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
   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 section_table;
  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     int sectindex;
  84   } other[1];
  85 };
  86
  87
  88 /* A table listing the load segments in a symfile, and which segment
  89    each BFD section belongs to.  */
  90 struct symfile_segment_data
  91 {
  92   /* How many segments are present in this file.  If there are
  93      two, the text segment is the first one and the data segment
  94      is the second one.  */
  95   int num_segments;
  96
  97   /* If NUM_SEGMENTS is greater than zero, the original base address
  98      of each segment.  */
  99   CORE_ADDR *segment_bases;
 100
 101   /* If NUM_SEGMENTS is greater than zero, the memory size of each
 102      segment.  */
 103   CORE_ADDR *segment_sizes;
 104
 105   /* If NUM_SEGMENTS is greater than zero, this is an array of entries
 106      recording which segment contains each BFD section.
 107      SEGMENT_INFO[I] is S+1 if the I'th BFD section belongs to segment
 108      S, or zero if it is not in any segment.  */
 109   int *segment_info;
 110 };
 111
 112 /* Structure to keep track of symbol reading functions for various
 113    object file types.  */
 114
 115 struct sym_fns
 116 {
 117
 118   /* BFD flavour that we handle, or (as a special kludge, see
 119      xcoffread.c, (enum bfd_flavour)-1 for xcoff).  */
 120
 121   enum bfd_flavour sym_flavour;
 122
 123   /* Initializes anything that is global to the entire symbol table.
 124      It is called during symbol_file_add, when we begin debugging an
 125      entirely new program.  */
 126
 127   void (*sym_new_init) (struct objfile *);
 128
 129   /* Reads any initial information from a symbol file, and initializes
 130      the struct sym_fns SF in preparation for sym_read().  It is
 131      called every time we read a symbol file for any reason.  */
 132
 133   void (*sym_init) (struct objfile *);
 134
 135   /* sym_read (objfile, mainline) Reads a symbol file into a psymtab
 136      (or possibly a symtab).  OBJFILE is the objfile struct for the
 137      file we are reading.  MAINLINE is 1 if this is the main symbol
 138      table being read, and 0 if a secondary symbol file (e.g. shared
 139      library or dynamically loaded file) is being read.  */
 140
 141   void (*sym_read) (struct objfile *, int);
 142
 143   /* Called when we are finished with an objfile.  Should do all
 144      cleanup that is specific to the object file format for the
 145      particular objfile.  */
 146
 147   void (*sym_finish) (struct objfile *);
 148
 149   /* This function produces a file-dependent section_offsets
 150      structure, allocated in the objfile's storage, and based on the
 151      parameter.  The parameter is currently a CORE_ADDR (FIXME!) for
 152      backward compatibility with the higher levels of GDB.  It should
 153      probably be changed to a string, where NULL means the default,
 154      and others are parsed in a file dependent way.  */
 155
 156   void (*sym_offsets) (struct objfile *, struct section_addr_info *);
 157
 158   /* This function produces a format-independent description of
 159      the segments of ABFD.  Each segment is a unit of the file
 160      which may be relocated independently.  */
 161
 162   struct symfile_segment_data *(*sym_segments) (bfd *abfd);
 163
 164   /* This function should read the linetable from the objfile when
 165      the line table cannot be read while processing the debugging
 166      information.  */
 167   void (*sym_read_linetable) (void);
 168
 169   /* Finds the next struct sym_fns.  They are allocated and
 170      initialized in whatever module implements the functions pointed
 171      to; an initializer calls add_symtab_fns to add them to the global
 172      chain.  */
 173
 174   struct sym_fns *next;
 175
 176 };
 177
 178 /* The default version of sym_fns.sym_offsets for readers that don't
 179    do anything special.  */
 180
 181 extern void default_symfile_offsets (struct objfile *objfile,
 182                                      struct section_addr_info *);
 183
 184 /* The default version of sym_fns.sym_segments for readers that don't
 185    do anything special.  */
 186
 187 extern struct symfile_segment_data *default_symfile_segments (bfd *abfd);
 188
