1 @section @code{typedef bfd}
2 A BFD has type @code{bfd}; objects of this type are the
3 cornerstone of any application using BFD. Using BFD
4 consists of making references though the BFD and to data in the BFD.
6 Here is the structure that defines the type @code{bfd}. It
7 contains the major data about the file and pointers
8 to the rest of the data.
15 /* The filename the application opened the BFD with. */
18 /* A pointer to the target jump table. */
19 const struct bfd_target *xvec;
21 /* To avoid dragging too many header files into every file that
22 includes `@code{bfd.h}', IOSTREAM has been declared as a "char
23 *", and MTIME as a "long". Their correct types, to which they
24 are cast when used, are "FILE *" and "time_t". The iostream
25 is the result of an fopen on the filename. However, if the
26 BFD_IN_MEMORY flag is set, then iostream is actually a pointer
27 to a bfd_in_memory struct. */
30 /* Is the file descriptor being cached? That is, can it be closed as
31 needed, and re-opened when accessed later? */
35 /* Marks whether there was a default target specified when the
36 BFD was opened. This is used to select which matching algorithm
37 to use to choose the back end. */
39 boolean target_defaulted;
41 /* The caching routines use these to maintain a
42 least-recently-used list of BFDs */
44 struct _bfd *lru_prev, *lru_next;
46 /* When a file is closed by the caching routines, BFD retains
47 state information on the file here: */
51 /* and here: (``once'' means at least once) */
55 /* Set if we have a locally maintained mtime value, rather than
56 getting it from the file each time: */
60 /* File modified time, if mtime_set is true: */
64 /* Reserved for an unimplemented file locking extension.*/
68 /* The format which belongs to the BFD. (object, core, etc.) */
72 /* The direction the BFD was opened with*/
74 enum bfd_direction @{no_direction = 0,
77 both_direction = 3@} direction;
79 /* Format_specific flags*/
83 /* Currently my_archive is tested before adding origin to
84 anything. I believe that this can become always an add of
85 origin, with origin set to 0 for non archive files. */
89 /* Remember when output has begun, to stop strange things
91 boolean output_has_begun;
93 /* Pointer to linked list of sections*/
96 /* The number of sections */
97 unsigned int section_count;
99 /* Stuff only useful for object files:
100 The start address. */
101 bfd_vma start_address;
103 /* Used for input and output*/
104 unsigned int symcount;
106 /* Symbol table for output BFD (with symcount entries) */
107 struct symbol_cache_entry **outsymbols;
109 /* Pointer to structure which contains architecture information*/
110 const struct bfd_arch_info *arch_info;
112 /* Stuff only useful for archives:*/
114 struct _bfd *my_archive; /* The containing archive BFD. */
115 struct _bfd *next; /* The next BFD in the archive. */
116 struct _bfd *archive_head; /* The first BFD in the archive. */
119 /* A chain of BFD structures involved in a link. */
120 struct _bfd *link_next;
122 /* A field used by _bfd_generic_link_add_archive_symbols. This will
123 be used only for archive elements. */
126 /* Used by the back end to hold private data. */
130 struct aout_data_struct *aout_data;
131 struct artdata *aout_ar_data;
132 struct _oasys_data *oasys_obj_data;
133 struct _oasys_ar_data *oasys_ar_data;
134 struct coff_tdata *coff_obj_data;
135 struct pe_tdata *pe_obj_data;
136 struct xcoff_tdata *xcoff_obj_data;
137 struct ecoff_tdata *ecoff_obj_data;
138 struct ieee_data_struct *ieee_data;
139 struct ieee_ar_data_struct *ieee_ar_data;
140 struct srec_data_struct *srec_data;
141 struct ihex_data_struct *ihex_data;
142 struct tekhex_data_struct *tekhex_data;
143 struct elf_obj_tdata *elf_obj_data;
144 struct nlm_obj_tdata *nlm_obj_data;
145 struct bout_data_struct *bout_data;
146 struct sun_core_struct *sun_core_data;
147 struct trad_core_struct *trad_core_data;
148 struct som_data_struct *som_data;
149 struct hpux_core_struct *hpux_core_data;
150 struct hppabsd_core_struct *hppabsd_core_data;
151 struct sgi_core_struct *sgi_core_data;
152 struct lynx_core_struct *lynx_core_data;
153 struct osf_core_struct *osf_core_data;
154 struct cisco_core_struct *cisco_core_data;
155 struct versados_data_struct *versados_data;
156 struct netbsd_core_struct *netbsd_core_data;
160 /* Used by the application to hold private data*/
163 /* Where all the allocated stuff under this BFD goes. This is a
164 struct objalloc *, but we use PTR to avoid requiring the inclusion of
170 @section Error reporting
171 Most BFD functions return nonzero on success (check their
172 individual documentation for precise semantics). On an error,
173 they call @code{bfd_set_error} to set an error condition that callers
174 can check by calling @code{bfd_get_error}.
