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
   4    Free Software Foundation, Inc.
   5
   6    This file is part of GLD, the Gnu Linker.
   7
   8    GLD 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 2, or (at your option)
  11    any later version.
  12
  13    GLD 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 GLD; see the file COPYING.  If not, write to the Free
  20    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
  21    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_struct
  51 {
  52   char *name;
  53   struct memory_region_struct *next;
  54   bfd_vma origin;
  55   bfd_size_type length;
  56   bfd_vma current;
  57   bfd_size_type old_length;
  58   flagword flags;
  59   flagword not_flags;
  60   bfd_boolean had_full_message;
  61 } lang_memory_region_type;
  62
  63 typedef struct lang_statement_header_struct
  64 {
  65   union lang_statement_union *next;
  66   enum statement_enum
  67   {
  68     lang_output_section_statement_enum,
  69     lang_assignment_statement_enum,
  70     lang_input_statement_enum,
  71     lang_address_statement_enum,
  72     lang_wild_statement_enum,
  73     lang_input_section_enum,
  74     lang_object_symbols_statement_enum,
  75     lang_fill_statement_enum,
  76     lang_data_statement_enum,
  77     lang_reloc_statement_enum,
  78     lang_target_statement_enum,
  79     lang_output_statement_enum,
  80     lang_padding_statement_enum,
  81     lang_group_statement_enum,
  82
  83     lang_afile_asection_pair_statement_enum,
  84     lang_constructors_statement_enum
  85   } type;
  86 } lang_statement_header_type;
  87
  88 typedef struct
  89 {
  90   lang_statement_header_type header;
  91   union etree_union *exp;
  92 } lang_assignment_statement_type;
  93
  94 typedef struct lang_target_statement_struct
  95 {
  96   lang_statement_header_type header;
  97   const char *target;
  98 } lang_target_statement_type;
  99
 100 typedef struct lang_output_statement_struct
 101 {
 102   lang_statement_header_type header;
 103   const char *name;
 104 } lang_output_statement_type;
 105
 106 /* Section types specified in a linker script.  */
 107
 108 enum section_type
 109 {
 110   normal_section,
 111   noload_section,
 112   noalloc_section
 113 };
 114
 115 /* This structure holds a list of program headers describing
 116    segments in which this section should be placed.  */
 117
 118 typedef struct lang_output_section_phdr_list
 119 {
 120   struct lang_output_section_phdr_list *next;
 121   const char *name;
 122   bfd_boolean used;
 123 } lang_output_section_phdr_list;
 124
 125 typedef struct lang_output_section_statement_struct
 126 {
 127   lang_statement_header_type header;
 128   lang_statement_list_type children;
 129   struct lang_output_section_statement_struct *next;
 130   struct lang_output_section_statement_struct *prev;
 131   const char *name;
 132   asection *bfd_section;
 133   lang_memory_region_type *region;
 134   lang_memory_region_type *lma_region;
 135   fill_type *fill;
 136   union etree_union *addr_tree;
 137   union etree_union *load_base;
 138
 139   /* If non-null, an expression to evaluate after setting the section's
 140      size.  The expression is evaluated inside REGION (above) with '.'
 141      set to the end of the section.  Used in the last overlay section
 142      to move '.' past all the overlaid sections.  */
 143   union etree_union *update_dot_tree;
 144
 145   lang_output_section_phdr_list *phdrs;
 146
 147   unsigned int block_value;
 148   int subsection_alignment;     /* Alignment of components.  */
 149   int section_alignment;        /* Alignment of start of section.  */
 150   int constraint;
 151   flagword flags;
 152   enum section_type sectype;
 153   unsigned int processed : 1;
 154   unsigned int all_input_readonly : 1;
 155   unsigned int ignored : 1;
 156 } lang_output_section_statement_type;
 157
 158 typedef struct
 159 {
 160   lang_statement_header_type header;
 161 } lang_common_statement_type;
 162
 163 typedef struct
 164 {
 165   lang_statement_header_type header;
 166 } lang_object_symbols_statement_type;
 167
 168 typedef struct
 169 {
 170   lang_statement_header_type header;
 171   fill_type *fill;
 172   int size;
 173   asection *output_section;
 174 } lang_fill_statement_type;
 175
 176 typedef struct
 177 {
 178   lang_statement_header_type header;
 179   unsigned int type;
 180   union etree_union *exp;
 181   bfd_vma value;
 182   asection *output_section;
 183   bfd_vma output_offset;
 184 } lang_data_statement_type;
 185
 186 /* Generate a reloc in the output file.  */
 187
 188 typedef struct
 189 {
 190   lang_statement_header_type header;
 191
 192   /* Reloc to generate.  */
 193   bfd_reloc_code_real_type reloc;
 194
 195   /* Reloc howto structure.  */
 196   reloc_howto_type *howto;
 197
 198   /* Section to generate reloc against.
