1 /* Generic target-file-type support for the BFD library.
2 Copyright 1990, 1991, 1992 Free Software Foundation, Inc.
3 Written by Cygnus Support.
5 This file is part of BFD, the Binary File Descriptor library.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
30 Each port of BFD to a different machine requries the creation
31 of a target back end. All the back end provides to the root
32 part of BFD is a structure containing pointers to functions
33 which perform certain low level operations on files. BFD
34 translates the applications's requests through a pointer into
35 calls to the back end routines.
37 When a file is opened with <<bfd_openr>>, its format and
38 target are unknown. BFD uses various mechanisms to determine
39 how to interpret the file. The operations performed are:
41 o First a BFD is created by calling the internal routine
42 <<new_bfd>>, then <<bfd_find_target>> is called with the
43 target string supplied to <<bfd_openr>> and the new BFD pointer.
45 o If a null target string was provided to <<bfd_find_target>>,
46 it looks up the environment variable <<GNUTARGET>> and uses
47 that as the target string.
49 o If the target string is still NULL, or the target string is
50 <<default>>, then the first item in the target vector is used
51 as the target type, and <<target_defaulted>> is set to
52 cause <<bfd_check_format>> to loop through all the targets.
53 @xref{bfd_target}. @xref{Formats}.
55 o Otherwise, the elements in the target vector are inspected
56 one by one, until a match on target name is found. When found,
59 o Otherwise the error <<invalid_target>> is returned to
62 o <<bfd_openr>> attempts to open the file using
63 <<bfd_open_file>>, and returns the BFD.
65 Once the BFD has been opened and the target selected, the file
66 format may be determined. This is done by calling
67 <<bfd_check_format>> on the BFD with a suggested format.
68 If <<target_defaulted>> has been set, each possible target
69 type is tried to see if it recognizes the specified format. The
70 routine returns <<true>> when the application guesses right.
80 bfd_target, , Targets, Targets
86 This structure contains everything that BFD knows about a
87 target. It includes things like its byte order, name, what
88 routines to call to do various operations, etc.
90 Every BFD points to a target structure with its <<xvec>>
93 Shortcut for declaring fields which are prototyped function
94 pointers, while avoiding anguish on compilers that don't
97 .#define SDEF(ret, name, arglist) \
98 . PROTO(ret,(*name),arglist)
99 .#define SDEF_FMT(ret, name, arglist) \
100 . PROTO(ret,(*name[bfd_type_end]),arglist)
102 These macros are used to dispatch to functions through the
103 bfd_target vector. They are used in a number of macros further
104 down in @file{bfd.h}, and are also used when calling various
105 routines by hand inside the BFD implementation. The "arglist"
106 argument must be parenthesized; it contains all the arguments
107 to the called function.
109 They make the documentation (more) unpleasant to read, so if
110 someone wants to fix this and not break the above, please do.
112 .#define BFD_SEND(bfd, message, arglist) \
113 . ((*((bfd)->xvec->message)) arglist)
115 For operations which index on the BFD format
117 .#define BFD_SEND_FMT(bfd, message, arglist) \
118 . (((bfd)->xvec->message[(int)((bfd)->format)]) arglist)
120 This is the struct which defines the type of BFD this is. The
121 <<xvec>> member of the struct <<bfd>> itself points here. Each
122 module that implements access to a different target under BFD,
123 defines one of these.
126 FIXME, these names should be rationalised with the names of
127 the entry points which call them. Too bad we can't have one
128 macro to define them both!
130 .typedef struct bfd_target
133 Identifies the kind of target, eg SunOS4, Ultrix, etc.
137 The "flavour" of a back end is a general indication about the contents
140 . enum target_flavour {
141 . bfd_target_unknown_flavour,
142 . bfd_target_aout_flavour,
143 . bfd_target_coff_flavour,
144 . bfd_target_elf_flavour,
145 . bfd_target_ieee_flavour,
146 . bfd_target_oasys_flavour,
147 . bfd_target_tekhex_flavour,
148 . bfd_target_srec_flavour,
149 . bfd_target_hppa_flavour} flavour;
151 The order of bytes within the data area of a file.
153 . boolean byteorder_big_p;
155 The order of bytes within the header parts of a file.
157 . boolean header_byteorder_big_p;
159 This is a mask of all the flags which an executable may have set -
160 from the set <<NO_FLAGS>>, <<HAS_RELOC>>, ...<<D_PAGED>>.
