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   /* Read the partial symbols for an objfile.  This may be NULL, in which case
 141      gdb has to check other ways if this objfile has any symbols.  This may
 142      only be non-NULL if the objfile actually does have debuginfo available.
 143      */
 144
 145   void (*sym_read_psymbols) (struct objfile *);
 146
 147   /* Called when we are finished with an objfile.  Should do all
 148      cleanup that is specific to the object file format for the
 149      particular objfile.  */
 150
 151   void (*sym_finish) (struct objfile *);
 152
 153
 154   /* This function produces a file-dependent section_offsets
 155      structure, allocated in the objfile's storage.
 156
 157      The section_addr_info structure contains the offset of loadable and
 158      allocated sections, relative to the absolute offsets found in the BFD.  */
 159
 160   void (*sym_offsets) (struct objfile *, const section_addr_info &);
 161
 162   /* This function produces a format-independent description of
 163      the segments of ABFD.  Each segment is a unit of the file
 164      which may be relocated independently.  */
 165
 166   symfile_segment_data_up (*sym_segments) (bfd *abfd);
 167
 168   /* This function should read the linetable from the objfile when
 169      the line table cannot be read while processing the debugging
 170      information.  */
 171
 172   void (*sym_read_linetable) (struct objfile *);
 173
 174   /* Relocate the contents of a debug section SECTP.  The
 175      contents are stored in BUF if it is non-NULL, or returned in a
 176      malloc'd buffer otherwise.  */
 177
 178   bfd_byte *(*sym_relocate) (struct objfile *, asection *sectp, bfd_byte *buf);
 179
 180   /* If non-NULL, this objfile has probe support, and all the probe
 181      functions referred to here will be non-NULL.  */
 182   const struct sym_probe_fns *sym_probe_fns;
 183 };
 184
 185 extern section_addr_info
 186   build_section_addr_info_from_objfile (const struct objfile *objfile);
 187
 188 extern void relative_addr_info_to_section_offsets
 189   (section_offsets &section_offsets, const section_addr_info &addrs);
 190
 191 extern void addr_info_make_relative (section_addr_info *addrs,
 192                                      bfd *abfd);
 193
 194 /* The default version of sym_fns.sym_offsets for readers that don't
 195    do anything special.  */
 196
 197 extern void default_symfile_offsets (struct objfile *objfile,
 198                                      const section_addr_info &);
 199
 200 /* The default version of sym_fns.sym_segments for readers that don't
 201    do anything special.  */
 202
 203 extern symfile_segment_data_up default_symfile_segments (bfd *abfd);
 204
 205 /* The default version of sym_fns.sym_relocate for readers that don't
 206    do anything special.  */
 207
 208 extern bfd_byte *default_symfile_relocate (struct objfile *objfile,
 209                                            asection *sectp, bfd_byte *buf);
 210
 211 extern struct symtab *allocate_symtab (struct compunit_symtab *, const char *)
 212   ATTRIBUTE_NONNULL (1);
 213
 214 extern struct compunit_symtab *allocate_compunit_symtab (struct objfile *,
 215                                                          const char *)
 216   ATTRIBUTE_NONNULL (1);
 217
 218 extern void add_compunit_symtab_to_objfile (struct compunit_symtab *cu);
 219
 220 extern void add_symtab_fns (enum bfd_flavour flavour, const struct sym_fns *);
 221
 222 extern void clear_symtab_users (symfile_add_flags add_flags);
 223
 224 extern enum language deduce_language_from_filename (const char *);
 225
 226 /* Map the filename extension EXT to the language LANG.  Any previous
 227    association of EXT will be removed.  EXT will be copied by this
 228    function.  */
 229 extern void add_filename_language (const char *ext, enum language lang);
 230
 231 extern struct objfile *symbol_file_add (const char *, symfile_add_flags,
 232                                         section_addr_info *, objfile_flags);
 233
 234 extern struct objfile *symbol_file_add_from_bfd (bfd *, const char *, symfile_add_flags,
 235                                                  section_addr_info *,
 236                                                  objfile_flags, struct objfile *parent);
 237
 238 extern void symbol_file_add_separate (bfd *, const char *, symfile_add_flags,
 239                                       struct objfile *);
 240
 241 extern std::string find_separate_debug_file_by_debuglink (struct objfile *);
 242
 243 /* Build (allocate and populate) a section_addr_info struct from an
 244    existing section table.  */
 245
 246 extern section_addr_info
 247     build_section_addr_info_from_section_table (const target_section_table &table);
