1/* ldlang.h - linker command language support
2   Copyright (C) 1991-2017 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
26typedef enum
27{
28  lang_input_file_is_l_enum,
29  lang_input_file_is_symbols_only_enum,
30  lang_input_file_is_marker_enum,
31  lang_input_file_is_fake_enum,
32  lang_input_file_is_search_file_enum,
33  lang_input_file_is_file_enum
34} lang_input_file_enum_type;
35
36struct _fill_type
37{
38  size_t size;
39  unsigned char data[1];
40};
41
42typedef struct statement_list
43{
44  union lang_statement_union *  head;
45  union lang_statement_union ** tail;
46} lang_statement_list_type;
47
48typedef struct memory_region_name_struct
49{
50  const char * name;
51  struct memory_region_name_struct * next;
52} lang_memory_region_name;
53
54typedef struct memory_region_struct
55{
56  lang_memory_region_name name_list;
57  struct memory_region_struct *next;
58  union etree_union *origin_exp;
59  bfd_vma origin;
60  bfd_size_type length;
61  union etree_union *length_exp;
62  bfd_vma current;
63  union lang_statement_union *last_os;
64  flagword flags;
65  flagword not_flags;
66  bfd_boolean had_full_message;
67} lang_memory_region_type;
68
69enum statement_enum
70{
71  lang_output_section_statement_enum,
72  lang_assignment_statement_enum,
73  lang_input_statement_enum,
74  lang_address_statement_enum,
75  lang_wild_statement_enum,
76  lang_input_section_enum,
77  lang_object_symbols_statement_enum,
78  lang_fill_statement_enum,
79  lang_data_statement_enum,
80  lang_reloc_statement_enum,
81  lang_target_statement_enum,
82  lang_output_statement_enum,
83  lang_padding_statement_enum,
84  lang_group_statement_enum,
85  lang_insert_statement_enum,
86  lang_constructors_statement_enum
87};
88
89typedef struct lang_statement_header_struct
90{
91  union lang_statement_union *next;
92  enum statement_enum type;
93} lang_statement_header_type;
94
95typedef struct
96{
97  lang_statement_header_type header;
98  union etree_union *exp;
99} lang_assignment_statement_type;
100
101typedef struct lang_target_statement_struct
102{
103  lang_statement_header_type header;
104  const char *target;
105} lang_target_statement_type;
106
107typedef struct lang_output_statement_struct
108{
109  lang_statement_header_type header;
110  const char *name;
111} lang_output_statement_type;
112
113/* Section types specified in a linker script.  */
114
115enum section_type
116{
117  normal_section,
118  overlay_section,
119  noload_section,
120  noalloc_section
121};
122
123/* This structure holds a list of program headers describing
124   segments in which this section should be placed.  */
125
126typedef struct lang_output_section_phdr_list
127{
128  struct lang_output_section_phdr_list *next;
129  const char *name;
130  bfd_boolean used;
131} lang_output_section_phdr_list;
132
133typedef struct lang_output_section_statement_struct
134{
135  lang_statement_header_type header;
136  lang_statement_list_type children;
137  struct lang_output_section_statement_struct *next;
138  struct lang_output_section_statement_struct *prev;
139  const char *name;
140  asection *bfd_section;
141  lang_memory_region_type *region;
142  lang_memory_region_type *lma_region;
143  fill_type *fill;
144  union etree_union *addr_tree;
145  union etree_union *load_base;
146
147  /* If non-null, an expression to evaluate after setting the section's
148     size.  The expression is evaluated inside REGION (above) with '.'
