trad-core.c revision 78828 
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
4   Free Software Foundation, Inc.
5   Written by John Gilmore of Cygnus Support.
6
7This file is part of BFD, the Binary File Descriptor library.
8
9This program is free software; you can redistribute it and/or modify
10it under the terms of the GNU General Public License as published by
11the Free Software Foundation; either version 2 of the License, or
12(at your option) any later version.
13
14This program is distributed in the hope that it will be useful,
15but WITHOUT ANY WARRANTY; without even the implied warranty of
16MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17GNU General Public License for more details.
18
19You should have received a copy of the GNU General Public License
20along with this program; if not, write to the Free Software
21Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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
65const bfd_target *trad_unix_core_file_p PARAMS ((bfd *abfd));
66char *		trad_unix_core_file_failing_command PARAMS ((bfd *abfd));
67int		trad_unix_core_file_failing_signal PARAMS ((bfd *abfd));
68boolean		trad_unix_core_file_matches_executable_p
69			 PARAMS ((bfd *core_bfd, bfd *exec_bfd));
70static void	swap_abort PARAMS ((void));
71
72/* Handle 4.2-style (and perhaps also sysV-style) core dump file.  */
73
74/* ARGSUSED */
75const bfd_target *
76trad_unix_core_file_p (abfd)
77     bfd *abfd;
78
79{
80  int val;
81  struct user u;
82  struct trad_core_struct *rawptr;
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, TRAD_CORE_USER_OFFSET, SEEK_SET) != 0)
87    return 0;
88#endif
89
90  val = bfd_read ((void *)&u, 1, 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    FILE *stream = bfd_cache_lookup (abfd);
113    struct stat statbuf;
114    if (stream == NULL)
115      return 0;
116    if (fstat (fileno (stream), &statbuf) < 0)
117      {
118	bfd_set_error (bfd_error_system_call);
119	return 0;
120      }
121    if ((unsigned long) (NBPG * (UPAGES + u.u_dsize
122#ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
123				 - u.u_tsize
124#endif
125				 + u.u_ssize))
126	> (unsigned long) statbuf.st_size)
127      {
128	bfd_set_error (bfd_error_wrong_format);
129	return 0;
130      }
131#ifndef TRAD_CORE_ALLOW_ANY_EXTRA_SIZE
132    if ((unsigned long) (NBPG * (UPAGES + u.u_dsize + u.u_ssize)
133#ifdef TRAD_CORE_EXTRA_SIZE_ALLOWED
134	/* Some systems write the file too big.  */
135			 + TRAD_CORE_EXTRA_SIZE_ALLOWED
136#endif
137			 )
138	< (unsigned long) statbuf.st_size)
139      {
140	/* The file is too big.  Maybe it's not a core file
141	   or we otherwise have bad values for u_dsize and u_ssize).  */
142	bfd_set_error (bfd_error_wrong_format);
143	return 0;
144      }
145#endif
146  }
147
148  /* OK, we believe you.  You're a core file (sure, sure).  */
149
150  /* Allocate both the upage and the struct core_data at once, so
151     a single free() will free them both.  */
152  rawptr = (struct trad_core_struct *)
153		bfd_zmalloc (sizeof (struct trad_core_struct));
154  if (rawptr == NULL)
155    return 0;
156
157  abfd->tdata.trad_core_data = rawptr;
158
159  rawptr->u = u; /*Copy the uarea into the tdata part of the bfd */
160
161  /* Create the sections.  This is raunchy, but bfd_close wants to free
162     them separately.  */
163
164  core_stacksec(abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
165  if (core_stacksec (abfd) == NULL)
166    return NULL;
167  core_datasec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
168  if (core_datasec (abfd) == NULL)
169    return NULL;
170  core_regsec (abfd) = (asection *) bfd_zalloc (abfd, sizeof (asection));
171  if (core_regsec (abfd) == NULL)
172    return NULL;
173
174  core_stacksec (abfd)->name = ".stack";
175  core_datasec (abfd)->name = ".data";
176  core_regsec (abfd)->name = ".reg";
177
178  core_stacksec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
179  core_datasec (abfd)->flags = SEC_ALLOC + SEC_LOAD + SEC_HAS_CONTENTS;
180  core_regsec (abfd)->flags = SEC_HAS_CONTENTS;
181
182  core_datasec (abfd)->_raw_size =  NBPG * u.u_dsize
183#ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
184    - NBPG * u.u_tsize
185#endif
186      ;
187  core_stacksec (abfd)->_raw_size = NBPG * u.u_ssize;
188  core_regsec (abfd)->_raw_size = NBPG * UPAGES; /* Larger than sizeof struct u */
189
190  /* What a hack... we'd like to steal it from the exec file,
191     since the upage does not seem to provide it.  FIXME.  */
192#ifdef HOST_DATA_START_ADDR
193  core_datasec (abfd)->vma = HOST_DATA_START_ADDR;
194#else
195  core_datasec (abfd)->vma = HOST_TEXT_START_ADDR + (NBPG * u.u_tsize);
196#endif
197
198#ifdef HOST_STACK_START_ADDR
199  core_stacksec (abfd)->vma = HOST_STACK_START_ADDR;
200#else
201  core_stacksec (abfd)->vma = HOST_STACK_END_ADDR - (NBPG * u.u_ssize);
202#endif
203
204  /* This is tricky.  As the "register section", we give them the entire
205     upage and stack.  u.u_ar0 points to where "register 0" is stored.
