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) 1987-2009 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 pid_t last_made_pid = NO_PID;
  87 pid_t last_asynchronous_pid = NO_PID;
  88
  89 /* Call this when you start making children. */
  90 int already_making_children = 0;
  91
  92 /* The controlling tty for this shell. */
  93 int shell_tty = -1;
  94
  95 /* If this is non-zero, $LINES and $COLUMNS are reset after every process
  96    exits from get_tty_state(). */
  97 int check_window_size;
  98
  99 /* STATUS and FLAGS are only valid if pid != NO_PID
 100    STATUS is only valid if (flags & PROC_RUNNING) == 0 */
 101 struct proc_status {
 102   pid_t pid;
 103   int status;   /* Exit status of PID or 128 + fatal signal number */
 104   int flags;
 105 };
 106
 107 /* Values for proc_status.flags */
 108 #define PROC_RUNNING    0x01
 109 #define PROC_NOTIFIED   0x02
 110 #define PROC_ASYNC      0x04
 111 #define PROC_SIGNALED   0x10
 112
 113 /* Return values from find_status_by_pid */
 114 #define PROC_BAD         -1
 115 #define PROC_STILL_ALIVE -2
 116
 117 static struct proc_status *pid_list = (struct proc_status *)NULL;
 118 static int pid_list_size;
 119 static int wait_sigint_received;
 120
 121 static long child_max = -1L;
 122
 123 static void alloc_pid_list __P((void));
 124 static int find_proc_slot __P((void));
 125 static int find_index_by_pid __P((pid_t));
 126 static int find_status_by_pid __P((pid_t));
 127 static int process_exit_status __P((WAIT));
 128 static int find_termsig_by_pid __P((pid_t));
 129 static int get_termsig __P((WAIT));
 130 static void set_pid_status __P((pid_t, WAIT));
 131 static void set_pid_flags __P((pid_t, int));
 132 static void unset_pid_flags __P((pid_t, int));
 133 static int get_pid_flags __P((pid_t));
 134 static void add_pid __P((pid_t, int));
 135 static void mark_dead_jobs_as_notified __P((int));
 136
 137 static sighandler wait_sigint_handler __P((int));
 138 static char *j_strsignal __P((int));
 139
 140 #if defined (HAVE_WAITPID)
 141 static void reap_zombie_children __P((void));
 142 #endif
 143
 144 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 145 static int siginterrupt __P((int, int));
 146 #endif
 147
 148 static void restore_sigint_handler __P((void));
 149
 150 /* Allocate new, or grow existing PID_LIST. */
 151 static void
 152 alloc_pid_list ()
 153 {
 154   register int i;
 155   int old = pid_list_size;
 156
 157   pid_list_size += 10;
 158   pid_list = (struct proc_status *)xrealloc (pid_list, pid_list_size * sizeof (struct proc_status));
 159
 160   /* None of the newly allocated slots have process id's yet. */
 161   for (i = old; i < pid_list_size; i++)
 162     pid_list[i].pid = NO_PID;
 163 }
 164
 165 /* Return the offset within the PID_LIST array of an empty slot.  This can
 166    create new slots if all of the existing slots are taken. */
 167 static int
 168 find_proc_slot ()
 169 {
 170   register int i;
 171
 172   for (i = 0; i < pid_list_size; i++)
 173     if (pid_list[i].pid == NO_PID)
 174       return (i);
 175
 176   if (i == pid_list_size)
 177     alloc_pid_list ();
 178
 179   return (i);
 180 }
 181
 182 /* Return the offset within the PID_LIST array of a slot containing PID,
 183    or the value NO_PID if the pid wasn't found. */
 184 static int
 185 find_index_by_pid (pid)
 186      pid_t pid;
 187 {
 188   register int i;
 189
 190   for (i = 0; i < pid_list_size; i++)
 191     if (pid_list[i].pid == pid)
 192       return (i);
 193
 194   return (NO_PID);
 195 }
 196
