1 /* Object file "section" support for the BFD library.
2    Copyright (C) 1990-2016 Free Software Foundation, Inc.
3    Written by Cygnus Support.
4 
5    This file is part of BFD, the Binary File Descriptor library.
6 
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 3 of the License, or
10    (at your option) any later version.
11 
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.
16 
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., 51 Franklin Street - Fifth Floor, Boston,
20    MA 02110-1301, USA.  */
21 
22 /*
23 SECTION
24 	Sections
25 
26 	The raw data contained within a BFD is maintained through the
27 	section abstraction.  A single BFD may have any number of
28 	sections.  It keeps hold of them by pointing to the first;
29 	each one points to the next in the list.
30 
31 	Sections are supported in BFD in <<section.c>>.
32 
33 @menu
34 @* Section Input::
35 @* Section Output::
36 @* typedef asection::
37 @* section prototypes::
38 @end menu
39 
40 INODE
41 Section Input, Section Output, Sections, Sections
42 SUBSECTION
43 	Section input
44 
45 	When a BFD is opened for reading, the section structures are
46 	created and attached to the BFD.
47 
48 	Each section has a name which describes the section in the
49 	outside world---for example, <<a.out>> would contain at least
50 	three sections, called <<.text>>, <<.data>> and <<.bss>>.
51 
52 	Names need not be unique; for example a COFF file may have several
53 	sections named <<.data>>.
54 
55 	Sometimes a BFD will contain more than the ``natural'' number of
56 	sections. A back end may attach other sections containing
57 	constructor data, or an application may add a section (using
58 	<<bfd_make_section>>) to the sections attached to an already open
59 	BFD. For example, the linker creates an extra section
60 	<<COMMON>> for each input file's BFD to hold information about
61 	common storage.
62 
63 	The raw data is not necessarily read in when
64 	the section descriptor is created. Some targets may leave the
65 	data in place until a <<bfd_get_section_contents>> call is
66 	made. Other back ends may read in all the data at once.  For
67 	example, an S-record file has to be read once to determine the
68 	size of the data. An IEEE-695 file doesn't contain raw data in
69 	sections, but data and relocation expressions intermixed, so
70 	the data area has to be parsed to get out the data and
71 	relocations.
72 
73 INODE
74 Section Output, typedef asection, Section Input, Sections
75 
76 SUBSECTION
77 	Section output
78 
79 	To write a new object style BFD, the various sections to be
80 	written have to be created. They are attached to the BFD in
81 	the same way as input sections; data is written to the
82 	sections using <<bfd_set_section_contents>>.
83 
84 	Any program that creates or combines sections (e.g., the assembler
85 	and linker) must use the <<asection>> fields <<output_section>> and
86 	<<output_offset>> to indicate the file sections to which each
87 	section must be written.  (If the section is being created from
88 	scratch, <<output_section>> should probably point to the section
89 	itself and <<output_offset>> should probably be zero.)
90 
91 	The data to be written comes from input sections attached
92 	(via <<output_section>> pointers) to
93 	the output sections.  The output section structure can be
94 	considered a filter for the input section: the output section
95 	determines the vma of the output data and the name, but the
96 	input section determines the offset into the output section of
97 	the data to be written.
98 
99 	E.g., to create a section "O", starting at 0x100, 0x123 long,
100 	containing two subsections, "A" at offset 0x0 (i.e., at vma
101 	0x100) and "B" at offset 0x20 (i.e., at vma 0x120) the <<asection>>
102 	structures would look like:
103 
104 |   section name          "A"
105 |     output_offset   0x00
106 |     size            0x20
107 |     output_section ----------->  section name    "O"
108 |                             |    vma             0x100
109 |   section name          "B" |    size            0x123
110 |     output_offset   0x20    |
111 |     size            0x103   |
112 |     output_section  --------|
113 
114 SUBSECTION
115 	Link orders
116 
117 	The data within a section is stored in a @dfn{link_order}.
118 	These are much like the fixups in <<gas>>.  The link_order
119 	abstraction allows a section to grow and shrink within itself.
120 
121 	A link_order knows how big it is, and which is the next
122 	link_order and where the raw data for it is; it also points to
123 	a list of relocations which apply to it.
124 
125 	The link_order is used by the linker to perform relaxing on
126 	final code.  The compiler creates code which is as big as
127 	necessary to make it work without relaxing, and the user can
128 	select whether to relax.  Sometimes relaxing takes a lot of
129 	time.  The linker runs around the relocations to see if any
130 	are attached to data which can be shrunk, if so it does it on
131 	a link_order by link_order basis.
132 
133 */
134 
135 #include "sysdep.h"
136 #include "bfd.h"
137 #include "libbfd.h"
138 #include "bfdlink.h"
139 
140 /*
141 DOCDD
142 INODE
143 typedef asection, section prototypes, Section Output, Sections
144 SUBSECTION
145 	typedef asection
146 
147 	Here is the section structure:
148 
149 CODE_FRAGMENT
150 .
151 .typedef struct bfd_section
152 .{
153 .  {* The name of the section; the name isn't a copy, the pointer is
154 .     the same as that passed to bfd_make_section.  *}
155 .  const char *name;
156 .
157 .  {* A unique sequence number.  *}
158 .  unsigned int id;
159 .
160 .  {* Which section in the bfd; 0..n-1 as sections are created in a bfd.  *}
161 .  unsigned int index;
162 .
163 .  {* The next section in the list belonging to the BFD, or NULL.  *}
164 .  struct bfd_section *next;
165 .
166 .  {* The previous section in the list belonging to the BFD, or NULL.  *}
167 .  struct bfd_section *prev;
168 .
169 .  {* The field flags contains attributes of the section. Some
170 .     flags are read in from the object file, and some are
171 .     synthesized from other information.  *}
172 .  flagword flags;
173 .
174 .#define SEC_NO_FLAGS   0x000
175 .
176 .  {* Tells the OS to allocate space for this section when loading.
177 .     This is clear for a section containing debug information only.  *}
178 .#define SEC_ALLOC      0x001
179 .
180 .  {* Tells the OS to load the section from the file when loading.
181 .     This is clear for a .bss section.  *}
182 .#define SEC_LOAD       0x002
183 .
184 .  {* The section contains data still to be relocated, so there is
185 .     some relocation information too.  *}
186 .#define SEC_RELOC      0x004
187 .
188 .  {* A signal to the OS that the section contains read only data.  *}
189 .#define SEC_READONLY   0x008
190 .
191 .  {* The section contains code only.  *}
192 .#define SEC_CODE       0x010
193 .
194 .  {* The section contains data only.  *}
195 .#define SEC_DATA       0x020
196 .
197 .  {* The section will reside in ROM.  *}
198 .#define SEC_ROM        0x040
199 .
200 .  {* The section contains constructor information. This section
201 .     type is used by the linker to create lists of constructors and
202 .     destructors used by <<g++>>. When a back end sees a symbol
203 .     which should be used in a constructor list, it creates a new
204 .     section for the type of name (e.g., <<__CTOR_LIST__>>), attaches
205 .     the symbol to it, and builds a relocation. To build the lists
206 .     of constructors, all the linker has to do is catenate all the
207 .     sections called <<__CTOR_LIST__>> and relocate the data
208 .     contained within - exactly the operations it would peform on
209 .     standard data.  *}
210 .#define SEC_CONSTRUCTOR 0x080
211 .
212 .  {* The section has contents - a data section could be
213 .     <<SEC_ALLOC>> | <<SEC_HAS_CONTENTS>>; a debug section could be
214 .     <<SEC_HAS_CONTENTS>>  *}
215 .#define SEC_HAS_CONTENTS 0x100
216 .
217 .  {* An instruction to the linker to not output the section
218 .     even if it has information which would normally be written.  *}
219 .#define SEC_NEVER_LOAD 0x200
220 .
221 .  {* The section contains thread local data.  *}
222 .#define SEC_THREAD_LOCAL 0x400
223 .
224 .  {* The section has GOT references.  This flag is only for the
225 .     linker, and is currently only used by the elf32-hppa back end.
