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 static void
  62 thread_command PARAMS ((char * tidstr, int from_tty));
  63
  64 static void
  65 prune_threads PARAMS ((void));
  66
  67 static void
  68 switch_to_thread PARAMS ((int pid));
  69
  70 static struct thread_info *
  71 find_thread_id PARAMS ((int num));
  72
  73 static void
  74 info_threads_command PARAMS ((char *, int));
  75
  76 static void
  77 restore_current_thread PARAMS ((int));
  78
  79 static void
  80 thread_apply_all_command PARAMS ((char *, int));
  81
  82 static void
  83 thread_apply_command PARAMS ((char *, int));
  84
  85 static int
  86 thread_alive PARAMS ((struct thread_info *));
  87
  88 void
  89 init_thread_list ()
  90 {
  91   struct thread_info *tp, *tpnext;
  92
  93   if (!thread_list)
  94     return;
  95
  96   for (tp = thread_list; tp; tp = tpnext)
  97     {
  98       tpnext = tp->next;
  99       free (tp);
 100     }
 101
 102   thread_list = NULL;
 103   highest_thread_num = 0;
 104 }
 105
 106 void
 107 add_thread (pid)
 108      int pid;
 109 {
 110   struct thread_info *tp;
 111
 112   tp = (struct thread_info *) xmalloc (sizeof (struct thread_info));
 113
 114   tp->pid = pid;
 115   tp->num = ++highest_thread_num;
 116   tp->prev_pc = 0;
 117   tp->prev_func_start = 0;
 118   tp->prev_func_name = NULL;
 119   tp->step_range_start = 0;
 120   tp->step_range_end = 0;
 121   tp->step_frame_address =0;
 122   tp->step_resume_breakpoint = 0;
 123   tp->through_sigtramp_breakpoint = 0;
 124   tp->handling_longjmp = 0;
 125   tp->trap_expected = 0;
 126   tp->another_trap = 0;
 127   tp->next = thread_list;
 128   thread_list = tp;
 129 }
 130
 131 void
 132 delete_thread (pid)
 133      int pid;
 134 {
 135   struct thread_info *tp, *tpprev;
 136
 137   tpprev = NULL;
 138
 139   for (tp = thread_list; tp; tpprev = tp, tp = tp->next)
 140     if (tp->pid == pid)
 141       break;
 142
 143   if (!tp)
 144     return;
 145
 146   if (tpprev)
 147     tpprev->next = tp->next;
 148   else
 149     thread_list = tp->next;
 150
 151   free (tp);
 152
 153   return;
 154 }
 155
 156 static struct thread_info *
 157 find_thread_id (num)
 158     int num;
 159 {
 160   struct thread_info *tp;
 161
 162   for (tp = thread_list; tp; tp = tp->next)
 163     if (tp->num == num)
 164       return tp;
 165
 166   return NULL;
 167 }
 168
 169 int
 170 valid_thread_id (num)
 171     int num;
 172 {
 173   struct thread_info *tp;
 174
 175   for (tp = thread_list; tp; tp = tp->next)
 176     if (tp->num == num)
 177       return 1;
 178
 179   return 0;
 180 }
 181
 182 int
 183 pid_to_thread_id (pid)
 184     int pid;
 185 {
 186   struct thread_info *tp;
 187
 188   for (tp = thread_list; tp; tp = tp->next)
 189     if (tp->pid == pid)
 190       return tp->num;
 191
 192   return 0;
 193 }
 194
 195 int
 196 thread_id_to_pid (num)
 197     int num;
 198 {
 199   struct thread_info *thread = find_thread_id (num);
 200   if (thread)
 201     return thread->pid;
 202   else
 203     return -1;
 204 }
 205
 206 int
 207 in_thread_list (pid)
 208     int pid;
 209 {
 210   struct thread_info *tp;
 211
 212   for (tp = thread_list; tp; tp = tp->next)
 213     if (tp->pid == pid)
 214       return 1;
 215
 216   return 0;                     /* Never heard of 'im */
 217 }
 218
 219 /* Load infrun state for the thread PID.  */
 220
 221 void load_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 222                         trap_expected, step_resume_breakpoint,
