gdb/thread.c

   1 /* Multi-process/thread control for GDB, the GNU debugger.
   2    Copyright 1986, 1987, 1988, 1993
   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 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 static struct thread_info *
 129 find_thread_id (num)
 130     int num;
 131 {
 132   struct thread_info *tp;
 133
 134   for (tp = thread_list; tp; tp = tp->next)
 135     if (tp->num == num)
 136       return tp;
 137
 138   return NULL;
 139 }
 140
 141 int
 142 valid_thread_id (num)
 143     int num;
 144 {
 145   struct thread_info *tp;
 146
 147   for (tp = thread_list; tp; tp = tp->next)
 148     if (tp->num == num)
 149       return 1;
 150
 151   return 0;
 152 }
 153
 154 int
 155 pid_to_thread_id (pid)
 156     int pid;
 157 {
 158   struct thread_info *tp;
 159
 160   for (tp = thread_list; tp; tp = tp->next)
 161     if (tp->pid == pid)
 162       return tp->num;
 163
 164   return 0;
 165 }
 166
 167 int
 168 thread_id_to_pid (num)
 169     int num;
 170 {
 171   struct thread_info *thread = find_thread_id (num);
 172   if (thread)
 173     return thread->pid;
 174   else
 175     return -1;
 176 }
 177
 178 int
 179 in_thread_list (pid)
 180     int pid;
 181 {
 182   struct thread_info *tp;
 183
 184   for (tp = thread_list; tp; tp = tp->next)
 185     if (tp->pid == pid)
 186       return 1;
 187
 188   return 0;                     /* Never heard of 'im */
 189 }
 190
 191 /* Load infrun state for the thread PID.  */
 192
 193 void load_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 194                         trap_expected, step_resume_breakpoint,
 195                         through_sigtramp_breakpoint, step_range_start,
 196                         step_range_end, step_frame_address,
 197                         handling_longjmp, another_trap)
 198      int pid;
 199      CORE_ADDR *prev_pc;
 200      CORE_ADDR *prev_func_start;
 201      char **prev_func_name;
 202      int *trap_expected;
 203      struct breakpoint **step_resume_breakpoint;
 204      struct breakpoint **through_sigtramp_breakpoint;
 205      CORE_ADDR *step_range_start;
 206      CORE_ADDR *step_range_end;
 207      CORE_ADDR *step_frame_address;
 208      int *handling_longjmp;
 209      int *another_trap;
 210 {
 211   struct thread_info *tp;
 212
 213   /* If we can't find the thread, then we're debugging a single threaded
 214      process.  No need to do anything in that case.  */
 215   tp = find_thread_id (pid_to_thread_id (pid));
 216   if (tp == NULL)
 217     return;
 218
 219   *prev_pc = tp->prev_pc;
 220   *prev_func_start = tp->prev_func_start;
 221   *prev_func_name = tp->prev_func_name;
 222   *step_resume_breakpoint = tp->step_resume_breakpoint;
 223   *step_range_start = tp->step_range_start;
 224   *step_range_end = tp->step_range_end;
 225   *step_frame_address = tp->step_frame_address;
 226   *through_sigtramp_breakpoint = tp->through_sigtramp_breakpoint;
 227   *handling_longjmp = tp->handling_longjmp;
 228   *trap_expected = tp->trap_expected;
 229   *another_trap = tp->another_trap;
 230 }
 231
 232 /* Save infrun state for the thread PID.  */
 233
 234 void save_infrun_state (pid, prev_pc, prev_func_start, prev_func_name,
 235                         trap_expected, step_resume_breakpoint,
 236                         through_sigtramp_breakpoint, step_range_start,
 237                         step_range_end, step_frame_address,
 238                         handling_longjmp, another_trap)
 239      int pid;
 240      CORE_ADDR prev_pc;
 241      CORE_ADDR prev_func_start;
 242      char *prev_func_name;
 243      int trap_expected;
 244      struct breakpoint *step_resume_breakpoint;
 245      struct breakpoint *through_sigtramp_breakpoint;
 246      CORE_ADDR step_range_start;
 247      CORE_ADDR step_range_end;
 248      CORE_ADDR step_frame_address;
 249      int handling_longjmp;
 250      int another_trap;
 251 {
 252   struct thread_info *tp;
 253
 254   /* If we can't find the thread, then we're debugging a single-threaded
