nojobs.c

   1 /* nojobs.c - functions that make children, remember them, and handle their termination. */
   2
   3 /* This file works under BSD, System V, minix, and Posix systems.  It does
   4    not implement job control. */
   5
   6 /* Copyright (C) 1987-2011 Free Software Foundation, Inc.
   7
   8    This file is part of GNU Bash, the Bourne Again SHell.
   9
  10    Bash is free software: you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation, either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    Bash is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "config.h"
  25
  26 #include "bashtypes.h"
  27 #include "filecntl.h"
  28
  29 #if defined (HAVE_UNISTD_H)
  30 #  include <unistd.h>
  31 #endif
  32
  33 #include <stdio.h>
  34 #include <signal.h>
  35 #include <errno.h>
  36
  37 #if defined (BUFFERED_INPUT)
  38 #  include "input.h"
  39 #endif
  40
  41 /* Need to include this up here for *_TTY_DRIVER definitions. */
  42 #include "shtty.h"
  43
  44 #include "bashintl.h"
  45
  46 #include "shell.h"
  47 #include "jobs.h"
  48 #include "execute_cmd.h"
  49
  50 #include "builtins/builtext.h"  /* for wait_builtin */
  51
  52 #define DEFAULT_CHILD_MAX 32
  53
  54 #if defined (_POSIX_VERSION) || !defined (HAVE_KILLPG)
  55 #  define killpg(pg, sig)               kill(-(pg),(sig))
  56 #endif /* USG || _POSIX_VERSION */
  57
  58 #if !defined (HAVE_SIGINTERRUPT) && !defined (HAVE_POSIX_SIGNALS)
  59 #  define siginterrupt(sig, code)
  60 #endif /* !HAVE_SIGINTERRUPT && !HAVE_POSIX_SIGNALS */
  61
  62 #if defined (HAVE_WAITPID)
  63 #  define WAITPID(pid, statusp, options) waitpid (pid, statusp, options)
  64 #else
  65 #  define WAITPID(pid, statusp, options) wait (statusp)
  66 #endif /* !HAVE_WAITPID */
  67
  68 /* Return the fd from which we are actually getting input. */
  69 #define input_tty() (shell_tty != -1) ? shell_tty : fileno (stderr)
  70
  71 #if !defined (errno)
  72 extern int errno;
  73 #endif /* !errno */
  74
  75 extern int interactive, interactive_shell, login_shell;
  76 extern int subshell_environment;
  77 extern int last_command_exit_value, last_command_exit_signal;
  78 extern int interrupt_immediately;
  79 extern sh_builtin_func_t *this_shell_builtin;
  80 #if defined (HAVE_POSIX_SIGNALS)
  81 extern sigset_t top_level_mask;
  82 #endif
  83 extern procenv_t wait_intr_buf;
  84 extern int wait_signal_received;
  85
  86 volatile pid_t last_made_pid = NO_PID;
  87 volatile pid_t last_asynchronous_pid = NO_PID;
  88
  89 static int queue_sigchld, waiting_for_child;    /* dummy declarations */
  90
  91 /* Call this when you start making children. */
  92 int already_making_children = 0;
  93
  94 /* The controlling tty for this shell. */
  95 int shell_tty = -1;
  96
  97 /* If this is non-zero, $LINES and $COLUMNS are reset after every process
  98    exits from get_tty_state(). */
  99 int check_window_size = CHECKWINSIZE_DEFAULT;
 100
 101 /* We don't have job control. */
 102 int job_control = 0;
 103
 104 int running_in_background = 0;  /* can't tell without job control */
 105
 106 /* STATUS and FLAGS are only valid if pid != NO_PID
 107    STATUS is only valid if (flags & PROC_RUNNING) == 0 */
 108 struct proc_status {
 109   pid_t pid;
 110   int status;   /* Exit status of PID or 128 + fatal signal number */
 111   int flags;
