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 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program 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 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #if !defined (SYMFILE_H)
  22 #define SYMFILE_H
  23
  24 /* This file requires that you first include "bfd.h".  */
  25 #include "symtab.h"
  26
  27 /* Opaque declarations.  */
  28 struct section_table;
  29 struct objfile;
  30 struct obj_section;
  31 struct obstack;
  32 struct block;
  33
  34 /* Partial symbols are stored in the psymbol_cache and pointers to
  35    them are kept in a dynamically grown array that is obtained from
  36    malloc and grown as necessary via realloc.  Each objfile typically
  37    has two of these, one for global symbols and one for static
  38    symbols.  Although this adds a level of indirection for storing or
  39    accessing the partial symbols, it allows us to throw away duplicate
  40    psymbols and set all pointers to the single saved instance.  */
  41
  42 struct psymbol_allocation_list
  43 {
  44
  45   /* Pointer to beginning of dynamically allocated array of pointers
  46      to partial symbols.  The array is dynamically expanded as
  47      necessary to accommodate more pointers.  */
  48
  49   struct partial_symbol **list;
  50
  51   /* Pointer to next available slot in which to store a pointer to a
  52      partial symbol.  */
  53
  54   struct partial_symbol **next;
  55
  56   /* Number of allocated pointer slots in current dynamic array (not
  57      the number of bytes of storage).  The "next" pointer will always
  58      point somewhere between list[0] and list[size], and when at
  59      list[size] the array will be expanded on the next attempt to
  60      store a pointer.  */
  61
  62   int size;
  63 };
  64
  65 /* Define an array of addresses to accommodate non-contiguous dynamic
  66    loading of modules.  This is for use when entering commands, so we
  67    can keep track of the section names until we read the file and can
  68    map them to bfd sections.  This structure is also used by solib.c
  69    to communicate the section addresses in shared objects to
  70    symbol_file_add ().  */
  71
  72 struct section_addr_info
  73 {
  74   /* The number of sections for which address information is
  75      available.  */
  76   size_t num_sections;
  77   /* Sections whose names are file format dependent. */
  78   struct other_sections
  79   {
  80     CORE_ADDR addr;
  81     char *name;
  82     int sectindex;
  83   } other[1];
  84 };
  85
  86
  87 /* A table listing the load segments in a symfile, and which segment
  88    each BFD section belongs to.  */
  89 struct symfile_segment_data
  90 {
  91   /* How many segments are present in this file.  If there are
  92      two, the text segment is the first one and the data segment
  93      is the second one.  */
  94   int num_segments;
  95
  96   /* If NUM_SEGMENTS is greater than zero, the original base address
  97      of each segment.  */
  98   CORE_ADDR *segment_bases;
  99
 100   /* If NUM_SEGMENTS is greater than zero, the memory size of each
 101      segment.  */
 102   CORE_ADDR *segment_sizes;
 103
 104   /* If NUM_SEGMENTS is greater than zero, this is an array of entries
 105      recording which segment contains each BFD section.
 106      SEGMENT_INFO[I] is S+1 if the I'th BFD section belongs to segment
 107      S, or zero if it is not in any segment.  */
 108   int *segment_info;
 109 };
 110
 111 /* Structure to keep track of symbol reading functions for various
 112    object file types.  */
 113
 114 struct sym_fns
 115 {
 116
 117   /* BFD flavour that we handle, or (as a special kludge, see
 118      xcoffread.c, (enum bfd_flavour)-1 for xcoff).  */
 119
 120   enum bfd_flavour sym_flavour;
 121
 122   /* Initializes anything that is global to the entire symbol table.
