1 /* Generic target-file-type support for the BFD library.
2 Copyright (C) 1990-1991 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. @xref{bfd_target}.
53 o Otherwise, the elements in the target vector are inspected
54 one by one, until a match on target name is found. When found,
57 o Otherwise the error <<invalid_target>> is returned to
60 o <<bfd_openr>> attempts to open the file using
61 <<bfd_open_file>>, and returns the BFD.
63 Once the BFD has been opened and the target selected, the file
64 format may be determined. This is done by calling
65 <<bfd_check_format>> on the BFD with a suggested format. The
66 routine returns <<true>> when the application guesses right.
76 bfd_target, , Targets, Targets
82 This structure contains everything that BFD knows about a
83 target. It includes things like its byte order, name, what
84 routines to call to do various operations, etc.
86 Every BFD points to a target structure with its <<xvec>>
89 Shortcut for declaring fields which are prototyped function
90 pointers, while avoiding anguish on compilers that don't
93 .#define SDEF(ret, name, arglist) \
94 . PROTO(ret,(*name),arglist)
95 .#define SDEF_FMT(ret, name, arglist) \
96 . PROTO(ret,(*name[bfd_type_end]),arglist)
98 These macros are used to dispatch to functions through the
99 bfd_target vector. They are used in a number of macros further
100 down in @file{bfd.h}, and are also used when calling various
101 routines by hand inside the BFD implementation. The "arglist"
102 argument must be parenthesized; it contains all the arguments
103 to the called function.
105 They make the documentation (more) unpleasant to read, so if
106 someone wants to fix this and not break the above, please do.
108 .#define BFD_SEND(bfd, message, arglist) \
109 . ((*((bfd)->xvec->message)) arglist)
111 For operations which index on the BFD format
113 .#define BFD_SEND_FMT(bfd, message, arglist) \
114 . (((bfd)->xvec->message[(int)((bfd)->format)]) arglist)
116 This is the struct which defines the type of BFD this is. The
117 <<xvec>> member of the struct <<bfd>> itself points here. Each
118 module that implements access to a different target under BFD,
119 defines one of these.
122 FIXME, these names should be rationalised with the names of
123 the entry points which call them. Too bad we can't have one
124 macro to define them both!
126 .typedef struct bfd_target
129 Identifies the kind of target, eg SunOS4, Ultrix, etc.
133 The "flavour" of a back end is a general indication about the contents
136 . enum target_flavour {
137 . bfd_target_unknown_flavour,
138 . bfd_target_aout_flavour,
139 . bfd_target_coff_flavour,
140 . bfd_target_elf_flavour,
141 . bfd_target_ieee_flavour,
142 . bfd_target_oasys_flavour,
143 . bfd_target_tekhex_flavour,
144 . bfd_target_srec_flavour,
145 . bfd_target_hppa_flavour} flavour;
147 The order of bytes within the data area of a file.
149 . boolean byteorder_big_p;
151 The order of bytes within the header parts of a file.
153 . boolean header_byteorder_big_p;
155 This is a mask of all the flags which an executable may have set -
156 from the set <<NO_FLAGS>>, <<HAS_RELOC>>, ...<<D_PAGED>>.
158 . flagword object_flags;
160 This is a mask of all the flags which a section may have set - from
161 the set <<SEC_NO_FLAGS>>, <<SEC_ALLOC>>, ...<<SET_NEVER_LOAD>>.
163 . flagword section_flags;
165 The pad character for filenames within an archive header.
169 The maximum number of characters in an archive header.
171 . unsigned short ar_max_namelen;
173 The minimum alignment restriction for any section.
175 . unsigned int align_power_min;
177 Entries for byte swapping for data. These are different to the other
178 entry points, since they don't take BFD as first arg. Certain other handlers
181 . SDEF (bfd_vma, bfd_getx64, (bfd_byte *));
182 . SDEF (void, bfd_putx64, (bfd_vma, bfd_byte *));
183 . SDEF (bfd_vma, bfd_getx32, (bfd_byte *));
184 . SDEF (void, bfd_putx32, (bfd_vma, bfd_byte *));
185 . SDEF (bfd_vma, bfd_getx16, (bfd_byte *));
186 . SDEF (void, bfd_putx16, (bfd_vma, bfd_byte *));
188 Byte swapping for the headers
190 . SDEF (bfd_vma, bfd_h_getx64, (bfd_byte *));
191 . SDEF (void, bfd_h_putx64, (bfd_vma, bfd_byte *));
192 . SDEF (bfd_vma, bfd_h_getx32, (bfd_byte *));
193 . SDEF (void, bfd_h_putx32, (bfd_vma, bfd_byte *));
194 . SDEF (bfd_vma, bfd_h_getx16, (bfd_byte *));
195 . SDEF (void, bfd_h_putx16, (bfd_vma, bfd_byte *));
197 Format dependent routines, these turn into vectors of entry points
198 within the target vector structure; one for each format to check.
