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 These macros are used to dispatch to functions through the
94 bfd_target vector. They are used in a number of macros further
95 down in @file{bfd.h}, and are also used when calling various
96 routines by hand inside the BFD implementation. The "arglist"
97 argument must be parenthesized; it contains all the arguments
98 to the called function.
100 They make the documentation (more) unpleasant to read, so if
101 someone wants to fix this and not break the above, please do.
103 .#define BFD_SEND(bfd, message, arglist) \
104 . ((*((bfd)->xvec->message)) arglist)
106 For operations which index on the BFD format
108 .#define BFD_SEND_FMT(bfd, message, arglist) \
109 . (((bfd)->xvec->message[(int)((bfd)->format)]) arglist)
111 This is the struct which defines the type of BFD this is. The
112 <<xvec>> member of the struct <<bfd>> itself points here. Each
113 module that implements access to a different target under BFD,
114 defines one of these.
117 FIXME, these names should be rationalised with the names of
118 the entry points which call them. Too bad we can't have one
119 macro to define them both!
121 .typedef struct bfd_target
124 Identifies the kind of target, eg SunOS4, Ultrix, etc.
128 The "flavour" of a back end is a general indication about the contents
131 . enum target_flavour {
132 . bfd_target_unknown_flavour,
133 . bfd_target_aout_flavour,
134 . bfd_target_coff_flavour,
135 . bfd_target_elf_flavour,
136 . bfd_target_ieee_flavour,
137 . bfd_target_oasys_flavour,
138 . bfd_target_tekhex_flavour,
139 . bfd_target_srec_flavour,
140 . bfd_target_hppa_flavour} flavour;
142 The order of bytes within the data area of a file.
144 . boolean byteorder_big_p;
146 The order of bytes within the header parts of a file.
148 . boolean header_byteorder_big_p;
150 This is a mask of all the flags which an executable may have set -
151 from the set <<NO_FLAGS>>, <<HAS_RELOC>>, ...<<D_PAGED>>.
153 . flagword object_flags;
155 This is a mask of all the flags which a section may have set - from
156 the set <<SEC_NO_FLAGS>>, <<SEC_ALLOC>>, ...<<SET_NEVER_LOAD>>.
158 . flagword section_flags;
160 The character normally found at the front of a symbol
163 . char symbol_leading_char;
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 . bfd_vma (*bfd_getx64) PARAMS ((bfd_byte *));
182 . void (*bfd_putx64) PARAMS ((bfd_vma, bfd_byte *));
183 . bfd_vma (*bfd_getx32) PARAMS ((bfd_byte *));
184 . void (*bfd_putx32) PARAMS ((bfd_vma, bfd_byte *));
185 . bfd_vma (*bfd_getx16) PARAMS ((bfd_byte *));
186 . void (*bfd_putx16) PARAMS ((bfd_vma, bfd_byte *));
188 Byte swapping for the headers
190 . bfd_vma (*bfd_h_getx64) PARAMS ((bfd_byte *));
191 . void (*bfd_h_putx64) PARAMS ((bfd_vma, bfd_byte *));
192 . bfd_vma (*bfd_h_getx32) PARAMS ((bfd_byte *));
193 . void (*bfd_h_putx32) PARAMS ((bfd_vma, bfd_byte *));
194 . bfd_vma (*bfd_h_getx16) PARAMS ((bfd_byte *));
195 . void (*bfd_h_putx16) PARAMS ((bfd_vma, bfd_byte *));
197 Format dependent routines: these are 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 . struct bfd_target * (*_bfd_check_format[bfd_type_end]) PARAMS ((bfd *));
204 Set the format of a file being written.
206 . boolean (*_bfd_set_format[bfd_type_end]) PARAMS ((bfd *));
