bfd/trad-core.c

   1 /* BFD back end for traditional Unix core files (U-area and raw sections)
   2    Copyright 1988, 89, 91, 92, 93, 94, 95, 96, 1998
   3    Free Software Foundation, Inc.
   4    Written by John Gilmore of Cygnus Support.
   5
   6 This file is part of BFD, the Binary File Descriptor library.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  21
  22 #include "bfd.h"
  23 #include "sysdep.h"
  24 #include "libbfd.h"
  25 #include "libaout.h"           /* BFD a.out internal data structures */
  26
  27 #include <sys/param.h>
  28 #include <sys/dir.h>
  29 #include <signal.h>
  30
  31 #include <sys/user.h>           /* After a.out.h  */
  32
  33 #ifdef TRAD_HEADER
  34 #include TRAD_HEADER
  35 #endif
  36
  37   struct trad_core_struct
  38     {
  39       asection *data_section;
  40       asection *stack_section;
  41       asection *reg_section;
  42       struct user u;
  43     };
  44
  45 #define core_upage(bfd) (&((bfd)->tdata.trad_core_data->u))
  46 #define core_datasec(bfd) ((bfd)->tdata.trad_core_data->data_section)
  47 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
  48 #define core_regsec(bfd) ((bfd)->tdata.trad_core_data->reg_section)
  49
  50 /* forward declarations */
  51
  52 const bfd_target *trad_unix_core_file_p PARAMS ((bfd *abfd));
  53 char *          trad_unix_core_file_failing_command PARAMS ((bfd *abfd));
  54 int             trad_unix_core_file_failing_signal PARAMS ((bfd *abfd));
  55 boolean         trad_unix_core_file_matches_executable_p
  56                          PARAMS ((bfd *core_bfd, bfd *exec_bfd));
  57 static void     swap_abort PARAMS ((void));
  58
  59 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  60
  61 /* ARGSUSED */
  62 const bfd_target *
  63 trad_unix_core_file_p (abfd)
  64      bfd *abfd;
  65
  66 {
  67   int val;
  68   struct user u;
  69   struct trad_core_struct *rawptr;
  70
  71 #ifdef TRAD_CORE_USER_OFFSET
  72   /* If defined, this macro is the file position of the user struct.  */
  73   if (bfd_seek (abfd, TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  74     return 0;
  75 #endif
  76
  77   val = bfd_read ((void *)&u, 1, sizeof u, abfd);
  78   if (val != sizeof u)
  79     {
  80       /* Too small to be a core file */
  81       bfd_set_error (bfd_error_wrong_format);
  82       return 0;
  83     }
  84
  85   /* Sanity check perhaps??? */
  86   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages... */
  87     {
  88       bfd_set_error (bfd_error_wrong_format);
  89       return 0;
  90     }
  91   if (u.u_ssize > 0x1000000)
  92     {
  93       bfd_set_error (bfd_error_wrong_format);
  94       return 0;
  95     }
  96
  97   /* Check that the size claimed is no greater than the file size.  */
  98   {
  99     FILE *stream = bfd_cache_lookup (abfd);
 100     struct stat statbuf;
 101     if (stream == NULL)
 102       return 0;
 103     if (fstat (fileno (stream), &statbuf) < 0)
 104       {
 105         bfd_set_error (bfd_error_system_call);
 106         return 0;
 107       }
 108     if (NBPG * (UPAGES + u.u_dsize
 109 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 110                 - u.u_tsize
 111 #endif
 112                 + u.u_ssize) > statbuf.st_size)
 113       {
 114         bfd_set_error (bfd_error_file_truncated);
 115         return 0;
 116       }
 117 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 118     if (NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 119 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 120         /* Some systems write the file too big.  */
 121         + TRAD_CORE_EXTRA_SIZE_ALLOWED
 122 #endif
 123         < statbuf.st_size)
 124       {
 125         /* The file is too big.  Maybe it's not a core file
 126            or we otherwise have bad values for u_dsize and u_ssize).  */
 127         bfd_set_error (bfd_error_wrong_format);
 128         return 0;
 129       }
 130 #endif
 131   }
 132
 133   /* OK, we believe you.  You're a core file (sure, sure).  */
 134
 135   /* Allocate both the upage and the struct core_data at once, so
 136      a single free() will free them both.  */
 137   rawptr = (struct trad_core_struct *)
 138                 bfd_zmalloc (sizeof (struct trad_core_struct));
 139   if (rawptr == NULL)
 140     return 0;
 141
 142   abfd->tdata.trad_core_data = rawptr;
 143
 144   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 145
 146   /* Create the sections.  This is raunchy, but bfd_close wants to free
 147      them separately.  */
 148
 149   core_stacksec(abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 150   if (core_stacksec (abfd) == NULL)
 151     return NULL;
 152   core_datasec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 153   if (core_datasec (abfd) == NULL)
 154     return NULL;
 155   core_regsec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 156   if (core_regsec (abfd) == NULL)
 157     return NULL;
 158
 159   core_stacksec (abfd)->name = ".stack";
 160   core_datasec (abfd)->name = ".data";
 161   core_regsec (abfd)->name = ".reg";
 162
 163   core_stacksec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 164   core_datasec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 165   core_regsec (abfd)->flags = SEC_HAS_CONTENTS;
 166
 167   core_datasec (abfd)->_raw_size =  NBPG * u.u_dsize
 168 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 169     - NBPG * u.u_tsize
 170 #endif
 171       ;
 172   core_stacksec (abfd)->_raw_size = NBPG * u.u_ssize;
 173   core_regsec (abfd)->_raw_size = NBPG * UPAGES; /* Larger than sizeof struct u */
 174
 175   /* What a hack... we'd like to steal it from the exec file,
 176      since the upage does not seem to provide it.  FIXME.  */
 177 #ifdef HOST_DATA_START_ADDR
 178   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 179 #else
 180   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 181 #endif
 182
 183 #ifdef HOST_STACK_START_ADDR
 184   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 185 #else
 186   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 187 #endif
 188
 189   /* This is tricky.  As the "register section", we give them the entire
 190      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 191      There are two tricks with this, though.  One is that the rest of the
 192      registers might be at positive or negative (or both) displacements
 193      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 194      in kernel memory, and on other systems it is an offset from the beginning
 195      of the `struct user'.