 123      It is called during symbol_file_add, when we begin debugging an
 124      entirely new program.  */
 125
 126   void (*sym_new_init) (struct objfile *);
 127
 128   /* Reads any initial information from a symbol file, and initializes
 129      the struct sym_fns SF in preparation for sym_read().  It is
 130      called every time we read a symbol file for any reason.  */
 131
 132   void (*sym_init) (struct objfile *);
 133
 134   /* sym_read (objfile, mainline) Reads a symbol file into a psymtab
 135      (or possibly a symtab).  OBJFILE is the objfile struct for the
 136      file we are reading.  MAINLINE is 1 if this is the main symbol
 137      table being read, and 0 if a secondary symbol file (e.g. shared
 138      library or dynamically loaded file) is being read.  */
 139
 140   void (*sym_read) (struct objfile *, int);
 141
 142   /* Called when we are finished with an objfile.  Should do all
 143      cleanup that is specific to the object file format for the
 144      particular objfile.  */
 145
 146   void (*sym_finish) (struct objfile *);
 147
 148   /* This function produces a file-dependent section_offsets
 149      structure, allocated in the objfile's storage, and based on the
 150      parameter.  The parameter is currently a CORE_ADDR (FIXME!) for
 151      backward compatibility with the higher levels of GDB.  It should
 152      probably be changed to a string, where NULL means the default,
 153      and others are parsed in a file dependent way.  */
 154
 155   void (*sym_offsets) (struct objfile *, struct section_addr_info *);
 156
 157   /* This function produces a format-independent description of
 158      the segments of ABFD.  Each segment is a unit of the file
 159      which may be relocated independently.  */
 160
 161   struct symfile_segment_data *(*sym_segments) (bfd *abfd);
 162
 163   /* This function should read the linetable from the objfile when
 164      the line table cannot be read while processing the debugging
 165      information.  */
 166   void (*sym_read_linetable) (void);
 167
 168   /* Finds the next struct sym_fns.  They are allocated and
 169      initialized in whatever module implements the functions pointed
 170      to; an initializer calls add_symtab_fns to add them to the global
 171      chain.  */
 172
 173   struct sym_fns *next;
 174
 175 };
 176
 177 /* The default version of sym_fns.sym_offsets for readers that don't
 178    do anything special.  */
 179
 180 extern void default_symfile_offsets (struct objfile *objfile,
 181                                      struct section_addr_info *);
 182
 183 /* The default version of sym_fns.sym_segments for readers that don't
 184    do anything special.  */
 185
 186 extern struct symfile_segment_data *default_symfile_segments (bfd *abfd);
 187
 188 extern void extend_psymbol_list (struct psymbol_allocation_list *,
 189                                  struct objfile *);
 190
 191 /* Add any kind of symbol to a psymbol_allocation_list.  */
 192
 193 /* #include "demangle.h" */
 194
 195 extern const
 196 struct partial_symbol *add_psymbol_to_list (char *, int, domain_enum,
 197                                             enum address_class,
 198                                             struct psymbol_allocation_list *,
 199                                             long, CORE_ADDR,
 200                                             enum language, struct objfile *);
 201
 202 extern void init_psymbol_list (struct objfile *, int);
 203
 204 extern void sort_pst_symbols (struct partial_symtab *);
 205
 206 extern struct symtab *allocate_symtab (char *, struct objfile *);
 207
 208 extern int free_named_symtabs (char *);
 209
 210 extern void add_symtab_fns (struct sym_fns *);
 211
 212 extern void syms_from_objfile (struct objfile *,
 213                                struct section_addr_info *,
 214                                struct section_offsets *, int, int, int);
 215
 216 extern void new_symfile_objfile (struct objfile *, int, int);
 217
 218 extern struct objfile *symbol_file_add (char *, int,
 219                                         struct section_addr_info *, int, int);
 220
 221 extern struct objfile *symbol_file_add_from_bfd (bfd *, int,
 222                                                  struct section_addr_info *,
 223                                                  int, int);
 224
 225 /* Create a new section_addr_info, with room for NUM_SECTIONS.  */
 226
 227 extern struct section_addr_info *alloc_section_addr_info (size_t
 228                                                           num_sections);
 229
 230 /* Return a freshly allocated copy of ADDRS.  The section names, if
 231    any, are also freshly allocated copies of those in ADDRS.  */
 232 extern struct section_addr_info *(copy_section_addr_info
 233                                   (struct section_addr_info *addrs));
 234
 235 /* Build (allocate and populate) a section_addr_info struct from an
 236    existing section table.  */
 237
 238 extern struct section_addr_info
 239   *build_section_addr_info_from_section_table (const struct section_table
 240                                                *start,
 241                                                const struct section_table
 242                                                *end);
 243
 244 /* Free all memory allocated by
 245    build_section_addr_info_from_section_table.  */
 246
 247 extern void free_section_addr_info (struct section_addr_info *);
 248
 249
 250 extern struct partial_symtab *start_psymtab_common (struct objfile *,
 251                                                     struct section_offsets *,
