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   struct lang_output_section_statement_struct *prev;
 134   const char *name;
 135   asection *bfd_section;
 136   lang_memory_region_type *region;
 137   lang_memory_region_type *lma_region;
 138   fill_type *fill;
 139   union etree_union *addr_tree;
 140   union etree_union *load_base;
 141
 142   /* If non-null, an expression to evaluate after setting the section's
 143      size.  The expression is evaluated inside REGION (above) with '.'
 144      set to the end of the section.  Used in the last overlay section
 145      to move '.' past all the overlaid sections.  */
 146   union etree_union *update_dot_tree;
 147
 148   lang_output_section_phdr_list *phdrs;
 149
 150   unsigned int block_value;
 151   int subsection_alignment;     /* Alignment of components.  */
 152   int section_alignment;        /* Alignment of start of section.  */
 153   int constraint;
 154   flagword flags;
 155   enum section_type sectype;
 156   unsigned int processed : 1;
 157   unsigned int all_input_readonly : 1;
 158   unsigned int ignored : 1;
 159 } lang_output_section_statement_type;
 160
 161 typedef struct
 162 {
 163   lang_statement_header_type header;
 164 } lang_common_statement_type;
 165
 166 typedef struct
 167 {
 168   lang_statement_header_type header;
 169 } lang_object_symbols_statement_type;
 170
 171 typedef struct
 172 {
 173   lang_statement_header_type header;
 174   fill_type *fill;
 175   int size;
 176   asection *output_section;
 177 } lang_fill_statement_type;
 178
 179 typedef struct
 180 {
 181   lang_statement_header_type header;
 182   unsigned int type;
 183   union etree_union *exp;
 184   bfd_vma value;
 185   asection *output_section;
 186   bfd_vma output_offset;
 187 } lang_data_statement_type;
 188
 189 /* Generate a reloc in the output file.  */
 190
 191 typedef struct
 192 {
 193   lang_statement_header_type header;
 194
 195   /* Reloc to generate.  */
 196   bfd_reloc_code_real_type reloc;
 197
 198   /* Reloc howto structure.  */
 199   reloc_howto_type *howto;
 200
 201   /* Section to generate reloc against.
 202      Exactly one of section and name must be NULL.  */
 203   asection *section;
 204
 205   /* Name of symbol to generate reloc against.
 206      Exactly one of section and name must be NULL.  */
 207   const char *name;
 208
 209   /* Expression for addend.  */
 210   union etree_union *addend_exp;
 211
 212   /* Resolved addend.  */
 213   bfd_vma addend_value;
 214
 215   /* Output section where reloc should be performed.  */
 216   asection *output_section;
 217
 218   /* Offset within output section.  */
 219   bfd_vma output_offset;
 220 } lang_reloc_statement_type;
 221
 222 typedef struct lang_input_statement_struct
 223 {
 224   lang_statement_header_type header;
 225   /* Name of this file.  */
 226   const char *filename;
 227   /* Name to use for the symbol giving address of text start.
 228      Usually the same as filename, but for a file spec'd with
 229      -l this is the -l switch itself rather than the filename.  */
 230   const char *local_sym_name;
 231
 232   bfd *the_bfd;
 233
 234   bfd_boolean closed;
 235   file_ptr passive_position;
 236
 237   /* Symbol table of the file.  */
 238   asymbol **asymbols;
 239   unsigned int symbol_count;
 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   bfd_boolean is_archive;
 249
 250   /* 1 means search a set of directories for this file.  */
 251   bfd_boolean search_dirs_flag;
 252
 253   /* 1 means this was found in a search directory marked as sysrooted,
 254      if search_dirs_flag is false, otherwise, that it should be
 255      searched in ld_sysroot before any other location, as long as it
 256      starts with a slash.  */
 257   bfd_boolean sysrooted;
 258
 259   /* 1 means this is base file of incremental load.
