1 /* ldlang.h - linker command language support 2 Copyright (C) 1991-2020 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 typedef 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 36 struct _fill_type 37 { 38 size_t size; 39 unsigned char data[1]; 40 }; 41 42 typedef struct statement_list 43 { 44 union lang_statement_union * head; 45 union lang_statement_union ** tail; 46 } lang_statement_list_type; 47 48 typedef struct memory_region_name_struct 49 { 50 const char * name; 51 struct memory_region_name_struct * next; 52 } lang_memory_region_name; 53 54 typedef 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 69 enum statement_enum 70 { 71 lang_address_statement_enum, 72 lang_assignment_statement_enum, 73 lang_data_statement_enum, 74 lang_fill_statement_enum, 75 lang_group_statement_enum, 76 lang_input_section_enum, 77 lang_input_statement_enum, 78 lang_insert_statement_enum, 79 lang_output_section_statement_enum, 80 lang_output_statement_enum, 81 lang_padding_statement_enum, 82 lang_reloc_statement_enum, 83 lang_target_statement_enum, 84 lang_wild_statement_enum, 85 lang_constructors_statement_enum, 86 lang_object_symbols_statement_enum 87 }; 88 89 typedef struct lang_statement_header_struct 90 { 91 /* Next pointer for statement_list statement list. */ 92 union lang_statement_union *next; 93 enum statement_enum type; 94 } lang_statement_header_type; 95 96 typedef struct 97 { 98 lang_statement_header_type header; 99 union etree_union *exp; 100 } lang_assignment_statement_type; 101 102 typedef struct lang_target_statement_struct 103 { 104 lang_statement_header_type header; 105 const char *target; 106 } lang_target_statement_type; 107 108 typedef struct lang_output_statement_struct 109 { 110 lang_statement_header_type header; 111 const char *name; 112 } lang_output_statement_type; 113 114 /* Section types specified in a linker script. */ 115 116 enum section_type 117 { 118 normal_section, 119 first_overlay_section, 120 overlay_section, 121 noload_section, 122 noalloc_section 123 }; 124 125 /* This structure holds a list of program headers describing 126 segments in which this section should be placed. */ 127 128 typedef struct lang_output_section_phdr_list 129 { 130 struct lang_output_section_phdr_list *next; 131 const char *name; 132 bfd_boolean used; 133 } lang_output_section_phdr_list; 134 135 typedef struct lang_output_section_statement_struct 136 { 137 lang_statement_header_type header; 138 lang_statement_list_type children; 139 struct lang_output_section_statement_struct *next; 140 struct lang_output_section_statement_struct *prev; 141 const char *name; 142 asection *bfd_section; 143 lang_memory_region_type *region; 144 lang_memory_region_type *lma_region; 145 fill_type *fill; 146 union etree_union *addr_tree; 147 union etree_union *load_base; 148 union etree_union *section_alignment; 149 union etree_union *subsection_alignment; 150 151 /* If non-null, an expression to evaluate after setting the section's 152 size. The expression is evaluated inside REGION (above) with '.' 153 set to the end of the section. Used in the last overlay section 154 to move '.' past all the overlaid sections. */ 155 union etree_union *update_dot_tree; 156 157 lang_output_section_phdr_list *phdrs; 158 159 unsigned int block_value; 160 int constraint; 161 flagword flags; 162 enum section_type sectype; 163 unsigned int processed_vma : 1; 164 unsigned int processed_lma : 1; 165 unsigned int all_input_readonly : 1; 166 /* If this section should be ignored. */ 167 unsigned int ignored : 1; 168 /* If this section should update "dot". Prevents section being ignored. */ 169 unsigned int update_dot : 1; 170 /* If this section is after assignment to _end. */ 171 unsigned int after_end : 1; 172 /* If this section uses the alignment of its input sections. */ 173 unsigned int align_lma_with_input : 1; 174 } lang_output_section_statement_type; 175 176 typedef struct 177 { 178 lang_statement_header_type header; 179 fill_type *fill; 180 int size; 181 asection *output_section; 182 } lang_fill_statement_type; 183 184 typedef struct 185 { 186 lang_statement_header_type header; 187 unsigned int type; 188 union etree_union *exp; 189 bfd_vma value; 190 asection *output_section; 191 bfd_vma output_offset; 192 } lang_data_statement_type; 193 194 /* Generate a reloc in the output file. */ 195 196 typedef struct 197 { 198 lang_statement_header_type header; 199 200 /* Reloc to generate. */ 201 bfd_reloc_code_real_type reloc; 202 203 /* Reloc howto structure. */ 204 reloc_howto_type *howto; 205 206 /* Section to generate reloc against. 