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   /* Expand each symbol table in OBJFILE that may have items matching
 175      KIND, NAME, and DOMAIN -- these arguments are as for
 176      `lookup_symbol'.  For each such symbol table, call MATCHER with
 177      the symbol table and DATA arguments.  If MATCHER returns NULL,
 178      keep going.  Otherwise, return the result of MATCHER.  If MATCHER
 179      never returns non-NULL, return NULL.  A backend can choose to
 180      implement this and then have its `lookup_symbol' hook always
 181      return NULL, or the reverse.  (It doesn't make sense to implement
 182      both.)  */
 183   struct symbol *(*expand_one_symtab_matching)
 184     (struct objfile *objfile,
 185      int kind, const char *name,
 186      domain_enum domain,
 187      struct symbol *(*matcher) (struct symtab *symtab,
 188                                 int kind,
 189                                 const char *name,
 190                                 domain_enum domain,
 191                                 void *data),
 192      void *data);
 193
 194   /* Print statistics about any indices loaded for OBJFILE.  The
 195      statistics should be printed to gdb_stdout.  This is used for
 196      "maint print statistics".  */
 197   void (*print_stats) (struct objfile *objfile);
 198
 199   /* Dump any indices loaded for OBJFILE.  The dump should go to
 200      gdb_stdout.  This is used for "maint print objfiles".  */
 201   void (*dump) (struct objfile *objfile);
 202
 203   /* This is called by objfile_relocate to relocate any indices loaded
 204      for OBJFILE.  */
 205   void (*relocate) (struct objfile *objfile,
 206                     struct section_offsets *new_offsets,
 207                     struct section_offsets *delta);
 208
 209   /* Find all the symbols in OBJFILE named FUNC_NAME, and ensure that
 210      the corresponding symbol tables are loaded.  */
 211   void (*expand_symtabs_for_function) (struct objfile *objfile,
 212                                        const char *func_name);
 213
 214   /* Read all symbol tables associated with OBJFILE.  */
 215   void (*expand_all_symtabs) (struct objfile *objfile);
 216
 217   /* Read all symbol tables associated with OBJFILE which have the
 218      file name FILENAME.  */
 219   void (*expand_symtabs_with_filename) (struct objfile *objfile,
 220                                         const char *filename);
 221
 222   /* Return the file name of the file holding the symbol in OBJFILE
 223      named NAME.  If no such symbol exists in OBJFILE, return NULL.  */
 224   const char *(*find_symbol_file) (struct objfile *objfile, const char *name);
 225
 226   /* This method is specific to Ada.  It walks the partial symbol
 227      tables of OBJFILE looking for a name match.  WILD_MATCH and
 228      IS_NAME_SUFFIX are predicate functions that the implementation
 229      may call to check for a match.
 230
 231      This function is completely ad hoc and new implementations should
 232      refer to the psymtab implementation to see what to do.  */
 233   void (*map_ada_symtabs) (struct objfile *objfile,
 234                            int (*wild_match) (const char *, int, const char *),
 235                            int (*is_name_suffix) (const char *),
 236                            void (*callback) (struct objfile *,
 237                                              struct symtab *, void *),
 238                            const char *name, int global,
 239                            domain_enum namespace, int wild,
 240                            void *data);
 241
 242   /* Expand all symbol tables in OBJFILE matching some criteria.
 243
 244      FILE_MATCHER is called for each file in OBJFILE.  The file name
 245      and the DATA argument are passed to it.  If it returns zero, this
 246      file is skipped.
 247
 248      Otherwise, if the file is not skipped, then NAME_MATCHER is
 249      called for each symbol defined in the file.  The symbol's
 250      "natural" name and DATA are passed to NAME_MATCHER.
 251
 252      If NAME_MATCHER returns zero, then this symbol is skipped.
 253
 254      Otherwise, if this symbol is not skipped, and it matches KIND,
 255      then this symbol's symbol table is expanded.