 197 /* Return the status of PID as looked up in the PID_LIST array.  A
 198    return value of PROC_BAD indicates that PID wasn't found. */
 199 static int
 200 find_status_by_pid (pid)
 201      pid_t pid;
 202 {
 203   int i;
 204
 205   i = find_index_by_pid (pid);
 206   if (i == NO_PID)
 207     return (PROC_BAD);
 208   if (pid_list[i].flags & PROC_RUNNING)
 209     return (PROC_STILL_ALIVE);
 210   return (pid_list[i].status);
 211 }
 212
 213 static int
 214 process_exit_status (status)
 215      WAIT status;
 216 {
 217   if (WIFSIGNALED (status))
 218     return (128 + WTERMSIG (status));
 219   else
 220     return (WEXITSTATUS (status));
 221 }
 222
 223 /* Return the status of PID as looked up in the PID_LIST array.  A
 224    return value of PROC_BAD indicates that PID wasn't found. */
 225 static int
 226 find_termsig_by_pid (pid)
 227      pid_t pid;
 228 {
 229   int i;
 230
 231   i = find_index_by_pid (pid);
 232   if (i == NO_PID)
 233     return (0);
 234   if (pid_list[i].flags & PROC_RUNNING)
 235     return (0);
 236   return (get_termsig ((WAIT)pid_list[i].status));
 237 }
 238
 239 /* Set LAST_COMMAND_EXIT_SIGNAL depending on STATUS.  If STATUS is -1, look
 240    up PID in the pid array and set LAST_COMMAND_EXIT_SIGNAL appropriately
 241    depending on its flags and exit status. */
 242 static int
 243 get_termsig (status)
 244      WAIT status;
 245 {
 246   if (WIFSTOPPED (status) == 0 && WIFSIGNALED (status))
 247     return (WTERMSIG (status));
 248   else
 249     return (0);
 250 }
 251
 252 /* Give PID the status value STATUS in the PID_LIST array. */
 253 static void
 254 set_pid_status (pid, status)
 255      pid_t pid;
 256      WAIT status;
 257 {
 258   int slot;
 259
 260 #if defined (COPROCESS_SUPPORT)
 261   coproc_pidchk (pid, status);
 262 #endif
 263
 264   slot = find_index_by_pid (pid);
 265   if (slot == NO_PID)
 266     return;
 267
 268   pid_list[slot].status = process_exit_status (status);
 269   pid_list[slot].flags &= ~PROC_RUNNING;
 270   if (WIFSIGNALED (status))
 271     pid_list[slot].flags |= PROC_SIGNALED;
 272   /* If it's not a background process, mark it as notified so it gets
 273      cleaned up. */
 274   if ((pid_list[slot].flags & PROC_ASYNC) == 0)
 275     pid_list[slot].flags |= PROC_NOTIFIED;
 276 }
 277
 278 /* Give PID the flags FLAGS in the PID_LIST array. */
 279 static void
 280 set_pid_flags (pid, flags)
 281      pid_t pid;
 282      int flags;
 283 {
 284   int slot;
 285
 286   slot = find_index_by_pid (pid);
 287   if (slot == NO_PID)
 288     return;
 289
 290   pid_list[slot].flags |= flags;
 291 }
 292
 293 /* Unset FLAGS for PID in the pid list */
 294 static void
 295 unset_pid_flags (pid, flags)
 296      pid_t pid;
 297      int flags;
 298 {
 299   int slot;
 300
 301   slot = find_index_by_pid (pid);
 302   if (slot == NO_PID)
 303     return;
 304
 305   pid_list[slot].flags &= ~flags;
 306 }
 307
 308 /* Return the flags corresponding to PID in the PID_LIST array. */
 309 static int
 310 get_pid_flags (pid)
 311      pid_t pid;
 312 {
 313   int slot;
 314
 315   slot = find_index_by_pid (pid);
 316   if (slot == NO_PID)
 317     return 0;
 318
 319   return (pid_list[slot].flags);
 320 }
 321
 322 static void
 323 add_pid (pid, async)
 324      pid_t pid;
 325      int async;
 326 {
 327   int slot;
 328
 329   slot = find_proc_slot ();
 330
 331   pid_list[slot].pid = pid;
 332   pid_list[slot].status = -1;
 333   pid_list[slot].flags = PROC_RUNNING;
 334   if (async)
 335     pid_list[slot].flags |= PROC_ASYNC;