149     set to the end of the section.  Used in the last overlay section
150     to move '.' past all the overlaid sections.  */
151  union etree_union *update_dot_tree;
152
153  lang_output_section_phdr_list *phdrs;
154
155  unsigned int block_value;
156  int subsection_alignment;	/* Alignment of components.  */
157  int section_alignment;	/* Alignment of start of section.  */
158  int constraint;
159  flagword flags;
160  enum section_type sectype;
161  unsigned int processed_vma : 1;
162  unsigned int processed_lma : 1;
163  unsigned int all_input_readonly : 1;
164  /* If this section should be ignored.  */
165  unsigned int ignored : 1;
166  /* If this section should update "dot".  Prevents section being ignored.  */
167  unsigned int update_dot : 1;
168  /* If this section is after assignment to _end.  */
169  unsigned int after_end : 1;
170  /* If this section uses the alignment of its input sections.  */
171  unsigned int align_lma_with_input : 1;
172} lang_output_section_statement_type;
173
174typedef struct
175{
176  lang_statement_header_type header;
177} lang_common_statement_type;
178
179typedef struct
180{
181  lang_statement_header_type header;
182} lang_object_symbols_statement_type;
183
184typedef struct
185{
186  lang_statement_header_type header;
187  fill_type *fill;
188  int size;
189  asection *output_section;
190} lang_fill_statement_type;
191
192typedef struct
193{
194  lang_statement_header_type header;
195  unsigned int type;
196  union etree_union *exp;
197  bfd_vma value;
198  asection *output_section;
199  bfd_vma output_offset;
200} lang_data_statement_type;
201
202/* Generate a reloc in the output file.  */
203
204typedef struct
205{
206  lang_statement_header_type header;
207
208  /* Reloc to generate.  */
209  bfd_reloc_code_real_type reloc;
210
211  /* Reloc howto structure.  */
212  reloc_howto_type *howto;
213
214  /* Section to generate reloc against.
215     Exactly one of section and name must be NULL.  */
216  asection *section;
217
218  /* Name of symbol to generate reloc against.
219     Exactly one of section and name must be NULL.  */
220  const char *name;
221
222  /* Expression for addend.  */
223  union etree_union *addend_exp;
224
225  /* Resolved addend.  */
226  bfd_vma addend_value;
227
228  /* Output section where reloc should be performed.  */
229  asection *output_section;
230
231  /* Offset within output section.  */
232  bfd_vma output_offset;
233} lang_reloc_statement_type;
234
235struct lang_input_statement_flags
236{
237  /* 1 means this file was specified in a -l option.  */
238  unsigned int maybe_archive : 1;
239
240  /* 1 means this file was specified in a -l:namespec option.  */
241  unsigned int full_name_provided : 1;
242
243  /* 1 means search a set of directories for this file.  */
244  unsigned int search_dirs : 1;
245
246  /* 1 means this was found when processing a script in the sysroot.  */
247  unsigned int sysrooted : 1;
248
249  /* 1 means this is base file of incremental load.
250     Do not load this file's text or data.
251     Also default text_start to after this file's bss.  */
252  unsigned int just_syms : 1;
253
254  /* Whether to search for this entry as a dynamic archive.  */
255  unsigned int dynamic : 1;
256
257  /* Set if a DT_NEEDED tag should be added not just for the dynamic library
258     explicitly given by this entry but also for any dynamic libraries in
259     this entry's needed list.  */
260  unsigned int add_DT_NEEDED_for_dynamic : 1;
261
262  /* Set if this entry should cause a DT_NEEDED tag only when some
263     regular file references its symbols (ie. --as-needed is in effect).  */
264  unsigned int add_DT_NEEDED_for_regular : 1;
265
266  /* Whether to include the entire contents of an archive.  */
267  unsigned int whole_archive : 1;
268
269  /* Set when bfd opening is successful.  */
270  unsigned int loaded : 1;
271
272  unsigned int real : 1;
273
274  /* Set if the file does not exist.  */
275  unsigned int missing_file : 1;
276
277  /* Set if reloading an archive or --as-needed lib.  */
278  unsigned int reload : 1;
279
280#ifdef ENABLE_PLUGINS
281  /* Set if the file was claimed by a plugin.  */
282  unsigned int claimed : 1;
283
284  /* Set if the file was claimed from an archive.  */
285  unsigned int claim_archive : 1;
286
287  /* Set if added by the lto plugin add_input_file callback.  */
288  unsigned int lto_output : 1;
289#endif /* ENABLE_PLUGINS */
290
291  /* Head of list of pushed flags.  */
292  struct lang_input_statement_flags *pushed;
293};
294
295typedef struct lang_input_statement_struct
296{
297  lang_statement_header_type header;
298  /* Name of this file.  */
299  const char *filename;
300  /* Name to use for the symbol giving address of text start.