226 .     It will be set if global offset table references were detected
227 .     in this section, which indicate to the linker that the section
228 .     contains PIC code, and must be handled specially when doing a
229 .     static link.  *}
230 .#define SEC_HAS_GOT_REF 0x800
231 .
232 .  {* The section contains common symbols (symbols may be defined
233 .     multiple times, the value of a symbol is the amount of
234 .     space it requires, and the largest symbol value is the one
235 .     used).  Most targets have exactly one of these (which we
236 .     translate to bfd_com_section_ptr), but ECOFF has two.  *}
237 .#define SEC_IS_COMMON 0x1000
238 .
239 .  {* The section contains only debugging information.  For
240 .     example, this is set for ELF .debug and .stab sections.
241 .     strip tests this flag to see if a section can be
242 .     discarded.  *}
243 .#define SEC_DEBUGGING 0x2000
244 .
245 .  {* The contents of this section are held in memory pointed to
246 .     by the contents field.  This is checked by bfd_get_section_contents,
247 .     and the data is retrieved from memory if appropriate.  *}
248 .#define SEC_IN_MEMORY 0x4000
249 .
250 .  {* The contents of this section are to be excluded by the
251 .     linker for executable and shared objects unless those
252 .     objects are to be further relocated.  *}
253 .#define SEC_EXCLUDE 0x8000
254 .
255 .  {* The contents of this section are to be sorted based on the sum of
256 .     the symbol and addend values specified by the associated relocation
257 .     entries.  Entries without associated relocation entries will be
258 .     appended to the end of the section in an unspecified order.  *}
259 .#define SEC_SORT_ENTRIES 0x10000
260 .
261 .  {* When linking, duplicate sections of the same name should be
262 .     discarded, rather than being combined into a single section as
263 .     is usually done.  This is similar to how common symbols are
264 .     handled.  See SEC_LINK_DUPLICATES below.  *}
265 .#define SEC_LINK_ONCE 0x20000
266 .
267 .  {* If SEC_LINK_ONCE is set, this bitfield describes how the linker
268 .     should handle duplicate sections.  *}
269 .#define SEC_LINK_DUPLICATES 0xc0000
270 .
271 .  {* This value for SEC_LINK_DUPLICATES means that duplicate
272 .     sections with the same name should simply be discarded.  *}
273 .#define SEC_LINK_DUPLICATES_DISCARD 0x0
274 .
275 .  {* This value for SEC_LINK_DUPLICATES means that the linker
276 .     should warn if there are any duplicate sections, although
277 .     it should still only link one copy.  *}
278 .#define SEC_LINK_DUPLICATES_ONE_ONLY 0x40000
279 .
280 .  {* This value for SEC_LINK_DUPLICATES means that the linker
281 .     should warn if any duplicate sections are a different size.  *}
282 .#define SEC_LINK_DUPLICATES_SAME_SIZE 0x80000
283 .
284 .  {* This value for SEC_LINK_DUPLICATES means that the linker
285 .     should warn if any duplicate sections contain different
286 .     contents.  *}
287 .#define SEC_LINK_DUPLICATES_SAME_CONTENTS \
288 .  (SEC_LINK_DUPLICATES_ONE_ONLY | SEC_LINK_DUPLICATES_SAME_SIZE)
289 .
290 .  {* This section was created by the linker as part of dynamic
291 .     relocation or other arcane processing.  It is skipped when
292 .     going through the first-pass output, trusting that someone
293 .     else up the line will take care of it later.  *}
294 .#define SEC_LINKER_CREATED 0x100000
295 .
296 .  {* This section should not be subject to garbage collection.
297 .     Also set to inform the linker that this section should not be
298 .     listed in the link map as discarded.  *}
299 .#define SEC_KEEP 0x200000
300 .
301 .  {* This section contains "short" data, and should be placed
302 .     "near" the GP.  *}
303 .#define SEC_SMALL_DATA 0x400000
304 .
305 .  {* Attempt to merge identical entities in the section.
306 .     Entity size is given in the entsize field.  *}
307 .#define SEC_MERGE 0x800000
308 .
309 .  {* If given with SEC_MERGE, entities to merge are zero terminated
310 .     strings where entsize specifies character size instead of fixed
311 .     size entries.  *}
312 .#define SEC_STRINGS 0x1000000
313 .
314 .  {* This section contains data about section groups.  *}
315 .#define SEC_GROUP 0x2000000
316 .
317 .  {* The section is a COFF shared library section.  This flag is
318 .     only for the linker.  If this type of section appears in
319 .     the input file, the linker must copy it to the output file
320 .     without changing the vma or size.  FIXME: Although this
321 .     was originally intended to be general, it really is COFF
322 .     specific (and the flag was renamed to indicate this).  It
323 .     might be cleaner to have some more general mechanism to
324 .     allow the back end to control what the linker does with
325 .     sections.  *}
326 .#define SEC_COFF_SHARED_LIBRARY 0x4000000
327 .
328 .  {* This input section should be copied to output in reverse order
329 .     as an array of pointers.  This is for ELF linker internal use
330 .     only.  *}
331 .#define SEC_ELF_REVERSE_COPY 0x4000000
332 .
333 .  {* This section contains data which may be shared with other
334 .     executables or shared objects. This is for COFF only.  *}
335 .#define SEC_COFF_SHARED 0x8000000
336 .
337 .  {* This section should be compressed.  This is for ELF linker
338 .     internal use only.  *}
339 .#define SEC_ELF_COMPRESS 0x8000000
340 .
341 .  {* When a section with this flag is being linked, then if the size of
342 .     the input section is less than a page, it should not cross a page
343 .     boundary.  If the size of the input section is one page or more,
344 .     it should be aligned on a page boundary.  This is for TI
345 .     TMS320C54X only.  *}
346 .#define SEC_TIC54X_BLOCK 0x10000000
347 .
348 .  {* This section should be renamed.  This is for ELF linker
349 .     internal use only.  *}
350 .#define SEC_ELF_RENAME 0x10000000
351 .
352 .  {* Conditionally link this section; do not link if there are no
353 .     references found to any symbol in the section.  This is for TI
354 .     TMS320C54X only.  *}
355 .#define SEC_TIC54X_CLINK 0x20000000
356 .
357 .  {* This section contains vliw code.  This is for Toshiba MeP only.  *}
358 .#define SEC_MEP_VLIW 0x20000000
359 .
360 .  {* Indicate that section has the no read flag set. This happens
361 .     when memory read flag isn't set. *}
362 .#define SEC_COFF_NOREAD 0x40000000
363 .
364 .  {* Indicate that section has the no read flag set.  *}
365 .#define SEC_ELF_NOREAD 0x80000000
366 .
367 .  {*  End of section flags.  *}
368 .
369 .  {* Some internal packed boolean fields.  *}
370 .
371 .  {* See the vma field.  *}
372 .  unsigned int user_set_vma : 1;
373 .
374 .  {* A mark flag used by some of the linker backends.  *}
375 .  unsigned int linker_mark : 1;
376 .
377 .  {* Another mark flag used by some of the linker backends.  Set for
378 .     output sections that have an input section.  *}
379 .  unsigned int linker_has_input : 1;
380 .
381 .  {* Mark flag used by some linker backends for garbage collection.  *}
382 .  unsigned int gc_mark : 1;
383 .
384 .  {* Section compression status.  *}
385 .  unsigned int compress_status : 2;
386 .#define COMPRESS_SECTION_NONE    0
387 .#define COMPRESS_SECTION_DONE    1
388 .#define DECOMPRESS_SECTION_SIZED 2
389 .
390 .  {* The following flags are used by the ELF linker. *}
391 .
392 .  {* Mark sections which have been allocated to segments.  *}
393 .  unsigned int segment_mark : 1;
394 .
395 .  {* Type of sec_info information.  *}
396 .  unsigned int sec_info_type:3;
397 .#define SEC_INFO_TYPE_NONE      0
398 .#define SEC_INFO_TYPE_STABS     1
399 .#define SEC_INFO_TYPE_MERGE     2
400 .#define SEC_INFO_TYPE_EH_FRAME  3
401 .#define SEC_INFO_TYPE_JUST_SYMS 4
402 .#define SEC_INFO_TYPE_TARGET    5
403 .#define SEC_INFO_TYPE_EH_FRAME_ENTRY 6
404 .