 336 }
 337
 338 static void
 339 mark_dead_jobs_as_notified (force)
 340      int force;
 341 {
 342   register int i, ndead;
 343
 344   /* first, count the number of non-running async jobs if FORCE == 0 */
 345   for (i = ndead = 0; force == 0 && i < pid_list_size; i++)
 346     {
 347       if (pid_list[i].pid == NO_PID)
 348         continue;
 349       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 350            (pid_list[i].flags & PROC_ASYNC))
 351         ndead++;
 352     }
 353
 354   if (child_max < 0)
 355     child_max = getmaxchild ();
 356   if (child_max < 0)
 357     child_max = DEFAULT_CHILD_MAX;
 358
 359   if (force == 0 && ndead <= child_max)
 360     return;
 361
 362   /* If FORCE == 0, we just mark as many non-running async jobs as notified
 363      to bring us under the CHILD_MAX limit. */
 364   for (i = 0; i < pid_list_size; i++)
 365     {
 366       if (pid_list[i].pid == NO_PID)
 367         continue;
 368       if (((pid_list[i].flags & PROC_RUNNING) == 0) &&
 369            pid_list[i].pid != last_asynchronous_pid)
 370         {
 371           pid_list[i].flags |= PROC_NOTIFIED;
 372           if (force == 0 && (pid_list[i].flags & PROC_ASYNC) && --ndead <= child_max)
 373             break;
 374         }
 375     }
 376 }
 377
 378 /* Remove all dead, notified jobs from the pid_list. */
 379 int
 380 cleanup_dead_jobs ()
 381 {
 382   register int i;
 383
 384 #if defined (HAVE_WAITPID)
 385   reap_zombie_children ();
 386 #endif
 387
 388   for (i = 0; i < pid_list_size; i++)
 389     {
 390       if ((pid_list[i].flags & PROC_RUNNING) == 0 &&
 391           (pid_list[i].flags & PROC_NOTIFIED))
 392         pid_list[i].pid = NO_PID;
 393     }
 394
 395 #if defined (COPROCESS_SUPPORT)
 396   coproc_reap ();
 397 #endif
 398
 399   return 0;
 400 }
 401
 402 void
 403 reap_dead_jobs ()
 404 {
 405   mark_dead_jobs_as_notified (0);
 406   cleanup_dead_jobs ();
 407 }
 408
 409 /* Initialize the job control mechanism, and set up the tty stuff. */
 410 initialize_job_control (force)
 411      int force;
 412 {
 413   shell_tty = fileno (stderr);
 414
 415   if (interactive)
 416     get_tty_state ();
 417 }
 418
 419 /* Setup this shell to handle C-C, etc. */
 420 void
 421 initialize_job_signals ()
 422 {
 423   set_signal_handler (SIGINT, sigint_sighandler);
 424
 425   /* If this is a login shell we don't wish to be disturbed by
 426      stop signals. */
 427   if (login_shell)
 428     ignore_tty_job_signals ();
 429 }
 430
 431 #if defined (HAVE_WAITPID)
 432 /* Collect the status of all zombie children so that their system
 433    resources can be deallocated. */
 434 static void
 435 reap_zombie_children ()
 436 {
 437 #  if defined (WNOHANG)
 438   pid_t pid;
 439   WAIT status;
 440
 441   CHECK_TERMSIG;
 442   while ((pid = waitpid (-1, (int *)&status, WNOHANG)) > 0)
 443     set_pid_status (pid, status);
 444 #  endif /* WNOHANG */
 445   CHECK_TERMSIG;
 446 }
 447 #endif /* WAITPID */
 448
 449 #if !defined (HAVE_SIGINTERRUPT) && defined (HAVE_POSIX_SIGNALS)
 450 static int
 451 siginterrupt (sig, flag)
 452      int sig, flag;
 453 {
 454   struct sigaction act;
 455
 456   sigaction (sig, (struct sigaction *)NULL, &act);
 457
 458   if (flag)
 459     act.sa_flags &= ~SA_RESTART;
 460   else
 461     act.sa_flags |= SA_RESTART;
 462
 463   return (sigaction (sig, &act, (struct sigaction *)NULL));
 464 }
 465 #endif /* !HAVE_SIGINTERRUPT && HAVE_POSIX_SIGNALS */
 466
 467 /* Fork, handling errors.  Returns the pid of the newly made child, or 0.