206     There are two tricks with this, though.  One is that the rest of the
207     registers might be at positive or negative (or both) displacements
208     from *u_ar0.  The other is that u_ar0 is sometimes an absolute address
209     in kernel memory, and on other systems it is an offset from the beginning
210     of the `struct user'.
211
212     As a practical matter, we don't know where the registers actually are,
213     so we have to pass the whole area to GDB.  We encode the value of u_ar0
214     by setting the .regs section up so that its virtual memory address
215     0 is at the place pointed to by u_ar0 (by setting the vma of the start
216     of the section to -u_ar0).  GDB uses this info to locate the regs,
217     using minor trickery to get around the offset-or-absolute-addr problem.  */
218  core_regsec (abfd)->vma = - (bfd_vma) u.u_ar0;
219
220  core_datasec (abfd)->filepos = NBPG * UPAGES;
221  core_stacksec (abfd)->filepos = (NBPG * UPAGES) + NBPG * u.u_dsize
222#ifdef TRAD_CORE_DSIZE_INCLUDES_TSIZE
223    - NBPG * u.u_tsize
224#endif
225      ;
226  core_regsec (abfd)->filepos = 0; /* Register segment is the upage */
227
228  /* Align to word at least */
229  core_stacksec (abfd)->alignment_power = 2;
230  core_datasec (abfd)->alignment_power = 2;
231  core_regsec (abfd)->alignment_power = 2;
232
233  abfd->sections = core_stacksec (abfd);
234  core_stacksec (abfd)->next = core_datasec (abfd);
235  core_datasec (abfd)->next = core_regsec (abfd);
236  abfd->section_count = 3;
237
238  return abfd->xvec;
239}
240
241char *
242trad_unix_core_file_failing_command (abfd)
243     bfd *abfd;
244{
245#ifndef NO_CORE_COMMAND
246  char *com = abfd->tdata.trad_core_data->u.u_comm;
247  if (*com)
248    return com;
249  else
250#endif
251    return 0;
252}
253
254/* ARGSUSED */
255int
256trad_unix_core_file_failing_signal (ignore_abfd)
257     bfd *ignore_abfd ATTRIBUTE_UNUSED;
258{
259#ifdef TRAD_UNIX_CORE_FILE_FAILING_SIGNAL
260  return TRAD_UNIX_CORE_FILE_FAILING_SIGNAL(ignore_abfd);
261#else
262  return -1;		/* FIXME, where is it? */
263#endif
264}
265
266/* ARGSUSED */
267boolean
268trad_unix_core_file_matches_executable_p  (core_bfd, exec_bfd)
269     bfd *core_bfd ATTRIBUTE_UNUSED;
270     bfd *exec_bfd ATTRIBUTE_UNUSED;
271{
272  return true;		/* FIXME, We have no way of telling at this point */
273}
274
275/* If somebody calls any byte-swapping routines, shoot them.  */
276static void
277swap_abort ()
278{
279  abort (); /* This way doesn't require any declaration for ANSI to fuck up */
280}
281#define	NO_GET	((bfd_vma (*) PARAMS ((   const bfd_byte *))) swap_abort )
282#define	NO_PUT	((void    (*) PARAMS ((bfd_vma, bfd_byte *))) swap_abort )
283#define	NO_SIGNED_GET \
284  ((bfd_signed_vma (*) PARAMS ((const bfd_byte *))) swap_abort )
285
286const bfd_target trad_core_vec =
287  {
288    "trad-core",
289    bfd_target_unknown_flavour,
290    BFD_ENDIAN_UNKNOWN,		/* target byte order */
291    BFD_ENDIAN_UNKNOWN,		/* target headers byte order */
292    (HAS_RELOC | EXEC_P |	/* object flags */
293     HAS_LINENO | HAS_DEBUG |
294     HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
295    (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC), /* section flags */
296    0,			                                   /* symbol prefix */
297    ' ',						   /* ar_pad_char */
298    16,							   /* ar_max_namelen */
299    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 64 bit data */
300    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 32 bit data */
301    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 16 bit data */
302    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 64 bit hdrs */
303    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 32 bit hdrs */
304    NO_GET, NO_SIGNED_GET, NO_PUT,	/* 16 bit hdrs */
305
306    {				/* bfd_check_format */
307     _bfd_dummy_target,		/* unknown format */
308     _bfd_dummy_target,		/* object file */
309     _bfd_dummy_target,		/* archive */
310     trad_unix_core_file_p	/* a core file */
311    },
312    {				/* bfd_set_format */
313     bfd_false, bfd_false,
314     bfd_false, bfd_false
315    },
316    {				/* bfd_write_contents */
317     bfd_false, bfd_false,
318     bfd_false, bfd_false
319    },
320
321       BFD_JUMP_TABLE_GENERIC (_bfd_generic),
322       BFD_JUMP_TABLE_COPY (_bfd_generic),
323       BFD_JUMP_TABLE_CORE (trad_unix),
324       BFD_JUMP_TABLE_ARCHIVE (_bfd_noarchive),
325       BFD_JUMP_TABLE_SYMBOLS (_bfd_nosymbols),
326       BFD_JUMP_TABLE_RELOCS (_bfd_norelocs),
327       BFD_JUMP_TABLE_WRITE (_bfd_generic),
328       BFD_JUMP_TABLE_LINK (_bfd_nolink),
329       BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
330
331    NULL,
332
333    (PTR) 0			/* backend_data */
334};
335