 223                         through_sigtramp_breakpoint, step_range_start,
 224                         step_range_end, step_frame_address,
 225                         handling_longjmp, another_trap)
 226      int pid;
 227      CORE_ADDR *prev_pc;
 228      CORE_ADDR *prev_func_start;
 229      char **prev_func_name;
 230      int *trap_expected;
 231      struct breakpoint **step_resume_breakpoint;
 232      struct breakpoint **through_sigtramp_breakpoint;
 233      CORE_ADDR *step_range_start;
 234      CORE_ADDR *step_range_end;
 235      CORE_ADDR *step_frame_address;
 236      int *handling_longjmp;
 237      int *another_trap;
 238 {
 239   struct thread_info *tp;
 240
 241   /* If we can't find the thread, then we're debugging a single threaded
 242      process.  No need to do anything in that case.  */
 243   tp = find_thread_id (pid_to_thread_id (pid));
 244   if (tp == NULL)
 245     return;
 246
 247   *prev_pc = tp->prev_pc;
 248   *prev_func_start = tp->prev_func_start;
 249   *prev_func_name = tp->prev_func_name;
 250   *step_resume_breakpoint = tp->step_resume_breakpoint;
 251   *step_range_start = tp->step_range_start;
 252   *step_range_end = tp->step_range_end;
 253   *step_frame_address = tp->step_frame_address;
 254   *through_sigtramp_breakpoint = tp->through_sigtramp_breakpoint;
 255   *handling_longjmp = tp->handling_longjmp;
 256   *trap_expected = tp->trap_expected;
 257   *another_trap = tp->another_trap;
 258 }
 259
 260 /* Save infrun state for the thread PID.  */
 261
 262 void save_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 263                         trap_expected, step_resume_breakpoint,
 264                         through_sigtramp_breakpoint, step_range_start,
 265                         step_range_end, step_frame_address,
 266                         handling_longjmp, another_trap)
 267      int pid;
 268      CORE_ADDR prev_pc;
 269      CORE_ADDR prev_func_start;
 270      char *prev_func_name;
 271      int trap_expected;
 272      struct breakpoint *step_resume_breakpoint;
 273      struct breakpoint *through_sigtramp_breakpoint;
 274      CORE_ADDR step_range_start;
 275      CORE_ADDR step_range_end;
 276      CORE_ADDR step_frame_address;
 277      int handling_longjmp;
 278      int another_trap;
 279 {
 280   struct thread_info *tp;
 281
 282   /* If we can't find the thread, then we're debugging a single-threaded
 283      process.  Nothing to do in that case.  */
 284   tp = find_thread_id (pid_to_thread_id (pid));
 285   if (tp == NULL)
 286     return;
 287
 288   tp->prev_pc = prev_pc;
 289   tp->prev_func_start = prev_func_start;
 290   tp->prev_func_name = prev_func_name;
 291   tp->step_resume_breakpoint = step_resume_breakpoint;
 292   tp->step_range_start = step_range_start;
 293   tp->step_range_end = step_range_end;
 294   tp->step_frame_address = step_frame_address;
 295   tp->through_sigtramp_breakpoint = through_sigtramp_breakpoint;
 296   tp->handling_longjmp = handling_longjmp;
 297   tp->trap_expected = trap_expected;
 298   tp->another_trap = another_trap;
 299 }
 300
 301 /* Return true if TP is an active thread. */
 302 static int
 303 thread_alive (tp)
 304      struct thread_info *tp;
 305 {
 306   if (tp->pid == -1)
 307     return 0;
 308   if (! target_thread_alive (tp->pid))
 309     {
 310       tp->pid = -1;     /* Mark it as dead */
 311       return 0;
 312     }
 313   return 1;
 314 }
 315
 316 static void
 317 prune_threads ()
 318 {
 319   struct thread_info *tp, *tpprev, *next;
 320
 321   tpprev = 0;
