1 /* ldlang.h - linker command language support
2 Copyright (C) 1991-2024 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_matcher_enum,
80 lang_input_statement_enum,
81 lang_insert_statement_enum,
82 lang_output_section_statement_enum,
83 lang_output_statement_enum,
84 lang_padding_statement_enum,
85 lang_reloc_statement_enum,
86 lang_target_statement_enum,
87 lang_wild_statement_enum,
88 lang_constructors_statement_enum,
89 lang_object_symbols_statement_enum
90 };
91
92 typedef struct lang_statement_header_struct
93 {
94 /* Next pointer for statement_list statement list. */
95 union lang_statement_union *next;
96 enum statement_enum type;
97 } lang_statement_header_type;
98
99 typedef struct
100 {
101 lang_statement_header_type header;
102 union etree_union *exp;
103 } lang_assignment_statement_type;
104
105 typedef struct lang_target_statement_struct
106 {
107 lang_statement_header_type header;
108 const char *target;
109 } lang_target_statement_type;
110
111 typedef struct lang_output_statement_struct
112 {
113 lang_statement_header_type header;
114 const char *name;
115 } lang_output_statement_type;
116
117 /* Section types specified in a linker script. */
118
119 enum section_type
120 {
121 normal_section,
122 first_overlay_section,
123 overlay_section,
124 noload_section,
125 noalloc_section,
126 type_section,
127 readonly_section,
128 typed_readonly_section
129 };
130
131 /* This structure holds a list of program headers describing
132 segments in which this section should be placed. */
133
134 typedef struct lang_output_section_phdr_list
135 {
136 struct lang_output_section_phdr_list *next;
137 const char *name;
138 bool used;
139 } lang_output_section_phdr_list;
140
141 typedef struct lang_output_section_statement_struct
142 {
143 lang_statement_header_type header;
144 lang_statement_list_type children;
145 struct lang_output_section_statement_struct *next;
146 struct lang_output_section_statement_struct *prev;
147 const char *name;
148 asection *bfd_section;
149 lang_memory_region_type *region;
150 lang_memory_region_type *lma_region;
151 fill_type *fill;
152 union etree_union *addr_tree;
153 union etree_union *load_base;
154 union etree_union *section_alignment;
155 union etree_union *subsection_alignment;
156
157 /* If non-null, an expression to evaluate after setting the section's
158 size. The expression is evaluated inside REGION (above) with '.'
159 set to the end of the section. Used in the last overlay section
160 to move '.' past all the overlaid sections. */
161 union etree_union *update_dot_tree;
162
163 lang_output_section_phdr_list *phdrs;
164
165 /* Used by ELF SHF_LINK_ORDER sorting. */
166 void *data;
167
168 unsigned int block_value;
169 int constraint;
170 flagword flags;
171 enum section_type sectype;
172 etree_type *sectype_value;
173 unsigned int processed_vma : 1;
174 unsigned int processed_lma : 1;
175 unsigned int all_input_readonly : 1;
176 /* If this section should be ignored. */
177 unsigned int ignored : 1;
178 /* If this section should update "dot". Prevents section being ignored. */
179 unsigned int update_dot : 1;
180 /* If this section is after assignment to _end. */
181 unsigned int after_end : 1;
182 /* If this section uses the alignment of its input sections. */
183 unsigned int align_lma_with_input : 1;
184 /* If script has duplicate output section statements of the same name
185 create duplicate output sections. */
186 unsigned int dup_output : 1;
187 } lang_output_section_statement_type;
188
189 typedef struct
190 {
191 lang_statement_header_type header;
192 fill_type *fill;
193 int size;
194 asection *output_section;
195 } lang_fill_statement_type;
196
197 typedef struct
198 {
199 lang_statement_header_type header;
200 unsigned int type;
201 union etree_union *exp;
202 bfd_vma value;
203 asection *output_section;
204 bfd_vma output_offset;
205 } lang_data_statement_type;
206
207 /* Generate a reloc in the output file. */
208
209 typedef struct
210 {
211 lang_statement_header_type header;
212
213 /* Reloc to generate. */
214 bfd_reloc_code_real_type reloc;
215
216 /* Reloc howto structure. */
217 reloc_howto_type *howto;
218
219 /* Section to generate reloc against.
220 Exactly one of section and name must be NULL. */
221 asection *section;
222
223 /* Name of symbol to generate reloc against.
