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_section_type;
 288
 289 typedef struct
 290 {
 291   lang_statement_header_type header;
 292   asection *section;
 293   union lang_statement_union *file;
 294 } lang_afile_asection_pair_statement_type;
 295
 296 typedef struct lang_wild_statement_struct lang_wild_statement_type;
 297
 298 typedef void (*callback_t) (lang_wild_statement_type *, struct wildcard_list *,
 299                             asection *, lang_input_statement_type *, void *);
 300
 301 typedef void (*walk_wild_section_handler_t) (lang_wild_statement_type *,
 302                                              lang_input_statement_type *,
 303                                              callback_t callback,
 304                                              void *data);
 305
 306 typedef bfd_boolean (*lang_match_sec_type_func) (bfd *, const asection *,
 307                                                  bfd *, const asection *);
 308
 309 struct lang_wild_statement_struct
 310 {
 311   lang_statement_header_type header;
 312   const char *filename;
 313   bfd_boolean filenames_sorted;
 314   struct wildcard_list *section_list;
 315   bfd_boolean keep_sections;
 316   lang_statement_list_type children;
 317
 318   walk_wild_section_handler_t walk_wild_section_handler;
 319   struct wildcard_list *handler_data[4];
 320 };
 321
 322 typedef struct lang_address_statement_struct
 323 {
 324   lang_statement_header_type header;
 325   const char *section_name;
 326   union etree_union *address;
 327   const segment_type *segment;
 328 } lang_address_statement_type;
 329
 330 typedef struct
 331 {
 332   lang_statement_header_type header;
 333   bfd_vma output_offset;
 334   size_t size;
 335   asection *output_section;
 336   fill_type *fill;
 337 } lang_padding_statement_type;
 338
 339 /* A group statement collects a set of libraries together.  The
 340    libraries are searched multiple times, until no new undefined
 341    symbols are found.  The effect is to search a group of libraries as
 342    though they were a single library.  */
 343
 344 typedef struct
 345 {
 346   lang_statement_header_type header;
 347   lang_statement_list_type children;
 348 } lang_group_statement_type;
 349
 350 typedef union lang_statement_union
 351 {
 352   lang_statement_header_type header;
 353   lang_wild_statement_type wild_statement;
 354   lang_data_statement_type data_statement;
 355   lang_reloc_statement_type reloc_statement;
 356   lang_address_statement_type address_statement;
 357   lang_output_section_statement_type output_section_statement;
 358   lang_afile_asection_pair_statement_type afile_asection_pair_statement;
 359   lang_assignment_statement_type assignment_statement;
 360   lang_input_statement_type input_statement;
 361   lang_target_statement_type target_statement;
 362   lang_output_statement_type output_statement;
 363   lang_input_section_type input_section;
 364   lang_common_statement_type common_statement;
 365   lang_object_symbols_statement_type object_symbols_statement;
 366   lang_fill_statement_type fill_statement;
 367   lang_padding_statement_type padding_statement;
 368   lang_group_statement_type group_statement;
 369 } lang_statement_union_type;
 370
 371 /* This structure holds information about a program header, from the
 372    PHDRS command in the linker script.  */
 373
 374 struct lang_phdr
 375 {
 376   struct lang_phdr *next;
 377   const char *name;
 378   unsigned long type;
 379   bfd_boolean filehdr;
 380   bfd_boolean phdrs;
 381   etree_type *at;
 382   etree_type *flags;
 383 };
 384
 385 /* This structure is used to hold a list of sections which may not
 386    cross reference each other.  */
 387
 388 typedef struct lang_nocrossref
 389 {
 390   struct lang_nocrossref *next;
 391   const char *name;
 392 } lang_nocrossref_type;
 393
 394 /* The list of nocrossref lists.  */
 395
 396 struct lang_nocrossrefs
 397 {
 398   struct lang_nocrossrefs *next;
 399   lang_nocrossref_type *list;
 400 };
 401
 402 extern struct lang_nocrossrefs *nocrossref_list;
 403
 404 /* This structure is used to hold a list of input section names which
 405    will not match an output section in the linker script.  */
 406
 407 struct unique_sections
 408 {
 409   struct unique_sections *next;
 410   const char *name;
 411 };
 412
 413 /* This structure records symbols for which we need to keep track of
 414    definedness for use in the DEFINED () test.  */
 415
 416 struct lang_definedness_hash_entry
 417 {
 418   struct bfd_hash_entry root;
 419   int iteration;
 420 };
 421
 422 /* Used by place_orphan to keep track of orphan sections and statements.  */
 423
 424 struct orphan_save {
 425   const char *name;
 426   flagword flags;
 427   lang_output_section_statement_type *os;
 428   asection **section;
 429   lang_statement_union_type **stmt;
 430   lang_output_section_statement_type **os_tail;
 431 };
 432
 433 extern lang_output_section_statement_type *abs_output_section;
 434 extern lang_statement_list_type lang_output_section_statement;
 435 extern bfd_boolean lang_has_input_file;
 436 extern etree_type *base;
 437 extern lang_statement_list_type *stat_ptr;
 438 extern bfd_boolean delete_output_file_on_failure;
 439
 440 extern struct bfd_sym_chain entry_symbol;
 441 extern const char *entry_section;
 442 extern bfd_boolean entry_from_cmdline;
 443 extern lang_statement_list_type file_chain;
 444
 445 extern int lang_statement_iteration;
 446