301     Usually the same as filename, but for a file spec'd with
302     -l this is the -l switch itself rather than the filename.  */
303  const char *local_sym_name;
304
305  bfd *the_bfd;
306
307  struct flag_info *section_flag_list;
308
309  /* Point to the next file - whatever it is, wanders up and down
310     archives */
311  union lang_statement_union *next;
312
313  /* Point to the next file, but skips archive contents.  */
314  union lang_statement_union *next_real_file;
315
316  const char *target;
317
318  struct lang_input_statement_flags flags;
319} lang_input_statement_type;
320
321typedef struct
322{
323  lang_statement_header_type header;
324  asection *section;
325} lang_input_section_type;
326
327struct map_symbol_def {
328  struct bfd_link_hash_entry *entry;
329  struct map_symbol_def *next;
330};
331
332/* For input sections, when writing a map file: head / tail of a linked
333   list of hash table entries for symbols defined in this section.  */
334typedef struct input_section_userdata_struct
335{
336  struct map_symbol_def *map_symbol_def_head;
337  struct map_symbol_def **map_symbol_def_tail;
338  unsigned long map_symbol_def_count;
339} input_section_userdata_type;
340
341#define get_userdata(x) ((x)->userdata)
342
343
344typedef struct lang_wild_statement_struct lang_wild_statement_type;
345
346typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
347			    asection *, struct flag_info *,
348			    lang_input_statement_type *, void *);
349
350typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
351					     lang_input_statement_type *,
352					     callback_t callback,
353					     void *data);
354
355typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
356						 bfd *, const asection *);
357
358/* Binary search tree structure to efficiently sort sections by
359   name.  */
360typedef struct lang_section_bst
361{
362  asection *section;
363  struct lang_section_bst *left;
364  struct lang_section_bst *right;
365} lang_section_bst_type;
366
367struct lang_wild_statement_struct
368{
369  lang_statement_header_type header;
370  const char *filename;
371  bfd_boolean filenames_sorted;
372  struct wildcard_list *section_list;
373  bfd_boolean keep_sections;
374  lang_statement_list_type children;
375  struct name_list *exclude_name_list;
376
377  walk_wild_section_handler_t walk_wild_section_handler;
378  struct wildcard_list *handler_data[4];
379  lang_section_bst_type *tree;
380  struct flag_info *section_flag_list;
381};
382
383typedef struct lang_address_statement_struct
384{
385  lang_statement_header_type header;
386  const char *section_name;
387  union etree_union *address;
388  const segment_type *segment;
389} lang_address_statement_type;
390
391typedef struct
392{
393  lang_statement_header_type header;
394  bfd_vma output_offset;
395  bfd_size_type size;
396  asection *output_section;
397  fill_type *fill;
398} lang_padding_statement_type;
399
400/* A group statement collects a set of libraries together.  The
401   libraries are searched multiple times, until no new undefined
402   symbols are found.  The effect is to search a group of libraries as
403   though they were a single library.  */
404
405typedef struct
406{
407  lang_statement_header_type header;
408  lang_statement_list_type children;
409} lang_group_statement_type;
410
411typedef struct
412{
413  lang_statement_header_type header;
414  const char *where;
415  bfd_boolean is_before;
416} lang_insert_statement_type;
417
418typedef union lang_statement_union
419{
420  lang_statement_header_type header;
421  lang_wild_statement_type wild_statement;
422  lang_data_statement_type data_statement;
423  lang_reloc_statement_type reloc_statement;
424  lang_address_statement_type address_statement;
425  lang_output_section_statement_type output_section_statement;
426  lang_assignment_statement_type assignment_statement;
427  lang_input_statement_type input_statement;
428  lang_target_statement_type target_statement;
429  lang_output_statement_type output_statement;
430  lang_input_section_type input_section;
431  lang_common_statement_type common_statement;
432  lang_object_symbols_statement_type object_symbols_statement;
433  lang_fill_statement_type fill_statement;
434  lang_padding_statement_type padding_statement;
435  lang_group_statement_type group_statement;
436  lang_insert_statement_type insert_statement;
437} lang_statement_union_type;
438
439/* This structure holds information about a program header, from the
440   PHDRS command in the linker script.  */
