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   union etree_union *addr_tree;
 132   lang_statement_list_type children;
 133   const char *memspec;
 134   struct lang_output_section_statement_struct *next;
 135   const char *name;
 136
 137   int processed;
 138
 139   asection *bfd_section;
 140   flagword flags;               /* Or together of all input sections.  */
 141   enum section_type sectype;
 142   lang_memory_region_type *region;
 143   lang_memory_region_type *lma_region;
 144   size_t block_value;
 145   fill_type *fill;
 146
 147   int subsection_alignment;     /* Alignment of components.  */
 148   int section_alignment;        /* Alignment of start of section.  */
 149   int constraint;
 150   unsigned int all_input_readonly : 1;
 151   unsigned int ignored : 1;
 152
 153   union etree_union *load_base;
 154
 155   /* If non-null, an expression to evaluate after setting the section's
 156      size.  The expression is evaluated inside REGION (above) with '.'
 157      set to the end of the section.  Used in the last overlay section
 158      to move '.' past all the overlaid sections.  */
 159   union etree_union *update_dot_tree;
 160
 161   lang_output_section_phdr_list *phdrs;
 162 } lang_output_section_statement_type;
 163
 164 typedef struct
 165 {
 166   lang_statement_header_type header;
 167 } lang_common_statement_type;
 168
 169 typedef struct
 170 {
 171   lang_statement_header_type header;
 172 } lang_object_symbols_statement_type;
 173
 174 typedef struct
 175 {
 176   lang_statement_header_type header;
 177   fill_type *fill;
 178   int size;
 179   asection *output_section;
 180 } lang_fill_statement_type;
 181
 182 typedef struct
 183 {
 184   lang_statement_header_type header;
 185   unsigned int type;
 186   union etree_union *exp;
 187   bfd_vma value;
 188   asection *output_section;
 189   bfd_vma output_vma;
 190 } lang_data_statement_type;
 191
 192 /* Generate a reloc in the output file.  */
 193
 194 typedef struct
 195 {
 196   lang_statement_header_type header;
 197
 198   /* Reloc to generate.  */
 199   bfd_reloc_code_real_type reloc;
 200
 201   /* Reloc howto structure.  */
 202   reloc_howto_type *howto;
 203
 204   /* Section to generate reloc against.
 205      Exactly one of section and name must be NULL.  */
 206   asection *section;
 207
 208   /* Name of symbol to generate reloc against.
 209      Exactly one of section and name must be NULL.  */
 210   const char *name;
 211
 212   /* Expression for addend.  */
 213   union etree_union *addend_exp;
 214
 215   /* Resolved addend.  */
 216   bfd_vma addend_value;
 217
 218   /* Output section where reloc should be performed.  */
 219   asection *output_section;
 220
 221   /* VMA within output section.  */
 222   bfd_vma output_vma;
 223 } lang_reloc_statement_type;
 224
 225 typedef struct lang_input_statement_struct
 226 {
 227   lang_statement_header_type header;
 228   /* Name of this file.  */
 229   const char *filename;
 230   /* Name to use for the symbol giving address of text start.
 231      Usually the same as filename, but for a file spec'd with
 232      -l this is the -l switch itself rather than the filename.  */
 233   const char *local_sym_name;
 234
 235   bfd *the_bfd;
 236
 237   bfd_boolean closed;
 238   file_ptr passive_position;
 239
 240   /* Symbol table of the file.  */
 241   asymbol **asymbols;
 242   unsigned int symbol_count;
 243
 244   /* Point to the next file - whatever it is, wanders up and down
 245      archives */
 246   union lang_statement_union *next;
 247
 248   /* Point to the next file, but skips archive contents.  */
 249   union lang_statement_union *next_real_file;
 250
 251   bfd_boolean is_archive;
 252
 253   /* 1 means search a set of directories for this file.  */
 254   bfd_boolean search_dirs_flag;
 255
 256   /* 1 means this was found in a search directory marked as sysrooted,
 257      if search_dirs_flag is false, otherwise, that it should be
 258      searched in ld_sysroot before any other location, as long as it
 259      starts with a slash.  */
 260   bfd_boolean sysrooted;
 261
 262   /* 1 means this is base file of incremental load.