 199      Exactly one of section and name must be NULL.  */
 200   asection *section;
 201
 202   /* Name of symbol to generate reloc against.
 203      Exactly one of section and name must be NULL.  */
 204   const char *name;
 205
 206   /* Expression for addend.  */
 207   union etree_union *addend_exp;
 208
 209   /* Resolved addend.  */
 210   bfd_vma addend_value;
 211
 212   /* Output section where reloc should be performed.  */
 213   asection *output_section;
 214
 215   /* Offset within output section.  */
 216   bfd_vma output_offset;
 217 } lang_reloc_statement_type;
 218
 219 typedef struct lang_input_statement_struct
 220 {
 221   lang_statement_header_type header;
 222   /* Name of this file.  */
 223   const char *filename;
 224   /* Name to use for the symbol giving address of text start.
 225      Usually the same as filename, but for a file spec'd with
 226      -l this is the -l switch itself rather than the filename.  */
 227   const char *local_sym_name;
 228
 229   bfd *the_bfd;
 230
 231   file_ptr passive_position;
 232
 233   /* Symbol table of the file.  */
 234   asymbol **asymbols;
 235   unsigned int symbol_count;
 236
 237   /* Point to the next file - whatever it is, wanders up and down
 238      archives */
 239   union lang_statement_union *next;
 240
 241   /* Point to the next file, but skips archive contents.  */
 242   union lang_statement_union *next_real_file;
 243
 244   const char *target;
 245
 246   unsigned int closed : 1;
 247   unsigned int is_archive : 1;
 248
 249   /* 1 means search a set of directories for this file.  */
 250   unsigned int search_dirs_flag : 1;
 251
 252   /* 1 means this was found in a search directory marked as sysrooted,
 253      if search_dirs_flag is false, otherwise, that it should be
 254      searched in ld_sysroot before any other location, as long as it
 255      starts with a slash.  */
 256   unsigned int sysrooted : 1;
 257
 258   /* 1 means this is base file of incremental load.
 259      Do not load this file's text or data.
 260      Also default text_start to after this file's bss.  */
 261   unsigned int just_syms_flag : 1;
 262
 263   /* Whether to search for this entry as a dynamic archive.  */
 264   unsigned int dynamic : 1;
 265
 266   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 267      DT_NEEDED tags from this entry.  */
 268   unsigned int add_needed : 1;
 269
 270   /* Whether this entry should cause a DT_NEEDED tag only when
 271      satisfying references from regular files, or always.  */
 272   unsigned int as_needed : 1;
 273
 274   /* Whether to include the entire contents of an archive.  */
 275   unsigned int whole_archive : 1;
 276
 277   unsigned int loaded : 1;
 278
 279   unsigned int real : 1;
 280 } lang_input_statement_type;
 281
 282 typedef struct
 283 {
 284   lang_statement_header_type header;
 285   asection *section;
 286 } lang_input_section_type;
 287
 288 typedef struct
 289 {
 290   lang_statement_header_type header;
 291   asection *section;
 292   union lang_statement_union *file;
 293 } lang_afile_asection_pair_statement_type;
 294
 295 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 296
 297 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 298                             asection *, lang_input_statement_type *, void *);
 299
 300 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 301                                              lang_input_statement_type *,
 302                                              callback_t callback,
 303                                              void *data);
 304
 305 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 306                                                  bfd *, const asection *);
 307
 308 struct lang_wild_statement_struct
 309 {
 310   lang_statement_header_type header;
 311   const char *filename;
 312   bfd_boolean filenames_sorted;
 313   struct wildcard_list *section_list;
 314   bfd_boolean keep_sections;
 315   lang_statement_list_type children;
 316
 317   walk_wild_section_handler_t walk_wild_section_handler;
 318   struct wildcard_list *handler_data[4];
 319 };
 320
 321 typedef struct lang_address_statement_struct
 322 {
 323   lang_statement_header_type header;
 324   const char *section_name;
 325   union etree_union *address;
 326   const segment_type *segment;
 327 } lang_address_statement_type;
 328
 329 typedef struct
 330 {
 331   lang_statement_header_type header;
 332   bfd_vma output_offset;
 333   size_t size;
 334   asection *output_section;
 335   fill_type *fill;
 336 } lang_padding_statement_type;
 337
 338 /* A group statement collects a set of libraries together.  The
 339    libraries are searched multiple times, until no new undefined
 340    symbols are found.  The effect is to search a group of libraries as
 341    though they were a single library.  */
