ld/ldlang.h

   1 /* ldlang.h - linker command language support
   2    Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   3    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   4    Free Software Foundation, Inc.
   5
   6    This file is part of the GNU Binutils.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21    MA 02110-1301, USA.  */
  22
  23 #ifndef LDLANG_H
  24 #define LDLANG_H
  25
  26 #define DEFAULT_MEMORY_REGION   "*default*"
  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   bfd_vma origin;
  61   bfd_size_type length;
  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 there is a symbol relative to this section.  */
 167   unsigned int section_relative_symbol : 1;
 168 } lang_output_section_statement_type;
 169
 170 typedef struct
 171 {
 172   lang_statement_header_type header;
 173 } lang_common_statement_type;
 174
 175 typedef struct
 176 {
 177   lang_statement_header_type header;
 178 } lang_object_symbols_statement_type;
 179
 180 typedef struct
 181 {
 182   lang_statement_header_type header;
 183   fill_type *fill;
 184   int size;
 185   asection *output_section;
 186 } lang_fill_statement_type;
 187
 188 typedef struct
 189 {
 190   lang_statement_header_type header;
 191   unsigned int type;
 192   union etree_union *exp;
 193   bfd_vma value;
 194   asection *output_section;
 195   bfd_vma output_offset;
 196 } lang_data_statement_type;
 197
 198 /* Generate a reloc in the output file.  */
 199
 200 typedef struct
 201 {
 202   lang_statement_header_type header;
 203
 204   /* Reloc to generate.  */
 205   bfd_reloc_code_real_type reloc;
 206
 207   /* Reloc howto structure.  */
 208   reloc_howto_type *howto;
 209
 210   /* Section to generate reloc against.
 211      Exactly one of section and name must be NULL.  */
 212   asection *section;
 213
 214   /* Name of symbol to generate reloc against.
 215      Exactly one of section and name must be NULL.  */
 216   const char *name;
 217
 218   /* Expression for addend.  */
 219   union etree_union *addend_exp;
 220
 221   /* Resolved addend.  */
 222   bfd_vma addend_value;
 223
 224   /* Output section where reloc should be performed.  */
 225   asection *output_section;
 226
 227   /* Offset within output section.  */
 228   bfd_vma output_offset;
 229 } lang_reloc_statement_type;
 230
 231 typedef struct lang_input_statement_struct
 232 {
 233   lang_statement_header_type header;
 234   /* Name of this file.  */
 235   const char *filename;
 236   /* Name to use for the symbol giving address of text start.
 237      Usually the same as filename, but for a file spec'd with
 238      -l this is the -l switch itself rather than the filename.  */
 239   const char *local_sym_name;
 240
 241   bfd *the_bfd;
 242
 243   /* Point to the next file - whatever it is, wanders up and down
 244      archives */
 245   union lang_statement_union *next;
 246
 247   /* Point to the next file, but skips archive contents.  */
 248   union lang_statement_union *next_real_file;
 249
 250   const char *target;
 251
 252   unsigned int is_archive : 1;
 253
 254   /* 1 means search a set of directories for this file.  */
 255   unsigned int search_dirs_flag : 1;
 256
 257   /* 1 means this was found in a search directory marked as sysrooted,
 258      if search_dirs_flag is false, otherwise, that it should be
 259      searched in ld_sysroot before any other location, as long as it
 260      starts with a slash.  */
 261   unsigned int sysrooted : 1;
 262
 263   /* 1 means this is base file of incremental load.