208 Write cached information into a file being written, at bfd_close.
210 . boolean (*_bfd_write_contents[bfd_type_end]) PARAMS ((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 . char * (*_core_file_failing_command) PARAMS ((bfd *));
220 . int (*_core_file_failing_signal) PARAMS ((bfd *));
221 . boolean (*_core_file_matches_executable_p) PARAMS ((bfd *, bfd *));
225 . boolean (*_bfd_slurp_armap) PARAMS ((bfd *));
226 . boolean (*_bfd_slurp_extended_name_table) PARAMS ((bfd *));
227 . void (*_bfd_truncate_arname) PARAMS ((bfd *, CONST char *, char *));
228 . boolean (*write_armap) PARAMS ((bfd *arch,
229 . unsigned int elength,
231 . unsigned int orl_count,
236 . boolean (*_close_and_cleanup) PARAMS ((bfd *));
237 . boolean (*_bfd_set_section_contents) PARAMS ((bfd *, sec_ptr, PTR,
238 . file_ptr, bfd_size_type));
239 . boolean (*_bfd_get_section_contents) PARAMS ((bfd *, sec_ptr, PTR,
240 . file_ptr, bfd_size_type));
241 . boolean (*_new_section_hook) PARAMS ((bfd *, sec_ptr));
243 Symbols and relocations
245 . unsigned int (*_get_symtab_upper_bound) PARAMS ((bfd *));
246 . unsigned int (*_bfd_canonicalize_symtab) PARAMS ((bfd *,
247 . struct symbol_cache_entry **));
248 . unsigned int (*_get_reloc_upper_bound) PARAMS ((bfd *, sec_ptr));
249 . unsigned int (*_bfd_canonicalize_reloc) PARAMS ((bfd *, sec_ptr, arelent **,
250 . struct symbol_cache_entry **));
251 . struct symbol_cache_entry *
252 . (*_bfd_make_empty_symbol) PARAMS ((bfd *));
253 . void (*_bfd_print_symbol) PARAMS ((bfd *, PTR,
254 . struct symbol_cache_entry *,
255 . bfd_print_symbol_type));
256 .#define bfd_print_symbol(b,p,s,e) BFD_SEND(b, _bfd_print_symbol, (b,p,s,e))
258 . alent * (*_get_lineno) PARAMS ((bfd *, struct symbol_cache_entry *));
260 . boolean (*_bfd_set_arch_mach) PARAMS ((bfd *, enum bfd_architecture,
263 . bfd * (*openr_next_archived_file) PARAMS ((bfd *arch, bfd *prev));
265 . boolean (*_bfd_find_nearest_line) PARAMS ((bfd *abfd,
266 . struct sec *section, struct symbol_cache_entry **symbols,
267 . bfd_vma offset, CONST char **file, CONST char **func,
268 . unsigned int *line));
270 . int (*_bfd_stat_arch_elt) PARAMS ((bfd *, struct stat *));
272 . int (*_bfd_sizeof_headers) PARAMS ((bfd *, boolean));
274 . void (*_bfd_debug_info_start) PARAMS ((bfd *));
275 . void (*_bfd_debug_info_end) PARAMS ((bfd *));
276 . void (*_bfd_debug_info_accumulate) PARAMS ((bfd *, struct sec *));
278 . bfd_byte * (*_bfd_get_relocated_section_contents) PARAMS ((bfd *,
279 . struct bfd_seclet *, bfd_byte *data));
281 . boolean (*_bfd_relax_section) PARAMS ((bfd *, struct sec *,
282 . struct symbol_cache_entry **));
284 . {* See documentation on reloc types. *}
285 . CONST struct reloc_howto_struct *
286 . (*reloc_type_lookup) PARAMS ((bfd *abfd,
287 . bfd_reloc_code_real_type code));
289 . {* Back-door to allow format-aware applications to create debug symbols
290 . while using BFD for everything else. Currently used by the assembler
291 . when creating COFF files. *}
292 . asymbol * (*_bfd_make_debug_symbol) PARAMS ((
295 . unsigned long size));
297 Data for use by back-end routines; e.g., for a.out, includes whether
298 this particular target maps ZMAGIC files contiguously or with text and
299 data separated. Could perhaps also be used to eliminate some of the
300 above COFF-specific fields.
307 /* The default is to define a target_vector containing all the targets.
308 By setting MINIMIZE=1 on the "make" command line, the user can change this
309 to a vector containing just DEFAULT_VECTOR and any required
310 traditional-core-file handler. (This is to save space in the executables.)