 263      Do not load this file's text or data.
 264      Also default text_start to after this file's bss.  */
 265   bfd_boolean just_syms_flag;
 266
 267   /* Whether to search for this entry as a dynamic archive.  */
 268   bfd_boolean dynamic;
 269
 270   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 271      DT_NEEDED tags from this entry.  */
 272   bfd_boolean add_needed;
 273
 274   /* Whether this entry should cause a DT_NEEDED tag only when
 275      satisfying references from regular files, or always.  */
 276   bfd_boolean as_needed;
 277
 278   /* Whether to include the entire contents of an archive.  */
 279   bfd_boolean whole_archive;
 280
 281   bfd_boolean loaded;
 282
 283   const char *target;
 284   bfd_boolean real;
 285 } lang_input_statement_type;
 286
 287 typedef struct
 288 {
 289   lang_statement_header_type header;
 290   asection *section;
 291   lang_input_statement_type *ifile;
 292
 293 } lang_input_section_type;
 294
 295 typedef struct
 296 {
 297   lang_statement_header_type header;
 298   asection *section;
 299   union lang_statement_union *file;
 300 } lang_afile_asection_pair_statement_type;
 301
 302 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 303
 304 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 305                             asection *, lang_input_statement_type *, void *);
 306
 307 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 308                                              lang_input_statement_type *,
 309                                              callback_t callback,
 310                                              void *data);
 311
 312 struct lang_wild_statement_struct
 313 {
 314   lang_statement_header_type header;
 315   const char *filename;
 316   bfd_boolean filenames_sorted;
 317   struct wildcard_list *section_list;
 318   bfd_boolean keep_sections;
 319   lang_statement_list_type children;
 320
 321   walk_wild_section_handler_t walk_wild_section_handler;
 322   struct wildcard_list *handler_data[4];
 323 };
 324
 325 typedef struct lang_address_statement_struct
 326 {
 327   lang_statement_header_type header;
 328   const char *section_name;
 329   union etree_union *address;
 330   const segment_type *segment;
 331 } lang_address_statement_type;
 332
 333 typedef struct
 334 {
 335   lang_statement_header_type header;
 336   bfd_vma output_offset;
 337   size_t size;
 338   asection *output_section;
 339   fill_type *fill;
 340 } lang_padding_statement_type;
 341
 342 /* A group statement collects a set of libraries together.  The
 343    libraries are searched multiple times, until no new undefined
 344    symbols are found.  The effect is to search a group of libraries as
 345    though they were a single library.  */
 346
 347 typedef struct
 348 {
 349   lang_statement_header_type header;
 350   lang_statement_list_type children;
 351 } lang_group_statement_type;
 352
 353 typedef union lang_statement_union
 354 {
 355   lang_statement_header_type header;
 356   lang_wild_statement_type wild_statement;
 357   lang_data_statement_type data_statement;
 358   lang_reloc_statement_type reloc_statement;
 359   lang_address_statement_type address_statement;
 360   lang_output_section_statement_type output_section_statement;
 361   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 362   lang_assignment_statement_type assignment_statement;
 363   lang_input_statement_type input_statement;
 364   lang_target_statement_type target_statement;
 365   lang_output_statement_type output_statement;
 366   lang_input_section_type input_section;
 367   lang_common_statement_type common_statement;
 368   lang_object_symbols_statement_type object_symbols_statement;
 369   lang_fill_statement_type fill_statement;
 370   lang_padding_statement_type padding_statement;
 371   lang_group_statement_type group_statement;
 372 } lang_statement_union_type;
 373
 374 /* This structure holds information about a program header, from the
 375    PHDRS command in the linker script.  */
 376
 377 struct lang_phdr
 378 {
 379   struct lang_phdr *next;
 380   const char *name;
 381   unsigned long type;
 382   bfd_boolean filehdr;
 383   bfd_boolean phdrs;
 384   etree_type *at;
 385   etree_type *flags;
 386 };
 387
 388 /* This structure is used to hold a list of sections which may not
 389    cross reference each other.  */
 390
 391 typedef struct lang_nocrossref
 392 {
 393   struct lang_nocrossref *next;
 394   const char *name;
 395 } lang_nocrossref_type;
 396
 397 /* The list of nocrossref lists.  */
 398
 399 struct lang_nocrossrefs
 400 {
 401   struct lang_nocrossrefs *next;
 402   lang_nocrossref_type *list;
 403 };
 404
 405 extern struct lang_nocrossrefs *nocrossref_list;
 406
 407 /* This structure is used to hold a list of input section names which
 408    will not match an output section in the linker script.  */
 409
 410 struct unique_sections
 411 {
 412   struct unique_sections *next;
 413   const char *name;
 414 };
 415
 416 /* This structure records symbols for which we need to keep track of
 417    definedness for use in the DEFINED () test.  */
 418
 419 struct lang_definedness_hash_entry
 420 {
 421   struct bfd_hash_entry root;
 422   int iteration;
 423 };
 424
 425 /* Used by place_orphan to keep track of orphan sections and statements.  */
 426
 427 struct orphan_save {
 428   const char *name;
 429   flagword flags;
 430   lang_output_section_statement_type *os;
 431   asection **section;
 432   lang_statement_union_type **stmt;
 433   lang_output_section_statement_type **os_tail;
 434 };
 435
 436 extern lang_output_section_statement_type *abs_output_section;
 437 extern lang_statement_list_type lang_output_section_statement;
 438 extern bfd_boolean lang_has_input_file;
 439 extern etree_type *base;
 440 extern lang_statement_list_type *stat_ptr;
 441 extern bfd_boolean delete_output_file_on_failure;
 442
 443 extern struct bfd_sym_chain entry_symbol;
 444 extern const char *entry_section;
 445 extern bfd_boolean entry_from_cmdline;
 446 extern lang_statement_list_type file_chain;
 447
 448 extern int lang_statement_iteration;
 449
 450 extern void lang_init
 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 **exact);
 528 extern lang_output_section_statement_type *lang_insert_orphan
 529   (lang_input_statement_type *, asection *, const char *,
 530    lang_output_section_statement_type *, struct orphan_save *,
 531    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 *, lang_input_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 *);
 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