gdb/symfile.h

   1 /* Definitions for reading symbol files into GDB.
   2
   3    Copyright (C) 1990-2021 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #if !defined (SYMFILE_H)
  21 #define SYMFILE_H
  22
  23 /* This file requires that you first include "bfd.h".  */
  24 #include "symtab.h"
  25 #include "probe.h"
  26 #include "symfile-add-flags.h"
  27 #include "objfile-flags.h"
  28 #include "gdb_bfd.h"
  29 #include "gdbsupport/function-view.h"
  30 #include "target-section.h"
  31 #include "quick-symbol.h"
  32
  33 /* Opaque declarations.  */
  34 struct target_section;
  35 struct objfile;
  36 struct obj_section;
  37 struct obstack;
  38 struct block;
  39 struct value;
  40 struct frame_info;
  41 struct agent_expr;
  42 struct axs_value;
  43 class probe;
  44
  45 struct other_sections
  46 {
  47   other_sections (CORE_ADDR addr_, std::string &&name_, int sectindex_)
  48     : addr (addr_),
  49       name (std::move (name_)),
  50       sectindex (sectindex_)
  51   {
  52   }
  53
  54   other_sections (other_sections &&other) = default;
  55
  56   DISABLE_COPY_AND_ASSIGN (other_sections);
  57
  58   CORE_ADDR addr;
  59   std::string name;
  60
  61   /* SECTINDEX must be valid for associated BFD or set to -1.
  62      See syms_from_objfile_1 for an exception to this rule.
  63    */
  64   int sectindex;
  65 };
  66
  67 /* Define an array of addresses to accommodate non-contiguous dynamic
  68    loading of modules.  This is for use when entering commands, so we
  69    can keep track of the section names until we read the file and can
  70    map them to bfd sections.  This structure is also used by solib.c
  71    to communicate the section addresses in shared objects to
  72    symbol_file_add ().  */
  73
  74 typedef std::vector<other_sections> section_addr_info;
  75
  76 /* A table listing the load segments in a symfile, and which segment
  77    each BFD section belongs to.  */
  78 struct symfile_segment_data
  79 {
  80   struct segment
  81   {
  82     segment (CORE_ADDR base, CORE_ADDR size)
  83       : base (base), size (size)
  84     {}
  85
  86     /* The original base address the segment.  */
  87     CORE_ADDR base;
  88
  89     /* The memory size of the segment.  */
  90     CORE_ADDR size;
  91   };
  92
  93   /* The segments present in this file.  If there are
  94      two, the text segment is the first one and the data segment
  95      is the second one.  */
  96   std::vector<segment> segments;
  97
  98   /* This is an array of entries recording which segment contains each BFD
  99      section.  SEGMENT_INFO[I] is S+1 if the I'th BFD section belongs to segment
 100      S, or zero if it is not in any segment.  */
 101   std::vector<int> segment_info;
 102 };
 103
 104 using symfile_segment_data_up = std::unique_ptr<symfile_segment_data>;
 105
 106 /* Structure of functions used for probe support.  If one of these functions
 107    is provided, all must be.  */
 108
 109 struct sym_probe_fns
 110 {
 111   /* If non-NULL, return a reference to vector of probe objects.  */
 112   const std::vector<std::unique_ptr<probe>> &(*sym_get_probes)
 113     (struct objfile *);
 114 };
 115
 116 /* Structure to keep track of symbol reading functions for various
 117    object file types.  */
 118
 119 struct sym_fns
 120 {
 121   /* Initializes anything that is global to the entire symbol table.
 122      It is called during symbol_file_add, when we begin debugging an
 123      entirely new program.  */
 124
 125   void (*sym_new_init) (struct objfile *);
 126
 127   /* Reads any initial information from a symbol file, and initializes
 128      the struct sym_fns SF in preparation for sym_read().  It is
 129      called every time we read a symbol file for any reason.  */
 130
 131   void (*sym_init) (struct objfile *);
 132
 133   /* sym_read (objfile, symfile_flags) Reads a symbol file into a psymtab
 134      (or possibly a symtab).  OBJFILE is the objfile struct for the
 135      file we are reading.  SYMFILE_FLAGS are the flags passed to
 136      symbol_file_add & co.  */
 137
 138   void (*sym_read) (struct objfile *, symfile_add_flags);
 139
 140   /* Called when we are finished with an objfile.  Should do all
 141      cleanup that is specific to the object file format for the
 142      particular objfile.  */
 143
 144   void (*sym_finish) (struct objfile *);
 145
 146
 147   /* This function produces a file-dependent section_offsets
 148      structure, allocated in the objfile's storage.
