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 typedef struct lang_statement_header_struct
  70 {
  71   union lang_statement_union *next;
  72   enum statement_enum
  73   {
  74     lang_output_section_statement_enum,
  75     lang_assignment_statement_enum,
  76     lang_input_statement_enum,
  77     lang_address_statement_enum,
  78     lang_wild_statement_enum,
  79     lang_input_section_enum,
  80     lang_object_symbols_statement_enum,
  81     lang_fill_statement_enum,
  82     lang_data_statement_enum,
  83     lang_reloc_statement_enum,
  84     lang_target_statement_enum,
  85     lang_output_statement_enum,
  86     lang_padding_statement_enum,
  87     lang_group_statement_enum,
  88     lang_insert_statement_enum,
  89     lang_constructors_statement_enum
  90   } type;
  91 } lang_statement_header_type;
  92
  93 typedef struct
  94 {
  95   lang_statement_header_type header;
  96   union etree_union *exp;
  97 } lang_assignment_statement_type;
  98
  99 typedef struct lang_target_statement_struct
 100 {
 101   lang_statement_header_type header;
 102   const char *target;
 103 } lang_target_statement_type;
 104
 105 typedef struct lang_output_statement_struct
 106 {
 107   lang_statement_header_type header;
 108   const char *name;
 109 } lang_output_statement_type;
 110
 111 /* Section types specified in a linker script.  */
 112
 113 enum section_type
 114 {
 115   normal_section,
 116   overlay_section,
 117   noload_section,
 118   noalloc_section
 119 };
 120
 121 /* This structure holds a list of program headers describing
 122    segments in which this section should be placed.  */
 123
 124 typedef struct lang_output_section_phdr_list
 125 {
 126   struct lang_output_section_phdr_list *next;
 127   const char *name;
 128   bfd_boolean used;
 129 } lang_output_section_phdr_list;
 130
 131 typedef struct lang_output_section_statement_struct
 132 {
 133   lang_statement_header_type header;
 134   lang_statement_list_type children;
 135   struct lang_output_section_statement_struct *next;
 136   struct lang_output_section_statement_struct *prev;
 137   const char *name;
 138   asection *bfd_section;
 139   lang_memory_region_type *region;
 140   lang_memory_region_type *lma_region;
 141   fill_type *fill;
 142   union etree_union *addr_tree;
 143   union etree_union *load_base;
 144
 145   /* If non-null, an expression to evaluate after setting the section's
 146      size.  The expression is evaluated inside REGION (above) with '.'
 147      set to the end of the section.  Used in the last overlay section
 148      to move '.' past all the overlaid sections.  */
 149   union etree_union *update_dot_tree;
 150
 151   lang_output_section_phdr_list *phdrs;
 152
 153   unsigned int block_value;
 154   int subsection_alignment;     /* Alignment of components.  */
 155   int section_alignment;        /* Alignment of start of section.  */
 156   int constraint;
 157   flagword flags;
 158   enum section_type sectype;
 159   unsigned int processed_vma : 1;
 160   unsigned int processed_lma : 1;
 161   unsigned int all_input_readonly : 1;
 162   /* If this section should be ignored.  */
 163   unsigned int ignored : 1;
 164   /* If there is a symbol relative to this section.  */
 165   unsigned int section_relative_symbol : 1;
 166 } lang_output_section_statement_type;
 167
 168 typedef struct
 169 {
 170   lang_statement_header_type header;
 171 } lang_common_statement_type;
 172
 173 typedef struct
 174 {
 175   lang_statement_header_type header;
 176 } lang_object_symbols_statement_type;
 177
 178 typedef struct
 179 {
 180   lang_statement_header_type header;
 181   fill_type *fill;
 182   int size;
 183   asection *output_section;
 184 } lang_fill_statement_type;
 185
 186 typedef struct
 187 {
 188   lang_statement_header_type header;
 189   unsigned int type;
 190   union etree_union *exp;
 191   bfd_vma value;
 192   asection *output_section;
 193   bfd_vma output_offset;
 194 } lang_data_statement_type;
 195
 196 /* Generate a reloc in the output file.  */
 197
 198 typedef struct
 199 {
 200   lang_statement_header_type header;
 201
 202   /* Reloc to generate.  */
 203   bfd_reloc_code_real_type reloc;
 204
 205   /* Reloc howto structure.  */
 206   reloc_howto_type *howto;
 207
 208   /* Section to generate reloc against.