 255      process.  Nothing to do in that case.  */
 256   tp = find_thread_id (pid_to_thread_id (pid));
 257   if (tp == NULL)
 258     return;
 259
 260   tp->prev_pc = prev_pc;
 261   tp->prev_func_start = prev_func_start;
 262   tp->prev_func_name = prev_func_name;
 263   tp->step_resume_breakpoint = step_resume_breakpoint;
 264   tp->step_range_start = step_range_start;
 265   tp->step_range_end = step_range_end;
 266   tp->step_frame_address = step_frame_address;
 267   tp->through_sigtramp_breakpoint = through_sigtramp_breakpoint;
 268   tp->handling_longjmp = handling_longjmp;
 269   tp->trap_expected = trap_expected;
 270   tp->another_trap = another_trap;
 271 }
 272
 273 /* Return true if TP is an active thread. */
 274 static int
 275 thread_alive (tp)
 276      struct thread_info *tp;
 277 {
 278   if (tp->pid == -1)
 279     return 0;
 280   if (! target_thread_alive (tp->pid))
 281     {
 282       tp->pid = -1;     /* Mark it as dead */
 283       return 0;
 284     }
 285   return 1;
 286 }
 287
 288 static void
 289 prune_threads ()
 290 {
 291   struct thread_info *tp, *tpprev, *next;
 292
 293   tpprev = 0;
 294   for (tp = thread_list; tp; tp = next)
 295     {
 296       next = tp->next;
 297       if (!thread_alive (tp))
 298         {
 299           if (tpprev)
 300             tpprev->next = next;
 301           else
 302             thread_list  = next;
 303           free (tp);
 304         }
 305       else
 306         tpprev = tp;
 307     }
 308 }
 309
 310 /* Print information about currently known threads */
 311
 312 static void
 313 info_threads_command (arg, from_tty)
 314      char *arg;
 315      int from_tty;
 316 {
 317   struct thread_info *tp;
 318   int current_pid = inferior_pid;
 319
 320   /* Avoid coredumps which would happen if we tried to access a NULL
 321      selected_frame.  */
 322   if (!target_has_stack) error ("No stack.");
 323
 324   prune_threads ();
 325   for (tp = thread_list; tp; tp = tp->next)
 326     {
 327       if (tp->pid == current_pid)
 328         printf_filtered ("* ");
 329       else
 330         printf_filtered ("  ");
 331
 332       printf_filtered ("%d %s  ", tp->num, target_pid_to_str (tp->pid));
 333
 334       switch_to_thread (tp->pid);
 335       print_stack_frame (selected_frame, -1, 0);
 336     }
 337
 338   switch_to_thread (current_pid);
 339 }
 340
 341 /* Switch from one thread to another. */
 342
 343 static void
 344 switch_to_thread (pid)
 345      int pid;
 346 {
 347   if (pid == inferior_pid)
 348     return;
 349
 350   inferior_pid = pid;
 351   flush_cached_frames ();
 352   registers_changed ();
 353   stop_pc = read_pc();
 354   select_frame (get_current_frame (), 0);
 355 }
 356
 357 static void
 358 restore_current_thread (pid)
 359      int pid;
 360 {
 361   if (pid != inferior_pid)
 362     switch_to_thread (pid);
 363 }
 364
 365 /* Apply a GDB command to a list of threads.  List syntax is a whitespace
 366    seperated list of numbers, or ranges, or the keyword `all'.  Ranges consist
 367    of two numbers seperated by a hyphen.  Examples:
 368
 369         thread apply 1 2 7 4 backtrace  Apply backtrace cmd to threads 1,2,7,4
 370         thread apply 2-7 9 p foo(1)     Apply p foo(1) cmd to threads 2->7 & 9
 371         thread apply all p x/i $pc      Apply x/i $pc cmd to all threads
 372 */
 373
 374 static void
 375 thread_apply_all_command (cmd, from_tty)
 376      char *cmd;
 377      int from_tty;
 378 {
 379   struct thread_info *tp;
 380   struct cleanup *old_chain;
 381
 382   if (cmd == NULL || *cmd == '\000')
 383     error ("Please specify a command following the thread ID list");
 384
 385   old_chain = make_cleanup (restore_current_thread, inferior_pid);
 386
 387   for (tp = thread_list; tp; tp = tp->next)
 388     if (thread_alive (tp))
 389       {
 390         switch_to_thread (tp->pid);
 391         printf_filtered ("\nThread %d (%s):\n", tp->num,
 392                          target_pid_to_str (inferior_pid));
