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 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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 "error.h"
  38 #include "sig2str.h"
  39
  40 /* The official name of this program (e.g., no `g' prefix).  */
  41 #define PROGRAM_NAME "kill"
  42
  43 #define AUTHORS "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 /* The name this program was run with, for error messages.  */
  64 char *program_name;
  65
  66 static char const short_options[] =
  67   "0::1::2::3::4::5::6::7::8::9::"
  68   "A::B::C::D::E::F::G::H::I::J::K::L::M::"
  69   "N::O::P::Q::R::S::T::U::V::W::X::Y::Z::"
  70   "ln:s:t";
  71
  72 static struct option const long_options[] =
  73 {
  74   {"list", no_argument, NULL, 'l'},
  75   {"signal", required_argument, NULL, 's'},
  76   {"table", no_argument, NULL, 't'},
  77   {GETOPT_HELP_OPTION_DECL},
  78   {GETOPT_VERSION_OPTION_DECL},
  79   {NULL, 0, NULL, 0}
  80 };
  81
  82 void
  83 usage (int status)
  84 {
  85   if (status != EXIT_SUCCESS)
  86     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  87              program_name);
  88   else
  89     {
  90       printf (_("\
  91 Usage: %s [-s SIGNAL | -SIGNAL] PID...\n\
  92   or:  %s -l [SIGNAL]...\n\
  93   or:  %s -t [SIGNAL]...\n\
  94 "),
  95               program_name, program_name, program_name);
  96       fputs (_("\
  97 Send signals to processes, or list signals.\n\
  98 \n\
  99 "), stdout);
 100       fputs (_("\
 101 Mandatory arguments to long options are mandatory for short options too.\n\
 102 "), stdout);
 103       fputs (_("\
 104   -s, --signal=SIGNAL, -SIGNAL\n\
 105                    specify the name or number of the signal to be sent\n\
 106   -l, --list       list signal names, or convert signal names to/from numbers\n\
 107   -t, --table      print a table of signal information\n\
 108 "), stdout);
 109       fputs (HELP_OPTION_DESCRIPTION, stdout);
 110       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 111       fputs (_("\n\
 112 SIGNAL may be a signal name like `HUP', or a signal number like `1',\n\
 113 or an exit status of a process terminated by a signal.\n\
 114 PID is an integer; if negative it identifies a process group.\n\
 115 "), stdout);
 116       printf (USAGE_BUILTIN_WARNING, PROGRAM_NAME);
 117       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 118     }
 119   exit (status);
 120 }
 121 \f
 122 /* Convert OPERAND to a signal number with printable representation SIGNAME.
 123    Return the signal number, or -1 if unsuccessful.  */
 124
 125 static int
 126 operand2sig (char const *operand, char *signame)
 127 {
 128   int signum;
 129
 130   if (ISDIGIT (*operand))
 131     {
 132       char *endp;
 133       long int l = (errno = 0, strtol (operand, &endp, 10));
 134       int i = l;
 135       signum = (operand == endp || *endp || errno || i != l ? -1
 136                 : WIFSIGNALED (i) ? WTERMSIG (i)
 137                 : i);
 138     }
 139   else
 140     {
 141       /* Convert signal to upper case in the C locale, not in the
 142          current locale.  Don't assume ASCII; it might be EBCDIC.  */
 143       char *upcased = xstrdup (operand);
 144       char *p;
 145       for (p = upcased; *p; p++)
 146         if (strchr ("abcdefghijklmnopqrstuvwxyz", *p))
 147           *p += 'A' - 'a';
 148
 149       /* Look for the signal name, possibly prefixed by "SIG",
 150          and possibly lowercased.  */
 151       if (! (str2sig (upcased, &signum) == 0
 152              || (upcased[0] == 'S' && upcased[1] == 'I' && upcased[2] == 'G'
 153                  && str2sig (upcased + 3, &signum) == 0)))
 154         signum = -1;
 155
 156       free (upcased);
 157     }
 158
 159   if (signum < 0 || sig2str (signum, signame) != 0)
 160     {
 161       error (0, 0, _("%s: invalid signal"), operand);
 162       return -1;
 163     }
 164
 165   return signum;
 166 }
 167 \f
 168 /* Print a row of `kill -t' output.  NUM_WIDTH is the maximum signal
 169    number width, and SIGNUM is the signal number to print.  The
 170    maximum name width is NAME_WIDTH, and SIGNAME is the name to print.  */
 171
 172 static void
 173 print_table_row (unsigned int num_width, int signum,
 174                  unsigned int name_width, char const *signame)
 175 {
 176   char const *description = strsignal (signum);
 177   printf ("%*d %-*s %s\n", num_width, signum, name_width, signame,
 178           description ? description : "?");
 179 }
 180
 181 /* Print a list of signal names.  If TABLE, print a table.
