gdb/progspace.c

   1 /* Program and address space management, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2009-2022 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 #include "defs.h"
  21 #include "gdbcmd.h"
  22 #include "objfiles.h"
  23 #include "arch-utils.h"
  24 #include "gdbcore.h"
  25 #include "solib.h"
  26 #include "solist.h"
  27 #include "gdbthread.h"
  28 #include "inferior.h"
  29 #include <algorithm>
  30 #include "cli/cli-style.h"
  31
  32 /* The last program space number assigned.  */
  33 static int last_program_space_num = 0;
  34
  35 /* The head of the program spaces list.  */
  36 std::vector<struct program_space *> program_spaces;
  37
  38 /* Pointer to the current program space.  */
  39 struct program_space *current_program_space;
  40
  41 /* The last address space number assigned.  */
  42 static int highest_address_space_num;
  43
  44 \f
  45
  46 /* Create a new address space object, and add it to the list.  */
  47
  48 address_space::address_space ()
  49   : m_num (++highest_address_space_num)
  50 {
  51 }
  52
  53 /* Maybe create a new address space object, and add it to the list, or
  54    return a pointer to an existing address space, in case inferiors
  55    share an address space on this target system.  */
  56
  57 struct address_space *
  58 maybe_new_address_space (void)
  59 {
  60   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
  61
  62   if (shared_aspace)
  63     {
  64       /* Just return the first in the list.  */
  65       return program_spaces[0]->aspace;
  66     }
  67
  68   return new address_space ();
  69 }
  70
  71 /* Start counting over from scratch.  */
  72
  73 static void
  74 init_address_spaces (void)
  75 {
  76   highest_address_space_num = 0;
  77 }
  78
  79 \f
  80
  81 /* Remove a program space from the program spaces list.  */
  82
  83 static void
  84 remove_program_space (program_space *pspace)
  85 {
  86   gdb_assert (pspace != NULL);
  87
  88   auto iter = std::find (program_spaces.begin (), program_spaces.end (),
  89                          pspace);
  90   gdb_assert (iter != program_spaces.end ());
  91   program_spaces.erase (iter);
  92 }
  93
  94 /* See progspace.h.  */
  95
  96 program_space::program_space (address_space *aspace_)
  97   : num (++last_program_space_num),
  98     aspace (aspace_)
  99 {
 100   program_spaces.push_back (this);
 101 }
 102
 103 /* See progspace.h.  */
 104
 105 program_space::~program_space ()
 106 {
 107   gdb_assert (this != current_program_space);
 108
 109   remove_program_space (this);
 110
 111   scoped_restore_current_program_space restore_pspace;
 112
 113   set_current_program_space (this);
 114
 115   breakpoint_program_space_exit (this);
 116   no_shared_libraries (NULL, 0);
 117   free_all_objfiles ();
 118   /* Defer breakpoint re-set because we don't want to create new
 119      locations for this pspace which we're tearing down.  */
 120   clear_symtab_users (SYMFILE_DEFER_BP_RESET);
 121   if (!gdbarch_has_shared_address_space (target_gdbarch ()))
 122     delete this->aspace;
 123 }
 124
 125 /* See progspace.h.  */
 126
 127 void
 128 program_space::free_all_objfiles ()
 129 {
 130   /* Any objfile reference would become stale.  */
 131   for (struct so_list *so : current_program_space->solibs ())
 132     gdb_assert (so->objfile == NULL);
 133
 134   while (!objfiles_list.empty ())
 135     objfiles_list.front ()->unlink ();
 136 }
 137
 138 /* See progspace.h.  */
 139
 140 void
 141 program_space::add_objfile (std::unique_ptr<objfile> &&objfile,
 142                             struct objfile *before)
 143 {
 144   if (before == nullptr)
 145     objfiles_list.push_back (std::move (objfile));
 146   else
 147     {
 148       auto iter = std::find_if (objfiles_list.begin (), objfiles_list.end (),
 149                                 [=] (const std::unique_ptr<::objfile> &objf)
 150                                 {
 151                                   return objf.get () == before;
 152                                 });
 153       gdb_assert (iter != objfiles_list.end ());
 154       objfiles_list.insert (iter, std::move (objfile));
 155     }
 156 }
 157
 158 /* See progspace.h.  */
 159
 160 void
 161 program_space::remove_objfile (struct objfile *objfile)
 162 {
 163   /* Removing an objfile from the objfile list invalidates any frame
 164      that was built using frame info found in the objfile.  Reinit the
 165      frame cache to get rid of any frame that might otherwise
 166      reference stale info.  */
 167   reinit_frame_cache ();
 168
 169   auto iter = std::find_if (objfiles_list.begin (), objfiles_list.end (),
 170                             [=] (const std::unique_ptr<::objfile> &objf)
 171                             {
 172                               return objf.get () == objfile;
 173                             });
 174   gdb_assert (iter != objfiles_list.end ());
 175   objfiles_list.erase (iter);
 176
 177   if (objfile == symfile_object_file)
 178     symfile_object_file = NULL;
 179 }
 180
 181 /* See progspace.h.  */
 182
 183 void
 184 program_space::exec_close ()
 185 {
 186   if (ebfd != nullptr)
 187     {
 188       /* Removing target sections may close the exec_ops target.