 209      Exactly one of section and name must be NULL.  */
 210   asection *section;
 211
 212   /* Name of symbol to generate reloc against.
 213      Exactly one of section and name must be NULL.  */
 214   const char *name;
 215
 216   /* Expression for addend.  */
 217   union etree_union *addend_exp;
 218
 219   /* Resolved addend.  */
 220   bfd_vma addend_value;
 221
 222   /* Output section where reloc should be performed.  */
 223   asection *output_section;
 224
 225   /* Offset within output section.  */
 226   bfd_vma output_offset;
 227 } lang_reloc_statement_type;
 228
 229 typedef struct lang_input_statement_struct
 230 {
 231   lang_statement_header_type header;
 232   /* Name of this file.  */
 233   const char *filename;
 234   /* Name to use for the symbol giving address of text start.
 235      Usually the same as filename, but for a file spec'd with
 236      -l this is the -l switch itself rather than the filename.  */
 237   const char *local_sym_name;
 238
 239   bfd *the_bfd;
 240
 241   /* Point to the next file - whatever it is, wanders up and down
 242      archives */
 243   union lang_statement_union *next;
 244
 245   /* Point to the next file, but skips archive contents.  */
 246   union lang_statement_union *next_real_file;
 247
 248   const char *target;
 249
 250   unsigned int is_archive : 1;
 251
 252   /* 1 means search a set of directories for this file.  */
 253   unsigned int search_dirs_flag : 1;
 254
 255   /* 1 means this was found in a search directory marked as sysrooted,
 256      if search_dirs_flag is false, otherwise, that it should be
 257      searched in ld_sysroot before any other location, as long as it
 258      starts with a slash.  */
 259   unsigned int sysrooted : 1;
 260
 261   /* 1 means this is base file of incremental load.
 262      Do not load this file's text or data.
 263      Also default text_start to after this file's bss.  */
 264   unsigned int just_syms_flag : 1;
 265
 266   /* Whether to search for this entry as a dynamic archive.  */
 267   unsigned int dynamic : 1;
 268
 269   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 270      DT_NEEDED tags from this entry.  */
 271   unsigned int add_needed : 1;
 272
 273   /* Whether this entry should cause a DT_NEEDED tag only when
 274      satisfying references from regular files, or always.  */
 275   unsigned int as_needed : 1;
 276
 277   /* Whether to include the entire contents of an archive.  */
 278   unsigned int whole_archive : 1;
 279
 280   unsigned int loaded : 1;
 281
 282   unsigned int real : 1;
 283 } lang_input_statement_type;
 284
 285 typedef struct
 286 {
 287   lang_statement_header_type header;
 288   asection *section;
 289 } lang_input_section_type;
 290
 291 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 292
 293 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 294                             asection *, lang_input_statement_type *, void *);
 295
 296 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 297                                              lang_input_statement_type *,
 298                                              callback_t callback,
 299                                              void *data);
 300
 301 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 302                                                  bfd *, const asection *);
 303
 304 /* Binary search tree structure to efficiently sort sections by
 305    name.  */
 306 typedef struct lang_section_bst
 307 {
 308   asection *section;
 309   struct lang_section_bst *left;
 310   struct lang_section_bst *right;
 311 } lang_section_bst_type;
 312
 313 struct lang_wild_statement_struct
 314 {
 315   lang_statement_header_type header;
 316   const char *filename;
 317   bfd_boolean filenames_sorted;
 318   struct wildcard_list *section_list;
