1 /* ldlang.h - linker command language support 2 Copyright (C) 1991-2016 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_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 89 typedef struct lang_statement_header_struct 90 { 91 union lang_statement_union *next; 92 enum statement_enum type; 93 } lang_statement_header_type; 94 95 typedef struct 96 { 97 lang_statement_header_type header; 98 union etree_union *exp; 99 } lang_assignment_statement_type; 100 101 typedef struct lang_target_statement_struct 102 { 103 lang_statement_header_type header; 104 const char *target; 105 } lang_target_statement_type; 106 107 typedef 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. */ 114 115 enum 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. */ 125 126 typedef 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; 132 133 typedef 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; 173 174 typedef struct 175 { 176 lang_statement_header_type header; 177 } lang_common_statement_type; 178 179 typedef struct 180 { 181 lang_statement_header_type header; 182 } lang_object_symbols_statement_type; 183 184 typedef struct 185 { 186 lang_statement_header_type header; 187 fill_type *fill; 188 int size; 189 asection *output_section; 190 } lang_fill_statement_type; 191 192 typedef 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. */ 203 204 typedef 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; 234 235 struct 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 }; 294 295 typedef 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; 320 321 typedef struct 322 { 323 lang_statement_header_type header; 324 asection *section; 325 } lang_input_section_type; 326 327 struct 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. */ 334 typedef 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) 342 343 344 typedef struct lang_wild_statement_struct lang_wild_statement_type; 345 346 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *, 347 asection *, struct flag_info *, 348 lang_input_statement_type *, void *); 349 350 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *, 351 lang_input_statement_type *, 352 callback_t callback, 353 void *data); 354 355 typedef 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. */ 360 typedef 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; 366 367 struct 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; 375 376 walk_wild_section_handler_t walk_wild_section_handler; 377 struct wildcard_list *handler_data[4]; 378 lang_section_bst_type *tree; 379 struct flag_info *section_flag_list; 380 }; 381 382 typedef struct lang_address_statement_struct 383 { 384 lang_statement_header_type header; 385 const char *section_name; 386 union etree_union *address; 387 const segment_type *segment; 388 } lang_address_statement_type; 389 390 typedef struct 391 { 392 lang_statement_header_type header; 393 bfd_vma output_offset; 394 bfd_size_type size; 395 asection *output_section; 396 fill_type *fill; 397 } lang_padding_statement_type; 398 399 /* A group statement collects a set of libraries together. The 400 libraries are searched multiple times, until no new undefined 401 symbols are found. The effect is to search a group of libraries as 402 though they were a single library. */ 403 404 typedef struct 405 { 406 lang_statement_header_type header; 407 lang_statement_list_type children; 408 } lang_group_statement_type; 409 410 typedef struct 411 { 412 lang_statement_header_type header; 413 const char *where; 414 bfd_boolean is_before; 415 } lang_insert_statement_type; 416 417 typedef union lang_statement_union 418 { 419 lang_statement_header_type header; 420 lang_wild_statement_type wild_statement; 421 lang_data_statement_type data_statement; 422 lang_reloc_statement_type reloc_statement; 423 lang_address_statement_type address_statement; 424 lang_output_section_statement_type output_section_statement; 425 lang_assignment_statement_type assignment_statement; 426 lang_input_statement_type input_statement; 427 lang_target_statement_type target_statement; 428 lang_output_statement_type output_statement; 429 lang_input_section_type input_section; 430 lang_common_statement_type common_statement; 431 lang_object_symbols_statement_type object_symbols_statement; 432 lang_fill_statement_type fill_statement; 433 lang_padding_statement_type padding_statement; 434 lang_group_statement_type group_statement; 435 lang_insert_statement_type insert_statement; 436 } lang_statement_union_type; 437 438 /* This structure holds information about a program