207 Exactly one of section and name must be NULL. */ 208 asection *section; 209 210 /* Name of symbol to generate reloc against. 211 Exactly one of section and name must be NULL. */ 212 const char *name; 213 214 /* Expression for addend. */ 215 union etree_union *addend_exp; 216 217 /* Resolved addend. */ 218 bfd_vma addend_value; 219 220 /* Output section where reloc should be performed. */ 221 asection *output_section; 222 223 /* Offset within output section. */ 224 bfd_vma output_offset; 225 } lang_reloc_statement_type; 226 227 struct lang_input_statement_flags 228 { 229 /* 1 means this file was specified in a -l option. */ 230 unsigned int maybe_archive : 1; 231 232 /* 1 means this file was specified in a -l:namespec option. */ 233 unsigned int full_name_provided : 1; 234 235 /* 1 means search a set of directories for this file. */ 236 unsigned int search_dirs : 1; 237 238 /* 1 means this was found when processing a script in the sysroot. */ 239 unsigned int sysrooted : 1; 240 241 /* 1 means this is base file of incremental load. 242 Do not load this file's text or data. 243 Also default text_start to after this file's bss. */ 244 unsigned int just_syms : 1; 245 246 /* Whether to search for this entry as a dynamic archive. */ 247 unsigned int dynamic : 1; 248 249 /* Set if a DT_NEEDED tag should be added not just for the dynamic library 250 explicitly given by this entry but also for any dynamic libraries in 251 this entry's needed list. */ 252 unsigned int add_DT_NEEDED_for_dynamic : 1; 253 254 /* Set if this entry should cause a DT_NEEDED tag only when some 255 regular file references its symbols (ie. --as-needed is in effect). */ 256 unsigned int add_DT_NEEDED_for_regular : 1; 257 258 /* Whether to include the entire contents of an archive. */ 259 unsigned int whole_archive : 1; 260 261 /* Set when bfd opening is successful. */ 262 unsigned int loaded : 1; 263 264 unsigned int real : 1; 265 266 /* Set if the file does not exist. */ 267 unsigned int missing_file : 1; 268 269 /* Set if reloading an archive or --as-needed lib. */ 270 unsigned int reload : 1; 271 272 #ifdef ENABLE_PLUGINS 273 /* Set if the file was claimed by a plugin. */ 274 unsigned int claimed : 1; 275 276 /* Set if the file was claimed from an archive. */ 277 unsigned int claim_archive : 1; 278 279 /* Set if added by the lto plugin add_input_file callback. */ 280 unsigned int lto_output : 1; 281 #endif /* ENABLE_PLUGINS */ 282 283 /* Head of list of pushed flags. */ 284 struct lang_input_statement_flags *pushed; 285 }; 286 287 typedef struct lang_input_statement_struct 288 { 289 lang_statement_header_type header; 290 /* Name of this file. */ 291 const char *filename; 292 /* Name to use for the symbol giving address of text start. 293 Usually the same as filename, but for a file spec'd with 294 -l this is the -l switch itself rather than the filename. */ 295 const char *local_sym_name; 296 297 bfd *the_bfd; 298 299 ctf_archive_t *the_ctf; 300 301 struct flag_info *section_flag_list; 302 303 /* Next pointer for file_chain statement list. */ 304 struct lang_input_statement_struct *next; 305 306 /* Next pointer for input_file_chain statement list. */ 307 struct lang_input_statement_struct *next_real_file; 308 309 const char *target; 310 311 struct lang_input_statement_flags flags; 312 } lang_input_statement_type; 313 314 typedef struct 315 { 316 lang_statement_header_type header; 317 asection *section; 318 } lang_input_section_type; 319 320 struct map_symbol_def { 321 struct bfd_link_hash_entry *entry; 322 struct map_symbol_def *next; 323 }; 324 325 /* For input sections, when writing a map file: head / tail of a linked 326 list of hash table entries for symbols defined in this section. */ 327 typedef struct input_section_userdata_struct 