 468    COMMAND is just for remembering the name of the command; we don't do
 469    anything else with it.  ASYNC_P says what to do with the tty.  If
 470    non-zero, then don't give it away. */
 471 pid_t
 472 make_child (command, async_p)
 473      char *command;
 474      int async_p;
 475 {
 476   pid_t pid;
 477   int forksleep;
 478
 479   /* Discard saved memory. */
 480   if (command)
 481     free (command);
 482
 483   start_pipeline ();
 484
 485 #if defined (BUFFERED_INPUT)
 486   /* If default_buffered_input is active, we are reading a script.  If
 487      the command is asynchronous, we have already duplicated /dev/null
 488      as fd 0, but have not changed the buffered stream corresponding to
 489      the old fd 0.  We don't want to sync the stream in this case. */
 490   if (default_buffered_input != -1 && (!async_p || default_buffered_input > 0))
 491     sync_buffered_stream (default_buffered_input);
 492 #endif /* BUFFERED_INPUT */
 493
 494   /* Create the child, handle severe errors.  Retry on EAGAIN. */
 495   forksleep = 1;
 496   while ((pid = fork ()) < 0 && errno == EAGAIN && forksleep < FORKSLEEP_MAX)
 497     {
 498       sys_error ("fork: retry");
 499 #if defined (HAVE_WAITPID)
 500       /* Posix systems with a non-blocking waitpid () system call available
 501          get another chance after zombies are reaped. */
 502       reap_zombie_children ();
 503       if (forksleep > 1 && sleep (forksleep) != 0)
 504         break;
 505 #else
 506       if (sleep (forksleep) != 0)
 507         break;
 508 #endif /* HAVE_WAITPID */
 509       forksleep <<= 1;
 510     }
 511
 512   if (pid < 0)
 513     {
 514       sys_error ("fork");
 515       throw_to_top_level ();
 516     }
 517
 518   if (pid == 0)
 519     {
 520 #if defined (BUFFERED_INPUT)
 521       unset_bash_input (0);
 522 #endif /* BUFFERED_INPUT */
 523
 524 #if defined (HAVE_POSIX_SIGNALS)
 525       /* Restore top-level signal mask. */
 526       sigprocmask (SIG_SETMASK, &top_level_mask, (sigset_t *)NULL);
 527 #endif
 528
 529 #if 0
 530       /* Ignore INT and QUIT in asynchronous children. */
 531       if (async_p)
 532         last_asynchronous_pid = getpid ();
 533 #endif
 534
 535       default_tty_job_signals ();
 536     }
 537   else
 538     {
 539       /* In the parent. */
 540
 541       last_made_pid = pid;
 542
 543       if (async_p)
 544         last_asynchronous_pid = pid;
 545
 546       add_pid (pid, async_p);
 547     }
 548   return (pid);
 549 }
 550
 551 void
 552 ignore_tty_job_signals ()
 553 {
 554 #if defined (SIGTSTP)
 555   set_signal_handler (SIGTSTP, SIG_IGN);
 556   set_signal_handler (SIGTTIN, SIG_IGN);
 557   set_signal_handler (SIGTTOU, SIG_IGN);
 558 #endif
 559 }
 560
 561 void
 562 default_tty_job_signals ()
 563 {
 564 #if defined (SIGTSTP)
 565   set_signal_handler (SIGTSTP, SIG_DFL);
 566   set_signal_handler (SIGTTIN, SIG_DFL);
