gdb/gdbserver/inferiors.c

   1 /* Inferior process information for the remote server for GDB.
   2    Copyright (C) 2002-2016 Free Software Foundation, Inc.
   3
   4    Contributed by MontaVista Software.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include "server.h"
  22 #include "gdbthread.h"
  23 #include "dll.h"
  24
  25 struct inferior_list all_processes;
  26 struct inferior_list all_threads;
  27
  28 struct thread_info *current_thread;
  29
  30 #define get_thread(inf) ((struct thread_info *)(inf))
  31
  32 void
  33 add_inferior_to_list (struct inferior_list *list,
  34                       struct inferior_list_entry *new_inferior)
  35 {
  36   new_inferior->next = NULL;
  37   if (list->tail != NULL)
  38     list->tail->next = new_inferior;
  39   else
  40     list->head = new_inferior;
  41   list->tail = new_inferior;
  42 }
  43
  44 /* Invoke ACTION for each inferior in LIST.  */
  45
  46 void
  47 for_each_inferior (struct inferior_list *list,
  48                    void (*action) (struct inferior_list_entry *))
  49 {
  50   struct inferior_list_entry *cur = list->head, *next;
  51
  52   while (cur != NULL)
  53     {
  54       next = cur->next;
  55       (*action) (cur);
  56       cur = next;
  57     }
  58 }
  59
  60 /* Invoke ACTION for each inferior in LIST, passing DATA to ACTION.  */
  61
  62 void
  63 for_each_inferior_with_data (struct inferior_list *list,
  64                              void (*action) (struct inferior_list_entry *,
  65                                              void *),
  66                              void *data)
  67 {
  68   struct inferior_list_entry *cur = list->head, *next;
  69
  70   while (cur != NULL)
  71     {
  72       next = cur->next;
  73       (*action) (cur, data);
  74       cur = next;
  75     }
  76 }
  77
  78 void
  79 remove_inferior (struct inferior_list *list,
  80                  struct inferior_list_entry *entry)
  81 {
  82   struct inferior_list_entry **cur;
  83
  84   if (list->head == entry)
  85     {
  86       list->head = entry->next;
  87       if (list->tail == entry)
  88         list->tail = list->head;
  89       return;
  90     }
  91
  92   cur = &list->head;
  93   while (*cur && (*cur)->next != entry)
  94     cur = &(*cur)->next;
  95
  96   if (*cur == NULL)
  97     return;
  98
  99   (*cur)->next = entry->next;
 100
 101   if (list->tail == entry)
 102     list->tail = *cur;
 103 }
 104
 105 struct thread_info *
 106 add_thread (ptid_t thread_id, void *target_data)
 107 {
 108   struct thread_info *new_thread = XCNEW (struct thread_info);
 109
 110   new_thread->entry.id = thread_id;
 111   new_thread->last_resume_kind = resume_continue;
 112   new_thread->last_status.kind = TARGET_WAITKIND_IGNORE;
 113
 114   add_inferior_to_list (&all_threads, &new_thread->entry);
 115
 116   if (current_thread == NULL)
 117     current_thread = new_thread;
 118
 119   new_thread->target_data = target_data;
 120
 121   return new_thread;
 122 }
 123
 124 ptid_t
 125 thread_to_gdb_id (struct thread_info *thread)
 126 {
 127   return thread->entry.id;
 128 }
 129
 130 /* Wrapper around get_first_inferior to return a struct thread_info *.  */
 131
 132 struct thread_info *
 133 get_first_thread (void)
 134 {
 135   return (struct thread_info *) get_first_inferior (&all_threads);
 136 }
 137
 138 struct thread_info *
 139 find_thread_ptid (ptid_t ptid)
 140 {
 141   return (struct thread_info *) find_inferior_id (&all_threads, ptid);
 142 }
 143
 144 /* Predicate function for matching thread entry's pid to the given
 145    pid value passed by address in ARGS.  */
 146