 189 extern void extend_psymbol_list (struct psymbol_allocation_list *,
 190                                  struct objfile *);
 191
 192 /* Add any kind of symbol to a psymbol_allocation_list.  */
 193
 194 /* #include "demangle.h" */
 195
 196 extern const
 197 struct partial_symbol *add_psymbol_to_list (char *, int, domain_enum,
 198                                             enum address_class,
 199                                             struct psymbol_allocation_list *,
 200                                             long, CORE_ADDR,
 201                                             enum language, struct objfile *);
 202
 203 extern void init_psymbol_list (struct objfile *, int);
 204
 205 extern void sort_pst_symbols (struct partial_symtab *);
 206
 207 extern struct symtab *allocate_symtab (char *, struct objfile *);
 208
 209 extern int free_named_symtabs (char *);
 210
 211 extern void add_symtab_fns (struct sym_fns *);
 212
 213 extern void syms_from_objfile (struct objfile *,
 214                                struct section_addr_info *,
 215                                struct section_offsets *, int, int, int);
 216
 217 extern void new_symfile_objfile (struct objfile *, int, int);
 218
 219 extern struct objfile *symbol_file_add (char *, int,
 220                                         struct section_addr_info *, int, int);
 221
 222 extern struct objfile *symbol_file_add_from_bfd (bfd *, int,
 223                                                  struct section_addr_info *,
 224                                                  int, int);
 225
 226 /* Create a new section_addr_info, with room for NUM_SECTIONS.  */
 227
 228 extern struct section_addr_info *alloc_section_addr_info (size_t
 229                                                           num_sections);
 230
 231 /* Return a freshly allocated copy of ADDRS.  The section names, if
 232    any, are also freshly allocated copies of those in ADDRS.  */
 233 extern struct section_addr_info *(copy_section_addr_info
 234                                   (struct section_addr_info *addrs));
 235
 236 /* Build (allocate and populate) a section_addr_info struct from an
 237    existing section table.  */
 238
 239 extern struct section_addr_info
 240   *build_section_addr_info_from_section_table (const struct section_table
 241                                                *start,
 242                                                const struct section_table
 243                                                *end);
 244
 245 /* Free all memory allocated by
 246    build_section_addr_info_from_section_table.  */
 247
 248 extern void free_section_addr_info (struct section_addr_info *);
 249
 250
 251 extern struct partial_symtab *start_psymtab_common (struct objfile *,
 252                                                     struct section_offsets *,
 253                                                     char *, CORE_ADDR,
 254                                                     struct partial_symbol **,
 255                                                     struct partial_symbol **);
 256
 257 /* Make a copy of the string at PTR with SIZE characters in the symbol
 258    obstack (and add a null character at the end in the copy).  Returns
 259    the address of the copy.  */
 260
 261 extern char *obsavestring (const char *, int, struct obstack *);
 262
 263 /* Concatenate strings S1, S2 and S3; return the new string.  Space is
 264    found in the OBSTACKP  */
 265
 266 extern char *obconcat (struct obstack *obstackp, const char *, const char *,
 267                        const char *);
 268
 269                         /*   Variables   */
 270
 271 /* If non-zero, gdb will notify the user when it is loading symbols
 272    from a file.  This is almost always what users will want to have happen;
 273    but for programs with lots of dynamically linked libraries, the output
 274    can be more noise than signal.  */
 275
 276 extern int print_symbol_loading;
 277
 278 /* If non-zero, shared library symbols will be added automatically
 279    when the inferior is created, new libraries are loaded, or when
 280    attaching to the inferior.  This is almost always what users will
 281    want to have happen; but for very large programs, the startup time
 282    will be excessive, and so if this is a problem, the user can clear
 283    this flag and then add the shared library symbols as needed.  Note
