nojobs.c

   1 /* The thing that makes children, remembers them, and contains wait loops. */
   2
   3 /* This file works under BSD, System V, minix, and Posix systems.  It does
   4    not implement job control. */
   5
   6 /* Copyright (C) 1987-2006 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 it under
  11    the terms of the GNU General Public License as published by the Free
  12    Software Foundation; either version 2, or (at your option) any later
  13    version.
  14
  15    Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  16    WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18    for more details.
  19
  20    You should have received a copy of the GNU General Public License along
  21    with Bash; see the file COPYING.  If not, write to the Free Software
  22    Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA. */
  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
  49 #include "builtins/builtext.h"  /* for wait_builtin */
  50
  51 #define DEFAULT_CHILD_MAX 32
  52
  53 #if defined (_POSIX_VERSION) || !defined (HAVE_KILLPG)
  54 #  define killpg(pg, sig)               kill(-(pg),(sig))
  55 #endif /* USG || _POSIX_VERSION */
  56
  57 #if !defined (HAVE_SIGINTERRUPT) && !defined (HAVE_POSIX_SIGNALS)
  58 #  define siginterrupt(sig, code)
  59 #endif /* !HAVE_SIGINTERRUPT && !HAVE_POSIX_SIGNALS */
  60
  61 #if defined (HAVE_WAITPID)
  62 #  define WAITPID(pid, statusp, options) waitpid (pid, statusp, options)
  63 #else
  64 #  define WAITPID(pid, statusp, options) wait (statusp)
  65 #endif /* !HAVE_WAITPID */
  66
  67 /* Return the fd from which we are actually getting input. */
  68 #define input_tty() (shell_tty != -1) ? shell_tty : fileno (stderr)
  69
  70 #if !defined (errno)
  71 extern int errno;
  72 #endif /* !errno */
  73
  74 extern int interactive, interactive_shell, login_shell;
  75 extern int subshell_environment;
  76 extern int last_command_exit_value, last_command_exit_signal;
  77 extern int interrupt_immediately;
  78 extern sh_builtin_func_t *this_shell_builtin;
  79 #if defined (HAVE_POSIX_SIGNALS)
  80 extern sigset_t top_level_mask;
  81 #endif
  82 extern procenv_t wait_intr_buf;
  83 extern int wait_signal_received;
  84
  85 pid_t last_made_pid = NO_PID;
  86 pid_t last_asynchronous_pid = NO_PID;
  87
  88 /* Call this when you start making children. */
  89 int already_making_children = 0;
  90
  91 /* The controlling tty for this shell. */
  92 int shell_tty = -1;
  93
  94 /* If this is non-zero, $LINES and $COLUMNS are reset after every process
  95    exits from get_tty_state(). */
  96 int check_window_size;
  97
  98 /* STATUS and FLAGS are only valid if pid != NO_PID
  99    STATUS is only valid if (flags & PROC_RUNNING) == 0 */
 100 struct proc_status {
 101   pid_t pid;
 102   int status;   /* Exit status of PID or 128 + fatal signal number */
 103   int flags;
 104 };
 105
 106 /* Values for proc_status.flags */
 107 #define PROC_RUNNING    0x01
 108 #define PROC_NOTIFIED   0x02
 109 #define PROC_ASYNC      0x04
 110 #define PROC_SIGNALED   0x10
 111
 112 /* Return values from find_status_by_pid */
 113 #define PROC_BAD         -1
 114 #define PROC_STILL_ALIVE -2
 115
 116 static struct proc_status *pid_list = (struct proc_status *)NULL;
 117 static int pid_list_size;
 118 static int wait_sigint_received;
 119
 120 static long child_max = -1L;
 121
 122 static void alloc_pid_list __P((void));
 123 static int find_proc_slot __P((void));
 124 static int find_index_by_pid __P((pid_t));
 125 static int find_status_by_pid __P((pid_t));
 126 static int process_exit_status __P((WAIT));
 127 static int find_termsig_by_pid __P((pid_t));
