gdb/symfile.h

   1 /* Definitions for reading symbol files into GDB.
   2
   3    Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4    2000, 2001, 2002, 2003, 2004, 2007, 2008, 2009, 2010
   5    Free Software Foundation, Inc.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #if !defined (SYMFILE_H)
  23 #define SYMFILE_H
  24
  25 /* This file requires that you first include "bfd.h".  */
  26 #include "symtab.h"
  27
  28 /* Opaque declarations.  */
  29 struct target_section;
  30 struct objfile;
  31 struct obj_section;
  32 struct obstack;
  33 struct block;
  34
  35 /* Partial symbols are stored in the psymbol_cache and pointers to
  36    them are kept in a dynamically grown array that is obtained from
  37    malloc and grown as necessary via realloc.  Each objfile typically
  38    has two of these, one for global symbols and one for static
  39    symbols.  Although this adds a level of indirection for storing or
  40    accessing the partial symbols, it allows us to throw away duplicate
  41    psymbols and set all pointers to the single saved instance.  */
  42
  43 struct psymbol_allocation_list
  44 {
  45
  46   /* Pointer to beginning of dynamically allocated array of pointers
  47      to partial symbols.  The array is dynamically expanded as
  48      necessary to accommodate more pointers.  */
  49
  50   struct partial_symbol **list;
  51
  52   /* Pointer to next available slot in which to store a pointer to a
  53      partial symbol.  */
  54
  55   struct partial_symbol **next;
  56
  57   /* Number of allocated pointer slots in current dynamic array (not
  58      the number of bytes of storage).  The "next" pointer will always
  59      point somewhere between list[0] and list[size], and when at
  60      list[size] the array will be expanded on the next attempt to
  61      store a pointer.  */
  62
  63   int size;
  64 };
  65
  66 /* Define an array of addresses to accommodate non-contiguous dynamic
  67    loading of modules.  This is for use when entering commands, so we
  68    can keep track of the section names until we read the file and can
  69    map them to bfd sections.  This structure is also used by solib.c
  70    to communicate the section addresses in shared objects to
  71    symbol_file_add ().  */
  72
  73 struct section_addr_info
  74 {
  75   /* The number of sections for which address information is
  76      available.  */
  77   size_t num_sections;
  78   /* Sections whose names are file format dependent. */
  79   struct other_sections
  80   {
  81     CORE_ADDR addr;
  82     char *name;
  83
  84     /* SECTINDEX must be valid for associated BFD if ADDR is not zero.  */
  85     int sectindex;
  86   } other[1];
  87 };
  88
  89
  90 /* A table listing the load segments in a symfile, and which segment
  91    each BFD section belongs to.  */
  92 struct symfile_segment_data
  93 {
  94   /* How many segments are present in this file.  If there are
  95      two, the text segment is the first one and the data segment
  96      is the second one.  */
  97   int num_segments;
  98
  99   /* If NUM_SEGMENTS is greater than zero, the original base address
 100      of each segment.  */
 101   CORE_ADDR *segment_bases;
 102
 103   /* If NUM_SEGMENTS is greater than zero, the memory size of each
 104      segment.  */
 105   CORE_ADDR *segment_sizes;
 106
 107   /* If NUM_SEGMENTS is greater than zero, this is an array of entries
 108      recording which segment contains each BFD section.
 109      SEGMENT_INFO[I] is S+1 if the I'th BFD section belongs to segment
 110      S, or zero if it is not in any segment.  */
 111   int *segment_info;
 112 };
 113
 114 /* The "quick" symbol functions exist so that symbol readers can
 115    avoiding an initial read of all the symbols.  For example, symbol
 116    readers might choose to use the "partial symbol table" utilities,
 117    which is one implementation of the quick symbol functions.
 118
 119    The quick symbol functions are generally opaque: the underlying
 120    representation is hidden from the caller.
