1 /* ldlang.h - linker command language support
2 Copyright (C) 1991-2022 Free Software Foundation, Inc.
3
4 This file is part of the GNU Binutils.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
19 MA 02110-1301, USA. */
20
21 #ifndef LDLANG_H
22 #define LDLANG_H
23
24 #define DEFAULT_MEMORY_REGION "*default*"
25
26 #define SECTION_NAME_MAP_LENGTH (16)
27
28 typedef enum
29 {
30 lang_input_file_is_l_enum,
31 lang_input_file_is_symbols_only_enum,
32 lang_input_file_is_marker_enum,
33 lang_input_file_is_fake_enum,
34 lang_input_file_is_search_file_enum,
35 lang_input_file_is_file_enum
36 } lang_input_file_enum_type;
37
38 struct _fill_type
39 {
40 size_t size;
41 unsigned char data[1];
42 };
43
44 typedef struct statement_list
45 {
46 union lang_statement_union * head;
47 union lang_statement_union ** tail;
48 } lang_statement_list_type;
49
50 typedef struct memory_region_name_struct
51 {
52 const char * name;
53 struct memory_region_name_struct * next;
54 } lang_memory_region_name;
55
56 typedef struct memory_region_struct
57 {
58 lang_memory_region_name name_list;
59 struct memory_region_struct *next;
60 union etree_union *origin_exp;
61 bfd_vma origin;
62 bfd_size_type length;
63 union etree_union *length_exp;
64 bfd_vma current;
65 union lang_statement_union *last_os;
66 flagword flags;
67 flagword not_flags;
68 bool had_full_message;
69 } lang_memory_region_type;
70
71 enum statement_enum
72 {
73 lang_address_statement_enum,
74 lang_assignment_statement_enum,
75 lang_data_statement_enum,
76 lang_fill_statement_enum,
77 lang_group_statement_enum,
78 lang_input_section_enum,
79 lang_input_statement_enum,
80 lang_insert_statement_enum,
81 lang_output_section_statement_enum,
82 lang_output_statement_enum,
83 lang_padding_statement_enum,
84 lang_reloc_statement_enum,
85 lang_target_statement_enum,
86 lang_wild_statement_enum,
87 lang_constructors_statement_enum,
88 lang_object_symbols_statement_enum
89 };
90
91 typedef struct lang_statement_header_struct
92 {
93 /* Next pointer for statement_list statement list. */
94 union lang_statement_union *next;
95 enum statement_enum type;
96 } lang_statement_header_type;
97
98 typedef struct
99 {
100 lang_statement_header_type header;
101 union etree_union *exp;
102 } lang_assignment_statement_type;
103
104 typedef struct lang_target_statement_struct
105 {
106 lang_statement_header_type header;
107 const char *target;
108 } lang_target_statement_type;
109
110 typedef struct lang_output_statement_struct
111 {
112 lang_statement_header_type header;
113 const char *name;
114 } lang_output_statement_type;
115
116 /* Section types specified in a linker script. */
117
118 enum section_type
119 {
120 normal_section,
121 first_overlay_section,
122 overlay_section,
123 noload_section,
124 noalloc_section,
125 type_section,
126 readonly_section,
127 typed_readonly_section
128 };
129
130 /* This structure holds a list of program headers describing
131 segments in which this section should be placed. */
132
133 typedef struct lang_output_section_phdr_list
134 {
135 struct lang_output_section_phdr_list *next;
136 const char *name;
137 bool used;
138 } lang_output_section_phdr_list;
139
140 typedef struct lang_output_section_statement_struct
141 {
142 lang_statement_header_type header;
143 lang_statement_list_type children;
144 struct lang_output_section_statement_struct *next;
145 struct lang_output_section_statement_struct *prev;
146 const char *name;
147 asection *bfd_section;
148 lang_memory_region_type *region;
149 lang_memory_region_type *lma_region;
150 fill_type *fill;
151 union etree_union *addr_tree;
152 union etree_union *load_base;
153 union etree_union *section_alignment;
154 union etree_union *subsection_alignment;
155
156 /* If non-null, an expression to evaluate after setting the section's
157 size. The expression is evaluated inside REGION (above) with '.'