 182    Print the names specified by ARGV if nonzero; otherwise,
 183    print all known names.  Return a suitable exit status.  */
 184
 185 static int
 186 list_signals (bool table, char *const *argv)
 187 {
 188   int signum;
 189   int status = EXIT_SUCCESS;
 190   char signame[SIG2STR_MAX];
 191
 192   if (table)
 193     {
 194       unsigned int name_width = 0;
 195
 196       /* Compute the maximum width of a signal number.  */
 197       unsigned int num_width = 1;
 198       for (signum = 1; signum <= SIGNUM_BOUND / 10; signum *= 10)
 199         num_width++;
 200
 201       /* Compute the maximum width of a signal name.  */
 202       for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 203         if (sig2str (signum, signame) == 0)
 204           {
 205             size_t len = strlen (signame);
 206             if (name_width < len)
 207               name_width = len;
 208           }
 209
 210       if (argv)
 211         for (; *argv; argv++)
 212           {
 213             signum = operand2sig (*argv, signame);
 214             if (signum < 0)
 215               status = EXIT_FAILURE;
 216             else
 217               print_table_row (num_width, signum, name_width, signame);
 218           }
 219       else
 220         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 221           if (sig2str (signum, signame) == 0)
 222             print_table_row (num_width, signum, name_width, signame);
 223     }
 224   else
 225     {
 226       if (argv)
 227         for (; *argv; argv++)
 228           {
 229             signum = operand2sig (*argv, signame);
 230             if (signum < 0)
 231               status = EXIT_FAILURE;
 232             else
 233               {
 234                 if (ISDIGIT (**argv))
 235                   puts (signame);
 236                 else
 237                   printf ("%d\n", signum);
 238               }
 239           }
 240       else
 241         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 242           if (sig2str (signum, signame) == 0)
 243             puts (signame);
 244     }
 245
 246   return status;
 247 }
 248 \f
 249 /* Send signal SIGNUM to all the processes or process groups specified
 250    by ARGV.  Return a suitable exit status.  */
 251
 252 static int
 253 send_signals (int signum, char *const *argv)
 254 {
 255   int status = EXIT_SUCCESS;
 256   char const *arg = *argv;
 257
 258   do
 259     {
 260       char *endp;
 261       intmax_t n = (errno = 0, strtoimax (arg, &endp, 10));
 262       pid_t pid = n;
 263
 264       if (errno == ERANGE || pid != n || arg == endp || *endp)
 265         {
 266           error (0, 0, _("%s: invalid process id"), arg);
 267           status = EXIT_FAILURE;
 268         }
 269       else if (kill (pid, signum) != 0)
 270         {
 271           error (0, errno, "%s", arg);
 272           status = EXIT_FAILURE;
 273         }
 274     }
 275   while ((arg = *++argv));
 276
 277   return status;
 278 }
 279 \f
 280 int
 281 main (int argc, char **argv)
 282 {
 283   int optc;
 284   bool list = false;
 285   bool table = false;
 286   int signum = -1;
 287   char signame[SIG2STR_MAX];
 288
 289   initialize_main (&argc, &argv);
 290   program_name = argv[0];
 291   setlocale (LC_ALL, "");
 292   bindtextdomain (PACKAGE, LOCALEDIR);
 293   textdomain (PACKAGE);
 294
 295   atexit (close_stdout);
 296
 297   while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
 298          != -1)
 299     switch (optc)
 300       {
 301       case '0': case '1': case '2': case '3': case '4':
 302       case '5': case '6': case '7': case '8': case '9':
 303         if (optind != 2)
 304           {
 305             /* This option is actually a process-id.  */
 306             optind--;
 307             goto no_more_options;
 308           }
 309         /* Fall through.  */
 310       case 'A': case 'B': case 'C': case 'D': case 'E':
 311       case 'F': case 'G': case 'H': case 'I': case 'J':
 312       case 'K': case 'L': case 'M': case 'N': case 'O':
 313       case 'P': case 'Q': case 'R': case 'S': case 'T':
 314       case 'U': case 'V': case 'W': case 'X': case 'Y':
 315       case 'Z':
 316         if (! optarg)
 317           optarg = argv[optind - 1] + strlen (argv[optind - 1]);
 318         if (optarg != argv[optind - 1] + 2)
 319           {
 320             error (0, 0, _("invalid option -- %c"), optc);
 321             usage (EXIT_FAILURE);
 322           }
 323         optarg--;
 324         /* Fall through.  */
 325       case 'n': /* -n is not documented, but is for Bash compatibility.  */
 326       case 's':
 327         if (0 <= signum)
 328           {
 329             error (0, 0, _("%s: multiple signals specified"), optarg);
 330             usage (EXIT_FAILURE);
 331           }
 332         signum = operand2sig (optarg, signame);
 333         if (signum < 0)
 334           usage (EXIT_FAILURE);
 335         break;
 336
 337       case 't':
 338         table = true;
 339         /* Fall through.  */
 340       case 'l':
 341         if (list)
 342           {
 343             error (0, 0, _("multiple -l or -t options specified"));
 344             usage (EXIT_FAILURE);
 345           }
 346         list = true;
 347         break;
 348
 349       case_GETOPT_HELP_CHAR;
 350       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 351       default:
 352         usage (EXIT_FAILURE);
 353       }
 354  no_more_options:;
 355
 356   if (signum < 0)
 357     signum = SIGTERM;
 358   else if (list)
 359     {
 360       error (0, 0, _("cannot combine signal with -l or -t"));
 361       usage (EXIT_FAILURE);
 362     }
 363
 364   if ( ! list && argc <= optind)
 365     {
 366       error (0, 0, _("no process ID specified"));
 367       usage (EXIT_FAILURE);
 368     }
 369
 370   return (list
 371           ? list_signals (table, optind < argc ? argv + optind : NULL)
 372           : send_signals (signum, argv + optind));
 373 }