 319   bfd_boolean keep_sections;
 320   lang_statement_list_type children;
 321
 322   walk_wild_section_handler_t walk_wild_section_handler;
 323   struct wildcard_list *handler_data[4];
 324   lang_section_bst_type *tree;
 325 };
 326
 327 typedef struct lang_address_statement_struct
 328 {
 329   lang_statement_header_type header;
 330   const char *section_name;
 331   union etree_union *address;
 332   const segment_type *segment;
 333 } lang_address_statement_type;
 334
 335 typedef struct
 336 {
 337   lang_statement_header_type header;
 338   bfd_vma output_offset;
 339   size_t size;
 340   asection *output_section;
 341   fill_type *fill;
 342 } lang_padding_statement_type;
 343
 344 /* A group statement collects a set of libraries together.  The
 345    libraries are searched multiple times, until no new undefined
 346    symbols are found.  The effect is to search a group of libraries as
 347    though they were a single library.  */
 348
 349 typedef struct
 350 {
 351   lang_statement_header_type header;
 352   lang_statement_list_type children;
 353 } lang_group_statement_type;
 354
 355 typedef struct
 356 {
 357   lang_statement_header_type header;
 358   const char *where;
 359   bfd_boolean is_before;
 360 } lang_insert_statement_type;
 361
 362 typedef union lang_statement_union
 363 {
 364   lang_statement_header_type header;
 365   lang_wild_statement_type wild_statement;
 366   lang_data_statement_type data_statement;
 367   lang_reloc_statement_type reloc_statement;
 368   lang_address_statement_type address_statement;
 369   lang_output_section_statement_type output_section_statement;
 370   lang_assignment_statement_type assignment_statement;
 371   lang_input_statement_type input_statement;
 372   lang_target_statement_type target_statement;
 373   lang_output_statement_type output_statement;
 374   lang_input_section_type input_section;
 375   lang_common_statement_type common_statement;
 376   lang_object_symbols_statement_type object_symbols_statement;
 377   lang_fill_statement_type fill_statement;
 378   lang_padding_statement_type padding_statement;
 379   lang_group_statement_type group_statement;
 380   lang_insert_statement_type insert_statement;
 381 } lang_statement_union_type;
 382
 383 /* This structure holds information about a program header, from the
 384    PHDRS command in the linker script.  */
 385
 386 struct lang_phdr
 387 {
 388   struct lang_phdr *next;
 389   const char *name;
 390   unsigned long type;
 391   bfd_boolean filehdr;
 392   bfd_boolean phdrs;
 393   etree_type *at;
 394   etree_type *flags;
 395 };
 396
 397 extern struct lang_phdr *lang_phdr_list;
 398
 399 /* This structure is used to hold a list of sections which may not
 400    cross reference each other.  */
 401
 402 typedef struct lang_nocrossref
 403 {
 404   struct lang_nocrossref *next;
 405   const char *name;
 406 } lang_nocrossref_type;
 407
 408 /* The list of nocrossref lists.  */
 409
 410 struct lang_nocrossrefs
 411 {
 412   struct lang_nocrossrefs *next;
 413   lang_nocrossref_type *list;
 414 };
 415
 416 extern struct lang_nocrossrefs *nocrossref_list;
 417
 418 /* This structure is used to hold a list of input section names which
 419    will not match an output section in the linker script.  */
 420
 421 struct unique_sections
 422 {
 423   struct unique_sections *next;
 424   const char *name;
 425 };
 426
 427 /* This structure records symbols for which we need to keep track of
 428    definedness for use in the DEFINED () test.  */
 429
 430 struct lang_definedness_hash_entry
 431 {
 432   struct bfd_hash_entry root;
 433   int iteration;
 434 };
 435
 436 /* Used by place_orphan to keep track of orphan sections and statements.  */
 437
 438 struct orphan_save
 439 {
 440   const char *name;
 441   flagword flags;
 442   lang_output_section_statement_type *os;