 342
 343 typedef struct
 344 {
 345   lang_statement_header_type header;
 346   lang_statement_list_type children;
 347 } lang_group_statement_type;
 348
 349 typedef union lang_statement_union
 350 {
 351   lang_statement_header_type header;
 352   lang_wild_statement_type wild_statement;
 353   lang_data_statement_type data_statement;
 354   lang_reloc_statement_type reloc_statement;
 355   lang_address_statement_type address_statement;
 356   lang_output_section_statement_type output_section_statement;
 357   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 358   lang_assignment_statement_type assignment_statement;
 359   lang_input_statement_type input_statement;
 360   lang_target_statement_type target_statement;
 361   lang_output_statement_type output_statement;
 362   lang_input_section_type input_section;
 363   lang_common_statement_type common_statement;
 364   lang_object_symbols_statement_type object_symbols_statement;
 365   lang_fill_statement_type fill_statement;
 366   lang_padding_statement_type padding_statement;
 367   lang_group_statement_type group_statement;
 368 } lang_statement_union_type;
 369
 370 /* This structure holds information about a program header, from the
 371    PHDRS command in the linker script.  */
 372
 373 struct lang_phdr
 374 {
 375   struct lang_phdr *next;
 376   const char *name;
 377   unsigned long type;
 378   bfd_boolean filehdr;
 379   bfd_boolean phdrs;
 380   etree_type *at;
 381   etree_type *flags;
 382 };
 383
 384 extern struct lang_phdr *lang_phdr_list;
 385
 386 /* This structure is used to hold a list of sections which may not
 387    cross reference each other.  */
 388
 389 typedef struct lang_nocrossref
 390 {
 391   struct lang_nocrossref *next;
 392   const char *name;
 393 } lang_nocrossref_type;
 394
 395 /* The list of nocrossref lists.  */
 396
 397 struct lang_nocrossrefs
 398 {
 399   struct lang_nocrossrefs *next;
 400   lang_nocrossref_type *list;
 401 };
 402
 403 extern struct lang_nocrossrefs *nocrossref_list;
 404
 405 /* This structure is used to hold a list of input section names which
 406    will not match an output section in the linker script.  */
 407
 408 struct unique_sections
 409 {
 410   struct unique_sections *next;
 411   const char *name;
 412 };
 413
 414 /* This structure records symbols for which we need to keep track of
 415    definedness for use in the DEFINED () test.  */
 416
 417 struct lang_definedness_hash_entry
 418 {
 419   struct bfd_hash_entry root;
 420   int iteration;
 421 };
 422
 423 /* Used by place_orphan to keep track of orphan sections and statements.  */
 424
 425 struct orphan_save {
 426   const char *name;
 427   flagword flags;
 428   lang_output_section_statement_type *os;
 429   asection **section;
 430   lang_statement_union_type **stmt;
 431   lang_output_section_statement_type **os_tail;
 432 };
 433
 434 extern lang_output_section_statement_type *abs_output_section;
 435 extern lang_statement_list_type lang_output_section_statement;
 436 extern bfd_boolean lang_has_input_file;
 437 extern etree_type *base;
 438 extern lang_statement_list_type *stat_ptr;
 439 extern bfd_boolean delete_output_file_on_failure;
 440
 441 extern struct bfd_sym_chain entry_symbol;
 442 extern const char *entry_section;
 443 extern bfd_boolean entry_from_cmdline;
 444 extern lang_statement_list_type file_chain;
 445
 446 extern int lang_statement_iteration;
 447
 448 extern void lang_init
 449   (void);
 450 extern void lang_finish
 451   (void);
 452 extern lang_memory_region_type *lang_memory_region_lookup
 453   (const char *const, bfd_boolean);
 454 extern lang_memory_region_type *lang_memory_region_default
 455   (asection *);
 456 extern void lang_map
 457   (void);
 458 extern void lang_set_flags
 459   (lang_memory_region_type *, const char *, int);
 460 extern void lang_add_output
 461   (const char *, int from_script);
 462 extern lang_output_section_statement_type *lang_enter_output_section_statement
 463   (const char *output_section_statement_name,
 464    etree_type *address_exp,
 465    enum section_type sectype,
 466    etree_type *align,
 467    etree_type *subalign,
 468    etree_type *, int);
 469 extern void lang_final
 470   (void);
 471 extern void lang_process
 472   (void);
 473 extern void lang_section_start
 474   (const char *, union etree_union *, const segment_type *);
 475 extern void lang_add_entry
 476   (const char *, bfd_boolean);
 477 extern void lang_default_entry
 478   (const char *);
 479 extern void lang_add_target
 480   (const char *);
 481 extern void lang_add_wild
 482   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 483 extern void lang_add_map
 484   (const char *);
 485 extern void lang_add_fill
 486   (fill_type *);
 487 extern lang_assignment_statement_type *lang_add_assignment