header, from the 439 PHDRS command in the linker script. */ 440 441 struct lang_phdr 442 { 443 struct lang_phdr *next; 444 const char *name; 445 unsigned long type; 446 bfd_boolean filehdr; 447 bfd_boolean phdrs; 448 etree_type *at; 449 etree_type *flags; 450 }; 451 452 /* This structure is used to hold a list of sections which may not 453 cross reference each other. */ 454 455 typedef struct lang_nocrossref 456 { 457 struct lang_nocrossref *next; 458 const char *name; 459 } lang_nocrossref_type; 460 461 /* The list of nocrossref lists. */ 462 463 struct lang_nocrossrefs 464 { 465 struct lang_nocrossrefs *next; 466 lang_nocrossref_type *list; 467 bfd_boolean onlyfirst; 468 }; 469 470 /* This structure is used to hold a list of input section names which 471 will not match an output section in the linker script. */ 472 473 struct unique_sections 474 { 475 struct unique_sections *next; 476 const char *name; 477 }; 478 479 /* Used by place_orphan to keep track of orphan sections and statements. */ 480 481 struct orphan_save 482 { 483 const char *name; 484 flagword flags; 485 lang_output_section_statement_type *os; 486 asection **section; 487 lang_statement_union_type **stmt; 488 lang_output_section_statement_type **os_tail; 489 }; 490 491 struct asneeded_minfo 492 { 493 struct asneeded_minfo *next; 494 const char *soname; 495 bfd *ref; 496 const char *name; 497 }; 498 499 extern struct lang_phdr *lang_phdr_list; 500 extern struct lang_nocrossrefs *nocrossref_list; 501 extern const char *output_target; 502 extern lang_output_section_statement_type *abs_output_section; 503 extern lang_statement_list_type lang_output_section_statement; 504 extern struct lang_input_statement_flags input_flags; 505 extern bfd_boolean lang_has_input_file; 506 extern lang_statement_list_type *stat_ptr; 507 extern bfd_boolean delete_output_file_on_failure; 508 509 extern struct bfd_sym_chain entry_symbol; 510 extern const char *entry_section; 511 extern bfd_boolean entry_from_cmdline; 512 extern lang_statement_list_type file_chain; 513 extern lang_statement_list_type input_file_chain; 514 515 extern int lang_statement_iteration; 516 extern struct asneeded_minfo **asneeded_list_tail; 517 518 extern void (*output_bfd_hash_table_free_fn) (struct bfd_link_hash_table *); 519 520 extern void lang_init 521 (void); 522 extern void lang_finish 523 (void); 524 extern lang_memory_region_type * lang_memory_region_lookup 525 (const char * const, bfd_boolean); 526 extern void lang_memory_region_alias 527 (const char *, const char *); 528 extern void lang_map 529 (void); 530 extern void lang_set_flags 531 (lang_memory_region_type *, const char *, int); 532 extern void lang_add_output 533 (const char *, int from_script); 534 extern lang_output_section_statement_type *lang_enter_output_section_statement 535 (const char *, etree_type *, enum section_type, etree_type *, etree_type *, 536 etree_type *, int, int); 537 extern void lang_final 538 (void); 539 extern void lang_relax_sections 540 (bfd_boolean); 541 extern void lang_process 542 (void); 543 extern void lang_section_start 544 (const char *, union etree_union *, const segment_type *); 545 extern void lang_add_entry 546 (const char *, bfd_boolean); 547 extern void lang_default_entry 548 (const char *); 549 extern void lang_add_target 550 (const char *); 551 extern void lang_add_wild 552 (struct wildcard_spec *, struct wildcard_list *, bfd_boolean); 553 extern void lang_add_map 554 (const char *); 555 extern void lang_add_fill 556 (fill_type *); 557 extern lang_assignment_statement_type *lang_add_assignment 558 (union etree_union *); 559 extern void lang_add_attribute 560 (enum statement_enum); 561 extern void lang_startup 562 (const char *); 563 extern void lang_float 564 (bfd_boolean); 565 extern void lang_leave_output_section_statement 566 (fill_type *, const char *, lang_output_section_phdr_list *, 567 const char *); 568 extern void lang_statement_append 569 (lang_statement_list_type *, lang_statement_union_type *, 570 lang_statement_union_type **); 571 extern void lang_for_each_input_file 572 (void (*dothis) (lang_input_statement_type *)); 573 extern void lang_for_each_file 574 (void (*dothis) (lang_input_statement_type *)); 575 extern void lang_reset_memory_regions 576 (void); 577 extern void lang_do_assignments 578 (lang_phase_type); 579 extern asection *section_for_dot 580 (void); 581 582 #define LANG_FOR_EACH_INPUT_STATEMENT(statement) \ 583 lang_input_statement_type *statement; \ 584 for (statement = (lang_input_statement_type *) file_chain.head; \ 585 