405 .  {* Nonzero if this section uses RELA relocations, rather than REL.  *}
406 .  unsigned int use_rela_p:1;
407 .
408 .  {* Bits used by various backends.  The generic code doesn't touch
409 .     these fields.  *}
410 .
411 .  unsigned int sec_flg0:1;
412 .  unsigned int sec_flg1:1;
413 .  unsigned int sec_flg2:1;
414 .  unsigned int sec_flg3:1;
415 .  unsigned int sec_flg4:1;
416 .  unsigned int sec_flg5:1;
417 .
418 .  {* End of internal packed boolean fields.  *}
419 .
420 .  {*  The virtual memory address of the section - where it will be
421 .      at run time.  The symbols are relocated against this.  The
422 .      user_set_vma flag is maintained by bfd; if it's not set, the
423 .      backend can assign addresses (for example, in <<a.out>>, where
424 .      the default address for <<.data>> is dependent on the specific
425 .      target and various flags).  *}
426 .  bfd_vma vma;
427 .
428 .  {*  The load address of the section - where it would be in a
429 .      rom image; really only used for writing section header
430 .      information.  *}
431 .  bfd_vma lma;
432 .
433 .  {* The size of the section in *octets*, as it will be output.
434 .     Contains a value even if the section has no contents (e.g., the
435 .     size of <<.bss>>).  *}
436 .  bfd_size_type size;
437 .
438 .  {* For input sections, the original size on disk of the section, in
439 .     octets.  This field should be set for any section whose size is
440 .     changed by linker relaxation.  It is required for sections where
441 .     the linker relaxation scheme doesn't cache altered section and
442 .     reloc contents (stabs, eh_frame, SEC_MERGE, some coff relaxing
443 .     targets), and thus the original size needs to be kept to read the
444 .     section multiple times.  For output sections, rawsize holds the
445 .     section size calculated on a previous linker relaxation pass.  *}
446 .  bfd_size_type rawsize;
447 .
448 .  {* The compressed size of the section in octets.  *}
449 .  bfd_size_type compressed_size;
450 .
451 .  {* Relaxation table. *}
452 .  struct relax_table *relax;
453 .
454 .  {* Count of used relaxation table entries. *}
455 .  int relax_count;
456 .
457 .
458 .  {* If this section is going to be output, then this value is the
459 .     offset in *bytes* into the output section of the first byte in the
460 .     input section (byte ==> smallest addressable unit on the
461 .     target).  In most cases, if this was going to start at the
462 .     100th octet (8-bit quantity) in the output section, this value
463 .     would be 100.  However, if the target byte size is 16 bits
464 .     (bfd_octets_per_byte is "2"), this value would be 50.  *}
465 .  bfd_vma output_offset;
466 .
467 .  {* The output section through which to map on output.  *}
468 .  struct bfd_section *output_section;
469 .
470 .  {* The alignment requirement of the section, as an exponent of 2 -
471 .     e.g., 3 aligns to 2^3 (or 8).  *}
472 .  unsigned int alignment_power;
473 .
474 .  {* If an input section, a pointer to a vector of relocation
475 .     records for the data in this section.  *}
476 .  struct reloc_cache_entry *relocation;
477 .
478 .  {* If an output section, a pointer to a vector of pointers to
479 .     relocation records for the data in this section.  *}
480 .  struct reloc_cache_entry **orelocation;
481 .
482 .  {* The number of relocation records in one of the above.  *}
483 .  unsigned reloc_count;
484 .
485 .  {* Information below is back end specific - and not always used
486 .     or updated.  *}
487 .
488 .  {* File position of section data.  *}
489 .  file_ptr filepos;
490 .
491 .  {* File position of relocation info.  *}
492 .  file_ptr rel_filepos;
493 .
494 .  {* File position of line data.  *}
495 .  file_ptr line_filepos;
496 .
497 .  {* Pointer to data for applications.  *}
498 .  void *userdata;
499 .
500 .  {* If the SEC_IN_MEMORY flag is set, this points to the actual
501 .     contents.  *}
502 .  unsigned char *contents;
503 .
504 .  {* Attached line number information.  *}
505 .  alent *lineno;
506 .
507 .  {* Number of line number records.  *}
508 .  unsigned int lineno_count;
509 .
510 .  {* Entity size for merging purposes.  *}
511 .  unsigned int entsize;
512 .
513 .  {* Points to the kept section if this section is a link-once section,
514 .     and is discarded.  *}
515 .  struct bfd_section *kept_section;
516 .
517 .  {* When a section is being output, this value changes as more
518 .     linenumbers are written out.  *}
519 .  file_ptr moving_line_filepos;
520 .
521 .  {* What the section number is in the target world.  *}
522 .  int target_index;
523 .
524 .  void *used_by_bfd;
525 .
526 .  {* If this is a constructor section then here is a list of the
527 .     relocations created to relocate items within it.  *}
528 .  struct relent_chain *constructor_chain;
529 .
530 .  {* The BFD which owns the section.  *}
531 .  bfd *owner;
532 .
533 .  {* A symbol which points at this section only.  *}
534 .  struct bfd_symbol *symbol;
535 .  struct bfd_symbol **symbol_ptr_ptr;
536 .
537 .  {* Early in the link process, map_head and map_tail are used to build
538 .     a list of input sections attached to an output section.  Later,
539 .     output sections use these fields for a list of bfd_link_order
540 .     structs.  *}
541 .  union {
542 .    struct bfd_link_order *link_order;
543 .    struct bfd_section *s;
544 .  } map_head, map_tail;
545 .} asection;
546 .
547 .{* Relax table contains information about instructions which can
548 .   be removed by relaxation -- replacing a long address with a
549 .   short address.  *}
550 .struct relax_table {
551 .  {* Address where bytes may be deleted. *}
552 .  bfd_vma addr;
553 .
554 .  {* Number of bytes to be deleted.  *}
555 .  int size;
556 .};
557 .
558 .{* Note: the following are provided as inline functions rather than macros
559 .   because not all callers use the return value.  A macro implementation
560 .   would use a comma expression, eg: "((ptr)->foo = val, TRUE)" and some
561 .   compilers will complain about comma expressions that have no effect.  *}
562 .static inline bfd_boolean
563 .bfd_set_section_userdata (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, void * val)
564 .{
565 .  ptr->userdata = val;
566 .  return TRUE;
567 .}
568 .
569 .static inline bfd_boolean
570 .bfd_set_section_vma (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, bfd_vma val)
571 .{
572 .  ptr->vma = ptr->lma = val;
573 .  ptr->user_set_vma = TRUE;
574 .  return TRUE;
575 .}
576 .
577 .static inline bfd_boolean
578 .bfd_set_section_alignment (bfd * abfd ATTRIBUTE_UNUSED, asection * ptr, unsigned int val)
579 .{
580 .  ptr->alignment_power = val;
581 .  return TRUE;
582 .}
583 .
584 .{* These sections are global, and are managed by BFD.  The application
585 .   and target back end are not permitted to change the values in
586 .   these sections.  *}
587 .extern asection _bfd_std_section[4];
588 .
589 .#define BFD_ABS_SECTION_NAME "*ABS*"
590 .#define BFD_UND_SECTION_NAME "*UND*"
591 .#define BFD_COM_SECTION_NAME "*COM*"
592 .#define BFD_IND_SECTION_NAME "*IND*"
593 .
594 .{* Pointer to the common section.  *}
595 .#define bfd_com_section_ptr (&_bfd_std_section[0])
596 .{* Pointer to the undefined section.  *}
597 .#define bfd_und_section_ptr (&_bfd_std_section[1])
598 .{* Pointer to the absolute section.  *}
599 .#define bfd_abs_section_ptr (&_bfd_std_section[2])
600 .{* Pointer to the indirect section.  *}
601 .#define bfd_ind_section_ptr (&_bfd_std_section[3])
602 .
603 .#define bfd_is_und_section(sec) ((sec) == bfd_und_section_ptr)
604 .#define bfd_is_abs_section(sec) ((sec) == bfd_abs_section_ptr)
605 .#define bfd_is_ind_section(sec) ((sec) == bfd_ind_section_ptr)
606 .