 128 static int get_termsig __P((WAIT));
 129 static void set_pid_status __P((pid_t, WAIT));
 130 static void set_pid_flags __P((pid_t, int));
 131 static void unset_pid_flags __P((pid_t, int));
 132 static int get_pid_flags __P((pid_t));
 133 static void add_pid __P((pid_t, int));
 134 static void mark_dead_jobs_as_notified __P((int));
 135
 136 static sighandler wait_sigint_handler __P((int));
 137 static char *j_strsignal __P((int));
 138
 139 #if defined (HAVE_WAITPID)
 140 static void reap_zombie_children __P((void));
 141 #endif
 142
 143 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 144 static int siginterrupt __P((int, int));
 145 #endif
 146
 147 static void restore_sigint_handler __P((void));
 148
 149 /* Allocate new, or grow existing PID_LIST. */
 150 static void
 151 alloc_pid_list ()
 152 {
 153   register int i;
 154   int old = pid_list_size;
 155
 156   pid_list_size += 10;
 157   pid_list = (struct proc_status *)xrealloc (pid_list, pid_list_size * sizeof (struct proc_status));
 158
 159   /* None of the newly allocated slots have process id's yet. */
 160   for (i = old; i < pid_list_size; i++)
 161     pid_list[i].pid = NO_PID;
 162 }
 163
 164 /* Return the offset within the PID_LIST array of an empty slot.  This can
 165    create new slots if all of the existing slots are taken. */
 166 static int
 167 find_proc_slot ()
 168 {
 169   register int i;
 170
 171   for (i = 0; i < pid_list_size; i++)
 172     if (pid_list[i].pid == NO_PID)
 173       return (i);
 174
 175   if (i == pid_list_size)
 176     alloc_pid_list ();
 177
 178   return (i);
 179 }
 180
 181 /* Return the offset within the PID_LIST array of a slot containing PID,
 182    or the value NO_PID if the pid wasn't found. */
 183 static int
 184 find_index_by_pid (pid)
 185      pid_t pid;
 186 {
 187   register int i;
 188
 189   for (i = 0; i < pid_list_size; i++)
 190     if (pid_list[i].pid == pid)
 191       return (i);
 192
 193   return (NO_PID);
 194 }
 195
 196 /* Return the status of PID as looked up in the PID_LIST array.  A
 197    return value of PROC_BAD indicates that PID wasn't found. */
 198 static int
 199 find_status_by_pid (pid)
 200      pid_t pid;
 201 {
 202   int i;
 203
 204   i = find_index_by_pid (pid);
 205   if (i == NO_PID)
 206     return (PROC_BAD);
 207   if (pid_list[i].flags & PROC_RUNNING)
 208     return (PROC_STILL_ALIVE);
 209   return (pid_list[i].status);
 210 }
 211
 212 static int
 213 process_exit_status (status)
 214      WAIT status;
 215 {
 216   if (WIFSIGNALED (status))
 217     return (128 + WTERMSIG (status));
 218   else
 219     return (WEXITSTATUS (status));
 220 }
 221
 222 /* Return the status of PID as looked up in the PID_LIST array.  A
 223    return value of PROC_BAD indicates that PID wasn't found. */
 224 static int
 225 find_termsig_by_pid (pid)
 226      pid_t pid;
 227 {
 228   int i;
 229
 230   i = find_index_by_pid (pid);
 231   if (i == NO_PID)
 232     return (0);
 233   if (pid_list[i].flags & PROC_RUNNING)
 234     return (0);
 235   return (get_termsig (pid_list[i].status));
 236 }
 237
 238 /* Set LAST_COMMAND_EXIT_SIGNAL depending on STATUS.  If STATUS is -1, look
 239    up PID in the pid array and set LAST_COMMAND_EXIT_SIGNAL appropriately
 240    depending on its flags and exit status. */
 241 static int
 242 get_termsig (status)
 243      WAIT status;
 244 {
 245   if (WIFSTOPPED (status) == 0 && WIFSIGNALED (status))
 246     return (WTERMSIG (status));
 247   else
 248     return (0);
 249 }
 250
 251 /* Give PID the status value STATUS in the PID_LIST array. */
 252 static void
 253 set_pid_status (pid, status)
 254      pid_t pid;
 255      WAIT status;