 264      Do not load this file's text or data.
 265      Also default text_start to after this file's bss.  */
 266   unsigned int just_syms_flag : 1;
 267
 268   /* Whether to search for this entry as a dynamic archive.  */
 269   unsigned int dynamic : 1;
 270
 271   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 272      DT_NEEDED tags from this entry.  */
 273   unsigned int add_needed : 1;
 274
 275   /* Whether this entry should cause a DT_NEEDED tag only when
 276      satisfying references from regular files, or always.  */
 277   unsigned int as_needed : 1;
 278
 279   /* Whether to include the entire contents of an archive.  */
 280   unsigned int whole_archive : 1;
 281
 282   unsigned int loaded : 1;
 283
 284   unsigned int real : 1;
 285 } lang_input_statement_type;
 286
 287 typedef struct
 288 {
 289   lang_statement_header_type header;
 290   asection *section;
 291 } lang_input_section_type;
 292
 293 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 294
 295 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 296                             asection *, lang_input_statement_type *, void *);
 297
 298 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 299                                              lang_input_statement_type *,
 300                                              callback_t callback,
 301                                              void *data);
 302
 303 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 304                                                  bfd *, const asection *);
 305
 306 /* Binary search tree structure to efficiently sort sections by
 307    name.  */
 308 typedef struct lang_section_bst
 309 {
 310   asection *section;
 311   struct lang_section_bst *left;
 312   struct lang_section_bst *right;
 313 } lang_section_bst_type;
 314
 315 struct lang_wild_statement_struct
 316 {
 317   lang_statement_header_type header;
 318   const char *filename;
 319   bfd_boolean filenames_sorted;
 320   struct wildcard_list *section_list;
 321   bfd_boolean keep_sections;
 322   lang_statement_list_type children;
 323
 324   walk_wild_section_handler_t walk_wild_section_handler;
 325   struct wildcard_list *handler_data[4];
 326   lang_section_bst_type *tree;
 327 };
 328
 329 typedef struct lang_address_statement_struct
 330 {
 331   lang_statement_header_type header;
 332   const char *section_name;
 333   union etree_union *address;
 334   const segment_type *segment;
 335 } lang_address_statement_type;
 336
 337 typedef struct
 338 {
 339   lang_statement_header_type header;
 340   bfd_vma output_offset;
 341   size_t size;
 342   asection *output_section;
 343   fill_type *fill;
 344 } lang_padding_statement_type;
 345
 346 /* A group statement collects a set of libraries together.  The
 347    libraries are searched multiple times, until no new undefined
 348    symbols are found.  The effect is to search a group of libraries as
 349    though they were a single library.  */
 350
 351 typedef struct
 352 {
 353   lang_statement_header_type header;
 354   lang_statement_list_type children;
 355 } lang_group_statement_type;
 356
 357 typedef struct
 358 {
 359   lang_statement_header_type header;
 360   const char *where;
 361   bfd_boolean is_before;
 362 } lang_insert_statement_type;
 363
 364 typedef union lang_statement_union
 365 {
 366   lang_statement_header_type header;
 367   lang_wild_statement_type wild_statement;
 368   lang_data_statement_type data_statement;
 369   lang_reloc_statement_type reloc_statement;
 370   lang_address_statement_type address_statement;
 371   lang_output_section_statement_type output_section_statement;
 372   lang_assignment_statement_type assignment_statement;
 373   lang_input_statement_type input_statement;
 374   lang_target_statement_type target_statement;
 375   lang_output_statement_type output_statement;
 376   lang_input_section_type input_section;
 377   lang_common_statement_type common_statement;
 378   lang_object_symbols_statement_type object_symbols_statement;
 379   lang_fill_statement_type fill_statement;
 380   lang_padding_statement_type padding_statement;
 381   lang_group_statement_type group_statement;
 382   lang_insert_statement_type insert_statement;
 383 } lang_statement_union_type;
 384
 385 /* This structure holds information about a program header, from the
 386    PHDRS command in the linker script.  */
 387
 388 struct lang_phdr
 389 {
 390   struct lang_phdr *next;
 391   const char *name;
 392   unsigned long type;
 393   bfd_boolean filehdr;
 394   bfd_boolean phdrs;