 112 };
 113
 114 /* Values for proc_status.flags */
 115 #define PROC_RUNNING    0x01
 116 #define PROC_NOTIFIED   0x02
 117 #define PROC_ASYNC      0x04
 118 #define PROC_SIGNALED   0x10
 119
 120 /* Return values from find_status_by_pid */
 121 #define PROC_BAD         -1
 122 #define PROC_STILL_ALIVE -2
 123
 124 static struct proc_status *pid_list = (struct proc_status *)NULL;
 125 static int pid_list_size;
 126 static int wait_sigint_received;
 127
 128 static long child_max = -1L;
 129
 130 static void alloc_pid_list __P((void));
 131 static int find_proc_slot __P((pid_t));
 132 static int find_index_by_pid __P((pid_t));
 133 static int find_status_by_pid __P((pid_t));
 134 static int process_exit_status __P((WAIT));
 135 static int find_termsig_by_pid __P((pid_t));
 136 static int get_termsig __P((WAIT));
 137 static void set_pid_status __P((pid_t, WAIT));
 138 static void set_pid_flags __P((pid_t, int));
 139 static void unset_pid_flags __P((pid_t, int));
 140 static int get_pid_flags __P((pid_t));
 141 static void add_pid __P((pid_t, int));
 142 static void mark_dead_jobs_as_notified __P((int));
 143
 144 static sighandler wait_sigint_handler __P((int));
 145 static char *j_strsignal __P((int));
 146
 147 #if defined (HAVE_WAITPID)
 148 static void reap_zombie_children __P((void));
 149 #endif
 150
 151 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 152 static int siginterrupt __P((int, int));
 153 #endif
 154
 155 static void restore_sigint_handler __P((void));
 156
 157 /* Allocate new, or grow existing PID_LIST. */
 158 static void
 159 alloc_pid_list ()
 160 {
 161   register int i;
 162   int old = pid_list_size;
 163
 164   pid_list_size += 10;
 165   pid_list = (struct proc_status *)xrealloc (pid_list, pid_list_size * sizeof (struct proc_status));
 166
 167   /* None of the newly allocated slots have process id's yet. */
 168   for (i = old; i < pid_list_size; i++)
 169     pid_list[i].pid = NO_PID;
 170 }
 171
 172 /* Return the offset within the PID_LIST array of an empty slot.  This can
 173    create new slots if all of the existing slots are taken. */
 174 static int
 175 find_proc_slot (pid)
 176      pid_t pid;
 177 {
 178   register int i;
 179
 180   for (i = 0; i < pid_list_size; i++)
 181     if (pid_list[i].pid == NO_PID || pid_list[i].pid == pid)
 182       return (i);
 183
 184   if (i == pid_list_size)
 185     alloc_pid_list ();
 186
 187   return (i);
 188 }
 189
 190 /* Return the offset within the PID_LIST array of a slot containing PID,
 191    or the value NO_PID if the pid wasn't found. */
 192 static int
 193 find_index_by_pid (pid)
 194      pid_t pid;
 195 {
 196   register int i;
 197
 198   for (i = 0; i < pid_list_size; i++)
 199     if (pid_list[i].pid == pid)
 200       return (i);
 201
 202   return (NO_PID);
 203 }
 204
 205 /* Return the status of PID as looked up in the PID_LIST array.  A
 206    return value of PROC_BAD indicates that PID wasn't found. */
 207 static int
 208 find_status_by_pid (pid)
 209      pid_t pid;
 210 {
 211   int i;
 212
 213   i = find_index_by_pid (pid);
 214   if (i == NO_PID)
 215     return (PROC_BAD);
 216   if (pid_list[i].flags & PROC_RUNNING)
 217     return (PROC_STILL_ALIVE);
 218   return (pid_list[i].status);
 219 }
 220
 221 static int
 222 process_exit_status (status)
 223      WAIT status;
 224 {
