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, 98, 99, 2000
   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 #ifdef HAVE_DIRENT_H
  29 # include <dirent.h>
  30 #else
  31 # ifdef HAVE_SYS_NDIR_H
  32 #  include <sys/ndir.h>
  33 # endif
  34 # ifdef HAVE_SYS_DIR_H
  35 #  include <sys/dir.h>
  36 # endif
  37 # ifdef HAVE_NDIR_H
  38 #  include <ndir.h>
  39 # endif
  40 #endif
  41 #include <signal.h>
  42
  43 #include <sys/user.h>           /* After a.out.h  */
  44
  45 #ifdef TRAD_HEADER
  46 #include TRAD_HEADER
  47 #endif
  48
  49   struct trad_core_struct
  50     {
  51       asection *data_section;
  52       asection *stack_section;
  53       asection *reg_section;
  54       struct user u;
  55     };
  56
  57 #define core_upage(bfd) (&((bfd)->tdata.trad_core_data->u))
  58 #define core_datasec(bfd) ((bfd)->tdata.trad_core_data->data_section)
  59 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
  60 #define core_regsec(bfd) ((bfd)->tdata.trad_core_data->reg_section)
  61
  62 /* forward declarations */
  63
  64 const bfd_target *trad_unix_core_file_p PARAMS ((bfd *abfd));
  65 char *          trad_unix_core_file_failing_command PARAMS ((bfd *abfd));
  66 int             trad_unix_core_file_failing_signal PARAMS ((bfd *abfd));
  67 boolean         trad_unix_core_file_matches_executable_p
  68                          PARAMS ((bfd *core_bfd, bfd *exec_bfd));
  69 static void     swap_abort PARAMS ((void));
  70
  71 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  72
  73 /* ARGSUSED */
  74 const bfd_target *
  75 trad_unix_core_file_p (abfd)
  76      bfd *abfd;
  77
  78 {
  79   int val;
  80   struct user u;
  81   struct trad_core_struct *rawptr;
  82
  83 #ifdef TRAD_CORE_USER_OFFSET
  84   /* If defined, this macro is the file position of the user struct.  */
  85   if (bfd_seek (abfd, TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  86     return 0;
  87 #endif
  88
  89   val = bfd_read ((void *)&u, 1, sizeof u, abfd);
  90   if (val != sizeof u)
  91     {
  92       /* Too small to be a core file */
  93       bfd_set_error (bfd_error_wrong_format);
  94       return 0;
  95     }
  96
  97   /* Sanity check perhaps??? */
  98   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages... */
  99     {
 100       bfd_set_error (bfd_error_wrong_format);
 101       return 0;
 102     }
 103   if (u.u_ssize > 0x1000000)
 104     {
 105       bfd_set_error (bfd_error_wrong_format);
 106       return 0;
 107     }
 108
 109   /* Check that the size claimed is no greater than the file size.  */
 110   {
 111     FILE *stream = bfd_cache_lookup (abfd);
 112     struct stat statbuf;
 113     if (stream == NULL)
 114       return 0;
 115     if (fstat (fileno (stream), &statbuf) < 0)
 116       {
 117         bfd_set_error (bfd_error_system_call);
 118         return 0;
 119       }
 120     if ((unsigned long) (NBPG * (UPAGES + u.u_dsize
 121 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 122                                  - u.u_tsize
 123 #endif
 124                                  + u.u_ssize))
 125         > (unsigned long) statbuf.st_size)
 126       {
 127         bfd_set_error (bfd_error_wrong_format);
 128         return 0;
 129       }
 130 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 131     if ((unsigned long) (NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 132 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 133         /* Some systems write the file too big.  */
 134                          + TRAD_CORE_EXTRA_SIZE_ALLOWED
 135 #endif
 136                          )
 137         < (unsigned long) statbuf.st_size)
 138       {
 139         /* The file is too big.  Maybe it's not a core file
 140            or we otherwise have bad values for u_dsize and u_ssize).  */
 141         bfd_set_error (bfd_error_wrong_format);
 142         return 0;
 143       }
 144 #endif
 145   }
 146
 147   /* OK, we believe you.  You're a core file (sure, sure).  */
 148
 149   /* Allocate both the upage and the struct core_data at once, so
 150      a single free() will free them both.  */
 151   rawptr = (struct trad_core_struct *)
 152                 bfd_zmalloc (sizeof (struct trad_core_struct));
 153   if (rawptr == NULL)
 154     return 0;
 155
 156   abfd->tdata.trad_core_data = rawptr;
 157
 158   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 159
 160   /* Create the sections.  This is raunchy, but bfd_close wants to free
 161      them separately.  */
 162
 163   core_stacksec(abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 164   if (core_stacksec (abfd) == NULL)
 165     return NULL;
 166   core_datasec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 167   if (core_datasec (abfd) == NULL)
 168     return NULL;
 169   core_regsec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
 170   if (core_regsec (abfd) == NULL)
 171     return NULL;
 172
 173   core_stacksec (abfd)->name = ".stack";
 174   core_datasec (abfd)->name = ".data";
 175   core_regsec (abfd)->name = ".reg";
 176
 177   core_stacksec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 178   core_datasec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 179   core_regsec (abfd)->flags = SEC_HAS_CONTENTS;
 180
 181   core_datasec (abfd)->_raw_size =  NBPG * u.u_dsize
 182 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 183     - NBPG * u.u_tsize
 184 #endif
 185       ;
 186   core_stacksec (abfd)->_raw_size = NBPG * u.u_ssize;
 187   core_regsec (abfd)->_raw_size = NBPG * UPAGES; /* Larger than sizeof struct u */
 188
 189   /* What a hack... we'd like to steal it from the exec file,
 190      since the upage does not seem to provide it.  FIXME.  */
 191 #ifdef HOST_DATA_START_ADDR
 192   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 193 #else
 194   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 195 #endif
 196
 197 #ifdef HOST_STACK_START_ADDR
 198   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 199 #else
 200   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 201 #endif
 202
 203   /* This is tricky.  As the "register section", we give them the entire
 204      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 205      There are two tricks with this, though.  One is that the rest of the
 206      registers might be at positive or negative (or both) displacements
 207      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 208      in kernel memory, and on other systems it is an offset from the beginning
 209      of the `struct user'.
