usr.bin/timeout/timeout.c

   1 /*-
   2  * Copyright (c) 2014 Baptiste Daroussin <bapt@FreeBSD.org>
   3  * Copyright (c) 2014 Vsevolod Stakhov <vsevolod@FreeBSD.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer
  11  *    in this position and unchanged.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include <sys/cdefs.h>
  29 __FBSDID("$FreeBSD$");
  30
  31 #include <sys/time.h>
  32 #include <sys/wait.h>
  33
  34 #include <err.h>
  35 #include <errno.h>
  36 #include <getopt.h>
  37 #include <signal.h>
  38 #include <stdbool.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <sysexits.h>
  43 #include <unistd.h>
  44
  45 #define EXIT_TIMEOUT 124
  46
  47 static sig_atomic_t sig_chld = 0;
  48 static sig_atomic_t sig_term = 0;
  49 static sig_atomic_t sig_alrm = 0;
  50 static sig_atomic_t sig_ign = 0;
  51
  52 static void
  53 usage(void)
  54 {
  55
  56         fprintf(stderr, "Usage: %s [--signal sig | -s sig] [--preserve-status]"
  57             " [--kill-after time | -k time] [--foreground] <duration> <command>"
  58             " <arg ...>\n", getprogname());
  59
  60         exit(EX_USAGE);
  61 }
  62
  63 static double
  64 parse_duration(const char *duration)
  65 {
  66         double ret;
  67         char *end;
  68
  69         ret = strtod(duration, &end);
  70         if (ret == 0 && end == duration)
  71                 errx(125, "invalid duration");
  72
  73         if (end == NULL || *end == '\0')
  74                 return (ret);
  75
  76         if (end != NULL && *(end + 1) != '\0')
  77                 errx(EX_USAGE, "invalid duration");
  78
  79         switch (*end) {
  80         case 's':
  81                 break;
  82         case 'm':
  83                 ret *= 60;
  84                 break;
  85         case 'h':
  86                 ret *= 60 * 60;
  87                 break;
  88         case 'd':
  89                 ret *= 60 * 60 * 24;
  90                 break;
  91         default:
  92                 errx(125, "invalid duration");
  93         }
  94
  95         if (ret < 0 || ret >= 100000000UL)
  96                 errx(125, "invalid duration");
  97
  98         return (ret);
  99 }
 100
 101 static int
 102 parse_signal(const char *str)
 103 {
 104         int sig, i;
 105         const char *errstr;
 106
 107         sig = strtonum(str, 0, sys_nsig, &errstr);
 108
 109         if (errstr == NULL)
 110                 return (sig);
 111         if (strncasecmp(str, "SIG", 3) == 0)
 112                 str += 3;
 113
 114         for (i = 1; i < sys_nsig; i++) {
 115                 if (strcasecmp(str, sys_signame[i]) == 0)
 116                         return (i);
 117         }
 118
 119         errx(125, "invalid signal");
 120 }
 121
 122 static void
 123 sig_handler(int signo)
 124 {
 125         if (sig_ign != 0 && signo == sig_ign) {
 126                 sig_ign = 0;
 127                 return;
 128         }
 129
 130         switch(signo) {
 131         case 0:
 132         case SIGINT:
 133         case SIGHUP:
 134         case SIGQUIT:
 135         case SIGTERM:
 136                 sig_term = signo;
 137                 break;
 138         case SIGCHLD:
 139                 sig_chld = 1;
 140                 break;
 141         case SIGALRM:
 142                 sig_alrm = 1;
 143                 break;
 144         }
 145 }
 146
 147 static void
 148 set_interval(double iv)
 149 {
 150         struct itimerval tim;
 151
 152         memset(&tim, 0, sizeof(tim));
 153         tim.it_value.tv_sec = (time_t)iv;
 154         iv -= (time_t)iv;
 155         tim.it_value.tv_usec = (suseconds_t)(iv * 1000000UL);
 156
 157         if (setitimer(ITIMER_REAL, &tim, NULL) == -1)
 158                 err(EX_OSERR, "setitimer()");
 159 }
 160
 161 int
 162 main(int argc, char **argv)
 163 {
 164         int ch;
 165         unsigned long i;
 166         int foreground, preserve;
 167         int error, pstat, status;
 168         int killsig = SIGTERM;
 169         pid_t pgid, pid, cpid;
 170         double first_kill;
 171         double second_kill;
 172         bool timedout = false;
 173         bool do_second_kill = false;
 174         struct sigaction signals;
 175         int signums[] = {
 176                 -1,
 177                 SIGTERM,
 178                 SIGINT,
 179                 SIGHUP,
 180                 SIGCHLD,
 181                 SIGALRM,
 182                 SIGQUIT,
 183         };
 184
 185         foreground = preserve = 0;
 186         second_kill = 0;
 187         cpid = -1;
 188         pgid = -1;
 189
 190         const struct option longopts[] = {
 191                 { "preserve-status", no_argument,       &preserve,    1 },
 192                 { "foreground",      no_argument,       &foreground,  1 },
 193                 { "kill-after",      required_argument, NULL,        'k'},
 194                 { "signal",          required_argument, NULL,        's'},
 195                 { "help",            no_argument,       NULL,        'h'},
 196                 { NULL,              0,                 NULL,         0 }
 197         };
 198