162 . flagword object_flags;
164 This is a mask of all the flags which a section may have set - from
165 the set <<SEC_NO_FLAGS>>, <<SEC_ALLOC>>, ...<<SET_NEVER_LOAD>>.
167 . flagword section_flags;
169 The pad character for filenames within an archive header.
173 The maximum number of characters in an archive header.
175 . unsigned short ar_max_namelen;
177 The minimum alignment restriction for any section.
179 . unsigned int align_power_min;
181 Entries for byte swapping for data. These are different to the other
182 entry points, since they don't take BFD as first arg. Certain other handlers
185 . SDEF (bfd_vma, bfd_getx64, (bfd_byte *));
186 . SDEF (void, bfd_putx64, (bfd_vma, bfd_byte *));
187 . SDEF (bfd_vma, bfd_getx32, (bfd_byte *));
188 . SDEF (void, bfd_putx32, (bfd_vma, bfd_byte *));
189 . SDEF (bfd_vma, bfd_getx16, (bfd_byte *));
190 . SDEF (void, bfd_putx16, (bfd_vma, bfd_byte *));
192 Byte swapping for the headers
194 . SDEF (bfd_vma, bfd_h_getx64, (bfd_byte *));
195 . SDEF (void, bfd_h_putx64, (bfd_vma, bfd_byte *));
196 . SDEF (bfd_vma, bfd_h_getx32, (bfd_byte *));
197 . SDEF (void, bfd_h_putx32, (bfd_vma, bfd_byte *));
198 . SDEF (bfd_vma, bfd_h_getx16, (bfd_byte *));
199 . SDEF (void, bfd_h_putx16, (bfd_vma, bfd_byte *));
201 Format dependent routines, these turn into vectors of entry points
202 within the target vector structure; one for each format to check.
204 Check the format of a file being read. Return bfd_target * or zero.
206 . SDEF_FMT (struct bfd_target *, _bfd_check_format, (bfd *));
208 Set the format of a file being written.
210 . SDEF_FMT (boolean, _bfd_set_format, (bfd *));
212 Write cached information into a file being written, at bfd_close.
214 . SDEF_FMT (boolean, _bfd_write_contents, (bfd *));
216 The following functions are defined in <<JUMP_TABLE>>. The idea is
217 that the back end writer of <<foo>> names all the routines
218 <<foo_>>@var{entry_point}, <<JUMP_TABLE>> will built the entries
219 in this structure in the right order.
221 Core file entry points
223 . SDEF (char *, _core_file_failing_command, (bfd *));
224 . SDEF (int, _core_file_failing_signal, (bfd *));
225 . SDEF (boolean, _core_file_matches_executable_p, (bfd *, bfd *));
229 . SDEF (boolean, _bfd_slurp_armap, (bfd *));
230 . SDEF (boolean, _bfd_slurp_extended_name_table, (bfd *));
231 . SDEF (void, _bfd_truncate_arname, (bfd *, CONST char *, char *));
232 . SDEF (boolean, write_armap, (bfd *arch,
233 . unsigned int elength,
235 . unsigned int orl_count,
240 . SDEF (boolean, _close_and_cleanup, (bfd *));
241 . SDEF (boolean, _bfd_set_section_contents, (bfd *, sec_ptr, PTR,
242 . file_ptr, bfd_size_type));
243 . SDEF (boolean, _bfd_get_section_contents, (bfd *, sec_ptr, PTR,
244 . file_ptr, bfd_size_type));
245 . SDEF (boolean, _new_section_hook, (bfd *, sec_ptr));
247 Symbols and relocations
249 . SDEF (unsigned int, _get_symtab_upper_bound, (bfd *));
