src/kill.c

   1 /* kill -- send a signal to a process
   2    Copyright (C) 2002, 2003, 2004, 2005, 2008-2009 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Paul Eggert.  */
  18
  19 #include <config.h>
  20 #include <stdio.h>
  21 #include <getopt.h>
  22 #include <sys/types.h>
  23 #include <signal.h>
  24
  25 #if HAVE_SYS_WAIT_H
  26 # include <sys/wait.h>
  27 #endif
  28 #ifndef WIFSIGNALED
  29 # define WIFSIGNALED(s) (((s) & 0xFFFF) - 1 < (unsigned int) 0xFF)
  30 #endif
  31 #ifndef WTERMSIG
  32 # define WTERMSIG(s) ((s) & 0x7F)
  33 #endif
  34
  35 #include "system.h"
  36 #include "error.h"
  37 #include "sig2str.h"
  38 #include "operand2sig.h"
  39
  40 /* The official name of this program (e.g., no `g' prefix).  */
  41 #define PROGRAM_NAME "kill"
  42
  43 #define AUTHORS proper_name ("Paul Eggert")
  44 \f
  45 #if ! (HAVE_DECL_STRSIGNAL || defined strsignal)
  46 # if ! (HAVE_DECL_SYS_SIGLIST || defined sys_siglist)
  47 #  if HAVE_DECL__SYS_SIGLIST || defined _sys_siglist
  48 #   define sys_siglist _sys_siglist
  49 #  elif HAVE_DECL___SYS_SIGLIST || defined __sys_siglist
  50 #   define sys_siglist __sys_siglist
  51 #  endif
  52 # endif
  53 # if HAVE_DECL_SYS_SIGLIST || defined sys_siglist
  54 #  define strsignal(signum) (0 <= (signum) && (signum) <= SIGNUM_BOUND \
  55                              ? sys_siglist[signum] \
  56                              : 0)
  57 # endif
  58 # ifndef strsignal
  59 #  define strsignal(signum) 0
  60 # endif
  61 #endif
  62 \f
  63 static char const short_options[] =
  64   "0::1::2::3::4::5::6::7::8::9::"
  65   "A::B::C::D::E::F::G::H::I::J::K::L::M::"
  66   "N::O::P::Q::R::S::T::U::V::W::X::Y::Z::"
  67   "ln:s:t";
  68
  69 static struct option const long_options[] =
  70 {
  71   {"list", no_argument, NULL, 'l'},
  72   {"signal", required_argument, NULL, 's'},
  73   {"table", no_argument, NULL, 't'},
  74   {GETOPT_HELP_OPTION_DECL},
  75   {GETOPT_VERSION_OPTION_DECL},
  76   {NULL, 0, NULL, 0}
  77 };
  78
  79 void
  80 usage (int status)
  81 {
  82   if (status != EXIT_SUCCESS)
  83     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  84              program_name);
  85   else
  86     {
  87       printf (_("\
  88 Usage: %s [-s SIGNAL | -SIGNAL] PID...\n\
  89   or:  %s -l [SIGNAL]...\n\
  90   or:  %s -t [SIGNAL]...\n\
  91 "),
  92               program_name, program_name, program_name);
  93       fputs (_("\
  94 Send signals to processes, or list signals.\n\
  95 \n\
  96 "), stdout);
  97       fputs (_("\
  98 Mandatory arguments to long options are mandatory for short options too.\n\
  99 "), stdout);
 100       fputs (_("\
 101   -s, --signal=SIGNAL, -SIGNAL\n\
 102                    specify the name or number of the signal to be sent\n\
 103   -l, --list       list signal names, or convert signal names to/from numbers\n\
 104   -t, --table      print a table of signal information\n\
 105 "), stdout);
 106       fputs (HELP_OPTION_DESCRIPTION, stdout);
 107       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 108       fputs (_("\n\
 109 SIGNAL may be a signal name like `HUP', or a signal number like `1',\n\
 110 or the exit status of a process terminated by a signal.\n\
 111 PID is an integer; if negative it identifies a process group.\n\
 112 "), stdout);
 113       printf (USAGE_BUILTIN_WARNING, PROGRAM_NAME);
 114       emit_ancillary_info ();
 115     }
 116   exit (status);
 117 }
 118 \f
 119 /* Print a row of `kill -t' output.  NUM_WIDTH is the maximum signal
 120    number width, and SIGNUM is the signal number to print.  The
 121    maximum name width is NAME_WIDTH, and SIGNAME is the name to print.  */
 122
 123 static void
 124 print_table_row (unsigned int num_width, int signum,
 125                  unsigned int name_width, char const *signame)
 126 {
 127   char const *description = strsignal (signum);
 128   printf ("%*d %-*s %s\n", num_width, signum, name_width, signame,
 129           description ? description : "?");
 130 }
 131
 132 /* Print a list of signal names.  If TABLE, print a table.