 256 {
 257   int slot;
 258
 259   slot = find_index_by_pid (pid);
 260   if (slot == NO_PID)
 261     return;
 262
 263   pid_list[slot].status = process_exit_status (status);
 264   pid_list[slot].flags &= ~PROC_RUNNING;
 265   if (WIFSIGNALED (status))
 266     pid_list[slot].flags |= PROC_SIGNALED;
 267   /* If it's not a background process, mark it as notified so it gets
 268      cleaned up. */
 269   if ((pid_list[slot].flags & PROC_ASYNC) == 0)
 270     pid_list[slot].flags |= PROC_NOTIFIED;
 271 }
 272
 273 /* Give PID the flags FLAGS in the PID_LIST array. */
 274 static void
 275 set_pid_flags (pid, flags)
 276      pid_t pid;
 277      int flags;
 278 {
 279   int slot;
 280
 281   slot = find_index_by_pid (pid);
 282   if (slot == NO_PID)
 283     return;
 284
 285   pid_list[slot].flags |= flags;
 286 }
 287
 288 /* Unset FLAGS for PID in the pid list */
 289 static void
 290 unset_pid_flags (pid, flags)
 291      pid_t pid;
 292      int flags;
 293 {
 294   int slot;
 295
 296   slot = find_index_by_pid (pid);
 297   if (slot == NO_PID)
 298     return;
 299
 300   pid_list[slot].flags &= ~flags;
 301 }
 302
 303 /* Return the flags corresponding to PID in the PID_LIST array. */
 304 static int
 305 get_pid_flags (pid)
 306      pid_t pid;
 307 {
 308   int slot;
 309
 310   slot = find_index_by_pid (pid);
 311   if (slot == NO_PID)
 312     return 0;
 313
 314   return (pid_list[slot].flags);
 315 }
 316
 317 static void
 318 add_pid (pid, async)
 319      pid_t pid;
 320      int async;
 321 {
 322   int slot;
 323
 324   slot = find_proc_slot ();
 325
 326   pid_list[slot].pid = pid;
 327   pid_list[slot].status = -1;
 328   pid_list[slot].flags = PROC_RUNNING;
 329   if (async)
 330     pid_list[slot].flags |= PROC_ASYNC;
 331 }
 332
 333 static void
 334 mark_dead_jobs_as_notified (force)
 335      int force;
 336 {
 337   register int i, ndead;
 338
 339   /* first, count the number of non-running async jobs if FORCE == 0 */
 340   for (i = ndead = 0; force == 0 && i < pid_list_size; i++)
 341     {
 342       if (pid_list[i].pid == NO_PID)
 343         continue;
 344       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 345            (pid_list[i].flags & PROC_ASYNC))
 346         ndead++;
 347     }
 348
 349   if (child_max < 0)
 350     child_max = getmaxchild ();
 351   if (child_max < 0)
 352     child_max = DEFAULT_CHILD_MAX;
 353
 354   if (force == 0 && ndead <= child_max)
 355     return;
 356
 357   /* If FORCE == 0, we just mark as many non-running async jobs as notified
 358      to bring us under the CHILD_MAX limit. */
 359   for (i = 0; i < pid_list_size; i++)
 360     {
 361       if (pid_list[i].pid == NO_PID)
 362         continue;
 363       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 364            pid_list[i].pid != last_asynchronous_pid)
 365         {
 366           pid_list[i].flags |= PROC_NOTIFIED;
 367           if (force == 0 && (pid_list[i].flags & PROC_ASYNC) && --ndead <= child_max)
 368             break;
 369         }
 370     }
 371 }
 372
 373 /* Remove all dead, notified jobs from the pid_list. */
 374 int
 375 cleanup_dead_jobs ()
 376 {
 377   register int i;
 378
 379 #if defined (HAVE_WAITPID)
 380   reap_zombie_children ();
 381 #endif
 382
 383   for (i = 0; i < pid_list_size; i++)
 384     {
 385       if ((pid_list[i].flags & PROC_RUNNING) == 0 &&
 386           (pid_list[i].flags & PROC_NOTIFIED))
 387         pid_list[i].pid = NO_PID;
 388     }
 389
 390   return 0;
 391 }
 392
 393 void
 394 reap_dead_jobs ()
 395 {
 396   mark_dead_jobs_as_notified (0);
 397   cleanup_dead_jobs ();
 398 }
 399