175 If that returns @code{bfd_error_system_call}, then check
178 The easiest way to report a BFD error to the user is to
179 use @code{bfd_perror}.
181 @subsection Type @code{bfd_error_type}
182 The values returned by @code{bfd_get_error} are defined by the
183 enumerated type @code{bfd_error_type}.
188 typedef enum bfd_error
190 bfd_error_no_error = 0,
191 bfd_error_system_call,
192 bfd_error_invalid_target,
193 bfd_error_wrong_format,
194 bfd_error_invalid_operation,
196 bfd_error_no_symbols,
198 bfd_error_no_more_archived_files,
199 bfd_error_malformed_archive,
200 bfd_error_file_not_recognized,
201 bfd_error_file_ambiguously_recognized,
202 bfd_error_no_contents,
203 bfd_error_nonrepresentable_section,
204 bfd_error_no_debug_section,
206 bfd_error_file_truncated,
207 bfd_error_file_too_big,
208 bfd_error_invalid_error_code
212 @findex bfd_get_error
213 @subsubsection @code{bfd_get_error}
216 bfd_error_type bfd_get_error (void);
218 @strong{Description}@*
219 Return the current BFD error condition.
221 @findex bfd_set_error
222 @subsubsection @code{bfd_set_error}
225 void bfd_set_error (bfd_error_type error_tag);
227 @strong{Description}@*
228 Set the BFD error condition to be @var{error_tag}.
231 @subsubsection @code{bfd_errmsg}
234 CONST char *bfd_errmsg (bfd_error_type error_tag);
236 @strong{Description}@*
237 Return a string describing the error @var{error_tag}, or
238 the system error if @var{error_tag} is @code{bfd_error_system_call}.
241 @subsubsection @code{bfd_perror}
244 void bfd_perror (CONST char *message);
246 @strong{Description}@*
247 Print to the standard error stream a string describing the
248 last BFD error that occurred, or the last system error if
249 the last BFD error was a system call failure. If @var{message}
250 is non-NULL and non-empty, the error string printed is preceded
251 by @var{message}, a colon, and a space. It is followed by a newline.
253 @subsection BFD error handler
254 Some BFD functions want to print messages describing the
255 problem. They call a BFD error handler function. This
256 function may be overriden by the program.
258 The BFD error handler acts like printf.
263 typedef void (*bfd_error_handler_type) PARAMS ((const char *, ...));
266 @findex bfd_set_error_handler
267 @subsubsection @code{bfd_set_error_handler}
270 bfd_error_handler_type bfd_set_error_handler (bfd_error_handler_type);
272 @strong{Description}@*
273 Set the BFD error handler function. Returns the previous
276 @findex bfd_set_error_program_name
277 @subsubsection @code{bfd_set_error_program_name}
280 void bfd_set_error_program_name (const char *);
282 @strong{Description}@*
283 Set the program name to use when printing a BFD error. This
284 is printed before the error message followed by a colon and
285 space. The string must not be changed after it is passed to
288 @findex bfd_get_error_handler
289 @subsubsection @code{bfd_get_error_handler}
292 bfd_error_handler_type bfd_get_error_handler (void);
294 @strong{Description}@*
295 Return the BFD error handler function.
300 @findex bfd_get_reloc_upper_bound
301 @subsubsection @code{bfd_get_reloc_upper_bound}
304 long bfd_get_reloc_upper_bound(bfd *abfd, asection *sect);
306 @strong{Description}@*
307 Return the number of bytes required to store the
308 relocation information associated with section @var{sect}
309 attached to bfd @var{abfd}. If an error occurs, return -1.
311 @findex bfd_canonicalize_reloc
312 @subsubsection @code{bfd_canonicalize_reloc}
315 long bfd_canonicalize_reloc
321 @strong{Description}@*
322 Call the back end associated with the open BFD
323 @var{abfd} and translate the external form of the relocation
324 information attached to @var{sec} into the internal canonical
325 form. Place the table into memory at @var{loc}, which has
326 been preallocated, usually by a call to
327 @code{bfd_get_reloc_upper_bound}. Returns the number of relocs, or
330 The @var{syms} table is also needed for horrible internal magic
333 @findex bfd_set_reloc
334 @subsubsection @code{bfd_set_reloc}
338 (bfd *abfd, asection *sec, arelent **rel, unsigned int count)
340 @strong{Description}@*
341 Set the relocation pointer and count within
342 section @var{sec} to the values @var{rel} and @var{count}.