 149
 150      The section_addr_info structure contains the offset of loadable and
 151      allocated sections, relative to the absolute offsets found in the BFD.  */
 152
 153   void (*sym_offsets) (struct objfile *, const section_addr_info &);
 154
 155   /* This function produces a format-independent description of
 156      the segments of ABFD.  Each segment is a unit of the file
 157      which may be relocated independently.  */
 158
 159   symfile_segment_data_up (*sym_segments) (bfd *abfd);
 160
 161   /* This function should read the linetable from the objfile when
 162      the line table cannot be read while processing the debugging
 163      information.  */
 164
 165   void (*sym_read_linetable) (struct objfile *);
 166
 167   /* Relocate the contents of a debug section SECTP.  The
 168      contents are stored in BUF if it is non-NULL, or returned in a
 169      malloc'd buffer otherwise.  */
 170
 171   bfd_byte *(*sym_relocate) (struct objfile *, asection *sectp, bfd_byte *buf);
 172
 173   /* If non-NULL, this objfile has probe support, and all the probe
 174      functions referred to here will be non-NULL.  */
 175   const struct sym_probe_fns *sym_probe_fns;
 176 };
 177
 178 extern section_addr_info
 179   build_section_addr_info_from_objfile (const struct objfile *objfile);
 180
 181 extern void relative_addr_info_to_section_offsets
 182   (section_offsets &section_offsets, const section_addr_info &addrs);
 183
 184 extern void addr_info_make_relative (section_addr_info *addrs,
 185                                      bfd *abfd);
 186
 187 /* The default version of sym_fns.sym_offsets for readers that don't
 188    do anything special.  */
 189
 190 extern void default_symfile_offsets (struct objfile *objfile,
 191                                      const section_addr_info &);
 192
 193 /* The default version of sym_fns.sym_segments for readers that don't
 194    do anything special.  */
 195
 196 extern symfile_segment_data_up default_symfile_segments (bfd *abfd);
 197
 198 /* The default version of sym_fns.sym_relocate for readers that don't
 199    do anything special.  */
 200
 201 extern bfd_byte *default_symfile_relocate (struct objfile *objfile,
 202                                            asection *sectp, bfd_byte *buf);
 203
 204 extern struct symtab *allocate_symtab (struct compunit_symtab *, const char *)
 205   ATTRIBUTE_NONNULL (1);
 206
 207 extern struct compunit_symtab *allocate_compunit_symtab (struct objfile *,
 208                                                          const char *)
 209   ATTRIBUTE_NONNULL (1);
 210
 211 extern void add_compunit_symtab_to_objfile (struct compunit_symtab *cu);
 212
 213 extern void add_symtab_fns (enum bfd_flavour flavour, const struct sym_fns *);
 214
 215 extern void clear_symtab_users (symfile_add_flags add_flags);
 216
 217 extern enum language deduce_language_from_filename (const char *);
 218
 219 /* Map the filename extension EXT to the language LANG.  Any previous
 220    association of EXT will be removed.  EXT will be copied by this
 221    function.  */
 222 extern void add_filename_language (const char *ext, enum language lang);
 223
 224 extern struct objfile *symbol_file_add (const char *, symfile_add_flags,
 225                                         section_addr_info *, objfile_flags);
 226
 227 extern struct objfile *symbol_file_add_from_bfd (bfd *, const char *, symfile_add_flags,
 228                                                  section_addr_info *,
 229                                                  objfile_flags, struct objfile *parent);
 230
 231 extern void symbol_file_add_separate (bfd *, const char *, symfile_add_flags,
 232                                       struct objfile *);
 233
 234 extern std::string find_separate_debug_file_by_debuglink (struct objfile *);
 235
 236 /* Build (allocate and populate) a section_addr_info struct from an
 237    existing section table.  */
 238
 239 extern section_addr_info
 240     build_section_addr_info_from_section_table (const target_section_table &table);
 241
 242                         /*   Variables   */
 243
 244 /* If true, shared library symbols will be added automatically
 245    when the inferior is created, new libraries are loaded, or when
 246    attaching to the inferior.  This is almost always what users will