 121
 122    In general, these functions should only look at whatever special
 123    index the symbol reader creates -- looking through the symbol
 124    tables themselves is handled by generic code.  If a function is
 125    defined as returning a "symbol table", this means that the function
 126    should only return a newly-created symbol table; it should not
 127    examine pre-existing ones.
 128
 129    The exact list of functions here was determined in an ad hoc way
 130    based on gdb's history.  */
 131
 132 struct quick_symbol_functions
 133 {
 134   /* Return true if this objfile has any "partial" symbols
 135      available.  */
 136   int (*has_symbols) (struct objfile *objfile);
 137
 138   /* Return the symbol table for the "last" file appearing in
 139      OBJFILE.  */
 140   struct symtab *(*find_last_source_symtab) (struct objfile *objfile);
 141
 142   /* Forget all cached full file names for OBJFILE.  */
 143   void (*forget_cached_source_info) (struct objfile *objfile);
 144
 145   /* Look up the symbol table, in OBJFILE, of a source file named
 146      NAME.  If there is no '/' in the name, a match after a '/' in the
 147      symbol table's file name will also work.  FULL_PATH is the
 148      absolute file name, and REAL_PATH is the same, run through
 149      gdb_realpath.
 150
 151      If no such symbol table can be found, returns 0.
 152
 153      Otherwise, sets *RESULT to the symbol table and returns 1.  This
 154      might return 1 and set *RESULT to NULL if the requested file is
 155      an include file that does not have a symtab of its own.  */
 156   int (*lookup_symtab) (struct objfile *objfile,
 157                         const char *name,
 158                         const char *full_path,
 159                         const char *real_path,
 160                         struct symtab **result);
 161
 162   /* Check to see if the symbol is defined in a "partial" symbol table
 163      of OBJFILE.  KIND should be either GLOBAL_BLOCK or STATIC_BLOCK,
 164      depending on whether we want to search global symbols or static
 165      symbols.  NAME is the name of the symbol to look for.  DOMAIN
 166      indicates what sort of symbol to search for.
 167
 168      Returns the newly-expanded symbol table in which the symbol is
 169      defined, or NULL if no such symbol table exists.  */
 170   struct symtab *(*lookup_symbol) (struct objfile *objfile,
 171                                    int kind, const char *name,
 172                                    domain_enum domain);
 173
 174   /* This is called to expand symbol tables before looking up a
 175      symbol.  A backend can choose to implement this and then have its
 176      `lookup_symbol' hook always return NULL, or the reverse.  (It
 177      doesn't make sense to implement both.)  The arguments are as for
 178      `lookup_symbol'.  */
 179   void (*pre_expand_symtabs_matching) (struct objfile *objfile,
 180                                        int kind, const char *name,
 181                                        domain_enum domain);
 182
 183   /* Print statistics about any indices loaded for OBJFILE.  The
 184      statistics should be printed to gdb_stdout.  This is used for
 185      "maint print statistics".  */
 186   void (*print_stats) (struct objfile *objfile);
 187
 188   /* Dump any indices loaded for OBJFILE.  The dump should go to
 189      gdb_stdout.  This is used for "maint print objfiles".  */
 190   void (*dump) (struct objfile *objfile);
 191
 192   /* This is called by objfile_relocate to relocate any indices loaded
 193      for OBJFILE.  */
 194   void (*relocate) (struct objfile *objfile,
 195                     struct section_offsets *new_offsets,
 196                     struct section_offsets *delta);
 197
 198   /* Find all the symbols in OBJFILE named FUNC_NAME, and ensure that
 199      the corresponding symbol tables are loaded.  */
 200   void (*expand_symtabs_for_function) (struct objfile *objfile,
 201                                        const char *func_name);
 202
 203   /* Read all symbol tables associated with OBJFILE.  */
 204   void (*expand_all_symtabs) (struct objfile *objfile);
 205
 206   /* Read all symbol tables associated with OBJFILE which have the
 207      file name FILENAME.  */
 208   void (*expand_symtabs_with_filename) (struct objfile *objfile,
 209                                         const char *filename);
 210
 211   /* Return the file name of the file holding the symbol in OBJFILE
 212      named NAME.  If no such symbol exists in OBJFILE, return NULL.  */
 213   char *(*find_symbol_file) (struct objfile *objfile, const char *name);
 214
 215   /* This method is specific to Ada.  It walks the partial symbol
 216      tables of OBJFILE looking for a name match.  WILD_MATCH and
 217      IS_NAME_SUFFIX are predicate functions that the implementation
 218      may call to check for a match.