 225   if (WIFSIGNALED (status))
 226     return (128 + WTERMSIG (status));
 227   else
 228     return (WEXITSTATUS (status));
 229 }
 230
 231 /* Return the status of PID as looked up in the PID_LIST array.  A
 232    return value of PROC_BAD indicates that PID wasn't found. */
 233 static int
 234 find_termsig_by_pid (pid)
 235      pid_t pid;
 236 {
 237   int i;
 238
 239   i = find_index_by_pid (pid);
 240   if (i == NO_PID)
 241     return (0);
 242   if (pid_list[i].flags & PROC_RUNNING)
 243     return (0);
 244   return (get_termsig ((WAIT)pid_list[i].status));
 245 }
 246
 247 /* Set LAST_COMMAND_EXIT_SIGNAL depending on STATUS.  If STATUS is -1, look
 248    up PID in the pid array and set LAST_COMMAND_EXIT_SIGNAL appropriately
 249    depending on its flags and exit status. */
 250 static int
 251 get_termsig (status)
 252      WAIT status;
 253 {
 254   if (WIFSTOPPED (status) == 0 && WIFSIGNALED (status))
 255     return (WTERMSIG (status));
 256   else
 257     return (0);
 258 }
 259
 260 /* Give PID the status value STATUS in the PID_LIST array. */
 261 static void
 262 set_pid_status (pid, status)
 263      pid_t pid;
 264      WAIT status;
 265 {
 266   int slot;
 267
 268 #if defined (COPROCESS_SUPPORT)
 269   coproc_pidchk (pid, status);
 270 #endif
 271
 272   slot = find_index_by_pid (pid);
 273   if (slot == NO_PID)
 274     return;
 275
 276   pid_list[slot].status = process_exit_status (status);
 277   pid_list[slot].flags &= ~PROC_RUNNING;
 278   if (WIFSIGNALED (status))
 279     pid_list[slot].flags |= PROC_SIGNALED;
 280   /* If it's not a background process, mark it as notified so it gets
 281      cleaned up. */
 282   if ((pid_list[slot].flags & PROC_ASYNC) == 0)
 283     pid_list[slot].flags |= PROC_NOTIFIED;
 284 }
 285
 286 /* Give PID the flags FLAGS in the PID_LIST array. */
 287 static void
 288 set_pid_flags (pid, flags)
 289      pid_t pid;
 290      int flags;
 291 {
 292   int slot;
 293
 294   slot = find_index_by_pid (pid);
 295   if (slot == NO_PID)
 296     return;
 297
 298   pid_list[slot].flags |= flags;
 299 }
 300
 301 /* Unset FLAGS for PID in the pid list */
 302 static void
 303 unset_pid_flags (pid, flags)
 304      pid_t pid;
 305      int flags;
 306 {
 307   int slot;
 308
 309   slot = find_index_by_pid (pid);
 310   if (slot == NO_PID)
 311     return;
 312
 313   pid_list[slot].flags &= ~flags;
 314 }
 315
 316 /* Return the flags corresponding to PID in the PID_LIST array. */
 317 static int
 318 get_pid_flags (pid)
 319      pid_t pid;
 320 {
 321   int slot;
 322
 323   slot = find_index_by_pid (pid);
 324   if (slot == NO_PID)
 325     return 0;
 326
 327   return (pid_list[slot].flags);
 328 }
 329
 330 static void
 331 add_pid (pid, async)
 332      pid_t pid;
 333      int async;
 334 {
 335   int slot;
 336
 337   slot = find_proc_slot (pid);
 338
 339   pid_list[slot].pid = pid;
 340   pid_list[slot].status = -1;
 341   pid_list[slot].flags = PROC_RUNNING;
 342   if (async)
 343     pid_list[slot].flags |= PROC_ASYNC;
 344 }
 345
 346 static void
 347 mark_dead_jobs_as_notified (force)
 348      int force;
 349 {
 350   register int i, ndead;
 351
 352   /* first, count the number of non-running async jobs if FORCE == 0 */
 353   for (i = ndead = 0; force == 0 && i < pid_list_size; i++)
 354     {
 355       if (pid_list[i].pid == NO_PID)