 189          Clear ebfd before doing so to prevent recursion.  */
 190       ebfd.reset (nullptr);
 191       ebfd_mtime = 0;
 192
 193       remove_target_sections (&ebfd);
 194
 195       exec_filename.reset (nullptr);
 196     }
 197 }
 198
 199 /* Copies program space SRC to DEST.  Copies the main executable file,
 200    and the main symbol file.  Returns DEST.  */
 201
 202 struct program_space *
 203 clone_program_space (struct program_space *dest, struct program_space *src)
 204 {
 205   scoped_restore_current_program_space restore_pspace;
 206
 207   set_current_program_space (dest);
 208
 209   if (src->exec_filename != NULL)
 210     exec_file_attach (src->exec_filename.get (), 0);
 211
 212   if (src->symfile_object_file != NULL)
 213     symbol_file_add_main (objfile_name (src->symfile_object_file),
 214                           SYMFILE_DEFER_BP_RESET);
 215
 216   return dest;
 217 }
 218
 219 /* Sets PSPACE as the current program space.  It is the caller's
 220    responsibility to make sure that the currently selected
 221    inferior/thread matches the selected program space.  */
 222
 223 void
 224 set_current_program_space (struct program_space *pspace)
 225 {
 226   if (current_program_space == pspace)
 227     return;
 228
 229   gdb_assert (pspace != NULL);
 230
 231   current_program_space = pspace;
 232
 233   /* Different symbols change our view of the frame chain.  */
 234   reinit_frame_cache ();
 235 }
 236
 237 /* Returns true iff there's no inferior bound to PSPACE.  */
 238
 239 bool
 240 program_space::empty ()
 241 {
 242   return find_inferior_for_program_space (this) == nullptr;
 243 }
 244
 245 /* Prints the list of program spaces and their details on UIOUT.  If
 246    REQUESTED is not -1, it's the ID of the pspace that should be
 247    printed.  Otherwise, all spaces are printed.  */
 248
 249 static void
 250 print_program_space (struct ui_out *uiout, int requested)
 251 {
 252   int count = 0;
 253
 254   /* Compute number of pspaces we will print.  */
 255   for (struct program_space *pspace : program_spaces)
 256     {
 257       if (requested != -1 && pspace->num != requested)
 258         continue;
 259
 260       ++count;
 261     }
 262
 263   /* There should always be at least one.  */
 264   gdb_assert (count > 0);
 265
 266   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 267   uiout->table_header (1, ui_left, "current", "");
 268   uiout->table_header (4, ui_left, "id", "Id");
 269   uiout->table_header (17, ui_left, "exec", "Executable");
 270   uiout->table_body ();
 271
 272   for (struct program_space *pspace : program_spaces)
 273     {
 274       int printed_header;
 275
 276       if (requested != -1 && requested != pspace->num)
 277         continue;
 278
 279       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 280
 281       if (pspace == current_program_space)
 282         uiout->field_string ("current", "*");
 283       else
 284         uiout->field_skip ("current");
 285
 286       uiout->field_signed ("id", pspace->num);
 287
 288       if (pspace->exec_filename != nullptr)
 289         uiout->field_string ("exec", pspace->exec_filename.get (),
 290                              file_name_style.style ());
 291       else
 292         uiout->field_skip ("exec");
 293
 294       /* Print extra info that doesn't really fit in tabular form.
