gdb/thread.c

   1 /* Multi-process/thread control for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1988, 1993, 1998
   3
   4    Contributed by Lynx Real-Time Systems, Inc.  Los Gatos, CA.
   5    Free Software Foundation, Inc.
   6
   7 This file is part of GDB.
   8
   9 This program is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2 of the License, or
  12 (at your option) any later version.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  22
  23 #include "defs.h"
  24 #include "symtab.h"
  25 #include "frame.h"
  26 #include "inferior.h"
  27 #include "environ.h"
  28 #include "value.h"
  29 #include "target.h"
  30 #include "gdbthread.h"
  31 #include "command.h"
  32 #include "gdbcmd.h"
  33
  34 #include <ctype.h>
  35 #include <sys/types.h>
  36 #include <signal.h>
  37
  38 /*#include "lynxos-core.h"*/
  39
  40 struct thread_info
  41 {
  42   struct thread_info *next;
  43   int pid;                      /* Actual process id */
  44   int num;                      /* Convenient handle */
  45   CORE_ADDR prev_pc;            /* State from wait_for_inferior */
  46   CORE_ADDR prev_func_start;
  47   char *prev_func_name;
  48   struct breakpoint *step_resume_breakpoint;
  49   struct breakpoint *through_sigtramp_breakpoint;
  50   CORE_ADDR step_range_start;
  51   CORE_ADDR step_range_end;
  52   CORE_ADDR step_frame_address;
  53   int trap_expected;
  54   int handling_longjmp;
  55   int another_trap;
  56 };
  57
  58 static struct thread_info *thread_list = NULL;
  59 static int highest_thread_num;
  60
  61 /* Prototypes for exported functions. */
  62
  63 void _initialize_thread PARAMS ((void));
  64
  65 /* Prototypes for local functions. */
  66
  67 static void thread_command PARAMS ((char * tidstr, int from_tty));
  68
  69 static void prune_threads PARAMS ((void));
  70
  71 static void switch_to_thread PARAMS ((int pid));
  72
  73 static struct thread_info *find_thread_id PARAMS ((int num));
  74
  75 static void info_threads_command PARAMS ((char *, int));
  76
  77 static void restore_current_thread PARAMS ((int));
  78
  79 static void thread_apply_all_command PARAMS ((char *, int));
  80
  81 static void thread_apply_command PARAMS ((char *, int));
  82
  83 static int thread_alive PARAMS ((struct thread_info *));
  84
  85 void
  86 init_thread_list ()
  87 {
  88   struct thread_info *tp, *tpnext;
  89
  90   if (!thread_list)
  91     return;
  92
  93   for (tp = thread_list; tp; tp = tpnext)
  94     {
  95       tpnext = tp->next;
  96       free (tp);
  97     }
  98
  99   thread_list = NULL;
 100   highest_thread_num = 0;
 101 }
 102
 103 void
 104 add_thread (pid)
 105      int pid;
 106 {
 107   struct thread_info *tp;
 108
 109   tp = (struct thread_info *) xmalloc (sizeof (struct thread_info));
 110
 111   tp->pid = pid;
 112   tp->num = ++highest_thread_num;
 113   tp->prev_pc = 0;
 114   tp->prev_func_start = 0;
 115   tp->prev_func_name = NULL;
 116   tp->step_range_start = 0;
 117   tp->step_range_end = 0;
 118   tp->step_frame_address =0;
 119   tp->step_resume_breakpoint = 0;
 120   tp->through_sigtramp_breakpoint = 0;
 121   tp->handling_longjmp = 0;
 122   tp->trap_expected = 0;
 123   tp->another_trap = 0;
 124   tp->next = thread_list;
 125   thread_list = tp;
 126 }
 127
 128 void
 129 delete_thread (pid)
 130      int pid;
 131 {
 132   struct thread_info *tp, *tpprev;
 133
 134   tpprev = NULL;
 135
 136   for (tp = thread_list; tp; tpprev = tp, tp = tp->next)
 137     if (tp->pid == pid)
 138       break;
 139
 140   if (!tp)
 141     return;
 142
 143   if (tpprev)
 144     tpprev->next = tp->next;
 145   else
 146     thread_list = tp->next;
 147
 148   free (tp);
 149
 150   return;
 151 }
 152
 153 static struct thread_info *
 154 find_thread_id (num)
 155     int num;
 156 {
 157   struct thread_info *tp;
 158
 159   for (tp = thread_list; tp; tp = tp->next)
 160     if (tp->num == num)
 161       return tp;
 162
 163   return NULL;
