:=2; {Intel 386} header.os_type:=1; {OS/2} {Set the initial EIP.} header.eip_object:=code_object; hsym:=tasmsymbol(globalsyms.Find('start')); if not assigned(hsym) then begin comment(V_Error,'Entrypoint "start" not defined'); exit; end; header.eip:=hsym.address-sections[sec_code].mempos; {Set the initial ESP.} header.esp_object:=stack_object; header.esp:=stacksize; Fwriter.write(header,sizeof(header)); for sec:=low(Tsection) to high(Tsection) do if sections[sec].available then if not(sec in [sec_code,sec_data,sec_bss,sec_stab,sec_stabstr]) then begin result:=false; exit; end; code_object_header:=gen_section_header(sec_code,code_object); data_object_header:=gen_section_header(sec_data,data_object); bss_object_header:=gen_section_header(sec_bss,bss_object); result:=true; end; procedure Tlxexeoutput.GenerateExecutable(const fn:string); begin { AddGlobalSym('_etext',0); AddGlobalSym('_edata',0); AddGlobalSym('end',0); if not CalculateSymbols then exit; CalculateMemoryMap; FixupSymbols; FixupRelocations; writeexefile(fn);} end; {**************************************************************************** TCoffLinker ****************************************************************************} constructor Tlxlinker.Create; begin inherited Create; CArObjectReader:=TArObjectReader; exeoutput:=Tlxexeoutput.createos2; end; {***************************************************************************** Initialize *****************************************************************************} begin { RegisterAssembler(as_i386_coff_info,TCoffAssembler); RegisterAssembler(as_i386_pecoff_info,TPECoffAssembler); RegisterAssembler(as_i386_pecoffwdosx_info,TPECoffAssembler); RegisterLinker(ld_i386_coff,Tlxlinker);} end.