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 program_space::program_space (address_space *aspace_)
 113 : num (++last_program_space_num), aspace (aspace_)
 114 {
 115   program_space_alloc_data (this);
 116
 117   if (program_spaces == NULL)
 118     program_spaces = this;
 119   else
 120     {
 121       struct program_space *last;
 122
 123       for (last = program_spaces; last->next != NULL; last = last->next)
 124         ;
 125       last->next = this;
 126     }
 127 }
 128
 129 /* Releases program space PSPACE, and all its contents (shared
 130    libraries, objfiles, and any other references to the PSPACE in
 131    other modules).  It is an internal error to call this when PSPACE
 132    is the current program space, since there should always be a
 133    program space.  */
 134
 135 program_space::~program_space ()
 136 {
 137   gdb_assert (this != current_program_space);
 138
 139   scoped_restore_current_program_space restore_pspace;
 140
 141   set_current_program_space (this);
 142
 143   breakpoint_program_space_exit (this);
 144   no_shared_libraries (NULL, 0);
 145   exec_close ();
 146   free_all_objfiles ();
 147   if (!gdbarch_has_shared_address_space (target_gdbarch ()))
 148     free_address_space (this->aspace);
 149   clear_section_table (&this->target_sections);
 150   clear_program_space_solib_cache (this);
 151     /* Discard any data modules have associated with the PSPACE.  */
 152   program_space_free_data (this);
 153 }
 154
 155 /* Copies program space SRC to DEST.  Copies the main executable file,
 156    and the main symbol file.  Returns DEST.  */
 157
 158 struct program_space *
 159 clone_program_space (struct program_space *dest, struct program_space *src)
 160 {
 161   scoped_restore_current_program_space restore_pspace;
 162
 163   set_current_program_space (dest);
 164
 165   if (src->pspace_exec_filename != NULL)
 166     exec_file_attach (src->pspace_exec_filename, 0);
 167
 168   if (src->symfile_object_file != NULL)
 169     symbol_file_add_main (objfile_name (src->symfile_object_file),
 170                           SYMFILE_DEFER_BP_RESET);
 171
 172   return dest;
 173 }
 174
 175 /* Sets PSPACE as the current program space.  It is the caller's
 176    responsibility to make sure that the currently selected
 177    inferior/thread matches the selected program space.  */
 178
 179 void
 180 set_current_program_space (struct program_space *pspace)
 181 {
 182   if (current_program_space == pspace)
 183     return;
 184
 185   gdb_assert (pspace != NULL);
 186
 187   current_program_space = pspace;
 188
 189   /* Different symbols change our view of the frame chain.  */
 190   reinit_frame_cache ();
 191 }
 192
 193 /* Returns true iff there's no inferior bound to PSPACE.  */
 194
 195 int
 196 program_space_empty_p (struct program_space *pspace)
 197 {
 198   if (find_inferior_for_program_space (pspace) != NULL)
 199       return 0;
 200
 201   return 1;
 202 }
 203
 204 /* Remove a program space from the program spaces list and release it.  It is
 205    an error to call this function while PSPACE is the current program space. */
 206
 207 void
 208 delete_program_space (struct program_space *pspace)
 209 {
 210   struct program_space *ss, **ss_link;
 211   gdb_assert (pspace != NULL);
 212   gdb_assert (pspace != current_program_space);
 213
 214   ss = program_spaces;
 215   ss_link = &program_spaces;
 216   while (ss != NULL)
 217     {
 218       if (ss == pspace)
 219         {
 220           *ss_link = ss->next;
 221           break;
 222         }
 223
 224       ss_link = &ss->next;
 225       ss = *ss_link;
 226     }
 227
 228   delete pspace;
 229 }
 230
 231 /* Prints the list of program spaces and their details on UIOUT.  If
 232    REQUESTED is not -1, it's the ID of the pspace that should be
 233    printed.  Otherwise, all spaces are printed.  */
 234
 235 static void
 236 print_program_space (struct ui_out *uiout, int requested)
 237 {
 238   struct program_space *pspace;
 239   int count = 0;
 240
 241   /* Compute number of pspaces we will print.  */
 242   ALL_PSPACES (pspace)
 243     {
 244       if (requested != -1 && pspace->num != requested)
 245         continue;
 246
 247       ++count;
 248     }
 249
 250   /* There should always be at least one.  */
 251   gdb_assert (count > 0);
 252
 253   ui_out_emit_table table_emitter (uiout, 3, count, "pspaces");
 254   uiout->table_header (1, ui_left, "current", "");
 255   uiout->table_header (4, ui_left, "id", "Id");
 256   uiout->table_header (17, ui_left, "exec", "Executable");
 257   uiout->table_body ();
 258
 259   ALL_PSPACES (pspace)
 260     {
 261       struct inferior *inf;
 262       int printed_header;
 263
 264       if (requested != -1 && requested != pspace->num)
 265         continue;
 266
 267       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 268
 269       if (pspace == current_program_space)
 270         uiout->field_string ("current", "*");
 271       else
 272         uiout->field_skip ("current");
 273
 274       uiout->field_int ("id", pspace->num);
 275
 276       if (pspace->pspace_exec_filename)
 277         uiout->field_string ("exec", pspace->pspace_exec_filename);
 278       else
 279         uiout->field_skip ("exec");
 280
 281       /* Print extra info that doesn't really fit in tabular form.