250 . SDEF (unsigned int, _bfd_canonicalize_symtab,
251 . (bfd *, struct symbol_cache_entry **));
252 . SDEF (unsigned int, _get_reloc_upper_bound, (bfd *, sec_ptr));
253 . SDEF (unsigned int, _bfd_canonicalize_reloc, (bfd *, sec_ptr, arelent **,
254 . struct symbol_cache_entry**));
255 . SDEF (struct symbol_cache_entry *, _bfd_make_empty_symbol, (bfd *));
256 . SDEF (void, _bfd_print_symbol, (bfd *, PTR, struct symbol_cache_entry *,
257 . bfd_print_symbol_type));
258 .#define bfd_print_symbol(b,p,s,e) BFD_SEND(b, _bfd_print_symbol, (b,p,s,e))
259 . SDEF (alent *, _get_lineno, (bfd *, struct symbol_cache_entry *));
261 . SDEF (boolean, _bfd_set_arch_mach, (bfd *, enum bfd_architecture,
264 . SDEF (bfd *, openr_next_archived_file, (bfd *arch, bfd *prev));
265 . SDEF (boolean, _bfd_find_nearest_line,
266 . (bfd *abfd, struct sec *section,
267 . struct symbol_cache_entry **symbols,bfd_vma offset,
268 . CONST char **file, CONST char **func, unsigned int *line));
269 . SDEF (int, _bfd_stat_arch_elt, (bfd *, struct stat *));
271 . SDEF (int, _bfd_sizeof_headers, (bfd *, boolean));
273 . SDEF (void, _bfd_debug_info_start, (bfd *));
274 . SDEF (void, _bfd_debug_info_end, (bfd *));
275 . SDEF (void, _bfd_debug_info_accumulate, (bfd *, struct sec *));
276 . SDEF (bfd_byte *, _bfd_get_relocated_section_contents, (bfd*,struct bfd_seclet_struct *, bfd_byte *data));
277 . SDEF (boolean,_bfd_relax_section,(bfd *, struct sec *, struct symbol_cache_entry **));
278 Special entry points for gdb to swap in coff symbol table parts
280 . SDEF(void, _bfd_coff_swap_aux_in,(
287 . SDEF(void, _bfd_coff_swap_sym_in,(
292 . SDEF(void, _bfd_coff_swap_lineno_in, (
298 Special entry points for gas to swap coff parts
300 . SDEF(unsigned int, _bfd_coff_swap_aux_out,(
307 . SDEF(unsigned int, _bfd_coff_swap_sym_out,(
312 . SDEF(unsigned int, _bfd_coff_swap_lineno_out,(
317 . SDEF(unsigned int, _bfd_coff_swap_reloc_out,(
322 . SDEF(unsigned int, _bfd_coff_swap_filehdr_out,(
327 . SDEF(unsigned int, _bfd_coff_swap_aouthdr_out,(
332 . SDEF(unsigned int, _bfd_coff_swap_scnhdr_out,(
337 . {* See documentation on reloc types. *}
338 . SDEF (CONST struct reloc_howto_struct *,
340 . (bfd *abfd, bfd_reloc_code_real_type code));
342 . {* Complete and utter crock, currently used for the assembler
343 . when creating COFF files. *}
344 . SDEF (asymbol *, _bfd_make_debug_symbol, (
347 . unsigned long size));
349 Data for use by back-end routines; e.g., for a.out, includes whether
350 this particular target maps ZMAGIC files contiguously or with text and
351 data separated. Could perhaps also be used to eliminate some of the
352 above COFF-specific fields.
359 /* The default is to define a target_vector containing all the targets.
360 By setting MINIMIZE=1 on the "make" command line, the user can change this
361 to a vector containing just DEFAULT_VECTOR and any required
362 traditional-core-file handler. (This is to save space in the executables.)