 447 extern void lang_init
 448   (void);
 449 extern void lang_finish
 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_default_entry
 477   (const char *);
 478 extern void lang_add_target
 479   (const char *);
 480 extern void lang_add_wild
 481   (struct wildcard_spec *, struct wildcard_list *, bfd_boolean);
 482 extern void lang_add_map
 483   (const char *);
 484 extern void lang_add_fill
 485   (fill_type *);
 486 extern lang_assignment_statement_type *lang_add_assignment
 487   (union etree_union *);
 488 extern void lang_add_attribute
 489   (enum statement_enum);
 490 extern void lang_startup
 491   (const char *);
 492 extern void lang_float
 493   (bfd_boolean);
 494 extern void lang_leave_output_section_statement
 495   (fill_type *, const char *, lang_output_section_phdr_list *,
 496    const char *);
 497 extern void lang_abs_symbol_at_end_of
 498   (const char *, const char *);
 499 extern void lang_abs_symbol_at_beginning_of
 500   (const char *, const char *);
 501 extern void lang_statement_append
 502   (lang_statement_list_type *, lang_statement_union_type *,
 503    lang_statement_union_type **);
 504 extern void lang_for_each_input_file
 505   (void (*dothis) (lang_input_statement_type *));
 506 extern void lang_for_each_file
 507   (void (*dothis) (lang_input_statement_type *));
 508 extern void lang_reset_memory_regions
 509   (void);
 510 extern void lang_do_assignments
 511   (void);
 512
 513 #define LANG_FOR_EACH_INPUT_STATEMENT(statement)                        \
 514   lang_input_statement_type *statement;                                 \
 515   for (statement = (lang_input_statement_type *) file_chain.head;       \
 516        statement != (lang_input_statement_type *) NULL;                 \
 517        statement = (lang_input_statement_type *) statement->next)       \
 518
 519 extern void lang_process
 520   (void);
 521 extern void ldlang_add_file
 522   (lang_input_statement_type *);
 523 extern lang_output_section_statement_type *lang_output_section_find
 524   (const char * const);
 525 extern lang_output_section_statement_type *lang_output_section_find_by_flags
 526   (const asection *, lang_output_section_statement_type **,
 527    lang_match_sec_type_func);
 528 extern lang_output_section_statement_type *lang_insert_orphan
 529   (asection *, const char *, lang_output_section_statement_type *,
 530    struct orphan_save *, etree_type *, lang_statement_list_type *);
 531 extern lang_input_statement_type *lang_add_input_file
 532   (const char *, lang_input_file_enum_type, const char *);
 533 extern void lang_add_keepsyms_file
 534   (const char *);
 535 extern lang_output_section_statement_type *
 536   lang_output_section_statement_lookup
 537   (const char *const);
 538 extern void ldlang_add_undef
 539   (const char *const);
 540 extern void lang_add_output_format
 541   (const char *, const char *, const char *, int);
 542 extern void lang_list_init
 543   (lang_statement_list_type *);
 544 extern void lang_add_data
 545   (int type, union etree_union *);
 546 extern void lang_add_reloc
 547   (bfd_reloc_code_real_type, reloc_howto_type *, asection *, const char *,
 548    union etree_union *);
 549 extern void lang_for_each_statement
 550   (void (*) (lang_statement_union_type *));
 551 extern void *stat_alloc
 552   (size_t);
 553 extern void strip_excluded_output_sections
 554   (void);
 555 extern void dprint_statement
 556   (lang_statement_union_type *, int);
 557 extern void lang_size_sections
 558   (bfd_boolean *, bfd_boolean);
 559 extern void one_lang_size_sections_pass
 560   (bfd_boolean *, bfd_boolean);
 561 extern void lang_enter_group
 562   (void);
 563 extern void lang_leave_group
 564   (void);
 565 extern void lang_add_section
 566   (lang_statement_list_type *, asection *,
 567    lang_output_section_statement_type *);
 568 extern void lang_new_phdr
 569   (const char *, etree_type *, bfd_boolean, bfd_boolean, etree_type *,
 570    etree_type *);
 571 extern void lang_add_nocrossref
 572   (lang_nocrossref_type *);
 573 extern void lang_enter_overlay
 574   (etree_type *, etree_type *);
 575 extern void lang_enter_overlay_section
 576   (const char *);
 577 extern void lang_leave_overlay_section
 578   (fill_type *, lang_output_section_phdr_list *);
 579 extern void lang_leave_overlay
 580   (etree_type *, int, fill_type *, const char *,
 581    lang_output_section_phdr_list *, const char *);
 582
 583 extern struct bfd_elf_version_tree *lang_elf_version_info;
 584
 585 extern struct bfd_elf_version_expr *lang_new_vers_pattern
 586   (struct bfd_elf_version_expr *, const char *, const char *, bfd_boolean);
 587 extern struct bfd_elf_version_tree *lang_new_vers_node
 588   (struct bfd_elf_version_expr *, struct bfd_elf_version_expr *);
 589 extern struct bfd_elf_version_deps *lang_add_vers_depend
 590   (struct bfd_elf_version_deps *, const char *);
 591 extern void lang_register_vers_node
 592   (const char *, struct bfd_elf_version_tree *, struct bfd_elf_version_deps *);
 593 bfd_boolean unique_section_p
 594   (const asection *);
 595 extern void lang_add_unique
 596   (const char *);
 597 extern const char *lang_get_output_target
 598   (void);
 599 extern void lang_track_definedness (const char *);
 600 extern int lang_symbol_definition_iteration (const char *);
 601 extern void lang_update_definedness
 602   (const char *, struct bfd_link_hash_entry *);
 603
 604 extern void add_excluded_libs (const char *);
 605
 606 #endif