src/kill.c

   1 /* kill -- send a signal to a process
   2    Copyright (C) 2002, 2003, 2004, 2005 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
  39 /* The official name of this program (e.g., no `g' prefix).  */
  40 #define PROGRAM_NAME "kill"
  41
  42 #define AUTHORS "Paul Eggert"
  43 \f
  44 #if ! (HAVE_DECL_STRSIGNAL || defined strsignal)
  45 # if ! (HAVE_DECL_SYS_SIGLIST || defined sys_siglist)
  46 #  if HAVE_DECL__SYS_SIGLIST || defined _sys_siglist
  47 #   define sys_siglist _sys_siglist
  48 #  elif HAVE_DECL___SYS_SIGLIST || defined __sys_siglist
  49 #   define sys_siglist __sys_siglist
  50 #  endif
  51 # endif
  52 # if HAVE_DECL_SYS_SIGLIST || defined sys_siglist
  53 #  define strsignal(signum) (0 <= (signum) && (signum) <= SIGNUM_BOUND \
  54                              ? sys_siglist[signum] \
  55                              : 0)
  56 # endif
  57 # ifndef strsignal
  58 #  define strsignal(signum) 0
  59 # endif
  60 #endif
  61 \f
  62 /* The name this program was run with, for error messages.  */
  63 char *program_name;
  64
  65 static char const short_options[] =
  66   "0::1::2::3::4::5::6::7::8::9::"
  67   "A::B::C::D::E::F::G::H::I::J::K::L::M::"
  68   "N::O::P::Q::R::S::T::U::V::W::X::Y::Z::"
  69   "ln:s:t";
  70
  71 static struct option const long_options[] =
  72 {
  73   {"list", no_argument, NULL, 'l'},
  74   {"signal", required_argument, NULL, 's'},
  75   {"table", no_argument, NULL, 't'},
  76   {GETOPT_HELP_OPTION_DECL},
  77   {GETOPT_VERSION_OPTION_DECL},
  78   {NULL, 0, NULL, 0}
  79 };
  80
  81 void
  82 usage (int status)
  83 {
  84   if (status != EXIT_SUCCESS)
  85     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  86              program_name);
  87   else
  88     {
  89       printf (_("\
  90 Usage: %s [-s SIGNAL | -SIGNAL] PID...\n\
  91   or:  %s -l [SIGNAL]...\n\
  92   or:  %s -t [SIGNAL]...\n\
  93 "),
  94               program_name, program_name, program_name);
  95       fputs (_("\
  96 Send signals to processes, or list signals.\n\
  97 \n\
  98 "), stdout);
  99       fputs (_("\
 100 Mandatory arguments to long options are mandatory for short options too.\n\
 101 "), stdout);
 102       fputs (_("\
 103   -s, --signal=SIGNAL, -SIGNAL\n\
 104                    specify the name or number of the signal to be sent\n\
 105   -l, --list       list signal names, or convert signal names to/from numbers\n\
 106   -t, --table      print a table of signal information\n\
 107 "), stdout);
 108       fputs (HELP_OPTION_DESCRIPTION, stdout);
 109       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 110       fputs (_("\n\
 111 SIGNAL may be a signal name like `HUP', or a signal number like `1',\n\
 112 or an exit status of a process terminated by a signal.\n\
 113 PID is an integer; if negative it identifies a process group.\n\
 114 "), stdout);
 115       printf (USAGE_BUILTIN_WARNING, PROGRAM_NAME);
 116       emit_bug_reporting_address ();
 117     }
 118   exit (status);
 119 }
 120 \f
 121 /* Convert OPERAND to a signal number with printable representation SIGNAME.