 219
 220      This function is completely ad hoc and new implementations should
 221      refer to the psymtab implementation to see what to do.  */
 222   void (*map_ada_symtabs) (struct objfile *objfile,
 223                            int (*wild_match) (const char *, int, const char *),
 224                            int (*is_name_suffix) (const char *),
 225                            void (*callback) (struct objfile *,
 226                                              struct symtab *, void *),
 227                            const char *name, int global,
 228                            domain_enum namespace, int wild,
 229                            void *data);
 230
 231   /* Expand all symbol tables in OBJFILE matching some criteria.
 232
 233      FILE_MATCHER is called for each file in OBJFILE.  The file name
 234      and the DATA argument are passed to it.  If it returns zero, this
 235      file is skipped.
 236
 237      Otherwise, if the file is not skipped, then NAME_MATCHER is
 238      called for each symbol defined in the file.  The symbol's
 239      "natural" name and DATA are passed to NAME_MATCHER.
 240
 241      If NAME_MATCHER returns zero, then this symbol is skipped.
 242
 243      Otherwise, if this symbol is not skipped, and it matches KIND,
 244      then this symbol's symbol table is expanded.
 245
 246      DATA is user data that is passed unmodified to the callback
 247      functions.  */
 248   void (*expand_symtabs_matching) (struct objfile *objfile,
 249                                    int (*file_matcher) (const char *, void *),
 250                                    int (*name_matcher) (const char *, void *),
 251                                    domain_enum kind,
 252                                    void *data);
 253
 254   /* Return the symbol table from OBJFILE that contains PC and
 255      SECTION.  Return NULL if there is no such symbol table.  This
 256      should return the symbol table that contains a symbol whose
 257      address exactly matches PC, or, if there is no exact match, the
 258      symbol table that contains a symbol whose address is closest to
 259      PC.  */
 260   struct symtab *(*find_pc_sect_symtab) (struct objfile *objfile,
 261                                          struct minimal_symbol *msymbol,
 262                                          CORE_ADDR pc,
 263                                          struct obj_section *section,
 264                                          int warn_if_readin);
 265
 266   /* Call a callback for every symbol defined in OBJFILE.  FUN is the
 267      callback.  It is passed the symbol's natural name, and the DATA
 268      passed to this function.  */
 269   void (*map_symbol_names) (struct objfile *objfile,
 270                             void (*fun) (const char *, void *),
 271                             void *data);
 272
 273   /* Call a callback for every file defined in OBJFILE.  FUN is the
 274      callback.  It is passed the file's name, the file's full name,
 275      and the DATA passed to this function.  */
 276   void (*map_symbol_filenames) (struct objfile *objfile,
 277                                 void (*fun) (const char *, const char *,
 278                                              void *),
 279                                 void *data);
 280 };
 281
 282 /* Structure to keep track of symbol reading functions for various
 283    object file types.  */
 284
 285 struct sym_fns
 286 {
 287
 288   /* BFD flavour that we handle, or (as a special kludge, see
 289      xcoffread.c, (enum bfd_flavour)-1 for xcoff).  */
 290
 291   enum bfd_flavour sym_flavour;
 292
 293   /* Initializes anything that is global to the entire symbol table.
