gdb/progspace.c

   1 /* Program and address space management, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2009-2019 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 "gdbthread.h"
  27 #include "inferior.h"
  28
  29 /* The last program space number assigned.  */
  30 int last_program_space_num = 0;
  31
  32 /* The head of the program spaces list.  */
  33 struct program_space *program_spaces;
  34
  35 /* Pointer to the current program space.  */
  36 struct program_space *current_program_space;
  37
  38 /* The last address space number assigned.  */
  39 static int highest_address_space_num;
  40
  41 \f
  42
  43 /* Keep a registry of per-program_space data-pointers required by other GDB
  44    modules.  */
  45
  46 DEFINE_REGISTRY (program_space, REGISTRY_ACCESS_FIELD)
  47
  48 /* Keep a registry of per-address_space data-pointers required by other GDB
  49    modules.  */
  50
  51 DEFINE_REGISTRY (address_space, REGISTRY_ACCESS_FIELD)
  52
  53 \f
  54
  55 /* Create a new address space object, and add it to the list.  */
  56
  57 struct address_space *
  58 new_address_space (void)
  59 {
  60   struct address_space *aspace;
  61
  62   aspace = XCNEW (struct address_space);
  63   aspace->num = ++highest_address_space_num;
  64   address_space_alloc_data (aspace);
  65
  66   return aspace;
  67 }
  68
  69 /* Maybe create a new address space object, and add it to the list, or
  70    return a pointer to an existing address space, in case inferiors
  71    share an address space on this target system.  */
  72
  73 struct address_space *
  74 maybe_new_address_space (void)
  75 {
  76   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
  77
  78   if (shared_aspace)
  79     {
  80       /* Just return the first in the list.  */
  81       return program_spaces->aspace;
  82     }
  83
  84   return new_address_space ();
  85 }
  86
  87 static void
  88 free_address_space (struct address_space *aspace)
  89 {
  90   address_space_free_data (aspace);
  91   xfree (aspace);
  92 }
  93
  94 int
  95 address_space_num (struct address_space *aspace)
  96 {
  97   return aspace->num;
  98 }
  99
 100 /* Start counting over from scratch.  */
 101
 102 static void
 103 init_address_spaces (void)
 104 {
 105   highest_address_space_num = 0;
 106 }
 107
 108 \f
 109
 110 /* Adds a new empty program space to the program space list, and binds
 111    it to ASPACE.  Returns the pointer to the new object.  */
 112
 113 program_space::program_space (address_space *aspace_)
 114 : num (++last_program_space_num), aspace (aspace_)
 115 {
 116   program_space_alloc_data (this);
 117
 118   if (program_spaces == NULL)
 119     program_spaces = this;
 120   else
 121     {
 122       struct program_space *last;
 123
 124       for (last = program_spaces; last->next != NULL; last = last->next)
 125         ;
 126       last->next = this;
 127     }
 128 }
 129
 130 /* Releases program space PSPACE, and all its contents (shared
 131    libraries, objfiles, and any other references to the PSPACE in
 132    other modules).  It is an internal error to call this when PSPACE
 133    is the current program space, since there should always be a
 134    program space.  */
 135
 136 program_space::~program_space ()
 137 {
 138   gdb_assert (this != current_program_space);
 139
 140   scoped_restore_current_program_space restore_pspace;
 141
 142   set_current_program_space (this);
 143
 144   breakpoint_program_space_exit (this);
 145   no_shared_libraries (NULL, 0);
 146   exec_close ();
 147   free_all_objfiles ();
 148   if (!gdbarch_has_shared_address_space (target_gdbarch ()))
 149     free_address_space (this->aspace);
 150   clear_section_table (&this->target_sections);
 151   clear_program_space_solib_cache (this);
 152     /* Discard any data modules have associated with the PSPACE.  */
 153   program_space_free_data (this);
 154 }
 155
 156 /* See progspace.h.  */
 157
 158 void
 159 program_space::add_objfile (struct objfile *objfile, struct objfile *before)
 160 {
 161   for (struct objfile **objp = &objfiles_head;
 162        *objp != NULL;
 163        objp = &((*objp)->next))
 164     {
 165       if (*objp == before)
 166         {
 167           objfile->next = *objp;
 168           *objp = objfile;
 169           return;
 170         }
 171     }
 172
 173   internal_error (__FILE__, __LINE__,
 174                   _("put_objfile_before: before objfile not in list"));
 175
 176 }
 177
