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   bfd_boolean closed;
 232   file_ptr passive_position;
 233
 234   /* Symbol table of the file.  */
 235   asymbol **asymbols;
 236   unsigned int symbol_count;
 237
 238   /* Point to the next file - whatever it is, wanders up and down
 239      archives */
 240   union lang_statement_union *next;
 241
 242   /* Point to the next file, but skips archive contents.  */
 243   union lang_statement_union *next_real_file;
 244
 245   bfd_boolean is_archive;
 246
 247   /* 1 means search a set of directories for this file.  */
 248   bfd_boolean search_dirs_flag;
 249
 250   /* 1 means this was found in a search directory marked as sysrooted,
 251      if search_dirs_flag is false, otherwise, that it should be
 252      searched in ld_sysroot before any other location, as long as it
 253      starts with a slash.  */
 254   bfd_boolean sysrooted;
 255
 256   /* 1 means this is base file of incremental load.
 257      Do not load this file's text or data.
 258      Also default text_start to after this file's bss.  */
 259   bfd_boolean just_syms_flag;
 260
 261   /* Whether to search for this entry as a dynamic archive.  */
 262   bfd_boolean dynamic;
 263
 264   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 265      DT_NEEDED tags from this entry.  */
 266   bfd_boolean add_needed;
 267
 268   /* Whether this entry should cause a DT_NEEDED tag only when
 269      satisfying references from regular files, or always.  */
 270   bfd_boolean as_needed;
 271
 272   /* Whether to include the entire contents of an archive.  */
 273   bfd_boolean whole_archive;
 274
 275   bfd_boolean loaded;
 276
 277   const char *target;
 278   bfd_boolean real;
 279 } lang_input_statement_type;
 280
 281 typedef struct
 282 {
 283   lang_statement_header_type header;
 284   asection *section;
 285 } lang_input_section_type;
 286
 287 typedef struct
 288 {
 289   lang_statement_header_type header;
 290   asection *section;
 291   union lang_statement_union *file;
 292 } lang_afile_asection_pair_statement_type;
 293
 294 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 295
 296 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 297                             asection *, lang_input_statement_type *, void *);
 298
 299 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 300                                              lang_input_statement_type *,
 301                                              callback_t callback,
 302                                              void *data);
 303
 304 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 305                                                  bfd *, const asection *);
 306
 307 struct lang_wild_statement_struct
 308 {
 309   lang_statement_header_type header;
 310   const char *filename;
 311   bfd_boolean filenames_sorted;
 312   struct wildcard_list *section_list;
 313   bfd_boolean keep_sections;
 314   lang_statement_list_type children;
 315
 316   walk_wild_section_handler_t walk_wild_section_handler;
 317   struct wildcard_list *handler_data[4];
 318 };
 319
 320 typedef struct lang_address_statement_struct
 321 {
 322   lang_statement_header_type header;
 323   const char *section_name;
 324   union etree_union *address;
 325   const segment_type *segment;
 326 } lang_address_statement_type;
 327
 328 typedef struct
 329 {
 330   lang_statement_header_type header;
 331   bfd_vma output_offset;
 332   size_t size;
 333   asection *output_section;
 334   fill_type *fill;
 335 } lang_padding_statement_type;
 336
 337 /* A group statement collects a set of libraries together.  The
 338    libraries are searched multiple times, until no new undefined
 339    symbols are found.  The effect is to search a group of libraries as
 340    though they were a single library.  */
 341
 342 typedef struct
 343 {
 344   lang_statement_header_type header;
 345   lang_statement_list_type children;
 346 } lang_group_statement_type;
 347
 348 typedef union lang_statement_union
 349 {
 350   lang_statement_header_type header;
 351   lang_wild_statement_type wild_statement;
 352   lang_data_statement_type data_statement;
 353   lang_reloc_statement_type reloc_statement;
 354   lang_address_statement_type address_statement;
 355   lang_output_section_statement_type output_section_statement;
 356   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 357   lang_assignment_statement_type assignment_statement;
 358   lang_input_statement_type input_statement;
