1/* BFD back-end for MS-DOS executables. 2 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2001, 2002, 3 2003, 2004, 2005 Free Software Foundation, Inc. 4 Written by Bryan Ford of the University of Utah. 5 6 Contributed by the Center for Software Science at the 7 University of Utah (pa-gdb-bugs@cs.utah.edu). 8 9 This file is part of BFD, the Binary File Descriptor library. 10 11 This program is free software; you can redistribute it and/or modify 12 it under the terms of the GNU General Public License as published by 13 the Free Software Foundation; either version 2 of the License, or 14 (at your option) any later version. 15 16 This program is distributed in the hope that it will be useful, 17 but WITHOUT ANY WARRANTY; without even the implied warranty of 18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 GNU General Public License for more details. 20 21 You should have received a copy of the GNU General Public License 22 along with this program; if not, write to the Free Software 23 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 24 25 26#include "bfd.h" 27#include "sysdep.h" 28#include "libbfd.h" 29#include "libaout.h" 30 31#define EXE_MAGIC 0x5a4d 32#define EXE_LOAD_HIGH 0x0000 33#define EXE_LOAD_LOW 0xffff 34#define EXE_PAGE_SIZE 512 35 36static int msdos_sizeof_headers 37 PARAMS ((bfd *, bfd_boolean)); 38static bfd_boolean msdos_write_object_contents 39 PARAMS ((bfd *)); 40static bfd_boolean msdos_set_section_contents 41 PARAMS ((bfd *, sec_ptr, const PTR, file_ptr, bfd_size_type)); 42 43static int 44msdos_sizeof_headers (abfd, exec) 45 bfd *abfd ATTRIBUTE_UNUSED; 46 bfd_boolean exec ATTRIBUTE_UNUSED; 47{ 48 return 0; 49} 50 51static bfd_boolean 52msdos_write_object_contents (abfd) 53 bfd *abfd; 54{ 55 static char hdr[EXE_PAGE_SIZE]; 56 file_ptr outfile_size = sizeof(hdr); 57 bfd_vma high_vma = 0; 58 asection *sec; 59 60 /* Find the total size of the program on disk and in memory. */ 61 for (sec = abfd->sections; sec != (asection *) NULL; sec = sec->next) 62 { 63 if (sec->size == 0) 64 continue; 65 if (bfd_get_section_flags (abfd, sec) & SEC_ALLOC) 66 { 67 bfd_vma sec_vma = bfd_get_section_vma (abfd, sec) + sec->size; 68 if (sec_vma > high_vma) 69 high_vma = sec_vma; 70 } 71 if (bfd_get_section_flags (abfd, sec) & SEC_LOAD) 72 { 73 file_ptr sec_end = (sizeof (hdr) 74 + bfd_get_section_vma (abfd, sec) 75 + sec->size); 76 if (sec_end > outfile_size) 77 outfile_size = sec_end; 78 } 79 } 80 81 /* Make sure the program isn't too big. */ 82 if (high_vma > (bfd_vma)0xffff) 83 { 84 bfd_set_error(bfd_error_file_too_big); 85 return FALSE; 86 } 87 88 /* Constants. */ 89 H_PUT_16 (abfd, EXE_MAGIC, &hdr[0]); 90 H_PUT_16 (abfd, EXE_PAGE_SIZE / 16, &hdr[8]); 91 H_PUT_16 (abfd, EXE_LOAD_LOW, &hdr[12]); 92 H_PUT_16 (abfd, 0x3e, &hdr[24]); 93 H_PUT_16 (abfd, 0x0001, &hdr[28]); /* XXX??? */ 94 H_PUT_16 (abfd, 0x30fb, &hdr[30]); /* XXX??? */ 95 H_PUT_16 (abfd, 0x726a, &hdr[32]); /* XXX??? */ 96 97 /* Bytes in last page (0 = full page). */ 98 H_PUT_16 (abfd, outfile_size & (EXE_PAGE_SIZE - 1), &hdr[2]); 99 100 /* Number of pages. */ 101 H_PUT_16 (abfd, (outfile_size + EXE_PAGE_SIZE - 1) / EXE_PAGE_SIZE, &hdr[4]); 102 103 /* Set the initial stack pointer to the end of the bss. 104 The program's crt0 code must relocate it to a real stack. */ 105 H_PUT_16 (abfd, high_vma, &hdr[16]); 106 107 if (bfd_seek (abfd, (file_ptr) 0, SEEK_SET) != 0 108 || bfd_bwrite (hdr, (bfd_size_type) sizeof(hdr), abfd) != sizeof(hdr)) 109 return FALSE; 110 111 return TRUE; 112} 113 114static bfd_boolean 115msdos_set_section_contents (abfd, section, location, offset, count) 116 bfd *abfd; 117 sec_ptr section; 118 const PTR location; 119 file_ptr offset; 120 bfd_size_type count; 121{ 122 123 if (count == 0) 124 return TRUE; 125 126 section->filepos = EXE_PAGE_SIZE + bfd_get_section_vma (abfd, section); 127 128 if (bfd_get_section_flags (abfd, section) & SEC_LOAD) 129 { 130 if (bfd_seek (abfd, section->filepos + offset, SEEK_SET) != 0 131 || bfd_bwrite (location, count, abfd) != count) 132 return FALSE; 133 } 134 135 return TRUE; 136} 137 138 139 140#define