 567   set_signal_handler (SIGTTOU, SIG_DFL);
 568 #endif
 569 }
 570
 571 /* Wait for a single pid (PID) and return its exit status.  Called by
 572    the wait builtin. */
 573 int
 574 wait_for_single_pid (pid)
 575      pid_t pid;
 576 {
 577   pid_t got_pid;
 578   WAIT status;
 579   int pstatus, flags;
 580
 581   pstatus = find_status_by_pid (pid);
 582
 583   if (pstatus == PROC_BAD)
 584     {
 585       internal_error (_("wait: pid %ld is not a child of this shell"), (long)pid);
 586       return (127);
 587     }
 588
 589   if (pstatus != PROC_STILL_ALIVE)
 590     {
 591       if (pstatus > 128)
 592         last_command_exit_signal = find_termsig_by_pid (pid);
 593       return (pstatus);
 594     }
 595
 596   siginterrupt (SIGINT, 1);
 597   while ((got_pid = WAITPID (pid, &status, 0)) != pid)
 598     {
 599       CHECK_TERMSIG;
 600       if (got_pid < 0)
 601         {
 602           if (errno != EINTR && errno != ECHILD)
 603             {
 604               siginterrupt (SIGINT, 0);
 605               sys_error ("wait");
 606             }
 607           break;
 608         }
 609       else if (got_pid > 0)
 610         set_pid_status (got_pid, status);
 611     }
 612
 613   if (got_pid > 0)
 614     {
 615       set_pid_status (got_pid, status);
 616       set_pid_flags (got_pid, PROC_NOTIFIED);
 617     }
 618
 619   siginterrupt (SIGINT, 0);
 620   QUIT;
 621
 622   return (got_pid > 0 ? process_exit_status (status) : -1);
 623 }
 624
 625 /* Wait for all of the shell's children to exit.  Called by the `wait'
 626    builtin. */
 627 void
 628 wait_for_background_pids ()
 629 {
 630   pid_t got_pid;
 631   WAIT status;
 632
 633   /* If we aren't using job control, we let the kernel take care of the
 634      bookkeeping for us.  wait () will return -1 and set errno to ECHILD
 635      when there are no more unwaited-for child processes on both
 636      4.2 BSD-based and System V-based systems. */
 637
 638   siginterrupt (SIGINT, 1);
 639
 640   /* Wait for ECHILD */
 641   while ((got_pid = WAITPID (-1, &status, 0)) != -1)
 642     set_pid_status (got_pid, status);
 643
 644   if (errno != EINTR && errno != ECHILD)
 645     {
 646       siginterrupt (SIGINT, 0);
 647       sys_error("wait");
 648     }
 649
 650   siginterrupt (SIGINT, 0);
 651   QUIT;
 652
 653   mark_dead_jobs_as_notified (1);
 654   cleanup_dead_jobs ();
 655 }
 656
 657 /* Make OLD_SIGINT_HANDLER the SIGINT signal handler. */
 658 #define INVALID_SIGNAL_HANDLER (SigHandler *)wait_for_background_pids
 659 static SigHandler *old_sigint_handler = INVALID_SIGNAL_HANDLER;
 660
 661 static void
 662 restore_sigint_handler ()
 663 {
 664   if (old_sigint_handler != INVALID_SIGNAL_HANDLER)
 665     {
 666       set_signal_handler (SIGINT, old_sigint_handler);
 667       old_sigint_handler = INVALID_SIGNAL_HANDLER;
 668     }
 669 }
 670
 671 /* Handle SIGINT while we are waiting for children in a script to exit.
