src/kill.c

   1 /* kill -- send a signal to a process
   2    Copyright (C) 2002, 2003, 2004 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 "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_STRTOIMAX || defined strtoimax)
  46 intmax_t strtoimax ();
  47 #endif
  48
  49 #if ! (HAVE_DECL_STRSIGNAL || defined strsignal)
  50 # if ! (HAVE_DECL_SYS_SIGLIST || defined sys_siglist)
  51 #  if HAVE_DECL__SYS_SIGLIST || defined _sys_siglist
  52 #   define sys_siglist _sys_siglist
  53 #  elif HAVE_DECL___SYS_SIGLIST || defined __sys_siglist
  54 #   define sys_siglist __sys_siglist
  55 #  endif
  56 # endif
  57 # if HAVE_DECL_SYS_SIGLIST || defined sys_siglist
  58 #  define strsignal(signum) (0 <= (signum) && (signum) <= SIGNUM_BOUND \
  59                              ? sys_siglist[signum] \
  60                              : 0)
  61 # endif
  62 # ifndef strsignal
  63 #  define strsignal(signum) 0
  64 # endif
  65 #endif
  66 \f
  67 /* The name this program was run with, for error messages.  */
  68 char *program_name;
  69
  70 static char const short_options[] =
  71   "0::1::2::3::4::5::6::7::8::9::"
  72   "A::B::C::D::E::F::G::H::I::J::K::L::M::"
  73   "N::O::P::Q::R::S::T::U::V::W::X::Y::Z::"
  74   "ln:s:t";
  75
  76 static struct option const long_options[] =
  77 {
  78   {"list", no_argument, NULL, 'l'},
  79   {"signal", required_argument, NULL, 's'},
  80   {"table", no_argument, NULL, 't'},
  81   {GETOPT_HELP_OPTION_DECL},
  82   {GETOPT_VERSION_OPTION_DECL},
  83   {NULL, 0, NULL, 0}
  84 };
  85
  86 void
  87 usage (int status)
  88 {
  89   if (status != EXIT_SUCCESS)
  90     fprintf (stderr, _("Try `%s --help' for more information.\n"),
  91              program_name);
  92   else
  93     {
  94       printf (_("\
  95 Usage: %s [-s SIGNAL | -SIGNAL] PID...\n\
  96   or:  %s -l [SIGNAL]...\n\
  97   or:  %s -t [SIGNAL]...\n\
  98 "),
  99               program_name, program_name, program_name);
 100       fputs (_("\
 101 Send signals to processes, or list signals.\n\
 102 \n\
 103 "), stdout);
 104       fputs (_("\
 105 Mandatory arguments to long options are mandatory for short options too.\n\
 106 "), stdout);
 107       fputs (_("\
 108   -s, --signal=SIGNAL, -SIGNAL\n\
 109                    specify the name or number of the signal to be sent\n\
 110   -l, --list       list signal names, or convert signal names to/from numbers\n\
 111   -t, --table      print a table of signal information\n\
 112 "), stdout);
 113       fputs (HELP_OPTION_DESCRIPTION, stdout);
 114       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 115       fputs (_("\n\
 116 SIGNAL may be a signal name like `HUP', or a signal number like `1',\n\
 117 or an exit status of a process terminated by a signal.\n\
 118 PID is an integer; if negative it identifies a process group.\n\
 119 "), stdout);
 120       printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
 121     }
 122   exit (status);
 123 }
 124 \f
 125 /* Convert OPERAND to a signal number with printable representation SIGNAME.