607 .#define bfd_is_const_section(SEC)		\
608 . (   ((SEC) == bfd_abs_section_ptr)		\
609 .  || ((SEC) == bfd_und_section_ptr)		\
610 .  || ((SEC) == bfd_com_section_ptr)		\
611 .  || ((SEC) == bfd_ind_section_ptr))
612 .
613 .{* Macros to handle insertion and deletion of a bfd's sections.  These
614 .   only handle the list pointers, ie. do not adjust section_count,
615 .   target_index etc.  *}
616 .#define bfd_section_list_remove(ABFD, S) \
617 .  do							\
618 .    {							\
619 .      asection *_s = S;				\
620 .      asection *_next = _s->next;			\
621 .      asection *_prev = _s->prev;			\
622 .      if (_prev)					\
623 .        _prev->next = _next;				\
624 .      else						\
625 .        (ABFD)->sections = _next;			\
626 .      if (_next)					\
627 .        _next->prev = _prev;				\
628 .      else						\
629 .        (ABFD)->section_last = _prev;			\
630 .    }							\
631 .  while (0)
632 .#define bfd_section_list_append(ABFD, S) \
633 .  do							\
634 .    {							\
635 .      asection *_s = S;				\
636 .      bfd *_abfd = ABFD;				\
637 .      _s->next = NULL;					\
638 .      if (_abfd->section_last)				\
639 .        {						\
640 .          _s->prev = _abfd->section_last;		\
641 .          _abfd->section_last->next = _s;		\
642 .        }						\
643 .      else						\
644 .        {						\
645 .          _s->prev = NULL;				\
646 .          _abfd->sections = _s;			\
647 .        }						\
648 .      _abfd->section_last = _s;			\
649 .    }							\
650 .  while (0)
651 .#define bfd_section_list_prepend(ABFD, S) \
652 .  do							\
653 .    {							\
654 .      asection *_s = S;				\
655 .      bfd *_abfd = ABFD;				\
656 .      _s->prev = NULL;					\
657 .      if (_abfd->sections)				\
658 .        {						\
659 .          _s->next = _abfd->sections;			\
660 .          _abfd->sections->prev = _s;			\
661 .        }						\
662 .      else						\
663 .        {						\
664 .          _s->next = NULL;				\
665 .          _abfd->section_last = _s;			\
666 .        }						\
667 .      _abfd->sections = _s;				\
668 .    }							\
669 .  while (0)
670 .#define bfd_section_list_insert_after(ABFD, A, S) \
671 .  do							\
672 .    {							\
673 .      asection *_a = A;				\
674 .      asection *_s = S;				\
675 .      asection *_next = _a->next;			\
676 .      _s->next = _next;				\
677 .      _s->prev = _a;					\
678 .      _a->next = _s;					\
679 .      if (_next)					\
680 .        _next->prev = _s;				\
681 .      else						\
682 .        (ABFD)->section_last = _s;			\
683 .    }							\
684 .  while (0)
685 .#define bfd_section_list_insert_before(ABFD, B, S) \
686 .  do							\
687 .    {							\
688 .      asection *_b = B;				\
689 .      asection *_s = S;				\
690 .      asection *_prev = _b->prev;			\
691 .      _s->prev = _prev;				\
692 .      _s->next = _b;					\
693 .      _b->prev = _s;					\
694 .      if (_prev)					\
695 .        _prev->next = _s;				\
696 .      else						\
697 .        (ABFD)->sections = _s;				\
698 .    }							\
699 .  while (0)
700 .#define bfd_section_removed_from_list(ABFD, S) \
701 .  ((S)->next == NULL ? (ABFD)->section_last != (S) : (S)->next->prev != (S))
702 .
703 .#define BFD_FAKE_SECTION(SEC, FLAGS, SYM, NAME, IDX)			\
704 .  {* name, id,  index, next, prev, flags, user_set_vma,            *}	\
705 .  { NAME,  IDX, 0,     NULL, NULL, FLAGS, 0,				\
706 .									\
707 .  {* linker_mark, linker_has_input, gc_mark, decompress_status,    *}	\
708 .     0,           0,                1,       0,			\
709 .									\
710 .  {* segment_mark, sec_info_type, use_rela_p,                      *}	\
711 .     0,            0,             0,					\
712 .									\
713 .  {* sec_flg0, sec_flg1, sec_flg2, sec_flg3, sec_flg4, sec_flg5,   *}	\
714 .     0,        0,        0,        0,        0,        0,		\
715 .									\
716 .  {* vma, lma, size, rawsize, compressed_size, relax, relax_count, *}	\
717 .     0,   0,   0,    0,       0,               0,     0,		\
718 .									\
719 .  {* output_offset, output_section, alignment_power,               *}	\
720 .     0,             &SEC,           0,					\
721 .									\
722 .  {* relocation, orelocation, reloc_count, filepos, rel_filepos,   *}	\
723 .     NULL,       NULL,        0,           0,       0,			\
724 .									\
725 .  {* line_filepos, userdata, contents, lineno, lineno_count,       *}	\
726 .     0,            NULL,     NULL,     NULL,   0,			\
727 .									\
728 .  {* entsize, kept_section, moving_line_filepos,		     *}	\
729 .     0,       NULL,	      0,					\
730 .									\
731 .  {* target_index, used_by_bfd, constructor_chain, owner,          *}	\
732 .     0,            NULL,        NULL,              NULL,		\
733 .									\
734 .  {* symbol,                    symbol_ptr_ptr,                    *}	\
735 .     (struct bfd_symbol *) SYM, &SEC.symbol,				\
736 .									\
737 .  {* map_head, map_tail                                            *}	\
738 .     { NULL }, { NULL }						\
739 .    }
740 .