 256
 257      DATA is user data that is passed unmodified to the callback
 258      functions.  */
 259   void (*expand_symtabs_matching) (struct objfile *objfile,
 260                                    int (*file_matcher) (const char *, void *),
 261                                    int (*name_matcher) (const char *, void *),
 262                                    domain_enum kind,
 263                                    void *data);
 264
 265   /* Return the symbol table from OBJFILE that contains PC and
 266      SECTION.  Return NULL if there is no such symbol table.  This
 267      should return the symbol table that contains a symbol whose
 268      address exactly matches PC, or, if there is no exact match, the
 269      symbol table that contains a symbol whose address is closest to
 270      PC.  */
 271   struct symtab *(*find_pc_sect_symtab) (struct objfile *objfile,
 272                                          struct minimal_symbol *msymbol,
 273                                          CORE_ADDR pc,
 274                                          struct obj_section *section,
 275                                          int warn_if_readin);
 276
 277   /* Call a callback for every symbol defined in OBJFILE.  FUN is the
 278      callback.  It is passed the symbol's natural name, and the DATA
 279      passed to this function.  */
 280   void (*map_symbol_names) (struct objfile *objfile,
 281                             void (*fun) (const char *, void *),
 282                             void *data);
 283
 284   /* Call a callback for every file defined in OBJFILE.  FUN is the
 285      callback.  It is passed the file's name, the file's full name,
 286      and the DATA passed to this function.  */
 287   void (*map_symbol_filenames) (struct objfile *objfile,
 288                                 void (*fun) (const char *, const char *,
 289                                              void *),
 290                                 void *data);
 291 };
 292
 293 /* Structure to keep track of symbol reading functions for various
 294    object file types.  */
 295
 296 struct sym_fns
 297 {
 298
 299   /* BFD flavour that we handle, or (as a special kludge, see
 300      xcoffread.c, (enum bfd_flavour)-1 for xcoff).  */
 301
 302   enum bfd_flavour sym_flavour;
 303
 304   /* Initializes anything that is global to the entire symbol table.
 305      It is called during symbol_file_add, when we begin debugging an
 306      entirely new program.  */
 307
 308   void (*sym_new_init) (struct objfile *);
 309
 310   /* Reads any initial information from a symbol file, and initializes
 311      the struct sym_fns SF in preparation for sym_read().  It is
 312      called every time we read a symbol file for any reason.  */
 313
 314   void (*sym_init) (struct objfile *);
 315
 316   /* sym_read (objfile, symfile_flags) Reads a symbol file into a psymtab
 317      (or possibly a symtab).  OBJFILE is the objfile struct for the
 318      file we are reading.  SYMFILE_FLAGS are the flags passed to
 319      symbol_file_add & co.  */
 320
 321   void (*sym_read) (struct objfile *, int);
 322
 323   /* Called when we are finished with an objfile.  Should do all
 324      cleanup that is specific to the object file format for the
 325      particular objfile.  */
 326
 327   void (*sym_finish) (struct objfile *);
 328
 329   /* This function produces a file-dependent section_offsets
 330      structure, allocated in the objfile's storage, and based on the
 331      parameter.  The parameter is currently a CORE_ADDR (FIXME!) for
 332      backward compatibility with the higher levels of GDB.  It should
 333      probably be changed to a string, where NULL means the default,
 334      and others are parsed in a file dependent way.  */
 335
 336   void (*sym_offsets) (struct objfile *, struct section_addr_info *);
 337
 338   /* This function produces a format-independent description of
 339      the segments of ABFD.  Each segment is a unit of the file
 340      which may be relocated independently.  */
 341
 342   struct symfile_segment_data *(*sym_segments) (bfd *abfd);
 343
 344   /* This function should read the linetable from the objfile when
 345      the line table cannot be read while processing the debugging
 346      information.  */
 347
 348   void (*sym_read_linetable) (void);
 349
 350   /* Relocate the contents of a debug section SECTP.  The
 351      contents are stored in BUF if it is non-NULL, or returned in a
 352      malloc'd buffer otherwise.  */
 353
 354   bfd_byte *(*sym_relocate) (struct objfile *, asection *sectp, bfd_byte *buf);
 355
 356   /* The "quick" (aka partial) symbol functions for this symbol
 357      reader.  */
 358   const struct quick_symbol_functions *qf;
 359
 360   /* Finds the next struct sym_fns.  They are allocated and
 361      initialized in whatever module implements the functions pointed
 362      to; an initializer calls add_symtab_fns to add them to the global
 363      chain.  */
 364
 365   struct sym_fns *next;
 366
 367 };
 368
 369 extern struct section_addr_info *
