1 /* BFD back-end for Intel 386 COFF files (DJGPP variant with a stub).
2 Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2006, 2007
3 Free Software Foundation, Inc.
4 Written by Robert Hoehne.
6 This file is part of BFD, the Binary File Descriptor library.
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 3 of the License, or
11 (at your option) any later version.
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.
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., 51 Franklin Street - Fifth Floor, Boston,
21 MA 02110-1301, USA. */
23 /* This file handles now also stubbed coff images. The stub is a small
24 DOS executable program before the coff image to load it in memory
25 and execute it. This is needed, because DOS cannot run coff files.
27 All the functions below are called by the corresponding functions
29 The only thing what they do is to adjust the information stored in
30 the COFF file which are offset into the file.
31 This is needed, because DJGPP uses a very special way to load and run
32 the coff image. It loads the image in memory and assumes then, that the
33 image had no stub by using the filepointers as pointers in the coff
34 image and NOT in the file.
36 To be compatible with any existing executables I have fixed this
37 here and NOT in the DJGPP startup code. */
39 #define TARGET_SYM go32stubbedcoff_vec
40 #define TARGET_NAME "coff-go32-exe"
41 #define TARGET_UNDERSCORE '_'
43 #define COFF_LONG_SECTION_NAMES
44 #define COFF_SUPPORT_GNU_LINKONCE
45 #define COFF_LONG_FILENAMES
47 #define COFF_SECTION_ALIGNMENT_ENTRIES \
48 { COFF_SECTION_NAME_EXACT_MATCH (".data"), \
49 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
50 { COFF_SECTION_NAME_EXACT_MATCH (".text"), \
51 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 4 }, \
52 { COFF_SECTION_NAME_PARTIAL_MATCH (".debug"), \
53 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }, \
54 { COFF_SECTION_NAME_PARTIAL_MATCH (".gnu.linkonce.wi"), \
55 COFF_ALIGNMENT_FIELD_EMPTY, COFF_ALIGNMENT_FIELD_EMPTY, 0 }
59 /* At first the prototypes. */
62 adjust_filehdr_in_post
PARAMS ((bfd
*, PTR
, PTR
));
64 adjust_filehdr_out_pre
PARAMS ((bfd
*, PTR
, PTR
));
66 adjust_filehdr_out_post
PARAMS ((bfd
*, PTR
, PTR
));
68 adjust_scnhdr_in_post
PARAMS ((bfd
*, PTR
, PTR
));
70 adjust_scnhdr_out_pre
PARAMS ((bfd
*, PTR
, PTR
));
72 adjust_scnhdr_out_post
PARAMS ((bfd
*, PTR
, PTR
));
74 adjust_aux_in_post
PARAMS ((bfd
*, PTR
, int, int, int, int, PTR
));
76 adjust_aux_out_pre
PARAMS ((bfd
*, PTR
, int, int, int, int, PTR
));
78 adjust_aux_out_post
PARAMS ((bfd
*, PTR
, int, int, int, int, PTR
));
80 create_go32_stub
PARAMS ((bfd
*));
82 /* All that ..._PRE and ...POST functions are called from the corresponding
83 coff_swap... functions. The ...PRE functions are called at the beginning
84 of the function and the ...POST functions at the end of the swap routines. */
86 #define COFF_ADJUST_FILEHDR_IN_POST adjust_filehdr_in_post
87 #define COFF_ADJUST_FILEHDR_OUT_PRE adjust_filehdr_out_pre
88 #define COFF_ADJUST_FILEHDR_OUT_POST adjust_filehdr_out_post
90 #define COFF_ADJUST_SCNHDR_IN_POST adjust_scnhdr_in_post
91 #define COFF_ADJUST_SCNHDR_OUT_PRE adjust_scnhdr_out_pre
92 #define COFF_ADJUST_SCNHDR_OUT_POST adjust_scnhdr_out_post
94 #define COFF_ADJUST_AUX_IN_POST adjust_aux_in_post
95 #define COFF_ADJUST_AUX_OUT_PRE adjust_aux_out_pre
96 #define COFF_ADJUST_AUX_OUT_POST adjust_aux_out_post
99 go32_stubbed_coff_bfd_copy_private_bfd_data
PARAMS ((bfd
*, bfd
*));
101 #define coff_bfd_copy_private_bfd_data go32_stubbed_coff_bfd_copy_private_bfd_data
103 #include "coff-i386.c"
105 /* I hold in the usrdata the stub. */
106 #define bfd_coff_go32stub bfd_usrdata
108 /* This macro is used, because I cannot assume the endianess of the
110 #define _H(index) (H_GET_16 (abfd, (header+index*2)))
112 /* These bytes are a 2048-byte DOS executable, which loads the COFF
113 image into memory and then runs it. It is called 'stub'. */
115 static const unsigned char stub_bytes
[STUBSIZE
] =
117 #include "go32stub.h"
121 I have not commented each swap function below, because the
122 technique is in any function the same. For the ...in function,
123 all the pointers are adjusted by adding STUBSIZE and for the
