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
   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   dsect_section,
 112   copy_section,
 113   noload_section,
 114   info_section,
 115   overlay_section
 116 };
 117
 118 /* This structure holds a list of program headers describing
 119    segments in which this section should be placed.  */
 120
 121 typedef struct lang_output_section_phdr_list
 122 {
 123   struct lang_output_section_phdr_list *next;
 124   const char *name;
 125   bfd_boolean used;
 126 } lang_output_section_phdr_list;
 127
 128 typedef struct lang_output_section_statement_struct
 129 {
 130   lang_statement_header_type header;
 131   lang_statement_list_type children;
 132   struct lang_output_section_statement_struct *next;
 133   const char *name;
 134   asection *bfd_section;
 135   lang_memory_region_type *region;
 136   lang_memory_region_type *lma_region;
 137   fill_type *fill;
 138   union etree_union *addr_tree;
 139   union etree_union *load_base;
 140
 141   /* If non-null, an expression to evaluate after setting the section's
 142      size.  The expression is evaluated inside REGION (above) with '.'
 143      set to the end of the section.  Used in the last overlay section
 144      to move '.' past all the overlaid sections.  */
 145   union etree_union *update_dot_tree;
 146
 147   lang_output_section_phdr_list *phdrs;
 148
 149   unsigned int block_value;
 150   int subsection_alignment;     /* Alignment of components.  */
 151   int section_alignment;        /* Alignment of start of section.  */
 152   int constraint;
 153   flagword flags;
 154   enum section_type sectype;
 155   unsigned int processed : 1;
 156   unsigned int all_input_readonly : 1;
 157   unsigned int ignored : 1;
 158 } lang_output_section_statement_type;
 159
 160 typedef struct
 161 {
 162   lang_statement_header_type header;
 163 } lang_common_statement_type;
 164
 165 typedef struct
 166 {
 167   lang_statement_header_type header;
 168 } lang_object_symbols_statement_type;
 169
 170 typedef struct
 171 {
 172   lang_statement_header_type header;
 173   fill_type *fill;
 174   int size;
 175   asection *output_section;
 176 } lang_fill_statement_type;
 177
 178 typedef struct
 179 {
 180   lang_statement_header_type header;
 181   unsigned int type;
 182   union etree_union *exp;
 183   bfd_vma value;
 184   asection *output_section;
 185   bfd_vma output_offset;
 186 } lang_data_statement_type;
 187
 188 /* Generate a reloc in the output file.  */
 189
 190 typedef struct
 191 {
 192   lang_statement_header_type header;
 193
 194   /* Reloc to generate.  */
 195   bfd_reloc_code_real_type reloc;
 196
 197   /* Reloc howto structure.  */
 198   reloc_howto_type *howto;
 199
 200   /* Section to generate reloc against.
 201      Exactly one of section and name must be NULL.  */
 202   asection *section;
 203
 204   /* Name of symbol to generate reloc against.
 205      Exactly one of section and name must be NULL.  */
 206   const char *name;
 207
 208   /* Expression for addend.  */
 209   union etree_union *addend_exp;
 210
 211   /* Resolved addend.  */
 212   bfd_vma addend_value;
 213
 214   /* Output section where reloc should be performed.  */
 215   asection *output_section;
 216
 217   /* Offset within output section.  */
 218   bfd_vma output_offset;
 219 } lang_reloc_statement_type;
 220
 221 typedef struct lang_input_statement_struct
 222 {
 223   lang_statement_header_type header;
 224   /* Name of this file.  */
 225   const char *filename;
 226   /* Name to use for the symbol giving address of text start.