741 */
742 
743 /* We use a macro to initialize the static asymbol structures because
744    traditional C does not permit us to initialize a union member while
745    gcc warns if we don't initialize it.  */
746  /* the_bfd, name, value, attr, section [, udata] */
747 #ifdef __STDC__
748 #define GLOBAL_SYM_INIT(NAME, SECTION) \
749   { 0, NAME, 0, BSF_SECTION_SYM, SECTION, { 0 }}
750 #else
751 #define GLOBAL_SYM_INIT(NAME, SECTION) \
752   { 0, NAME, 0, BSF_SECTION_SYM, SECTION }
753 #endif
754 
755 /* These symbols are global, not specific to any BFD.  Therefore, anything
756    that tries to change them is broken, and should be repaired.  */
757 
758 static const asymbol global_syms[] =
759 {
760   GLOBAL_SYM_INIT (BFD_COM_SECTION_NAME, bfd_com_section_ptr),
761   GLOBAL_SYM_INIT (BFD_UND_SECTION_NAME, bfd_und_section_ptr),
762   GLOBAL_SYM_INIT (BFD_ABS_SECTION_NAME, bfd_abs_section_ptr),
763   GLOBAL_SYM_INIT (BFD_IND_SECTION_NAME, bfd_ind_section_ptr)
764 };
765 
766 #define STD_SECTION(NAME, IDX, FLAGS) \
767   BFD_FAKE_SECTION(_bfd_std_section[IDX], FLAGS, &global_syms[IDX], NAME, IDX)
768 
769 asection _bfd_std_section[] = {
770   STD_SECTION (BFD_COM_SECTION_NAME, 0, SEC_IS_COMMON),
771   STD_SECTION (BFD_UND_SECTION_NAME, 1, 0),
772   STD_SECTION (BFD_ABS_SECTION_NAME, 2, 0),
773   STD_SECTION (BFD_IND_SECTION_NAME, 3, 0)
774 };
775 #undef STD_SECTION
776 
777 /* Initialize an entry in the section hash table.  */
778 
779 struct bfd_hash_entry *
bfd_section_hash_newfunc(struct bfd_hash_entry * entry,struct bfd_hash_table * table,const char * string)780 bfd_section_hash_newfunc (struct bfd_hash_entry *entry,
781 			  struct bfd_hash_table *table,
782 			  const char *string)
783 {
784   /* Allocate the structure if it has not already been allocated by a
785      subclass.  */
786   if (entry == NULL)
787     {
788       entry = (struct bfd_hash_entry *)
789 	bfd_hash_allocate (table, sizeof (struct section_hash_entry));
790       if (entry == NULL)
791 	return entry;
792     }
793 
794   /* Call the allocation method of the superclass.  */
795   entry = bfd_hash_newfunc (entry, table, string);
796   if (entry != NULL)
797     memset (&((struct section_hash_entry *) entry)->section, 0,
798 	    sizeof (asection));
799 
800   return entry;
801 }
802 
803 #define section_hash_lookup(table, string, create, copy) \
804   ((struct section_hash_entry *) \
805    bfd_hash_lookup ((table), (string), (create), (copy)))
806 
807 /* Create a symbol whose only job is to point to this section.  This
808    is useful for things like relocs which are relative to the base
809    of a section.  */
810 
811 bfd_boolean
_bfd_generic_new_section_hook(bfd * abfd,asection * newsect)812 _bfd_generic_new_section_hook (bfd *abfd, asection *newsect)
813 {
814   newsect->symbol = bfd_make_empty_symbol (abfd);
815   if (newsect->symbol == NULL)
816     return FALSE;
817 
818   newsect->symbol->name = newsect->name;
819   newsect->symbol->value = 0;
820   newsect->symbol->section = newsect;
821   newsect->symbol->flags = BSF_SECTION_SYM;
822 
823   newsect->symbol_ptr_ptr = &newsect->symbol;
824   return TRUE;
825 }
826 
827 static unsigned int section_id = 0x10;  /* id 0 to 3 used by STD_SECTION.  */
828 
829 /* Initializes a new section.  NEWSECT->NAME is already set.  */
830 
831 static asection *
bfd_section_init(bfd * abfd,asection * newsect)832 bfd_section_init (bfd *abfd, asection *newsect)
833 {
834   newsect->id = section_id;
835   newsect->index = abfd->section_count;
836   newsect->owner = abfd;
837 
838   if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect)))
839     return NULL;
840 
841   section_id++;
842   abfd->section_count++;
843   bfd_section_list_append (abfd, newsect);
844   return newsect;
845 }
846 
847 /*
848 DOCDD
849 INODE
850 section prototypes,  , typedef asection, Sections
851 SUBSECTION
852 	Section prototypes
853 
854 These are the functions exported by the section handling part of BFD.
855 */
856 
857 /*
858 FUNCTION
859 	bfd_section_list_clear
860 
861 SYNOPSIS
862 	void bfd_section_list_clear (bfd *);
863 
864 DESCRIPTION
865 	Clears the section list, and also resets the section count and
866 	hash table entries.
867 */
868 
869 void
bfd_section_list_clear(bfd * abfd)870 bfd_section_list_clear (bfd *abfd)
871 {
872   abfd->sections = NULL;
873   abfd->section_last = NULL;
874   abfd->section_count = 0;
875   memset (abfd->section_htab.table, 0,
876 	  abfd->section_htab.size * sizeof (struct bfd_hash_entry *));
877   abfd->section_htab.count = 0;
878 }
879 
880 /*
881 FUNCTION
882 	bfd_get_section_by_name
883 
884 SYNOPSIS
885 	asection *bfd_get_section_by_name (bfd *abfd, const char *name);
886 
887 DESCRIPTION
888 	Return the most recently created section attached to @var{abfd}
889 	named @var{name}.  Return NULL if no such section exists.
890 */
891 
892 asection *
bfd_get_section_by_name(bfd * abfd,const char * name)893 bfd_get_section_by_name (bfd *abfd, const char *name)
894 {
895   struct section_hash_entry *sh;
896 
897   sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE);
898   if (sh != NULL)
899     return &sh->section;
900 
901   return NULL;
902 }
903 
904 /*
905 FUNCTION
906        bfd_get_next_section_by_name
907 
908 SYNOPSIS
909        asection *bfd_get_next_section_by_name (bfd *ibfd, asection *sec);
910 
911 DESCRIPTION
912        Given @var{sec} is a section returned by @code{bfd_get_section_by_name},
913        return the next most recently created section attached to the same
914        BFD with the same name, or if no such section exists in the same BFD and
915        IBFD is non-NULL, the next section with the same name in any input
916        BFD following IBFD.  Return NULL on finding no section.
917 */
918 
919 asection *
bfd_get_next_section_by_name(bfd * ibfd,asection * sec)920 bfd_get_next_section_by_name (bfd *ibfd, asection *sec)
921 {
922   struct section_hash_entry *sh;
923   const char *name;
924   unsigned long hash;
925 
926   sh = ((struct section_hash_entry *)
927 	((char *) sec - offsetof (struct section_hash_entry, section)));
928 
929   hash = sh->root.hash;
930   name = sec->name;
931   for (sh = (struct section_hash_entry *) sh->root.next;
932        sh != NULL;
933        sh = (struct section_hash_entry *) sh->root.next)
934     if (sh->root.hash == hash
935        && strcmp (sh->root.string, name) == 0)
936       return &sh->section;
937 
938   if (ibfd != NULL)
939     {
940       while ((ibfd = ibfd->link.next) != NULL)
941 	{
942 	  asection *s = bfd_get_section_by_name (ibfd, name);
943 	  if (s != NULL)
944 	    return s;
945 	}
946     }
947 
948   return NULL;
949 }
950 
951 /*
952 FUNCTION
953 	bfd_get_linker_section
954 
955 SYNOPSIS
956 	asection *bfd_get_linker_section (bfd *abfd, const char *name);
957 
958 DESCRIPTION
959 	Return the linker created section attached to @var{abfd}
960 	named @var{name}.  Return NULL if no such section exists.
961 */
962 
963 asection *
bfd_get_linker_section(bfd * abfd,const char * name)964 bfd_get_linker_section (bfd *abfd, const char *name)
965 {
966   asection *sec = bfd_get_section_by_name (abfd, name);
967 
968   while (sec != NULL && (sec->flags & SEC_LINKER_CREATED) == 0)
969     sec = bfd_get_next_section_by_name (NULL, sec);
970   return sec;
971 }
972 
973 /*
974 FUNCTION
975 	bfd_get_section_by_name_if
976 
977 SYNOPSIS
978 	asection *bfd_get_section_by_name_if
979 	  (bfd *abfd,
980 	   const char *name,
981 	   bfd_boolean (*func) (bfd *abfd, asection *sect, void *obj),
982 	   void *obj);
983 
984 DESCRIPTION
985 	Call the provided function @var{func} for each section
986 	attached to the BFD @var{abfd} whose name matches @var{name},
987 	passing @var{obj} as an argument. The function will be called
988 	as if by
989 
990 |	func (abfd, the_section, obj);
991 
992 	It returns the first section for which @var{func} returns true,
993 	otherwise <<NULL>>.
994 
995 */
996 
997 asection *
bfd_get_section_by_name_if(bfd * abfd,const char * name,bfd_boolean (* operation)(bfd *,asection *,void *),void * user_storage)998 bfd_get_section_by_name_if (bfd *abfd, const char *name,
999 			    bfd_boolean (*operation) (bfd *,
1000 						      asection *,
1001 						      void *),
1002 			    void *user_storage)
1003 {
1004   struct section_hash_entry *sh;
1005   unsigned long hash;
1006 
1007   sh = section_hash_lookup (&abfd->section_htab, name, FALSE, FALSE);
1008   if (sh == NULL)
1009     return NULL;
1010 
1011   hash = sh->root.hash;
1012   for (; sh != NULL; sh = (struct section_hash_entry *) sh->root.next)
1013     if (sh->root.hash == hash
1014 	&& strcmp (sh->root.string, name) == 0
1015 	&& (*operation) (abfd, &sh->section, user_storage))
1016       return &sh->section;
1017 
1018   return NULL;
1019 }
1020 
1021 /*
1022 FUNCTION
1023 	bfd_get_unique_section_name
1024 
1025 SYNOPSIS
1026 	char *bfd_get_unique_section_name
1027 	  (bfd *abfd, const char *templat, int *count);
1028 
1029 DESCRIPTION
1030 	Invent a section name that is unique in @var{abfd} by tacking
1031 	a dot and a digit suffix onto the original @var{templat}.  If
1032 	@var{count} is non-NULL, then it specifies the first number
1033 	tried as a suffix to generate a unique name.  The value
1034 	pointed to by @var{count} will be incremented in this case.