224 Exactly one of section and name must be NULL. */
225 const char *name;
226
227 /* Expression for addend. */
228 union etree_union *addend_exp;
229
230 /* Resolved addend. */
231 bfd_vma addend_value;
232
233 /* Output section where reloc should be performed. */
234 asection *output_section;
235
236 /* Offset within output section. */
237 bfd_vma output_offset;
238 } lang_reloc_statement_type;
239
240 struct lang_input_statement_flags
241 {
242 /* 1 means this file was specified in a -l option. */
243 unsigned int maybe_archive : 1;
244
245 /* 1 means this file was specified in a -l:namespec option. */
246 unsigned int full_name_provided : 1;
247
248 /* 1 means search a set of directories for this file. */
249 unsigned int search_dirs : 1;
250
251 /* 1 means this was found when processing a script in the sysroot. */
252 unsigned int sysrooted : 1;
253
254 /* 1 means this is base file of incremental load.
255 Do not load this file's text or data.
256 Also default text_start to after this file's bss. */
257 unsigned int just_syms : 1;
258
259 /* Whether to search for this entry as a dynamic archive. */
260 unsigned int dynamic : 1;
261
262 /* Set if a DT_NEEDED tag should be added not just for the dynamic library
263 explicitly given by this entry but also for any dynamic libraries in
264 this entry's needed list. */
265 unsigned int add_DT_NEEDED_for_dynamic : 1;
266
267 /* Set if this entry should cause a DT_NEEDED tag only when some
268 regular file references its symbols (ie. --as-needed is in effect). */
269 unsigned int add_DT_NEEDED_for_regular : 1;
270
271 /* Whether to include the entire contents of an archive. */
272 unsigned int whole_archive : 1;
273
274 /* Set when bfd opening is successful. */
275 unsigned int loaded : 1;
276
277 unsigned int real : 1;
278
279 /* Set if the file does not exist. */
280 unsigned int missing_file : 1;
281
282 /* Set if reloading an archive or --as-needed lib. */
283 unsigned int reload : 1;
284
285 #if BFD_SUPPORTS_PLUGINS
286 /* Set if the file was claimed by a plugin. */
287 unsigned int claimed : 1;
288
289 /* Set if the file was claimed from an archive. */
290 unsigned int claim_archive : 1;
291
292 /* Set if added by the lto plugin add_input_file callback. */
293 unsigned int lto_output : 1;
294 #endif /* BFD_SUPPORTS_PLUGINS */
295
296 /* Head of list of pushed flags. */
297 struct lang_input_statement_flags *pushed;
298 };
299
300 typedef struct lang_input_statement_struct
301 {
302 lang_statement_header_type header;
303 /* Name of this file. */
304 const char *filename;
305 /* Name to use for the symbol giving address of text start.
306 Usually the same as filename, but for a file spec'd with
307 -l this is the -l switch itself rather than the filename. */
308 const char *local_sym_name;
309 /* Name to use when sorting. */
310 const char *sort_key;
311 /* Extra search path. Used to find a file relative to the
312 directory of the current linker script. */
313 const char *extra_search_path;
314
315 bfd *the_bfd;
316
317 ctf_archive_t *the_ctf;
318
319 struct flag_info *section_flag_list;
320
321 /* Next pointer for file_chain statement list. */
322 struct lang_input_statement_struct *next;
323
324 /* Next pointer for input_file_chain statement list. */
325 struct lang_input_statement_struct *next_real_file;
326
327 const char *target;
328
329 struct lang_input_statement_flags flags;
330 } lang_input_statement_type;
331
332 typedef struct
333 {
334 lang_statement_header_type header;
335 asection *section;
336 void *pattern;
337 } lang_input_section_type;
338
339 typedef struct
340 {
341 lang_statement_header_type header;
342 asection *section;
343 void *pattern;
344 lang_input_statement_type *input_stmt;
345 } lang_input_matcher_type;
346
347 struct map_symbol_def {
348 struct bfd_link_hash_entry *entry;
349 struct map_symbol_def *next;
350 };
351
352 /* For input sections, when writing a map file: head / tail of a linked
353 list of hash table entries for symbols defined in this section. */
354 typedef struct input_section_userdata_struct
355 {
356 struct map_symbol_def *map_symbol_def_head;
357 struct map_symbol_def **map_symbol_def_tail;
358 unsigned long map_symbol_def_count;
359 } input_section_userdata_type;
360