 393         execute_command (cmd, from_tty);
 394       }
 395 }
 396
 397 static void
 398 thread_apply_command (tidlist, from_tty)
 399      char *tidlist;
 400      int from_tty;
 401 {
 402   char *cmd;
 403   char *p;
 404   struct cleanup *old_chain;
 405
 406   if (tidlist == NULL || *tidlist == '\000')
 407     error ("Please specify a thread ID list");
 408
 409   for (cmd = tidlist; *cmd != '\000' && !isalpha(*cmd); cmd++);
 410
 411   if (*cmd == '\000')
 412     error ("Please specify a command following the thread ID list");
 413
 414   old_chain = make_cleanup (restore_current_thread, inferior_pid);
 415
 416   while (tidlist < cmd)
 417     {
 418       struct thread_info *tp;
 419       int start, end;
 420
 421       start = strtol (tidlist, &p, 10);
 422       if (p == tidlist)
 423         error ("Error parsing %s", tidlist);
 424       tidlist = p;
 425
 426       while (*tidlist == ' ' || *tidlist == '\t')
 427         tidlist++;
 428
 429       if (*tidlist == '-')      /* Got a range of IDs? */
 430         {
 431           tidlist++;    /* Skip the - */
 432           end = strtol (tidlist, &p, 10);
 433           if (p == tidlist)
 434             error ("Error parsing %s", tidlist);
 435           tidlist = p;
 436
 437           while (*tidlist == ' ' || *tidlist == '\t')
 438             tidlist++;
 439         }
 440       else
 441         end = start;
 442
 443       for (; start <= end; start++)
 444         {
 445           tp = find_thread_id (start);
 446
 447           if (!tp)
 448             warning ("Unknown thread %d.", start);
 449           else if (!thread_alive (tp))
 450             warning ("Thread %d has terminated.", start);
 451           else
 452             {
 453               switch_to_thread (tp->pid);
 454               printf_filtered ("\nThread %d (%s):\n", tp->num,
 455                                target_pid_to_str (inferior_pid));
 456               execute_command (cmd, from_tty);
 457             }
 458         }
 459     }
 460 }
 461
 462 /* Switch to the specified thread.  Will dispatch off to thread_apply_command
 463    if prefix of arg is `apply'.  */
 464
 465 static void
 466 thread_command (tidstr, from_tty)
 467      char *tidstr;
 468      int from_tty;
 469 {
 470   int num;
 471   struct thread_info *tp;
 472
 473   if (!tidstr)
 474     error ("Please specify a thread ID.  Use the \"info threads\" command to\n\
 475 see the IDs of currently known threads.");
 476
 477   num = atoi (tidstr);
 478
 479   tp = find_thread_id (num);
 480
 481   if (!tp)
 482     error ("Thread ID %d not known.  Use the \"info threads\" command to\n\
 483 see the IDs of currently known threads.", num);
 484
 485   if (!thread_alive (tp))
 486     error ("Thread ID %d has terminated.\n", num);
 487
 488   switch_to_thread (tp->pid);
 489
 490   printf_filtered ("[Switching to %s]\n", target_pid_to_str (inferior_pid));
 491   print_stack_frame (selected_frame, selected_frame_level, 1);
 492 }
 493
 494 /* Commands with a prefix of `thread'.  */
 495 struct cmd_list_element *thread_cmd_list = NULL;
 496
 497 void
 498 _initialize_thread ()
 499 {
 500   static struct cmd_list_element *thread_apply_list = NULL;
 501   extern struct cmd_list_element *cmdlist;
 502
 503   add_info ("threads", info_threads_command,
 504             "IDs of currently known threads.");
 505
 506   add_prefix_cmd ("thread", class_run, thread_command,
 507                   "Use this command to switch between threads.\n\
 508 The new thread ID must be currently known.", &thread_cmd_list, "thread ", 1,
 509                   &cmdlist);
 510
 511   add_prefix_cmd ("apply", class_run, thread_apply_command,
 512                   "Apply a command to a list of threads.",
 513                   &thread_apply_list, "apply ", 1, &thread_cmd_list);
 514
 515   add_cmd ("all", class_run, thread_apply_all_command,
 516            "Apply a command to all threads.",
 517            &thread_apply_list);
 518
 519   add_com_alias ("t", "thread", class_run, 1);
 520 }