src/kill.c

   1 /* kill -- send a signal to a process
   2    Copyright (C) 2002 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 2, or (at your option)
   7    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, write to the Free Software Foundation,
  16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 /* Written by Paul Eggert.  */
  19
  20 #include <config.h>
  21 #include <stdio.h>
  22 #include <getopt.h>
  23 #include <sys/types.h>
  24 #include <signal.h>
  25
  26 #if HAVE_SYS_WAIT_H
  27 # include <sys/wait.h>
  28 #endif
  29 #ifndef WIFSIGNALED
  30 # define WIFSIGNALED(s) (((s) & 0xFFFF) - 1 < (unsigned int) 0xFF)
  31 #endif
  32 #ifndef WTERMSIG
  33 # define WTERMSIG(s) ((s) & 0x7F)
  34 #endif
  35
  36 #include "system.h"
  37 #include "closeout.h"
  38 #include "error.h"
  39 #include "sig2str.h"
  40
  41 /* The official name of this program (e.g., no `g' prefix).  */
  42 #define PROGRAM_NAME "kill"
  43
  44 #define AUTHORS "Paul Eggert"
  45 \f
  46 #if ! (HAVE_DECL_STRTOIMAX || defined strtoimax)
  47 intmax_t strtoimax ();
  48 #endif
  49
  50 #if ! (HAVE_DECL_STRSIGNAL || defined strsignal)
  51 # if ! (HAVE_DECL_SYS_SIGLIST || defined sys_siglist)
  52 #  if HAVE_DECL__SYS_SIGLIST || defined _sys_siglist
  53 #   define sys_siglist _sys_siglist
  54 #  endif
  55 # endif
  56 # if HAVE_DECL_SYS_SIGLIST || defined sys_siglist
  57 #  define strsignal(signum) (0 <= (signum) && (signum) <= SIGNUM_BOUND \
  58                              ? sys_siglist[signum] \
  59                              : 0)
  60 # endif
  61 # ifndef strsignal
  62 #  define strsignal(signum) 0
  63 # endif
  64 #endif
  65 \f
  66 /* The name this program was run with, for error messages.  */
  67 char *program_name;
  68
  69 static char const short_options[] =
  70   "0::1::2::3::4::5::6::7::8::9::"
  71   "A::B::C::D::E::F::G::H::I::J::K::L::M::"
  72   "N::O::P::Q::R::S::T::U::V::W::X::Y::Z::"
  73   "ln:s:t";
  74
  75 static struct option const long_options[] =
  76 {
  77   {"list", no_argument, NULL, 'l'},
  78   {"signal", required_argument, NULL, 's'},
  79   {"table", no_argument, NULL, 't'},
  80   {GETOPT_HELP_OPTION_DECL},
  81   {GETOPT_VERSION_OPTION_DECL},
  82   {NULL, 0, NULL, 0}
  83 };
  84
  85 void
  86 usage (int status)
  87 {
  88   if (status != 0)
  89     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  90              program_name);
  91   else
  92     {
  93       printf (_("\
  94 Usage: %s [-s SIGNAL | -SIGNAL] PID...\n\
  95   or:  %s -l [SIGNAL]...\n\
  96   or:  %s -t [SIGNAL]...\n\
  97 "),
  98               program_name, program_name, program_name);
  99       fputs (_("\
 100 Send signals to processes, or list signals.\n\
 101 \n\
 102 "), stdout);
 103       fputs (_("\
 104 Mandatory arguments to long options are mandatory for short options too.\n\
 105 "), stdout);
 106       fputs (_("\
 107   -s, --signal=SIGNAL, -SIGNAL\n\
 108                    specify the name or number of the signal to be sent\n\
 109   -l, --list       list signal names, or convert signal names to/from numbers\n\
 110   -t, --table      print a table of signal information\n\
 111 "), stdout);
 112       fputs (HELP_OPTION_DESCRIPTION, stdout);
 113       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 114       fputs (_("\n\
 115 SIGNAL may be a signal name like `HUP', or a signal number like `1',\n\
 116 or an exit status of a process terminated by a signal.\n\
 117 PID is an integer; if negative it identifies a process group.\n\
 118 "), stdout);
 119       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 120     }
 121   exit (status);
 122 }
 123 \f
 124 /* Convert OPERAND to a signal number with printable representation SIGNAME.
