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   bfd_boolean all_input_readonly;
 151
 152   union etree_union *load_base;
 153
 154   /* If non-null, an expression to evaluate after setting the section's
 155      size.  The expression is evaluated inside REGION (above) with '.'
 156      set to the end of the section.  Used in the last overlay section
 157      to move '.' past all the overlaid sections.  */
 158   union etree_union *update_dot_tree;
 159
 160   lang_output_section_phdr_list *phdrs;
 161 } lang_output_section_statement_type;
 162
 163 typedef struct
 164 {
 165   lang_statement_header_type header;
 166 } lang_common_statement_type;
 167
 168 typedef struct
 169 {
 170   lang_statement_header_type header;
 171 } lang_object_symbols_statement_type;
 172
 173 typedef struct
 174 {
 175   lang_statement_header_type header;
 176   fill_type *fill;
 177   int size;
 178   asection *output_section;
 179 } lang_fill_statement_type;
 180
 181 typedef struct
 182 {
 183   lang_statement_header_type header;
 184   unsigned int type;
 185   union etree_union *exp;
 186   bfd_vma value;
 187   asection *output_section;
 188   bfd_vma output_vma;
 189 } lang_data_statement_type;
 190
 191 /* Generate a reloc in the output file.  */
 192
 193 typedef struct
 194 {
 195   lang_statement_header_type header;
 196
 197   /* Reloc to generate.  */
 198   bfd_reloc_code_real_type reloc;
 199
 200   /* Reloc howto structure.  */
 201   reloc_howto_type *howto;
 202
 203   /* Section to generate reloc against.
 204      Exactly one of section and name must be NULL.  */
 205   asection *section;
 206
 207   /* Name of symbol to generate reloc against.
 208      Exactly one of section and name must be NULL.  */
 209   const char *name;
 210
 211   /* Expression for addend.  */
 212   union etree_union *addend_exp;
 213
 214   /* Resolved addend.  */
 215   bfd_vma addend_value;
 216
 217   /* Output section where reloc should be performed.  */
 218   asection *output_section;
 219
 220   /* VMA within output section.  */
 221   bfd_vma output_vma;
 222 } lang_reloc_statement_type;
 223
 224 typedef struct lang_input_statement_struct
 225 {
 226   lang_statement_header_type header;
 227   /* Name of this file.  */
 228   const char *filename;
 229   /* Name to use for the symbol giving address of text start.
 230      Usually the same as filename, but for a file spec'd with
 231      -l this is the -l switch itself rather than the filename.  */
 232   const char *local_sym_name;
 233
 234   bfd *the_bfd;
 235
 236   bfd_boolean closed;
 237   file_ptr passive_position;
 238
 239   /* Symbol table of the file.  */
 240   asymbol **asymbols;
 241   unsigned int symbol_count;
 242
 243   /* Point to the next file - whatever it is, wanders up and down
 244      archives */
 245   union lang_statement_union *next;
 246
 247   /* Point to the next file, but skips archive contents.  */
 248   union lang_statement_union *next_real_file;
 249
 250   bfd_boolean is_archive;
 251
 252   /* 1 means search a set of directories for this file.  */
 253   bfd_boolean search_dirs_flag;
 254
 255   /* 1 means this was found in a search directory marked as sysrooted,
 256      if search_dirs_flag is false, otherwise, that it should be
 257      searched in ld_sysroot before any other location, as long as it
 258      starts with a slash.  */
 259   bfd_boolean sysrooted;
 260
 261   /* 1 means this is base file of incremental load.
 262      Do not load this file's text or data.
 263      Also default text_start to after this file's bss.  */
 264   bfd_boolean just_syms_flag;
 265
 266   /* Whether to search for this entry as a dynamic archive.  */
 267   bfd_boolean dynamic;
 268
 269   /* Whether DT_NEEDED tags should be added for dynamic libraries in
 270      DT_NEEDED tags from this entry.  */
 271   bfd_boolean add_needed;
 272
 273   /* Whether this entry should cause a DT_NEEDED tag only when
 274      satisfying references from regular files, or always.  */
 275   bfd_boolean as_needed;
 276
 277   /* Whether to include the entire contents of an archive.  */
 278   bfd_boolean whole_archive;
 279
 280   bfd_boolean loaded;
 281
 282   const char *target;
 283   bfd_boolean real;
 284 } lang_input_statement_type;
 285
 286 typedef struct
 287 {
 288   lang_statement_header_type header;
 289   asection *section;
 290   lang_input_statement_type *ifile;
 291
 292 } lang_input_section_type;
 293
 294 typedef struct
 295 {
 296   lang_statement_header_type header;
 297   asection *section;
 298   union lang_statement_union *file;
 299 } lang_afile_asection_pair_statement_type;
 300
 301 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 302
 303 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 304                             asection *, lang_input_statement_type *, void *);
 305
 306 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 307                                              lang_input_statement_type *,
 308                                              callback_t callback,
 309                                              void *data);
 310
 311 struct lang_wild_statement_struct
 312 {
 313   lang_statement_header_type header;
 314   const char *filename;
 315   bfd_boolean filenames_sorted;
 316   struct wildcard_list *section_list;
 317   bfd_boolean keep_sections;
 318   lang_statement_list_type children;
 319
 320   walk_wild_section_handler_t walk_wild_section_handler;
 321   struct wildcard_list *handler_data[4];
 322 };
 323
 324 typedef struct lang_address_statement_struct