200 Check the format of a file being read. Return bfd_target * or zero.
202 . SDEF_FMT (struct bfd_target *, _bfd_check_format, (bfd *));
204 Set the format of a file being written.
206 . SDEF_FMT (boolean, _bfd_set_format, (bfd *));
208 Write cached information into a file being written, at bfd_close.
210 . SDEF_FMT (boolean, _bfd_write_contents, (bfd *));
212 The following functions are defined in <<JUMP_TABLE>>. The idea is
213 that the back end writer of <<foo>> names all the routines
214 <<foo_>>@var{entry_point}, <<JUMP_TABLE>> will built the entries
215 in this structure in the right order.
217 Core file entry points
219 . SDEF (char *, _core_file_failing_command, (bfd *));
220 . SDEF (int, _core_file_failing_signal, (bfd *));
221 . SDEF (boolean, _core_file_matches_executable_p, (bfd *, bfd *));
225 . SDEF (boolean, _bfd_slurp_armap, (bfd *));
226 . SDEF (boolean, _bfd_slurp_extended_name_table, (bfd *));
227 . SDEF (void, _bfd_truncate_arname, (bfd *, CONST char *, char *));
228 . SDEF (boolean, write_armap, (bfd *arch,
229 . unsigned int elength,
231 . unsigned int orl_count,
236 . SDEF (boolean, _close_and_cleanup, (bfd *));
237 . SDEF (boolean, _bfd_set_section_contents, (bfd *, sec_ptr, PTR,
238 . file_ptr, bfd_size_type));
239 . SDEF (boolean, _bfd_get_section_contents, (bfd *, sec_ptr, PTR,
240 . file_ptr, bfd_size_type));
241 . SDEF (boolean, _new_section_hook, (bfd *, sec_ptr));
243 Symbols and relocations
245 . SDEF (unsigned int, _get_symtab_upper_bound, (bfd *));
246 . SDEF (unsigned int, _bfd_canonicalize_symtab,
247 . (bfd *, struct symbol_cache_entry **));
248 . SDEF (unsigned int, _get_reloc_upper_bound, (bfd *, sec_ptr));
249 . SDEF (unsigned int, _bfd_canonicalize_reloc, (bfd *, sec_ptr, arelent **,
250 . struct symbol_cache_entry**));
251 . SDEF (struct symbol_cache_entry *, _bfd_make_empty_symbol, (bfd *));
252 . SDEF (void, _bfd_print_symbol, (bfd *, PTR, struct symbol_cache_entry *,
253 . bfd_print_symbol_type));
254 .#define bfd_print_symbol(b,p,s,e) BFD_SEND(b, _bfd_print_symbol, (b,p,s,e))
255 . SDEF (alent *, _get_lineno, (bfd *, struct symbol_cache_entry *));
257 . SDEF (boolean, _bfd_set_arch_mach, (bfd *, enum bfd_architecture,
260 . SDEF (bfd *, openr_next_archived_file, (bfd *arch, bfd *prev));
261 . SDEF (boolean, _bfd_find_nearest_line,
262 . (bfd *abfd, struct sec *section,
263 . struct symbol_cache_entry **symbols,bfd_vma offset,
264 . CONST char **file, CONST char **func, unsigned int *line));
265 . SDEF (int, _bfd_stat_arch_elt, (bfd *, struct stat *));
267 . SDEF (int, _bfd_sizeof_headers, (bfd *, boolean));
269 . SDEF (void, _bfd_debug_info_start, (bfd *));
270 . SDEF (void, _bfd_debug_info_end, (bfd *));
271 . SDEF (void, _bfd_debug_info_accumulate, (bfd *, struct sec *));
272 . SDEF (bfd_byte *, _bfd_get_relocated_section_contents, (bfd*,struct bfd_seclet_struct *, bfd_byte *data));
273 . SDEF (boolean,_bfd_relax_section,(bfd *, struct sec *, struct symbol_cache_entry **));
274 Special entry points for gdb to swap in coff symbol table parts
276 . SDEF(void, _bfd_coff_swap_aux_in,(
283 . SDEF(void, _bfd_coff_swap_sym_in,(
288 . SDEF(void, _bfd_coff_swap_lineno_in, (
294 Special entry points for gas to swap coff parts
296 . SDEF(unsigned int, _bfd_coff_swap_aux_out,(
303 . SDEF(unsigned int, _bfd_coff_swap_sym_out,(
308 . SDEF(unsigned int, _bfd_coff_swap_lineno_out,(
313 . SDEF(unsigned int, _bfd_coff_swap_reloc_out,(
318 . SDEF(unsigned int, _bfd_coff_swap_filehdr_out,(
323 . SDEF(unsigned int, _bfd_coff_swap_aouthdr_out,(
328 . SDEF(unsigned int, _bfd_coff_swap_scnhdr_out,(
333 . {* See documentation on reloc types. *}
334 . SDEF (CONST struct reloc_howto_struct *,
336 . (bfd *abfd, bfd_reloc_code_real_type code));
338 . {* Complete and utter crock, currently used for the assembler
339 . when creating COFF files. *}
340 . SDEF (asymbol *, _bfd_make_debug_symbol, (
343 . unsigned long size));
345 Data for use by back-end routines; e.g., for a.out, includes whether
346 this particular target maps ZMAGIC files contiguously or with text and
347 data separated. Could perhaps also be used to eliminate some of the
348 above COFF-specific fields.