 133    Print the names specified by ARGV if nonzero; otherwise,
 134    print all known names.  Return a suitable exit status.  */
 135
 136 static int
 137 list_signals (bool table, char *const *argv)
 138 {
 139   int signum;
 140   int status = EXIT_SUCCESS;
 141   char signame[SIG2STR_MAX];
 142
 143   if (table)
 144     {
 145       unsigned int name_width = 0;
 146
 147       /* Compute the maximum width of a signal number.  */
 148       unsigned int num_width = 1;
 149       for (signum = 1; signum <= SIGNUM_BOUND / 10; signum *= 10)
 150         num_width++;
 151
 152       /* Compute the maximum width of a signal name.  */
 153       for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 154         if (sig2str (signum, signame) == 0)
 155           {
 156             size_t len = strlen (signame);
 157             if (name_width < len)
 158               name_width = len;
 159           }
 160
 161       if (argv)
 162         for (; *argv; argv++)
 163           {
 164             signum = operand2sig (*argv, signame);
 165             if (signum < 0)
 166               status = EXIT_FAILURE;
 167             else
 168               print_table_row (num_width, signum, name_width, signame);
 169           }
 170       else
 171         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 172           if (sig2str (signum, signame) == 0)
 173             print_table_row (num_width, signum, name_width, signame);
 174     }
 175   else
 176     {
 177       if (argv)
 178         for (; *argv; argv++)
 179           {
 180             signum = operand2sig (*argv, signame);
 181             if (signum < 0)
 182               status = EXIT_FAILURE;
 183             else
 184               {
 185                 if (ISDIGIT (**argv))
 186                   puts (signame);
 187                 else
 188                   printf ("%d\n", signum);
 189               }
 190           }
 191       else
 192         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 193           if (sig2str (signum, signame) == 0)
 194             puts (signame);
 195     }
 196
 197   return status;
 198 }
 199 \f
 200 /* Send signal SIGNUM to all the processes or process groups specified
 201    by ARGV.  Return a suitable exit status.  */
 202
 203 static int
 204 send_signals (int signum, char *const *argv)
 205 {
 206   int status = EXIT_SUCCESS;
 207   char const *arg = *argv;
 208
 209   do
 210     {
 211       char *endp;
 212       intmax_t n = (errno = 0, strtoimax (arg, &endp, 10));
 213       pid_t pid = n;
 214
 215       if (errno == ERANGE || pid != n || arg == endp || *endp)
 216         {
 217           error (0, 0, _("%s: invalid process id"), arg);
 218           status = EXIT_FAILURE;
 219         }
 220       else if (kill (pid, signum) != 0)
 221         {
 222           error (0, errno, "%s", arg);
 223           status = EXIT_FAILURE;
 224         }
 225     }
 226   while ((arg = *++argv));
 227
 228   return status;
 229 }
 230 \f
 231 int
 232 main (int argc, char **argv)
 233 {
 234   int optc;
 235   bool list = false;
 236   bool table = false;
 237   int signum = -1;
 238   char signame[SIG2STR_MAX];
 239
 240   initialize_main (&argc, &argv);
 241   set_program_name (argv[0]);
 242   setlocale (LC_ALL, "");
 243   bindtextdomain (PACKAGE, LOCALEDIR);
 244   textdomain (PACKAGE);
 245
 246   atexit (close_stdout);
 247
 248   while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
 249          != -1)
 250     switch (optc)
 251       {
 252       case '0': case '1': case '2': case '3': case '4':
 253       case '5': case '6': case '7': case '8': case '9':
 254         if (optind != 2)
 255           {
 256             /* This option is actually a process-id.  */
 257             optind--;
 258             goto no_more_options;
 259           }
 260         /* Fall through.  */
 261       case 'A': case 'B': case 'C': case 'D': case 'E':
 262       case 'F': case 'G': case 'H': case 'I': case 'J':
 263       case 'K': case 'L': case 'M': case 'N': case 'O':
 264       case 'P': case 'Q': case 'R': case 'S': case 'T':
 265       case 'U': case 'V': case 'W': case 'X': case 'Y':
 266       case 'Z':
 267         if (! optarg)
 268           optarg = argv[optind - 1] + strlen (argv[optind - 1]);
 269         if (optarg != argv[optind - 1] + 2)
 270           {
 271             error (0, 0, _("invalid option -- %c"), optc);
 272             usage (EXIT_FAILURE);
 273           }
 274         optarg--;
 275         /* Fall through.  */
 276       case 'n': /* -n is not documented, but is for Bash compatibility.  */
 277       case 's':
 278         if (0 <= signum)
 279           {
 280             error (0, 0, _("%s: multiple signals specified"), optarg);
 281             usage (EXIT_FAILURE);
 282           }
 283         signum = operand2sig (optarg, signame);
 284         if (signum < 0)
 285           usage (EXIT_FAILURE);
 286         break;
 287
 288       case 't':
 289         table = true;
 290         /* Fall through.  */
 291       case 'l':
 292         if (list)
 293           {
 294             error (0, 0, _("multiple -l or -t options specified"));
 295             usage (EXIT_FAILURE);
 296           }
 297         list = true;
 298         break;
 299
 300       case_GETOPT_HELP_CHAR;
 301       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 302       default:
 303         usage (EXIT_FAILURE);
 304       }
 305  no_more_options:;
 306
 307   if (signum < 0)
 308     signum = SIGTERM;
 309   else if (list)
 310     {
 311       error (0, 0, _("cannot combine signal with -l or -t"));
 312       usage (EXIT_FAILURE);
 313     }
 314
 315   if ( ! list && argc <= optind)
 316     {
 317       error (0, 0, _("no process ID specified"));
 318       usage (EXIT_FAILURE);
 319     }
 320
 321   return (list
 322           ? list_signals (table, optind < argc ? argv + optind : NULL)
 323           : send_signals (signum, argv + optind));
 324 }