 247    want to have happen; but for very large programs, the startup time
 248    will be excessive, and so if this is a problem, the user can clear
 249    this flag and then add the shared library symbols as needed.  Note
 250    that there is a potential for confusion, since if the shared
 251    library symbols are not loaded, commands like "info fun" will *not*
 252    report all the functions that are actually present.  */
 253
 254 extern bool auto_solib_add;
 255
 256 /* From symfile.c */
 257
 258 extern void set_initial_language (void);
 259
 260 extern gdb_bfd_ref_ptr symfile_bfd_open (const char *);
 261
 262 extern int get_section_index (struct objfile *, const char *);
 263
 264 extern int print_symbol_loading_p (int from_tty, int mainline, int full);
 265
 266 /* Utility functions for overlay sections: */
 267 extern enum overlay_debugging_state
 268 {
 269   ovly_off,
 270   ovly_on,
 271   ovly_auto
 272 } overlay_debugging;
 273 extern int overlay_cache_invalid;
 274
 275 /* Return the "mapped" overlay section containing the PC.  */
 276 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 277
 278 /* Return any overlay section containing the PC (even in its LMA
 279    region).  */
 280 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 281
 282 /* Return true if the section is an overlay.  */
 283 extern int section_is_overlay (struct obj_section *);
 284
 285 /* Return true if the overlay section is currently "mapped".  */
 286 extern int section_is_mapped (struct obj_section *);
 287
 288 /* Return true if pc belongs to section's VMA.  */
 289 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 290
 291 /* Return true if pc belongs to section's LMA.  */
 292 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 293
 294 /* Map an address from a section's LMA to its VMA.  */
 295 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 296
 297 /* Map an address from a section's VMA to its LMA.  */
 298 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 299
 300 /* Convert an address in an overlay section (force into VMA range).  */
 301 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 302
 303 /* Load symbols from a file.  */
 304 extern void symbol_file_add_main (const char *args,
 305                                   symfile_add_flags add_flags);
 306
 307 /* Clear GDB symbol tables.  */
 308 extern void symbol_file_clear (int from_tty);
 309
 310 /* Default overlay update function.  */
 311 extern void simple_overlay_update (struct obj_section *);
 312
 313 extern bfd_byte *symfile_relocate_debug_section (struct objfile *, asection *,
 314                                                  bfd_byte *);
 315
 316 extern int symfile_map_offsets_to_segments (bfd *,
 317                                             const struct symfile_segment_data *,
 318                                             section_offsets &,
 319                                             int, const CORE_ADDR *);
 320 symfile_segment_data_up get_symfile_segment_data (bfd *abfd);
 321
 322 extern scoped_restore_tmpl<int> increment_reading_symtab (void);
 323
 324 bool expand_symtabs_matching
 325   (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
 326    const lookup_name_info &lookup_name,
 327    gdb::function_view<expand_symtabs_symbol_matcher_ftype> symbol_matcher,
 328    gdb::function_view<expand_symtabs_exp_notify_ftype> expansion_notify,
 329    block_search_flags search_flags,
 330    enum search_domain kind);
 331
 332 void map_symbol_filenames (gdb::function_view<symbol_filename_ftype> fun,
 333                            bool need_fullname);
 334
 335 /* Target-agnostic function to load the sections of an executable into memory.
 336
 337    ARGS should be in the form "EXECUTABLE [OFFSET]", where OFFSET is an
 338    optional offset to apply to each section.  */
 339 extern void generic_load (const char *args, int from_tty);
 340
 341 /* From minidebug.c.  */
 342
 343 extern gdb_bfd_ref_ptr find_separate_debug_file_in_section (struct objfile *);
 344
 345 /* True if we are printing debug output about separate debug info files.  */
 346
 347 extern bool separate_debug_file_debug;
 348
 349 /* Read full symbols immediately.  */
 350
 351 extern int readnow_symbol_files;
 352
 353 /* Never read full symbols.  */
 354
 355 extern int readnever_symbol_files;
 356
 357 #endif /* !defined(SYMFILE_H) */