gdb/progspace.c

   1 /* Program and address space management, for GDB, the GNU debugger.
   2
   3    Copyright (C) 2009-2018 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
  28 /* The last program space number assigned.  */
  29 int last_program_space_num = 0;
  30
  31 /* The head of the program spaces list.  */
  32 struct program_space *program_spaces;
  33
  34 /* Pointer to the current program space.  */
  35 struct program_space *current_program_space;
  36
  37 /* The last address space number assigned.  */
  38 static int highest_address_space_num;
  39
  40 \f
  41
  42 /* Keep a registry of per-program_space data-pointers required by other GDB
  43    modules.  */
  44
  45 DEFINE_REGISTRY (program_space, REGISTRY_ACCESS_FIELD)
  46
  47 /* Keep a registry of per-address_space data-pointers required by other GDB
  48    modules.  */
  49
  50 DEFINE_REGISTRY (address_space, REGISTRY_ACCESS_FIELD)
  51
  52 \f
  53
  54 /* Create a new address space object, and add it to the list.  */
  55
  56 struct address_space *
  57 new_address_space (void)
  58 {
  59   struct address_space *aspace;
  60
  61   aspace = XCNEW (struct address_space);
  62   aspace->num = ++highest_address_space_num;
  63   address_space_alloc_data (aspace);
  64
  65   return aspace;
  66 }
  67
  68 /* Maybe create a new address space object, and add it to the list, or
  69    return a pointer to an existing address space, in case inferiors
  70    share an address space on this target system.  */
  71
  72 struct address_space *
  73 maybe_new_address_space (void)
  74 {
  75   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
  76
  77   if (shared_aspace)
  78     {
  79       /* Just return the first in the list.  */
  80       return program_spaces->aspace;
  81     }
  82
  83   return new_address_space ();
  84 }
  85
  86 static void
  87 free_address_space (struct address_space *aspace)
  88 {
  89   address_space_free_data (aspace);
  90   xfree (aspace);
  91 }
  92
  93 int
  94 address_space_num (struct address_space *aspace)
  95 {
  96   return aspace->num;
  97 }
  98
  99 /* Start counting over from scratch.  */
 100
 101 static void
 102 init_address_spaces (void)
 103 {
 104   highest_address_space_num = 0;
 105 }
 106
 107 \f
 108
 109 /* Adds a new empty program space to the program space list, and binds
 110    it to ASPACE.  Returns the pointer to the new object.  */
 111
 112 struct program_space *
 113 add_program_space (struct address_space *aspace)
 114 {
 115   struct program_space *pspace;
 116
 117   pspace = XCNEW (struct program_space);
 118
 119   pspace->num = ++last_program_space_num;
 120   pspace->aspace = aspace;
 121
 122   program_space_alloc_data (pspace);
 123
 124   if (program_spaces == NULL)
 125     program_spaces = pspace;
 126   else
 127     {
 128       struct program_space *last;
 129
 130       for (last = program_spaces; last->next != NULL; last = last->next)
 131         ;
 132       last->next = pspace;
 133     }
 134
 135   return pspace;
 136 }
 137
 138 /* Releases program space PSPACE, and all its contents (shared
 139    libraries, objfiles, and any other references to the PSPACE in
 140    other modules).  It is an internal error to call this when PSPACE
 141    is the current program space, since there should always be a
 142    program space.  */
 143
 144 static void
 145 release_program_space (struct program_space *pspace)
 146 {
 147   gdb_assert (pspace != current_program_space);
 148
 149   scoped_restore_current_program_space restore_pspace;
 150
 151   set_current_program_space (pspace);
 152
 153   breakpoint_program_space_exit (pspace);
 154   no_shared_libraries (NULL, 0);
 155   exec_close ();
 156   free_all_objfiles ();
 157   if (!gdbarch_has_shared_address_space (target_gdbarch ()))
 158     free_address_space (pspace->aspace);
 159   clear_section_table (&pspace->target_sections);
 160   clear_program_space_solib_cache (pspace);