441
442struct lang_phdr
443{
444  struct lang_phdr *next;
445  const char *name;
446  unsigned long type;
447  bfd_boolean filehdr;
448  bfd_boolean phdrs;
449  etree_type *at;
450  etree_type *flags;
451};
452
453/* This structure is used to hold a list of sections which may not
454   cross reference each other.  */
455
456typedef struct lang_nocrossref
457{
458  struct lang_nocrossref *next;
459  const char *name;
460} lang_nocrossref_type;
461
462/* The list of nocrossref lists.  */
463
464struct lang_nocrossrefs
465{
466  struct lang_nocrossrefs *next;
467  lang_nocrossref_type *list;
468  bfd_boolean onlyfirst;
469};
470
471/* This structure is used to hold a list of input section names which
472   will not match an output section in the linker script.  */
473
474struct unique_sections
475{
476  struct unique_sections *next;
477  const char *name;
478};
479
480/* Used by place_orphan to keep track of orphan sections and statements.  */
481
482struct orphan_save
483{
484  const char *name;
485  flagword flags;
486  lang_output_section_statement_type *os;
487  asection **section;
488  lang_statement_union_type **stmt;
489  lang_output_section_statement_type **os_tail;
490};
491
492struct asneeded_minfo
493{
494  struct asneeded_minfo *next;
495  const char *soname;
496  bfd *ref;
497  const char *name;
498};
499
500extern struct lang_phdr *lang_phdr_list;
501extern struct lang_nocrossrefs *nocrossref_list;
502extern const char *output_target;
503extern lang_output_section_statement_type *abs_output_section;
504extern lang_statement_list_type lang_output_section_statement;
505extern struct lang_input_statement_flags input_flags;
506extern bfd_boolean lang_has_input_file;
507extern lang_statement_list_type *stat_ptr;
508extern bfd_boolean delete_output_file_on_failure;
509
510extern struct bfd_sym_chain entry_symbol;
511extern const char *entry_section;
512extern bfd_boolean entry_from_cmdline;
513extern lang_statement_list_type file_chain;
514extern lang_statement_list_type input_file_chain;
515
516extern int lang_statement_iteration;
517extern struct asneeded_minfo **asneeded_list_tail;
518
519extern void (*output_bfd_hash_table_free_fn) (struct bfd_link_hash_table *);
520
521extern void lang_init
522  (void);
523extern void lang_finish
524  (void);
525extern lang_memory_region_type * lang_memory_region_lookup
526  (const char * const, bfd_boolean);
527extern void lang_memory_region_alias
528  (const char *, const char *);
529extern void lang_map
530  (void);
531extern void lang_set_flags
532  (lang_memory_region_type *, const char *, int);
533extern void lang_add_output
534  (const char *, int from_script);
535extern lang_output_section_statement_type *lang_enter_output_section_statement
536  (const char *, etree_type *, enum section_type, etree_type *, etree_type *,
537   etree_type *, int, int);
538extern void lang_final
539  (void);
540extern void lang_relax_sections
541  (bfd_boolean);
542extern void lang_process
543  (void);
544extern void lang_section_start
545  (const char *, union etree_union *, const segment_type *);
546extern void lang_add_entry
547  (const char *, bfd_boolean);
548extern void lang_default_entry
549  (const char *);
550extern void lang_add_target
551  (const char *);
552extern void lang_add_wild
553  (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
554extern void lang_add_map
555  (const char *);
556extern void lang_add_fill
557  (fill_type *);
558extern lang_assignment_statement_type *lang_add_assignment
559  (union etree_union *);
560extern void lang_add_attribute
561  (enum statement_enum);
562extern void lang_startup
563  (const char *);
564extern void lang_float
565  (bfd_boolean);
566extern void lang_leave_output_section_statement
567  (fill_type *, const char *, lang_output_section_phdr_list *,
568   const char *);
569extern void lang_statement_append
570  (lang_statement_list_type *, lang_statement_union_type *,
571   lang_statement_union_type **);
572extern void lang_for_each_input_file
573  (void (*dothis) (lang_input_statement_type *));
574extern void lang_for_each_file
575  (void (*dothis) (lang_input_statement_type *));
576extern void lang_reset_memory_regions
577  (void);
578extern void lang_do_assignments
579  (lang_phase_type);
580extern asection *section_for_dot
581  (void);
582
583#define LANG_FOR_EACH_INPUT_STATEMENT(statement)			\
584  lang_input_statement_type *statement;					\
585  for (statement = (lang_input_statement_type *) file_chain.head;	\