158 set to the end of the section. Used in the last overlay section
159 to move '.' past all the overlaid sections. */
160 union etree_union *update_dot_tree;
161
162 lang_output_section_phdr_list *phdrs;
163
164 /* Used by ELF SHF_LINK_ORDER sorting. */
165 void *data;
166
167 unsigned int block_value;
168 int constraint;
169 flagword flags;
170 enum section_type sectype;
171 etree_type *sectype_value;
172 unsigned int processed_vma : 1;
173 unsigned int processed_lma : 1;
174 unsigned int all_input_readonly : 1;
175 /* If this section should be ignored. */
176 unsigned int ignored : 1;
177 /* If this section should update "dot". Prevents section being ignored. */
178 unsigned int update_dot : 1;
179 /* If this section is after assignment to _end. */
180 unsigned int after_end : 1;
181 /* If this section uses the alignment of its input sections. */
182 unsigned int align_lma_with_input : 1;
183 /* If script has duplicate output section statements of the same name
184 create duplicate output sections. */
185 unsigned int dup_output : 1;
186 } lang_output_section_statement_type;
187
188 typedef struct
189 {
190 lang_statement_header_type header;
191 fill_type *fill;
192 int size;
193 asection *output_section;
194 } lang_fill_statement_type;
195
196 typedef struct
197 {
198 lang_statement_header_type header;
199 unsigned int type;
200 union etree_union *exp;
201 bfd_vma value;
202 asection *output_section;
203 bfd_vma output_offset;
204 } lang_data_statement_type;
205
206 /* Generate a reloc in the output file. */
207
208 typedef struct
209 {
210 lang_statement_header_type header;
211
212 /* Reloc to generate. */
213 bfd_reloc_code_real_type reloc;
214
215 /* Reloc howto structure. */
216 reloc_howto_type *howto;
217
218 /* Section to generate reloc against.
219 Exactly one of section and name must be NULL. */
220 asection *section;
221
222 /* Name of symbol to generate reloc against.
223 Exactly one of section and name must be NULL. */
224 const char *name;
225
226 /* Expression for addend. */
227 union etree_union *addend_exp;
228
229 /* Resolved addend. */
230 bfd_vma addend_value;
231
232 /* Output section where reloc should be performed. */
233 asection *output_section;
234
235 /* Offset within output section. */
236 bfd_vma output_offset;
237 } lang_reloc_statement_type;
238
239 struct lang_input_statement_flags
240 {
241 /* 1 means this file was specified in a -l option. */
242 unsigned int maybe_archive : 1;
243
244 /* 1 means this file was specified in a -l:namespec option. */
245 unsigned int full_name_provided : 1;
246
247 /* 1 means search a set of directories for this file. */
248 unsigned int search_dirs : 1;
249
250 /* 1 means this was found when processing a script in the sysroot. */
251 unsigned int sysrooted : 1;
252
253 /* 1 means this is base file of incremental load.
254 Do not load this file's text or data.
255 Also default text_start to after this file's bss. */
256 unsigned int just_syms : 1;
257
258 /* Whether to search for this entry as a dynamic archive. */
259 unsigned int dynamic : 1;
260
261 /* Set if a DT_NEEDED tag should be added not just for the dynamic library
262 explicitly given by this entry but also for any dynamic libraries in
263 this entry's needed list. */
264 unsigned int add_DT_NEEDED_for_dynamic : 1;
265
266 /* Set if this entry should cause a DT_NEEDED tag only when some
267 regular file references its symbols (ie. --as-needed is in effect). */
268 unsigned int add_DT_NEEDED_for_regular : 1;
269
270 /* Whether to include the entire contents of an archive. */
271 unsigned int whole_archive : 1;
272
273 /* Set when bfd opening is successful. */
274 unsigned int loaded : 1;
275
276 unsigned int real : 1;
277
278 /* Set if the file does not exist. */
279 unsigned int missing_file : 1;
280
281 /* Set if reloading an archive or --as-needed lib. */
282 unsigned int reload : 1;
283
284 #if BFD_SUPPORTS_PLUGINS
285 /* Set if the file was claimed by a plugin. */
286 unsigned int claimed : 1;
287
288 /* Set if the file was claimed from an archive. */
289 unsigned int claim_archive : 1;
290
291 /* Set if added by the lto plugin add_input_file callback. */
292 unsigned int lto_output : 1;
293 #endif /* BFD_SUPPORTS_PLUGINS */
294
295 /* Head of list of pushed flags. */
296 struct lang_input_statement_flags *pushed;
297 };
298
299 typedef struct lang_input_statement_struct
300 {
301 lang_statement_header_type header;
302 /* Name of this file. */
303 const char *filename;
304 /* Name to use for the symbol giving address of text start.