 161     /* Discard any data modules have associated with the PSPACE.  */
 162   program_space_free_data (pspace);
 163   xfree (pspace);
 164 }
 165
 166 /* Copies program space SRC to DEST.  Copies the main executable file,
 167    and the main symbol file.  Returns DEST.  */
 168
 169 struct program_space *
 170 clone_program_space (struct program_space *dest, struct program_space *src)
 171 {
 172   scoped_restore_current_program_space restore_pspace;
 173
 174   set_current_program_space (dest);
 175
 176   if (src->pspace_exec_filename != NULL)
 177     exec_file_attach (src->pspace_exec_filename, 0);
 178
 179   if (src->symfile_object_file != NULL)
 180     symbol_file_add_main (objfile_name (src->symfile_object_file), 0);
 181
 182   return dest;
 183 }
 184
 185 /* Sets PSPACE as the current program space.  It is the caller's
 186    responsibility to make sure that the currently selected
 187    inferior/thread matches the selected program space.  */
 188
 189 void
 190 set_current_program_space (struct program_space *pspace)
 191 {
 192   if (current_program_space == pspace)
 193     return;
 194
 195   gdb_assert (pspace != NULL);
 196
 197   current_program_space = pspace;
 198
 199   /* Different symbols change our view of the frame chain.  */
 200   reinit_frame_cache ();
 201 }
 202
 203 /* Returns true iff there's no inferior bound to PSPACE.  */
 204
 205 int
 206 program_space_empty_p (struct program_space *pspace)
 207 {
 208   if (find_inferior_for_program_space (pspace) != NULL)
 209       return 0;
 210
 211   return 1;
 212 }
 213
 214 /* Remove a program space from the program spaces list and release it.  It is
 215    an error to call this function while PSPACE is the current program space. */
 216
 217 void
 218 delete_program_space (struct program_space *pspace)
 219 {
 220   struct program_space *ss, **ss_link;
 221   gdb_assert (pspace != NULL);
 222   gdb_assert (pspace != current_program_space);
 223
 224   ss = program_spaces;
 225   ss_link = &program_spaces;
 226   while (ss != NULL)
 227     {
 228       if (ss == pspace)
 229         {
 230           *ss_link = ss->next;
 231           break;
 232         }
 233
 234       ss_link = &ss->next;
 235       ss = *ss_link;
 236     }
 237
 238   release_program_space (pspace);
 239 }
 240
 241 /* Prints the list of program spaces and their details on UIOUT.  If
 242    REQUESTED is not -1, it's the ID of the pspace that should be
 243    printed.  Otherwise, all spaces are printed.  */
 244
 245 static void
 246 print_program_space (struct ui_out *uiout, int requested)
 247 {
 248   struct program_space *pspace;
 249   int count = 0;
 250
 251   /* Compute number of pspaces we will print.  */
 252   ALL_PSPACES (pspace)
 253     {
 254       if (requested != -1 && pspace->num != requested)
 255         continue;
 256
 257       ++count;
 258     }
 259
 260   /* There should always be at least one.  */
 261   gdb_assert (count > 0);
 262
 263   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 264   uiout->table_header (1, ui_left, "current", "");
 265   uiout->table_header (4, ui_left, "id", "Id");
 266   uiout->table_header (17, ui_left, "exec", "Executable");
 267   uiout->table_body ();
 268
 269   ALL_PSPACES (pspace)
 270     {
 271       struct inferior *inf;
 272       int printed_header;
 273
 274       if (requested != -1 && requested != pspace->num)
 275         continue;
 276
 277       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 278
 279       if (pspace == current_program_space)
 280         uiout->field_string ("current", "*");
 281       else
 282         uiout->field_skip ("current");
 283
 284       uiout->field_int ("id", pspace->num);
 285
 286       if (pspace->pspace_exec_filename)
 287         uiout->field_string ("exec", pspace->pspace_exec_filename);
 288       else
 289         uiout->field_skip ("exec");
 290
 291       /* Print extra info that doesn't really fit in tabular form.
