bfd/trad-core.c

   1 /* BFD back end for traditional Unix core files (U-area and raw sections)
   2    Copyright 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
   3    2000, 2001, 2002, 2003, 2004, 2005, 2006
   4    Free Software Foundation, Inc.
   5    Written by John Gilmore of Cygnus Support.
   6
   7 This file is part of BFD, the Binary File Descriptor library.
   8
   9 This program is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2 of the License, or
  12 (at your option) any later version.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  22
  23 #include "bfd.h"
  24 #include "sysdep.h"
  25 #include "libbfd.h"
  26 #include "libaout.h"           /* BFD a.out internal data structures */
  27
  28 #include <sys/param.h>
  29 #ifdef HAVE_DIRENT_H
  30 # include <dirent.h>
  31 #else
  32 # ifdef HAVE_SYS_NDIR_H
  33 #  include <sys/ndir.h>
  34 # endif
  35 # ifdef HAVE_SYS_DIR_H
  36 #  include <sys/dir.h>
  37 # endif
  38 # ifdef HAVE_NDIR_H
  39 #  include <ndir.h>
  40 # endif
  41 #endif
  42 #include <signal.h>
  43
  44 #include <sys/user.h>           /* After a.out.h  */
  45
  46 #ifdef TRAD_HEADER
  47 #include TRAD_HEADER
  48 #endif
  49
  50 struct trad_core_struct
  51 {
  52   asection *data_section;
  53   asection *stack_section;
  54   asection *reg_section;
  55   struct user u;
  56 };
  57
  58 #define core_upage(bfd) (&((bfd)->tdata.trad_core_data->u))
  59 #define core_datasec(bfd) ((bfd)->tdata.trad_core_data->data_section)
  60 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
  61 #define core_regsec(bfd) ((bfd)->tdata.trad_core_data->reg_section)
  62
  63 /* forward declarations */
  64
  65 const bfd_target *trad_unix_core_file_p PARAMS ((bfd *abfd));
  66 char * trad_unix_core_file_failing_command PARAMS ((bfd *abfd));
  67 int trad_unix_core_file_failing_signal PARAMS ((bfd *abfd));
  68 #define trad_unix_core_file_matches_executable_p generic_core_file_matches_executable_p
  69 static void swap_abort PARAMS ((void));
  70
  71 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  72
  73 const bfd_target *
  74 trad_unix_core_file_p (abfd)
  75      bfd *abfd;
  76
  77 {
  78   int val;
  79   struct user u;
  80   struct trad_core_struct *rawptr;
  81   bfd_size_type amt;
  82   flagword flags;
  83
  84 #ifdef TRAD_CORE_USER_OFFSET
  85   /* If defined, this macro is the file position of the user struct.  */
  86   if (bfd_seek (abfd, (file_ptr) TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  87     return 0;
  88 #endif
  89
  90   val = bfd_bread ((void *) &u, (bfd_size_type) sizeof u, abfd);
  91   if (val != sizeof u)
  92     {
  93       /* Too small to be a core file */
  94       bfd_set_error (bfd_error_wrong_format);
  95       return 0;
  96     }
  97
  98   /* Sanity check perhaps??? */
  99   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages...  */
 100     {
 101       bfd_set_error (bfd_error_wrong_format);
 102       return 0;
 103     }
 104   if (u.u_ssize > 0x1000000)
 105     {
 106       bfd_set_error (bfd_error_wrong_format);
 107       return 0;
 108     }
 109
 110   /* Check that the size claimed is no greater than the file size.  */
 111   {
 112     struct stat statbuf;
 113
 114     if (bfd_stat (abfd, &statbuf) < 0)
 115       return 0;
 116
 117     if ((unsigned long) (NBPG * (UPAGES + u.u_dsize
 118 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 119                                  - u.u_tsize
 120 #endif
 121                                  + u.u_ssize))
 122         > (unsigned long) statbuf.st_size)
 123       {
 124         bfd_set_error (bfd_error_wrong_format);
 125         return 0;
 126       }
 127 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 128     if ((unsigned long) (NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 129 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 130         /* Some systems write the file too big.  */
 131                          + TRAD_CORE_EXTRA_SIZE_ALLOWED
 132 #endif
 133                          )
 134         < (unsigned long) statbuf.st_size)
 135       {
 136         /* The file is too big.  Maybe it's not a core file
 137            or we otherwise have bad values for u_dsize and u_ssize).  */
 138         bfd_set_error (bfd_error_wrong_format);
 139         return 0;
 140       }
 141 #endif
 142   }
 143
 144   /* OK, we believe you.  You're a core file (sure, sure).  */
 145
 146   /* Allocate both the upage and the struct core_data at once, so
 147      a single free() will free them both.  */
 148   amt = sizeof (struct trad_core_struct);
 149   rawptr = (struct trad_core_struct *) bfd_zmalloc (amt);
 150   if (rawptr == NULL)
 151     return 0;
 152
 153   abfd->tdata.trad_core_data = rawptr;
 154
 155   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 156
 157   /* Create the sections.  */
 158
 159   flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 160   core_stacksec(abfd) = bfd_make_section_anyway_with_flags (abfd, ".stack",
 161                                                             flags);
 162   if (core_stacksec (abfd) == NULL)
 163     goto fail;
 164   core_datasec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".data",
 165                                                             flags);
 166   if (core_datasec (abfd) == NULL)
 167     goto fail;
 168   core_regsec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".reg",
 169                                                            SEC_HAS_CONTENTS);
 170   if (core_regsec (abfd) == NULL)
 171     goto fail;
 172
 173   core_datasec (abfd)->size =  NBPG * u.u_dsize
 174 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 175     - NBPG * u.u_tsize
 176 #endif
 177       ;
 178   core_stacksec (abfd)->size = NBPG * u.u_ssize;
 179   core_regsec (abfd)->size = NBPG * UPAGES; /* Larger than sizeof struct u */
 180
 181   /* What a hack... we'd like to steal it from the exec file,
 182      since the upage does not seem to provide it.  FIXME.  */
 183 #ifdef HOST_DATA_START_ADDR
 184   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 185 #else
 186   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 187 #endif
 188
 189 #ifdef HOST_STACK_START_ADDR
 190   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 191 #else
 192   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 193 #endif
 194
 195   /* This is tricky.  As the "register section", we give them the entire
 196      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 197      There are two tricks with this, though.  One is that the rest of the
 198      registers might be at positive or negative (or both) displacements
 199      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 200      in kernel memory, and on other systems it is an offset from the beginning
 201      of the `struct user'.