 164 }
 165
 166 int
 167 valid_thread_id (num)
 168     int num;
 169 {
 170   struct thread_info *tp;
 171
 172   for (tp = thread_list; tp; tp = tp->next)
 173     if (tp->num == num)
 174       return 1;
 175
 176   return 0;
 177 }
 178
 179 int
 180 pid_to_thread_id (pid)
 181     int pid;
 182 {
 183   struct thread_info *tp;
 184
 185   for (tp = thread_list; tp; tp = tp->next)
 186     if (tp->pid == pid)
 187       return tp->num;
 188
 189   return 0;
 190 }
 191
 192 int
 193 thread_id_to_pid (num)
 194     int num;
 195 {
 196   struct thread_info *thread = find_thread_id (num);
 197   if (thread)
 198     return thread->pid;
 199   else
 200     return -1;
 201 }
 202
 203 int
 204 in_thread_list (pid)
 205     int pid;
 206 {
 207   struct thread_info *tp;
 208
 209   for (tp = thread_list; tp; tp = tp->next)
 210     if (tp->pid == pid)
 211       return 1;
 212
 213   return 0;                     /* Never heard of 'im */
 214 }
 215
 216 /* Load infrun state for the thread PID.  */
 217
 218 void load_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 219                         trap_expected, step_resume_breakpoint,
 220                         through_sigtramp_breakpoint, step_range_start,
 221                         step_range_end, step_frame_address,
 222                         handling_longjmp, another_trap)
 223      int pid;
 224      CORE_ADDR *prev_pc;
 225      CORE_ADDR *prev_func_start;
 226      char **prev_func_name;
 227      int *trap_expected;
 228      struct breakpoint **step_resume_breakpoint;
 229      struct breakpoint **through_sigtramp_breakpoint;
 230      CORE_ADDR *step_range_start;
 231      CORE_ADDR *step_range_end;
 232      CORE_ADDR *step_frame_address;
 233      int *handling_longjmp;
 234      int *another_trap;
 235 {
 236   struct thread_info *tp;
 237
 238   /* If we can't find the thread, then we're debugging a single threaded
 239      process.  No need to do anything in that case.  */
 240   tp = find_thread_id (pid_to_thread_id (pid));
 241   if (tp == NULL)
 242     return;
 243
 244   *prev_pc = tp->prev_pc;
 245   *prev_func_start = tp->prev_func_start;
 246   *prev_func_name = tp->prev_func_name;
 247   *step_resume_breakpoint = tp->step_resume_breakpoint;
 248   *step_range_start = tp->step_range_start;
 249   *step_range_end = tp->step_range_end;
 250   *step_frame_address = tp->step_frame_address;
 251   *through_sigtramp_breakpoint = tp->through_sigtramp_breakpoint;
 252   *handling_longjmp = tp->handling_longjmp;
 253   *trap_expected = tp->trap_expected;
 254   *another_trap = tp->another_trap;
 255 }
 256
 257 /* Save infrun state for the thread PID.  */
 258
 259 void save_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 260                         trap_expected, step_resume_breakpoint,
 261                         through_sigtramp_breakpoint, step_range_start,
 262                         step_range_end, step_frame_address,
 263                         handling_longjmp, another_trap)
 264      int pid;
 265      CORE_ADDR prev_pc;
 266      CORE_ADDR prev_func_start;
 267      char *prev_func_name;
 268      int trap_expected;
 269      struct breakpoint *step_resume_breakpoint;
 270      struct breakpoint *through_sigtramp_breakpoint;
 271      CORE_ADDR step_range_start;
 272      CORE_ADDR step_range_end;
 273      CORE_ADDR step_frame_address;
 274      int handling_longjmp;
 275      int another_trap;
 276 {
 277   struct thread_info *tp;
 278
 279   /* If we can't find the thread, then we're debugging a single-threaded
 280      process.  Nothing to do in that case.  */
 281   tp = find_thread_id (pid_to_thread_id (pid));
 282   if (tp == NULL)
 283     return;
 284
 285   tp->prev_pc = prev_pc;
 286   tp->prev_func_start = prev_func_start;
 287   tp->prev_func_name = prev_func_name;
 288   tp->step_resume_breakpoint = step_resume_breakpoint;
 289   tp->step_range_start = step_range_start;
 290   tp->step_range_end = step_range_end;