 227      Usually the same as filename, but for a file spec'd with
 228      -l this is the -l switch itself rather than the filename.  */
 229   const char *local_sym_name;
 230
 231   bfd *the_bfd;
 232
 233   bfd_boolean closed;
 234   file_ptr passive_position;
 235
 236   /* Symbol table of the file.  */
 237   asymbol **asymbols;
 238   unsigned int symbol_count;
 239
 240   /* Point to the next file - whatever it is, wanders up and down
 241      archives */
 242   union lang_statement_union *next;
 243
 244   /* Point to the next file, but skips archive contents.  */
 245   union lang_statement_union *next_real_file;
 246
 247   bfd_boolean is_archive;
 248
 249   /* 1 means search a set of directories for this file.  */
 250   bfd_boolean search_dirs_flag;
 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   bfd_boolean sysrooted;
 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   bfd_boolean just_syms_flag;
 262
 263   /* Whether to search for this entry as a dynamic archive.  */
 264   bfd_boolean dynamic;
 265
 266   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 267      DT_NEEDED tags from this entry.  */
 268   bfd_boolean add_needed;
 269
 270   /* Whether this entry should cause a DT_NEEDED tag only when
 271      satisfying references from regular files, or always.  */
 272   bfd_boolean as_needed;
 273
 274   /* Whether to include the entire contents of an archive.  */
 275   bfd_boolean whole_archive;
 276
 277   bfd_boolean loaded;
 278
 279   const char *target;
 280   bfd_boolean real;
 281 } lang_input_statement_type;
 282
 283 typedef struct
 284 {
 285   lang_statement_header_type header;
 286   asection *section;
 287   lang_input_statement_type *ifile;
 288
 289 } lang_input_section_type;
 290
 291 typedef struct
 292 {
 293   lang_statement_header_type header;
 294   asection *section;
 295   union lang_statement_union *file;
 296 } lang_afile_asection_pair_statement_type;
 297
 298 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 299
 300 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 301                             asection *, lang_input_statement_type *, void *);
 302
 303 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 304                                              lang_input_statement_type *,
 305                                              callback_t callback,
 306                                              void *data);
 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 /* This structure is used to hold a list of sections which may not
 385    cross reference each other.  */
 386
 387 typedef struct lang_nocrossref
 388 {
 389   struct lang_nocrossref *next;
 390   const char *name;
 391 } lang_nocrossref_type;
 392
 393 /* The list of nocrossref lists.  */
 394
 395 struct lang_nocrossrefs
 396 {
 397   struct lang_nocrossrefs *next;
 398   lang_nocrossref_type *list;
 399 };
 400
 401 extern struct lang_nocrossrefs *nocrossref_list;
 402
 403 /* This structure is used to hold a list of input section names which
 404    will not match an output section in the linker script.  */
 405
 406 struct unique_sections
 407 {
 408   struct unique_sections *next;
 409   const char *name;
 410 };
 411
 412 /* This structure records symbols for which we need to keep track of
 413    definedness for use in the DEFINED () test.  */
 414
 415 struct lang_definedness_hash_entry
 416 {
 417   struct bfd_hash_entry root;
 418   int iteration;
 419 };
 420
 421 /* Used by place_orphan to keep track of orphan sections and statements.  */
 422
 423 struct orphan_save {
 424   const char *name;
 425   flagword flags;
 426   lang_output_section_statement_type *os;
 427   asection **section;
 428   lang_statement_union_type **stmt;
 429   lang_output_section_statement_type **os_tail;
 430 };
 431
 432 extern lang_output_section_statement_type *abs_output_section;
 433 extern lang_statement_list_type lang_output_section_statement;
 434 extern bfd_boolean lang_has_input_file;
 435 extern etree_type *base;
 436 extern lang_statement_list_type *stat_ptr;
 437 extern bfd_boolean delete_output_file_on_failure;
 438
 439 extern struct bfd_sym_chain entry_symbol;
 440 extern const char *entry_section;
 441 extern bfd_boolean entry_from_cmdline;
 442 extern lang_statement_list_type file_chain;
 443
 444 extern int lang_statement_iteration;
 445
 446 extern void lang_init
 447   (void);
 448 extern void lang_finish
 449   (void);
 450 extern lang_memory_region_type *lang_memory_region_lookup
 451   (const char *const, bfd_boolean);
 452 extern lang_memory_region_type *lang_memory_region_default
 453   (asection *);
 454 extern void lang_map
 455   (void);
 456 extern void lang_set_flags
 457   (lang_memory_region_type *, const char *, int);
 458 extern void lang_add_output
 459   (const char *, int from_script);
 460 extern lang_output_section_statement_type *lang_enter_output_section_statement
 461   (const char *output_section_statement_name,
 462    etree_type *address_exp,
 463    enum section_type sectype,
 464    etree_type *align,
 465    etree_type *subalign,
 466    etree_type *, int);
 467 extern void lang_final
 468   (void);
 469 extern void lang_process
 470   (void);
 471 extern void lang_section_start
 472   (const char *, union etree_union *, const segment_type *);