 252                                                     char *, CORE_ADDR,
 253                                                     struct partial_symbol **,
 254                                                     struct partial_symbol **);
 255
 256 /* Make a copy of the string at PTR with SIZE characters in the symbol
 257    obstack (and add a null character at the end in the copy).  Returns
 258    the address of the copy.  */
 259
 260 extern char *obsavestring (const char *, int, struct obstack *);
 261
 262 /* Concatenate strings S1, S2 and S3; return the new string.  Space is
 263    found in the OBSTACKP  */
 264
 265 extern char *obconcat (struct obstack *obstackp, const char *, const char *,
 266                        const char *);
 267
 268                         /*   Variables   */
 269
 270 /* If non-zero, shared library symbols will be added automatically
 271    when the inferior is created, new libraries are loaded, or when
 272    attaching to the inferior.  This is almost always what users will
 273    want to have happen; but for very large programs, the startup time
 274    will be excessive, and so if this is a problem, the user can clear
 275    this flag and then add the shared library symbols as needed.  Note
 276    that there is a potential for confusion, since if the shared
 277    library symbols are not loaded, commands like "info fun" will *not*
 278    report all the functions that are actually present.  */
 279
 280 extern int auto_solib_add;
 281
 282 /* For systems that support it, a threshold size in megabytes.  If
 283    automatically adding a new library's symbol table to those already
 284    known to the debugger would cause the total shared library symbol
 285    size to exceed this threshhold, then the shlib's symbols are not
 286    added.  The threshold is ignored if the user explicitly asks for a
 287    shlib to be added, such as when using the "sharedlibrary" command.  */
 288
 289 extern int auto_solib_limit;
 290
 291 /* From symfile.c */
 292
 293 extern void set_initial_language (void);
 294
 295 extern struct partial_symtab *allocate_psymtab (char *, struct objfile *);
 296
 297 extern void discard_psymtab (struct partial_symtab *);
 298
 299 extern void find_lowest_section (bfd *, asection *, void *);
 300
 301 extern bfd *symfile_bfd_open (char *);
 302
 303 extern int get_section_index (struct objfile *, char *);
 304
 305 /* Utility functions for overlay sections: */
 306 extern enum overlay_debugging_state
 307 {
 308   ovly_off,
 309   ovly_on,
 310   ovly_auto
 311 } overlay_debugging;
 312 extern int overlay_cache_invalid;
 313
 314 /* Return the "mapped" overlay section containing the PC.  */
 315 extern asection *find_pc_mapped_section (CORE_ADDR);
 316
 317 /* Return any overlay section containing the PC (even in its LMA
 318    region).  */
 319 extern asection *find_pc_overlay (CORE_ADDR);
 320
 321 /* Return true if the section is an overlay.  */
 322 extern int section_is_overlay (asection *);
 323
 324 /* Return true if the overlay section is currently "mapped".  */
 325 extern int section_is_mapped (asection *);
 326
 327 /* Return true if pc belongs to section's VMA.  */
 328 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, asection *);
 329
 330 /* Return true if pc belongs to section's LMA.  */
 331 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, asection *);
 332
 333 /* Map an address from a section's LMA to its VMA.  */
 334 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, asection *);
 335
 336 /* Map an address from a section's VMA to its LMA.  */
 337 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, asection *);
 338
 339 /* Convert an address in an overlay section (force into VMA range).  */
 340 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, asection *);
 341
 342 /* Load symbols from a file.  */
 343 extern void symbol_file_add_main (char *args, int from_tty);
 344
 345 /* Clear GDB symbol tables.  */
 346 extern void symbol_file_clear (int from_tty);
 347
 348 /* Default overlay update function.  */
 349 extern void simple_overlay_update (struct obj_section *);
 350
 351 extern bfd_byte *symfile_relocate_debug_section (bfd *abfd, asection *sectp,
 352                                                  bfd_byte * buf);
 353
 354 extern int symfile_map_offsets_to_segments (bfd *,
 355                                             struct symfile_segment_data *,
 356                                             struct section_offsets *,
 357                                             int, const CORE_ADDR *);
 358 struct symfile_segment_data *get_symfile_segment_data (bfd *abfd);
 359 void free_symfile_segment_data (struct symfile_segment_data *data);
 360
 361 /* From dwarf2read.c */
 362
 363 extern int dwarf2_has_info (struct objfile *);
 364
 365 extern void dwarf2_build_psymtabs (struct objfile *, int);
 366 extern void dwarf2_build_frame_info (struct objfile *);
 367
 368 void dwarf2_free_objfile (struct objfile *);
 369
 370 /* From mdebugread.c */
 371
 372 /* Hack to force structures to exist before use in parameter list.  */
 373 struct ecoff_debug_hack
 374 {
 375   struct ecoff_debug_swap *a;
 376   struct ecoff_debug_info *b;
 377 };
 378
 379 extern void mdebug_build_psymtabs (struct objfile *,
 380                                    const struct ecoff_debug_swap *,
 381                                    struct ecoff_debug_info *);
 382
 383 extern void elfmdebug_build_psymtabs (struct objfile *,
 384                                       const struct ecoff_debug_swap *,
 385                                       asection *);
 386
 387 #endif /* !defined(SYMFILE_H) */