 356         continue;
 357       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 358            (pid_list[i].flags & PROC_ASYNC))
 359         ndead++;
 360     }
 361
 362   if (child_max < 0)
 363     child_max = getmaxchild ();
 364   if (child_max < 0)
 365     child_max = DEFAULT_CHILD_MAX;
 366
 367   if (force == 0 && ndead <= child_max)
 368     return;
 369
 370   /* If FORCE == 0, we just mark as many non-running async jobs as notified
 371      to bring us under the CHILD_MAX limit. */
 372   for (i = 0; i < pid_list_size; i++)
 373     {
 374       if (pid_list[i].pid == NO_PID)
 375         continue;
 376       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 377            pid_list[i].pid != last_asynchronous_pid)
 378         {
 379           pid_list[i].flags |= PROC_NOTIFIED;
 380           if (force == 0 && (pid_list[i].flags & PROC_ASYNC) && --ndead <= child_max)
 381             break;
 382         }
 383     }
 384 }
 385
 386 /* Remove all dead, notified jobs from the pid_list. */
 387 int
 388 cleanup_dead_jobs ()
 389 {
 390   register int i;
 391
 392 #if defined (HAVE_WAITPID)
 393   reap_zombie_children ();
 394 #endif
 395
 396   for (i = 0; i < pid_list_size; i++)
 397     {
 398       if ((pid_list[i].flags & PROC_RUNNING) == 0 &&
 399           (pid_list[i].flags & PROC_NOTIFIED))
 400         pid_list[i].pid = NO_PID;
 401     }
 402
 403 #if defined (COPROCESS_SUPPORT)
 404   coproc_reap ();
 405 #endif
 406
 407   return 0;
 408 }
 409
 410 void
 411 reap_dead_jobs ()
 412 {
 413   mark_dead_jobs_as_notified (0);
 414   cleanup_dead_jobs ();
 415 }
 416
 417 /* Initialize the job control mechanism, and set up the tty stuff. */
 418 initialize_job_control (force)
 419      int force;
 420 {
 421   shell_tty = fileno (stderr);
 422
 423   if (interactive)
 424     get_tty_state ();
 425 }
 426
 427 /* Setup this shell to handle C-C, etc. */
 428 void
 429 initialize_job_signals ()
 430 {
 431   set_signal_handler (SIGINT, sigint_sighandler);
 432
 433   /* If this is a login shell we don't wish to be disturbed by
 434      stop signals. */
 435   if (login_shell)
 436     ignore_tty_job_signals ();
 437 }
 438
 439 #if defined (HAVE_WAITPID)
 440 /* Collect the status of all zombie children so that their system
 441    resources can be deallocated. */
 442 static void
 443 reap_zombie_children ()
 444 {
 445 #  if defined (WNOHANG)
 446   pid_t pid;
 447   WAIT status;
 448
 449   CHECK_TERMSIG;
 450   CHECK_WAIT_INTR;
 451   while ((pid = waitpid (-1, (int *)&status, WNOHANG)) > 0)
 452     set_pid_status (pid, status);
 453 #  endif /* WNOHANG */
 454   CHECK_TERMSIG;
 455   CHECK_WAIT_INTR;
 456 }
 457 #endif /* WAITPID */
 458
 459 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 460
 461 #if !defined (SA_RESTART)
 462 #  define SA_RESTART 0
 463 #endif
 464
 465 static int
 466 siginterrupt (sig, flag)
 467      int sig, flag;
 468 {
 469   struct sigaction act;
 470
 471   sigaction (sig, (struct sigaction *)NULL, &act);
 472
 473   if (flag)
 474     act.sa_flags &= ~SA_RESTART;
 475   else
 476     act.sa_flags |= SA_RESTART;
 477
 478   return (sigaction (sig, &act, (struct sigaction *)NULL));
 479 }
 480 #endif /* !HAVE_SIGINTERRUPT && HAVE_POSIX_SIGNALS */
 481
 482 /* Fork, handling errors.  Returns the pid of the newly made child, or 0.