 122    Return the signal number, or -1 if unsuccessful.  */
 123
 124 static int
 125 operand2sig (char const *operand, char *signame)
 126 {
 127   int signum;
 128
 129   if (ISDIGIT (*operand))
 130     {
 131       char *endp;
 132       long int l = (errno = 0, strtol (operand, &endp, 10));
 133       int i = l;
 134       signum = (operand == endp || *endp || errno || i != l ? -1
 135                 : WIFSIGNALED (i) ? WTERMSIG (i)
 136                 : i);
 137     }
 138   else
 139     {
 140       /* Convert signal to upper case in the C locale, not in the
 141          current locale.  Don't assume ASCII; it might be EBCDIC.  */
 142       char *upcased = xstrdup (operand);
 143       char *p;
 144       for (p = upcased; *p; p++)
 145         if (strchr ("abcdefghijklmnopqrstuvwxyz", *p))
 146           *p += 'A' - 'a';
 147
 148       /* Look for the signal name, possibly prefixed by "SIG",
 149          and possibly lowercased.  */
 150       if (! (str2sig (upcased, &signum) == 0
 151              || (upcased[0] == 'S' && upcased[1] == 'I' && upcased[2] == 'G'
 152                  && str2sig (upcased + 3, &signum) == 0)))
 153         signum = -1;
 154
 155       free (upcased);
 156     }
 157
 158   if (signum < 0 || sig2str (signum, signame) != 0)
 159     {
 160       error (0, 0, _("%s: invalid signal"), operand);
 161       return -1;
 162     }
 163
 164   return signum;
 165 }
 166 \f
 167 /* Print a row of `kill -t' output.  NUM_WIDTH is the maximum signal
 168    number width, and SIGNUM is the signal number to print.  The
 169    maximum name width is NAME_WIDTH, and SIGNAME is the name to print.  */
 170
 171 static void
 172 print_table_row (unsigned int num_width, int signum,
 173                  unsigned int name_width, char const *signame)
 174 {
 175   char const *description = strsignal (signum);
 176   printf ("%*d %-*s %s\n", num_width, signum, name_width, signame,
 177           description ? description : "?");
 178 }
 179
 180 /* Print a list of signal names.  If TABLE, print a table.
 181    Print the names specified by ARGV if nonzero; otherwise,
 182    print all known names.  Return a suitable exit status.  */
 183
 184 static int
 185 list_signals (bool table, char *const *argv)
 186 {
 187   int signum;
 188   int status = EXIT_SUCCESS;
 189   char signame[SIG2STR_MAX];
 190
 191   if (table)
 192     {
 193       unsigned int name_width = 0;
 194
 195       /* Compute the maximum width of a signal number.  */
 196       unsigned int num_width = 1;
 197       for (signum = 1; signum <= SIGNUM_BOUND / 10; signum *= 10)
 198         num_width++;
 199
 200       /* Compute the maximum width of a signal name.  */
 201       for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 202         if (sig2str (signum, signame) == 0)
 203           {
 204             size_t len = strlen (signame);
 205             if (name_width < len)
 206               name_width = len;
 207           }
 208
 209       if (argv)
 210         for (; *argv; argv++)
 211           {
 212             signum = operand2sig (*argv, signame);
 213             if (signum < 0)
 214               status = EXIT_FAILURE;
 215             else
 216               print_table_row (num_width, signum, name_width, signame);
 217           }
 218       else
 219         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 220           if (sig2str (signum, signame) == 0)
 221             print_table_row (num_width, signum, name_width, signame);
 222     }
 223   else
 224     {
 225       if (argv)
 226         for (; *argv; argv++)
 227           {
 228             signum = operand2sig (*argv, signame);
 229             if (signum < 0)
 230               status = EXIT_FAILURE;
 231             else
 232               {
 233                 if (ISDIGIT (**argv))
 234                   puts (signame);
 235                 else
 236                   printf ("%d\n", signum);
 237               }
 238           }
 239       else