statement != (lang_input_statement_type *) NULL; \ 586 statement = (lang_input_statement_type *) statement->next) \ 587 588 #define lang_output_section_find(NAME) \ 589 lang_output_section_statement_lookup (NAME, 0, FALSE) 590 591 extern void lang_process 592 (void); 593 extern void ldlang_add_file 594 (lang_input_statement_type *); 595 extern lang_output_section_statement_type *lang_output_section_find_by_flags 596 (const asection *, flagword, lang_output_section_statement_type **, 597 lang_match_sec_type_func); 598 extern lang_output_section_statement_type *lang_insert_orphan 599 (asection *, const char *, int, lang_output_section_statement_type *, 600 struct orphan_save *, etree_type *, lang_statement_list_type *); 601 extern lang_input_statement_type *lang_add_input_file 602 (const char *, lang_input_file_enum_type, const char *); 603 extern void lang_add_keepsyms_file 604 (const char *); 605 extern lang_output_section_statement_type *lang_output_section_get 606 (const asection *); 607 extern lang_output_section_statement_type *lang_output_section_statement_lookup 608 (const char *, int, bfd_boolean); 609 extern lang_output_section_statement_type *next_matching_output_section_statement 610 (lang_output_section_statement_type *, int); 611 extern void ldlang_add_undef 612 (const char *const, bfd_boolean); 613 extern void ldlang_add_require_defined 614 (const char *const); 615 extern void lang_add_output_format 616 (const char *, const char *, const char *, int); 617 extern void lang_list_init 618 (lang_statement_list_type *); 619 extern void push_stat_ptr 620 (lang_statement_list_type *); 621 extern void pop_stat_ptr 622 (void); 623 extern void lang_add_data 624 (int type, union etree_union *); 625 extern void lang_add_reloc 626 (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *, 627 union etree_union *); 628 extern void lang_for_each_statement 629 (void (*) (lang_statement_union_type *)); 630 extern void lang_for_each_statement_worker 631 (void (*) (lang_statement_union_type *), lang_statement_union_type *); 632 extern void *stat_alloc 633 (size_t); 634 extern void strip_excluded_output_sections 635 (void); 636 extern void lang_clear_os_map 637 (void); 638 extern void dprint_statement 639 (lang_statement_union_type *, int); 640 extern void lang_size_sections 641 (bfd_boolean *, bfd_boolean); 642 extern void one_lang_size_sections_pass 643 (bfd_boolean *, bfd_boolean); 644 extern void lang_add_insert 645 (const char *, int); 646 extern void lang_enter_group 647 (void); 648 extern void lang_leave_group 649 (void); 650 extern void lang_add_section 651 (lang_statement_list_type *, asection *, 652 struct flag_info *, lang_output_section_statement_type *); 653 extern void lang_new_phdr 654 (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *, 655 etree_type *); 656 extern void lang_add_nocrossref 657 (lang_nocrossref_type *); 658 extern void lang_add_nocrossref_to 659 (lang_nocrossref_type *); 660 extern void lang_enter_overlay 661 (etree_type *, etree_type *); 662 extern void lang_enter_overlay_section 663 (const char *); 664 extern void lang_leave_overlay_section 665 (fill_type *, lang_output_section_phdr_list *); 666 extern void lang_leave_overlay 667 (etree_type *, int, fill_type *, const char *, 668 lang_output_section_phdr_list *, const char *); 669 670 extern struct bfd_elf_version_expr *lang_new_vers_pattern 671 (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean); 672 extern struct bfd_elf_version_tree *lang_new_vers_node 673 (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *); 674 extern struct bfd_elf_version_deps *lang_add_vers_depend 675 (struct bfd_elf_version_deps *, const char *); 676 extern void lang_register_vers_node 677 (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *); 678 extern void lang_append_dynamic_list (struct bfd_elf_version_expr *); 679 extern void lang_append_dynamic_list_cpp_typeinfo (void); 680 extern void lang_append_dynamic_list_cpp_new (void); 681 extern void lang_add_unique 682 (const char *); 683 extern const char *lang_get_output_target 684 (void); 685 extern void add_excluded_libs (const char *); 686 extern bfd_boolean load_symbols 687 (lang_input_statement_type *, lang_statement_list_type *); 688 689 extern bfd_boolean 690 ldlang_override_segment_assignment 691 (struct bfd_link_info *, bfd *, asection *, asection *, bfd_boolean); 692 693 extern void 694 lang_ld_feature (char *); 695 696 extern void 697 lang_print_memory_usage (void); 698 699 extern void 700 lang_add_gc_name (const char *); 701 702 #endif 703