343 The argument @var{abfd} is ignored.
345 @findex bfd_set_file_flags
346 @subsubsection @code{bfd_set_file_flags}
349 boolean bfd_set_file_flags(bfd *abfd, flagword flags);
351 @strong{Description}@*
352 Set the flag word in the BFD @var{abfd} to the value @var{flags}.
358 @code{bfd_error_wrong_format} - The target bfd was not of object format.
360 @code{bfd_error_invalid_operation} - The target bfd was open for reading.
362 @code{bfd_error_invalid_operation} -
363 The flag word contained a bit which was not applicable to the
364 type of file. E.g., an attempt was made to set the @code{D_PAGED} bit
365 on a BFD format which does not support demand paging.
368 @findex bfd_set_start_address
369 @subsubsection @code{bfd_set_start_address}
372 boolean bfd_set_start_address(bfd *abfd, bfd_vma vma);
374 @strong{Description}@*
375 Make @var{vma} the entry point of output BFD @var{abfd}.
378 Returns @code{true} on success, @code{false} otherwise.
380 @findex bfd_get_mtime
381 @subsubsection @code{bfd_get_mtime}
384 long bfd_get_mtime(bfd *abfd);
386 @strong{Description}@*
387 Return the file modification time (as read from the file system, or
388 from the archive header for archive members).
391 @subsubsection @code{bfd_get_size}
394 long bfd_get_size(bfd *abfd);
396 @strong{Description}@*
397 Return the file size (as read from file system) for the file
398 associated with BFD @var{abfd}.
400 The initial motivation for, and use of, this routine is not
401 so we can get the exact size of the object the BFD applies to, since
402 that might not be generally possible (archive members for example).
403 It would be ideal if someone could eventually modify
404 it so that such results were guaranteed.
406 Instead, we want to ask questions like "is this NNN byte sized
407 object I'm about to try read from file offset YYY reasonable?"
408 As as example of where we might do this, some object formats
409 use string tables for which the first @code{sizeof(long)} bytes of the
410 table contain the size of the table itself, including the size bytes.
411 If an application tries to read what it thinks is one of these
412 string tables, without some way to validate the size, and for
413 some reason the size is wrong (byte swapping error, wrong location
414 for the string table, etc.), the only clue is likely to be a read
415 error when it tries to read the table, or a "virtual memory
416 exhausted" error when it tries to allocate 15 bazillon bytes
417 of space for the 15 bazillon byte table it is about to read.
418 This function at least allows us to answer the quesion, "is the
421 @findex bfd_get_gp_size
422 @subsubsection @code{bfd_get_gp_size}
425 int bfd_get_gp_size(bfd *abfd);
427 @strong{Description}@*
428 Return the maximum size of objects to be optimized using the GP
429 register under MIPS ECOFF. This is typically set by the @code{-G}
430 argument to the compiler, assembler or linker.
432 @findex bfd_set_gp_size
433 @subsubsection @code{bfd_set_gp_size}
436 void bfd_set_gp_size(bfd *abfd, int i);
438 @strong{Description}@*
439 Set the maximum size of objects to be optimized using the GP
440 register under ECOFF or MIPS ELF. This is typically set by
441 the @code{-G} argument to the compiler, assembler or linker.
444 @subsubsection @code{bfd_scan_vma}
447 bfd_vma bfd_scan_vma(CONST char *string, CONST char **end, int base);
449 @strong{Description}@*
450 Convert, like @code{strtoul}, a numerical expression
451 @var{string} into a @code{bfd_vma} integer, and return that integer.
452 (Though without as many bells and whistles as @code{strtoul}.)
453 The expression is assumed to be unsigned (i.e., positive).
454 If given a @var{base}, it is used as the base for conversion.
455 A base of 0 causes the function to interpret the string
456 in hex if a leading "0x" or "0X" is found, otherwise
457 in octal if a leading zero is found, otherwise in decimal.
459 Overflow is not detected.
461 @findex bfd_copy_private_bfd_data
462 @subsubsection @code{bfd_copy_private_bfd_data}
465 boolean bfd_copy_private_bfd_data(bfd *ibfd, bfd *obfd);
467 @strong{Description}@*
468 Copy private BFD information from the BFD @var{ibfd} to the
469 the BFD @var{obfd}. Return @code{true} on success, @code{false} on error.