 178 /* See progspace.h.  */
 179
 180 void
 181 program_space::remove_objfile (struct objfile *objfile)
 182 {
 183   struct objfile **objpp;
 184
 185   for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp)->next))
 186     {
 187       if (*objpp == objfile)
 188         {
 189           *objpp = (*objpp)->next;
 190           objfile->next = NULL;
 191
 192           if (objfile == symfile_object_file)
 193             symfile_object_file = NULL;
 194
 195           return;
 196         }
 197     }
 198
 199   internal_error (__FILE__, __LINE__,
 200                   _("remove_objfile: objfile already unlinked"));
 201 }
 202
 203 /* Copies program space SRC to DEST.  Copies the main executable file,
 204    and the main symbol file.  Returns DEST.  */
 205
 206 struct program_space *
 207 clone_program_space (struct program_space *dest, struct program_space *src)
 208 {
 209   scoped_restore_current_program_space restore_pspace;
 210
 211   set_current_program_space (dest);
 212
 213   if (src->pspace_exec_filename != NULL)
 214     exec_file_attach (src->pspace_exec_filename, 0);
 215
 216   if (src->symfile_object_file != NULL)
 217     symbol_file_add_main (objfile_name (src->symfile_object_file),
 218                           SYMFILE_DEFER_BP_RESET);
 219
 220   return dest;
 221 }
 222
 223 /* Sets PSPACE as the current program space.  It is the caller's
 224    responsibility to make sure that the currently selected
 225    inferior/thread matches the selected program space.  */
 226
 227 void
 228 set_current_program_space (struct program_space *pspace)
 229 {
 230   if (current_program_space == pspace)
 231     return;
 232
 233   gdb_assert (pspace != NULL);
 234
 235   current_program_space = pspace;
 236
 237   /* Different symbols change our view of the frame chain.  */
 238   reinit_frame_cache ();
 239 }
 240
 241 /* Returns true iff there's no inferior bound to PSPACE.  */
 242
 243 int
 244 program_space_empty_p (struct program_space *pspace)
 245 {
 246   if (find_inferior_for_program_space (pspace) != NULL)
 247       return 0;
 248
 249   return 1;
 250 }
 251
 252 /* Remove a program space from the program spaces list and release it.  It is
 253    an error to call this function while PSPACE is the current program space. */
 254
 255 void
 256 delete_program_space (struct program_space *pspace)
 257 {
 258   struct program_space *ss, **ss_link;
 259   gdb_assert (pspace != NULL);
 260   gdb_assert (pspace != current_program_space);
 261
 262   ss = program_spaces;
 263   ss_link = &program_spaces;
 264   while (ss != NULL)
 265     {
 266       if (ss == pspace)
 267         {
 268           *ss_link = ss->next;
 269           break;
 270         }
 271
 272       ss_link = &ss->next;
 273       ss = *ss_link;
 274     }
 275
 276   delete pspace;
 277 }
 278
 279 /* Prints the list of program spaces and their details on UIOUT.  If
 280    REQUESTED is not -1, it's the ID of the pspace that should be
 281    printed.  Otherwise, all spaces are printed.  */
 282
 283 static void
 284 print_program_space (struct ui_out *uiout, int requested)
 285 {
 286   struct program_space *pspace;
 287   int count = 0;
 288
 289   /* Compute number of pspaces we will print.  */
 290   ALL_PSPACES (pspace)
 291     {
 292       if (requested != -1 && pspace->num != requested)
 293         continue;
 294
 295       ++count;
 296     }
 297
 298   /* There should always be at least one.  */
 299   gdb_assert (count > 0);
 300
 301   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 302   uiout->table_header (1, ui_left, "current", "");
 303   uiout->table_header (4, ui_left, "id", "Id");
 304   uiout->table_header (17, ui_left, "exec", "Executable");
 305   uiout->table_body ();
 306
 307   ALL_PSPACES (pspace)
 308     {
 309       struct inferior *inf;
 310       int printed_header;
 311
 312       if (requested != -1 && requested != pspace->num)
 313         continue;
 314
 315       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 316
 317       if (pspace == current_program_space)
 318         uiout->field_string ("current", "*");
 319       else
 320         uiout->field_skip ("current");
 321
 322       uiout->field_signed ("id", pspace->num);
 323
 324       if (pspace->pspace_exec_filename)
 325         uiout->field_string ("exec", pspace->pspace_exec_filename);
 326       else
 327         uiout->field_skip ("exec");
 328
 329       /* Print extra info that doesn't really fit in tabular form.