311 The config files can also override the default large vector by giving an
312 explicit SELECT_VECS macro. */
314 #if MINIMIZE && defined(DEFAULT_VECTOR) && !defined(SELECT_VECS)
316 #define SELECT_VECS &DEFAULT_VECTOR,&trad_core_vec
319 #define SELECT_VECS &DEFAULT_VECTOR,&sco_core_vec
322 #define SELECT_VECS &DEFAULT_VECTOR,&aix386_core_vec
324 #define SELECT_VECS &DEFAULT_VECTOR
330 /* All known xvecs. They are listed a second time below, since
331 we can't intermix extern's and initializers. */
332 extern bfd_target ecoff_little_vec
;
333 extern bfd_target ecoff_big_vec
;
334 extern bfd_target sunos_big_vec
;
335 extern bfd_target demo_64_vec
;
336 extern bfd_target srec_vec
;
337 extern bfd_target tekhex_vec
;
338 extern bfd_target a_out_adobe_vec
;
339 extern bfd_target b_out_vec_little_host
;
340 extern bfd_target b_out_vec_big_host
;
341 extern bfd_target icoff_little_vec
;
342 extern bfd_target icoff_big_vec
;
343 extern bfd_target elf_little_vec
;
344 extern bfd_target elf_big_vec
;
345 extern bfd_target ieee_vec
;
346 extern bfd_target oasys_vec
;
347 extern bfd_target m88kbcs_vec
;
348 extern bfd_target m68kcoff_vec
;
349 extern bfd_target i386coff_vec
;
350 extern bfd_target i386aout_vec
;
351 extern bfd_target i386linux_vec
;
352 extern bfd_target a29kcoff_big_vec
;
353 extern bfd_target trad_core_vec
;
354 extern bfd_target sco_core_vec
;
355 extern bfd_target aix386_core_vec
;
356 extern bfd_target rs6000coff_vec
;
357 extern bfd_target h8300coff_vec
;
358 extern bfd_target z8kcoff_vec
;
359 extern bfd_target we32kcoff_vec
;
361 extern bfd_target hppa_vec
;
364 #ifdef DEFAULT_VECTOR
365 extern bfd_target DEFAULT_VECTOR
;
370 bfd_target
*target_vector
[] = {
377 bfd_target
*target_vector
[] = {
379 #ifdef DEFAULT_VECTOR
389 /* We have no oasys tools anymore, so we can't test any of this
390 anymore. If you want to test the stuff yourself, go ahead...
392 Worse, since there is no magic number for archives, there
393 can annoying target mis-matches. */
398 &demo_64_vec
, /* Only compiled if host has long-long support */
410 &b_out_vec_little_host
,
429 NULL
, /* end of list marker */
434 /* default_vector[0] contains either the address of the default vector,
435 if there is one, or zero if there isn't. */
437 bfd_target
*default_vector
[] = {
438 #ifdef DEFAULT_VECTOR
452 Returns a pointer to the transfer vector for the object target
453 named target_name. If target_name is NULL, chooses the one in
454 the environment variable GNUTARGET; if that is null or not
455 defined thenthe first entry in the target list is chosen.
456 Passing in the string "default" or setting the environment
457 variable to "default" will cause the first entry in the target
458 list to be returned, and "target_defaulted" will be set in the
459 BFD. This causes <<bfd_check_format>> to loop over all the
460 targets to find the one that matches the file being read.
463 bfd_target *bfd_find_target(CONST char *, bfd *);
467 DEFUN(bfd_find_target
,(target_name
, abfd
),
468 CONST
char *target_name AND
472 extern char *getenv ();
473 CONST
char *targname
= (target_name
? target_name
:
474 (CONST
char *) getenv ("GNUTARGET"));
476 /* This is safe; the vector cannot be null */
477 if (targname
== NULL
|| !strcmp (targname
, "default")) {
478 abfd
->target_defaulted
= true;
479 return abfd
->xvec
= target_vector
[0];
482 abfd
->target_defaulted
= false;
484 for (target
= &target_vector
[0]; *target
!= NULL
; target
++) {
485 if (!strcmp (targname
, (*target
)->name
))
486 return abfd
->xvec
= *target
;
489 bfd_error
= invalid_target
;
499 This function returns a freshly malloced NULL-terminated
500 vector of the names of all the valid BFD targets. Do not
504 CONST char **bfd_target_list(void);
509 DEFUN_VOID(bfd_target_list
)
512 #ifdef NATIVE_HPPAHPUX_COMPILER
513 /* The native compiler on the HP9000/700 has a bug which causes it
514 to loop endlessly when compiling this file. This avoids it. */
518 CONST
char **name_list
, **name_ptr
;
520 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
524 name_list
= (CONST
char **) zalloc ((vec_length
+ 1) * sizeof (char **));
526 if (name_list
== NULL
) {
527 bfd_error
= no_memory
;
531 for (target
= &target_vector
[0]; *target
!= NULL
; target
++)
532 *(name_ptr
++) = (*target
)->name
;