124 ...out function, it is subtracted first and after calling the
125 standard swap function it is reset to the old value. */
127 /* This macro is used for adjusting the filepointers, which
128 is done only, if the pointer is nonzero. */
130 #define ADJUST_VAL(val,diff) \
131 if (val != 0) val += diff
134 adjust_filehdr_in_post (abfd
, src
, dst
)
139 FILHDR
*filehdr_src
= (FILHDR
*) src
;
140 struct internal_filehdr
*filehdr_dst
= (struct internal_filehdr
*) dst
;
142 ADJUST_VAL (filehdr_dst
->f_symptr
, STUBSIZE
);
144 /* Save now the stub to be used later. FIXME: Memory leak as the caller
145 coff_object_p does bfd_release afterwards. */
146 bfd_coff_go32stub (abfd
) = bfd_malloc ((bfd_size_type
) STUBSIZE
);
148 /* Since this function returns no status, I do not set here
150 That means, before the use of bfd_coff_go32stub (), this value
151 should be checked if it is != NULL. */
152 if (bfd_coff_go32stub (abfd
) == NULL
)
154 memcpy (bfd_coff_go32stub (abfd
), filehdr_src
->stub
, STUBSIZE
);
158 adjust_filehdr_out_pre (abfd
, in
, out
)
163 struct internal_filehdr
*filehdr_in
= (struct internal_filehdr
*) in
;
164 FILHDR
*filehdr_out
= (FILHDR
*) out
;
166 /* Generate the stub. */
167 create_go32_stub (abfd
);
169 /* Copy the stub to the file header. */
170 if (bfd_coff_go32stub (abfd
) != NULL
)
171 memcpy (filehdr_out
->stub
, bfd_coff_go32stub (abfd
), STUBSIZE
);
173 /* Use the default. */
174 memcpy (filehdr_out
->stub
, stub_bytes
, STUBSIZE
);
176 ADJUST_VAL (filehdr_in
->f_symptr
, -STUBSIZE
);
180 adjust_filehdr_out_post (abfd
, in
, out
)
181 bfd
*abfd ATTRIBUTE_UNUSED
;
183 PTR out ATTRIBUTE_UNUSED
;
185 struct internal_filehdr
*filehdr_in
= (struct internal_filehdr
*) in
;
186 /* Undo the above change. */
187 ADJUST_VAL (filehdr_in
->f_symptr
, STUBSIZE
);
191 adjust_scnhdr_in_post (abfd
, ext
, in
)
192 bfd
*abfd ATTRIBUTE_UNUSED
;
193 PTR ext ATTRIBUTE_UNUSED
;
196 struct internal_scnhdr
*scnhdr_int
= (struct internal_scnhdr
*) in
;
198 ADJUST_VAL (scnhdr_int
->s_scnptr
, STUBSIZE
);
199 ADJUST_VAL (scnhdr_int
->s_relptr
, STUBSIZE
);
200 ADJUST_VAL (scnhdr_int
->s_lnnoptr
, STUBSIZE
);
204 adjust_scnhdr_out_pre (abfd
, in
, out
)
205 bfd
*abfd ATTRIBUTE_UNUSED
;
207 PTR out ATTRIBUTE_UNUSED
;
209 struct internal_scnhdr
*scnhdr_int
= (struct internal_scnhdr
*) in
;
211 ADJUST_VAL (scnhdr_int
->s_scnptr
, -STUBSIZE
);
212 ADJUST_VAL (scnhdr_int
->s_relptr
, -STUBSIZE
);
213 ADJUST_VAL (scnhdr_int
->s_lnnoptr
, -STUBSIZE
);
217 adjust_scnhdr_out_post (abfd
, in
, out
)
218 bfd
*abfd ATTRIBUTE_UNUSED
;
220 PTR out ATTRIBUTE_UNUSED
;
222 struct internal_scnhdr
*scnhdr_int
= (struct internal_scnhdr
*) in
;
224 ADJUST_VAL (scnhdr_int
->s_scnptr
, STUBSIZE
);
225 ADJUST_VAL (scnhdr_int
->s_relptr
, STUBSIZE
);
226 ADJUST_VAL (scnhdr_int
->s_lnnoptr
, STUBSIZE
);
230 adjust_aux_in_post (abfd
, ext1
, type
, class, indx
, numaux
, in1
)
231 bfd
*abfd ATTRIBUTE_UNUSED
;
232 PTR ext1 ATTRIBUTE_UNUSED
;
235 int indx ATTRIBUTE_UNUSED
;
236 int numaux ATTRIBUTE_UNUSED
;
239 union internal_auxent
*in
= (union internal_auxent
*) in1
;
241 if (class == C_BLOCK
|| class == C_FCN
|| ISFCN (type
) || ISTAG (class))
243 ADJUST_VAL (in
->x_sym
.x_fcnary
.x_fcn
.x_lnnoptr
, STUBSIZE
);
248 adjust_aux_out_pre (abfd
, inp
, type
, class, indx
, numaux
, extp
)
249 bfd
*abfd ATTRIBUTE_UNUSED
;
253 int indx ATTRIBUTE_UNUSED
;
254 int numaux ATTRIBUTE_UNUSED
;
255 PTR extp ATTRIBUTE_UNUSED
;
257 union internal_auxent
*in
= (union internal_auxent
*) inp
;
259 if (class == C_BLOCK
|| class == C_FCN
|| ISFCN (type
) || ISTAG (class))
261 ADJUST_VAL (in
->x_sym
.x_fcnary
.x_fcn
.x_lnnoptr
, -STUBSIZE
);
266 adjust_aux_out_post (abfd
, inp
, type
, class, indx
, numaux
, extp
)
267 bfd
*abfd ATTRIBUTE_UNUSED
;
271 int indx ATTRIBUTE_UNUSED
;
272 int numaux ATTRIBUTE_UNUSED
;
273 PTR extp ATTRIBUTE_UNUSED
;
275 union internal_auxent
*in
= (union internal_auxent
*) inp
;
277 if (class == C_BLOCK
|| class == C_FCN
|| ISFCN (type
) || ISTAG (class))
279 ADJUST_VAL (in
->x_sym
.x_fcnary
.x_fcn
.x_lnnoptr
, STUBSIZE
);
283 /* That's the function, which creates the stub. There are
284 different cases from where the stub is taken.