 284    that there is a potential for confusion, since if the shared
 285    library symbols are not loaded, commands like "info fun" will *not*
 286    report all the functions that are actually present.  */
 287
 288 extern int auto_solib_add;
 289
 290 /* For systems that support it, a threshold size in megabytes.  If
 291    automatically adding a new library's symbol table to those already
 292    known to the debugger would cause the total shared library symbol
 293    size to exceed this threshhold, then the shlib's symbols are not
 294    added.  The threshold is ignored if the user explicitly asks for a
 295    shlib to be added, such as when using the "sharedlibrary" command.  */
 296
 297 extern int auto_solib_limit;
 298
 299 /* From symfile.c */
 300
 301 extern void set_initial_language (void);
 302
 303 extern struct partial_symtab *allocate_psymtab (char *, struct objfile *);
 304
 305 extern void discard_psymtab (struct partial_symtab *);
 306
 307 extern void find_lowest_section (bfd *, asection *, void *);
 308
 309 extern bfd *symfile_bfd_open (char *);
 310
 311 extern int get_section_index (struct objfile *, char *);
 312
 313 /* Utility functions for overlay sections: */
 314 extern enum overlay_debugging_state
 315 {
 316   ovly_off,
 317   ovly_on,
 318   ovly_auto
 319 } overlay_debugging;
 320 extern int overlay_cache_invalid;
 321
 322 /* Return the "mapped" overlay section containing the PC.  */
 323 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 324
 325 /* Return any overlay section containing the PC (even in its LMA
 326    region).  */
 327 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 328
 329 /* Return true if the section is an overlay.  */
 330 extern int section_is_overlay (struct obj_section *);
 331
 332 /* Return true if the overlay section is currently "mapped".  */
 333 extern int section_is_mapped (struct obj_section *);
 334
 335 /* Return true if pc belongs to section's VMA.  */
 336 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 337
 338 /* Return true if pc belongs to section's LMA.  */
 339 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 340
 341 /* Map an address from a section's LMA to its VMA.  */
 342 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 343
 344 /* Map an address from a section's VMA to its LMA.  */
 345 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 346
 347 /* Convert an address in an overlay section (force into VMA range).  */
 348 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 349
 350 /* Load symbols from a file.  */
 351 extern void symbol_file_add_main (char *args, int from_tty);
 352
 353 /* Clear GDB symbol tables.  */
 354 extern void symbol_file_clear (int from_tty);
 355
 356 /* Default overlay update function.  */
 357 extern void simple_overlay_update (struct obj_section *);
 358
 359 extern bfd_byte *symfile_relocate_debug_section (bfd *abfd, asection *sectp,
 360                                                  bfd_byte * buf);
 361
 362 extern int symfile_map_offsets_to_segments (bfd *,
 363                                             struct symfile_segment_data *,
 364                                             struct section_offsets *,
 365                                             int, const CORE_ADDR *);
 366 struct symfile_segment_data *get_symfile_segment_data (bfd *abfd);
 367 void free_symfile_segment_data (struct symfile_segment_data *data);
 368
 369 /* From dwarf2read.c */
 370
 371 extern int dwarf2_has_info (struct objfile *);
 372
 373 extern void dwarf2_build_psymtabs (struct objfile *, int);
 374 extern void dwarf2_build_frame_info (struct objfile *);
 375
 376 void dwarf2_free_objfile (struct objfile *);
 377
 378 /* From mdebugread.c */
 379
 380 /* Hack to force structures to exist before use in parameter list.  */
 381 struct ecoff_debug_hack
 382 {
 383   struct ecoff_debug_swap *a;
 384   struct ecoff_debug_info *b;
 385 };
 386
 387 extern void mdebug_build_psymtabs (struct objfile *,
 388                                    const struct ecoff_debug_swap *,
 389                                    struct ecoff_debug_info *);
 390
 391 extern void elfmdebug_build_psymtabs (struct objfile *,
 392                                       const struct ecoff_debug_swap *,
 393                                       asection *);
 394
 395 #endif /* !defined(SYMFILE_H) */