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 /* Copies program space SRC to DEST.  Copies the main executable file,
 179    and the main symbol file.  Returns DEST.  */
 180
 181 struct program_space *
 182 clone_program_space (struct program_space *dest, struct program_space *src)
 183 {
 184   scoped_restore_current_program_space restore_pspace;
 185
 186   set_current_program_space (dest);
 187
 188   if (src->pspace_exec_filename != NULL)
 189     exec_file_attach (src->pspace_exec_filename, 0);
 190
 191   if (src->symfile_object_file != NULL)
 192     symbol_file_add_main (objfile_name (src->symfile_object_file),
 193                           SYMFILE_DEFER_BP_RESET);
 194
 195   return dest;
 196 }
 197
 198 /* Sets PSPACE as the current program space.  It is the caller's
 199    responsibility to make sure that the currently selected
 200    inferior/thread matches the selected program space.  */
 201
 202 void
 203 set_current_program_space (struct program_space *pspace)
 204 {
 205   if (current_program_space == pspace)
 206     return;
 207
 208   gdb_assert (pspace != NULL);
 209
 210   current_program_space = pspace;
 211
 212   /* Different symbols change our view of the frame chain.  */
 213   reinit_frame_cache ();
 214 }
 215
 216 /* Returns true iff there's no inferior bound to PSPACE.  */
 217
 218 int
 219 program_space_empty_p (struct program_space *pspace)
 220 {
 221   if (find_inferior_for_program_space (pspace) != NULL)
 222       return 0;
 223
 224   return 1;
 225 }
 226
 227 /* Remove a program space from the program spaces list and release it.  It is
 228    an error to call this function while PSPACE is the current program space. */
 229
 230 void
 231 delete_program_space (struct program_space *pspace)
 232 {
 233   struct program_space *ss, **ss_link;
 234   gdb_assert (pspace != NULL);
 235   gdb_assert (pspace != current_program_space);
 236
 237   ss = program_spaces;
 238   ss_link = &program_spaces;
 239   while (ss != NULL)
 240     {
 241       if (ss == pspace)
 242         {
 243           *ss_link = ss->next;
 244           break;
 245         }
 246
 247       ss_link = &ss->next;
 248       ss = *ss_link;
 249     }
 250
 251   delete pspace;
 252 }
 253
 254 /* Prints the list of program spaces and their details on UIOUT.  If
 255    REQUESTED is not -1, it's the ID of the pspace that should be
 256    printed.  Otherwise, all spaces are printed.  */
 257
 258 static void
 259 print_program_space (struct ui_out *uiout, int requested)
 260 {
 261   struct program_space *pspace;
 262   int count = 0;
 263
 264   /* Compute number of pspaces we will print.  */
 265   ALL_PSPACES (pspace)
 266     {
 267       if (requested != -1 && pspace->num != requested)
 268         continue;
 269
 270       ++count;
 271     }
 272
 273   /* There should always be at least one.  */
 274   gdb_assert (count > 0);
 275
 276   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 277   uiout->table_header (1, ui_left, "current", "");
 278   uiout->table_header (4, ui_left, "id", "Id");
 279   uiout->table_header (17, ui_left, "exec", "Executable");
 280   uiout->table_body ();
 281
 282   ALL_PSPACES (pspace)
 283     {
 284       struct inferior *inf;
 285       int printed_header;
 286
 287       if (requested != -1 && requested != pspace->num)
 288         continue;
 289
 290       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 291
 292       if (pspace == current_program_space)
 293         uiout->field_string ("current", "*");
 294       else
 295         uiout->field_skip ("current");
 296
 297       uiout->field_signed ("id", pspace->num);
 298
 299       if (pspace->pspace_exec_filename)
 300         uiout->field_string ("exec", pspace->pspace_exec_filename);
 301       else
 302         uiout->field_skip ("exec");
 303
 304       /* Print extra info that doesn't really fit in tabular form.