msdos_mkobject aout_32_mkobject 141#define msdos_make_empty_symbol aout_32_make_empty_symbol 142#define msdos_bfd_reloc_type_lookup aout_32_reloc_type_lookup 143 144#define msdos_close_and_cleanup _bfd_generic_close_and_cleanup 145#define msdos_bfd_free_cached_info _bfd_generic_bfd_free_cached_info 146#define msdos_new_section_hook _bfd_generic_new_section_hook 147#define msdos_get_section_contents _bfd_generic_get_section_contents 148#define msdos_get_section_contents_in_window \ 149 _bfd_generic_get_section_contents_in_window 150#define msdos_bfd_get_relocated_section_contents \ 151 bfd_generic_get_relocated_section_contents 152#define msdos_bfd_relax_section bfd_generic_relax_section 153#define msdos_bfd_gc_sections bfd_generic_gc_sections 154#define msdos_bfd_merge_sections bfd_generic_merge_sections 155#define msdos_bfd_is_group_section bfd_generic_is_group_section 156#define msdos_bfd_discard_group bfd_generic_discard_group 157#define msdos_section_already_linked \ 158 _bfd_generic_section_already_linked 159#define msdos_bfd_link_hash_table_create _bfd_generic_link_hash_table_create 160#define msdos_bfd_link_hash_table_free _bfd_generic_link_hash_table_free 161#define msdos_bfd_link_add_symbols _bfd_generic_link_add_symbols 162#define msdos_bfd_link_just_syms _bfd_generic_link_just_syms 163#define msdos_bfd_final_link _bfd_generic_final_link 164#define msdos_bfd_link_split_section _bfd_generic_link_split_section 165#define msdos_set_arch_mach _bfd_generic_set_arch_mach 166 167#define msdos_get_symtab_upper_bound _bfd_nosymbols_get_symtab_upper_bound 168#define msdos_canonicalize_symtab _bfd_nosymbols_canonicalize_symtab 169#define msdos_print_symbol _bfd_nosymbols_print_symbol 170#define msdos_get_symbol_info _bfd_nosymbols_get_symbol_info 171#define msdos_find_nearest_line _bfd_nosymbols_find_nearest_line 172#define msdos_find_inliner_info _bfd_nosymbols_find_inliner_info 173#define msdos_get_lineno _bfd_nosymbols_get_lineno 174#define msdos_bfd_is_target_special_symbol ((bfd_boolean (*) (bfd *, asymbol *)) bfd_false) 175#define msdos_bfd_is_local_label_name _bfd_nosymbols_bfd_is_local_label_name 176#define msdos_bfd_make_debug_symbol _bfd_nosymbols_bfd_make_debug_symbol 177#define msdos_read_minisymbols _bfd_nosymbols_read_minisymbols 178#define msdos_minisymbol_to_symbol _bfd_nosymbols_minisymbol_to_symbol 179 180#define msdos_canonicalize_reloc _bfd_norelocs_canonicalize_reloc 181#define msdos_get_reloc_upper_bound _bfd_norelocs_get_reloc_upper_bound 182#define msdos_32_bfd_link_split_section _bfd_generic_link_split_section 183 184const bfd_target i386msdos_vec = 185 { 186 "msdos", /* name */ 187 bfd_target_msdos_flavour, 188 BFD_ENDIAN_LITTLE, /* target byte order */ 189 BFD_ENDIAN_LITTLE, /* target headers byte order */ 190 (EXEC_P), /* object flags */ 191 (SEC_CODE | SEC_DATA | SEC_HAS_CONTENTS 192 | SEC_ALLOC | SEC_LOAD), /* section flags */ 193 0, /* leading underscore */ 194 ' ', /* ar_pad_char */ 195 16, /* ar_max_namelen */ 196 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 197 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 198 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */ 199 bfd_getl64, bfd_getl_signed_64, bfd_putl64, 200 bfd_getl32, bfd_getl_signed_32, bfd_putl32, 201 bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */ 202 203 { 204 _bfd_dummy_target, 205 _bfd_dummy_target, /* bfd_check_format */ 206 _bfd_dummy_target, 207 _bfd_dummy_target, 208 }, 209 { 210 bfd_false, 211 msdos_mkobject, 212 _bfd_generic_mkarchive, 213 bfd_false, 214 }, 215 { /* bfd_write_contents */ 216 bfd_false, 217 msdos_write_object_contents, 218 _bfd_write_archive_contents, 219 bfd_false, 220 }, 221 222 BFD_JUMP_TABLE_GENERIC (msdos), 223 BFD_JUMP_TABLE_COPY (_bfd_generic), 224 BFD_JUMP_TABLE_CORE (_bfd_nocore), 225 BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive), 226 BFD_JUMP_TABLE_SYMBOLS (msdos), 227 BFD_JUMP_TABLE_RELOCS (msdos), 228 BFD_JUMP_TABLE_WRITE (msdos), 229 BFD_JUMP_TABLE_LINK (msdos), 230 BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic), 231 232 NULL, 233 234 (PTR) 0 235 }; 236 237 238