 395   etree_type *at;
 396   etree_type *flags;
 397 };
 398
 399 extern struct lang_phdr *lang_phdr_list;
 400
 401 /* This structure is used to hold a list of sections which may not
 402    cross reference each other.  */
 403
 404 typedef struct lang_nocrossref
 405 {
 406   struct lang_nocrossref *next;
 407   const char *name;
 408 } lang_nocrossref_type;
 409
 410 /* The list of nocrossref lists.  */
 411
 412 struct lang_nocrossrefs
 413 {
 414   struct lang_nocrossrefs *next;
 415   lang_nocrossref_type *list;
 416 };
 417
 418 extern struct lang_nocrossrefs *nocrossref_list;
 419
 420 /* This structure is used to hold a list of input section names which
 421    will not match an output section in the linker script.  */
 422
 423 struct unique_sections
 424 {
 425   struct unique_sections *next;
 426   const char *name;
 427 };
 428
 429 /* This structure records symbols for which we need to keep track of
 430    definedness for use in the DEFINED () test.  */
 431
 432 struct lang_definedness_hash_entry
 433 {
 434   struct bfd_hash_entry root;
 435   int iteration;
 436 };
 437
 438 /* Used by place_orphan to keep track of orphan sections and statements.  */
 439
 440 struct orphan_save
 441 {
 442   const char *name;
 443   flagword flags;
 444   lang_output_section_statement_type *os;
 445   asection **section;
 446   lang_statement_union_type **stmt;
 447   lang_output_section_statement_type **os_tail;
 448 };
 449
 450 extern const char *output_target;
 451 extern lang_output_section_statement_type *abs_output_section;
 452 extern lang_statement_list_type lang_output_section_statement;
 453 extern bfd_boolean lang_has_input_file;
 454 extern etree_type *base;
 455 extern lang_statement_list_type *stat_ptr;
 456 extern bfd_boolean delete_output_file_on_failure;
 457
 458 extern struct bfd_sym_chain entry_symbol;
 459 extern const char *entry_section;
 460 extern bfd_boolean entry_from_cmdline;
 461 extern lang_statement_list_type file_chain;
 462 extern lang_statement_list_type input_file_chain;
 463
 464 extern int lang_statement_iteration;
 465
 466 extern void lang_init
 467   (void);
 468 extern void lang_finish
 469   (void);
 470 extern lang_memory_region_type * lang_memory_region_lookup
 471   (const char * const, bfd_boolean);
 472 extern void lang_memory_region_alias
 473   (const char *, const char *);
 474 extern void lang_map
 475   (void);
 476 extern void lang_set_flags
 477   (lang_memory_region_type *, const char *, int);
 478 extern void lang_add_output
 479   (const char *, int from_script);
 480 extern lang_output_section_statement_type *lang_enter_output_section_statement
 481   (const char *output_section_statement_name,
 482    etree_type *address_exp,
 483    enum section_type sectype,
 484    etree_type *align,
 485    etree_type *subalign,
 486    etree_type *, int);
 487 extern void lang_final
 488   (void);
 489 extern void lang_relax_sections
 490   (bfd_boolean);
 491 extern void lang_process
 492   (void);
 493 extern void lang_section_start
 494   (const char *, union etree_union *, const segment_type *);
 495 extern void lang_add_entry
 496   (const char *, bfd_boolean);
 497 extern void lang_default_entry
 498   (const char *);
 499 extern void lang_add_target
 500   (const char *);
 501 extern void lang_add_wild
 502   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 503 extern void lang_add_map
 504   (const char *);
 505 extern void lang_add_fill
 506   (fill_type *);
 507 extern lang_assignment_statement_type *lang_add_assignment
 508   (union etree_union *);
 509 extern void lang_add_attribute
 510   (enum statement_enum);
 511 extern void lang_startup
 512   (const char *);
 513 extern void lang_float
 514   (bfd_boolean);
 515 extern void lang_leave_output_section_statement
 516   (fill_type *, const char *, lang_output_section_phdr_list *,
 517    const char *);
 518 extern void lang_abs_symbol_at_end_of
 519   (const char *, const char *);
 520 extern void lang_abs_symbol_at_beginning_of
 521   (const char *, const char *);
 522 extern void lang_statement_append
 523   (lang_statement_list_type *, lang_statement_union_type *,
 524    lang_statement_union_type **);
 525 extern void lang_for_each_input_file
 526   (void (*dothis) (lang_input_statement_type *));
 527 extern void lang_for_each_file
 528   (void (*dothis) (lang_input_statement_type *));
 529 extern void lang_reset_memory_regions
 530   (void);
 531 extern void lang_do_assignments
 532   (void);
 533