 260      Do not load this file's text or data.
 261      Also default text_start to after this file's bss.  */
 262   bfd_boolean just_syms_flag;
 263
 264   /* Whether to search for this entry as a dynamic archive.  */
 265   bfd_boolean dynamic;
 266
 267   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 268      DT_NEEDED tags from this entry.  */
 269   bfd_boolean add_needed;
 270
 271   /* Whether this entry should cause a DT_NEEDED tag only when
 272      satisfying references from regular files, or always.  */
 273   bfd_boolean as_needed;
 274
 275   /* Whether to include the entire contents of an archive.  */
 276   bfd_boolean whole_archive;
 277
 278   bfd_boolean loaded;
 279
 280   const char *target;
 281   bfd_boolean real;
 282 } lang_input_statement_type;
 283
 284 typedef struct
 285 {
 286   lang_statement_header_type header;
 287   asection *section;
 288 } lang_input_section_type;
 289
 290 typedef struct
 291 {
 292   lang_statement_header_type header;
 293   asection *section;
 294   union lang_statement_union *file;
 295 } lang_afile_asection_pair_statement_type;
 296
 297 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 298
 299 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 300                             asection *, lang_input_statement_type *, void *);
 301
 302 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 303                                              lang_input_statement_type *,
 304                                              callback_t callback,
 305                                              void *data);
 306
 307 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 308                                                  bfd *, const asection *);
 309
 310 struct lang_wild_statement_struct
 311 {
 312   lang_statement_header_type header;
 313   const char *filename;
 314   bfd_boolean filenames_sorted;
 315   struct wildcard_list *section_list;
 316   bfd_boolean keep_sections;
 317   lang_statement_list_type children;
 318
 319   walk_wild_section_handler_t walk_wild_section_handler;
 320   struct wildcard_list *handler_data[4];
 321 };
 322
 323 typedef struct lang_address_statement_struct
 324 {
 325   lang_statement_header_type header;
 326   const char *section_name;
 327   union etree_union *address;
 328   const segment_type *segment;
 329 } lang_address_statement_type;
 330
 331 typedef struct
 332 {
 333   lang_statement_header_type header;
 334   bfd_vma output_offset;
 335   size_t size;
 336   asection *output_section;
 337   fill_type *fill;
 338 } lang_padding_statement_type;
 339
 340 /* A group statement collects a set of libraries together.  The
 341    libraries are searched multiple times, until no new undefined
 342    symbols are found.  The effect is to search a group of libraries as
 343    though they were a single library.  */
 344
 345 typedef struct
 346 {
 347   lang_statement_header_type header;
 348   lang_statement_list_type children;
 349 } lang_group_statement_type;
 350
 351 typedef union lang_statement_union
 352 {
 353   lang_statement_header_type header;
 354   lang_wild_statement_type wild_statement;
 355   lang_data_statement_type data_statement;
 356   lang_reloc_statement_type reloc_statement;
 357   lang_address_statement_type address_statement;
 358   lang_output_section_statement_type output_section_statement;
 359   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 360   lang_assignment_statement_type assignment_statement;
 361   lang_input_statement_type input_statement;
 362   lang_target_statement_type target_statement;
 363   lang_output_statement_type output_statement;
 364   lang_input_section_type input_section;
 365   lang_common_statement_type common_statement;
 366   lang_object_symbols_statement_type object_symbols_statement;
 367   lang_fill_statement_type fill_statement;
 368   lang_padding_statement_type padding_statement;
 369   lang_group_statement_type group_statement;
 370 } lang_statement_union_type;
 371
 372 /* This structure holds information about a program header, from the
 373    PHDRS command in the linker script.  */
 374
 375 struct lang_phdr
 376 {
 377   struct lang_phdr *next;
 378   const char *name;
 379   unsigned long type;
 380   bfd_boolean filehdr;
 381   bfd_boolean phdrs;
 382   etree_type *at;
 383   etree_type *flags;
 384 };
 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