 322   for (tp = thread_list; tp; tp = next)
 323     {
 324       next = tp->next;
 325       if (!thread_alive (tp))
 326         {
 327           if (tpprev)
 328             tpprev->next = next;
 329           else
 330             thread_list  = next;
 331           free (tp);
 332         }
 333       else
 334         tpprev = tp;
 335     }
 336 }
 337
 338 /* Print information about currently known threads */
 339
 340 static void
 341 info_threads_command (arg, from_tty)
 342      char *arg;
 343      int from_tty;
 344 {
 345   struct thread_info *tp;
 346   int current_pid = inferior_pid;
 347
 348   /* Avoid coredumps which would happen if we tried to access a NULL
 349      selected_frame.  */
 350   if (!target_has_stack) error ("No stack.");
 351
 352   prune_threads ();
 353 #if defined(FIND_NEW_THREADS)
 354   FIND_NEW_THREADS ();
 355 #endif
 356
 357   for (tp = thread_list; tp; tp = tp->next)
 358     {
 359       if (tp->pid == current_pid)
 360         printf_filtered ("* ");
 361       else
 362         printf_filtered ("  ");
 363
 364       printf_filtered ("%d %s  ", tp->num, target_pid_to_str (tp->pid));
 365
 366       switch_to_thread (tp->pid);
 367       if (selected_frame)
 368         print_stack_frame (selected_frame, -1, 0);
 369       else
 370         printf_filtered ("[No stack.]\n");
 371     }
 372
 373   switch_to_thread (current_pid);
 374 }
 375
 376 /* Switch from one thread to another. */
 377
 378 static void
 379 switch_to_thread (pid)
 380      int pid;
 381 {
 382   if (pid == inferior_pid)
 383     return;
 384
 385   inferior_pid = pid;
 386   flush_cached_frames ();
 387   registers_changed ();
 388   stop_pc = read_pc();
 389   select_frame (get_current_frame (), 0);
 390 }
 391
 392 static void
 393 restore_current_thread (pid)
 394      int pid;
 395 {
 396   if (pid != inferior_pid)
 397     switch_to_thread (pid);
 398 }
 399
 400 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
 401    seperated list of numbers, or ranges, or the keyword `all'.  Ranges consist
 402    of two numbers seperated by a hyphen.  Examples:
 403
 404         thread apply 1 2 7 4 backtrace  Apply backtrace cmd to threads 1,2,7,4
 405         thread apply 2-7 9 p foo(1)     Apply p foo(1) cmd to threads 2->7 & 9
 406         thread apply all p x/i $pc      Apply x/i $pc cmd to all threads
 407 */
 408
 409 static void
 410 thread_apply_all_command (cmd, from_tty)
 411      char *cmd;
 412      int from_tty;
 413 {
 414   struct thread_info *tp;
 415   struct cleanup *old_chain;
 416
 417   if (cmd == NULL || *cmd == '\000')
 418     error ("Please specify a command following the thread ID list");
 419
 420   old_chain = make_cleanup (restore_current_thread, inferior_pid);
 421
 422   for (tp = thread_list; tp; tp = tp->next)
 423     if (thread_alive (tp))
 424       {
 425         switch_to_thread (tp->pid);
 426         printf_filtered ("\nThread %d (%s):\n", tp->num,
 427                          target_pid_to_str (inferior_pid));
 428         execute_command (cmd, from_tty);
 429       }
 430 }
 431
 432 static void
 433 thread_apply_command (tidlist, from_tty)
 434      char *tidlist;
 435      int from_tty;
 436 {
 437   char *cmd;
 438   char *p;
 439   struct cleanup *old_chain;
 440
 441   if (tidlist == NULL || *tidlist == '\000')
 442     error ("Please specify a thread ID list");
 443
 444   for (cmd = tidlist; *cmd != '\000' && !isalpha(*cmd); cmd++);
 445
 446   if (*cmd == '\000')
 447     error ("Please specify a command following the thread ID list");