361 static inline bool
bfd_input_just_syms(const bfd * abfd)362 bfd_input_just_syms (const bfd *abfd)
363 {
364 lang_input_statement_type *is = bfd_usrdata (abfd);
365 return is != NULL && is->flags.just_syms;
366 }
367
368 typedef struct lang_wild_statement_struct lang_wild_statement_type;
369
370 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
371 asection *, lang_input_statement_type *, void *);
372
373 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
374 lang_input_statement_type *,
375 callback_t callback,
376 void *data);
377
378 typedef bool (*lang_match_sec_type_func) (bfd *, const asection *,
379 bfd *, const asection *);
380
381 /* Binary search tree structure to efficiently sort sections by
382 name. */
383 typedef struct lang_section_bst
384 {
385 asection *section;
386 void *pattern;
387 struct lang_section_bst *left;
388 struct lang_section_bst *right;
389 } lang_section_bst_type;
390
391 struct lang_wild_statement_struct
392 {
393 lang_statement_header_type header;
394 lang_statement_list_type children;
395 lang_statement_list_type matching_sections;
396 lang_section_bst_type * tree;
397 lang_section_bst_type ** rightmost;
398 struct wildcard_list * section_list;
399 struct name_list * exclude_name_list;
400 struct flag_info * section_flag_list;
401 const char * filename;
402 bool filenames_sorted;
403 bool filenames_reversed;
404 bool any_specs_sorted;
405 bool keep_sections;
406 };
407
408 typedef struct lang_address_statement_struct
409 {
410 lang_statement_header_type header;
411 const char *section_name;
412 union etree_union *address;
413 const segment_type *segment;
414 } lang_address_statement_type;
415
416 typedef struct
417 {
418 lang_statement_header_type header;
419 bfd_vma output_offset;
420 bfd_size_type size;
421 asection *output_section;
422 fill_type *fill;
423 } lang_padding_statement_type;
424
425 /* A group statement collects a set of libraries together. The
426 libraries are searched multiple times, until no new undefined
427 symbols are found. The effect is to search a group of libraries as
428 though they were a single library. */
429
430 typedef struct
431 {
432 lang_statement_header_type header;
433 lang_statement_list_type children;
434 } lang_group_statement_type;
435
436 typedef struct
437 {
438 lang_statement_header_type header;
439 const char *where;
440 bool is_before;
441 } lang_insert_statement_type;
442
443 typedef union lang_statement_union
444 {
445 lang_statement_header_type header;
446 lang_address_statement_type address_statement;
447 lang_assignment_statement_type assignment_statement;
448 lang_data_statement_type data_statement;
449 lang_fill_statement_type fill_statement;
450 lang_group_statement_type group_statement;
451 lang_input_section_type input_section;
452 lang_input_matcher_type input_matcher;
453 lang_input_statement_type input_statement;
454 lang_insert_statement_type insert_statement;
455 lang_output_section_statement_type output_section_statement;
456 lang_output_statement_type output_statement;
457 lang_padding_statement_type padding_statement;
458 lang_reloc_statement_type reloc_statement;
459 lang_target_statement_type target_statement;
460 lang_wild_statement_type wild_statement;
461 } lang_statement_union_type;
462
463 /* This structure holds information about a program header, from the
464 PHDRS command in the linker script. */
465
466 struct lang_phdr
467 {
468 struct lang_phdr *next;
469 const char *name;
470 unsigned long type;
471 bool filehdr;
472 bool phdrs;
473 etree_type *at;
474 etree_type *flags;
475 };
476
477 /* This structure is used to hold a list of sections which may not
478 cross reference each other. */
479
480 typedef struct lang_nocrossref
481 {
482 struct lang_nocrossref *next;
483 const char *name;
484 } lang_nocrossref_type;
485
486 /* The list of nocrossref lists. */
487
488 struct lang_nocrossrefs
489 {
490 struct lang_nocrossrefs *next;
491 lang_nocrossref_type *list;
492 bool onlyfirst;
493 };
494
495 /* This structure is used to hold a list of input section names which
496 will not match an output section in the linker script. */
497
498 struct unique_sections
499 {
500 struct unique_sections *next;
501 const char *name;
502 };
503