 240         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 241           if (sig2str (signum, signame) == 0)
 242             puts (signame);
 243     }
 244
 245   return status;
 246 }
 247 \f
 248 /* Send signal SIGNUM to all the processes or process groups specified
 249    by ARGV.  Return a suitable exit status.  */
 250
 251 static int
 252 send_signals (int signum, char *const *argv)
 253 {
 254   int status = EXIT_SUCCESS;
 255   char const *arg = *argv;
 256
 257   do
 258     {
 259       char *endp;
 260       intmax_t n = (errno = 0, strtoimax (arg, &endp, 10));
 261       pid_t pid = n;
 262
 263       if (errno == ERANGE || pid != n || arg == endp || *endp)
 264         {
 265           error (0, 0, _("%s: invalid process id"), arg);
 266           status = EXIT_FAILURE;
 267         }
 268       else if (kill (pid, signum) != 0)
 269         {
 270           error (0, errno, "%s", arg);
 271           status = EXIT_FAILURE;
 272         }
 273     }
 274   while ((arg = *++argv));
 275
 276   return status;
 277 }
 278 \f
 279 int
 280 main (int argc, char **argv)
 281 {
 282   int optc;
 283   bool list = false;
 284   bool table = false;
 285   int signum = -1;
 286   char signame[SIG2STR_MAX];
 287
 288   initialize_main (&argc, &argv);
 289   program_name = argv[0];
 290   setlocale (LC_ALL, "");
 291   bindtextdomain (PACKAGE, LOCALEDIR);
 292   textdomain (PACKAGE);
 293
 294   atexit (close_stdout);
 295
 296   while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
 297          != -1)
 298     switch (optc)
 299       {
 300       case '0': case '1': case '2': case '3': case '4':
 301       case '5': case '6': case '7': case '8': case '9':
 302         if (optind != 2)
 303           {
 304             /* This option is actually a process-id.  */
 305             optind--;
 306             goto no_more_options;
 307           }
 308         /* Fall through.  */
 309       case 'A': case 'B': case 'C': case 'D': case 'E':
 310       case 'F': case 'G': case 'H': case 'I': case 'J':
 311       case 'K': case 'L': case 'M': case 'N': case 'O':
 312       case 'P': case 'Q': case 'R': case 'S': case 'T':
 313       case 'U': case 'V': case 'W': case 'X': case 'Y':
 314       case 'Z':
 315         if (! optarg)
 316           optarg = argv[optind - 1] + strlen (argv[optind - 1]);
 317         if (optarg != argv[optind - 1] + 2)
 318           {
 319             error (0, 0, _("invalid option -- %c"), optc);
 320             usage (EXIT_FAILURE);
 321           }
 322         optarg--;
 323         /* Fall through.  */
 324       case 'n': /* -n is not documented, but is for Bash compatibility.  */
 325       case 's':
 326         if (0 <= signum)
 327           {
 328             error (0, 0, _("%s: multiple signals specified"), optarg);
 329             usage (EXIT_FAILURE);
 330           }
 331         signum = operand2sig (optarg, signame);
 332         if (signum < 0)
 333           usage (EXIT_FAILURE);
 334         break;
 335
 336       case 't':
 337         table = true;
 338         /* Fall through.  */
 339       case 'l':
 340         if (list)
 341           {
 342             error (0, 0, _("multiple -l or -t options specified"));
 343             usage (EXIT_FAILURE);
 344           }
 345         list = true;
 346         break;
 347
 348       case_GETOPT_HELP_CHAR;
 349       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 350       default:
 351         usage (EXIT_FAILURE);
 352       }
 353  no_more_options:;
 354
 355   if (signum < 0)
 356     signum = SIGTERM;
 357   else if (list)
 358     {
 359       error (0, 0, _("cannot combine signal with -l or -t"));
 360       usage (EXIT_FAILURE);
 361     }
 362
 363   if ( ! list && argc <= optind)
 364     {
 365       error (0, 0, _("no process ID specified"));
 366       usage (EXIT_FAILURE);
 367     }
 368
 369   return (list
 370           ? list_signals (table, optind < argc ? argv + optind : NULL)
 371           : send_signals (signum, argv + optind));
 372 }