328 { 329 struct map_symbol_def *map_symbol_def_head; 330 struct map_symbol_def **map_symbol_def_tail; 331 unsigned long map_symbol_def_count; 332 } input_section_userdata_type; 333 334 static inline bfd_boolean 335 bfd_input_just_syms (const bfd *abfd) 336 { 337 lang_input_statement_type *is = bfd_usrdata (abfd); 338 return is != NULL && is->flags.just_syms; 339 } 340 341 typedef struct lang_wild_statement_struct lang_wild_statement_type; 342 343 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *, 344 asection *, struct flag_info *, 345 lang_input_statement_type *, void *); 346 347 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *, 348 lang_input_statement_type *, 349 callback_t callback, 350 void *data); 351 352 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *, 353 bfd *, const asection *); 354 355 /* Binary search tree structure to efficiently sort sections by 356 name. */ 357 typedef struct lang_section_bst 358 { 359 asection *section; 360 struct lang_section_bst *left; 361 struct lang_section_bst *right; 362 } lang_section_bst_type; 363 364 struct lang_wild_statement_struct 365 { 366 lang_statement_header_type header; 367 const char *filename; 368 bfd_boolean filenames_sorted; 369 struct wildcard_list *section_list; 370 bfd_boolean keep_sections; 371 lang_statement_list_type children; 372 struct name_list *exclude_name_list; 373 374 walk_wild_section_handler_t walk_wild_section_handler; 375 struct wildcard_list *handler_data[4]; 376 lang_section_bst_type *tree; 377 struct flag_info *section_flag_list; 378 }; 379 380 typedef struct lang_address_statement_struct 381 { 382 lang_statement_header_type header; 383 const char *section_name; 384 union etree_union *address; 385 const segment_type *segment; 386 } lang_address_statement_type; 387 388 typedef struct 389 { 390 lang_statement_header_type header; 391 bfd_vma output_offset; 392 bfd_size_type size; 393 asection *output_section; 394 fill_type *fill; 395 } lang_padding_statement_type; 396 397 /* A group statement collects a set of libraries together. The 398 libraries are searched multiple times, until no new undefined 399 symbols are found. The effect is to search a group of libraries as 400 though they were a single library. */ 401 402 typedef struct 403 { 404 lang_statement_header_type header; 405 lang_statement_list_type children; 406 } lang_group_statement_type; 407 408 typedef struct 409 { 410 lang_statement_header_type header; 411 const char *where; 412 bfd_boolean is_before; 413 } lang_insert_statement_type; 414 415 typedef union lang_statement_union 416 { 417 lang_statement_header_type header; 418 lang_address_statement_type address_statement; 419 lang_assignment_statement_type assignment_statement; 420 lang_data_statement_type data_statement; 421 lang_fill_statement_type fill_statement; 422 lang_group_statement_type group_statement; 423 lang_input_section_type input_section; 424 lang_input_statement_type input_statement; 425 lang_insert_statement_type insert_statement; 426 lang_output_section_statement_type output_section_statement; 427 lang_output_statement_type output_statement; 428 lang_padding_statement_type padding_statement; 429 lang_reloc_statement_type reloc_statement; 430 lang_target_statement_type target_statement; 431 lang_wild_statement_type wild_statement; 432 } lang_statement_union_type; 433 434 /* This structure holds information about a program header, from the 435 PHDRS command in the linker script. */ 436 437 struct lang_phdr 438 { 439 struct lang_phdr *next; 440 const char *name; 441 unsigned long type; 442 bfd_boolean filehdr; 443 bfd_boolean phdrs; 444 etree_type *at; 445 etree_type *flags; 446 }; 447 448 /* This structure is used to hold a list of sections which may not 449 cross reference each other. */ 450 451 typedef struct lang_nocrossref 452 { 453 struct lang_nocrossref *next; 454 const char *name; 455 } lang_nocrossref_type; 456 457 /* The list of nocrossref lists. */ 458 459 struct lang_nocrossrefs 460 { 461 struct lang_nocrossrefs *next; 462 lang_nocrossref_type *list; 463 bfd_boolean onlyfirst; 464 }; 465 466 /* This structure is used to hold a list of input section names which 