 483    COMMAND is just for remembering the name of the command; we don't do
 484    anything else with it.  ASYNC_P says what to do with the tty.  If
 485    non-zero, then don't give it away. */
 486 pid_t
 487 make_child (command, async_p)
 488      char *command;
 489      int async_p;
 490 {
 491   pid_t pid;
 492   int forksleep;
 493
 494   /* Discard saved memory. */
 495   if (command)
 496     free (command);
 497
 498   start_pipeline ();
 499
 500 #if defined (BUFFERED_INPUT)
 501   /* If default_buffered_input is active, we are reading a script.  If
 502      the command is asynchronous, we have already duplicated /dev/null
 503      as fd 0, but have not changed the buffered stream corresponding to
 504      the old fd 0.  We don't want to sync the stream in this case. */
 505   if (default_buffered_input != -1 && (!async_p || default_buffered_input > 0))
 506     sync_buffered_stream (default_buffered_input);
 507 #endif /* BUFFERED_INPUT */
 508
 509   /* XXX - block SIGTERM here and unblock in child after fork resets the
 510      set of pending signals? */
 511   RESET_SIGTERM;
 512
 513   /* Create the child, handle severe errors.  Retry on EAGAIN. */
 514   forksleep = 1;
 515   while ((pid = fork ()) < 0 && errno == EAGAIN && forksleep < FORKSLEEP_MAX)
 516     {
 517       sys_error ("fork: retry");
 518       RESET_SIGTERM;
 519
 520 #if defined (HAVE_WAITPID)
 521       /* Posix systems with a non-blocking waitpid () system call available
 522          get another chance after zombies are reaped. */
 523       reap_zombie_children ();
 524       if (forksleep > 1 && sleep (forksleep) != 0)
 525         break;
 526 #else
 527       if (sleep (forksleep) != 0)
 528         break;
 529 #endif /* HAVE_WAITPID */
 530       forksleep <<= 1;
 531     }
 532
 533   if (pid != 0)
 534     RESET_SIGTERM;
 535
 536   if (pid < 0)
 537     {
 538       sys_error ("fork");
 539       last_command_exit_value = EX_NOEXEC;
 540       throw_to_top_level ();
 541     }
 542
 543   if (pid == 0)
 544     {
 545 #if defined (BUFFERED_INPUT)
 546       unset_bash_input (0);
 547 #endif /* BUFFERED_INPUT */
 548
 549 #if defined (HAVE_POSIX_SIGNALS)
 550       /* Restore top-level signal mask. */
 551       sigprocmask (SIG_SETMASK, &top_level_mask, (sigset_t *)NULL);
 552 #endif
 553
 554 #if 0
 555       /* Ignore INT and QUIT in asynchronous children. */
 556       if (async_p)
 557         last_asynchronous_pid = getpid ();
 558 #endif
 559
 560       default_tty_job_signals ();
 561     }
 562   else
 563     {
 564       /* In the parent. */
 565
 566       last_made_pid = pid;
 567
 568       if (async_p)
 569         last_asynchronous_pid = pid;
 570
 571       add_pid (pid, async_p);
 572     }
 573   return (pid);
 574 }
 575
 576 void
 577 ignore_tty_job_signals ()
 578 {
 579 #if defined (SIGTSTP)
 580   set_signal_handler (SIGTSTP, SIG_IGN);
 581   set_signal_handler (SIGTTIN, SIG_IGN);
 582   set_signal_handler (SIGTTOU, SIG_IGN);
 583 #endif
 584 }
 585
 586 void
 587 default_tty_job_signals ()
 588 {
 589 #if defined (SIGTSTP)
 590   if (signal_is_trapped (SIGTSTP) == 0 && signal_is_hard_ignored (SIGTSTP))
 591     set_signal_handler (SIGTSTP, SIG_IGN);
 592   else
 593     set_signal_handler (SIGTSTP, SIG_DFL);
 594   if (signal_is_trapped (SIGTTIN) == 0 && signal_is_hard_ignored (SIGTTIN))
 595     set_signal_handler (SIGTTIN, SIG_IGN);
 596   else
 597     set_signal_handler (SIGTTIN, SIG_DFL);
 598   if (signal_is_trapped (SIGTTOU) == 0 && signal_is_hard_ignored (SIGTTOU))