1035 */
1036 
1037 char *
bfd_get_unique_section_name(bfd * abfd,const char * templat,int * count)1038 bfd_get_unique_section_name (bfd *abfd, const char *templat, int *count)
1039 {
1040   int num;
1041   unsigned int len;
1042   char *sname;
1043 
1044   len = strlen (templat);
1045   sname = (char *) bfd_malloc (len + 8);
1046   if (sname == NULL)
1047     return NULL;
1048   memcpy (sname, templat, len);
1049   num = 1;
1050   if (count != NULL)
1051     num = *count;
1052 
1053   do
1054     {
1055       /* If we have a million sections, something is badly wrong.  */
1056       if (num > 999999)
1057 	abort ();
1058       sprintf (sname + len, ".%d", num++);
1059     }
1060   while (section_hash_lookup (&abfd->section_htab, sname, FALSE, FALSE));
1061 
1062   if (count != NULL)
1063     *count = num;
1064   return sname;
1065 }
1066 
1067 /*
1068 FUNCTION
1069 	bfd_make_section_old_way
1070 
1071 SYNOPSIS
1072 	asection *bfd_make_section_old_way (bfd *abfd, const char *name);
1073 
1074 DESCRIPTION
1075 	Create a new empty section called @var{name}
1076 	and attach it to the end of the chain of sections for the
1077 	BFD @var{abfd}. An attempt to create a section with a name which
1078 	is already in use returns its pointer without changing the
1079 	section chain.
1080 
1081 	It has the funny name since this is the way it used to be
1082 	before it was rewritten....
1083 
1084 	Possible errors are:
1085 	o <<bfd_error_invalid_operation>> -
1086 	If output has already started for this BFD.
1087 	o <<bfd_error_no_memory>> -
1088 	If memory allocation fails.
1089 
1090 */
1091 
1092 asection *
bfd_make_section_old_way(bfd * abfd,const char * name)1093 bfd_make_section_old_way (bfd *abfd, const char *name)
1094 {
1095   asection *newsect;
1096 
1097   if (abfd->output_has_begun)
1098     {
1099       bfd_set_error (bfd_error_invalid_operation);
1100       return NULL;
1101     }
1102 
1103   if (strcmp (name, BFD_ABS_SECTION_NAME) == 0)
1104     newsect = bfd_abs_section_ptr;
1105   else if (strcmp (name, BFD_COM_SECTION_NAME) == 0)
1106     newsect = bfd_com_section_ptr;
1107   else if (strcmp (name, BFD_UND_SECTION_NAME) == 0)
1108     newsect = bfd_und_section_ptr;
1109   else if (strcmp (name, BFD_IND_SECTION_NAME) == 0)
1110     newsect = bfd_ind_section_ptr;
1111   else
1112     {
1113       struct section_hash_entry *sh;
1114 
1115       sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
1116       if (sh == NULL)
1117 	return NULL;
1118 
1119       newsect = &sh->section;
1120       if (newsect->name != NULL)
1121 	{
1122 	  /* Section already exists.  */
1123 	  return newsect;
1124 	}
1125 
1126       newsect->name = name;
1127       return bfd_section_init (abfd, newsect);
1128     }
1129 
1130   /* Call new_section_hook when "creating" the standard abs, com, und
1131      and ind sections to tack on format specific section data.
1132      Also, create a proper section symbol.  */
1133   if (! BFD_SEND (abfd, _new_section_hook, (abfd, newsect)))
1134     return NULL;
1135   return newsect;
1136 }
1137 
1138 /*
1139 FUNCTION
1140 	bfd_make_section_anyway_with_flags
1141 
1142 SYNOPSIS
1143 	asection *bfd_make_section_anyway_with_flags
1144 	  (bfd *abfd, const char *name, flagword flags);
1145 
1146 DESCRIPTION
1147    Create a new empty section called @var{name} and attach it to the end of
1148    the chain of sections for @var{abfd}.  Create a new section even if there
1149    is already a section with that name.  Also set the attributes of the
1150    new section to the value @var{flags}.
1151 
1152    Return <<NULL>> and set <<bfd_error>> on error; possible errors are:
1153    o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}.
1154    o <<bfd_error_no_memory>> - If memory allocation fails.
1155 */
1156 
1157 sec_ptr
bfd_make_section_anyway_with_flags(bfd * abfd,const char * name,flagword flags)1158 bfd_make_section_anyway_with_flags (bfd *abfd, const char *name,
1159 				    flagword flags)
1160 {
1161   struct section_hash_entry *sh;
1162   asection *newsect;
1163 
1164   if (abfd->output_has_begun)
1165     {
1166       bfd_set_error (bfd_error_invalid_operation);
1167       return NULL;
1168     }
1169 
1170   sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
1171   if (sh == NULL)
1172     return NULL;
1173 
1174   newsect = &sh->section;
1175   if (newsect->name != NULL)
1176     {
1177       /* We are making a section of the same name.  Put it in the
1178 	 section hash table.  Even though we can't find it directly by a
1179 	 hash lookup, we'll be able to find the section by traversing
1180 	 sh->root.next quicker than looking at all the bfd sections.  */
1181       struct section_hash_entry *new_sh;
1182       new_sh = (struct section_hash_entry *)
1183 	bfd_section_hash_newfunc (NULL, &abfd->section_htab, name);
1184       if (new_sh == NULL)
1185 	return NULL;
1186 
1187       new_sh->root = sh->root;
1188       sh->root.next = &new_sh->root;
1189       newsect = &new_sh->section;
1190     }
1191 
1192   newsect->flags = flags;
1193   newsect->name = name;
1194   return bfd_section_init (abfd, newsect);
1195 }
1196 
1197 /*
1198 FUNCTION
1199 	bfd_make_section_anyway
1200 
1201 SYNOPSIS
1202 	asection *bfd_make_section_anyway (bfd *abfd, const char *name);
1203 
1204 DESCRIPTION
1205    Create a new empty section called @var{name} and attach it to the end of
1206    the chain of sections for @var{abfd}.  Create a new section even if there
1207    is already a section with that name.
1208 
1209    Return <<NULL>> and set <<bfd_error>> on error; possible errors are:
1210    o <<bfd_error_invalid_operation>> - If output has already started for @var{abfd}.
1211    o <<bfd_error_no_memory>> - If memory allocation fails.
1212 */
1213 
1214 sec_ptr
bfd_make_section_anyway(bfd * abfd,const char * name)1215 bfd_make_section_anyway (bfd *abfd, const char *name)
1216 {
1217   return bfd_make_section_anyway_with_flags (abfd, name, 0);
1218 }
1219 
1220 /*
1221 FUNCTION
1222 	bfd_make_section_with_flags
1223 
1224 SYNOPSIS
1225 	asection *bfd_make_section_with_flags
1226 	  (bfd *, const char *name, flagword flags);
1227 
1228 DESCRIPTION
1229    Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling
1230    bfd_set_error ()) without changing the section chain if there is already a
1231    section named @var{name}.  Also set the attributes of the new section to
1232    the value @var{flags}.  If there is an error, return <<NULL>> and set
1233    <<bfd_error>>.