 295          Currently, we print the list of inferiors bound to a pspace.
 296          There can be more than one inferior bound to the same pspace,
 297          e.g., both parent/child inferiors in a vfork, or, on targets
 298          that share pspaces between inferiors.  */
 299       printed_header = 0;
 300
 301       /* We're going to switch inferiors.  */
 302       scoped_restore_current_thread restore_thread;
 303
 304       for (inferior *inf : all_inferiors ())
 305         if (inf->pspace == pspace)
 306           {
 307             /* Switch to inferior in order to call target methods.  */
 308             switch_to_inferior_no_thread (inf);
 309
 310             if (!printed_header)
 311               {
 312                 printed_header = 1;
 313                 gdb_printf ("\n\tBound inferiors: ID %d (%s)",
 314                             inf->num,
 315                             target_pid_to_str (ptid_t (inf->pid)).c_str ());
 316               }
 317             else
 318               gdb_printf (", ID %d (%s)",
 319                           inf->num,
 320                           target_pid_to_str (ptid_t (inf->pid)).c_str ());
 321           }
 322
 323       uiout->text ("\n");
 324     }
 325 }
 326
 327 /* Boolean test for an already-known program space id.  */
 328
 329 static int
 330 valid_program_space_id (int num)
 331 {
 332   for (struct program_space *pspace : program_spaces)
 333     if (pspace->num == num)
 334       return 1;
 335
 336   return 0;
 337 }
 338
 339 /* If ARGS is NULL or empty, print information about all program
 340    spaces.  Otherwise, ARGS is a text representation of a LONG
 341    indicating which the program space to print information about.  */
 342
 343 static void
 344 maintenance_info_program_spaces_command (const char *args, int from_tty)
 345 {
 346   int requested = -1;
 347
 348   if (args && *args)
 349     {
 350       requested = parse_and_eval_long (args);
 351       if (!valid_program_space_id (requested))
 352         error (_("program space ID %d not known."), requested);
 353     }
 354
 355   print_program_space (current_uiout, requested);
 356 }
 357
 358 /* Update all program spaces matching to address spaces.  The user may
 359    have created several program spaces, and loaded executables into
 360    them before connecting to the target interface that will create the
 361    inferiors.  All that happens before GDB has a chance to know if the
 362    inferiors will share an address space or not.  Call this after
 363    having connected to the target interface and having fetched the
 364    target description, to fixup the program/address spaces mappings.
 365
 366    It is assumed that there are no bound inferiors yet, otherwise,
 367    they'd be left with stale referenced to released aspaces.  */
 368
 369 void
 370 update_address_spaces (void)
 371 {
 372   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 373
 374   init_address_spaces ();
 375
 376   if (shared_aspace)
 377     {
 378       struct address_space *aspace = new address_space ();
 379
 380       delete current_program_space->aspace;
 381       for (struct program_space *pspace : program_spaces)
 382         pspace->aspace = aspace;
 383     }
 384   else
 385     for (struct program_space *pspace : program_spaces)
 386       {
 387         delete pspace->aspace;
 388         pspace->aspace = new address_space ();
 389       }
 390
 391   for (inferior *inf : all_inferiors ())
 392     if (gdbarch_has_global_solist (target_gdbarch ()))
 393       inf->aspace = maybe_new_address_space ();
 394     else
 395       inf->aspace = inf->pspace->aspace;
 396 }
 397
 398 \f
 399
 400 /* See progspace.h.  */
 401
 402 void
 403 program_space::clear_solib_cache ()
 404 {
 405   added_solibs.clear ();
 406   deleted_solibs.clear ();
 407 }
 408
 409 \f
 410
 411 void
 412 initialize_progspace (void)
 413 {
 414   add_cmd ("program-spaces", class_maintenance,
 415            maintenance_info_program_spaces_command,
 416            _("Info about currently known program spaces."),
 417            &maintenanceinfolist);
 418
 419   /* There's always one program space.  Note that this function isn't
 420      an automatic _initialize_foo function, since other
 421      _initialize_foo routines may need to install their per-pspace
 422      data keys.  We can only allocate a progspace when all those
 423      modules have done that.  Do this before
 424      initialize_current_architecture, because that accesses the ebfd
 425      of current_program_space.  */
 426   current_program_space = new program_space (new address_space ());
 427 }