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, 2007
   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 3 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,
  22    MA 02110-1301, USA.  */
  23
  24 #include "sysdep.h"
  25 #include "bfd.h"
  26 #include "libbfd.h"
  27 #include "libaout.h"           /* BFD a.out internal data structures */
  28
  29 #include <sys/param.h>
  30 #ifdef HAVE_DIRENT_H
  31 # include <dirent.h>
  32 #else
  33 # ifdef HAVE_SYS_NDIR_H
  34 #  include <sys/ndir.h>
  35 # endif
  36 # ifdef HAVE_SYS_DIR_H
  37 #  include <sys/dir.h>
  38 # endif
  39 # ifdef HAVE_NDIR_H
  40 #  include <ndir.h>
  41 # endif
  42 #endif
  43 #include <signal.h>
  44
  45 #include <sys/user.h>           /* After a.out.h  */
  46
  47 #ifdef TRAD_HEADER
  48 #include TRAD_HEADER
  49 #endif
  50
  51 #ifndef NBPG
  52 # define NBPG getpagesize()
  53 #endif
  54
  55 struct trad_core_struct
  56 {
  57   asection *data_section;
  58   asection *stack_section;
  59   asection *reg_section;
  60   struct user u;
  61 };
  62
  63 #define core_upage(bfd) (&((bfd)->tdata.trad_core_data->u))
  64 #define core_datasec(bfd) ((bfd)->tdata.trad_core_data->data_section)
  65 #define core_stacksec(bfd) ((bfd)->tdata.trad_core_data->stack_section)
  66 #define core_regsec(bfd) ((bfd)->tdata.trad_core_data->reg_section)
  67
  68 /* forward declarations */
  69
  70 const bfd_target *trad_unix_core_file_p PARAMS ((bfd *abfd));
  71 char * trad_unix_core_file_failing_command PARAMS ((bfd *abfd));
  72 int trad_unix_core_file_failing_signal PARAMS ((bfd *abfd));
  73 #define trad_unix_core_file_matches_executable_p generic_core_file_matches_executable_p
  74 static void swap_abort PARAMS ((void));
  75
  76 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  77
  78 const bfd_target *
  79 trad_unix_core_file_p (abfd)
  80      bfd *abfd;
  81
  82 {
  83   int val;
  84   struct user u;
  85   struct trad_core_struct *rawptr;
  86   bfd_size_type amt;
  87   flagword flags;
  88
  89 #ifdef TRAD_CORE_USER_OFFSET
  90   /* If defined, this macro is the file position of the user struct.  */
  91   if (bfd_seek (abfd, (file_ptr) TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  92     return 0;
  93 #endif
  94
  95   val = bfd_bread ((void *) &u, (bfd_size_type) sizeof u, abfd);
  96   if (val != sizeof u)
  97     {
  98       /* Too small to be a core file */
  99       bfd_set_error (bfd_error_wrong_format);
 100       return 0;
 101     }
 102
 103   /* Sanity check perhaps??? */
 104   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages...  */
 105     {
 106       bfd_set_error (bfd_error_wrong_format);
 107       return 0;
 108     }
 109   if (u.u_ssize > 0x1000000)
 110     {
 111       bfd_set_error (bfd_error_wrong_format);
 112       return 0;
 113     }
 114
 115   /* Check that the size claimed is no greater than the file size.  */
 116   {
 117     struct stat statbuf;
 118
 119     if (bfd_stat (abfd, &statbuf) < 0)
 120       return 0;
 121
 122     if ((ufile_ptr) NBPG * (UPAGES + u.u_dsize
 123 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 124                             - u.u_tsize
 125 #endif
 126                             + u.u_ssize)
 127         > (ufile_ptr) statbuf.st_size)
 128       {
 129         bfd_set_error (bfd_error_wrong_format);
 130         return 0;
 131       }
 132 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 133     if (((ufile_ptr) NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 134 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 135         /* Some systems write the file too big.  */
 136          + TRAD_CORE_EXTRA_SIZE_ALLOWED
 137 #endif
 138          )
 139         < (ufile_ptr) statbuf.st_size)
 140       {
 141         /* The file is too big.  Maybe it's not a core file
 142            or we otherwise have bad values for u_dsize and u_ssize).  */
 143         bfd_set_error (bfd_error_wrong_format);
 144         return 0;
 145       }
 146 #endif
 147   }
 148
 149   /* OK, we believe you.  You're a core file (sure, sure).  */
 150
 151   /* Allocate both the upage and the struct core_data at once, so
 152      a single free() will free them both.  */
 153   amt = sizeof (struct trad_core_struct);
 154   rawptr = (struct trad_core_struct *) bfd_zmalloc (amt);
 155   if (rawptr == NULL)
 156     return 0;
 157
 158   abfd->tdata.trad_core_data = rawptr;
 159
 160   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 161
 162   /* Create the sections.  */
 163
 164   flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 165   core_stacksec(abfd) = bfd_make_section_anyway_with_flags (abfd, ".stack",
 166                                                             flags);
 167   if (core_stacksec (abfd) == NULL)
 168     goto fail;
 169   core_datasec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".data",
 170                                                             flags);
 171   if (core_datasec (abfd) == NULL)
 172     goto fail;
 173   core_regsec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".reg",
 174                                                            SEC_HAS_CONTENTS);
 175   if (core_regsec (abfd) == NULL)
 176     goto fail;
 177
 178   core_datasec (abfd)->size =  NBPG * u.u_dsize
 179 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 180     - NBPG * u.u_tsize
 181 #endif
 182       ;
 183   core_stacksec (abfd)->size = NBPG * u.u_ssize;
 184   core_regsec (abfd)->size = NBPG * UPAGES; /* Larger than sizeof struct u */
 185
 186   /* What a hack... we'd like to steal it from the exec file,
 187      since the upage does not seem to provide it.  FIXME.  */
 188 #ifdef HOST_DATA_START_ADDR
 189   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 190 #else
 191   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 192 #endif
 193
 194 #ifdef HOST_STACK_START_ADDR
 195   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 196 #else
 197   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 198 #endif
 199
 200   /* This is tricky.  As the "register section", we give them the entire
 201      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 202      There are two tricks with this, though.  One is that the rest of the
 203      registers might be at positive or negative (or both) displacements
 204      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 205      in kernel memory, and on other systems it is an offset from the beginning
 206      of the `struct user'.