 330          Currently, we print the list of inferiors bound to a pspace.
 331          There can be more than one inferior bound to the same pspace,
 332          e.g., both parent/child inferiors in a vfork, or, on targets
 333          that share pspaces between inferiors.  */
 334       printed_header = 0;
 335       for (inf = inferior_list; inf; inf = inf->next)
 336         if (inf->pspace == pspace)
 337           {
 338             if (!printed_header)
 339               {
 340                 printed_header = 1;
 341                 printf_filtered ("\n\tBound inferiors: ID %d (%s)",
 342                                  inf->num,
 343                                  target_pid_to_str (ptid_t (inf->pid)).c_str ());
 344               }
 345             else
 346               printf_filtered (", ID %d (%s)",
 347                                inf->num,
 348                                target_pid_to_str (ptid_t (inf->pid)).c_str ());
 349           }
 350
 351       uiout->text ("\n");
 352     }
 353 }
 354
 355 /* Boolean test for an already-known program space id.  */
 356
 357 static int
 358 valid_program_space_id (int num)
 359 {
 360   struct program_space *pspace;
 361
 362   ALL_PSPACES (pspace)
 363     if (pspace->num == num)
 364       return 1;
 365
 366   return 0;
 367 }
 368
 369 /* If ARGS is NULL or empty, print information about all program
 370    spaces.  Otherwise, ARGS is a text representation of a LONG
 371    indicating which the program space to print information about.  */
 372
 373 static void
 374 maintenance_info_program_spaces_command (const char *args, int from_tty)
 375 {
 376   int requested = -1;
 377
 378   if (args && *args)
 379     {
 380       requested = parse_and_eval_long (args);
 381       if (!valid_program_space_id (requested))
 382         error (_("program space ID %d not known."), requested);
 383     }
 384
 385   print_program_space (current_uiout, requested);
 386 }
 387
 388 /* Simply returns the count of program spaces.  */
 389
 390 int
 391 number_of_program_spaces (void)
 392 {
 393   struct program_space *pspace;
 394   int count = 0;
 395
 396   ALL_PSPACES (pspace)
 397     count++;
 398
 399   return count;
 400 }
 401
 402 /* Update all program spaces matching to address spaces.  The user may
 403    have created several program spaces, and loaded executables into
 404    them before connecting to the target interface that will create the
 405    inferiors.  All that happens before GDB has a chance to know if the
 406    inferiors will share an address space or not.  Call this after
 407    having connected to the target interface and having fetched the
 408    target description, to fixup the program/address spaces mappings.
 409
 410    It is assumed that there are no bound inferiors yet, otherwise,
 411    they'd be left with stale referenced to released aspaces.  */
 412
 413 void
 414 update_address_spaces (void)
 415 {
 416   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 417   struct program_space *pspace;
 418   struct inferior *inf;
 419
 420   init_address_spaces ();
 421
 422   if (shared_aspace)
 423     {
 424       struct address_space *aspace = new_address_space ();
 425
 426       free_address_space (current_program_space->aspace);
 427       ALL_PSPACES (pspace)
 428         pspace->aspace = aspace;
 429     }
 430   else
 431     ALL_PSPACES (pspace)
 432       {
 433         free_address_space (pspace->aspace);
 434         pspace->aspace = new_address_space ();
 435       }
 436
 437   for (inf = inferior_list; inf; inf = inf->next)
 438     if (gdbarch_has_global_solist (target_gdbarch ()))
 439       inf->aspace = maybe_new_address_space ();
 440     else
 441       inf->aspace = inf->pspace->aspace;
 442 }
 443
 444 \f
 445
 446 /* See progspace.h.  */
 447
 448 void
 449 clear_program_space_solib_cache (struct program_space *pspace)
 450 {
 451   pspace->added_solibs.clear ();
 452   pspace->deleted_solibs.clear ();
 453 }
 454
 455 \f
 456
 457 void
 458 initialize_progspace (void)
 459 {
 460   add_cmd ("program-spaces", class_maintenance,
 461            maintenance_info_program_spaces_command,
 462            _("Info about currently known program spaces."),
 463            &maintenanceinfolist);
 464
 465   /* There's always one program space.  Note that this function isn't
 466      an automatic _initialize_foo function, since other
 467      _initialize_foo routines may need to install their per-pspace
 468      data keys.  We can only allocate a progspace when all those
 469      modules have done that.  Do this before
 470      initialize_current_architecture, because that accesses exec_bfd,
 471      which in turn dereferences current_program_space.  */
 472   current_program_space = new program_space (new_address_space ());
 473 }