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, 2011
   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 #define trad_unix_core_file_pid _bfd_nocore_core_file_pid
  75 static void swap_abort PARAMS ((void));
  76
  77 /* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
  78
  79 const bfd_target *
  80 trad_unix_core_file_p (abfd)
  81      bfd *abfd;
  82
  83 {
  84   int val;
  85   struct user u;
  86   struct trad_core_struct *rawptr;
  87   bfd_size_type amt;
  88   flagword flags;
  89
  90 #ifdef TRAD_CORE_USER_OFFSET
  91   /* If defined, this macro is the file position of the user struct.  */
  92   if (bfd_seek (abfd, (file_ptr) TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
  93     return 0;
  94 #endif
  95
  96   val = bfd_bread ((void *) &u, (bfd_size_type) sizeof u, abfd);
  97   if (val != sizeof u)
  98     {
  99       /* Too small to be a core file */
 100       bfd_set_error (bfd_error_wrong_format);
 101       return 0;
 102     }
 103
 104   /* Sanity check perhaps??? */
 105   if (u.u_dsize > 0x1000000)    /* Remember, it's in pages...  */
 106     {
 107       bfd_set_error (bfd_error_wrong_format);
 108       return 0;
 109     }
 110   if (u.u_ssize > 0x1000000)
 111     {
 112       bfd_set_error (bfd_error_wrong_format);
 113       return 0;
 114     }
 115
 116   /* Check that the size claimed is no greater than the file size.  */
 117   {
 118     struct stat statbuf;
 119
 120     if (bfd_stat (abfd, &statbuf) < 0)
 121       return 0;
 122
 123     if ((ufile_ptr) NBPG * (UPAGES + u.u_dsize
 124 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 125                             - u.u_tsize
 126 #endif
 127                             + u.u_ssize)
 128         > (ufile_ptr) statbuf.st_size)
 129       {
 130         bfd_set_error (bfd_error_wrong_format);
 131         return 0;
 132       }
 133 #ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
 134     if (((ufile_ptr) NBPG * (UPAGES + u.u_dsize + u.u_ssize)
 135 #ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
 136         /* Some systems write the file too big.  */
 137          + TRAD_CORE_EXTRA_SIZE_ALLOWED
 138 #endif
 139          )
 140         < (ufile_ptr) statbuf.st_size)
 141       {
 142         /* The file is too big.  Maybe it's not a core file
 143            or we otherwise have bad values for u_dsize and u_ssize).  */
 144         bfd_set_error (bfd_error_wrong_format);
 145         return 0;
 146       }
 147 #endif
 148   }
 149
 150   /* OK, we believe you.  You're a core file (sure, sure).  */
 151
 152   /* Allocate both the upage and the struct core_data at once, so
 153      a single free() will free them both.  */
 154   amt = sizeof (struct trad_core_struct);
 155   rawptr = (struct trad_core_struct *) bfd_zmalloc (amt);
 156   if (rawptr == NULL)
 157     return 0;
 158
 159   abfd->tdata.trad_core_data = rawptr;
 160
 161   rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
 162
 163   /* Create the sections.  */
 164
 165   flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
 166   core_stacksec(abfd) = bfd_make_section_anyway_with_flags (abfd, ".stack",
 167                                                             flags);
 168   if (core_stacksec (abfd) == NULL)
 169     goto fail;
 170   core_datasec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".data",
 171                                                             flags);
 172   if (core_datasec (abfd) == NULL)
 173     goto fail;
 174   core_regsec (abfd) = bfd_make_section_anyway_with_flags (abfd, ".reg",
 175                                                            SEC_HAS_CONTENTS);
 176   if (core_regsec (abfd) == NULL)
 177     goto fail;
 178
 179   core_datasec (abfd)->size =  NBPG * u.u_dsize
 180 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 181     - NBPG * u.u_tsize
 182 #endif
 183       ;
 184   core_stacksec (abfd)->size = NBPG * u.u_ssize;
 185   core_regsec (abfd)->size = NBPG * UPAGES; /* Larger than sizeof struct u */
 186
 187   /* What a hack... we'd like to steal it from the exec file,
 188      since the upage does not seem to provide it.  FIXME.  */
 189 #ifdef HOST_DATA_START_ADDR
 190   core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
 191 #else
 192   core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
 193 #endif
 194
 195 #ifdef HOST_STACK_START_ADDR
 196   core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
 197 #else
 198   core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
 199 #endif
 200
 201   /* This is tricky.  As the "register section", we give them the entire
 202      upage and stack.  u.u_ar0 points to where "register 0" is stored.
 203      There are two tricks with this, though.  One is that the rest of the
 204      registers might be at positive or negative (or both) displacements
 205      from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
 206      in kernel memory, and on other systems it is an offset from the beginning
 207      of the `struct user'.