 207
 208      As a practical matter, we don't know where the registers actually are,
 209      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 210      by setting the .regs section up so that its virtual memory address
 211      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 212      of the section to -u_ar0).  GDB uses this info to locate the regs,
 213      using minor trickery to get around the offset-or-absolute-addr problem.  */
 214   core_regsec (abfd)->vma = - (bfd_vma) (unsigned long) u.u_ar0;
 215
 216   core_datasec (abfd)->filepos = NBPG * UPAGES;
 217   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 218 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 219     - NBPG * u.u_tsize
 220 #endif
 221       ;
 222   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 223
 224   /* Align to word at least */
 225   core_stacksec (abfd)->alignment_power = 2;
 226   core_datasec (abfd)->alignment_power = 2;
 227   core_regsec (abfd)->alignment_power = 2;
 228
 229   return abfd->xvec;
 230
 231  fail:
 232   bfd_release (abfd, abfd->tdata.any);
 233   abfd->tdata.any = NULL;
 234   bfd_section_list_clear (abfd);
 235   return NULL;
 236 }
 237
 238 char *
 239 trad_unix_core_file_failing_command (abfd)
 240      bfd *abfd;
 241 {
 242 #ifndef NO_CORE_COMMAND
 243   char *com = abfd->tdata.trad_core_data->u.u_comm;
 244   if (*com)
 245     return com;
 246   else
 247 #endif
 248     return 0;
 249 }
 250
 251 int
 252 trad_unix_core_file_failing_signal (ignore_abfd)
 253      bfd *ignore_abfd ATTRIBUTE_UNUSED;
 254 {
 255 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 256   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 257 #else
 258   return -1;            /* FIXME, where is it? */
 259 #endif
 260 }
 261 \f
 262 /* If somebody calls any byte-swapping routines, shoot them.  */
 263 static void
 264 swap_abort ()
 265 {
 266   abort (); /* This way doesn't require any declaration for ANSI to fuck up */
 267 }
 268
 269 #define NO_GET ((bfd_vma (*) (const void *)) swap_abort)
 270 #define NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
 271 #define NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
 272 #define NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
 273 #define NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
 274 #define NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
 275
 276 const bfd_target trad_core_vec =
 277   {
 278     "trad-core",
 279     bfd_target_unknown_flavour,
 280     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 281     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 282     (HAS_RELOC | EXEC_P |       /* object flags */
 283      HAS_LINENO | HAS_DEBUG |
 284      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 285     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 286     0,                                                     /* symbol prefix */
 287     ' ',                                                   /* ar_pad_char */
 288     16,                                                    /* ar_max_namelen */
 289     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit data */
 290     NO_GET, NO_GETS, NO_PUT,            /* 32 bit data */
 291     NO_GET, NO_GETS, NO_PUT,            /* 16 bit data */
 292     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit hdrs */
 293     NO_GET, NO_GETS, NO_PUT,            /* 32 bit hdrs */
 294     NO_GET, NO_GETS, NO_PUT,            /* 16 bit hdrs */
 295
 296     {                           /* bfd_check_format */
 297       _bfd_dummy_target,                /* unknown format */
 298       _bfd_dummy_target,                /* object file */
 299       _bfd_dummy_target,                /* archive */
 300       trad_unix_core_file_p             /* a core file */
 301     },
 302     {                           /* bfd_set_format */
 303       bfd_false, bfd_false,
 304       bfd_false, bfd_false
 305     },
 306     {                           /* bfd_write_contents */
 307       bfd_false, bfd_false,
 308       bfd_false, bfd_false
 309     },
 310
 311     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 312     BFD_JUMP_TABLE_COPY (_bfd_generic),
 313     BFD_JUMP_TABLE_CORE (trad_unix),
 314     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 315     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 316     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 317     BFD_JUMP_TABLE_WRITE (_bfd_generic),
 318     BFD_JUMP_TABLE_LINK (_bfd_nolink),
 319     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 320
 321     NULL,
 322
 323     (PTR) 0                     /* backend_data */
 324   };