 291   tp->step_frame_address = step_frame_address;
 292   tp->through_sigtramp_breakpoint = through_sigtramp_breakpoint;
 293   tp->handling_longjmp = handling_longjmp;
 294   tp->trap_expected = trap_expected;
 295   tp->another_trap = another_trap;
 296 }
 297
 298 /* Return true if TP is an active thread. */
 299 static int
 300 thread_alive (tp)
 301      struct thread_info *tp;
 302 {
 303   if (tp->pid == -1)
 304     return 0;
 305   if (! target_thread_alive (tp->pid))
 306     {
 307       tp->pid = -1;     /* Mark it as dead */
 308       return 0;
 309     }
 310   return 1;
 311 }
 312
 313 static void
 314 prune_threads ()
 315 {
 316   struct thread_info *tp, *tpprev, *next;
 317
 318   tpprev = 0;
 319   for (tp = thread_list; tp; tp = next)
 320     {
 321       next = tp->next;
 322       if (!thread_alive (tp))
 323         {
 324           if (tpprev)
 325             tpprev->next = next;
 326           else
 327             thread_list  = next;
 328           free (tp);
 329         }
 330       else
 331         tpprev = tp;
 332     }
 333 }
 334
 335 /* Print information about currently known threads */
 336
 337 static void
 338 info_threads_command (arg, from_tty)
 339      char *arg;
 340      int from_tty;
 341 {
 342   struct thread_info *tp;
 343   int current_pid = inferior_pid;
 344
 345   /* Avoid coredumps which would happen if we tried to access a NULL
 346      selected_frame.  */
 347   if (!target_has_stack) error ("No stack.");
 348
 349   prune_threads ();
 350 #if defined(FIND_NEW_THREADS)
 351   FIND_NEW_THREADS ();
 352 #endif
 353
 354   for (tp = thread_list; tp; tp = tp->next)
 355     {
 356       if (tp->pid == current_pid)
 357         printf_filtered ("* ");
 358       else
 359         printf_filtered ("  ");
 360
 361       printf_filtered ("%d %s  ", tp->num, target_pid_to_str (tp->pid));
 362
 363       switch_to_thread (tp->pid);
 364       if (selected_frame)
 365         print_stack_frame (selected_frame, -1, 0);
 366       else
 367         printf_filtered ("[No stack.]\n");
 368     }
 369
 370   switch_to_thread (current_pid);
 371 }
 372
 373 /* Switch from one thread to another. */
 374
 375 static void
 376 switch_to_thread (pid)
 377      int pid;
 378 {
 379   if (pid == inferior_pid)
 380     return;
 381
 382   inferior_pid = pid;
 383   flush_cached_frames ();
 384   registers_changed ();
 385   stop_pc = read_pc();
 386   select_frame (get_current_frame (), 0);
 387 }
 388
 389 static void
 390 restore_current_thread (pid)
 391      int pid;
 392 {
 393   if (pid != inferior_pid)
 394     switch_to_thread (pid);
 395 }
 396
 397 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
 398    seperated list of numbers, or ranges, or the keyword `all'.  Ranges consist
 399    of two numbers seperated by a hyphen.  Examples:
 400
 401         thread apply 1 2 7 4 backtrace  Apply backtrace cmd to threads 1,2,7,4
 402         thread apply 2-7 9 p foo(1)     Apply p foo(1) cmd to threads 2->7 & 9
 403         thread apply all p x/i $pc      Apply x/i $pc cmd to all threads
 404 */
 405
 406 static void
 407 thread_apply_all_command (cmd, from_tty)
 408      char *cmd;
 409      int from_tty;
 410 {
 411   struct thread_info *tp;
 412   struct cleanup *old_chain;
 413
 414   if (cmd == NULL || *cmd == '\000')
 415     error ("Please specify a command following the thread ID list");
 416
 417   old_chain = make_cleanup ((make_cleanup_func) restore_current_thread,
 418                             (void *) inferior_pid);
 419
 420   for (tp = thread_list; tp; tp = tp->next)
 421     if (thread_alive (tp))
 422       {
 423         switch_to_thread (tp->pid);
 424         printf_filtered ("\nThread %d (%s):\n", tp->num,
 425                          target_pid_to_str (inferior_pid));
 426         execute_command (cmd, from_tty);
 427       }
 428 }
 429
 430 static void
 431 thread_apply_command (tidlist, from_tty)
 432      char *tidlist;