 248
 249                         /*   Variables   */
 250
 251 /* If true, shared library symbols will be added automatically
 252    when the inferior is created, new libraries are loaded, or when
 253    attaching to the inferior.  This is almost always what users will
 254    want to have happen; but for very large programs, the startup time
 255    will be excessive, and so if this is a problem, the user can clear
 256    this flag and then add the shared library symbols as needed.  Note
 257    that there is a potential for confusion, since if the shared
 258    library symbols are not loaded, commands like "info fun" will *not*
 259    report all the functions that are actually present.  */
 260
 261 extern bool auto_solib_add;
 262
 263 /* From symfile.c */
 264
 265 extern void set_initial_language (void);
 266
 267 extern gdb_bfd_ref_ptr symfile_bfd_open (const char *);
 268
 269 extern int get_section_index (struct objfile *, const char *);
 270
 271 extern int print_symbol_loading_p (int from_tty, int mainline, int full);
 272
 273 /* Utility functions for overlay sections: */
 274 extern enum overlay_debugging_state
 275 {
 276   ovly_off,
 277   ovly_on,
 278   ovly_auto
 279 } overlay_debugging;
 280 extern int overlay_cache_invalid;
 281
 282 /* Return the "mapped" overlay section containing the PC.  */
 283 extern struct obj_section *find_pc_mapped_section (CORE_ADDR);
 284
 285 /* Return any overlay section containing the PC (even in its LMA
 286    region).  */
 287 extern struct obj_section *find_pc_overlay (CORE_ADDR);
 288
 289 /* Return true if the section is an overlay.  */
 290 extern int section_is_overlay (struct obj_section *);
 291
 292 /* Return true if the overlay section is currently "mapped".  */
 293 extern int section_is_mapped (struct obj_section *);
 294
 295 /* Return true if pc belongs to section's VMA.  */
 296 extern CORE_ADDR pc_in_mapped_range (CORE_ADDR, struct obj_section *);
 297
 298 /* Return true if pc belongs to section's LMA.  */
 299 extern CORE_ADDR pc_in_unmapped_range (CORE_ADDR, struct obj_section *);
 300
 301 /* Map an address from a section's LMA to its VMA.  */
 302 extern CORE_ADDR overlay_mapped_address (CORE_ADDR, struct obj_section *);
 303
 304 /* Map an address from a section's VMA to its LMA.  */
 305 extern CORE_ADDR overlay_unmapped_address (CORE_ADDR, struct obj_section *);
 306
 307 /* Convert an address in an overlay section (force into VMA range).  */
 308 extern CORE_ADDR symbol_overlayed_address (CORE_ADDR, struct obj_section *);
 309
 310 /* Load symbols from a file.  */
 311 extern void symbol_file_add_main (const char *args,
 312                                   symfile_add_flags add_flags);
 313
 314 /* Clear GDB symbol tables.  */
 315 extern void symbol_file_clear (int from_tty);
 316
 317 /* Default overlay update function.  */
 318 extern void simple_overlay_update (struct obj_section *);
 319
 320 extern bfd_byte *symfile_relocate_debug_section (struct objfile *, asection *,
 321                                                  bfd_byte *);
 322
 323 extern int symfile_map_offsets_to_segments (bfd *,
 324                                             const struct symfile_segment_data *,
 325                                             section_offsets &,
 326                                             int, const CORE_ADDR *);
 327 symfile_segment_data_up get_symfile_segment_data (bfd *abfd);
 328
 329 extern scoped_restore_tmpl<int> increment_reading_symtab (void);
 330
 331 void expand_symtabs_matching
 332   (gdb::function_view<expand_symtabs_file_matcher_ftype> file_matcher,
 333    const lookup_name_info &lookup_name,
 334    gdb::function_view<expand_symtabs_symbol_matcher_ftype> symbol_matcher,
 335    gdb::function_view<expand_symtabs_exp_notify_ftype> expansion_notify,
 336    enum search_domain kind);
 337
 338 void map_symbol_filenames (symbol_filename_ftype *fun, void *data,
 339                            int need_fullname);
 340
 341 /* Target-agnostic function to load the sections of an executable into memory.
 342
 343    ARGS should be in the form "EXECUTABLE [OFFSET]", where OFFSET is an
 344    optional offset to apply to each section.  */
 345 extern void generic_load (const char *args, int from_tty);
 346
 347 /* From minidebug.c.  */
 348
 349 extern gdb_bfd_ref_ptr find_separate_debug_file_in_section (struct objfile *);
 350
 351 /* True if we are printing debug output about separate debug info files.  */
 352
 353 extern bool separate_debug_file_debug;
 354
 355 /* Read full symbols immediately.  */
 356
 357 extern int readnow_symbol_files;
 358
 359 /* Never read full symbols.  */
 360
 361 extern int readnever_symbol_files;
 362
 363 #endif /* !defined(SYMFILE_H) */