133965Sjdp/* Yet Another Try at encapsulating bsd object files in coff. 278828Sobrien Copyright 1988, 1989, 1991 Free Software Foundation, Inc. 333965Sjdp Written by Pace Willisson 12/9/88 433965Sjdp 533965Sjdp This file is obsolete. It needs to be converted to just define a bunch 633965Sjdp of stuff that BFD can use to do coff-encapsulated files. --gnu@cygnus.com 733965Sjdp 833965SjdpThis program is free software; you can redistribute it and/or modify 933965Sjdpit under the terms of the GNU General Public License as published by 1033965Sjdpthe Free Software Foundation; either version 2 of the License, or 1133965Sjdp(at your option) any later version. 1233965Sjdp 1333965SjdpThis program is distributed in the hope that it will be useful, 1433965Sjdpbut WITHOUT ANY WARRANTY; without even the implied warranty of 1533965SjdpMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1633965SjdpGNU General Public License for more details. 1733965Sjdp 1833965SjdpYou should have received a copy of the GNU General Public License 1933965Sjdpalong with this program; if not, write to the Free Software 20218822SdimFoundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 2133965Sjdp 2233965Sjdp/* 2333965Sjdp * We only use the coff headers to tell the kernel 2433965Sjdp * how to exec the file. Therefore, the only fields that need to 2533965Sjdp * be filled in are the scnptr and vaddr for the text and data 2633965Sjdp * sections, and the vaddr for the bss. As far as coff is concerned, 2733965Sjdp * there is no symbol table, relocation, or line numbers. 2833965Sjdp * 2933965Sjdp * A normal bsd header (struct exec) is placed after the coff headers, 3033965Sjdp * and before the real text. I defined a the new fields 'a_machtype' 3133965Sjdp * and a_flags. If a_machtype is M_386, and a_flags & A_ENCAP is 3233965Sjdp * true, then the bsd header is preceeded by a coff header. Macros 3333965Sjdp * like N_TXTOFF and N_TXTADDR use this field to find the bsd header. 3433965Sjdp * 3533965Sjdp * The only problem is to track down the bsd exec header. The 3633965Sjdp * macros HEADER_OFFSET, etc do this. 3733965Sjdp */ 3833965Sjdp 3933965Sjdp#define N_FLAGS_COFF_ENCAPSULATE 0x20 /* coff header precedes bsd header */ 4033965Sjdp 4133965Sjdp/* Describe the COFF header used for encapsulation. */ 4233965Sjdp 4333965Sjdpstruct coffheader 4433965Sjdp{ 4533965Sjdp /* filehdr */ 4633965Sjdp unsigned short f_magic; 4733965Sjdp unsigned short f_nscns; 4833965Sjdp long f_timdat; 4933965Sjdp long f_symptr; 5033965Sjdp long f_nsyms; 5133965Sjdp unsigned short f_opthdr; 5233965Sjdp unsigned short f_flags; 5333965Sjdp /* aouthdr */ 5433965Sjdp short magic; 5533965Sjdp short vstamp; 5633965Sjdp long tsize; 5733965Sjdp long dsize; 5833965Sjdp long bsize; 5933965Sjdp long entry; 6033965Sjdp long text_start; 6133965Sjdp long data_start; 6233965Sjdp struct coffscn 6333965Sjdp { 6433965Sjdp char s_name[8]; 6533965Sjdp long s_paddr; 6633965Sjdp long s_vaddr; 6733965Sjdp long s_size; 6833965Sjdp long s_scnptr; 6933965Sjdp long s_relptr; 7033965Sjdp long s_lnnoptr; 7133965Sjdp unsigned short s_nreloc; 7233965Sjdp unsigned short s_nlnno; 7333965Sjdp long s_flags; 7433965Sjdp } scns[3]; 7533965Sjdp}; 7633965Sjdp 7733965Sjdp/* Describe some of the parameters of the encapsulation, 7833965Sjdp including how to find the encapsulated BSD header. */ 7933965Sjdp 8033965Sjdp/* FIXME, this is dumb. The same tools can't handle a.outs for different 8133965Sjdp architectures, just because COFF_MAGIC is different; so you need a 8233965Sjdp separate GNU nm for every architecture!!? Unfortunately, it needs to 8333965Sjdp be this way, since the COFF_MAGIC value is determined by the kernel 8433965Sjdp we're trying to fool here. */ 8533965Sjdp 8633965Sjdp#define COFF_MAGIC_I386 0514 /* I386MAGIC */ 8733965Sjdp#define COFF_MAGIC_M68K 0520 /* MC68MAGIC */ 8833965Sjdp 8933965Sjdp#ifdef COFF_MAGIC 9033965Sjdpshort __header_offset_temp; 9133965Sjdp#define HEADER_OFFSET(f) \ 9233965Sjdp (__header_offset_temp = 0, \ 9333965Sjdp fread ((char *)&__header_offset_temp, sizeof (short), 1, (f)), \ 9433965Sjdp fseek ((f), -sizeof (short), 1), \ 9533965Sjdp __header_offset_temp==COFF_MAGIC ? sizeof(struct coffheader) : 0) 9633965Sjdp#else 9733965Sjdp#define HEADER_OFFSET(f) 0 9833965Sjdp#endif 9933965Sjdp 10033965Sjdp#define HEADER_SEEK(f) (fseek ((f), HEADER_OFFSET((f)), 1)) 10133965Sjdp 10233965Sjdp/* Describe the characteristics of the BSD header 10333965Sjdp that appears inside the encapsulation. */ 10433965Sjdp 10533965Sjdp/* Encapsulated coff files that are linked ZMAGIC have a text segment 10633965Sjdp offset just past the header (and a matching TXTADDR), excluding 10733965Sjdp the headers from the text segment proper but keeping the physical 10833965Sjdp layout and the virtual memory layout page-aligned. 10933965Sjdp 11033965Sjdp Non-encapsulated a.out files that are linked ZMAGIC have a text 11133965Sjdp segment that starts at 0 and an N_TXTADR similarly offset to 0. 11233965Sjdp They too are page-aligned with each other, but they include the 11333965Sjdp a.out header as part of the text. 11433965Sjdp 11533965Sjdp The _N_HDROFF gets sizeof struct exec added to it, so we have 11633965Sjdp to compensate here. See <a.out.gnu.h>. */ 11733965Sjdp 11833965Sjdp#undef _N_HDROFF 11933965Sjdp#undef N_TXTADDR 12033965Sjdp#undef N_DATADDR 12133965Sjdp 12233965Sjdp#define _N_HDROFF(x) ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ 12333965Sjdp sizeof (struct coffheader) : 0) 12433965Sjdp 12533965Sjdp/* Address of text segment in memory after it is loaded. */ 12633965Sjdp#define N_TXTADDR(x) \ 12733965Sjdp ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ 12833965Sjdp sizeof (struct coffheader) + sizeof (struct exec) : 0) 12933965Sjdp#define SEGMENT_SIZE 0x400000 13033965Sjdp 13133965Sjdp#define N_DATADDR(x) \ 13233965Sjdp ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ 13333965Sjdp (SEGMENT_SIZE + ((N_TXTADDR(x)+(x).a_text-1) & ~(SEGMENT_SIZE-1))) : \ 13433965Sjdp (N_TXTADDR(x)+(x).a_text)) 135