 125    Return the signal number, or -1 if unsuccessful.  */
 126
 127 static int
 128 operand2sig (char const *operand, char *signame)
 129 {
 130   int signum;
 131
 132   if (ISDIGIT (*operand))
 133     {
 134       char *endp;
 135       long int l = (errno = 0, strtol (operand, &endp, 10));
 136       int i = l;
 137       signum = (operand == endp || *endp || errno || i != l ? -1
 138                 : WIFSIGNALED (i) ? WTERMSIG (i)
 139                 : i);
 140     }
 141   else
 142     {
 143       /* Convert signal to upper case in the C locale, not in the
 144          current locale.  Don't assume ASCII; it might be EBCDIC.  */
 145       char *upcased = xstrdup (operand);
 146       char *p;
 147       for (p = upcased; *p; p++)
 148         if (strchr ("abcdefghijklmnopqrstuvwxyz", *p))
 149           *p += 'A' - 'a';
 150
 151       /* Look for the signal name, possibly prefixed by "SIG",
 152          and possibly lowercased.  */
 153       if (! (str2sig (upcased, &signum) == 0
 154              || (upcased[0] == 'S' && upcased[1] == 'I' && upcased[2] == 'G'
 155                  && str2sig (upcased + 3, &signum) == 0)))
 156         signum = -1;
 157
 158       free (upcased);
 159     }
 160
 161   if (signum < 0 || sig2str (signum, signame) != 0)
 162     {
 163       error (0, 0, _("%s: invalid signal"), operand);
 164       return -1;
 165     }
 166
 167   return signum;
 168 }
 169 \f
 170 /* Print a row of `kill -t' output.  NUM_WIDTH is the maximum signal
 171    number width, and SIGNUM is the signal number to print.  The
 172    maximum name width is NAME_WIDTH, and SIGNAME is the name to print.  */
 173
 174 static void
 175 print_table_row (int num_width, int signum,
 176                  int name_width, char const *signame)
 177 {
 178   char const *description = strsignal (signum);
 179   printf ("%*d %-*s %s\n", num_width, signum, name_width, signame,
 180           description ? description : "?");
 181 }
 182
 183 /* Print a list of signal names.  If TABLE, print a table.
 184    Print the names specified by ARGV if nonzero; otherwise,
 185    print all known names.  Return a suitable exit status.  */
 186
 187 static int
 188 list_signals (bool table, char *const *argv)
 189 {
 190   int signum;
 191   int status = EXIT_SUCCESS;
 192   char signame[SIG2STR_MAX];
 193
 194   if (table)
 195     {
 196       int name_width = 0;
 197
 198       /* Compute the maximum width of a signal number.  */
 199       int num_width = 1;
 200       for (signum = 1; signum <= SIGNUM_BOUND / 10; signum *= 10)
 201         num_width++;
 202
 203       /* Compute the maximum width of a signal name.  */
 204       for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 205         if (sig2str (signum, signame) == 0)
 206           {
 207             size_t len = strlen (signame);
 208             if (name_width < len)
 209               name_width = len;
 210           }
 211
 212       if (argv)
 213         for (; *argv; argv++)
 214           {
 215             signum = operand2sig (*argv, signame);
 216             if (signum < 0)
 217               status = EXIT_FAILURE;
 218             else
 219               print_table_row (num_width, signum, name_width, signame);
 220           }
 221       else
 222         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 223           if (sig2str (signum, signame) == 0)
 224             print_table_row (num_width, signum, name_width, signame);
 225     }
 226   else
 227     {
 228       if (argv)
 229         for (; *argv; argv++)
 230           {
 231             signum = operand2sig (*argv, signame);
 232             if (signum < 0)
 233               status = EXIT_FAILURE;
 234             else
 235               {
 236                 if (ISDIGIT (**argv))
 237                   puts (signame);
 238                 else
 239                   printf ("%d\n", signum);
 240               }
 241           }
 242       else