305 Usually the same as filename, but for a file spec'd with
306 -l this is the -l switch itself rather than the filename. */
307 const char *local_sym_name;
308 /* Extra search path. Used to find a file relative to the
309 directory of the current linker script. */
310 const char *extra_search_path;
311
312 bfd *the_bfd;
313
314 ctf_archive_t *the_ctf;
315
316 struct flag_info *section_flag_list;
317
318 /* Next pointer for file_chain statement list. */
319 struct lang_input_statement_struct *next;
320
321 /* Next pointer for input_file_chain statement list. */
322 struct lang_input_statement_struct *next_real_file;
323
324 const char *target;
325
326 struct lang_input_statement_flags flags;
327 } lang_input_statement_type;
328
329 typedef struct
330 {
331 lang_statement_header_type header;
332 asection *section;
333 void *pattern;
334 } lang_input_section_type;
335
336 struct map_symbol_def {
337 struct bfd_link_hash_entry *entry;
338 struct map_symbol_def *next;
339 };
340
341 /* For input sections, when writing a map file: head / tail of a linked
342 list of hash table entries for symbols defined in this section. */
343 typedef struct input_section_userdata_struct
344 {
345 struct map_symbol_def *map_symbol_def_head;
346 struct map_symbol_def **map_symbol_def_tail;
347 unsigned long map_symbol_def_count;
348 } input_section_userdata_type;
349
350 static inline bool
bfd_input_just_syms(const bfd * abfd)351 bfd_input_just_syms (const bfd *abfd)
352 {
353 lang_input_statement_type *is = bfd_usrdata (abfd);
354 return is != NULL && is->flags.just_syms;
355 }
356
357 typedef struct lang_wild_statement_struct lang_wild_statement_type;
358
359 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
360 asection *, lang_input_statement_type *, void *);
361
362 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
363 lang_input_statement_type *,
364 callback_t callback,
365 void *data);
366
367 typedef bool (*lang_match_sec_type_func) (bfd *, const asection *,
368 bfd *, const asection *);
369
370 /* Binary search tree structure to efficiently sort sections by
371 name. */
372 typedef struct lang_section_bst
373 {
374 asection *section;
375 void *pattern;
376 struct lang_section_bst *left;
377 struct lang_section_bst *right;
378 } lang_section_bst_type;
379
380 struct lang_wild_statement_struct
381 {
382 lang_statement_header_type header;
383 const char *filename;
384 bool filenames_sorted;
385 struct wildcard_list *section_list;
386 bool keep_sections;
387 lang_statement_list_type children;
388 struct name_list *exclude_name_list;
389
390 walk_wild_section_handler_t walk_wild_section_handler;
391 struct wildcard_list *handler_data[4];
392 lang_section_bst_type *tree;
393 struct flag_info *section_flag_list;
394 };
395
396 typedef struct lang_address_statement_struct
397 {
398 lang_statement_header_type header;
399 const char *section_name;
400 union etree_union *address;
401 const segment_type *segment;
402 } lang_address_statement_type;
403
404 typedef struct
405 {
406 lang_statement_header_type header;
407 bfd_vma output_offset;
408 bfd_size_type size;
409 asection *output_section;
410 fill_type *fill;
411 } lang_padding_statement_type;
412
413 /* A group statement collects a set of libraries together. The
414 libraries are searched multiple times, until no new undefined
415 symbols are found. The effect is to search a group of libraries as
416 though they were a single library. */
417
418 typedef struct
419 {
420 lang_statement_header_type header;
421 lang_statement_list_type children;
422 } lang_group_statement_type;
423
424 typedef struct
425 {
426 lang_statement_header_type header;
427 const char *where;
428 bool is_before;
429 } lang_insert_statement_type;
430
431 typedef union lang_statement_union
432 {
433 lang_statement_header_type header;
434 lang_address_statement_type address_statement;
435 lang_assignment_statement_type assignment_statement;
436 lang_data_statement_type data_statement;
437 lang_fill_statement_type fill_statement;
438 lang_group_statement_type group_statement;
439 lang_input_section_type input_section;
440 lang_input_statement_type input_statement;
441 lang_insert_statement_type insert_statement;
442 lang_output_section_statement_type output_section_statement;
443 lang_output_statement_type output_statement;
444 lang_padding_statement_type padding_statement;
445 lang_reloc_statement_type reloc_statement;
446 lang_target_statement_type target_statement;
447 lang_wild_statement_type wild_statement;
448 } lang_statement_union_type;
449
450 /* This structure holds information about a program header, from the