 147 static int
 148 thread_pid_matches_callback (struct inferior_list_entry *entry, void *args)
 149 {
 150   return (ptid_get_pid (entry->id) == *(pid_t *)args);
 151 }
 152
 153 /* Find a thread associated with the given PROCESS, or NULL if no
 154    such thread exists.  */
 155
 156 static struct thread_info *
 157 find_thread_process (const struct process_info *const process)
 158 {
 159   pid_t pid = ptid_get_pid (ptid_of (process));
 160
 161   return (struct thread_info *)
 162     find_inferior (&all_threads, thread_pid_matches_callback, &pid);
 163 }
 164
 165 /* Helper for find_any_thread_of_pid.  Returns true if a thread
 166    matches a PID.  */
 167
 168 static int
 169 thread_of_pid (struct inferior_list_entry *entry, void *pid_p)
 170 {
 171   int pid = *(int *) pid_p;
 172
 173   return (ptid_get_pid (entry->id) == pid);
 174 }
 175
 176 /* See gdbthread.h.  */
 177
 178 struct thread_info *
 179 find_any_thread_of_pid (int pid)
 180 {
 181   struct inferior_list_entry *entry;
 182
 183   entry = find_inferior (&all_threads, thread_of_pid, &pid);
 184
 185   return (struct thread_info *) entry;
 186 }
 187
 188 ptid_t
 189 gdb_id_to_thread_id (ptid_t gdb_id)
 190 {
 191   struct thread_info *thread = find_thread_ptid (gdb_id);
 192
 193   return thread ? thread->entry.id : null_ptid;
 194 }
 195
 196 static void
 197 free_one_thread (struct inferior_list_entry *inf)
 198 {
 199   struct thread_info *thread = get_thread (inf);
 200   free_register_cache (inferior_regcache_data (thread));
 201   free (thread);
 202 }
 203
 204 void
 205 remove_thread (struct thread_info *thread)
 206 {
 207   if (thread->btrace != NULL)
 208     target_disable_btrace (thread->btrace);
 209
 210   discard_queued_stop_replies (ptid_of (thread));
 211   remove_inferior (&all_threads, (struct inferior_list_entry *) thread);
 212   free_one_thread (&thread->entry);
 213   if (current_thread == thread)
 214     current_thread = NULL;
 215 }
 216
 217 /* Return a pointer to the first inferior in LIST, or NULL if there isn't one.
 218    This is for cases where the caller needs a thread, but doesn't care
 219    which one.  */
 220
 221 struct inferior_list_entry *
 222 get_first_inferior (struct inferior_list *list)
 223 {
 224   if (list->head != NULL)
 225     return list->head;
 226   return NULL;
 227 }
 228
 229 /* Find the first inferior_list_entry E in LIST for which FUNC (E, ARG)
 230    returns non-zero.  If no entry is found then return NULL.  */
 231
 232 struct inferior_list_entry *
 233 find_inferior (struct inferior_list *list,
 234                int (*func) (struct inferior_list_entry *, void *), void *arg)
 235 {
 236   struct inferior_list_entry *inf = list->head;
 237
 238   while (inf != NULL)
 239     {
 240       struct inferior_list_entry *next;
 241
 242       next = inf->next;
 243       if ((*func) (inf, arg))
 244         return inf;
 245       inf = next;
 246     }
 247
 248   return NULL;
 249 }
 250
 251 struct inferior_list_entry *
 252 find_inferior_id (struct inferior_list *list, ptid_t id)
 253 {
 254   struct inferior_list_entry *inf = list->head;
 255
 256   while (inf != NULL)
 257     {
 258       if (ptid_equal (inf->id, id))
 259         return inf;
 260       inf = inf->next;
 261     }
 262
 263   return NULL;
 264 }
 265
 266 void *
 267 inferior_target_data (struct thread_info *inferior)
 268 {
 269   return inferior->target_data;
 270 }
 271
 272 void
 273 set_inferior_target_data (struct thread_info *inferior, void *data)
 274 {
 275   inferior->target_data = data;
 276 }
 277
 278 struct regcache *
 279 inferior_regcache_data (struct thread_info *inferior)