 443   asection **section;
 444   lang_statement_union_type **stmt;
 445   lang_output_section_statement_type **os_tail;
 446 };
 447
 448 extern lang_output_section_statement_type *abs_output_section;
 449 extern lang_statement_list_type lang_output_section_statement;
 450 extern bfd_boolean lang_has_input_file;
 451 extern etree_type *base;
 452 extern lang_statement_list_type *stat_ptr;
 453 extern bfd_boolean delete_output_file_on_failure;
 454
 455 extern struct bfd_sym_chain entry_symbol;
 456 extern const char *entry_section;
 457 extern bfd_boolean entry_from_cmdline;
 458 extern lang_statement_list_type file_chain;
 459 extern lang_statement_list_type input_file_chain;
 460
 461 extern int lang_statement_iteration;
 462
 463 extern void lang_init
 464   (void);
 465 extern void lang_finish
 466   (void);
 467 extern lang_memory_region_type * lang_memory_region_lookup
 468   (const char * const, bfd_boolean);
 469 extern void lang_memory_region_alias
 470   (const char *, const char *);
 471 extern void lang_map
 472   (void);
 473 extern void lang_set_flags
 474   (lang_memory_region_type *, const char *, int);
 475 extern void lang_add_output
 476   (const char *, int from_script);
 477 extern lang_output_section_statement_type *lang_enter_output_section_statement
 478   (const char *output_section_statement_name,
 479    etree_type *address_exp,
 480    enum section_type sectype,
 481    etree_type *align,
 482    etree_type *subalign,
 483    etree_type *, int);
 484 extern void lang_final
 485   (void);
 486 extern void lang_process
 487   (void);
 488 extern void lang_section_start
 489   (const char *, union etree_union *, const segment_type *);
 490 extern void lang_add_entry
 491   (const char *, bfd_boolean);
 492 extern void lang_default_entry
 493   (const char *);
 494 extern void lang_add_target
 495   (const char *);
 496 extern void lang_add_wild
 497   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 498 extern void lang_add_map
 499   (const char *);
 500 extern void lang_add_fill
 501   (fill_type *);
 502 extern lang_assignment_statement_type *lang_add_assignment
 503   (union etree_union *);
 504 extern void lang_add_attribute
 505   (enum statement_enum);
 506 extern void lang_startup
 507   (const char *);
 508 extern void lang_float
 509   (bfd_boolean);
 510 extern void lang_leave_output_section_statement
 511   (fill_type *, const char *, lang_output_section_phdr_list *,
 512    const char *);
 513 extern void lang_abs_symbol_at_end_of
 514   (const char *, const char *);
 515 extern void lang_abs_symbol_at_beginning_of
 516   (const char *, const char *);
 517 extern void lang_statement_append
 518   (lang_statement_list_type *, lang_statement_union_type *,
 519    lang_statement_union_type **);
 520 extern void lang_for_each_input_file
 521   (void (*dothis) (lang_input_statement_type *));
 522 extern void lang_for_each_file
 523   (void (*dothis) (lang_input_statement_type *));
 524 extern void lang_reset_memory_regions
 525   (void);
 526 extern void lang_do_assignments
 527   (void);
 528
 529 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 530   lang_input_statement_type *statement;                                 \
 531   for (statement = (lang_input_statement_type *) file_chain.head;       \
 532        statement != (lang_input_statement_type *) NULL;                 \
 533        statement = (lang_input_statement_type *) statement->next)       \
 534
 535 #define lang_output_section_find(NAME) \
 536   lang_output_section_statement_lookup (NAME, 0, FALSE)
 537
 538 extern void lang_process
 539   (void);
 540 extern void ldlang_add_file
 541   (lang_input_statement_type *);
 542 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 543   (const asection *, lang_output_section_statement_type **,
 544    lang_match_sec_type_func);