 672    All interrupts are effectively ignored by the shell, but allowed to
 673    kill a running job. */
 674 static sighandler
 675 wait_sigint_handler (sig)
 676      int sig;
 677 {
 678   SigHandler *sigint_handler;
 679
 680   /* If we got a SIGINT while in `wait', and SIGINT is trapped, do
 681      what POSIX.2 says (see builtins/wait.def for more info). */
 682   if (this_shell_builtin && this_shell_builtin == wait_builtin &&
 683       signal_is_trapped (SIGINT) &&
 684       ((sigint_handler = trap_to_sighandler (SIGINT)) == trap_handler))
 685     {
 686       last_command_exit_value = EXECUTION_FAILURE;
 687       restore_sigint_handler ();
 688       interrupt_immediately = 0;
 689       trap_handler (SIGINT);    /* set pending_traps[SIGINT] */
 690       wait_signal_received = SIGINT;
 691       longjmp (wait_intr_buf, 1);
 692     }
 693
 694   if (interrupt_immediately)
 695     {
 696       last_command_exit_value = EXECUTION_FAILURE;
 697       restore_sigint_handler ();
 698       ADDINTERRUPT;
 699       QUIT;
 700     }
 701
 702   wait_sigint_received = 1;
 703
 704   SIGRETURN (0);
 705 }
 706
 707 static char *
 708 j_strsignal (s)
 709      int s;
 710 {
 711   static char retcode_name_buffer[64] = { '\0' };
 712   char *x;
 713
 714   x = strsignal (s);
 715   if (x == 0)
 716     {
 717       x = retcode_name_buffer;
 718       sprintf (x, "Signal %d", s);
 719     }
 720   return x;
 721 }
 722
 723 /* Wait for pid (one of our children) to terminate.  This is called only
 724    by the execution code in execute_cmd.c. */
 725 int
 726 wait_for (pid)
 727      pid_t pid;
 728 {
 729   int return_val, pstatus;
 730   pid_t got_pid;
 731   WAIT status;
 732
 733   pstatus = find_status_by_pid (pid);
 734
 735   if (pstatus == PROC_BAD)
 736     return (0);
 737
 738   if (pstatus != PROC_STILL_ALIVE)
 739     {
 740       if (pstatus > 128)
 741         last_command_exit_signal = find_termsig_by_pid (pid);
 742       return (pstatus);
 743     }
 744
 745   /* If we are running a script, ignore SIGINT while we're waiting for
 746      a child to exit.  The loop below does some of this, but not all. */
 747   wait_sigint_received = 0;
 748   if (interactive_shell == 0)
 749     old_sigint_handler = set_signal_handler (SIGINT, wait_sigint_handler);
 750
 751   while ((got_pid = WAITPID (-1, &status, 0)) != pid) /* XXX was pid now -1 */
 752     {
 753       CHECK_TERMSIG;
 754       if (got_pid < 0 && errno == ECHILD)
 755         {
 756 #if !defined (_POSIX_VERSION)
 757           status.w_termsig = status.w_retcode = 0;
 758 #else
 759           status = 0;
 760 #endif /* _POSIX_VERSION */
 761           break;
 762         }
 763       else if (got_pid < 0 && errno != EINTR)
 764         programming_error ("wait_for(%ld): %s", (long)pid, strerror(errno));
 765       else if (got_pid > 0)
 766         set_pid_status (got_pid, status);
 767     }
 768
 769   if (got_pid > 0)
 770     set_pid_status (got_pid, status);
 771
 772 #if defined (HAVE_WAITPID)
 773   if (got_pid >= 0)
 774     reap_zombie_children ();
 775 #endif /* HAVE_WAITPID */
 776
 777   if (interactive_shell == 0)
 778     {
 779       SigHandler *temp_handler;
 780
 781       temp_handler = old_sigint_handler;
 782       restore_sigint_handler ();
 783
 784       /* If the job exited because of SIGINT, make sure the shell acts as if
 785          it had received one also. */
 786       if (WIFSIGNALED (status) && (WTERMSIG (status) == SIGINT))
 787         {
 788
 789           if (maybe_call_trap_handler (SIGINT) == 0)