 292          Currently, we print the list of inferiors bound to a pspace.
 293          There can be more than one inferior bound to the same pspace,
 294          e.g., both parent/child inferiors in a vfork, or, on targets
 295          that share pspaces between inferiors.  */
 296       printed_header = 0;
 297       for (inf = inferior_list; inf; inf = inf->next)
 298         if (inf->pspace == pspace)
 299           {
 300             if (!printed_header)
 301               {
 302                 printed_header = 1;
 303                 printf_filtered ("\n\tBound inferiors: ID %d (%s)",
 304                                  inf->num,
 305                                  target_pid_to_str (pid_to_ptid (inf->pid)));
 306               }
 307             else
 308               printf_filtered (", ID %d (%s)",
 309                                inf->num,
 310                                target_pid_to_str (pid_to_ptid (inf->pid)));
 311           }
 312
 313       uiout->text ("\n");
 314     }
 315 }
 316
 317 /* Boolean test for an already-known program space id.  */
 318
 319 static int
 320 valid_program_space_id (int num)
 321 {
 322   struct program_space *pspace;
 323
 324   ALL_PSPACES (pspace)
 325     if (pspace->num == num)
 326       return 1;
 327
 328   return 0;
 329 }
 330
 331 /* If ARGS is NULL or empty, print information about all program
 332    spaces.  Otherwise, ARGS is a text representation of a LONG
 333    indicating which the program space to print information about.  */
 334
 335 static void
 336 maintenance_info_program_spaces_command (const char *args, int from_tty)
 337 {
 338   int requested = -1;
 339
 340   if (args && *args)
 341     {
 342       requested = parse_and_eval_long (args);
 343       if (!valid_program_space_id (requested))
 344         error (_("program space ID %d not known."), requested);
 345     }
 346
 347   print_program_space (current_uiout, requested);
 348 }
 349
 350 /* Simply returns the count of program spaces.  */
 351
 352 int
 353 number_of_program_spaces (void)
 354 {
 355   struct program_space *pspace;
 356   int count = 0;
 357
 358   ALL_PSPACES (pspace)
 359     count++;
 360
 361   return count;
 362 }
 363
 364 /* Update all program spaces matching to address spaces.  The user may
 365    have created several program spaces, and loaded executables into
 366    them before connecting to the target interface that will create the
 367    inferiors.  All that happens before GDB has a chance to know if the
 368    inferiors will share an address space or not.  Call this after
 369    having connected to the target interface and having fetched the
 370    target description, to fixup the program/address spaces mappings.
 371
 372    It is assumed that there are no bound inferiors yet, otherwise,
 373    they'd be left with stale referenced to released aspaces.  */
 374
 375 void
 376 update_address_spaces (void)
 377 {
 378   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 379   struct program_space *pspace;
 380   struct inferior *inf;
 381
 382   init_address_spaces ();
 383
 384   if (shared_aspace)
 385     {
 386       struct address_space *aspace = new_address_space ();
 387
 388       free_address_space (current_program_space->aspace);
 389       ALL_PSPACES (pspace)
 390         pspace->aspace = aspace;
 391     }
 392   else
 393     ALL_PSPACES (pspace)
 394       {
 395         free_address_space (pspace->aspace);
 396         pspace->aspace = new_address_space ();
 397       }
 398
 399   for (inf = inferior_list; inf; inf = inf->next)
 400     if (gdbarch_has_global_solist (target_gdbarch ()))
 401       inf->aspace = maybe_new_address_space ();
 402     else
 403       inf->aspace = inf->pspace->aspace;
 404 }
 405
 406 \f
 407
 408 /* See progspace.h.  */
 409
 410 void
 411 clear_program_space_solib_cache (struct program_space *pspace)
 412 {
 413   VEC_free (so_list_ptr, pspace->added_solibs);
 414
 415   free_char_ptr_vec (pspace->deleted_solibs);
 416   pspace->deleted_solibs = NULL;
 417 }
 418
 419 \f
 420
 421 void
 422 initialize_progspace (void)
 423 {
 424   add_cmd ("program-spaces", class_maintenance,
 425            maintenance_info_program_spaces_command,
 426            _("Info about currently known program spaces."),
 427            &maintenanceinfolist);
 428
 429   /* There's always one program space.  Note that this function isn't
 430      an automatic _initialize_foo function, since other
 431      _initialize_foo routines may need to install their per-pspace
 432      data keys.  We can only allocate a progspace when all those
 433      modules have done that.  Do this before
 434      initialize_current_architecture, because that accesses exec_bfd,
 435      which in turn dereferences current_program_space.  */
 436   current_program_space = add_program_space (new_address_space ());
 437 }