 400 /* Initialize the job control mechanism, and set up the tty stuff. */
 401 initialize_job_control (force)
 402      int force;
 403 {
 404   shell_tty = fileno (stderr);
 405
 406   if (interactive)
 407     get_tty_state ();
 408 }
 409
 410 /* Setup this shell to handle C-C, etc. */
 411 void
 412 initialize_job_signals ()
 413 {
 414   set_signal_handler (SIGINT, sigint_sighandler);
 415
 416   /* If this is a login shell we don't wish to be disturbed by
 417      stop signals. */
 418   if (login_shell)
 419     ignore_tty_job_signals ();
 420 }
 421
 422 #if defined (HAVE_WAITPID)
 423 /* Collect the status of all zombie children so that their system
 424    resources can be deallocated. */
 425 static void
 426 reap_zombie_children ()
 427 {
 428 #  if defined (WNOHANG)
 429   pid_t pid;
 430   WAIT status;
 431
 432   CHECK_TERMSIG;
 433   while ((pid = waitpid (-1, (int *)&status, WNOHANG)) > 0)
 434     set_pid_status (pid, status);
 435 #  endif /* WNOHANG */
 436   CHECK_TERMSIG;
 437 }
 438 #endif /* WAITPID */
 439
 440 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 441 static int
 442 siginterrupt (sig, flag)
 443      int sig, flag;
 444 {
 445   struct sigaction act;
 446
 447   sigaction (sig, (struct sigaction *)NULL, &act);
 448
 449   if (flag)
 450     act.sa_flags &= ~SA_RESTART;
 451   else
 452     act.sa_flags |= SA_RESTART;
 453
 454   return (sigaction (sig, &act, (struct sigaction *)NULL));
 455 }
 456 #endif /* !HAVE_SIGINTERRUPT && HAVE_POSIX_SIGNALS */
 457
 458 /* Fork, handling errors.  Returns the pid of the newly made child, or 0.
 459    COMMAND is just for remembering the name of the command; we don't do
 460    anything else with it.  ASYNC_P says what to do with the tty.  If
 461    non-zero, then don't give it away. */
 462 pid_t
 463 make_child (command, async_p)
 464      char *command;
 465      int async_p;
 466 {
 467   pid_t pid;
 468 #if defined (HAVE_WAITPID)
 469   int retry = 1;
 470 #endif /* HAVE_WAITPID */
 471
 472   /* Discard saved memory. */
 473   if (command)
 474     free (command);
 475
 476   start_pipeline ();
 477
 478 #if defined (BUFFERED_INPUT)
 479   /* If default_buffered_input is active, we are reading a script.  If
 480      the command is asynchronous, we have already duplicated /dev/null
 481      as fd 0, but have not changed the buffered stream corresponding to
 482      the old fd 0.  We don't want to sync the stream in this case. */
 483   if (default_buffered_input != -1 && (!async_p || default_buffered_input > 0))
 484     sync_buffered_stream (default_buffered_input);
 485 #endif /* BUFFERED_INPUT */
 486
 487   /* Create the child, handle severe errors. */
 488 #if defined (HAVE_WAITPID)
 489   retry_fork:
 490 #endif /* HAVE_WAITPID */
 491
 492   if ((pid = fork ()) < 0)
 493     {
 494 #if defined (HAVE_WAITPID)
 495       /* Posix systems with a non-blocking waitpid () system call available
 496          get another chance after zombies are reaped. */
 497       if (errno == EAGAIN && retry)
 498         {
 499           reap_zombie_children ();
 500           retry = 0;
 501           goto retry_fork;
 502         }
 503 #endif /* HAVE_WAITPID */
 504
 505       sys_error ("fork");
 506
 507       throw_to_top_level ();
 508     }
 509
 510   if (pid == 0)
 511     {
 512 #if defined (BUFFERED_INPUT)
 513       unset_bash_input (0);
 514 #endif /* BUFFERED_INPUT */
 515
 516 #if defined (HAVE_POSIX_SIGNALS)
 517       /* Restore top-level signal mask. */
 518       sigprocmask (SIG_SETMASK, &top_level_mask, (sigset_t *)NULL);
 519 #endif
 520
 521       /* Ignore INT and QUIT in asynchronous children. */
 522       if (async_p)
 523         last_asynchronous_pid = getpid ();