451 PHDRS command in the linker script. */
452
453 struct lang_phdr
454 {
455 struct lang_phdr *next;
456 const char *name;
457 unsigned long type;
458 bool filehdr;
459 bool phdrs;
460 etree_type *at;
461 etree_type *flags;
462 };
463
464 /* This structure is used to hold a list of sections which may not
465 cross reference each other. */
466
467 typedef struct lang_nocrossref
468 {
469 struct lang_nocrossref *next;
470 const char *name;
471 } lang_nocrossref_type;
472
473 /* The list of nocrossref lists. */
474
475 struct lang_nocrossrefs
476 {
477 struct lang_nocrossrefs *next;
478 lang_nocrossref_type *list;
479 bool onlyfirst;
480 };
481
482 /* This structure is used to hold a list of input section names which
483 will not match an output section in the linker script. */
484
485 struct unique_sections
486 {
487 struct unique_sections *next;
488 const char *name;
489 };
490
491 /* Used by place_orphan to keep track of orphan sections and statements. */
492
493 struct orphan_save
494 {
495 const char *name;
496 flagword flags;
497 lang_output_section_statement_type *os;
498 asection **section;
499 lang_statement_union_type **stmt;
500 lang_output_section_statement_type **os_tail;
501 };
502
503 struct asneeded_minfo
504 {
505 struct asneeded_minfo *next;
506 const char *soname;
507 bfd *ref;
508 const char *name;
509 };
510
511 extern struct lang_phdr *lang_phdr_list;
512 extern struct lang_nocrossrefs *nocrossref_list;
513 extern const char *output_target;
514 extern lang_output_section_statement_type *abs_output_section;
515 extern lang_statement_list_type lang_os_list;
516 extern struct lang_input_statement_flags input_flags;
517 extern bool lang_has_input_file;
518 extern lang_statement_list_type statement_list;
519 extern lang_statement_list_type *stat_ptr;
520 extern bool delete_output_file_on_failure;
521
522 extern struct bfd_sym_chain entry_symbol;
523 extern const char *entry_section;
524 extern bool entry_from_cmdline;
525 extern lang_statement_list_type file_chain;
526 extern lang_statement_list_type input_file_chain;
527
528 extern struct bfd_elf_dynamic_list **current_dynamic_list_p;
529
530 extern int lang_statement_iteration;
531 extern struct asneeded_minfo **asneeded_list_tail;
532
533 extern void (*output_bfd_hash_table_free_fn) (struct bfd_link_hash_table *);
534
535 extern void lang_init
536 (void);
537 extern void lang_finish
538 (void);
539 extern lang_memory_region_type * lang_memory_region_lookup
540 (const char * const, bool);
541 extern void lang_memory_region_alias
542 (const char *, const char *);
543 extern void lang_map
544 (void);
545 extern void lang_set_flags
546 (lang_memory_region_type *, const char *, int);
547 extern void lang_add_output
548 (const char *, int from_script);
549 extern lang_output_section_statement_type *lang_enter_output_section_statement
550 (const char *, etree_type *, enum section_type, etree_type *, etree_type *,
551 etree_type *, etree_type *, int, int);
552 extern void lang_final
553 (void);
554 extern void lang_relax_sections
555 (bool);
556 extern void lang_process
557 (void);
558 extern void lang_section_start
559 (const char *, union etree_union *, const segment_type *);
560 extern void lang_add_entry
561 (const char *, bool);
562 extern void lang_default_entry
563 (const char *);
564 extern void lang_add_target
565 (const char *);
566 extern void lang_add_wild
567 (struct wildcard_spec *, struct wildcard_list *, bool);
568 extern void lang_add_map
569 (const char *);
570 extern void lang_add_fill
571 (fill_type *);
572 extern lang_assignment_statement_type *lang_add_assignment
573 (union etree_union *);
574 extern void lang_add_attribute
575 (enum statement_enum);
576 extern void lang_startup
577 (const char *);
578 extern void lang_float
579 (bool);
580 extern void lang_leave_output_section_statement
581 (fill_type *, const char *, lang_output_section_phdr_list *,
582 const char *);
583 extern void lang_for_each_input_file
584 (void (*dothis) (lang_input_statement_type *));
585 extern void lang_for_each_file
586 (void (*dothis) (lang_input_statement_type *));
587 extern void lang_reset_memory_regions
588 (void);
589 extern void lang_do_assignments
590 (lang_phase_type);
591 extern asection *section_for_dot
592 (void);
593
594 #define LANG_FOR_EACH_INPUT_STATEMENT(statement) \
595 lang_input_statement_type *statement; \
596 for (statement = (lang_input_statement_type *) file_chain.head; \
597 statement != NULL; \
598 statement = statement->next)
599
600 #define lang_output_section_find(NAME) \
601 lang_output_section_statement_lookup (NAME, 0, 0)
602
603 extern void lang_process
604 (void);