363 The config files can also override the default large vector by giving an
364 explicit SELECT_VECS macro. */
366 #if MINIMIZE && defined(DEFAULT_VECTOR) && !defined(SELECT_VECS)
368 #define SELECT_VECS &DEFAULT_VECTOR,&trad_core_vec
370 #define SELECT_VECS &DEFAULT_VECTOR
374 /* All known xvecs. They are listed a second time below, since
375 we can't intermix extern's and initializers. */
376 extern bfd_target ecoff_little_vec
;
377 extern bfd_target ecoff_big_vec
;
378 extern bfd_target sunos_big_vec
;
379 extern bfd_target demo_64_vec
;
380 extern bfd_target srec_vec
;
381 extern bfd_target tekhex_vec
;
382 extern bfd_target a_out_adobe_vec
;
383 extern bfd_target b_out_vec_little_host
;
384 extern bfd_target b_out_vec_big_host
;
385 extern bfd_target icoff_little_vec
;
386 extern bfd_target icoff_big_vec
;
387 extern bfd_target elf_little_vec
;
388 extern bfd_target elf_big_vec
;
389 extern bfd_target ieee_vec
;
390 extern bfd_target oasys_vec
;
391 extern bfd_target m88kbcs_vec
;
392 extern bfd_target m68kcoff_vec
;
393 extern bfd_target i386coff_vec
;
394 extern bfd_target i386aout_vec
;
395 extern bfd_target i386linux_vec
;
396 extern bfd_target a29kcoff_big_vec
;
397 extern bfd_target trad_core_vec
;
398 extern bfd_target rs6000coff_vec
;
399 extern bfd_target h8300coff_vec
;
400 extern bfd_target z8kcoff_vec
;
401 extern bfd_target we32kcoff_vec
;
403 extern bfd_target hppa_vec
;
406 #ifdef DEFAULT_VECTOR
407 extern bfd_target DEFAULT_VECTOR
;
412 bfd_target
*target_vector
[] = {
419 bfd_target
*target_vector
[] = {
421 #ifdef DEFAULT_VECTOR
431 /* We have no oasys tools anymore, so we can't test any of this
432 anymore. If you want to test the stuff yourself, go ahead...
434 Worse, since there is no magic number for archives, there
435 can annoying target mis-matches. */
440 &demo_64_vec
, /* Only compiled if host has long-long support */
452 &b_out_vec_little_host
,
465 NULL
, /* end of list marker */
470 /* default_vector[0] contains either the address of the default vector,
471 if there is one, or zero if there isn't. */
473 bfd_target
*default_vector
[] = {
474 #ifdef DEFAULT_VECTOR
488 Returns a pointer to the transfer vector for the object target
489 named target_name. If target_name is NULL, chooses the one in
490 the environment variable GNUTARGET; if that is null or not
491 defined thenthe first entry in the target list is chosen.
492 Passing in the string "default" or setting the environment
493 variable to "default" will cause the first entry in the target
494 list to be returned, and "target_defaulted" will be set in the
495 BFD. This causes <<bfd_check_format>> to loop over all the
496 targets to find the one that matches the file being read.
499 bfd_target *bfd_find_target(CONST char *, bfd *);
503 DEFUN(bfd_find_target
,(target_name
, abfd
),
504 CONST
char *target_name AND
508 extern char *getenv ();
509 CONST
char *targname
= (target_name
? target_name
:
510 (CONST
char *) getenv ("GNUTARGET"));
512 /* This is safe; the vector cannot be null */
513 if (targname
== NULL
|| !strcmp (targname
, "default")) {
514 abfd
->target_defaulted
= true;
515 return abfd
->xvec
= target_vector
[0];
518 abfd
->target_defaulted
= false;
520 for (target
= &target_vector
[0]; *target
!= NULL
; target
++) {
521 if (!strcmp (targname
, (*target
)->name
))
522 return abfd
->xvec
= *target
;
525 bfd_error
= invalid_target
;
535 This function returns a freshly malloced NULL-terminated
536 vector of the names of all the valid BFD targets. Do not
540 CONST char **bfd_target_list(void);
545 DEFUN_VOID(bfd_target_list
)
549 CONST
char **name_list
, **name_ptr
;
551 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
555 name_list
= (CONST
char **) zalloc ((vec_length
+ 1) * sizeof (char **));
557 if (name_list
== NULL
) {
558 bfd_error
= no_memory
;
562 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
563 *(name_ptr
++) = (*target
)->name
;