builtins/kill.def

   1 This file is kill.def, from which is created kill.c.
   2 It implements the builtin "kill" in Bash.
   3
   4 Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
   5
   6 This file is part of GNU Bash, the Bourne Again SHell.
   7
   8 Bash is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 Bash is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License along
  19 with Bash; see the file COPYING.  If not, write to the Free Software
  20 Foundation, 59 Temple Place, Suite 330, Boston, MA 02111 USA.
  21
  22 $PRODUCES kill.c
  23
  24 $BUILTIN kill
  25 $FUNCTION kill_builtin
  26 $DEPENDS_ON JOB_CONTROL
  27 $SHORT_DOC kill [-s sigspec | -n signum | -sigspec] [pid | job]... or kill -l [sigspec]
  28 Send the processes named by PID (or JOB) the signal SIGSPEC.  If
  29 SIGSPEC is not present, then SIGTERM is assumed.  An argument of `-l'
  30 lists the signal names; if arguments follow `-l' they are assumed to
  31 be signal numbers for which names should be listed.  Kill is a shell
  32 builtin for two reasons: it allows job IDs to be used instead of
  33 process IDs, and, if you have reached the limit on processes that
  34 you can create, you don't have to start a process to kill another one.
  35 $END
  36
  37 #include <config.h>
  38
  39 #include <stdio.h>
  40 #include <errno.h>
  41 #if defined (HAVE_UNISTD_H)
  42 #  ifdef _MINIX
  43 #    include <sys/types.h>
  44 #  endif
  45 #  include <unistd.h>
  46 #endif
  47
  48 #include "../bashansi.h"
  49
  50 #include "../shell.h"
  51 #include "../trap.h"
  52 #include "../jobs.h"
  53 #include "common.h"
  54
  55 /* Not all systems declare ERRNO in errno.h... and some systems #define it! */
  56 #if !defined (errno)
  57 extern int errno;
  58 #endif /* !errno */
  59
  60 #if defined (JOB_CONTROL)
  61 extern int interactive;
  62 extern int job_control;
  63 extern int posixly_correct;
  64
  65 #if !defined (CONTINUE_AFTER_KILL_ERROR)
  66 #  define CONTINUE_OR_FAIL return (EXECUTION_FAILURE)
  67 #else
  68 #  define CONTINUE_OR_FAIL goto continue_killing
  69 #endif /* CONTINUE_AFTER_KILL_ERROR */
  70
  71 /* Here is the kill builtin.  We only have it so that people can type
  72    kill -KILL %1?  No, if you fill up the process table this way you
  73    can still kill some. */
  74 int
  75 kill_builtin (list)
  76      WORD_LIST *list;
  77 {
  78   int signal, any_succeeded, listing, saw_signal;
  79   char *sigspec, *word;
  80   pid_t pid;
  81
  82   if (list == 0)
  83     {
  84       builtin_usage ();
  85       return (EXECUTION_FAILURE);
  86     }
  87
  88   any_succeeded = listing = saw_signal = 0;
  89   signal = SIGTERM;
  90   sigspec = "TERM";
  91
  92   /* Process options. */
  93   while (list)
  94     {
  95       word = list->word->word;
  96
  97       if (ISOPTION (word, 'l'))
  98         {
  99           listing++;
 100           list = list->next;
 101         }
 102       else if (ISOPTION (word, 's') || ISOPTION (word, 'n'))
 103         {
 104           list = list->next;
 105           if (list)
 106             {
 107               sigspec = list->word->word;
 108               if (sigspec[0] == '0' && sigspec[1] == '\0')
 109                 signal = 0;
 110               else
 111                 signal = decode_signal (sigspec);
 112               list = list->next;
 113             }
 114           else
 115             {
 116               builtin_error ("%s requires an argument", word);
 117               return (EXECUTION_FAILURE);
 118             }
 119         }
 120       else if (ISOPTION (word, '-'))
 121         {
 122           list = list->next;
 123           break;
 124         }
 125       else if (ISOPTION (word, '?'))
 126         {
 127           builtin_usage ();
 128           return (EXECUTION_SUCCESS);
 129         }
 130       /* If this is a signal specification then process it.  We only process
 131          the first one seen; other arguments may signify process groups (e.g,
 132          -num == process group num). */
 133       else if ((*word == '-') && !saw_signal)
 134         {
 135           sigspec = word + 1;
 136           signal = decode_signal (sigspec);
 137           saw_signal++;
 138           list = list->next;
 139         }
 140       else
 141         break;
 142     }
 143
 144   if (listing)
 145     return (display_signal_list (list, 0));
 146
 147   /* OK, we are killing processes. */
 148   if (signal == NO_SIG)
 149     {
 150       builtin_error ("bad signal spec `%s'", sigspec);
 151       return (EXECUTION_FAILURE);
 152     }
 153
 154   if (list == 0)
 155     {
 156       builtin_usage ();
 157       return (EXECUTION_FAILURE);
 158     }
 159
 160   while (list)
 161     {
 162       word = list->word->word;
 163
 164       if (*word == '-')
 165         word++;
 166
 167       if (*word && all_digits (word))
 168         {
 169           /* Use the entire argument in case of minus sign presence. */
 170           pid = (pid_t) atoi (list->word->word);
 171
 172           if (kill_pid (pid, signal, 0) < 0)
 173             goto signal_error;
 174           else
 175             any_succeeded++;
 176         }
 177       else if (*list->word->word && *list->word->word != '%')
 178         {
 179           builtin_error ("%s: no such pid", list->word->word);
 180           CONTINUE_OR_FAIL;
 181         }
 182       else if (*word && (interactive || job_control))
 183         /* Posix.2 says you can kill without job control active (4.32.4) */
 184         {                       /* Must be a job spec.  Check it out. */
 185           int job;
 186           sigset_t set, oset;
 187
 188           BLOCK_CHILD (set, oset);
 189           job = get_job_spec (list);
 190
 191           if (job < 0 || job >= job_slots || !jobs[job])
 192             {
 193               if (job != DUP_JOB)
 194                 builtin_error ("%s: no such job", list->word->word);
 195               UNBLOCK_CHILD (oset);
 196               CONTINUE_OR_FAIL;
 197             }
 198
 199           /* Job spec used.  Kill the process group. If the job was started
 200              without job control, then its pgrp == shell_pgrp, so we have
 201              to be careful.  We take the pid of the first job in the pipeline
 202              in that case. */
 203           pid = IS_JOBCONTROL (job) ? jobs[job]->pgrp : jobs[job]->pipe->pid;
 204
 205           UNBLOCK_CHILD (oset);
 206
 207           if (kill_pid (pid, signal, 1) < 0)
 208             {
 209             signal_error:
 210               if (errno == EPERM)
 211                 builtin_error ("(%d) - Not owner", (int)pid);
 212               else if (errno == ESRCH)
 213                 builtin_error ("(%d) - No such pid", (int)pid);
 214               else
 215                 builtin_error ("Invalid signal %d", signal);
 216               CONTINUE_OR_FAIL;
 217             }
 218           else
 219             any_succeeded++;
 220         }
 221       else
 222         {
 223           builtin_error ("`%s': not a pid or valid job spec", list->word->word);
 224           CONTINUE_OR_FAIL;
 225         }
 226     continue_killing:
 227       list = list->next;
 228     }
 229
 230   return (any_succeeded ? EXECUTION_SUCCESS : EXECUTION_FAILURE);
 231 }
 232 #endif /* JOB_CONTROL */