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 /* Copies program space SRC to DEST.  Copies the main executable file,
 157    and the main symbol file.  Returns DEST.  */
 158
 159 struct program_space *
 160 clone_program_space (struct program_space *dest, struct program_space *src)
 161 {
 162   scoped_restore_current_program_space restore_pspace;
 163
 164   set_current_program_space (dest);
 165
 166   if (src->pspace_exec_filename != NULL)
 167     exec_file_attach (src->pspace_exec_filename, 0);
 168
 169   if (src->symfile_object_file != NULL)
 170     symbol_file_add_main (objfile_name (src->symfile_object_file),
 171                           SYMFILE_DEFER_BP_RESET);
 172
 173   return dest;
 174 }
 175
 176 /* Sets PSPACE as the current program space.  It is the caller's
 177    responsibility to make sure that the currently selected
 178    inferior/thread matches the selected program space.  */
 179
 180 void
 181 set_current_program_space (struct program_space *pspace)
 182 {
 183   if (current_program_space == pspace)
 184     return;
 185
 186   gdb_assert (pspace != NULL);
 187
 188   current_program_space = pspace;
 189
 190   /* Different symbols change our view of the frame chain.  */
 191   reinit_frame_cache ();
 192 }
 193
 194 /* Returns true iff there's no inferior bound to PSPACE.  */
 195
 196 int
 197 program_space_empty_p (struct program_space *pspace)
 198 {
 199   if (find_inferior_for_program_space (pspace) != NULL)
 200       return 0;
 201
 202   return 1;
 203 }
 204
 205 /* Remove a program space from the program spaces list and release it.  It is
 206    an error to call this function while PSPACE is the current program space. */
 207
 208 void
 209 delete_program_space (struct program_space *pspace)
 210 {
 211   struct program_space *ss, **ss_link;
 212   gdb_assert (pspace != NULL);
 213   gdb_assert (pspace != current_program_space);
 214
 215   ss = program_spaces;
 216   ss_link = &program_spaces;
 217   while (ss != NULL)
 218     {
 219       if (ss == pspace)
 220         {
 221           *ss_link = ss->next;
 222           break;
 223         }
 224
 225       ss_link = &ss->next;
 226       ss = *ss_link;
 227     }
 228
 229   delete pspace;
 230 }
 231
 232 /* Prints the list of program spaces and their details on UIOUT.  If
 233    REQUESTED is not -1, it's the ID of the pspace that should be
 234    printed.  Otherwise, all spaces are printed.  */
 235
 236 static void
 237 print_program_space (struct ui_out *uiout, int requested)
 238 {
 239   struct program_space *pspace;
 240   int count = 0;
 241
 242   /* Compute number of pspaces we will print.  */
 243   ALL_PSPACES (pspace)
 244     {
 245       if (requested != -1 && pspace->num != requested)
 246         continue;
 247
 248       ++count;
 249     }
 250
 251   /* There should always be at least one.  */
 252   gdb_assert (count > 0);
 253
 254   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 255   uiout->table_header (1, ui_left, "current", "");
 256   uiout->table_header (4, ui_left, "id", "Id");
 257   uiout->table_header (17, ui_left, "exec", "Executable");
 258   uiout->table_body ();
 259
 260   ALL_PSPACES (pspace)
 261     {
 262       struct inferior *inf;
 263       int printed_header;
 264
 265       if (requested != -1 && requested != pspace->num)
 266         continue;
 267
 268       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 269
 270       if (pspace == current_program_space)
 271         uiout->field_string ("current", "*");
 272       else
 273         uiout->field_skip ("current");
 274
 275       uiout->field_signed ("id", pspace->num);
 276
 277       if (pspace->pspace_exec_filename)
 278         uiout->field_string ("exec", pspace->pspace_exec_filename);
 279       else
 280         uiout->field_skip ("exec");
 281
 282       /* Print extra info that doesn't really fit in tabular form.
