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