 473 extern void lang_add_entry
 474   (const char *, bfd_boolean);
 475 extern void lang_default_entry
 476   (const char *);
 477 extern void lang_add_target
 478   (const char *);
 479 extern void lang_add_wild
 480   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 481 extern void lang_add_map
 482   (const char *);
 483 extern void lang_add_fill
 484   (fill_type *);
 485 extern lang_assignment_statement_type *lang_add_assignment
 486   (union etree_union *);
 487 extern void lang_add_attribute
 488   (enum statement_enum);
 489 extern void lang_startup
 490   (const char *);
 491 extern void lang_float
 492   (bfd_boolean);
 493 extern void lang_leave_output_section_statement
 494   (fill_type *, const char *, lang_output_section_phdr_list *,
 495    const char *);
 496 extern void lang_abs_symbol_at_end_of
 497   (const char *, const char *);
 498 extern void lang_abs_symbol_at_beginning_of
 499   (const char *, const char *);
 500 extern void lang_statement_append
 501   (lang_statement_list_type *, lang_statement_union_type *,
 502    lang_statement_union_type **);
 503 extern void lang_for_each_input_file
 504   (void (*dothis) (lang_input_statement_type *));
 505 extern void lang_for_each_file
 506   (void (*dothis) (lang_input_statement_type *));
 507 extern void lang_reset_memory_regions
 508   (void);
 509 extern void lang_do_assignments
 510   (void);
 511
 512 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 513   lang_input_statement_type *statement;                                 \
 514   for (statement = (lang_input_statement_type *) file_chain.head;       \
 515        statement != (lang_input_statement_type *) NULL;                 \
 516        statement = (lang_input_statement_type *) statement->next)       \
 517
 518 extern void lang_process
 519   (void);
 520 extern void ldlang_add_file
 521   (lang_input_statement_type *);
 522 extern lang_output_section_statement_type *lang_output_section_find
 523   (const char * const);
 524 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 525   (const asection *, lang_output_section_statement_type **exact);
 526 extern lang_output_section_statement_type *lang_insert_orphan
 527   (lang_input_statement_type *, asection *, const char *,
 528    lang_output_section_statement_type *, struct orphan_save *,
 529    etree_type *, lang_statement_list_type *);
 530 extern lang_input_statement_type *lang_add_input_file
 531   (const char *, lang_input_file_enum_type, const char *);
 532 extern void lang_add_keepsyms_file
 533   (const char *);
 534 extern lang_output_section_statement_type *
 535   lang_output_section_statement_lookup
 536   (const char *const);
 537 extern void ldlang_add_undef
 538   (const char *const);
 539 extern void lang_add_output_format
 540   (const char *, const char *, const char *, int);
 541 extern void lang_list_init
 542   (lang_statement_list_type *);
 543 extern void lang_add_data
 544   (int type, union etree_union *);
 545 extern void lang_add_reloc
 546   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 547    union etree_union *);
 548 extern void lang_for_each_statement
 549   (void (*) (lang_statement_union_type *));
 550 extern void *stat_alloc
 551   (size_t);
 552 extern void strip_excluded_output_sections
 553   (void);
 554 extern void dprint_statement
 555   (lang_statement_union_type *, int);
 556 extern void lang_size_sections
 557   (bfd_boolean *, bfd_boolean);
 558 extern void one_lang_size_sections_pass
 559   (bfd_boolean *, bfd_boolean);
 560 extern void lang_enter_group
 561   (void);
 562 extern void lang_leave_group
 563   (void);
 564 extern void lang_add_section
 565   (lang_statement_list_type *, asection *,
 566    lang_output_section_statement_type *, lang_input_statement_type *);
 567 extern void lang_new_phdr
 568   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 569    etree_type *);
 570 extern void lang_add_nocrossref
 571   (lang_nocrossref_type *);
 572 extern void lang_enter_overlay
 573   (etree_type *, etree_type *);
 574 extern void lang_enter_overlay_section
 575   (const char *);
 576 extern void lang_leave_overlay_section
 577   (fill_type *, lang_output_section_phdr_list *);
 578 extern void lang_leave_overlay
 579   (etree_type *, int, fill_type *, const char *,
 580    lang_output_section_phdr_list *, const char *);
 581
 582 extern struct bfd_elf_version_tree *lang_elf_version_info;
 583
 584 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 585   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 586 extern struct bfd_elf_version_tree *lang_new_vers_node
 587   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 588 extern struct bfd_elf_version_deps *lang_add_vers_depend
 589   (struct bfd_elf_version_deps *, const char *);
 590 extern void lang_register_vers_node
 591   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 592 bfd_boolean unique_section_p
 593   (const asection *);
 594 extern void lang_add_unique
 595   (const char *);
 596 extern const char *lang_get_output_target
 597   (void);
 598 extern void lang_track_definedness (const char *);
 599 extern int lang_symbol_definition_iteration (const char *);
 600 extern void lang_update_definedness
 601   (const char *, struct bfd_link_hash_entry *);
 602
 603 extern void add_excluded_libs (const char *);
 604
 605 #endif