355 /* The default is to define a target_vector containing all the targets.
356 By setting MINIMIZE=1 on the "make" command line, the user can change this
357 to a vector containing just DEFAULT_VECTOR and any required
358 traditional-core-file handler. (This is to save space in the executables.)
359 The config files can also override the default large vector by giving an
360 explicit SELECT_VECS macro. */
362 #if MINIMIZE && defined(DEFAULT_VECTOR) && !defined(SELECT_VECS)
364 #define SELECT_VECS &DEFAULT_VECTOR,&trad_core_vec
366 #define SELECT_VECS &DEFAULT_VECTOR
370 /* All known xvecs. They are listed a second time below, since
371 we can't intermix extern's and initializers. */
372 extern bfd_target ecoff_little_vec
;
373 extern bfd_target ecoff_big_vec
;
374 extern bfd_target sunos_big_vec
;
375 extern bfd_target demo_64_vec
;
376 extern bfd_target srec_vec
;
377 extern bfd_target tekhex_vec
;
378 extern bfd_target b_out_vec_little_host
;
379 extern bfd_target b_out_vec_big_host
;
380 extern bfd_target icoff_little_vec
;
381 extern bfd_target icoff_big_vec
;
382 extern bfd_target elf_little_vec
;
383 extern bfd_target elf_big_vec
;
384 extern bfd_target ieee_vec
;
385 extern bfd_target oasys_vec
;
386 extern bfd_target m88kbcs_vec
;
387 extern bfd_target m68kcoff_vec
;
388 extern bfd_target i386coff_vec
;
389 extern bfd_target i386aout_vec
;
390 extern bfd_target i386linux_vec
;
391 extern bfd_target a29kcoff_big_vec
;
392 extern bfd_target trad_core_vec
;
393 extern bfd_target rs6000coff_vec
;
394 extern bfd_target h8300coff_vec
;
395 extern bfd_target z8kcoff_vec
;
396 extern bfd_target we32kcoff_vec
;
398 extern bfd_target hppa_vec
;
401 #ifdef DEFAULT_VECTOR
402 extern bfd_target DEFAULT_VECTOR
;
407 bfd_target
*target_vector
[] = {
414 bfd_target
*target_vector
[] = {
416 #ifdef DEFAULT_VECTOR
426 /* We have no oasys tools anymore, so we can't test any of this
427 anymore. If you want to test the stuff yourself, go ahead...
433 &demo_64_vec
, /* Only compiled if host has long-long support */
444 &b_out_vec_little_host
,
457 NULL
, /* end of list marker */
462 /* default_vector[0] contains either the address of the default vector,
463 if there is one, or zero if there isn't. */
465 bfd_target
*default_vector
[] = {
466 #ifdef DEFAULT_VECTOR
480 Returns a pointer to the transfer vector for the object target
481 named target_name. If target_name is NULL, chooses the one in
482 the environment variable GNUTARGET; if that is null or not
483 defined thenthe first entry in the target list is chosen.
484 Passing in the string "default" or setting the environment
485 variable to "default" will cause the first entry in the target
486 list to be returned, and "target_defaulted" will be set in the
487 BFD. This causes <<bfd_check_format>> to loop over all the
488 targets to find the one that matches the file being read.
491 bfd_target *bfd_find_target(CONST char *, bfd *);
495 DEFUN(bfd_find_target
,(target_name
, abfd
),
496 CONST
char *target_name AND
500 extern char *getenv ();
501 CONST
char *targname
= (target_name
? target_name
:
502 (CONST
char *) getenv ("GNUTARGET"));
504 /* This is safe; the vector cannot be null */
505 if (targname
== NULL
|| !strcmp (targname
, "default")) {
506 abfd
->target_defaulted
= true;
507 return abfd
->xvec
= target_vector
[0];
510 abfd
->target_defaulted
= false;
512 for (target
= &target_vector
[0]; *target
!= NULL
; target
++) {
513 if (!strcmp (targname
, (*target
)->name
))
514 return abfd
->xvec
= *target
;
517 bfd_error
= invalid_target
;
527 This function returns a freshly malloced NULL-terminated
528 vector of the names of all the valid BFD targets. Do not
532 CONST char **bfd_target_list(void);
537 DEFUN_VOID(bfd_target_list
)
541 CONST
char **name_list
, **name_ptr
;
543 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
547 name_list
= (CONST
char **) zalloc ((vec_length
+ 1) * sizeof (char **));
549 if (name_list
== NULL
) {
550 bfd_error
= no_memory
;
554 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
555 *(name_ptr
++) = (*target
)->name
;