 196
 197      As a practical matter, we don't know where the registers actually are,
 198      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 199      by setting the .regs section up so that its virtual memory address
 200      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 201      of the section to -u_ar0).  GDB uses this info to locate the regs,
 202      using minor trickery to get around the offset-or-absolute-addr problem. */
 203   core_regsec (abfd)->vma = 0 - (bfd_vma) u.u_ar0;
 204
 205   core_datasec (abfd)->filepos = NBPG * UPAGES;
 206   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 207 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 208     - NBPG * u.u_tsize
 209 #endif
 210       ;
 211   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 212
 213   /* Align to word at least */
 214   core_stacksec (abfd)->alignment_power = 2;
 215   core_datasec (abfd)->alignment_power = 2;
 216   core_regsec (abfd)->alignment_power = 2;
 217
 218   abfd->sections = core_stacksec (abfd);
 219   core_stacksec (abfd)->next = core_datasec (abfd);
 220   core_datasec (abfd)->next = core_regsec (abfd);
 221   abfd->section_count = 3;
 222
 223   return abfd->xvec;
 224 }
 225
 226 char *
 227 trad_unix_core_file_failing_command (abfd)
 228      bfd *abfd;
 229 {
 230 #ifndef NO_CORE_COMMAND
 231   char *com = abfd->tdata.trad_core_data->u.u_comm;
 232   if (*com)
 233     return com;
 234   else
 235 #endif
 236     return 0;
 237 }
 238
 239 /* ARGSUSED */
 240 int
 241 trad_unix_core_file_failing_signal (ignore_abfd)
 242      bfd *ignore_abfd;
 243 {
 244 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 245   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 246 #else
 247   return -1;            /* FIXME, where is it? */
 248 #endif
 249 }
 250
 251 /* ARGSUSED */
 252 boolean
 253 trad_unix_core_file_matches_executable_p  (core_bfd, exec_bfd)
 254      bfd *core_bfd, *exec_bfd;
 255 {
 256   return true;          /* FIXME, We have no way of telling at this point */
 257 }
 258 \f
 259 /* If somebody calls any byte-swapping routines, shoot them.  */
 260 static void
 261 swap_abort()
 262 {
 263   abort(); /* This way doesn't require any declaration for ANSI to fuck up */
 264 }
 265 #define NO_GET  ((bfd_vma (*) PARAMS ((   const bfd_byte *))) swap_abort )
 266 #define NO_PUT  ((void    (*) PARAMS ((bfd_vma, bfd_byte *))) swap_abort )
 267 #define NO_SIGNED_GET \
 268   ((bfd_signed_vma (*) PARAMS ((const bfd_byte *))) swap_abort )
 269
 270 const bfd_target trad_core_vec =
 271   {
 272     "trad-core",
 273     bfd_target_unknown_flavour,
 274     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 275     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 276     (HAS_RELOC | EXEC_P |       /* object flags */
 277      HAS_LINENO | HAS_DEBUG |
 278      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 279     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 280     0,                                                     /* symbol prefix */
 281     ' ',                                                   /* ar_pad_char */
 282     16,                                                    /* ar_max_namelen */
 283     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 64 bit data */
 284     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 32 bit data */
 285     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 16 bit data */
 286     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 64 bit hdrs */
 287     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 32 bit hdrs */
 288     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 16 bit hdrs */
 289
 290     {                           /* bfd_check_format */
 291      _bfd_dummy_target,         /* unknown format */
 292      _bfd_dummy_target,         /* object file */
 293      _bfd_dummy_target,         /* archive */
 294      trad_unix_core_file_p      /* a core file */
 295     },
 296     {                           /* bfd_set_format */
 297      bfd_false, bfd_false,
 298      bfd_false, bfd_false
 299     },
 300     {                           /* bfd_write_contents */
 301      bfd_false, bfd_false,
 302      bfd_false, bfd_false
 303     },
 304
 305        BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 306        BFD_JUMP_TABLE_COPY (_bfd_generic),
 307        BFD_JUMP_TABLE_CORE (trad_unix),
 308        BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 309        BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 310        BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 311        BFD_JUMP_TABLE_WRITE (_bfd_generic),
 312        BFD_JUMP_TABLE_LINK (_bfd_nolink),
 313        BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 314
 315     (PTR) 0                     /* backend_data */
 316 };