 448
 449   old_chain = make_cleanup (restore_current_thread, inferior_pid);
 450
 451   while (tidlist < cmd)
 452     {
 453       struct thread_info *tp;
 454       int start, end;
 455
 456       start = strtol (tidlist, &p, 10);
 457       if (p == tidlist)
 458         error ("Error parsing %s", tidlist);
 459       tidlist = p;
 460
 461       while (*tidlist == ' ' || *tidlist == '\t')
 462         tidlist++;
 463
 464       if (*tidlist == '-')      /* Got a range of IDs? */
 465         {
 466           tidlist++;    /* Skip the - */
 467           end = strtol (tidlist, &p, 10);
 468           if (p == tidlist)
 469             error ("Error parsing %s", tidlist);
 470           tidlist = p;
 471
 472           while (*tidlist == ' ' || *tidlist == '\t')
 473             tidlist++;
 474         }
 475       else
 476         end = start;
 477
 478       for (; start <= end; start++)
 479         {
 480           tp = find_thread_id (start);
 481
 482           if (!tp)
 483             warning ("Unknown thread %d.", start);
 484           else if (!thread_alive (tp))
 485             warning ("Thread %d has terminated.", start);
 486           else
 487             {
 488               switch_to_thread (tp->pid);
 489               printf_filtered ("\nThread %d (%s):\n", tp->num,
 490                                target_pid_to_str (inferior_pid));
 491               execute_command (cmd, from_tty);
 492             }
 493         }
 494     }
 495 }
 496
 497 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
 498    if prefix of arg is `apply'.  */
 499
 500 static void
 501 thread_command (tidstr, from_tty)
 502      char *tidstr;
 503      int from_tty;
 504 {
 505   int num;
 506   struct thread_info *tp;
 507
 508   if (!tidstr)
 509     error ("Please specify a thread ID.  Use the \"info threads\" command to\n\
 510 see the IDs of currently known threads.");
 511
 512   num = atoi (tidstr);
 513
 514   tp = find_thread_id (num);
 515
 516   if (!tp)
 517     error ("Thread ID %d not known.  Use the \"info threads\" command to\n\
 518 see the IDs of currently known threads.", num);
 519
 520   if (!thread_alive (tp))
 521     error ("Thread ID %d has terminated.\n", num);
 522
 523   switch_to_thread (tp->pid);
 524   if (context_hook)
 525     context_hook (num);
 526   printf_filtered ("[Switching to %s]\n", target_pid_to_str (inferior_pid));
 527   print_stack_frame (selected_frame, selected_frame_level, 1);
 528 }
 529
 530 /* Commands with a prefix of `thread'.  */
 531 struct cmd_list_element *thread_cmd_list = NULL;
 532
 533 void
 534 _initialize_thread ()
 535 {
 536   static struct cmd_list_element *thread_apply_list = NULL;
 537   extern struct cmd_list_element *cmdlist;
 538
 539   add_info ("threads", info_threads_command,
 540             "IDs of currently known threads.");
 541
 542   add_prefix_cmd ("thread", class_run, thread_command,
 543                   "Use this command to switch between threads.\n\
 544 The new thread ID must be currently known.", &thread_cmd_list, "thread ", 1,
 545                   &cmdlist);
 546
 547   add_prefix_cmd ("apply", class_run, thread_apply_command,
 548                   "Apply a command to a list of threads.",
 549                   &thread_apply_list, "apply ", 1, &thread_cmd_list);
 550
 551   add_cmd ("all", class_run, thread_apply_all_command,
 552            "Apply a command to all threads.",
 553            &thread_apply_list);
 554
 555   add_com_alias ("t", "thread", class_run, 1);
 556 }