 599     set_signal_handler (SIGTTOU, SIG_IGN);
 600   else
 601     set_signal_handler (SIGTTOU, SIG_DFL);
 602 #endif
 603 }
 604
 605 /* Called once in a parent process. */
 606 void
 607 get_original_tty_job_signals ()
 608 {
 609   static int fetched = 0;
 610
 611   if (fetched == 0)
 612     {
 613 #if defined (SIGTSTP)
 614       get_original_signal (SIGTSTP);
 615       get_original_signal (SIGTTIN);
 616       get_original_signal (SIGTTOU);
 617 #endif
 618       fetched = 1;
 619     }
 620 }
 621
 622 /* Wait for a single pid (PID) and return its exit status.  Called by
 623    the wait builtin. */
 624 int
 625 wait_for_single_pid (pid)
 626      pid_t pid;
 627 {
 628   pid_t got_pid;
 629   WAIT status;
 630   int pstatus, flags;
 631
 632   pstatus = find_status_by_pid (pid);
 633
 634   if (pstatus == PROC_BAD)
 635     {
 636       internal_error (_("wait: pid %ld is not a child of this shell"), (long)pid);
 637       return (127);
 638     }
 639
 640   if (pstatus != PROC_STILL_ALIVE)
 641     {
 642       if (pstatus > 128)
 643         last_command_exit_signal = find_termsig_by_pid (pid);
 644       return (pstatus);
 645     }
 646
 647   siginterrupt (SIGINT, 1);
 648   while ((got_pid = WAITPID (pid, &status, 0)) != pid)
 649     {
 650       CHECK_TERMSIG;
 651       CHECK_WAIT_INTR;
 652       if (got_pid < 0)
 653         {
 654           if (errno != EINTR && errno != ECHILD)
 655             {
 656               siginterrupt (SIGINT, 0);
 657               sys_error ("wait");
 658             }
 659           break;
 660         }
 661       else if (got_pid > 0)
 662         set_pid_status (got_pid, status);
 663     }
 664
 665   if (got_pid > 0)
 666     {
 667       set_pid_status (got_pid, status);
 668       set_pid_flags (got_pid, PROC_NOTIFIED);
 669     }
 670
 671   siginterrupt (SIGINT, 0);
 672   QUIT;
 673
 674   return (got_pid > 0 ? process_exit_status (status) : -1);
 675 }
 676
 677 /* Wait for all of the shell's children to exit.  Called by the `wait'
 678    builtin. */
 679 void
 680 wait_for_background_pids ()
 681 {
 682   pid_t got_pid;
 683   WAIT status;
 684
 685   /* If we aren't using job control, we let the kernel take care of the
 686      bookkeeping for us.  wait () will return -1 and set errno to ECHILD
 687      when there are no more unwaited-for child processes on both
 688      4.2 BSD-based and System V-based systems. */
 689
 690   siginterrupt (SIGINT, 1);
 691
 692   /* Wait for ECHILD */
 693   while ((got_pid = WAITPID (-1, &status, 0)) != -1)
 694     set_pid_status (got_pid, status);
 695
 696   if (errno != EINTR && errno != ECHILD)
 697     {
 698       siginterrupt (SIGINT, 0);
 699       sys_error("wait");
 700     }
 701
 702   siginterrupt (SIGINT, 0);
 703   QUIT;
 704
 705   mark_dead_jobs_as_notified (1);
 706   cleanup_dead_jobs ();
 707 }
 708
 709 void
 710 wait_sigint_cleanup ()
 711 {
 712 }
 713
 714 /* Make OLD_SIGINT_HANDLER the SIGINT signal handler. */
 715 #define INVALID_SIGNAL_HANDLER (SigHandler *)wait_for_background_pids
 716 static SigHandler *old_sigint_handler = INVALID_SIGNAL_HANDLER;
 717
 718 static void
 719 restore_sigint_handler ()
 720 {
 721   if (old_sigint_handler != INVALID_SIGNAL_HANDLER)
 722     {
 723       set_signal_handler (SIGINT, old_sigint_handler);
 724       old_sigint_handler = INVALID_SIGNAL_HANDLER;
 725     }
 726 }
 727
 728 /* Handle SIGINT while we are waiting for children in a script to exit.