 524
 525       default_tty_job_signals ();
 526     }
 527   else
 528     {
 529       /* In the parent. */
 530
 531       last_made_pid = pid;
 532
 533       if (async_p)
 534         last_asynchronous_pid = pid;
 535
 536       add_pid (pid, async_p);
 537     }
 538   return (pid);
 539 }
 540
 541 void
 542 ignore_tty_job_signals ()
 543 {
 544 #if defined (SIGTSTP)
 545   set_signal_handler (SIGTSTP, SIG_IGN);
 546   set_signal_handler (SIGTTIN, SIG_IGN);
 547   set_signal_handler (SIGTTOU, SIG_IGN);
 548 #endif
 549 }
 550
 551 void
 552 default_tty_job_signals ()
 553 {
 554 #if defined (SIGTSTP)
 555   set_signal_handler (SIGTSTP, SIG_DFL);
 556   set_signal_handler (SIGTTIN, SIG_DFL);
 557   set_signal_handler (SIGTTOU, SIG_DFL);
 558 #endif
 559 }
 560
 561 /* Wait for a single pid (PID) and return its exit status.  Called by
 562    the wait builtin. */
 563 int
 564 wait_for_single_pid (pid)
 565      pid_t pid;
 566 {
 567   pid_t got_pid;
 568   WAIT status;
 569   int pstatus, flags;
 570
 571   pstatus = find_status_by_pid (pid);
 572
 573   if (pstatus == PROC_BAD)
 574     {
 575       internal_error (_("wait: pid %ld is not a child of this shell"), (long)pid);
 576       return (127);
 577     }
 578
 579   if (pstatus != PROC_STILL_ALIVE)
 580     {
 581       if (pstatus > 128)
 582         last_command_exit_signal = find_termsig_by_pid (pid);
 583       return (pstatus);
 584     }
 585
 586   siginterrupt (SIGINT, 1);
 587   while ((got_pid = WAITPID (pid, &status, 0)) != pid)
 588     {
 589       CHECK_TERMSIG;
 590       if (got_pid < 0)
 591         {
 592           if (errno != EINTR && errno != ECHILD)
 593             {
 594               siginterrupt (SIGINT, 0);
 595               sys_error ("wait");
 596             }
 597           break;
 598         }
 599       else if (got_pid > 0)
 600         set_pid_status (got_pid, status);
 601     }
 602
 603   if (got_pid > 0)
 604     {
 605       set_pid_status (got_pid, status);
 606       set_pid_flags (got_pid, PROC_NOTIFIED);
 607     }
 608
 609   siginterrupt (SIGINT, 0);
 610   QUIT;
 611
 612   return (got_pid > 0 ? process_exit_status (status) : -1);
 613 }
 614
 615 /* Wait for all of the shell's children to exit.  Called by the `wait'
 616    builtin. */
 617 void
 618 wait_for_background_pids ()
 619 {
 620   pid_t got_pid;
 621   WAIT status;
 622
 623   /* If we aren't using job control, we let the kernel take care of the
 624      bookkeeping for us.  wait () will return -1 and set errno to ECHILD
 625      when there are no more unwaited-for child processes on both
 626      4.2 BSD-based and System V-based systems. */
 627
 628   siginterrupt (SIGINT, 1);
 629
 630   /* Wait for ECHILD */
 631   while ((got_pid = WAITPID (-1, &status, 0)) != -1)
 632     set_pid_status (got_pid, status);
 633
 634   if (errno != EINTR && errno != ECHILD)
 635     {
 636       siginterrupt (SIGINT, 0);
 637       sys_error("wait");
 638     }
 639
 640   siginterrupt (SIGINT, 0);
 641   QUIT;
 642
 643   mark_dead_jobs_as_notified (1);
 644   cleanup_dead_jobs ();
 645 }
 646
 647 /* Make OLD_SIGINT_HANDLER the SIGINT signal handler. */
 648 #define INVALID_SIGNAL_HANDLER (SigHandler *)wait_for_background_pids
 649 static SigHandler *old_sigint_handler = INVALID_SIGNAL_HANDLER;
 650
 651 static void
 652 restore_sigint_handler ()
 653 {
 654   if (old_sigint_handler != INVALID_SIGNAL_HANDLER)
 655     {
 656       set_signal_handler (SIGINT, old_sigint_handler);
 657       old_sigint_handler = INVALID_SIGNAL_HANDLER;
 658     }
 659 }
 660
 661 /* Handle SIGINT while we are waiting for children in a script to exit.