 545 extern lang_output_section_statement_type *lang_insert_orphan
 546   (asection *, const char *, int, lang_output_section_statement_type *,
 547    struct orphan_save *, etree_type *, lang_statement_list_type *);
 548 extern lang_input_statement_type *lang_add_input_file
 549   (const char *, lang_input_file_enum_type, const char *);
 550 extern void lang_add_keepsyms_file
 551   (const char *);
 552 extern lang_output_section_statement_type *lang_output_section_statement_lookup
 553   (const char *, int, bfd_boolean);
 554 extern lang_output_section_statement_type *next_matching_output_section_statement
 555   (lang_output_section_statement_type *, int);
 556 extern void ldlang_add_undef
 557   (const char *const);
 558 extern void lang_add_output_format
 559   (const char *, const char *, const char *, int);
 560 extern void lang_list_init
 561   (lang_statement_list_type *);
 562 extern void push_stat_ptr
 563   (lang_statement_list_type *);
 564 extern void pop_stat_ptr
 565   (void);
 566 extern void lang_add_data
 567   (int type, union etree_union *);
 568 extern void lang_add_reloc
 569   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 570    union etree_union *);
 571 extern void lang_for_each_statement
 572   (void (*) (lang_statement_union_type *));
 573 extern void *stat_alloc
 574   (size_t);
 575 extern void strip_excluded_output_sections
 576   (void);
 577 extern void dprint_statement
 578   (lang_statement_union_type *, int);
 579 extern void lang_size_sections
 580   (bfd_boolean *, bfd_boolean);
 581 extern void one_lang_size_sections_pass
 582   (bfd_boolean *, bfd_boolean);
 583 extern void lang_add_insert
 584   (const char *, int);
 585 extern void lang_enter_group
 586   (void);
 587 extern void lang_leave_group
 588   (void);
 589 extern void lang_add_section
 590   (lang_statement_list_type *, asection *,
 591    lang_output_section_statement_type *);
 592 extern void lang_new_phdr
 593   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 594    etree_type *);
 595 extern void lang_add_nocrossref
 596   (lang_nocrossref_type *);
 597 extern void lang_enter_overlay
 598   (etree_type *, etree_type *);
 599 extern void lang_enter_overlay_section
 600   (const char *);
 601 extern void lang_leave_overlay_section
 602   (fill_type *, lang_output_section_phdr_list *);
 603 extern void lang_leave_overlay
 604   (etree_type *, int, fill_type *, const char *,
 605    lang_output_section_phdr_list *, const char *);
 606
 607 extern struct bfd_elf_version_tree *lang_elf_version_info;
 608
 609 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 610   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 611 extern struct bfd_elf_version_tree *lang_new_vers_node
 612   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 613 extern struct bfd_elf_version_deps *lang_add_vers_depend
 614   (struct bfd_elf_version_deps *, const char *);
 615 extern void lang_register_vers_node
 616   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 617 extern void lang_append_dynamic_list (struct bfd_elf_version_expr *);
 618 extern void lang_append_dynamic_list_cpp_typeinfo (void);
 619 extern void lang_append_dynamic_list_cpp_new (void);
 620 extern void lang_add_unique
 621   (const char *);
 622 extern const char *lang_get_output_target
 623   (void);
 624 extern void lang_track_definedness (const char *);
 625 extern int lang_symbol_definition_iteration (const char *);
 626 extern void lang_update_definedness
 627   (const char *, struct bfd_link_hash_entry *);
 628
 629 extern void add_excluded_libs (const char *);
 630 extern bfd_boolean load_symbols
 631   (lang_input_statement_type *, lang_statement_list_type *);
 632
 633 extern bfd_boolean
 634 ldlang_override_segment_assignment
 635   (struct bfd_link_info *, bfd *, asection *, asection *, bfd_boolean);
 636
 637 #endif