 729    All interrupts are effectively ignored by the shell, but allowed to
 730    kill a running job. */
 731 static sighandler
 732 wait_sigint_handler (sig)
 733      int sig;
 734 {
 735   SigHandler *sigint_handler;
 736
 737   /* If we got a SIGINT while in `wait', and SIGINT is trapped, do
 738      what POSIX.2 says (see builtins/wait.def for more info). */
 739   if (this_shell_builtin && this_shell_builtin == wait_builtin &&
 740       signal_is_trapped (SIGINT) &&
 741       ((sigint_handler = trap_to_sighandler (SIGINT)) == trap_handler))
 742     {
 743       last_command_exit_value = 128+SIGINT;
 744       restore_sigint_handler ();
 745       interrupt_immediately = 0;
 746       trap_handler (SIGINT);    /* set pending_traps[SIGINT] */
 747       wait_signal_received = SIGINT;
 748       SIGRETURN (0);
 749     }
 750
 751   if (interrupt_immediately)
 752     {
 753       last_command_exit_value = EXECUTION_FAILURE;
 754       restore_sigint_handler ();
 755       ADDINTERRUPT;
 756       QUIT;
 757     }
 758
 759   wait_sigint_received = 1;
 760
 761   SIGRETURN (0);
 762 }
 763
 764 static char *
 765 j_strsignal (s)
 766      int s;
 767 {
 768   static char retcode_name_buffer[64] = { '\0' };
 769   char *x;
 770
 771   x = strsignal (s);
 772   if (x == 0)
 773     {
 774       x = retcode_name_buffer;
 775       sprintf (x, "Signal %d", s);
 776     }
 777   return x;
 778 }
 779
 780 /* Wait for pid (one of our children) to terminate.  This is called only
 781    by the execution code in execute_cmd.c. */
 782 int
 783 wait_for (pid)
 784      pid_t pid;
 785 {
 786   int return_val, pstatus;
 787   pid_t got_pid;
 788   WAIT status;
 789
 790   pstatus = find_status_by_pid (pid);
 791
 792   if (pstatus == PROC_BAD)
 793     return (0);
 794
 795   if (pstatus != PROC_STILL_ALIVE)
 796     {
 797       if (pstatus > 128)
 798         last_command_exit_signal = find_termsig_by_pid (pid);
 799       return (pstatus);
 800     }
 801
 802   /* If we are running a script, ignore SIGINT while we're waiting for
 803      a child to exit.  The loop below does some of this, but not all. */
 804   wait_sigint_received = 0;
 805   if (interactive_shell == 0)
 806     old_sigint_handler = set_signal_handler (SIGINT, wait_sigint_handler);
 807
 808   while ((got_pid = WAITPID (-1, &status, 0)) != pid) /* XXX was pid now -1 */
 809     {
 810       CHECK_TERMSIG;
 811       CHECK_WAIT_INTR;
 812       if (got_pid < 0 && errno == ECHILD)
 813         {
 814 #if !defined (_POSIX_VERSION)
 815           status.w_termsig = status.w_retcode = 0;
 816 #else
 817           status = 0;
 818 #endif /* _POSIX_VERSION */
 819           break;
 820         }
 821       else if (got_pid < 0 && errno != EINTR)
 822         programming_error ("wait_for(%ld): %s", (long)pid, strerror(errno));
 823       else if (got_pid > 0)
 824         set_pid_status (got_pid, status);
 825     }
 826
 827   if (got_pid > 0)
 828     set_pid_status (got_pid, status);
 829
 830 #if defined (HAVE_WAITPID)
 831   if (got_pid >= 0)
 832     reap_zombie_children ();
 833 #endif /* HAVE_WAITPID */
 834
 835   CHECK_TERMSIG;
 836   CHECK_WAIT_INTR;
 837
 838   if (interactive_shell == 0)
 839     {
 840       SigHandler *temp_handler;
 841
 842       temp_handler = old_sigint_handler;
 843       restore_sigint_handler ();
 844
 845       /* If the job exited because of SIGINT, make sure the shell acts as if
 846          it had received one also. */
 847       if (WIFSIGNALED (status) && (WTERMSIG (status) == SIGINT))
 848         {
 849
 850           if (maybe_call_trap_handler (SIGINT) == 0)
 851             {
 852               if (temp_handler == SIG_DFL)
 853                 termsig_handler (SIGINT);
 854               else if (temp_handler != INVALID_SIGNAL_HANDLER && temp_handler != SIG_IGN)