 305          Currently, we print the list of inferiors bound to a pspace.
 306          There can be more than one inferior bound to the same pspace,
 307          e.g., both parent/child inferiors in a vfork, or, on targets
 308          that share pspaces between inferiors.  */
 309       printed_header = 0;
 310       for (inf = inferior_list; inf; inf = inf->next)
 311         if (inf->pspace == pspace)
 312           {
 313             if (!printed_header)
 314               {
 315                 printed_header = 1;
 316                 printf_filtered ("\n\tBound inferiors: ID %d (%s)",
 317                                  inf->num,
 318                                  target_pid_to_str (ptid_t (inf->pid)).c_str ());
 319               }
 320             else
 321               printf_filtered (", ID %d (%s)",
 322                                inf->num,
 323                                target_pid_to_str (ptid_t (inf->pid)).c_str ());
 324           }
 325
 326       uiout->text ("\n");
 327     }
 328 }
 329
 330 /* Boolean test for an already-known program space id.  */
 331
 332 static int
 333 valid_program_space_id (int num)
 334 {
 335   struct program_space *pspace;
 336
 337   ALL_PSPACES (pspace)
 338     if (pspace->num == num)
 339       return 1;
 340
 341   return 0;
 342 }
 343
 344 /* If ARGS is NULL or empty, print information about all program
 345    spaces.  Otherwise, ARGS is a text representation of a LONG
 346    indicating which the program space to print information about.  */
 347
 348 static void
 349 maintenance_info_program_spaces_command (const char *args, int from_tty)
 350 {
 351   int requested = -1;
 352
 353   if (args && *args)
 354     {
 355       requested = parse_and_eval_long (args);
 356       if (!valid_program_space_id (requested))
 357         error (_("program space ID %d not known."), requested);
 358     }
 359
 360   print_program_space (current_uiout, requested);
 361 }
 362
 363 /* Simply returns the count of program spaces.  */
 364
 365 int
 366 number_of_program_spaces (void)
 367 {
 368   struct program_space *pspace;
 369   int count = 0;
 370
 371   ALL_PSPACES (pspace)
 372     count++;
 373
 374   return count;
 375 }
 376
 377 /* Update all program spaces matching to address spaces.  The user may
 378    have created several program spaces, and loaded executables into
 379    them before connecting to the target interface that will create the
 380    inferiors.  All that happens before GDB has a chance to know if the
 381    inferiors will share an address space or not.  Call this after
 382    having connected to the target interface and having fetched the
 383    target description, to fixup the program/address spaces mappings.
 384
 385    It is assumed that there are no bound inferiors yet, otherwise,
 386    they'd be left with stale referenced to released aspaces.  */
 387
 388 void
 389 update_address_spaces (void)
 390 {
 391   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 392   struct program_space *pspace;
 393   struct inferior *inf;
 394
 395   init_address_spaces ();
 396
 397   if (shared_aspace)
 398     {
 399       struct address_space *aspace = new_address_space ();
 400
 401       free_address_space (current_program_space->aspace);
 402       ALL_PSPACES (pspace)
 403         pspace->aspace = aspace;
 404     }
 405   else
 406     ALL_PSPACES (pspace)
 407       {
 408         free_address_space (pspace->aspace);
 409         pspace->aspace = new_address_space ();
 410       }
 411
 412   for (inf = inferior_list; inf; inf = inf->next)
 413     if (gdbarch_has_global_solist (target_gdbarch ()))
 414       inf->aspace = maybe_new_address_space ();
 415     else
 416       inf->aspace = inf->pspace->aspace;
 417 }
 418
 419 \f
 420
 421 /* See progspace.h.  */
 422
 423 void
 424 clear_program_space_solib_cache (struct program_space *pspace)
 425 {
 426   pspace->added_solibs.clear ();
 427   pspace->deleted_solibs.clear ();
 428 }
 429
 430 \f
 431
 432 void
 433 initialize_progspace (void)
 434 {
 435   add_cmd ("program-spaces", class_maintenance,
 436            maintenance_info_program_spaces_command,
 437            _("Info about currently known program spaces."),
 438            &maintenanceinfolist);
 439
 440   /* There's always one program space.  Note that this function isn't
 441      an automatic _initialize_foo function, since other
 442      _initialize_foo routines may need to install their per-pspace
 443      data keys.  We can only allocate a progspace when all those
 444      modules have done that.  Do this before
 445      initialize_current_architecture, because that accesses exec_bfd,
 446      which in turn dereferences current_program_space.  */
 447   current_program_space = new program_space (new_address_space ());
 448 }