 325 {
 326   lang_statement_header_type header;
 327   const char *section_name;
 328   union etree_union *address;
 329   const segment_type *segment;
 330 } lang_address_statement_type;
 331
 332 typedef struct
 333 {
 334   lang_statement_header_type header;
 335   bfd_vma output_offset;
 336   size_t size;
 337   asection *output_section;
 338   fill_type *fill;
 339 } lang_padding_statement_type;
 340
 341 /* A group statement collects a set of libraries together.  The
 342    libraries are searched multiple times, until no new undefined
 343    symbols are found.  The effect is to search a group of libraries as
 344    though they were a single library.  */
 345
 346 typedef struct
 347 {
 348   lang_statement_header_type header;
 349   lang_statement_list_type children;
 350 } lang_group_statement_type;
 351
 352 typedef union lang_statement_union
 353 {
 354   lang_statement_header_type header;
 355   lang_wild_statement_type wild_statement;
 356   lang_data_statement_type data_statement;
 357   lang_reloc_statement_type reloc_statement;
 358   lang_address_statement_type address_statement;
 359   lang_output_section_statement_type output_section_statement;
 360   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 361   lang_assignment_statement_type assignment_statement;
 362   lang_input_statement_type input_statement;
 363   lang_target_statement_type target_statement;
 364   lang_output_statement_type output_statement;
 365   lang_input_section_type input_section;
 366   lang_common_statement_type common_statement;
 367   lang_object_symbols_statement_type object_symbols_statement;
 368   lang_fill_statement_type fill_statement;
 369   lang_padding_statement_type padding_statement;
 370   lang_group_statement_type group_statement;
 371 } lang_statement_union_type;
 372
 373 /* This structure holds information about a program header, from the
 374    PHDRS command in the linker script.  */
 375
 376 struct lang_phdr
 377 {
 378   struct lang_phdr *next;
 379   const char *name;
 380   unsigned long type;
 381   bfd_boolean filehdr;
 382   bfd_boolean phdrs;
 383   etree_type *at;
 384   etree_type *flags;
 385 };
 386
 387 /* This structure is used to hold a list of sections which may not
 388    cross reference each other.  */
 389
 390 typedef struct lang_nocrossref
 391 {
 392   struct lang_nocrossref *next;
 393   const char *name;
 394 } lang_nocrossref_type;
 395
 396 /* The list of nocrossref lists.  */
 397
 398 struct lang_nocrossrefs
 399 {
 400   struct lang_nocrossrefs *next;
 401   lang_nocrossref_type *list;
 402 };
 403
 404 extern struct lang_nocrossrefs *nocrossref_list;
 405
 406 /* This structure is used to hold a list of input section names which
 407    will not match an output section in the linker script.  */
 408
 409 struct unique_sections
 410 {
 411   struct unique_sections *next;
 412   const char *name;
 413 };
 414
 415 /* This structure records symbols for which we need to keep track of
 416    definedness for use in the DEFINED () test.  */
 417
 418 struct lang_definedness_hash_entry
 419 {
 420   struct bfd_hash_entry root;
 421   int iteration;
 422 };
 423
 424 /* Used by place_orphan to keep track of orphan sections and statements.  */
 425
 426 struct orphan_save {
 427   const char *name;
 428   flagword flags;
 429   lang_output_section_statement_type *os;
 430   asection **section;
 431   lang_statement_union_type **stmt;
 432   lang_output_section_statement_type **os_tail;
 433 };
 434
 435 extern lang_output_section_statement_type *abs_output_section;
 436 extern lang_statement_list_type lang_output_section_statement;
 437 extern bfd_boolean lang_has_input_file;
 438 extern etree_type *base;
 439 extern lang_statement_list_type *stat_ptr;
 440 extern bfd_boolean delete_output_file_on_failure;
 441
 442 extern struct bfd_sym_chain entry_symbol;
 443 extern const char *entry_section;
 444 extern bfd_boolean entry_from_cmdline;
 445 extern lang_statement_list_type file_chain;
 446
 447 extern int lang_statement_iteration;
 448
 449 extern void lang_init
 450   (void);
 451 extern lang_memory_region_type *lang_memory_region_lookup
 452   (const char *const, bfd_boolean);
 453 extern lang_memory_region_type *lang_memory_region_default
 454   (asection *);
 455 extern void lang_map
 456   (void);
 457 extern void lang_set_flags
 458   (lang_memory_region_type *, const char *, int);
 459 extern void lang_add_output
 460   (const char *, int from_script);
 461 extern lang_output_section_statement_type *lang_enter_output_section_statement
 462   (const char *output_section_statement_name,
 463    etree_type *address_exp,
 464    enum section_type sectype,
 465    etree_type *align,
 466    etree_type *subalign,
 467    etree_type *, int);
 468 extern void lang_final
 469   (void);
 470 extern void lang_process
 471   (void);
 472 extern void lang_section_start
 473   (const char *, union etree_union *, const segment_type *);
 474 extern void lang_add_entry
 475   (const char *, bfd_boolean);
 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   (lang_statement_union_type *, lang_output_section_statement_type *,
 510    fill_type *, bfd_vma);
 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 bfd_vma lang_size_sections
 557   (lang_statement_union_type *, lang_output_section_statement_type *,
 558    lang_statement_union_type **, fill_type *, bfd_vma, bfd_boolean *,
 559    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 *);
 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