 662    All interrupts are effectively ignored by the shell, but allowed to
 663    kill a running job. */
 664 static sighandler
 665 wait_sigint_handler (sig)
 666      int sig;
 667 {
 668   SigHandler *sigint_handler;
 669
 670   /* If we got a SIGINT while in `wait', and SIGINT is trapped, do
 671      what POSIX.2 says (see builtins/wait.def for more info). */
 672   if (this_shell_builtin && this_shell_builtin == wait_builtin &&
 673       signal_is_trapped (SIGINT) &&
 674       ((sigint_handler = trap_to_sighandler (SIGINT)) == trap_handler))
 675     {
 676       last_command_exit_value = EXECUTION_FAILURE;
 677       restore_sigint_handler ();
 678       interrupt_immediately = 0;
 679       trap_handler (SIGINT);    /* set pending_traps[SIGINT] */
 680       wait_signal_received = SIGINT;
 681       longjmp (wait_intr_buf, 1);
 682     }
 683
 684   if (interrupt_immediately)
 685     {
 686       last_command_exit_value = EXECUTION_FAILURE;
 687       restore_sigint_handler ();
 688       ADDINTERRUPT;
 689       QUIT;
 690     }
 691
 692   wait_sigint_received = 1;
 693
 694   SIGRETURN (0);
 695 }
 696
 697 static char *
 698 j_strsignal (s)
 699      int s;
 700 {
 701   static char retcode_name_buffer[64] = { '\0' };
 702   char *x;
 703
 704   x = strsignal (s);
 705   if (x == 0)
 706     {
 707       x = retcode_name_buffer;
 708       sprintf (x, "Signal %d", s);
 709     }
 710   return x;
 711 }
 712
 713 /* Wait for pid (one of our children) to terminate.  This is called only
 714    by the execution code in execute_cmd.c. */
 715 int
 716 wait_for (pid)
 717      pid_t pid;
 718 {
 719   int return_val, pstatus;
 720   pid_t got_pid;
 721   WAIT status;
 722
 723   pstatus = find_status_by_pid (pid);
 724
 725   if (pstatus == PROC_BAD)
 726     return (0);
 727
 728   if (pstatus != PROC_STILL_ALIVE)
 729     {
 730       if (pstatus > 128)
 731         last_command_exit_signal = find_termsig_by_pid (pid);
 732       return (pstatus);
 733     }
 734
 735   /* If we are running a script, ignore SIGINT while we're waiting for
 736      a child to exit.  The loop below does some of this, but not all. */
 737   wait_sigint_received = 0;
 738   if (interactive_shell == 0)
 739     old_sigint_handler = set_signal_handler (SIGINT, wait_sigint_handler);
 740
 741   while ((got_pid = WAITPID (-1, &status, 0)) != pid) /* XXX was pid now -1 */
 742     {
 743       CHECK_TERMSIG;
 744       if (got_pid < 0 && errno == ECHILD)
 745         {
 746 #if !defined (_POSIX_VERSION)
 747           status.w_termsig = status.w_retcode = 0;
 748 #else
 749           status = 0;
 750 #endif /* _POSIX_VERSION */
 751           break;
 752         }
 753       else if (got_pid < 0 && errno != EINTR)
 754         programming_error ("wait_for(%ld): %s", (long)pid, strerror(errno));
 755       else if (got_pid > 0)
 756         set_pid_status (got_pid, status);
 757     }
 758
 759   if (got_pid > 0)
 760     set_pid_status (got_pid, status);
 761
 762 #if defined (HAVE_WAITPID)
 763   if (got_pid >= 0)
 764     reap_zombie_children ();
 765 #endif /* HAVE_WAITPID */
 766
 767   if (interactive_shell == 0)
 768     {
 769       SigHandler *temp_handler;
 770
 771       temp_handler = old_sigint_handler;
 772       restore_sigint_handler ();
 773
 774       /* If the job exited because of SIGINT, make sure the shell acts as if
 775          it had received one also. */
 776       if (WIFSIGNALED (status) && (WTERMSIG (status) == SIGINT))
 777         {
 778
 779           if (maybe_call_trap_handler (SIGINT) == 0)