467 will not match an output section in the linker script. */ 468 469 struct unique_sections 470 { 471 struct unique_sections *next; 472 const char *name; 473 }; 474 475 /* Used by place_orphan to keep track of orphan sections and statements. */ 476 477 struct orphan_save 478 { 479 const char *name; 480 flagword flags; 481 lang_output_section_statement_type *os; 482 asection **section; 483 lang_statement_union_type **stmt; 484 lang_output_section_statement_type **os_tail; 485 }; 486 487 struct asneeded_minfo 488 { 489 struct asneeded_minfo *next; 490 const char *soname; 491 bfd *ref; 492 const char *name; 493 }; 494 495 extern struct lang_phdr *lang_phdr_list; 496 extern struct lang_nocrossrefs *nocrossref_list; 497 extern const char *output_target; 498 extern lang_output_section_statement_type *abs_output_section; 499 extern lang_statement_list_type lang_os_list; 500 extern struct lang_input_statement_flags input_flags; 501 extern bfd_boolean lang_has_input_file; 502 extern lang_statement_list_type *stat_ptr; 503 extern bfd_boolean delete_output_file_on_failure; 504 505 extern struct bfd_sym_chain entry_symbol; 506 extern const char *entry_section; 507 extern bfd_boolean entry_from_cmdline; 508 extern lang_statement_list_type file_chain; 509 extern lang_statement_list_type input_file_chain; 510 511 extern int lang_statement_iteration; 512 extern struct asneeded_minfo **asneeded_list_tail; 513 514 extern void (*output_bfd_hash_table_free_fn) (struct bfd_link_hash_table *); 515 516 extern void lang_init 517 (void); 518 extern void lang_finish 519 (void); 520 extern lang_memory_region_type * lang_memory_region_lookup 521 (const char * const, bfd_boolean); 522 extern void lang_memory_region_alias 523 (const char *, const char *); 524 extern void lang_map 525 (void); 526 extern void lang_set_flags 527 (lang_memory_region_type *, const char *, int); 528 extern void lang_add_output 529 (const char *, int from_script); 530 extern lang_output_section_statement_type *lang_enter_output_section_statement 531 (const char *, etree_type *, enum section_type, etree_type *, etree_type *, 532 etree_type *, int, int); 533 extern void lang_final 534 (void); 535 extern void lang_relax_sections 536 (bfd_boolean); 537 extern void lang_process 538 (void); 539 extern void lang_section_start 540 (const char *, union etree_union *, const segment_type *); 541 extern void lang_add_entry 542 (const char *, bfd_boolean); 543 extern void lang_default_entry 544 (const char *); 545 extern void lang_add_target 546 (const char *); 547 extern void lang_add_wild 548 (struct wildcard_spec *, struct wildcard_list *, bfd_boolean); 549 extern void lang_add_map 550 (const char *); 551 extern void lang_add_fill 552 (fill_type *); 553 extern lang_assignment_statement_type *lang_add_assignment 554 (union etree_union *); 555 extern void lang_add_attribute 556 (enum statement_enum); 557 extern void lang_startup 558 (const char *); 559 extern void lang_float 560 (bfd_boolean); 561 extern void lang_leave_output_section_statement 562 (fill_type *, const char *, lang_output_section_phdr_list *, 563 const char *); 564 extern void lang_for_each_input_file 565 (void (*dothis) (lang_input_statement_type *)); 566 extern void lang_for_each_file 567 (void (*dothis) (lang_input_statement_type *)); 568 extern void lang_reset_memory_regions 569 (void); 570 extern void lang_do_assignments 571 (lang_phase_type); 572 extern asection *section_for_dot 573 (void); 574 575 #define LANG_FOR_EACH_INPUT_STATEMENT(statement) \ 576 lang_input_statement_type *statement; \ 577 for (statement = (lang_input_statement_type *) file_chain.head; \ 578 statement != NULL; \ 579 statement = statement->next) 580 581 #define lang_output_section_find(NAME) \ 582 lang_output_section_statement_lookup (NAME, 0, FALSE) 583 584 extern void lang_process 585 (void); 586 extern void ldlang_add_file 587 (lang_input_statement_type *); 588 extern lang_output_section_statement_type *lang_output_section_find_by_flags 589 (const asection *, flagword, lang_output_section_statement_type **, 590 lang_match_sec_type_func); 591 extern lang_output_section_statement_type *lang_insert_orphan 592 (asection *, const char *, int, lang_output_section_statement_type *, 593 struct orphan_save *, etree_type *, lang_statement_list_type *); 594 extern lang_input_statement_type *lang_add_input_file 595 (const char *, lang_input_file_enum_type, const char *); 596 extern void lang_add_keepsyms_file 597 (const char *); 598 extern lang_output_section_statement_type *lang_output_section_get 599 (const asection *); 600 extern lang_output_section_statement_type *lang_output_section_statement_lookup 601 (const char *, int, bfd_boolean); 602 extern lang_output_section_statement_type *next_matching_output_section_statement 603 (lang_output_section_statement_type *, int); 604 extern void ldlang_add_undef 605 (const char *const, bfd_boolean); 606 extern void ldlang_add_require_defined 607 (const char *const); 608 extern void lang_add_output_format 609 (const char *, const char *, const char *, int); 610 extern void lang_list_init 611 (lang_statement_list_type *); 612 extern void push_stat_ptr 613 (lang_statement_list_type *); 614 extern void pop_stat_ptr 615 (void); 616 extern void lang_add_data 617 (int type, union etree_union *); 618 extern void lang_add_reloc 619 (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *, 620 union etree_union *); 621 extern void lang_for_each_statement 622 (void (*) (lang_statement_union_type *)); 623 extern void lang_for_each_statement_worker 624 (void (*) (lang_statement_union_type *), lang_statement_union_type *); 625 extern void *stat_alloc 626 (size_t); 627 extern void strip_excluded_output_sections 628 (void); 629 extern void lang_clear_os_map 630 (void); 631 extern void dprint_statement 632 (lang_statement_union_type *, int); 633 extern void lang_size_sections 634 (bfd_boolean *, bfd_boolean); 635 extern void one_lang_size_sections_pass 636 (bfd_boolean *, bfd_boolean); 637 extern void lang_add_insert 638 (const char *, int); 639 extern void lang_enter_group 640 (void); 641 extern void lang_leave_group 642 (void); 643 extern void lang_add_section 644 (lang_statement_list_type *, asection *, 645 struct flag_info *, lang_output_section_statement_type *); 646 extern void lang_new_phdr 647 (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *, 648 etree_type *); 649 extern void lang_add_nocrossref 650 (lang_nocrossref_type *); 651 extern void lang_add_nocrossref_to 652 (lang_nocrossref_type *); 653 extern void lang_enter_overlay 654 (etree_type *, etree_type *); 655 extern void lang_enter_overlay_section 656 (const char *); 657 extern void lang_leave_overlay_section 658 (fill_type *, lang_output_section_phdr_list *); 659 extern void lang_leave_overlay 660 (etree_type *, int, fill_type *, const char *, 661 lang_output_section_phdr_list *, const char *); 662 663 extern struct bfd_elf_version_expr *lang_new_vers_pattern 664 (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean); 665 extern struct bfd_elf_version_tree *lang_new_vers_node 666 (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *); 667 extern struct bfd_elf_version_deps *lang_add_vers_depend 668 (struct bfd_elf_version_deps *, const char *); 669 extern void lang_register_vers_node 670 (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *); 671 extern void lang_append_dynamic_list (struct bfd_elf_version_expr *); 672 extern void lang_append_dynamic_list_cpp_typeinfo (void); 673 extern void lang_append_dynamic_list_cpp_new (void); 674 extern void lang_add_unique 675 (const char *); 676 extern const char *lang_get_output_target 677 (void); 678 extern void add_excluded_libs (const char *); 679 extern bfd_boolean load_symbols 680 (lang_input_statement_type *, lang_statement_list_type *); 681 682 struct elf_sym_strtab; 683 struct elf_strtab_hash; 684 extern void ldlang_ctf_apply_strsym 685 (struct elf_sym_strtab *, bfd_size_type, struct elf_strtab_hash *); 686 extern void ldlang_write_ctf_late 687 (void); 688 extern bfd_boolean 689 ldlang_override_segment_assignment 690 (struct bfd_link_info *, bfd *, asection *, asection *, bfd_boolean); 691 692 extern void 693 lang_ld_feature (char *); 694 695 extern void 696 lang_print_memory_usage (void); 697 698 extern void 699 lang_add_gc_name (const char *); 700 701 #endif 702