 208
 209      As a practical matter, we don't know where the registers actually are,
 210      so we have to pass the whole area to GDB.  We encode the value of u_ar0
 211      by setting the .regs section up so that its virtual memory address
 212      0 is at the place pointed to by u_ar0 (by setting the vma of the start
 213      of the section to -u_ar0).  GDB uses this info to locate the regs,
 214      using minor trickery to get around the offset-or-absolute-addr problem.  */
 215   core_regsec (abfd)->vma = - (bfd_vma) (unsigned long) u.u_ar0;
 216
 217   core_datasec (abfd)->filepos = NBPG * UPAGES;
 218   core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
 219 #ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
 220     - NBPG * u.u_tsize
 221 #endif
 222       ;
 223   core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
 224
 225   /* Align to word at least */
 226   core_stacksec (abfd)->alignment_power = 2;
 227   core_datasec (abfd)->alignment_power = 2;
 228   core_regsec (abfd)->alignment_power = 2;
 229
 230   return abfd->xvec;
 231
 232  fail:
 233   bfd_release (abfd, abfd->tdata.any);
 234   abfd->tdata.any = NULL;
 235   bfd_section_list_clear (abfd);
 236   return NULL;
 237 }
 238
 239 char *
 240 trad_unix_core_file_failing_command (abfd)
 241      bfd *abfd;
 242 {
 243 #ifndef NO_CORE_COMMAND
 244   char *com = abfd->tdata.trad_core_data->u.u_comm;
 245   if (*com)
 246     return com;
 247   else
 248 #endif
 249     return 0;
 250 }
 251
 252 int
 253 trad_unix_core_file_failing_signal (ignore_abfd)
 254      bfd *ignore_abfd ATTRIBUTE_UNUSED;
 255 {
 256 #ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
 257   return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
 258 #else
 259   return -1;            /* FIXME, where is it? */
 260 #endif
 261 }
 262 \f
 263 /* If somebody calls any byte-swapping routines, shoot them.  */
 264 static void
 265 swap_abort ()
 266 {
 267   abort (); /* This way doesn't require any declaration for ANSI to fuck up */
 268 }
 269
 270 #define NO_GET ((bfd_vma (*) (const void *)) swap_abort)
 271 #define NO_PUT ((void (*) (bfd_vma, void *)) swap_abort)
 272 #define NO_GETS ((bfd_signed_vma (*) (const void *)) swap_abort)
 273 #define NO_GET64 ((bfd_uint64_t (*) (const void *)) swap_abort)
 274 #define NO_PUT64 ((void (*) (bfd_uint64_t, void *)) swap_abort)
 275 #define NO_GETS64 ((bfd_int64_t (*) (const void *)) swap_abort)
 276
 277 const bfd_target trad_core_vec =
 278   {
 279     "trad-core",
 280     bfd_target_unknown_flavour,
 281     BFD_ENDIAN_UNKNOWN,         /* target byte order */
 282     BFD_ENDIAN_UNKNOWN,         /* target headers byte order */
 283     (HAS_RELOC | EXEC_P |       /* object flags */
 284      HAS_LINENO | HAS_DEBUG |
 285      HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
 286     (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
 287     0,                          /* symbol prefix */
 288     ' ',                        /* ar_pad_char */
 289     16,                         /* ar_max_namelen */
 290     0,                          /* match priority.  */
 291     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit data */
 292     NO_GET, NO_GETS, NO_PUT,            /* 32 bit data */
 293     NO_GET, NO_GETS, NO_PUT,            /* 16 bit data */
 294     NO_GET64, NO_GETS64, NO_PUT64,      /* 64 bit hdrs */
 295     NO_GET, NO_GETS, NO_PUT,            /* 32 bit hdrs */
 296     NO_GET, NO_GETS, NO_PUT,            /* 16 bit hdrs */
 297
 298     {                           /* bfd_check_format */
 299       _bfd_dummy_target,                /* unknown format */
 300       _bfd_dummy_target,                /* object file */
 301       _bfd_dummy_target,                /* archive */
 302       trad_unix_core_file_p             /* a core file */
 303     },
 304     {                           /* bfd_set_format */
 305       bfd_false, bfd_false,
 306       bfd_false, bfd_false
 307     },
 308     {                           /* bfd_write_contents */
 309       bfd_false, bfd_false,
 310       bfd_false, bfd_false
 311     },
 312
 313     BFD_JUMP_TABLE_GENERIC (_bfd_generic),
 314     BFD_JUMP_TABLE_COPY (_bfd_generic),
 315     BFD_JUMP_TABLE_CORE (trad_unix),
 316     BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
 317     BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
 318     BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
 319     BFD_JUMP_TABLE_WRITE (_bfd_generic),
 320     BFD_JUMP_TABLE_LINK (_bfd_nolink),
 321     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
 322
 323     NULL,
 324
 325     (PTR) 0                     /* backend_data */
 326   };