 790             {
 791               if (temp_handler == SIG_DFL)
 792                 termsig_handler (SIGINT);
 793               else if (temp_handler != INVALID_SIGNAL_HANDLER && temp_handler != SIG_IGN)
 794                 (*temp_handler) (SIGINT);
 795             }
 796         }
 797     }
 798
 799   /* Default return value. */
 800   /* ``a full 8 bits of status is returned'' */
 801   return_val = process_exit_status (status);
 802   last_command_exit_signal = get_termsig (status);
 803
 804 #if !defined (DONT_REPORT_SIGPIPE)
 805   if ((WIFSTOPPED (status) == 0) && WIFSIGNALED (status) &&
 806         (WTERMSIG (status) != SIGINT))
 807 #else
 808   if ((WIFSTOPPED (status) == 0) && WIFSIGNALED (status) &&
 809         (WTERMSIG (status) != SIGINT) && (WTERMSIG (status) != SIGPIPE))
 810 #endif
 811     {
 812       fprintf (stderr, "%s", j_strsignal (WTERMSIG (status)));
 813       if (WIFCORED (status))
 814         fprintf (stderr, _(" (core dumped)"));
 815       fprintf (stderr, "\n");
 816     }
 817
 818   if (interactive_shell && subshell_environment == 0)
 819     {
 820       if (WIFSIGNALED (status) || WIFSTOPPED (status))
 821         set_tty_state ();
 822       else
 823         get_tty_state ();
 824     }
 825
 826   return (return_val);
 827 }
 828
 829 /* Send PID SIGNAL.  Returns -1 on failure, 0 on success.  If GROUP is non-zero,
 830    or PID is less than -1, then kill the process group associated with PID. */
 831 int
 832 kill_pid (pid, signal, group)
 833      pid_t pid;
 834      int signal, group;
 835 {
 836   int result;
 837
 838   if (pid < -1)
 839     {
 840       pid = -pid;
 841       group = 1;
 842     }
 843   result = group ? killpg (pid, signal) : kill (pid, signal);
 844   return (result);
 845 }
 846
 847 static TTYSTRUCT shell_tty_info;
 848 static int got_tty_state;
 849
 850 /* Fill the contents of shell_tty_info with the current tty info. */
 851 get_tty_state ()
 852 {
 853   int tty;
 854
 855   tty = input_tty ();
 856   if (tty != -1)
 857     {
 858       ttgetattr (tty, &shell_tty_info);
 859       got_tty_state = 1;
 860       if (check_window_size)
 861         get_new_window_size (0, (int *)0, (int *)0);
 862     }
 863 }
 864
 865 /* Make the current tty use the state in shell_tty_info. */
 866 int
 867 set_tty_state ()
 868 {
 869   int tty;
 870
 871   tty = input_tty ();
 872   if (tty != -1)
 873     {
 874       if (got_tty_state == 0)
 875         return 0;
 876       ttsetattr (tty, &shell_tty_info);
 877     }
 878   return 0;
 879 }
 880
 881 /* Give the terminal to PGRP.  */
 882 give_terminal_to (pgrp, force)
 883      pid_t pgrp;
 884      int force;
 885 {
 886 }
 887
 888 /* Stop a pipeline. */
 889 int
 890 stop_pipeline (async, ignore)
 891      int async;
 892      COMMAND *ignore;
 893 {
 894   already_making_children = 0;
 895   return 0;
 896 }
 897
 898 void
 899 start_pipeline ()
 900 {
 901   already_making_children = 1;
 902 }
 903
 904 void
 905 stop_making_children ()
 906 {
 907   already_making_children = 0;
 908 }
 909
 910 int
 911 get_job_by_pid (pid, block)
 912      pid_t pid;
 913      int block;
 914 {
 915   int i;
 916
 917   i = find_index_by_pid (pid);
 918   return ((i == NO_PID) ? PROC_BAD : i);
 919 }
 920
 921 /* Print descriptive information about the job with leader pid PID. */
 922 void
 923 describe_pid (pid)
 924      pid_t pid;
 925 {
 926   fprintf (stderr, "%ld\n", (long) pid);
 927 }
 928
 929 void
 930 unfreeze_jobs_list ()
 931 {
 932 }
 933
 934 int
 935 count_all_jobs ()
 936 {
 937   return 0;
 938 }