 294      It is called during symbol_file_add, when we begin debugging an
 295      entirely new program.  */
 296
 297   void (*sym_new_init) (struct objfile *);
 298
 299   /* Reads any initial information from a symbol file, and initializes
 300      the struct sym_fns SF in preparation for sym_read().  It is
 301      called every time we read a symbol file for any reason.  */
 302
 303   void (*sym_init) (struct objfile *);
 304
 305   /* sym_read (objfile, symfile_flags) Reads a symbol file into a psymtab
 306      (or possibly a symtab).  OBJFILE is the objfile struct for the
 307      file we are reading.  SYMFILE_FLAGS are the flags passed to
 308      symbol_file_add & co.  */
 309
 310   void (*sym_read) (struct objfile *, int);
 311
 312   /* Called when we are finished with an objfile.  Should do all
 313      cleanup that is specific to the object file format for the
 314      particular objfile.  */
 315
 316   void (*sym_finish) (struct objfile *);
 317
 318   /* This function produces a file-dependent section_offsets
 319      structure, allocated in the objfile's storage, and based on the
 320      parameter.  The parameter is currently a CORE_ADDR (FIXME!) for
 321      backward compatibility with the higher levels of GDB.  It should
 322      probably be changed to a string, where NULL means the default,
 323      and others are parsed in a file dependent way.  */
 324
 325   void (*sym_offsets) (struct objfile *, struct section_addr_info *);
 326
 327   /* This function produces a format-independent description of
 328      the segments of ABFD.  Each segment is a unit of the file
 329      which may be relocated independently.  */
 330
 331   struct symfile_segment_data *(*sym_segments) (bfd *abfd);
 332
 333   /* This function should read the linetable from the objfile when
 334      the line table cannot be read while processing the debugging
 335      information.  */
 336
 337   void (*sym_read_linetable) (void);
 338
 339   /* Relocate the contents of a debug section SECTP.  The
 340      contents are stored in BUF if it is non-NULL, or returned in a
 341      malloc'd buffer otherwise.  */
 342
 343   bfd_byte *(*sym_relocate) (struct objfile *, asection *sectp, bfd_byte *buf);
 344
 345   /* The "quick" (aka partial) symbol functions for this symbol
 346      reader.  */
 347   const struct quick_symbol_functions *qf;
 348
 349   /* Finds the next struct sym_fns.  They are allocated and
 350      initialized in whatever module implements the functions pointed
 351      to; an initializer calls add_symtab_fns to add them to the global
 352      chain.  */
 353
 354   struct sym_fns *next;
 355
 356 };
 357
 358 extern struct section_addr_info *
 359            build_section_addr_info_from_objfile (const struct objfile *objfile);
 360
 361 extern void relative_addr_info_to_section_offsets
 362   (struct section_offsets *section_offsets, int num_sections,
 363    struct section_addr_info *addrs);
 364
 365 extern void addr_info_make_relative (struct section_addr_info *addrs,
 366                                      bfd *abfd);
 367
 368 /* The default version of sym_fns.sym_offsets for readers that don't
 369    do anything special.  */
 370
 371 extern void default_symfile_offsets (struct objfile *objfile,
 372                                      struct section_addr_info *);
 373
 374 /* The default version of sym_fns.sym_segments for readers that don't
 375    do anything special.  */
 376
 377 extern struct symfile_segment_data *default_symfile_segments (bfd *abfd);
 378
 379 /* The default version of sym_fns.sym_relocate for readers that don't
 380    do anything special.  */
 381
 382 extern bfd_byte *default_symfile_relocate (struct objfile *objfile,
 383                                            asection *sectp, bfd_byte *buf);
 384
 385 extern void extend_psymbol_list (struct psymbol_allocation_list *,
 386                                  struct objfile *);
 387
 388 /* Add any kind of symbol to a psymbol_allocation_list.  */
 389
 390 /* #include "demangle.h" */
 391
 392 extern const
 393 struct partial_symbol *add_psymbol_to_list (char *, int, int, domain_enum,
 394                                             enum address_class,
 395                                             struct psymbol_allocation_list *,