 210
 211      As a practical matter, we don't know where the registers actually are,
 212      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 213      by setting the .regs section up so that its virtual memory address
 214      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 215      of the section to -u_ar0).  GDB uses this info to locate the regs,
 216      using minor trickery to get around the offset-or-absolute-addr problem. */
 217   core_regsec (abfd)->vma = - (bfd_vma) u.u_ar0;
 218
 219   core_datasec (abfd)->filepos = NBPG * UPAGES;
 220   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 221 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 222     - NBPG * u.u_tsize
 223 #endif
 224       ;
 225   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 226
 227   /* Align to word at least */
 228   core_stacksec (abfd)->alignment_power = 2;
 229   core_datasec (abfd)->alignment_power = 2;
 230   core_regsec (abfd)->alignment_power = 2;
 231
 232   abfd->sections = core_stacksec (abfd);
 233   core_stacksec (abfd)->next = core_datasec (abfd);
 234   core_datasec (abfd)->next = core_regsec (abfd);
 235   abfd->section_count = 3;
 236
 237   return abfd->xvec;
 238 }
 239
 240 char *
 241 trad_unix_core_file_failing_command (abfd)
 242      bfd *abfd;
 243 {
 244 #ifndef NO_CORE_COMMAND
 245   char *com = abfd->tdata.trad_core_data->u.u_comm;
 246   if (*com)
 247     return com;
 248   else
 249 #endif
 250     return 0;
 251 }
 252
 253 /* ARGSUSED */
 254 int
 255 trad_unix_core_file_failing_signal (ignore_abfd)
 256      bfd *ignore_abfd ATTRIBUTE_UNUSED;
 257 {
 258 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 259   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 260 #else
 261   return -1;            /* FIXME, where is it? */
 262 #endif
 263 }
 264
 265 /* ARGSUSED */
 266 boolean
 267 trad_unix_core_file_matches_executable_p  (core_bfd, exec_bfd)
 268      bfd *core_bfd ATTRIBUTE_UNUSED;
 269      bfd *exec_bfd ATTRIBUTE_UNUSED;
 270 {
 271   return true;          /* FIXME, We have no way of telling at this point */
 272 }
 273 \f
 274 /* If somebody calls any byte-swapping routines, shoot them.  */
 275 static void
 276 swap_abort()
 277 {
 278   abort(); /* This way doesn't require any declaration for ANSI to fuck up */
 279 }
 280 #define NO_GET  ((bfd_vma (*) PARAMS ((   const bfd_byte *))) swap_abort )
 281 #define NO_PUT  ((void    (*) PARAMS ((bfd_vma, bfd_byte *))) swap_abort )
 282 #define NO_SIGNED_GET \
 283   ((bfd_signed_vma (*) PARAMS ((const bfd_byte *))) swap_abort )
 284
 285 const bfd_target trad_core_vec =
 286   {
 287     "trad-core",
 288     bfd_target_unknown_flavour,
 289     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 290     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 291     (HAS_RELOC | EXEC_P |       /* object flags */
 292      HAS_LINENO | HAS_DEBUG |
 293      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 294     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 295     0,                                                     /* symbol prefix */
 296     ' ',                                                   /* ar_pad_char */
 297     16,                                                    /* ar_max_namelen */
 298     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 64 bit data */
 299     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 32 bit data */
 300     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 16 bit data */
 301     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 64 bit hdrs */
 302     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 32 bit hdrs */
 303     NO_GET, NO_SIGNED_GET, NO_PUT,      /* 16 bit hdrs */
 304
 305     {                           /* bfd_check_format */
 306      _bfd_dummy_target,         /* unknown format */
 307      _bfd_dummy_target,         /* object file */
 308      _bfd_dummy_target,         /* archive */
 309      trad_unix_core_file_p      /* a core file */
 310     },
 311     {                           /* bfd_set_format */
 312      bfd_false, bfd_false,
 313      bfd_false, bfd_false
 314     },
 315     {                           /* bfd_write_contents */
 316      bfd_false, bfd_false,
 317      bfd_false, bfd_false
 318     },
 319
 320        BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 321        BFD_JUMP_TABLE_COPY (_bfd_generic),
 322        BFD_JUMP_TABLE_CORE (trad_unix),
 323        BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 324        BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 325        BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 326        BFD_JUMP_TABLE_WRITE (_bfd_generic),
 327        BFD_JUMP_TABLE_LINK (_bfd_nolink),
 328        BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 329
 330     NULL,
 331
 332     (PTR) 0                     /* backend_data */
 333 };