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/procctl.h>
  32 #include <sys/time.h>
  33 #include <sys/wait.h>
  34
  35 #include <err.h>
  36 #include <errno.h>
  37 #include <getopt.h>
  38 #include <signal.h>
  39 #include <stdbool.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.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(EXIT_FAILURE);
  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(125, "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, 1, sys_nsig - 1, &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(EXIT_FAILURE, "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 pid, cpid;
 170         double first_kill;
 171         double second_kill;
 172         bool timedout = false;
 173         bool do_second_kill = false;
 174         bool child_done = false;
 175         struct sigaction signals;
 176         struct procctl_reaper_status info;
 177         struct procctl_reaper_kill killemall;
 178         int signums[] = {
 179                 -1,
 180                 SIGTERM,
 181                 SIGINT,
 182                 SIGHUP,
 183                 SIGCHLD,
 184                 SIGALRM,
 185                 SIGQUIT,
 186         };
 187
 188         foreground = preserve = 0;
 189         second_kill = 0;
 190
 191         const struct option longopts[] = {
 192                 { "preserve-status", no_argument,       &preserve,    1 },
 193                 { "foreground",      no_argument,       &foreground,  1 },
 194                 { "kill-after",      required_argument, NULL,        'k'},
 195                 { "signal",          required_argument, NULL,        's'},
 196                 { "help",            no_argument,       NULL,        'h'},
 197                 { NULL,              0,                 NULL,         0 }
 198         };
 199
 200         while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) {
 201                 switch (ch) {
 202                         case 'k':
 203                                 do_second_kill = true;
 204                                 second_kill = parse_duration(optarg);
 205                                 break;
 206                         case 's':
 207                                 killsig = parse_signal(optarg);
 208                                 break;
 209                         case 0:
 210                                 break;
 211                         case 'h':
 212                         default:
 213                                 usage();
 214                                 break;
 215                 }
 216         }
 217
 218         argc -= optind;
 219         argv += optind;
 220
 221         if (argc < 2)
 222                 usage();
 223
 224         first_kill = parse_duration(argv[0]);
 225         argc--;
 226         argv++;
 227
 228         if (!foreground) {
 229                 /* Acquire a reaper */
 230                 if (procctl(P_PID, getpid(), PROC_REAP_ACQUIRE, NULL) == -1)
 231                         err(EXIT_FAILURE, "Fail to acquire the reaper");
 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(EXIT_FAILURE, "sigaction()");
 250
 251         signal(SIGTTIN, SIG_IGN);
 252         signal(SIGTTOU, SIG_IGN);
 253
 254         pid = fork();
 255         if (pid == -1)
 256                 err(EXIT_FAILURE, "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(EXIT_FAILURE, "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
 284                         while ((cpid = waitpid(-1, &status, WNOHANG)) != 0) {
 285                                 if (cpid < 0) {
 286                                         if (errno == EINTR)
 287                                                 continue;
 288                                         else
 289                                                 break;
 290                                 } else if (cpid == pid) {
 291                                         pstat = status;
 292                                         child_done = true;
 293                                 }
 294                         }
 295                         if (child_done) {
 296                                 if (foreground) {
 297                                         break;
 298                                 } else {
 299                                         procctl(P_PID, getpid(),
 300                                             PROC_REAP_STATUS, &info);
 301                                         if (info.rs_children == 0)
 302                                                 break;
 303                                 }
 304                         }
 305                 } else if (sig_alrm) {
 306                         sig_alrm = 0;
 307
 308                         timedout = true;
 309                         if (!foreground) {
 310                                 killemall.rk_sig = killsig;
 311                                 killemall.rk_flags = 0;
 312                                 procctl(P_PID, getpid(), PROC_REAP_KILL,
 313                                     &killemall);
 314                         } else
 315                                 kill(pid, killsig);
 316
 317                         if (do_second_kill) {
 318                                 set_interval(second_kill);
 319                                 second_kill = 0;
 320                                 sig_ign = killsig;
 321                                 killsig = SIGKILL;
 322                         } else
 323                                 break;
 324
 325                 } else if (sig_term) {
 326                         if (!foreground) {
 327                                 killemall.rk_sig = sig_term;
 328                                 killemall.rk_flags = 0;
 329                                 procctl(P_PID, getpid(), PROC_REAP_KILL,
 330                                     &killemall);
 331                         } else
 332                                 kill(pid, sig_term);
 333
 334                         if (do_second_kill) {
 335                                 set_interval(second_kill);
 336                                 second_kill = 0;
 337                                 sig_ign = killsig;
 338                                 killsig = SIGKILL;
 339                         } else
 340                                 break;
 341                 }
 342         }
 343
 344         while (!child_done && wait(&pstat) == -1) {
 345                 if (errno != EINTR)
 346                         err(EXIT_FAILURE, "waitpid()");
 347         }
 348
 349         if (!foreground)
 350                 procctl(P_PID, getpid(), PROC_REAP_RELEASE, NULL);
 351
 352         if (WEXITSTATUS(pstat))
 353                 pstat = WEXITSTATUS(pstat);
 354         else if (WIFSIGNALED(pstat))
 355                 pstat = 128 + WTERMSIG(pstat);
 356
 357         if (timedout && !preserve)
 358                 pstat = EXIT_TIMEOUT;
 359
 360         return (pstat);
 361 }