1234 */
1235 
1236 asection *
bfd_make_section_with_flags(bfd * abfd,const char * name,flagword flags)1237 bfd_make_section_with_flags (bfd *abfd, const char *name,
1238 			     flagword flags)
1239 {
1240   struct section_hash_entry *sh;
1241   asection *newsect;
1242 
1243   if (abfd->output_has_begun)
1244     {
1245       bfd_set_error (bfd_error_invalid_operation);
1246       return NULL;
1247     }
1248 
1249   if (strcmp (name, BFD_ABS_SECTION_NAME) == 0
1250       || strcmp (name, BFD_COM_SECTION_NAME) == 0
1251       || strcmp (name, BFD_UND_SECTION_NAME) == 0
1252       || strcmp (name, BFD_IND_SECTION_NAME) == 0)
1253     return NULL;
1254 
1255   sh = section_hash_lookup (&abfd->section_htab, name, TRUE, FALSE);
1256   if (sh == NULL)
1257     return NULL;
1258 
1259   newsect = &sh->section;
1260   if (newsect->name != NULL)
1261     {
1262       /* Section already exists.  */
1263       return NULL;
1264     }
1265 
1266   newsect->name = name;
1267   newsect->flags = flags;
1268   return bfd_section_init (abfd, newsect);
1269 }
1270 
1271 /*
1272 FUNCTION
1273 	bfd_make_section
1274 
1275 SYNOPSIS
1276 	asection *bfd_make_section (bfd *, const char *name);
1277 
1278 DESCRIPTION
1279    Like <<bfd_make_section_anyway>>, but return <<NULL>> (without calling
1280    bfd_set_error ()) without changing the section chain if there is already a
1281    section named @var{name}.  If there is an error, return <<NULL>> and set
1282    <<bfd_error>>.
1283 */
1284 
1285 asection *
bfd_make_section(bfd * abfd,const char * name)1286 bfd_make_section (bfd *abfd, const char *name)
1287 {
1288   return bfd_make_section_with_flags (abfd, name, 0);
1289 }
1290 
1291 /*
1292 FUNCTION
1293 	bfd_get_next_section_id
1294 
1295 SYNOPSIS
1296 	int bfd_get_next_section_id (void);
1297 
1298 DESCRIPTION
1299 	Returns the id that the next section created will have.
1300 */
1301 
1302 int
bfd_get_next_section_id(void)1303 bfd_get_next_section_id (void)
1304 {
1305   return section_id;
1306 }
1307 
1308 /*
1309 FUNCTION
1310 	bfd_set_section_flags
1311 
1312 SYNOPSIS
1313 	bfd_boolean bfd_set_section_flags
1314 	  (bfd *abfd, asection *sec, flagword flags);
1315 
1316 DESCRIPTION
1317 	Set the attributes of the section @var{sec} in the BFD
1318 	@var{abfd} to the value @var{flags}. Return <<TRUE>> on success,
1319 	<<FALSE>> on error. Possible error returns are:
1320 
1321 	o <<bfd_error_invalid_operation>> -
1322 	The section cannot have one or more of the attributes
1323 	requested. For example, a .bss section in <<a.out>> may not
1324 	have the <<SEC_HAS_CONTENTS>> field set.
1325 
1326 */
1327 
1328 bfd_boolean
bfd_set_section_flags(bfd * abfd ATTRIBUTE_UNUSED,sec_ptr section,flagword flags)1329 bfd_set_section_flags (bfd *abfd ATTRIBUTE_UNUSED,
1330 		       sec_ptr section,
1331 		       flagword flags)
1332 {
1333   section->flags = flags;
1334   return TRUE;
1335 }
1336 
1337 /*
1338 FUNCTION
1339 	bfd_rename_section
1340 
1341 SYNOPSIS
1342 	void bfd_rename_section
1343 	  (bfd *abfd, asection *sec, const char *newname);
1344 
1345 DESCRIPTION
1346 	Rename section @var{sec} in @var{abfd} to @var{newname}.
1347 */
1348 
1349 void
bfd_rename_section(bfd * abfd,sec_ptr sec,const char * newname)1350 bfd_rename_section (bfd *abfd, sec_ptr sec, const char *newname)
1351 {
1352   struct section_hash_entry *sh;
1353 
1354   sh = (struct section_hash_entry *)
1355     ((char *) sec - offsetof (struct section_hash_entry, section));
1356   sh->section.name = newname;
1357   bfd_hash_rename (&abfd->section_htab, newname, &sh->root);
1358 }
1359 
1360 /*
1361 FUNCTION
1362 	bfd_map_over_sections
1363 
1364 SYNOPSIS
1365 	void bfd_map_over_sections
1366 	  (bfd *abfd,
1367 	   void (*func) (bfd *abfd, asection *sect, void *obj),
1368 	   void *obj);
1369 
1370 DESCRIPTION
1371 	Call the provided function @var{func} for each section
1372 	attached to the BFD @var{abfd}, passing @var{obj} as an
1373 	argument. The function will be called as if by
1374 
1375 |	func (abfd, the_section, obj);
1376 
1377 	This is the preferred method for iterating over sections; an
1378 	alternative would be to use a loop:
1379 
1380 |	   asection *p;
1381 |	   for (p = abfd->sections; p != NULL; p = p->next)
1382 |	      func (abfd, p, ...)
1383 
1384 */
1385 
1386 void
bfd_map_over_sections(bfd * abfd,void (* operation)(bfd *,asection *,void *),void * user_storage)1387 bfd_map_over_sections (bfd *abfd,
1388 		       void (*operation) (bfd *, asection *, void *),
1389 		       void *user_storage)
1390 {
1391   asection *sect;
1392   unsigned int i = 0;
1393 
1394   for (sect = abfd->sections; sect != NULL; i++, sect = sect->next)
1395     (*operation) (abfd, sect, user_storage);
1396 
1397   if (i != abfd->section_count)	/* Debugging */
1398     abort ();
1399 }
1400 
1401 /*
1402 FUNCTION
1403 	bfd_sections_find_if
1404 
1405 SYNOPSIS
1406 	asection *bfd_sections_find_if
1407 	  (bfd *abfd,
1408 	   bfd_boolean (*operation) (bfd *abfd, asection *sect, void *obj),
1409 	   void *obj);
1410 
1411 DESCRIPTION
1412 	Call the provided function @var{operation} for each section
1413 	attached to the BFD @var{abfd}, passing @var{obj} as an
1414 	argument. The function will be called as if by
1415 
1416 |	operation (abfd, the_section, obj);
1417 
1418 	It returns the first section for which @var{operation} returns true.
1419 
1420 */
1421 
1422 asection *
bfd_sections_find_if(bfd * abfd,bfd_boolean (* operation)(bfd *,asection *,void *),void * user_storage)1423 bfd_sections_find_if (bfd *abfd,
1424 		      bfd_boolean (*operation) (bfd *, asection *, void *),
1425 		      void *user_storage)
1426 {
1427   asection *sect;
1428 
1429   for (sect = abfd->sections; sect != NULL; sect = sect->next)
1430     if ((*operation) (abfd, sect, user_storage))
1431       break;
1432 
1433   return sect;
1434 }
1435 
1436 /*
1437 FUNCTION
1438 	bfd_set_section_size
1439 
1440 SYNOPSIS
1441 	bfd_boolean bfd_set_section_size
1442 	  (bfd *abfd, asection *sec, bfd_size_type val);
1443 
1444 DESCRIPTION
1445 	Set @var{sec} to the size @var{val}. If the operation is
1446 	ok, then <<TRUE>> is returned, else <<FALSE>>.
1447 
1448 	Possible error returns:
1449 	o <<bfd_error_invalid_operation>> -
1450 	Writing has started to the BFD, so setting the size is invalid.
1451 
1452 */
1453 
1454 bfd_boolean
bfd_set_section_size(bfd * abfd,sec_ptr ptr,bfd_size_type val)1455 bfd_set_section_size (bfd *abfd, sec_ptr ptr, bfd_size_type val)
1456 {
1457   /* Once you've started writing to any section you cannot create or change
1458      the size of any others.  */
1459 
1460   if (abfd->output_has_begun)
1461     {
1462       bfd_set_error (bfd_error_invalid_operation);
1463       return FALSE;
1464     }
1465 
1466   ptr->size = val;
1467   return TRUE;
1468 }
1469 
1470 /*
1471 FUNCTION
1472 	bfd_set_section_contents
1473 
1474 SYNOPSIS
1475 	bfd_boolean bfd_set_section_contents
1476 	  (bfd *abfd, asection *section, const void *data,
1477 	   file_ptr offset, bfd_size_type count);
1478 
1479 DESCRIPTION
1480 	Sets the contents of the section @var{section} in BFD
1481 	@var{abfd} to the data starting in memory at @var{data}. The
1482 	data is written to the output section starting at offset
1483 	@var{offset} for @var{count} octets.