470 Possible error returns are:
475 @code{bfd_error_no_memory} -
476 Not enough memory exists to create private data for @var{obfd}.
479 #define bfd_copy_private_bfd_data(ibfd, obfd) \
480 BFD_SEND (obfd, _bfd_copy_private_bfd_data, \
484 @findex bfd_merge_private_bfd_data
485 @subsubsection @code{bfd_merge_private_bfd_data}
488 boolean bfd_merge_private_bfd_data(bfd *ibfd, bfd *obfd);
490 @strong{Description}@*
491 Merge private BFD information from the BFD @var{ibfd} to the
492 the output file BFD @var{obfd} when linking. Return @code{true}
493 on success, @code{false} on error. Possible error returns are:
498 @code{bfd_error_no_memory} -
499 Not enough memory exists to create private data for @var{obfd}.
502 #define bfd_merge_private_bfd_data(ibfd, obfd) \
503 BFD_SEND (obfd, _bfd_merge_private_bfd_data, \
507 @findex bfd_set_private_flags
508 @subsubsection @code{bfd_set_private_flags}
511 boolean bfd_set_private_flags(bfd *abfd, flagword flags);
513 @strong{Description}@*
514 Set private BFD flag information in the BFD @var{abfd}.
515 Return @code{true} on success, @code{false} on error. Possible error
521 @code{bfd_error_no_memory} -
522 Not enough memory exists to create private data for @var{obfd}.
525 #define bfd_set_private_flags(abfd, flags) \
526 BFD_SEND (abfd, _bfd_set_private_flags, \
531 @subsubsection @code{stuff}
532 @strong{Description}@*
533 Stuff which should be documented:
535 #define bfd_sizeof_headers(abfd, reloc) \
536 BFD_SEND (abfd, _bfd_sizeof_headers, (abfd, reloc))
538 #define bfd_find_nearest_line(abfd, sec, syms, off, file, func, line) \
539 BFD_SEND (abfd, _bfd_find_nearest_line, (abfd, sec, syms, off, file, func, line))
541 /* Do these three do anything useful at all, for any back end? */
542 #define bfd_debug_info_start(abfd) \
543 BFD_SEND (abfd, _bfd_debug_info_start, (abfd))
545 #define bfd_debug_info_end(abfd) \
546 BFD_SEND (abfd, _bfd_debug_info_end, (abfd))
548 #define bfd_debug_info_accumulate(abfd, section) \
549 BFD_SEND (abfd, _bfd_debug_info_accumulate, (abfd, section))
552 #define bfd_stat_arch_elt(abfd, stat) \
553 BFD_SEND (abfd, _bfd_stat_arch_elt,(abfd, stat))
555 #define bfd_update_armap_timestamp(abfd) \
556 BFD_SEND (abfd, _bfd_update_armap_timestamp, (abfd))
558 #define bfd_set_arch_mach(abfd, arch, mach)\
559 BFD_SEND ( abfd, _bfd_set_arch_mach, (abfd, arch, mach))
561 #define bfd_relax_section(abfd, section, link_info, again) \
562 BFD_SEND (abfd, _bfd_relax_section, (abfd, section, link_info, again))
564 #define bfd_link_hash_table_create(abfd) \
565 BFD_SEND (abfd, _bfd_link_hash_table_create, (abfd))
567 #define bfd_link_add_symbols(abfd, info) \
568 BFD_SEND (abfd, _bfd_link_add_symbols, (abfd, info))
570 #define bfd_final_link(abfd, info) \
571 BFD_SEND (abfd, _bfd_final_link, (abfd, info))
573 #define bfd_free_cached_info(abfd) \
574 BFD_SEND (abfd, _bfd_free_cached_info, (abfd))
576 #define bfd_get_dynamic_symtab_upper_bound(abfd) \
577 BFD_SEND (abfd, _bfd_get_dynamic_symtab_upper_bound, (abfd))
579 #define bfd_print_private_bfd_data(abfd, file)\
580 BFD_SEND (abfd, _bfd_print_private_bfd_data, (abfd, file))
582 #define bfd_canonicalize_dynamic_symtab(abfd, asymbols) \
583 BFD_SEND (abfd, _bfd_canonicalize_dynamic_symtab, (abfd, asymbols))
585 #define bfd_get_dynamic_reloc_upper_bound(abfd) \
586 BFD_SEND (abfd, _bfd_get_dynamic_reloc_upper_bound, (abfd))
588 #define bfd_canonicalize_dynamic_reloc(abfd, arels, asyms) \
589 BFD_SEND (abfd, _bfd_canonicalize_dynamic_reloc, (abfd, arels, asyms))
591 extern bfd_byte *bfd_get_relocated_section_contents
592 PARAMS ((bfd *, struct bfd_link_info *,
593 struct bfd_link_order *, bfd_byte *,
594 boolean, asymbol **));