285 At first the environment variable $(GO32STUB) is checked and then
286 $(STUB) if it was not set.
287 If it exists and points to a valid stub the stub is taken from
288 that file. This file can be also a whole executable file, because
289 the stub is computed from the exe information at the start of that
292 If there was any error, the standard stub (compiled in this file)
296 create_go32_stub (abfd
)
299 /* Do it only once. */
300 if (bfd_coff_go32stub (abfd
) == NULL
)
305 unsigned char header
[10];
307 unsigned long coff_start
;
310 /* Check at first the environment variable $(GO32STUB). */
311 stub
= getenv ("GO32STUB");
312 /* Now check the environment variable $(STUB). */
314 stub
= getenv ("STUB");
317 if (stat (stub
, &st
) != 0)
320 f
= open (stub
, O_RDONLY
| O_BINARY
);
322 f
= open (stub
, O_RDONLY
);
326 if (read (f
, &header
, sizeof (header
)) < 0)
331 if (_H (0) != 0x5a4d) /* It is not an exe file. */
336 /* Compute the size of the stub (it is every thing up
337 to the beginning of the coff image). */
338 coff_start
= (long) _H (2) * 512L;
340 coff_start
+= (long) _H (1) - 512L;
342 /* Currently there is only a fixed stub size of 2048 bytes
344 if (coff_start
!= 2048)
349 exe_start
= _H (4) * 16;
350 if ((long) lseek (f
, exe_start
, SEEK_SET
) != exe_start
)
355 if (read (f
, &magic
, 8) != 8)
360 if (! CONST_STRNEQ (magic
, "go32stub"))
365 /* Now we found a correct stub (hopefully). */
366 bfd_coff_go32stub (abfd
)
367 = (PTR
) bfd_alloc (abfd
, (bfd_size_type
) coff_start
);
368 if (bfd_coff_go32stub (abfd
) == NULL
)
373 lseek (f
, 0L, SEEK_SET
);
374 if ((unsigned long) read (f
, bfd_coff_go32stub (abfd
), coff_start
)
377 bfd_release (abfd
, bfd_coff_go32stub (abfd
));
378 bfd_coff_go32stub (abfd
) = NULL
;
383 /* There was something wrong above, so use now the standard builtin
385 if (bfd_coff_go32stub (abfd
) == NULL
)
387 bfd_coff_go32stub (abfd
)
388 = (PTR
) bfd_alloc (abfd
, (bfd_size_type
) STUBSIZE
);
389 if (bfd_coff_go32stub (abfd
) == NULL
)
391 memcpy (bfd_coff_go32stub (abfd
), stub_bytes
, STUBSIZE
);
395 /* If ibfd was a stubbed coff image, copy the stub from that bfd
399 go32_stubbed_coff_bfd_copy_private_bfd_data (ibfd
, obfd
)
403 /* Check if both are the same targets. */
404 if (ibfd
->xvec
!= obfd
->xvec
)
407 /* Check if we have a source stub. */
408 if (bfd_coff_go32stub (ibfd
) == NULL
)
411 /* As adjust_filehdr_out_pre may get called only after this function,
412 optionally allocate the output stub. */
413 if (bfd_coff_go32stub (obfd
) == NULL
)
414 bfd_coff_go32stub (obfd
) = bfd_alloc (obfd
, (bfd_size_type
) STUBSIZE
);
416 /* Now copy the stub. */
417 if (bfd_coff_go32stub (obfd
) != NULL
)
418 memcpy (bfd_coff_go32stub (obfd
), bfd_coff_go32stub (ibfd
), STUBSIZE
);