/* Another try at encapsulating bsd object files in coff. Copyright (C) 1988, 1989, 1991 Free Software Foundation, Inc. Written by Pace Willisson 12/9/88 This file is obsolete. It needs to be converted to just define a bunch of stuff that BFD can use to do coff-encapsulated files. --gnu@cygnus.com 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. */ /* * This time, we will only use the coff headers to tell the kernel * how to exec the file. Therefore, the only fields that need to * be filled in are the scnptr and vaddr for the text and data * sections, and the vaddr for the bss. As far as coff is concerned, * there is no symbol table, relocation, or line numbers. * * A normal bsd header (struct exec) is placed after the coff headers, * and before the real text. I defined a the new fields 'a_machtype' * and a_flags. If a_machtype is M_386, and a_flags & A_ENCAP is * true, then the bsd header is preceeded by a coff header. Macros * like N_TXTOFF and N_TXTADDR use this field to find the bsd header. * * The only problem is to track down the bsd exec header. The * macros HEADER_OFFSET, etc do this. Look at nm.c, dis.c, etc * for examples. */ #ifndef A_OUT_ENCAP_H_SEEN #define A_OUT_ENCAP_H_SEEN #include "a.out.gnu.h" #define N_FLAGS_COFF_ENCAPSULATE 0x20 /* coff header precedes bsd header */ /* Describe the COFF header used for encapsulation. */ struct coffheader { /* filehdr */ unsigned short f_magic; unsigned short f_nscns; long f_timdat; long f_symptr; long f_nsyms; unsigned short f_opthdr; unsigned short f_flags; /* aouthdr */ short magic; short vstamp; long tsize; long dsize; long bsize; long entry; long text_start; long data_start; struct coffscn { char s_name[8]; long s_paddr; long s_vaddr; long s_size; long s_scnptr; long s_relptr; long s_lnnoptr; unsigned short s_nreloc; unsigned short s_nlnno; long s_flags; } scns[3]; /* text, data, bss */ }; /* Describe some of the parameters of the encapsulation, including how to find the encapsulated BSD header. */ #if TARGET == TARGET_I386 #define COFF_MAGIC 0514 /* I386MAGIC */ #endif #if TARGET == TARGET_M68K #define COFF_MAGIC 0520 /* MC68MAGIC */ #endif #if TARGET == TARGET_SPARC #define COFF_MAGIC UNKNOWN!!! /* Used by TTI */ #endif #if TARGET == TARGET_AM29K #define COFF_MAGIC 0x17A /* Used by asm29k cross-tools */ #endif #ifdef COFF_MAGIC short __header_offset_temp; /* FIXME, this is dumb. The same tools can't handle a.outs for different architectures, just because COFF_MAGIC is different; so you need a separate GNU nm for every architecture!!? Also note that for expediency, this macros accepts COFF_MAGIC in either byte order. The right thing to do is to call read_aout_header to handle all this. */ #define HEADER_OFFSET(f) \ (__header_offset_temp = 0, \ fread ((char *)&__header_offset_temp, sizeof (short), 1, (f)), \ fseek ((f), -sizeof (short), 1), \ (__header_offset_temp==COFF_MAGIC || __header_offset_temp == \ ((COFF_MAGIC >> 8)|((COFF_MAGIC&0xFF)<<8)) \ ? sizeof(struct coffheader) : 0)) #define HEADER_OFFSET_FD(fd) \ (__header_offset_temp = 0, \ read (fd, (char *)&__header_offset_temp, sizeof (short)), \ lseek ((fd), -sizeof (short), 1), \ (__header_offset_temp==COFF_MAGIC || __header_offset_temp == \ ((COFF_MAGIC >> 8)|((COFF_MAGIC&0xFF)<<8)) \ ? sizeof(struct coffheader) : 0)) #else #define HEADER_OFFSET(f) 0 #define HEADER_OFFSET_FD(fd) 0 #endif #define HEADER_SEEK(f) (fseek ((f), HEADER_OFFSET((f)), 1)) #define HEADER_SEEK_FD(fd) (lseek ((fd), HEADER_OFFSET_FD((fd)), 1)) /* Describe the characteristics of the BSD header that appears inside the encapsulation. */ #undef _N_HDROFF #undef N_TXTADDR #undef N_DATADDR /* Encapsulated coff files that are linked ZMAGIC have a text segment offset just past the header (and a matching TXTADDR), excluding the headers from the text segment proper but keeping the physical layout and the virtual memory layout page-aligned. Non-encapsulated a.out files that are linked ZMAGIC have a text segment that starts at 0 and an N_TXTADR similarly offset to 0. They too are page-aligned with each other, but they include the a.out header as part of the text. The _N_HDROFF gets sizeof struct exec added to it, so we have to compensate here. See <a.out.gnu.h>. */ #define _N_HDROFF(x) ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ sizeof (struct coffheader) : -sizeof (struct exec)) /* Address of text segment in memory after it is loaded. */ #define N_TXTADDR(x) \ (TEXT_START_ADDR + \ ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ sizeof (struct coffheader) + sizeof (struct exec) : 0)) /* I have no idea what this is doing here. -- gnu@toad.com 20Mar90 Perhaps it is to give a size that is acceptable to any machine? */ #undef SEGMENT_SIZE #define SEGMENT_SIZE 0x400000 #define N_DATADDR(x) \ ((N_FLAGS(x) & N_FLAGS_COFF_ENCAPSULATE) ? \ (SEGMENT_SIZE + ((N_TXTADDR(x)+(x).a_text-1) & ~(SEGMENT_SIZE-1))) : \ (N_TXTADDR(x)+(x).a_text)) #endif /* A_OUT_ENCAP_H_SEEN */