 855                 (*temp_handler) (SIGINT);
 856             }
 857         }
 858     }
 859
 860   /* Default return value. */
 861   /* ``a full 8 bits of status is returned'' */
 862   return_val = process_exit_status (status);
 863   last_command_exit_signal = get_termsig (status);
 864
 865 #if defined (DONT_REPORT_SIGPIPE) && defined (DONT_REPORT_SIGTERM)
 866 #  define REPORTSIG(x) ((x) != SIGINT && (x) != SIGPIPE && (x) != SIGTERM)
 867 #elif !defined (DONT_REPORT_SIGPIPE) && !defined (DONT_REPORT_SIGTERM)
 868 #  define REPORTSIG(x) ((x) != SIGINT)
 869 #elif defined (DONT_REPORT_SIGPIPE)
 870 #  define REPORTSIG(x) ((x) != SIGINT && (x) != SIGPIPE)
 871 #else
 872 #  define REPORTSIG(x) ((x) != SIGINT && (x) != SIGTERM)
 873 #endif
 874
 875   if ((WIFSTOPPED (status) == 0) && WIFSIGNALED (status) && REPORTSIG(WTERMSIG (status)))
 876     {
 877       fprintf (stderr, "%s", j_strsignal (WTERMSIG (status)));
 878       if (WIFCORED (status))
 879         fprintf (stderr, _(" (core dumped)"));
 880       fprintf (stderr, "\n");
 881     }
 882
 883   if (interactive_shell && subshell_environment == 0)
 884     {
 885       if (WIFSIGNALED (status) || WIFSTOPPED (status))
 886         set_tty_state ();
 887       else
 888         get_tty_state ();
 889     }
 890   else if (interactive_shell == 0 && subshell_environment == 0 && check_window_size)
 891     get_new_window_size (0, (int *)0, (int *)0);
 892
 893   return (return_val);
 894 }
 895
 896 /* Send PID SIGNAL.  Returns -1 on failure, 0 on success.  If GROUP is non-zero,
 897    or PID is less than -1, then kill the process group associated with PID. */
 898 int
 899 kill_pid (pid, signal, group)
 900      pid_t pid;
 901      int signal, group;
 902 {
 903   int result;
 904
 905   if (pid < -1)
 906     {
 907       pid = -pid;
 908       group = 1;
 909     }
 910   result = group ? killpg (pid, signal) : kill (pid, signal);
 911   return (result);
 912 }
 913
 914 static TTYSTRUCT shell_tty_info;
 915 static int got_tty_state;
 916
 917 /* Fill the contents of shell_tty_info with the current tty info. */
 918 get_tty_state ()
 919 {
 920   int tty;
 921
 922   tty = input_tty ();
 923   if (tty != -1)
 924     {
 925       ttgetattr (tty, &shell_tty_info);
 926       got_tty_state = 1;
 927       if (check_window_size)
 928         get_new_window_size (0, (int *)0, (int *)0);
 929     }
 930 }
 931
 932 /* Make the current tty use the state in shell_tty_info. */
 933 int
 934 set_tty_state ()
 935 {
 936   int tty;
 937
 938   tty = input_tty ();
 939   if (tty != -1)
 940     {
 941       if (got_tty_state == 0)
 942         return 0;
 943       ttsetattr (tty, &shell_tty_info);
 944     }
 945   return 0;
 946 }
 947
 948 /* Give the terminal to PGRP.  */
 949 give_terminal_to (pgrp, force)
 950      pid_t pgrp;
 951      int force;
 952 {
 953 }
 954
 955 /* Stop a pipeline. */
 956 int
 957 stop_pipeline (async, ignore)
 958      int async;
 959      COMMAND *ignore;
 960 {
 961   already_making_children = 0;
 962   return 0;
 963 }
 964
 965 void
 966 start_pipeline ()
 967 {
 968   already_making_children = 1;
 969 }
 970
 971 void
 972 stop_making_children ()
 973 {
 974   already_making_children = 0;
 975 }
 976
 977 int
 978 get_job_by_pid (pid, block)
 979      pid_t pid;
 980      int block;
 981 {
 982   int i;
 983
 984   i = find_index_by_pid (pid);
 985   return ((i == NO_PID) ? PROC_BAD : i);
 986 }
 987
 988 /* Print descriptive information about the job with leader pid PID. */
 989 void
 990 describe_pid (pid)
 991      pid_t pid;
 992 {
 993   fprintf (stderr, "%ld\n", (long) pid);
 994 }
 995
 996 int
 997 freeze_jobs_list ()
 998 {
 999 }
1000
1001 void
1002 unfreeze_jobs_list ()
1003 {
1004 }
1005
1006 int
1007 count_all_jobs ()
1008 {
1009   return 0;
1010 }