 359   lang_target_statement_type target_statement;
 360   lang_output_statement_type output_statement;
 361   lang_input_section_type input_section;
 362   lang_common_statement_type common_statement;
 363   lang_object_symbols_statement_type object_symbols_statement;
 364   lang_fill_statement_type fill_statement;
 365   lang_padding_statement_type padding_statement;
 366   lang_group_statement_type group_statement;
 367 } lang_statement_union_type;
 368
 369 /* This structure holds information about a program header, from the
 370    PHDRS command in the linker script.  */
 371
 372 struct lang_phdr
 373 {
 374   struct lang_phdr *next;
 375   const char *name;
 376   unsigned long type;
 377   bfd_boolean filehdr;
 378   bfd_boolean phdrs;
 379   etree_type *at;
 380   etree_type *flags;
 381 };
 382
 383 /* This structure is used to hold a list of sections which may not
 384    cross reference each other.  */
 385
 386 typedef struct lang_nocrossref
 387 {
 388   struct lang_nocrossref *next;
 389   const char *name;
 390 } lang_nocrossref_type;
 391
 392 /* The list of nocrossref lists.  */
 393
 394 struct lang_nocrossrefs
 395 {
 396   struct lang_nocrossrefs *next;
 397   lang_nocrossref_type *list;
 398 };
 399
 400 extern struct lang_nocrossrefs *nocrossref_list;
 401
 402 /* This structure is used to hold a list of input section names which
 403    will not match an output section in the linker script.  */
 404
 405 struct unique_sections
 406 {
 407   struct unique_sections *next;
 408   const char *name;
 409 };
 410
 411 /* This structure records symbols for which we need to keep track of
 412    definedness for use in the DEFINED () test.  */
 413
 414 struct lang_definedness_hash_entry
 415 {
 416   struct bfd_hash_entry root;
 417   int iteration;
 418 };
 419
 420 /* Used by place_orphan to keep track of orphan sections and statements.  */
 421
 422 struct orphan_save {
 423   const char *name;
 424   flagword flags;
 425   lang_output_section_statement_type *os;
 426   asection **section;
 427   lang_statement_union_type **stmt;
 428   lang_output_section_statement_type **os_tail;
 429 };
 430
 431 extern lang_output_section_statement_type *abs_output_section;
 432 extern lang_statement_list_type lang_output_section_statement;
 433 extern bfd_boolean lang_has_input_file;
 434 extern etree_type *base;
 435 extern lang_statement_list_type *stat_ptr;
 436 extern bfd_boolean delete_output_file_on_failure;
 437
 438 extern struct bfd_sym_chain entry_symbol;
 439 extern const char *entry_section;
 440 extern bfd_boolean entry_from_cmdline;
 441 extern lang_statement_list_type file_chain;
 442
 443 extern int lang_statement_iteration;
 444
 445 extern void lang_init
 446   (void);
 447 extern void lang_finish
 448   (void);
 449 extern lang_memory_region_type *lang_memory_region_lookup
 450   (const char *const, bfd_boolean);
 451 extern lang_memory_region_type *lang_memory_region_default
 452   (asection *);
 453 extern void lang_map
 454   (void);
 455 extern void lang_set_flags
 456   (lang_memory_region_type *, const char *, int);
 457 extern void lang_add_output
 458   (const char *, int from_script);
 459 extern lang_output_section_statement_type *lang_enter_output_section_statement
 460   (const char *output_section_statement_name,
 461    etree_type *address_exp,
 462    enum section_type sectype,
 463    etree_type *align,
 464    etree_type *subalign,
 465    etree_type *, int);
 466 extern void lang_final
 467   (void);
 468 extern void lang_process
 469   (void);
 470 extern void lang_section_start
 471   (const char *, union etree_union *, const segment_type *);
 472 extern void lang_add_entry
 473   (const char *, bfd_boolean);
 474 extern void lang_default_entry
 475   (const char *);
 476 extern void lang_add_target
 477   (const char *);
 478 extern void lang_add_wild
 479   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 480 extern void lang_add_map
 481   (const char *);
 482 extern void lang_add_fill
 483   (fill_type *);
 484 extern lang_assignment_statement_type *lang_add_assignment
 485   (union etree_union *);
 486 extern void lang_add_attribute
 487   (enum statement_enum);
 488 extern void lang_startup
 489   (const char *);
 490 extern void lang_float
 491   (bfd_boolean);
 492 extern void lang_leave_output_section_statement
 493   (fill_type *, const char *, lang_output_section_phdr_list *,
 494    const char *);
 495 extern void lang_abs_symbol_at_end_of