 396                                             long, CORE_ADDR,
 397                                             enum language, struct objfile *);
 398
 399 extern void init_psymbol_list (struct objfile *, int);
 400
 401 extern struct symtab *allocate_symtab (char *, struct objfile *);
 402
 403 extern void add_symtab_fns (struct sym_fns *);
 404
 405 /* This enum encodes bit-flags passed as ADD_FLAGS parameter to
 406    syms_from_objfile, symbol_file_add, etc.  */
 407
 408 enum symfile_add_flags
 409   {
 410     /* Be chatty about what you are doing.  */
 411     SYMFILE_VERBOSE = 1 << 1,
 412
 413     /* This is the main symbol file (as opposed to symbol file for dynamically
 414        loaded code).  */
 415     SYMFILE_MAINLINE = 1 << 2,
 416
 417     /* Do not call breakpoint_re_set when adding this symbol file.  */
 418     SYMFILE_DEFER_BP_RESET = 1 << 3
 419   };
 420
 421 extern void syms_from_objfile (struct objfile *,
 422                                struct section_addr_info *,
 423                                struct section_offsets *, int, int);
 424
 425 extern void new_symfile_objfile (struct objfile *, int);
 426
 427 extern struct objfile *symbol_file_add (char *, int,
 428                                         struct section_addr_info *, int);
 429
 430 extern struct objfile *symbol_file_add_from_bfd (bfd *, int,
 431                                                  struct section_addr_info *,
 432                                                  int);
 433
 434 extern void symbol_file_add_separate (bfd *, int, struct objfile *);
 435
 436 extern char *find_separate_debug_file_by_debuglink (struct objfile *);
 437
 438 /* Create a new section_addr_info, with room for NUM_SECTIONS.  */
 439
 440 extern struct section_addr_info *alloc_section_addr_info (size_t
 441                                                           num_sections);
 442
 443 /* Build (allocate and populate) a section_addr_info struct from an
 444    existing section table.  */
 445
 446 extern struct section_addr_info
 447   *build_section_addr_info_from_section_table (const struct target_section
 448                                                *start,
 449                                                const struct target_section
 450                                                *end);
 451
 452 /* Free all memory allocated by
 453    build_section_addr_info_from_section_table.  */
 454
 455 extern void free_section_addr_info (struct section_addr_info *);
 456
 457
 458 extern struct partial_symtab *start_psymtab_common (struct objfile *,
 459                                                     struct section_offsets *,
 460                                                     const char *, CORE_ADDR,
 461                                                     struct partial_symbol **,
 462                                                     struct partial_symbol **);
 463
 464 /* Make a copy of the string at PTR with SIZE characters in the symbol
 465    obstack (and add a null character at the end in the copy).  Returns
 466    the address of the copy.  */
 467
 468 extern char *obsavestring (const char *, int, struct obstack *);
 469
 470 /* Concatenate NULL terminated variable argument list of `const char *' strings;
 471    return the new string.  Space is found in the OBSTACKP.  Argument list must
 472    be terminated by a sentinel expression `(char *) NULL'.  */
 473
 474 extern char *obconcat (struct obstack *obstackp, ...) ATTRIBUTE_SENTINEL;
 475
 476                         /*   Variables   */
 477
 478 /* If non-zero, shared library symbols will be added automatically
 479    when the inferior is created, new libraries are loaded, or when
 480    attaching to the inferior.  This is almost always what users will
 481    want to have happen; but for very large programs, the startup time
 482    will be excessive, and so if this is a problem, the user can clear
 483    this flag and then add the shared library symbols as needed.  Note
 484    that there is a potential for confusion, since if the shared
 485    library symbols are not loaded, commands like "info fun" will *not*
 486    report all the functions that are actually present.  */
 487
 488 extern int auto_solib_add;
 489
 490 /* For systems that support it, a threshold size in megabytes.  If