 126    Return the signal number, or -1 if unsuccessful.  */
 127
 128 static int
 129 operand2sig (char const *operand, char *signame)
 130 {
 131   int signum;
 132
 133   if (ISDIGIT (*operand))
 134     {
 135       char *endp;
 136       long int l = (errno = 0, strtol (operand, &endp, 10));
 137       int i = l;
 138       signum = (operand == endp || *endp || errno || i != l ? -1
 139                 : WIFSIGNALED (i) ? WTERMSIG (i)
 140                 : i);
 141     }
 142   else
 143     {
 144       /* Convert signal to upper case in the C locale, not in the
 145          current locale.  Don't assume ASCII; it might be EBCDIC.  */
 146       char *upcased = xstrdup (operand);
 147       char *p;
 148       for (p = upcased; *p; p++)
 149         if (strchr ("abcdefghijklmnopqrstuvwxyz", *p))
 150           *p += 'A' - 'a';
 151
 152       /* Look for the signal name, possibly prefixed by "SIG",
 153          and possibly lowercased.  */
 154       if (! (str2sig (upcased, &signum) == 0
 155              || (upcased[0] == 'S' && upcased[1] == 'I' && upcased[2] == 'G'
 156                  && str2sig (upcased + 3, &signum) == 0)))
 157         signum = -1;
 158
 159       free (upcased);
 160     }
 161
 162   if (signum < 0 || sig2str (signum, signame) != 0)
 163     {
 164       error (0, 0, _("%s: invalid signal"), operand);
 165       return -1;
 166     }
 167
 168   return signum;
 169 }
 170 \f
 171 /* Print a row of `kill -t' output.  NUM_WIDTH is the maximum signal
 172    number width, and SIGNUM is the signal number to print.  The
 173    maximum name width is NAME_WIDTH, and SIGNAME is the name to print.  */
 174
 175 static void
 176 print_table_row (unsigned int num_width, int signum,
 177                  unsigned int name_width, char const *signame)
 178 {
 179   char const *description = strsignal (signum);
 180   printf ("%*d %-*s %s\n", num_width, signum, name_width, signame,
 181           description ? description : "?");
 182 }
 183
 184 /* Print a list of signal names.  If TABLE, print a table.
 185    Print the names specified by ARGV if nonzero; otherwise,
 186    print all known names.  Return a suitable exit status.  */
 187
 188 static int
 189 list_signals (bool table, char *const *argv)
 190 {
 191   int signum;
 192   int status = EXIT_SUCCESS;
 193   char signame[SIG2STR_MAX];
 194
 195   if (table)
 196     {
 197       unsigned int name_width = 0;
 198
 199       /* Compute the maximum width of a signal number.  */
 200       unsigned int num_width = 1;
 201       for (signum = 1; signum <= SIGNUM_BOUND / 10; signum *= 10)
 202         num_width++;
 203
 204       /* Compute the maximum width of a signal name.  */
 205       for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 206         if (sig2str (signum, signame) == 0)
 207           {
 208             size_t len = strlen (signame);
 209             if (name_width < len)
 210               name_width = len;
 211           }
 212
 213       if (argv)
 214         for (; *argv; argv++)
 215           {
 216             signum = operand2sig (*argv, signame);
 217             if (signum < 0)
 218               status = EXIT_FAILURE;
 219             else
 220               print_table_row (num_width, signum, name_width, signame);
 221           }
 222       else
 223         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 224           if (sig2str (signum, signame) == 0)
 225             print_table_row (num_width, signum, name_width, signame);
 226     }
 227   else
 228     {
 229       if (argv)
 230         for (; *argv; argv++)
 231           {
 232             signum = operand2sig (*argv, signame);
 233             if (signum < 0)
 234               status = EXIT_FAILURE;
 235             else
 236               {
 237                 if (ISDIGIT (**argv))
 238                   puts (signame);
 239                 else
 240                   printf ("%d\n", signum);
 241               }
 242           }
 243       else