504 /* Used by place_orphan to keep track of orphan sections and statements. */
505
506 struct orphan_save
507 {
508 const char *name;
509 flagword flags;
510 lang_output_section_statement_type *os;
511 asection **section;
512 lang_statement_union_type **stmt;
513 lang_output_section_statement_type **os_tail;
514 };
515
516 struct asneeded_minfo
517 {
518 struct asneeded_minfo *next;
519 const char *soname;
520 bfd *ref;
521 const char *name;
522 };
523
524 extern struct lang_phdr *lang_phdr_list;
525 extern struct lang_nocrossrefs *nocrossref_list;
526 extern const char *output_target;
527 extern lang_output_section_statement_type *abs_output_section;
528 extern lang_statement_list_type lang_os_list;
529 extern struct lang_input_statement_flags input_flags;
530 extern bool lang_has_input_file;
531 extern lang_statement_list_type statement_list;
532 extern lang_statement_list_type *stat_ptr;
533 extern bool delete_output_file_on_failure;
534 extern bool enable_linker_version;
535
536 extern struct bfd_sym_chain entry_symbol;
537 extern const char *entry_section;
538 extern bool entry_from_cmdline;
539 extern lang_statement_list_type file_chain;
540 extern lang_statement_list_type input_file_chain;
541
542 extern struct bfd_elf_dynamic_list **current_dynamic_list_p;
543
544 extern int lang_statement_iteration;
545 extern struct asneeded_minfo **asneeded_list_tail;
546
547 extern void (*output_bfd_hash_table_free_fn) (struct bfd_link_hash_table *);
548
549 extern void lang_init
550 (void);
551 extern void lang_finish
552 (void);
553 extern lang_memory_region_type * lang_memory_region_lookup
554 (const char * const, bool);
555 extern void lang_memory_region_alias
556 (const char *, const char *);
557 extern void lang_map
558 (void);
559 extern void lang_set_flags
560 (lang_memory_region_type *, const char *, int);
561 extern void lang_add_output
562 (const char *, int from_script);
563 extern lang_output_section_statement_type *lang_enter_output_section_statement
564 (const char *, etree_type *, enum section_type, etree_type *, etree_type *,
565 etree_type *, etree_type *, int, int);
566 extern void lang_final
567 (void);
568 extern void lang_relax_sections
569 (bool);
570 extern void lang_process
571 (void);
572 extern void lang_section_start
573 (const char *, union etree_union *, const segment_type *);
574 extern void lang_add_entry
575 (const char *, bool);
576 extern void lang_default_entry
577 (const char *);
578 extern void lang_add_target
579 (const char *);
580 extern void lang_add_wild
581 (struct wildcard_spec *, struct wildcard_list *, bool);
582 extern void lang_add_map
583 (const char *);
584 extern void lang_add_fill
585 (fill_type *);
586 extern lang_assignment_statement_type *lang_add_assignment
587 (union etree_union *);
588 extern void lang_add_attribute
589 (enum statement_enum);
590 extern void lang_startup
591 (const char *);
592 extern void lang_float
593 (bool);
594 extern void lang_leave_output_section_statement
595 (fill_type *, const char *, lang_output_section_phdr_list *,
596 const char *);
597 extern void lang_for_each_input_file
598 (void (*dothis) (lang_input_statement_type *));
599 extern void lang_for_each_file
600 (void (*dothis) (lang_input_statement_type *));
601 extern void lang_reset_memory_regions
602 (void);
603 extern void lang_do_assignments
604 (lang_phase_type);
605 extern asection *section_for_dot
606 (void);
607
608 #define LANG_FOR_EACH_INPUT_STATEMENT(statement) \
609 lang_input_statement_type *statement; \
610 for (statement = (lang_input_statement_type *) file_chain.head; \
611 statement != NULL; \
612 statement = statement->next)
613
614 #define lang_output_section_find(NAME) \
615 lang_output_section_statement_lookup (NAME, 0, 0)
616
617 extern void lang_process
618 (void);
619 extern void ldlang_add_file
620 (lang_input_statement_type *);
621 extern lang_output_section_statement_type *lang_output_section_find_by_flags
622 (const asection *, flagword, lang_output_section_statement_type **,
623 lang_match_sec_type_func);
624 extern lang_output_section_statement_type *lang_insert_orphan
625 (asection *, const char *, int, lang_output_section_statement_type *,
626 struct orphan_save *, etree_type *, lang_statement_list_type *);