 491    automatically adding a new library's symbol table to those already
 492    known to the debugger would cause the total shared library symbol
 493    size to exceed this threshhold, then the shlib's symbols are not
 494    added.  The threshold is ignored if the user explicitly asks for a
 495    shlib to be added, such as when using the "sharedlibrary" command.  */
 496
 497 extern int auto_solib_limit;
 498
 499 /* From symfile.c */
 500
 501 extern void set_initial_language (void);
 502
 503 extern struct partial_symtab *allocate_psymtab (const char *,
 504                                                 struct objfile *);
 505
 506 extern void discard_psymtab (struct partial_symtab *);
 507
 508 extern void find_lowest_section (bfd *, asection *, void *);
 509
 510 extern bfd *symfile_bfd_open (char *);
 511
 512 extern bfd *bfd_open_maybe_remote (const char *);
 513
 514 extern int get_section_index (struct objfile *, char *);
 515
 516 /* Utility functions for overlay sections: */
 517 extern enum overlay_debugging_state
 518 {
 519   ovly_off,
 520   ovly_on,
 521   ovly_auto
 522 } overlay_debugging;
 523 extern int overlay_cache_invalid;
 524
 525 /* Return the "mapped" overlay section containing the PC.  */
 526 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 527
 528 /* Return any overlay section containing the PC (even in its LMA
 529    region).  */
 530 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 531
 532 /* Return true if the section is an overlay.  */
 533 extern int section_is_overlay (struct obj_section *);
 534
 535 /* Return true if the overlay section is currently "mapped".  */
 536 extern int section_is_mapped (struct obj_section *);
 537
 538 /* Return true if pc belongs to section's VMA.  */
 539 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 540
 541 /* Return true if pc belongs to section's LMA.  */
 542 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 543
 544 /* Map an address from a section's LMA to its VMA.  */
 545 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 546
 547 /* Map an address from a section's VMA to its LMA.  */
 548 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 549
 550 /* Convert an address in an overlay section (force into VMA range).  */
 551 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 552
 553 /* Load symbols from a file.  */
 554 extern void symbol_file_add_main (char *args, int from_tty);
 555
 556 /* Clear GDB symbol tables.  */
 557 extern void symbol_file_clear (int from_tty);
 558
 559 /* Default overlay update function.  */
 560 extern void simple_overlay_update (struct obj_section *);
 561
 562 extern bfd_byte *symfile_relocate_debug_section (struct objfile *, asection *,
 563                                                  bfd_byte *);
 564
 565 extern int symfile_map_offsets_to_segments (bfd *,
 566                                             struct symfile_segment_data *,
 567                                             struct section_offsets *,
 568                                             int, const CORE_ADDR *);
 569 struct symfile_segment_data *get_symfile_segment_data (bfd *abfd);
 570 void free_symfile_segment_data (struct symfile_segment_data *data);
 571
 572 extern struct cleanup *increment_reading_symtab (void);
 573
 574 /* From dwarf2read.c */
 575
 576 extern int dwarf2_has_info (struct objfile *);
 577
 578 extern int dwarf2_initialize_objfile (struct objfile *);
 579 extern void dwarf2_build_psymtabs (struct objfile *);
 580 extern void dwarf2_build_frame_info (struct objfile *);
 581
 582 void dwarf2_free_objfile (struct objfile *);
 583
 584 /* From mdebugread.c */
 585
 586 /* Hack to force structures to exist before use in parameter list.  */
 587 struct ecoff_debug_hack
 588 {
 589   struct ecoff_debug_swap *a;
 590   struct ecoff_debug_info *b;
 591 };
 592
 593 extern void mdebug_build_psymtabs (struct objfile *,
 594                                    const struct ecoff_debug_swap *,
 595                                    struct ecoff_debug_info *);
 596
 597 extern void elfmdebug_build_psymtabs (struct objfile *,
 598                                       const struct ecoff_debug_swap *,
 599                                       asection *);
 600
 601 #endif /* !defined(SYMFILE_H) */