1484 
1485 	Normally <<TRUE>> is returned, else <<FALSE>>. Possible error
1486 	returns are:
1487 	o <<bfd_error_no_contents>> -
1488 	The output section does not have the <<SEC_HAS_CONTENTS>>
1489 	attribute, so nothing can be written to it.
1490 	o and some more too
1491 
1492 	This routine is front end to the back end function
1493 	<<_bfd_set_section_contents>>.
1494 
1495 */
1496 
1497 bfd_boolean
bfd_set_section_contents(bfd * abfd,sec_ptr section,const void * location,file_ptr offset,bfd_size_type count)1498 bfd_set_section_contents (bfd *abfd,
1499 			  sec_ptr section,
1500 			  const void *location,
1501 			  file_ptr offset,
1502 			  bfd_size_type count)
1503 {
1504   bfd_size_type sz;
1505 
1506   if (!(bfd_get_section_flags (abfd, section) & SEC_HAS_CONTENTS))
1507     {
1508       bfd_set_error (bfd_error_no_contents);
1509       return FALSE;
1510     }
1511 
1512   sz = section->size;
1513   if ((bfd_size_type) offset > sz
1514       || count > sz
1515       || offset + count > sz
1516       || count != (size_t) count)
1517     {
1518       bfd_set_error (bfd_error_bad_value);
1519       return FALSE;
1520     }
1521 
1522   if (!bfd_write_p (abfd))
1523     {
1524       bfd_set_error (bfd_error_invalid_operation);
1525       return FALSE;
1526     }
1527 
1528   /* Record a copy of the data in memory if desired.  */
1529   if (section->contents
1530       && location != section->contents + offset)
1531     memcpy (section->contents + offset, location, (size_t) count);
1532 
1533   if (BFD_SEND (abfd, _bfd_set_section_contents,
1534 		(abfd, section, location, offset, count)))
1535     {
1536       abfd->output_has_begun = TRUE;
1537       return TRUE;
1538     }
1539 
1540   return FALSE;
1541 }
1542 
1543 /*
1544 FUNCTION
1545 	bfd_get_section_contents
1546 
1547 SYNOPSIS
1548 	bfd_boolean bfd_get_section_contents
1549 	  (bfd *abfd, asection *section, void *location, file_ptr offset,
1550 	   bfd_size_type count);
1551 
1552 DESCRIPTION
1553 	Read data from @var{section} in BFD @var{abfd}
1554 	into memory starting at @var{location}. The data is read at an
1555 	offset of @var{offset} from the start of the input section,
1556 	and is read for @var{count} bytes.
1557 
1558 	If the contents of a constructor with the <<SEC_CONSTRUCTOR>>
1559 	flag set are requested or if the section does not have the
1560 	<<SEC_HAS_CONTENTS>> flag set, then the @var{location} is filled
1561 	with zeroes. If no errors occur, <<TRUE>> is returned, else
1562 	<<FALSE>>.
1563 
1564 */
1565 bfd_boolean
bfd_get_section_contents(bfd * abfd,sec_ptr section,void * location,file_ptr offset,bfd_size_type count)1566 bfd_get_section_contents (bfd *abfd,
1567 			  sec_ptr section,
1568 			  void *location,
1569 			  file_ptr offset,
1570 			  bfd_size_type count)
1571 {
1572   bfd_size_type sz;
1573 
1574   if (section->flags & SEC_CONSTRUCTOR)
1575     {
1576       memset (location, 0, (size_t) count);
1577       return TRUE;
1578     }
1579 
1580   if (abfd->direction != write_direction && section->rawsize != 0)
1581     sz = section->rawsize;
1582   else
1583     sz = section->size;
1584   if ((bfd_size_type) offset > sz
1585       || count > sz
1586       || offset + count > sz
1587       || count != (size_t) count)
1588     {
1589       bfd_set_error (bfd_error_bad_value);
1590       return FALSE;
1591     }
1592 
1593   if (count == 0)
1594     /* Don't bother.  */
1595     return TRUE;
1596 
1597   if ((section->flags & SEC_HAS_CONTENTS) == 0)
1598     {
1599       memset (location, 0, (size_t) count);
1600       return TRUE;
1601     }
1602 
1603   if ((section->flags & SEC_IN_MEMORY) != 0)
1604     {
1605       if (section->contents == NULL)
1606 	{
1607 	  /* This can happen because of errors earlier on in the linking process.
1608 	     We do not want to seg-fault here, so clear the flag and return an
1609 	     error code.  */
1610 	  section->flags &= ~ SEC_IN_MEMORY;
1611 	  bfd_set_error (bfd_error_invalid_operation);
1612 	  return FALSE;
1613 	}
1614 
1615       memmove (location, section->contents + offset, (size_t) count);
1616       return TRUE;
1617     }
1618 
1619   return BFD_SEND (abfd, _bfd_get_section_contents,
1620 		   (abfd, section, location, offset, count));
1621 }
1622 
1623 /*
1624 FUNCTION
1625 	bfd_malloc_and_get_section
1626 
1627 SYNOPSIS
1628 	bfd_boolean bfd_malloc_and_get_section
1629 	  (bfd *abfd, asection *section, bfd_byte **buf);
1630 
1631 DESCRIPTION
1632 	Read all data from @var{section} in BFD @var{abfd}
1633 	into a buffer, *@var{buf}, malloc'd by this function.
1634 */
1635 
1636 bfd_boolean
bfd_malloc_and_get_section(bfd * abfd,sec_ptr sec,bfd_byte ** buf)1637 bfd_malloc_and_get_section (bfd *abfd, sec_ptr sec, bfd_byte **buf)
1638 {
1639   *buf = NULL;
1640   return bfd_get_full_section_contents (abfd, sec, buf);
1641 }
1642 /*
1643 FUNCTION
1644 	bfd_copy_private_section_data
1645 
1646 SYNOPSIS
1647 	bfd_boolean bfd_copy_private_section_data
1648 	  (bfd *ibfd, asection *isec, bfd *obfd, asection *osec);
1649 
1650 DESCRIPTION
1651 	Copy private section information from @var{isec} in the BFD
1652 	@var{ibfd} to the section @var{osec} in the BFD @var{obfd}.
1653 	Return <<TRUE>> on success, <<FALSE>> on error.  Possible error
1654 	returns are:
1655 
1656 	o <<bfd_error_no_memory>> -
1657 	Not enough memory exists to create private data for @var{osec}.
1658 
1659 .#define bfd_copy_private_section_data(ibfd, isection, obfd, osection) \
1660 .     BFD_SEND (obfd, _bfd_copy_private_section_data, \
1661 .		(ibfd, isection, obfd, osection))
1662 */
1663 
1664 /*
1665 FUNCTION
1666 	bfd_generic_is_group_section
1667 
1668 SYNOPSIS
1669 	bfd_boolean bfd_generic_is_group_section (bfd *, const asection *sec);
1670 
1671 DESCRIPTION
1672 	Returns TRUE if @var{sec} is a member of a group.
1673 */
1674 
1675 bfd_boolean
bfd_generic_is_group_section(bfd * abfd ATTRIBUTE_UNUSED,const asection * sec ATTRIBUTE_UNUSED)1676 bfd_generic_is_group_section (bfd *abfd ATTRIBUTE_UNUSED,
1677 			      const asection *sec ATTRIBUTE_UNUSED)
1678 {
1679   return FALSE;
1680 }
1681 
1682 /*
1683 FUNCTION
1684 	bfd_generic_discard_group
1685 
1686 SYNOPSIS
1687 	bfd_boolean bfd_generic_discard_group (bfd *abfd, asection *group);
1688 
1689 DESCRIPTION
1690 	Remove all members of @var{group} from the output.
1691 */
1692 
1693 bfd_boolean
bfd_generic_discard_group(bfd * abfd ATTRIBUTE_UNUSED,asection * group ATTRIBUTE_UNUSED)1694 bfd_generic_discard_group (bfd *abfd ATTRIBUTE_UNUSED,
1695 			   asection *group ATTRIBUTE_UNUSED)
1696 {
1697   return TRUE;
1698 }
1699