627 extern lang_input_statement_type *lang_add_input_file
628 (const char *, lang_input_file_enum_type, const char *);
629 extern void lang_add_keepsyms_file
630 (const char *);
631 extern lang_output_section_statement_type *lang_output_section_get
632 (const asection *);
633 extern lang_output_section_statement_type *lang_output_section_statement_lookup
634 (const char *, int, int);
635 extern lang_output_section_statement_type *next_matching_output_section_statement
636 (lang_output_section_statement_type *, int);
637 extern void ldlang_add_undef
638 (const char *const, bool);
639 extern void ldlang_add_require_defined
640 (const char *const);
641 extern void lang_add_output_format
642 (const char *, const char *, const char *, int);
643 extern void lang_list_init
644 (lang_statement_list_type *);
645 extern void push_stat_ptr
646 (lang_statement_list_type *);
647 extern void pop_stat_ptr
648 (void);
649 extern void lang_add_data
650 (int, union etree_union *);
651 extern void lang_add_string
652 (const char *);
653 extern void lang_add_reloc
654 (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
655 union etree_union *);
656 extern void lang_for_each_statement
657 (void (*) (lang_statement_union_type *));
658 extern void lang_for_each_statement_worker
659 (void (*) (lang_statement_union_type *), lang_statement_union_type *);
660 extern void *stat_alloc
661 (size_t);
662 extern void strip_excluded_output_sections
663 (void);
664 extern void lang_clear_os_map
665 (void);
666 extern void dprint_statement
667 (lang_statement_union_type *, int);
668 extern void lang_size_sections
669 (bool *, bool);
670 extern void one_lang_size_sections_pass
671 (bool *, bool);
672 extern void lang_add_insert
673 (const char *, int);
674 extern void lang_enter_group
675 (void);
676 extern void lang_leave_group
677 (void);
678 extern void lang_add_section
679 (lang_statement_list_type *, asection *, struct wildcard_list *,
680 struct flag_info *, lang_output_section_statement_type *);
681 extern void lang_new_phdr
682 (const char *, etree_type *, bool, bool, etree_type *,
683 etree_type *);
684 extern void lang_add_nocrossref
685 (lang_nocrossref_type *);
686 extern void lang_add_nocrossref_to
687 (lang_nocrossref_type *);
688 extern void lang_enter_overlay
689 (etree_type *, etree_type *);
690 extern void lang_enter_overlay_section
691 (const char *);
692 extern void lang_leave_overlay_section
693 (fill_type *, lang_output_section_phdr_list *);
694 extern void lang_leave_overlay
695 (etree_type *, int, fill_type *, const char *,
696 lang_output_section_phdr_list *, const char *);
697
698 extern struct bfd_elf_version_expr *lang_new_vers_pattern
699 (struct bfd_elf_version_expr *, const char *, const char *, bool);
700 extern struct bfd_elf_version_tree *lang_new_vers_node
701 (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
702 extern struct bfd_elf_version_deps *lang_add_vers_depend
703 (struct bfd_elf_version_deps *, const char *);
704 extern void lang_register_vers_node
705 (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
706 extern void lang_append_dynamic_list (struct bfd_elf_dynamic_list **,
707 struct bfd_elf_version_expr *);
708 extern void lang_append_dynamic_list_cpp_typeinfo (void);
709 extern void lang_append_dynamic_list_cpp_new (void);
710 extern void lang_add_unique
711 (const char *);
712 extern const char *lang_get_output_target
713 (void);
714 extern void add_excluded_libs (const char *);
715 extern bool load_symbols
716 (lang_input_statement_type *, lang_statement_list_type *);
717
718 struct elf_sym_strtab;
719 struct elf_strtab_hash;
720 extern void ldlang_ctf_acquire_strings
721 (struct elf_strtab_hash *);
722 extern void ldlang_ctf_new_dynsym
723 (int symidx, struct elf_internal_sym *);
724 extern void ldlang_write_ctf_late
725 (void);
726 extern bool
727 ldlang_override_segment_assignment
728 (struct bfd_link_info *, bfd *, asection *, asection *, bool);
729
730 extern void
731 lang_ld_feature (char *);
732
733 extern void
734 lang_print_memory_usage (void);
735
736 extern void
737 lang_add_gc_name (const char *);
738
739 extern bool
740 print_one_symbol (struct bfd_link_hash_entry *, void *);
741
742 extern void lang_add_version_string
743 (void);
744 #endif
745