 280 {
 281   return inferior->regcache_data;
 282 }
 283
 284 void
 285 set_inferior_regcache_data (struct thread_info *inferior, struct regcache *data)
 286 {
 287   inferior->regcache_data = data;
 288 }
 289
 290 /* Return true if LIST has exactly one entry.  */
 291
 292 int
 293 one_inferior_p (struct inferior_list *list)
 294 {
 295   return list->head != NULL && list->head == list->tail;
 296 }
 297
 298 /* Reset head,tail of LIST, assuming all entries have already been freed.  */
 299
 300 void
 301 clear_inferior_list (struct inferior_list *list)
 302 {
 303   list->head = NULL;
 304   list->tail = NULL;
 305 }
 306
 307 void
 308 clear_inferiors (void)
 309 {
 310   for_each_inferior (&all_threads, free_one_thread);
 311   clear_inferior_list (&all_threads);
 312
 313   clear_dlls ();
 314
 315   current_thread = NULL;
 316 }
 317
 318 struct process_info *
 319 add_process (int pid, int attached)
 320 {
 321   struct process_info *process = XCNEW (struct process_info);
 322
 323   process->entry.id = pid_to_ptid (pid);
 324   process->attached = attached;
 325
 326   add_inferior_to_list (&all_processes, &process->entry);
 327
 328   return process;
 329 }
 330
 331 /* Remove a process from the common process list and free the memory
 332    allocated for it.
 333    The caller is responsible for freeing private data first.  */
 334
 335 void
 336 remove_process (struct process_info *process)
 337 {
 338   clear_symbol_cache (&process->symbol_cache);
 339   free_all_breakpoints (process);
 340   gdb_assert (find_thread_process (process) == NULL);
 341   remove_inferior (&all_processes, &process->entry);
 342   free (process);
 343 }
 344
 345 struct process_info *
 346 find_process_pid (int pid)
 347 {
 348   return (struct process_info *)
 349     find_inferior_id (&all_processes, pid_to_ptid (pid));
 350 }
 351
 352 /* Wrapper around get_first_inferior to return a struct process_info *.  */
 353
 354 struct process_info *
 355 get_first_process (void)
 356 {
 357   return (struct process_info *) get_first_inferior (&all_processes);
 358 }
 359
 360 /* Return non-zero if INF, a struct process_info, was started by us,
 361    i.e. not attached to.  */
 362
 363 static int
 364 started_inferior_callback (struct inferior_list_entry *entry, void *args)
 365 {
 366   struct process_info *process = (struct process_info *) entry;
 367
 368   return ! process->attached;
 369 }
 370
 371 /* Return non-zero if there are any inferiors that we have created
 372    (as opposed to attached-to).  */
 373
 374 int
 375 have_started_inferiors_p (void)
 376 {
 377   return (find_inferior (&all_processes, started_inferior_callback, NULL)
 378           != NULL);
 379 }
 380
 381 /* Return non-zero if INF, a struct process_info, was attached to.  */
 382
 383 static int
 384 attached_inferior_callback (struct inferior_list_entry *entry, void *args)
 385 {
 386   struct process_info *process = (struct process_info *) entry;
 387
 388   return process->attached;
 389 }
 390
 391 /* Return non-zero if there are any inferiors that we have attached to.  */
 392
 393 int
 394 have_attached_inferiors_p (void)
 395 {
 396   return (find_inferior (&all_processes, attached_inferior_callback, NULL)
 397           != NULL);
 398 }
 399
 400 struct process_info *
 401 get_thread_process (struct thread_info *thread)
 402 {
 403   int pid = ptid_get_pid (thread->entry.id);
 404   return find_process_pid (pid);
 405 }
 406
 407 struct process_info *
 408 current_process (void)
 409 {
 410   gdb_assert (current_thread != NULL);
 411   return get_thread_process (current_thread);
 412 }