 534 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 535   lang_input_statement_type *statement;                                 \
 536   for (statement = (lang_input_statement_type *) file_chain.head;       \
 537        statement != (lang_input_statement_type *) NULL;                 \
 538        statement = (lang_input_statement_type *) statement->next)       \
 539
 540 #define lang_output_section_find(NAME) \
 541   lang_output_section_statement_lookup (NAME, 0, FALSE)
 542
 543 extern void lang_process
 544   (void);
 545 extern void ldlang_add_file
 546   (lang_input_statement_type *);
 547 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 548   (const asection *, lang_output_section_statement_type **,
 549    lang_match_sec_type_func);
 550 extern lang_output_section_statement_type *lang_insert_orphan
 551   (asection *, const char *, int, lang_output_section_statement_type *,
 552    struct orphan_save *, etree_type *, lang_statement_list_type *);
 553 extern lang_input_statement_type *lang_add_input_file
 554   (const char *, lang_input_file_enum_type, const char *);
 555 extern void lang_add_keepsyms_file
 556   (const char *);
 557 extern lang_output_section_statement_type *lang_output_section_statement_lookup
 558   (const char *, int, bfd_boolean);
 559 extern lang_output_section_statement_type *next_matching_output_section_statement
 560   (lang_output_section_statement_type *, int);
 561 extern void ldlang_add_undef
 562   (const char *const);
 563 extern void lang_add_output_format
 564   (const char *, const char *, const char *, int);
 565 extern void lang_list_init
 566   (lang_statement_list_type *);
 567 extern void push_stat_ptr
 568   (lang_statement_list_type *);
 569 extern void pop_stat_ptr
 570   (void);
 571 extern void lang_add_data
 572   (int type, union etree_union *);
 573 extern void lang_add_reloc
 574   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 575    union etree_union *);
 576 extern void lang_for_each_statement
 577   (void (*) (lang_statement_union_type *));
 578 extern void *stat_alloc
 579   (size_t);
 580 extern void strip_excluded_output_sections
 581   (void);
 582 extern void dprint_statement
 583   (lang_statement_union_type *, int);
 584 extern void lang_size_sections
 585   (bfd_boolean *, bfd_boolean);
 586 extern void one_lang_size_sections_pass
 587   (bfd_boolean *, bfd_boolean);
 588 extern void lang_add_insert
 589   (const char *, int);
 590 extern void lang_enter_group
 591   (void);
 592 extern void lang_leave_group
 593   (void);
 594 extern void lang_add_section
 595   (lang_statement_list_type *, asection *,
 596    lang_output_section_statement_type *);
 597 extern void lang_new_phdr
 598   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 599    etree_type *);
 600 extern void lang_add_nocrossref
 601   (lang_nocrossref_type *);
 602 extern void lang_enter_overlay
 603   (etree_type *, etree_type *);
 604 extern void lang_enter_overlay_section
 605   (const char *);
 606 extern void lang_leave_overlay_section
 607   (fill_type *, lang_output_section_phdr_list *);
 608 extern void lang_leave_overlay
 609   (etree_type *, int, fill_type *, const char *,
 610    lang_output_section_phdr_list *, const char *);
 611
 612 extern struct bfd_elf_version_tree *lang_elf_version_info;
 613
 614 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 615   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 616 extern struct bfd_elf_version_tree *lang_new_vers_node
 617   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 618 extern struct bfd_elf_version_deps *lang_add_vers_depend
 619   (struct bfd_elf_version_deps *, const char *);
 620 extern void lang_register_vers_node
 621   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 622 extern void lang_append_dynamic_list (struct bfd_elf_version_expr *);
 623 extern void lang_append_dynamic_list_cpp_typeinfo (void);
 624 extern void lang_append_dynamic_list_cpp_new (void);
 625 extern void lang_add_unique
 626   (const char *);
 627 extern const char *lang_get_output_target
 628   (void);
 629 extern void lang_track_definedness (const char *);
 630 extern int lang_symbol_definition_iteration (const char *);
 631 extern void lang_update_definedness
 632   (const char *, struct bfd_link_hash_entry *);
 633
 634 extern void add_excluded_libs (const char *);
 635 extern bfd_boolean load_symbols
 636   (lang_input_statement_type *, lang_statement_list_type *);
 637
 638 extern bfd_boolean
 639 ldlang_override_segment_assignment
 640   (struct bfd_link_info *, bfd *, asection *, asection *, bfd_boolean);
 641
 642 #endif