 202
 203      As a practical matter, we don't know where the registers actually are,
 204      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 205      by setting the .regs section up so that its virtual memory address
 206      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 207      of the section to -u_ar0).  GDB uses this info to locate the regs,
 208      using minor trickery to get around the offset-or-absolute-addr problem.  */
 209   core_regsec (abfd)->vma = - (bfd_vma) (unsigned long) u.u_ar0;
 210
 211   core_datasec (abfd)->filepos = NBPG * UPAGES;
 212   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 213 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 214     - NBPG * u.u_tsize
 215 #endif
 216       ;
 217   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 218
 219   /* Align to word at least */
 220   core_stacksec (abfd)->alignment_power = 2;
 221   core_datasec (abfd)->alignment_power = 2;
 222   core_regsec (abfd)->alignment_power = 2;
 223
 224   return abfd->xvec;
 225
 226  fail:
 227   bfd_release (abfd, abfd->tdata.any);
 228   abfd->tdata.any = NULL;
 229   bfd_section_list_clear (abfd);
 230   return NULL;
 231 }
 232
 233 char *
 234 trad_unix_core_file_failing_command (abfd)
 235      bfd *abfd;
 236 {
 237 #ifndef NO_CORE_COMMAND
 238   char *com = abfd->tdata.trad_core_data->u.u_comm;
 239   if (*com)
 240     return com;
 241   else
 242 #endif
 243     return 0;
 244 }
 245
 246 int
 247 trad_unix_core_file_failing_signal (ignore_abfd)
 248      bfd *ignore_abfd ATTRIBUTE_UNUSED;
 249 {
 250 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 251   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 252 #else
 253   return -1;            /* FIXME, where is it? */
 254 #endif
 255 }
 256 \f
 257 /* If somebody calls any byte-swapping routines, shoot them.  */
 258 static void
 259 swap_abort ()
 260 {
 261   abort (); /* This way doesn't require any declaration for ANSI to fuck up */
 262 }
 263
 264 #define NO_GET ((bfd_vma (*) (const void *)) swap_abort)
 265 #define NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
 266 #define NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
 267 #define NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
 268 #define NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
 269 #define NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
 270
 271 const bfd_target trad_core_vec =
 272   {
 273     "trad-core",
 274     bfd_target_unknown_flavour,
 275     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 276     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 277     (HAS_RELOC | EXEC_P |       /* object flags */
 278      HAS_LINENO | HAS_DEBUG |
 279      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 280     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 281     0,                                                     /* symbol prefix */
 282     ' ',                                                   /* ar_pad_char */
 283     16,                                                    /* ar_max_namelen */
 284     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit data */
 285     NO_GET, NO_GETS, NO_PUT,            /* 32 bit data */
 286     NO_GET, NO_GETS, NO_PUT,            /* 16 bit data */
 287     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit hdrs */
 288     NO_GET, NO_GETS, NO_PUT,            /* 32 bit hdrs */
 289     NO_GET, NO_GETS, NO_PUT,            /* 16 bit hdrs */
 290
 291     {                           /* bfd_check_format */
 292       _bfd_dummy_target,                /* unknown format */
 293       _bfd_dummy_target,                /* object file */
 294       _bfd_dummy_target,                /* archive */
 295       trad_unix_core_file_p             /* a core file */
 296     },
 297     {                           /* bfd_set_format */
 298       bfd_false, bfd_false,
 299       bfd_false, bfd_false
 300     },
 301     {                           /* bfd_write_contents */
 302       bfd_false, bfd_false,
 303       bfd_false, bfd_false
 304     },
 305
 306     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 307     BFD_JUMP_TABLE_COPY (_bfd_generic),
 308     BFD_JUMP_TABLE_CORE (trad_unix),
 309     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 310     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 311     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 312     BFD_JUMP_TABLE_WRITE (_bfd_generic),
 313     BFD_JUMP_TABLE_LINK (_bfd_nolink),
 314     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 315
 316     NULL,
 317
 318     (PTR) 0                     /* backend_data */
 319   };