 496   (const char *, const char *);
 497 extern void lang_abs_symbol_at_beginning_of
 498   (const char *, const char *);
 499 extern void lang_statement_append
 500   (lang_statement_list_type *, lang_statement_union_type *,
 501    lang_statement_union_type **);
 502 extern void lang_for_each_input_file
 503   (void (*dothis) (lang_input_statement_type *));
 504 extern void lang_for_each_file
 505   (void (*dothis) (lang_input_statement_type *));
 506 extern void lang_reset_memory_regions
 507   (void);
 508 extern void lang_do_assignments
 509   (void);
 510
 511 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 512   lang_input_statement_type *statement;                                 \
 513   for (statement = (lang_input_statement_type *) file_chain.head;       \
 514        statement != (lang_input_statement_type *) NULL;                 \
 515        statement = (lang_input_statement_type *) statement->next)       \
 516
 517 extern void lang_process
 518   (void);
 519 extern void ldlang_add_file
 520   (lang_input_statement_type *);
 521 extern lang_output_section_statement_type *lang_output_section_find
 522   (const char * const);
 523 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 524   (const asection *, lang_output_section_statement_type **,
 525    lang_match_sec_type_func);
 526 extern lang_output_section_statement_type *lang_insert_orphan
 527   (asection *, const char *, lang_output_section_statement_type *,
 528    struct orphan_save *, etree_type *, lang_statement_list_type *);
 529 extern lang_input_statement_type *lang_add_input_file
 530   (const char *, lang_input_file_enum_type, const char *);
 531 extern void lang_add_keepsyms_file
 532   (const char *);
 533 extern lang_output_section_statement_type *
 534   lang_output_section_statement_lookup
 535   (const char *const);
 536 extern void ldlang_add_undef
 537   (const char *const);
 538 extern void lang_add_output_format
 539   (const char *, const char *, const char *, int);
 540 extern void lang_list_init
 541   (lang_statement_list_type *);
 542 extern void lang_add_data
 543   (int type, union etree_union *);
 544 extern void lang_add_reloc
 545   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 546    union etree_union *);
 547 extern void lang_for_each_statement
 548   (void (*) (lang_statement_union_type *));
 549 extern void *stat_alloc
 550   (size_t);
 551 extern void strip_excluded_output_sections
 552   (void);
 553 extern void dprint_statement
 554   (lang_statement_union_type *, int);
 555 extern void lang_size_sections
 556   (bfd_boolean *, bfd_boolean);
 557 extern void one_lang_size_sections_pass
 558   (bfd_boolean *, bfd_boolean);
 559 extern void lang_enter_group
 560   (void);
 561 extern void lang_leave_group
 562   (void);
 563 extern void lang_add_section
 564   (lang_statement_list_type *, asection *,
 565    lang_output_section_statement_type *);
 566 extern void lang_new_phdr
 567   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 568    etree_type *);
 569 extern void lang_add_nocrossref
 570   (lang_nocrossref_type *);
 571 extern void lang_enter_overlay
 572   (etree_type *, etree_type *);
 573 extern void lang_enter_overlay_section
 574   (const char *);
 575 extern void lang_leave_overlay_section
 576   (fill_type *, lang_output_section_phdr_list *);
 577 extern void lang_leave_overlay
 578   (etree_type *, int, fill_type *, const char *,
 579    lang_output_section_phdr_list *, const char *);
 580
 581 extern struct bfd_elf_version_tree *lang_elf_version_info;
 582
 583 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 584   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 585 extern struct bfd_elf_version_tree *lang_new_vers_node
 586   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 587 extern struct bfd_elf_version_deps *lang_add_vers_depend
 588   (struct bfd_elf_version_deps *, const char *);
 589 extern void lang_register_vers_node
 590   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 591 bfd_boolean unique_section_p
 592   (const asection *);
 593 extern void lang_add_unique
 594   (const char *);
 595 extern const char *lang_get_output_target
 596   (void);
 597 extern void lang_track_definedness (const char *);
 598 extern int lang_symbol_definition_iteration (const char *);
 599 extern void lang_update_definedness
 600   (const char *, struct bfd_link_hash_entry *);
 601
 602 extern void add_excluded_libs (const char *);
 603
 604 #endif