 283          Currently, we print the list of inferiors bound to a pspace.
 284          There can be more than one inferior bound to the same pspace,
 285          e.g., both parent/child inferiors in a vfork, or, on targets
 286          that share pspaces between inferiors.  */
 287       printed_header = 0;
 288       for (inf = inferior_list; inf; inf = inf->next)
 289         if (inf->pspace == pspace)
 290           {
 291             if (!printed_header)
 292               {
 293                 printed_header = 1;
 294                 printf_filtered ("\n\tBound inferiors: ID %d (%s)",
 295                                  inf->num,
 296                                  target_pid_to_str (ptid_t (inf->pid)).c_str ());
 297               }
 298             else
 299               printf_filtered (", ID %d (%s)",
 300                                inf->num,
 301                                target_pid_to_str (ptid_t (inf->pid)).c_str ());
 302           }
 303
 304       uiout->text ("\n");
 305     }
 306 }
 307
 308 /* Boolean test for an already-known program space id.  */
 309
 310 static int
 311 valid_program_space_id (int num)
 312 {
 313   struct program_space *pspace;
 314
 315   ALL_PSPACES (pspace)
 316     if (pspace->num == num)
 317       return 1;
 318
 319   return 0;
 320 }
 321
 322 /* If ARGS is NULL or empty, print information about all program
 323    spaces.  Otherwise, ARGS is a text representation of a LONG
 324    indicating which the program space to print information about.  */
 325
 326 static void
 327 maintenance_info_program_spaces_command (const char *args, int from_tty)
 328 {
 329   int requested = -1;
 330
 331   if (args && *args)
 332     {
 333       requested = parse_and_eval_long (args);
 334       if (!valid_program_space_id (requested))
 335         error (_("program space ID %d not known."), requested);
 336     }
 337
 338   print_program_space (current_uiout, requested);
 339 }
 340
 341 /* Simply returns the count of program spaces.  */
 342
 343 int
 344 number_of_program_spaces (void)
 345 {
 346   struct program_space *pspace;
 347   int count = 0;
 348
 349   ALL_PSPACES (pspace)
 350     count++;
 351
 352   return count;
 353 }
 354
 355 /* Update all program spaces matching to address spaces.  The user may
 356    have created several program spaces, and loaded executables into
 357    them before connecting to the target interface that will create the
 358    inferiors.  All that happens before GDB has a chance to know if the
 359    inferiors will share an address space or not.  Call this after
 360    having connected to the target interface and having fetched the
 361    target description, to fixup the program/address spaces mappings.
 362
 363    It is assumed that there are no bound inferiors yet, otherwise,
 364    they'd be left with stale referenced to released aspaces.  */
 365
 366 void
 367 update_address_spaces (void)
 368 {
 369   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 370   struct program_space *pspace;
 371   struct inferior *inf;
 372
 373   init_address_spaces ();
 374
 375   if (shared_aspace)
 376     {
 377       struct address_space *aspace = new_address_space ();
 378
 379       free_address_space (current_program_space->aspace);
 380       ALL_PSPACES (pspace)
 381         pspace->aspace = aspace;
 382     }
 383   else
 384     ALL_PSPACES (pspace)
 385       {
 386         free_address_space (pspace->aspace);
 387         pspace->aspace = new_address_space ();
 388       }
 389
 390   for (inf = inferior_list; inf; inf = inf->next)
 391     if (gdbarch_has_global_solist (target_gdbarch ()))
 392       inf->aspace = maybe_new_address_space ();
 393     else
 394       inf->aspace = inf->pspace->aspace;
 395 }
 396
 397 \f
 398
 399 /* See progspace.h.  */
 400
 401 void
 402 clear_program_space_solib_cache (struct program_space *pspace)
 403 {
 404   pspace->added_solibs.clear ();
 405   pspace->deleted_solibs.clear ();
 406 }
 407
 408 \f
 409
 410 void
 411 initialize_progspace (void)
 412 {
 413   add_cmd ("program-spaces", class_maintenance,
 414            maintenance_info_program_spaces_command,
 415            _("Info about currently known program spaces."),
 416            &maintenanceinfolist);
 417
 418   /* There's always one program space.  Note that this function isn't
 419      an automatic _initialize_foo function, since other
 420      _initialize_foo routines may need to install their per-pspace
 421      data keys.  We can only allocate a progspace when all those
 422      modules have done that.  Do this before
 423      initialize_current_architecture, because that accesses exec_bfd,
 424      which in turn dereferences current_program_space.  */
 425   current_program_space = new program_space (new_address_space ());
 426 }