 370            build_section_addr_info_from_objfile (const struct objfile *objfile);
 371
 372 extern void relative_addr_info_to_section_offsets
 373   (struct section_offsets *section_offsets, int num_sections,
 374    struct section_addr_info *addrs);
 375
 376 extern void addr_info_make_relative (struct section_addr_info *addrs,
 377                                      bfd *abfd);
 378
 379 /* The default version of sym_fns.sym_offsets for readers that don't
 380    do anything special.  */
 381
 382 extern void default_symfile_offsets (struct objfile *objfile,
 383                                      struct section_addr_info *);
 384
 385 /* The default version of sym_fns.sym_segments for readers that don't
 386    do anything special.  */
 387
 388 extern struct symfile_segment_data *default_symfile_segments (bfd *abfd);
 389
 390 /* The default version of sym_fns.sym_relocate for readers that don't
 391    do anything special.  */
 392
 393 extern bfd_byte *default_symfile_relocate (struct objfile *objfile,
 394                                            asection *sectp, bfd_byte *buf);
 395
 396 extern void extend_psymbol_list (struct psymbol_allocation_list *,
 397                                  struct objfile *);
 398
 399 /* Add any kind of symbol to a psymbol_allocation_list.  */
 400
 401 /* #include "demangle.h" */
 402
 403 extern const
 404 struct partial_symbol *add_psymbol_to_list (char *, int, int, domain_enum,
 405                                             enum address_class,
 406                                             struct psymbol_allocation_list *,
 407                                             long, CORE_ADDR,
 408                                             enum language, struct objfile *);
 409
 410 extern void init_psymbol_list (struct objfile *, int);
 411
 412 extern struct symtab *allocate_symtab (char *, struct objfile *);
 413
 414 extern void add_symtab_fns (struct sym_fns *);
 415
 416 /* This enum encodes bit-flags passed as ADD_FLAGS parameter to
 417    syms_from_objfile, symbol_file_add, etc.  */
 418
 419 enum symfile_add_flags
 420   {
 421     /* Be chatty about what you are doing.  */
 422     SYMFILE_VERBOSE = 1 << 1,
 423
 424     /* This is the main symbol file (as opposed to symbol file for dynamically
 425        loaded code).  */
 426     SYMFILE_MAINLINE = 1 << 2,
 427
 428     /* Do not call breakpoint_re_set when adding this symbol file.  */
 429     SYMFILE_DEFER_BP_RESET = 1 << 3
 430   };
 431
 432 extern void syms_from_objfile (struct objfile *,
 433                                struct section_addr_info *,
 434                                struct section_offsets *, int, int);
 435
 436 extern void new_symfile_objfile (struct objfile *, int);
 437
 438 extern struct objfile *symbol_file_add (char *, int,
 439                                         struct section_addr_info *, int);
 440
 441 extern struct objfile *symbol_file_add_from_bfd (bfd *, int,
 442                                                  struct section_addr_info *,
 443                                                  int);
 444
 445 extern void symbol_file_add_separate (bfd *, int, struct objfile *);
 446
 447 extern char *find_separate_debug_file_by_debuglink (struct objfile *);
 448
 449 /* Create a new section_addr_info, with room for NUM_SECTIONS.  */
 450
 451 extern struct section_addr_info *alloc_section_addr_info (size_t
 452                                                           num_sections);
 453
 454 /* Build (allocate and populate) a section_addr_info struct from an
 455    existing section table.  */
 456
 457 extern struct section_addr_info
 458   *build_section_addr_info_from_section_table (const struct target_section
 459                                                *start,
 460                                                const struct target_section
 461                                                *end);
 462
 463 /* Free all memory allocated by
 464    build_section_addr_info_from_section_table.  */
 465
 466 extern void free_section_addr_info (struct section_addr_info *);
 467
 468
 469 extern struct partial_symtab *start_psymtab_common (struct objfile *,
 470                                                     struct section_offsets *,
 471                                                     const char *, CORE_ADDR,
 472                                                     struct partial_symbol **,
 473                                                     struct partial_symbol **);
 474
 475 /* Make a copy of the string at PTR with SIZE characters in the symbol
 476    obstack (and add a null character at the end in the copy).  Returns
 477    the address of the copy.  */
 478
 479 extern char *obsavestring (const char *, int, struct obstack *);
 480
 481 /* Concatenate NULL terminated variable argument list of `const char *' strings;
 482    return the new string.  Space is found in the OBSTACKP.  Argument list must
 483    be terminated by a sentinel expression `(char *) NULL'.  */
 484
 485 extern char *obconcat (struct obstack *obstackp, ...) ATTRIBUTE_SENTINEL;
 486