 243         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 244           if (sig2str (signum, signame) == 0)
 245             puts (signame);
 246     }
 247
 248   return status;
 249 }
 250 \f
 251 /* Send signal SIGNUM to all the processes or process groups specified
 252    by ARGV.  Return a suitable exit status.  */
 253
 254 static int
 255 send_signals (int signum, char *const *argv)
 256 {
 257   int status = EXIT_SUCCESS;
 258   char const *arg = *argv;
 259
 260   if (! arg)
 261     {
 262       error (0, 0, _("missing operand after `%s'"), argv[-1]);
 263       usage (EXIT_FAILURE);
 264     }
 265
 266   do
 267     {
 268       char *endp;
 269       intmax_t n = (errno = 0, strtoimax (arg, &endp, 10));
 270       pid_t pid = n;
 271
 272       if (errno == ERANGE || pid != n || arg == endp || *endp)
 273         {
 274           error (0, 0, _("%s: invalid process id"), arg);
 275           status = EXIT_FAILURE;
 276         }
 277       else if (kill (pid, signum) != 0)
 278         {
 279           error (0, errno, "%s", arg);
 280           status = EXIT_FAILURE;
 281         }
 282     }
 283   while ((arg = *++argv));
 284
 285   return status;
 286 }
 287 \f
 288 int
 289 main (int argc, char **argv)
 290 {
 291   int optc;
 292   bool list = false;
 293   bool table = false;
 294   int signum = -1;
 295   char signame[SIG2STR_MAX];
 296
 297   program_name = argv[0];
 298   setlocale (LC_ALL, "");
 299   bindtextdomain (PACKAGE, LOCALEDIR);
 300   textdomain (PACKAGE);
 301
 302   atexit (close_stdout);
 303
 304   while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
 305          != -1)
 306     switch (optc)
 307       {
 308       case '0': case '1': case '2': case '3': case '4':
 309       case '5': case '6': case '7': case '8': case '9':
 310         if (optind != 2)
 311           {
 312             /* This option is actually a process-id.  */
 313             optind--;
 314             goto no_more_options;
 315           }
 316         /* Fall through.  */
 317       case 'A': case 'B': case 'C': case 'D': case 'E':
 318       case 'F': case 'G': case 'H': case 'I': case 'J':
 319       case 'K': case 'L': case 'M': case 'N': case 'O':
 320       case 'P': case 'Q': case 'R': case 'S': case 'T':
 321       case 'U': case 'V': case 'W': case 'X': case 'Y':
 322       case 'Z':
 323         if (! optarg)
 324           optarg = argv[optind - 1] + strlen (argv[optind - 1]);
 325         if (optarg != argv[optind - 1] + 2)
 326           {
 327             error (0, 0, _("invalid option -- %c"), optc);
 328             usage (EXIT_FAILURE);
 329           }
 330         optarg--;
 331         /* Fall through.  */
 332       case 'n': /* -n is not documented, but is for Bash compatibility.  */
 333       case 's':
 334         if (0 <= signum)
 335           {
 336             error (0, 0, _("%s: multiple signals specified"), optarg);
 337             usage (EXIT_FAILURE);
 338           }
 339         signum = operand2sig (optarg, signame);
 340         if (signum < 0)
 341           usage (EXIT_FAILURE);
 342         break;
 343
 344       case 't':
 345         table = true;
 346         /* Fall through.  */
 347       case 'l':
 348         if (list)
 349           {
 350             error (0, 0, _("multiple -l or -t options specified"));
 351             usage (EXIT_FAILURE);
 352           }
 353         list = true;
 354         break;
 355
 356       case_GETOPT_HELP_CHAR;
 357       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 358       default:
 359         usage (EXIT_FAILURE);
 360       }
 361  no_more_options:;
 362
 363   if (signum < 0)
 364     signum = SIGTERM;
 365   else if (list)
 366     {
 367       error (0, 0, _("cannot combine signal with -l or -t"));
 368       usage (EXIT_FAILURE);
 369     }
 370
 371   return (list
 372           ? list_signals (table, optind == argc ? NULL : argv + optind)
 373           : send_signals (signum, argv + optind));
 374 }