 488   (union etree_union *);
 489 extern void lang_add_attribute
 490   (enum statement_enum);
 491 extern void lang_startup
 492   (const char *);
 493 extern void lang_float
 494   (bfd_boolean);
 495 extern void lang_leave_output_section_statement
 496   (fill_type *, const char *, lang_output_section_phdr_list *,
 497    const char *);
 498 extern void lang_abs_symbol_at_end_of
 499   (const char *, const char *);
 500 extern void lang_abs_symbol_at_beginning_of
 501   (const char *, const char *);
 502 extern void lang_statement_append
 503   (lang_statement_list_type *, lang_statement_union_type *,
 504    lang_statement_union_type **);
 505 extern void lang_for_each_input_file
 506   (void (*dothis) (lang_input_statement_type *));
 507 extern void lang_for_each_file
 508   (void (*dothis) (lang_input_statement_type *));
 509 extern void lang_reset_memory_regions
 510   (void);
 511 extern void lang_do_assignments
 512   (void);
 513
 514 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 515   lang_input_statement_type *statement;                                 \
 516   for (statement = (lang_input_statement_type *) file_chain.head;       \
 517        statement != (lang_input_statement_type *) NULL;                 \
 518        statement = (lang_input_statement_type *) statement->next)       \
 519
 520 extern void lang_process
 521   (void);
 522 extern void ldlang_add_file
 523   (lang_input_statement_type *);
 524 extern lang_output_section_statement_type *lang_output_section_find
 525   (const char * const);
 526 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 527   (const asection *, lang_output_section_statement_type **,
 528    lang_match_sec_type_func);
 529 extern lang_output_section_statement_type *lang_insert_orphan
 530   (asection *, const char *, lang_output_section_statement_type *,
 531    struct orphan_save *, etree_type *, lang_statement_list_type *);
 532 extern lang_input_statement_type *lang_add_input_file
 533   (const char *, lang_input_file_enum_type, const char *);
 534 extern void lang_add_keepsyms_file
 535   (const char *);
 536 extern lang_output_section_statement_type *
 537   lang_output_section_statement_lookup
 538   (const char *const);
 539 extern void ldlang_add_undef
 540   (const char *const);
 541 extern void lang_add_output_format
 542   (const char *, const char *, const char *, int);
 543 extern void lang_list_init
 544   (lang_statement_list_type *);
 545 extern void lang_add_data
 546   (int type, union etree_union *);
 547 extern void lang_add_reloc
 548   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 549    union etree_union *);
 550 extern void lang_for_each_statement
 551   (void (*) (lang_statement_union_type *));
 552 extern void *stat_alloc
 553   (size_t);
 554 extern void strip_excluded_output_sections
 555   (void);
 556 extern void dprint_statement
 557   (lang_statement_union_type *, int);
 558 extern void lang_size_sections
 559   (bfd_boolean *, bfd_boolean);
 560 extern void one_lang_size_sections_pass
 561   (bfd_boolean *, bfd_boolean);
 562 extern void lang_enter_group
 563   (void);
 564 extern void lang_leave_group
 565   (void);
 566 extern void lang_add_section
 567   (lang_statement_list_type *, asection *,
 568    lang_output_section_statement_type *);
 569 extern void lang_new_phdr
 570   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 571    etree_type *);
 572 extern void lang_add_nocrossref
 573   (lang_nocrossref_type *);
 574 extern void lang_enter_overlay
 575   (etree_type *, etree_type *);
 576 extern void lang_enter_overlay_section
 577   (const char *);
 578 extern void lang_leave_overlay_section
 579   (fill_type *, lang_output_section_phdr_list *);
 580 extern void lang_leave_overlay
 581   (etree_type *, int, fill_type *, const char *,
 582    lang_output_section_phdr_list *, const char *);
 583
 584 extern struct bfd_elf_version_tree *lang_elf_version_info;
 585
 586 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 587   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 588 extern struct bfd_elf_version_tree *lang_new_vers_node
 589   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 590 extern struct bfd_elf_version_deps *lang_add_vers_depend
 591   (struct bfd_elf_version_deps *, const char *);
 592 extern void lang_register_vers_node
 593   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 594 bfd_boolean unique_section_p
 595   (const asection *);
 596 extern void lang_add_unique
 597   (const char *);
 598 extern const char *lang_get_output_target
 599   (void);
 600 extern void lang_track_definedness (const char *);
 601 extern int lang_symbol_definition_iteration (const char *);
 602 extern void lang_update_definedness
 603   (const char *, struct bfd_link_hash_entry *);
 604
 605 extern void add_excluded_libs (const char *);
 606
 607 #endif