 780             {
 781               if (temp_handler == SIG_DFL)
 782                 termsig_handler (SIGINT);
 783               else if (temp_handler != INVALID_SIGNAL_HANDLER && temp_handler != SIG_IGN)
 784                 (*temp_handler) (SIGINT);
 785             }
 786         }
 787     }
 788
 789   /* Default return value. */
 790   /* ``a full 8 bits of status is returned'' */
 791   return_val = process_exit_status (status);
 792   last_command_exit_signal = get_termsig (status);
 793
 794 #if !defined (DONT_REPORT_SIGPIPE)
 795   if ((WIFSTOPPED (status) == 0) && WIFSIGNALED (status) &&
 796         (WTERMSIG (status) != SIGINT))
 797 #else
 798   if ((WIFSTOPPED (status) == 0) && WIFSIGNALED (status) &&
 799         (WTERMSIG (status) != SIGINT) && (WTERMSIG (status) != SIGPIPE))
 800 #endif
 801     {
 802       fprintf (stderr, "%s", j_strsignal (WTERMSIG (status)));
 803       if (WIFCORED (status))
 804         fprintf (stderr, " (core dumped)");
 805       fprintf (stderr, "\n");
 806     }
 807
 808   if (interactive_shell && subshell_environment == 0)
 809     {
 810       if (WIFSIGNALED (status) || WIFSTOPPED (status))
 811         set_tty_state ();
 812       else
 813         get_tty_state ();
 814     }
 815
 816   return (return_val);
 817 }
 818
 819 /* Send PID SIGNAL.  Returns -1 on failure, 0 on success.  If GROUP is non-zero,
 820    or PID is less than -1, then kill the process group associated with PID. */
 821 int
 822 kill_pid (pid, signal, group)
 823      pid_t pid;
 824      int signal, group;
 825 {
 826   int result;
 827
 828   if (pid < -1)
 829     {
 830       pid = -pid;
 831       group = 1;
 832     }
 833   result = group ? killpg (pid, signal) : kill (pid, signal);
 834   return (result);
 835 }
 836
 837 static TTYSTRUCT shell_tty_info;
 838 static int got_tty_state;
 839
 840 /* Fill the contents of shell_tty_info with the current tty info. */
 841 get_tty_state ()
 842 {
 843   int tty;
 844
 845   tty = input_tty ();
 846   if (tty != -1)
 847     {
 848       ttgetattr (tty, &shell_tty_info);
 849       got_tty_state = 1;
 850       if (check_window_size)
 851         get_new_window_size (0, (int *)0, (int *)0);
 852     }
 853 }
 854
 855 /* Make the current tty use the state in shell_tty_info. */
 856 int
 857 set_tty_state ()
 858 {
 859   int tty;
 860
 861   tty = input_tty ();
 862   if (tty != -1)
 863     {
 864       if (got_tty_state == 0)
 865         return 0;
 866       ttsetattr (tty, &shell_tty_info);
 867     }
 868   return 0;
 869 }
 870
 871 /* Give the terminal to PGRP.  */
 872 give_terminal_to (pgrp, force)
 873      pid_t pgrp;
 874      int force;
 875 {
 876 }
 877
 878 /* Stop a pipeline. */
 879 int
 880 stop_pipeline (async, ignore)
 881      int async;
 882      COMMAND *ignore;
 883 {
 884   already_making_children = 0;
 885   return 0;
 886 }
 887
 888 void
 889 start_pipeline ()
 890 {
 891   already_making_children = 1;
 892 }
 893
 894 void
 895 stop_making_children ()
 896 {
 897   already_making_children = 0;
 898 }
 899
 900 int
 901 get_job_by_pid (pid, block)
 902      pid_t pid;
 903      int block;
 904 {
 905   int i;
 906
 907   i = find_index_by_pid (pid);
 908   return ((i == NO_PID) ? PROC_BAD : i);
 909 }
 910
 911 /* Print descriptive information about the job with leader pid PID. */
 912 void
 913 describe_pid (pid)
 914      pid_t pid;
 915 {
 916   fprintf (stderr, "%ld\n", (long) pid);
 917 }
 918
 919 void
 920 unfreeze_jobs_list ()
 921 {
 922 }
 923
 924 int
 925 count_all_jobs ()
 926 {
 927   return 0;
 928 }