 487                         /*   Variables   */
 488
 489 /* If non-zero, shared library symbols will be added automatically
 490    when the inferior is created, new libraries are loaded, or when
 491    attaching to the inferior.  This is almost always what users will
 492    want to have happen; but for very large programs, the startup time
 493    will be excessive, and so if this is a problem, the user can clear
 494    this flag and then add the shared library symbols as needed.  Note
 495    that there is a potential for confusion, since if the shared
 496    library symbols are not loaded, commands like "info fun" will *not*
 497    report all the functions that are actually present.  */
 498
 499 extern int auto_solib_add;
 500
 501 /* For systems that support it, a threshold size in megabytes.  If
 502    automatically adding a new library's symbol table to those already
 503    known to the debugger would cause the total shared library symbol
 504    size to exceed this threshhold, then the shlib's symbols are not
 505    added.  The threshold is ignored if the user explicitly asks for a
 506    shlib to be added, such as when using the "sharedlibrary" command.  */
 507
 508 extern int auto_solib_limit;
 509
 510 /* From symfile.c */
 511
 512 extern void set_initial_language (void);
 513
 514 extern struct partial_symtab *allocate_psymtab (const char *,
 515                                                 struct objfile *);
 516
 517 extern void discard_psymtab (struct partial_symtab *);
 518
 519 extern void find_lowest_section (bfd *, asection *, void *);
 520
 521 extern bfd *symfile_bfd_open (char *);
 522
 523 extern bfd *bfd_open_maybe_remote (const char *);
 524
 525 extern int get_section_index (struct objfile *, char *);
 526
 527 /* Utility functions for overlay sections: */
 528 extern enum overlay_debugging_state
 529 {
 530   ovly_off,
 531   ovly_on,
 532   ovly_auto
 533 } overlay_debugging;
 534 extern int overlay_cache_invalid;
 535
 536 /* Return the "mapped" overlay section containing the PC.  */
 537 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 538
 539 /* Return any overlay section containing the PC (even in its LMA
 540    region).  */
 541 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 542
 543 /* Return true if the section is an overlay.  */
 544 extern int section_is_overlay (struct obj_section *);
 545
 546 /* Return true if the overlay section is currently "mapped".  */
 547 extern int section_is_mapped (struct obj_section *);
 548
 549 /* Return true if pc belongs to section's VMA.  */
 550 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 551
 552 /* Return true if pc belongs to section's LMA.  */
 553 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 554
 555 /* Map an address from a section's LMA to its VMA.  */
 556 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 557
 558 /* Map an address from a section's VMA to its LMA.  */
 559 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 560
 561 /* Convert an address in an overlay section (force into VMA range).  */
 562 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 563
 564 /* Load symbols from a file.  */
 565 extern void symbol_file_add_main (char *args, int from_tty);
 566
 567 /* Clear GDB symbol tables.  */
 568 extern void symbol_file_clear (int from_tty);
 569
 570 /* Default overlay update function.  */
 571 extern void simple_overlay_update (struct obj_section *);
 572
 573 extern bfd_byte *symfile_relocate_debug_section (struct objfile *, asection *,
 574                                                  bfd_byte *);
 575
 576 extern int symfile_map_offsets_to_segments (bfd *,
 577                                             struct symfile_segment_data *,
 578                                             struct section_offsets *,
 579                                             int, const CORE_ADDR *);
 580 struct symfile_segment_data *get_symfile_segment_data (bfd *abfd);
 581 void free_symfile_segment_data (struct symfile_segment_data *data);
 582
 583 extern struct cleanup *increment_reading_symtab (void);
 584
 585 /* From dwarf2read.c */
 586
 587 extern int dwarf2_has_info (struct objfile *);
 588
 589 extern int dwarf2_initialize_objfile (struct objfile *);
 590 extern void dwarf2_build_psymtabs (struct objfile *);
 591 extern void dwarf2_build_frame_info (struct objfile *);
 592
 593 void dwarf2_free_objfile (struct objfile *);
 594
 595 /* From mdebugread.c */
 596
 597 /* Hack to force structures to exist before use in parameter list.  */
 598 struct ecoff_debug_hack
 599 {
 600   struct ecoff_debug_swap *a;
 601   struct ecoff_debug_info *b;
 602 };
 603
 604 extern void mdebug_build_psymtabs (struct objfile *,
 605                                    const struct ecoff_debug_swap *,
 606                                    struct ecoff_debug_info *);
 607
 608 extern void elfmdebug_build_psymtabs (struct objfile *,
 609                                       const struct ecoff_debug_swap *,
 610                                       asection *);
 611
 612 #endif /* !defined(SYMFILE_H) */