 282          Currently, we print the list of inferiors bound to a pspace.
 283          There can be more than one inferior bound to the same pspace,
 284          e.g., both parent/child inferiors in a vfork, or, on targets
 285          that share pspaces between inferiors.  */
 286       printed_header = 0;
 287       for (inf = inferior_list; inf; inf = inf->next)
 288         if (inf->pspace == pspace)
 289           {
 290             if (!printed_header)
 291               {
 292                 printed_header = 1;
 293                 printf_filtered ("\n\tBound inferiors: ID %d (%s)",
 294                                  inf->num,
 295                                  target_pid_to_str (pid_to_ptid (inf->pid)));
 296               }
 297             else
 298               printf_filtered (", ID %d (%s)",
 299                                inf->num,
 300                                target_pid_to_str (pid_to_ptid (inf->pid)));
 301           }
 302
 303       uiout->text ("\n");
 304     }
 305 }
 306
 307 /* Boolean test for an already-known program space id.  */
 308
 309 static int
 310 valid_program_space_id (int num)
 311 {
 312   struct program_space *pspace;
 313
 314   ALL_PSPACES (pspace)
 315     if (pspace->num == num)
 316       return 1;
 317
 318   return 0;
 319 }
 320
 321 /* If ARGS is NULL or empty, print information about all program
 322    spaces.  Otherwise, ARGS is a text representation of a LONG
 323    indicating which the program space to print information about.  */
 324
 325 static void
 326 maintenance_info_program_spaces_command (const char *args, int from_tty)
 327 {
 328   int requested = -1;
 329
 330   if (args && *args)
 331     {
 332       requested = parse_and_eval_long (args);
 333       if (!valid_program_space_id (requested))
 334         error (_("program space ID %d not known."), requested);
 335     }
 336
 337   print_program_space (current_uiout, requested);
 338 }
 339
 340 /* Simply returns the count of program spaces.  */
 341
 342 int
 343 number_of_program_spaces (void)
 344 {
 345   struct program_space *pspace;
 346   int count = 0;
 347
 348   ALL_PSPACES (pspace)
 349     count++;
 350
 351   return count;
 352 }
 353
 354 /* Update all program spaces matching to address spaces.  The user may
 355    have created several program spaces, and loaded executables into
 356    them before connecting to the target interface that will create the
 357    inferiors.  All that happens before GDB has a chance to know if the
 358    inferiors will share an address space or not.  Call this after
 359    having connected to the target interface and having fetched the
 360    target description, to fixup the program/address spaces mappings.
 361
 362    It is assumed that there are no bound inferiors yet, otherwise,
 363    they'd be left with stale referenced to released aspaces.  */
 364
 365 void
 366 update_address_spaces (void)
 367 {
 368   int shared_aspace = gdbarch_has_shared_address_space (target_gdbarch ());
 369   struct program_space *pspace;
 370   struct inferior *inf;
 371
 372   init_address_spaces ();
 373
 374   if (shared_aspace)
 375     {
 376       struct address_space *aspace = new_address_space ();
 377
 378       free_address_space (current_program_space->aspace);
 379       ALL_PSPACES (pspace)
 380         pspace->aspace = aspace;
 381     }
 382   else
 383     ALL_PSPACES (pspace)
 384       {
 385         free_address_space (pspace->aspace);
 386         pspace->aspace = new_address_space ();
 387       }
 388
 389   for (inf = inferior_list; inf; inf = inf->next)
 390     if (gdbarch_has_global_solist (target_gdbarch ()))
 391       inf->aspace = maybe_new_address_space ();
 392     else
 393       inf->aspace = inf->pspace->aspace;
 394 }
 395
 396 \f
 397
 398 /* See progspace.h.  */
 399
 400 void
 401 clear_program_space_solib_cache (struct program_space *pspace)
 402 {
 403   VEC_free (so_list_ptr, pspace->added_solibs);
 404
 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 }