 199         while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) {
 200                 switch (ch) {
 201                         case 'k':
 202                                 do_second_kill = true;
 203                                 second_kill = parse_duration(optarg);
 204                                 break;
 205                         case 's':
 206                                 killsig = parse_signal(optarg);
 207                                 break;
 208                         case 0:
 209                                 break;
 210                         case 'h':
 211                         default:
 212                                 usage();
 213                                 break;
 214                 }
 215         }
 216
 217         argc -= optind;
 218         argv += optind;
 219
 220         if (argc < 2)
 221                 usage();
 222
 223         first_kill = parse_duration(argv[0]);
 224         argc--;
 225         argv++;
 226
 227         if (!foreground) {
 228                 pgid = setpgid(0,0);
 229
 230                 if (pgid == -1)
 231                         err(EX_OSERR, "setpgid()");
 232         }
 233
 234         memset(&signals, 0, sizeof(signals));
 235         sigemptyset(&signals.sa_mask);
 236
 237         if (killsig != SIGKILL && killsig != SIGSTOP)
 238                 signums[0] = killsig;
 239
 240         for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i ++)
 241                 sigaddset(&signals.sa_mask, signums[i]);
 242
 243         signals.sa_handler = sig_handler;
 244         signals.sa_flags = SA_RESTART;
 245
 246         for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i ++)
 247                 if (signums[i] != -1 && signums[i] != 0 &&
 248                     sigaction(signums[i], &signals, NULL) == -1)
 249                         err(EX_OSERR, "sigaction()");
 250
 251         signal(SIGTTIN, SIG_IGN);
 252         signal(SIGTTOU, SIG_IGN);
 253
 254         pid = fork();
 255         if (pid == -1)
 256                 err(EX_OSERR, "fork()");
 257         else if (pid == 0) {
 258                 /* child process */
 259                 signal(SIGTTIN, SIG_DFL);
 260                 signal(SIGTTOU, SIG_DFL);
 261
 262                 error = execvp(argv[0], argv);
 263                 if (error == -1) {
 264                         if (errno == ENOENT)
 265                                 err(127, "exec(%s)", argv[0]);
 266                         else
 267                                 err(126, "exec(%s)", argv[0]);
 268                 }
 269         }
 270
 271         if (sigprocmask(SIG_BLOCK, &signals.sa_mask, NULL) == -1)
 272                 err(EX_OSERR, "sigprocmask()");
 273
 274         /* parent continues here */
 275         set_interval(first_kill);
 276
 277         for (;;) {
 278                 sigemptyset(&signals.sa_mask);
 279                 sigsuspend(&signals.sa_mask);
 280
 281                 if (sig_chld) {
 282                         sig_chld = 0;
 283                         while (((cpid = wait(&status)) < 0) && errno == EINTR)
 284                                 continue;
 285
 286                         if (cpid == pid) {
 287                                 pstat = status;
 288                                 break;
 289                         }
 290                 } else if (sig_alrm) {
 291                         sig_alrm = 0;
 292
 293                         timedout = true;
 294                         if (!foreground)
 295                                 killpg(pgid, killsig);
 296                         else
 297                                 kill(pid, killsig);
 298
 299                         if (do_second_kill) {
 300                                 set_interval(second_kill);
 301                                 second_kill = 0;
 302                                 sig_ign = killsig;
 303                                 killsig = SIGKILL;
 304                         } else
 305                                 break;
 306
 307                 } else if (sig_term) {
 308                         if (!foreground)
 309                                 killpg(pgid, killsig);
 310                         else
 311                                 kill(pid, sig_term);
 312
 313                         if (do_second_kill) {
 314                                 set_interval(second_kill);
 315                                 second_kill = 0;
 316                                 sig_ign = killsig;
 317                                 killsig = SIGKILL;
 318                         } else
 319                                 break;
 320                 }
 321         }
 322
 323         while (cpid != pid  && wait(&pstat) == -1) {
 324                 if (errno != EINTR)
 325                         err(EX_OSERR, "waitpid()");
 326         }
 327
 328         if (WEXITSTATUS(pstat))
 329                 pstat = WEXITSTATUS(pstat);
 330         else if(WIFSIGNALED(pstat))
 331                 pstat = 128 + WTERMSIG(pstat);
 332
 333         if (timedout && !preserve)
 334                 pstat = EXIT_TIMEOUT;
 335
 336         return (pstat);
 337 }