605 extern void ldlang_add_file
606 (lang_input_statement_type *);
607 extern lang_output_section_statement_type *lang_output_section_find_by_flags
608 (const asection *, flagword, lang_output_section_statement_type **,
609 lang_match_sec_type_func);
610 extern lang_output_section_statement_type *lang_insert_orphan
611 (asection *, const char *, int, lang_output_section_statement_type *,
612 struct orphan_save *, etree_type *, lang_statement_list_type *);
613 extern lang_input_statement_type *lang_add_input_file
614 (const char *, lang_input_file_enum_type, const char *);
615 extern void lang_add_keepsyms_file
616 (const char *);
617 extern lang_output_section_statement_type *lang_output_section_get
618 (const asection *);
619 extern lang_output_section_statement_type *lang_output_section_statement_lookup
620 (const char *, int, int);
621 extern lang_output_section_statement_type *next_matching_output_section_statement
622 (lang_output_section_statement_type *, int);
623 extern void ldlang_add_undef
624 (const char *const, bool);
625 extern void ldlang_add_require_defined
626 (const char *const);
627 extern void lang_add_output_format
628 (const char *, const char *, const char *, int);
629 extern void lang_list_init
630 (lang_statement_list_type *);
631 extern void push_stat_ptr
632 (lang_statement_list_type *);
633 extern void pop_stat_ptr
634 (void);
635 extern void lang_add_data
636 (int type, union etree_union *);
637 extern void lang_add_reloc
638 (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
639 union etree_union *);
640 extern void lang_for_each_statement
641 (void (*) (lang_statement_union_type *));
642 extern void lang_for_each_statement_worker
643 (void (*) (lang_statement_union_type *), lang_statement_union_type *);
644 extern void *stat_alloc
645 (size_t);
646 extern void strip_excluded_output_sections
647 (void);
648 extern void lang_clear_os_map
649 (void);
650 extern void dprint_statement
651 (lang_statement_union_type *, int);
652 extern void lang_size_sections
653 (bool *, bool);
654 extern void one_lang_size_sections_pass
655 (bool *, bool);
656 extern void lang_add_insert
657 (const char *, int);
658 extern void lang_enter_group
659 (void);
660 extern void lang_leave_group
661 (void);
662 extern void lang_add_section
663 (lang_statement_list_type *, asection *, struct wildcard_list *,
664 struct flag_info *, lang_output_section_statement_type *);
665 extern void lang_new_phdr
666 (const char *, etree_type *, bool, bool, etree_type *,
667 etree_type *);
668 extern void lang_add_nocrossref
669 (lang_nocrossref_type *);
670 extern void lang_add_nocrossref_to
671 (lang_nocrossref_type *);
672 extern void lang_enter_overlay
673 (etree_type *, etree_type *);
674 extern void lang_enter_overlay_section
675 (const char *);
676 extern void lang_leave_overlay_section
677 (fill_type *, lang_output_section_phdr_list *);
678 extern void lang_leave_overlay
679 (etree_type *, int, fill_type *, const char *,
680 lang_output_section_phdr_list *, const char *);
681
682 extern struct bfd_elf_version_expr *lang_new_vers_pattern
683 (struct bfd_elf_version_expr *, const char *, const char *, bool);
684 extern struct bfd_elf_version_tree *lang_new_vers_node
685 (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
686 extern struct bfd_elf_version_deps *lang_add_vers_depend
687 (struct bfd_elf_version_deps *, const char *);
688 extern void lang_register_vers_node
689 (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
690 extern void lang_append_dynamic_list (struct bfd_elf_dynamic_list **,
691 struct bfd_elf_version_expr *);
692 extern void lang_append_dynamic_list_cpp_typeinfo (void);
693 extern void lang_append_dynamic_list_cpp_new (void);
694 extern void lang_add_unique
695 (const char *);
696 extern const char *lang_get_output_target
697 (void);
698 extern void add_excluded_libs (const char *);
699 extern bool load_symbols
700 (lang_input_statement_type *, lang_statement_list_type *);
701
702 struct elf_sym_strtab;
703 struct elf_strtab_hash;
704 extern void ldlang_ctf_acquire_strings
705 (struct elf_strtab_hash *);
706 extern void ldlang_ctf_new_dynsym
707 (int symidx, struct elf_internal_sym *);
708 extern void ldlang_write_ctf_late
709 (void);
710 extern bool
711 ldlang_override_segment_assignment
712 (struct bfd_link_info *, bfd *, asection *, asection *, bool);
713
714 extern void
715 lang_ld_feature (char *);
716
717 extern void
718 lang_print_memory_usage (void);
719
720 extern void
721 lang_add_gc_name (const char *);
722
723 extern bool
724 print_one_symbol (struct bfd_link_hash_entry *hash_entry, void *ptr);
725
726 #endif
727