 244         for (signum = 1; signum <= SIGNUM_BOUND; signum++)
 245           if (sig2str (signum, signame) == 0)
 246             puts (signame);
 247     }
 248
 249   return status;
 250 }
 251 \f
 252 /* Send signal SIGNUM to all the processes or process groups specified
 253    by ARGV.  Return a suitable exit status.  */
 254
 255 static int
 256 send_signals (int signum, char *const *argv)
 257 {
 258   int status = EXIT_SUCCESS;
 259   char const *arg = *argv;
 260
 261   do
 262     {
 263       char *endp;
 264       intmax_t n = (errno = 0, strtoimax (arg, &endp, 10));
 265       pid_t pid = n;
 266
 267       if (errno == ERANGE || pid != n || arg == endp || *endp)
 268         {
 269           error (0, 0, _("%s: invalid process id"), arg);
 270           status = EXIT_FAILURE;
 271         }
 272       else if (kill (pid, signum) != 0)
 273         {
 274           error (0, errno, "%s", arg);
 275           status = EXIT_FAILURE;
 276         }
 277     }
 278   while ((arg = *++argv));
 279
 280   return status;
 281 }
 282 \f
 283 int
 284 main (int argc, char **argv)
 285 {
 286   int optc;
 287   bool list = false;
 288   bool table = false;
 289   int signum = -1;
 290   char signame[SIG2STR_MAX];
 291
 292   initialize_main (&argc, &argv);
 293   program_name = argv[0];
 294   setlocale (LC_ALL, "");
 295   bindtextdomain (PACKAGE, LOCALEDIR);
 296   textdomain (PACKAGE);
 297
 298   atexit (close_stdout);
 299
 300   while ((optc = getopt_long (argc, argv, short_options, long_options, NULL))
 301          != -1)
 302     switch (optc)
 303       {
 304       case '0': case '1': case '2': case '3': case '4':
 305       case '5': case '6': case '7': case '8': case '9':
 306         if (optind != 2)
 307           {
 308             /* This option is actually a process-id.  */
 309             optind--;
 310             goto no_more_options;
 311           }
 312         /* Fall through.  */
 313       case 'A': case 'B': case 'C': case 'D': case 'E':
 314       case 'F': case 'G': case 'H': case 'I': case 'J':
 315       case 'K': case 'L': case 'M': case 'N': case 'O':
 316       case 'P': case 'Q': case 'R': case 'S': case 'T':
 317       case 'U': case 'V': case 'W': case 'X': case 'Y':
 318       case 'Z':
 319         if (! optarg)
 320           optarg = argv[optind - 1] + strlen (argv[optind - 1]);
 321         if (optarg != argv[optind - 1] + 2)
 322           {
 323             error (0, 0, _("invalid option -- %c"), optc);
 324             usage (EXIT_FAILURE);
 325           }
 326         optarg--;
 327         /* Fall through.  */
 328       case 'n': /* -n is not documented, but is for Bash compatibility.  */
 329       case 's':
 330         if (0 <= signum)
 331           {
 332             error (0, 0, _("%s: multiple signals specified"), optarg);
 333             usage (EXIT_FAILURE);
 334           }
 335         signum = operand2sig (optarg, signame);
 336         if (signum < 0)
 337           usage (EXIT_FAILURE);
 338         break;
 339
 340       case 't':
 341         table = true;
 342         /* Fall through.  */
 343       case 'l':
 344         if (list)
 345           {
 346             error (0, 0, _("multiple -l or -t options specified"));
 347             usage (EXIT_FAILURE);
 348           }
 349         list = true;
 350         break;
 351
 352       case_GETOPT_HELP_CHAR;
 353       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 354       default:
 355         usage (EXIT_FAILURE);
 356       }
 357  no_more_options:;
 358
 359   if (signum < 0)
 360     signum = SIGTERM;
 361   else if (list)
 362     {
 363       error (0, 0, _("cannot combine signal with -l or -t"));
 364       usage (EXIT_FAILURE);
 365     }
 366
 367   if ( ! list && argc <= optind)
 368     {
 369       error (0, 0, _("no process ID specified"));
 370       usage (EXIT_FAILURE);
 371     }
 372
 373   return (list
 374           ? list_signals (table, optind < argc ? argv + optind : NULL)
 375           : send_signals (signum, argv + optind));
 376 }