586       statement != (lang_input_statement_type *) NULL;			\
587       statement = (lang_input_statement_type *) statement->next)	\
588
589#define lang_output_section_find(NAME) \
590  lang_output_section_statement_lookup (NAME, 0, FALSE)
591
592extern void lang_process
593  (void);
594extern void ldlang_add_file
595  (lang_input_statement_type *);
596extern lang_output_section_statement_type *lang_output_section_find_by_flags
597  (const asection *, flagword, lang_output_section_statement_type **,
598   lang_match_sec_type_func);
599extern lang_output_section_statement_type *lang_insert_orphan
600  (asection *, const char *, int, lang_output_section_statement_type *,
601   struct orphan_save *, etree_type *, lang_statement_list_type *);
602extern lang_input_statement_type *lang_add_input_file
603  (const char *, lang_input_file_enum_type, const char *);
604extern void lang_add_keepsyms_file
605  (const char *);
606extern lang_output_section_statement_type *lang_output_section_get
607  (const asection *);
608extern lang_output_section_statement_type *lang_output_section_statement_lookup
609  (const char *, int, bfd_boolean);
610extern lang_output_section_statement_type *next_matching_output_section_statement
611  (lang_output_section_statement_type *, int);
612extern void ldlang_add_undef
613  (const char *const, bfd_boolean);
614extern void ldlang_add_require_defined
615  (const char *const);
616extern void lang_add_output_format
617  (const char *, const char *, const char *, int);
618extern void lang_list_init
619  (lang_statement_list_type *);
620extern void push_stat_ptr
621  (lang_statement_list_type *);
622extern void pop_stat_ptr
623  (void);
624extern void lang_add_data
625  (int type, union etree_union *);
626extern void lang_add_reloc
627  (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
628   union etree_union *);
629extern void lang_for_each_statement
630  (void (*) (lang_statement_union_type *));
631extern void lang_for_each_statement_worker
632  (void (*) (lang_statement_union_type *), lang_statement_union_type *);
633extern void *stat_alloc
634  (size_t);
635extern void strip_excluded_output_sections
636  (void);
637extern void lang_clear_os_map
638  (void);
639extern void dprint_statement
640  (lang_statement_union_type *, int);
641extern void lang_size_sections
642  (bfd_boolean *, bfd_boolean);
643extern void one_lang_size_sections_pass
644  (bfd_boolean *, bfd_boolean);
645extern void lang_add_insert
646  (const char *, int);
647extern void lang_enter_group
648  (void);
649extern void lang_leave_group
650  (void);
651extern void lang_add_section
652  (lang_statement_list_type *, asection *,
653   struct flag_info *, lang_output_section_statement_type *);
654extern void lang_new_phdr
655  (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
656   etree_type *);
657extern void lang_add_nocrossref
658  (lang_nocrossref_type *);
659extern void lang_add_nocrossref_to
660  (lang_nocrossref_type *);
661extern void lang_enter_overlay
662  (etree_type *, etree_type *);
663extern void lang_enter_overlay_section
664  (const char *);
665extern void lang_leave_overlay_section
666  (fill_type *, lang_output_section_phdr_list *);
667extern void lang_leave_overlay
668  (etree_type *, int, fill_type *, const char *,
669   lang_output_section_phdr_list *, const char *);
670
671extern struct bfd_elf_version_expr *lang_new_vers_pattern
672  (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
673extern struct bfd_elf_version_tree *lang_new_vers_node
674  (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
675extern struct bfd_elf_version_deps *lang_add_vers_depend
676  (struct bfd_elf_version_deps *, const char *);
677extern void lang_register_vers_node
678  (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
679extern void lang_append_dynamic_list (struct bfd_elf_version_expr *);
680extern void lang_append_dynamic_list_cpp_typeinfo (void);
681extern void lang_append_dynamic_list_cpp_new (void);
682extern void lang_add_unique
683  (const char *);
684extern const char *lang_get_output_target
685  (void);
686extern void add_excluded_libs (const char *);
687extern bfd_boolean load_symbols
688  (lang_input_statement_type *, lang_statement_list_type *);
689
690extern bfd_boolean
691ldlang_override_segment_assignment
692  (struct bfd_link_info *, bfd *, asection *, asection *, bfd_boolean);
693
694extern void
695lang_ld_feature (char *);
696
697extern void
698lang_print_memory_usage (void);
699
700extern void
701lang_add_gc_name (const char *);
702
703#endif
704