 433      int from_tty;
 434 {
 435   char *cmd;
 436   char *p;
 437   struct cleanup *old_chain;
 438
 439   if (tidlist == NULL || *tidlist == '\000')
 440     error ("Please specify a thread ID list");
 441
 442   for (cmd = tidlist; *cmd != '\000' && !isalpha(*cmd); cmd++);
 443
 444   if (*cmd == '\000')
 445     error ("Please specify a command following the thread ID list");
 446
 447   old_chain = make_cleanup ((make_cleanup_func) restore_current_thread,
 448                             (void *) inferior_pid);
 449
 450   while (tidlist < cmd)
 451     {
 452       struct thread_info *tp;
 453       int start, end;
 454
 455       start = strtol (tidlist, &p, 10);
 456       if (p == tidlist)
 457         error ("Error parsing %s", tidlist);
 458       tidlist = p;
 459
 460       while (*tidlist == ' ' || *tidlist == '\t')
 461         tidlist++;
 462
 463       if (*tidlist == '-')      /* Got a range of IDs? */
 464         {
 465           tidlist++;    /* Skip the - */
 466           end = strtol (tidlist, &p, 10);
 467           if (p == tidlist)
 468             error ("Error parsing %s", tidlist);
 469           tidlist = p;
 470
 471           while (*tidlist == ' ' || *tidlist == '\t')
 472             tidlist++;
 473         }
 474       else
 475         end = start;
 476
 477       for (; start <= end; start++)
 478         {
 479           tp = find_thread_id (start);
 480
 481           if (!tp)
 482             warning ("Unknown thread %d.", start);
 483           else if (!thread_alive (tp))
 484             warning ("Thread %d has terminated.", start);
 485           else
 486             {
 487               switch_to_thread (tp->pid);
 488               printf_filtered ("\nThread %d (%s):\n", tp->num,
 489                                target_pid_to_str (inferior_pid));
 490               execute_command (cmd, from_tty);
 491             }
 492         }
 493     }
 494 }
 495
 496 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
 497    if prefix of arg is `apply'.  */
 498
 499 static void
 500 thread_command (tidstr, from_tty)
 501      char *tidstr;
 502      int from_tty;
 503 {
 504   int num;
 505   struct thread_info *tp;
 506
 507   if (!tidstr)
 508     error ("Please specify a thread ID.  Use the \"info threads\" command to\n\
 509 see the IDs of currently known threads.");
 510
 511   num = atoi (tidstr);
 512
 513   tp = find_thread_id (num);
 514
 515   if (!tp)
 516     error ("Thread ID %d not known.  Use the \"info threads\" command to\n\
 517 see the IDs of currently known threads.", num);
 518
 519   if (!thread_alive (tp))
 520     error ("Thread ID %d has terminated.\n", num);
 521
 522   switch_to_thread (tp->pid);
 523   if (context_hook)
 524     context_hook (num);
 525   printf_filtered ("[Switching to %s]\n", target_pid_to_str (inferior_pid));
 526   print_stack_frame (selected_frame, selected_frame_level, 1);
 527 }
 528
 529 /* Commands with a prefix of `thread'.  */
 530 struct cmd_list_element *thread_cmd_list = NULL;
 531
 532 void
 533 _initialize_thread ()
 534 {
 535   static struct cmd_list_element *thread_apply_list = NULL;
 536   extern struct cmd_list_element *cmdlist;
 537
 538   add_info ("threads", info_threads_command,
 539             "IDs of currently known threads.");
 540
 541   add_prefix_cmd ("thread", class_run, thread_command,
 542                   "Use this command to switch between threads.\n\
 543 The new thread ID must be currently known.", &thread_cmd_list, "thread ", 1,
 544                   &cmdlist);
 545
 546   add_prefix_cmd ("apply", class_run, thread_apply_command,
 547                   "Apply a command to a list of threads.",
 548                   &thread_apply_list, "apply ", 1, &thread_cmd_list);
 549
 550   add_cmd ("all", class_run, thread_apply_all_command,
 551            "Apply a command to all threads.",
 552            &thread_apply_list);
 553
 554   add_com_alias ("t", "thread", class_run, 1);
 555 }