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 <sysexits.h>
  44 #include <unistd.h>
  45
  46 #define EXIT_TIMEOUT 124
  47
  48 static sig_atomic_t sig_chld = 0;
  49 static sig_atomic_t sig_term = 0;
  50 static sig_atomic_t sig_alrm = 0;
  51 static sig_atomic_t sig_ign = 0;
  52
  53 static void
  54 usage(void)
  55 {
  56
  57         fprintf(stderr, "Usage: %s [--signal sig | -s sig] [--preserve-status]"
  58             " [--kill-after time | -k time] [--foreground] <duration> <command>"
  59             " <arg ...>\n", getprogname());
  60
  61         exit(EX_USAGE);
  62 }
  63
  64 static double
  65 parse_duration(const char *duration)
  66 {
  67         double ret;
  68         char *end;
  69
  70         ret = strtod(duration, &end);
  71         if (ret == 0 && end == duration)
  72                 errx(125, "invalid duration");
  73
  74         if (end == NULL || *end == '\0')
  75                 return (ret);
  76
  77         if (end != NULL && *(end + 1) != '\0')
  78                 errx(EX_USAGE, "invalid duration");
  79
  80         switch (*end) {
  81         case 's':
  82                 break;
  83         case 'm':
  84                 ret *= 60;
  85                 break;
  86         case 'h':
  87                 ret *= 60 * 60;
  88                 break;
  89         case 'd':
  90                 ret *= 60 * 60 * 24;
  91                 break;
  92         default:
  93                 errx(125, "invalid duration");
  94         }
  95
  96         if (ret < 0 || ret >= 100000000UL)
  97                 errx(125, "invalid duration");
  98
  99         return (ret);
 100 }
 101
 102 static int
 103 parse_signal(const char *str)
 104 {
 105         int sig, i;
 106         const char *errstr;
 107
 108         sig = strtonum(str, 1, sys_nsig - 1, &errstr);
 109
 110         if (errstr == NULL)
 111                 return (sig);
 112         if (strncasecmp(str, "SIG", 3) == 0)
 113                 str += 3;
 114
 115         for (i = 1; i < sys_nsig; i++) {
 116                 if (strcasecmp(str, sys_signame[i]) == 0)
 117                         return (i);
 118         }
 119
 120         errx(125, "invalid signal");
 121 }
 122
 123 static void
 124 sig_handler(int signo)
 125 {
 126         if (sig_ign != 0 && signo == sig_ign) {
 127                 sig_ign = 0;
 128                 return;
 129         }
 130
 131         switch(signo) {
 132         case 0:
 133         case SIGINT:
 134         case SIGHUP:
 135         case SIGQUIT:
 136         case SIGTERM:
 137                 sig_term = signo;
 138                 break;
 139         case SIGCHLD:
 140                 sig_chld = 1;
 141                 break;
 142         case SIGALRM:
 143                 sig_alrm = 1;
 144                 break;
 145         }
 146 }
 147
 148 static void
 149 set_interval(double iv)
 150 {
 151         struct itimerval tim;
 152
 153         memset(&tim, 0, sizeof(tim));
 154         tim.it_value.tv_sec = (time_t)iv;
 155         iv -= (time_t)iv;
 156         tim.it_value.tv_usec = (suseconds_t)(iv * 1000000UL);
 157
 158         if (setitimer(ITIMER_REAL, &tim, NULL) == -1)
 159                 err(EX_OSERR, "setitimer()");
 160 }
 161
 162 int
 163 main(int argc, char **argv)
 164 {
 165         int ch;
 166         unsigned long i;
 167         int foreground, preserve;
 168         int error, pstat, status;
 169         int killsig = SIGTERM;
 170         pid_t pid, cpid;
 171         double first_kill;
 172         double second_kill;
 173         bool timedout = false;
 174         bool do_second_kill = false;
 175         bool child_done = false;
 176         struct sigaction signals;
 177         struct procctl_reaper_status info;
 178         struct procctl_reaper_kill killemall;
 179         int signums[] = {
 180                 -1,
 181                 SIGTERM,
 182                 SIGINT,
 183                 SIGHUP,
 184                 SIGCHLD,
 185                 SIGALRM,
 186                 SIGQUIT,
 187         };
 188
 189         foreground = preserve = 0;
 190         second_kill = 0;
 191
 192         const struct option longopts[] = {
 193                 { "preserve-status", no_argument,       &preserve,    1 },
 194                 { "foreground",      no_argument,       &foreground,  1 },
 195                 { "kill-after",      required_argument, NULL,        'k'},
 196                 { "signal",          required_argument, NULL,        's'},
 197                 { "help",            no_argument,       NULL,        'h'},
 198                 { NULL,              0,                 NULL,         0 }
 199         };
 200
 201         while ((ch = getopt_long(argc, argv, "+k:s:h", longopts, NULL)) != -1) {
 202                 switch (ch) {
 203                         case 'k':
 204                                 do_second_kill = true;
 205                                 second_kill = parse_duration(optarg);
 206                                 break;
 207                         case 's':
 208                                 killsig = parse_signal(optarg);
 209                                 break;
 210                         case 0:
 211                                 break;
 212                         case 'h':
 213                         default:
 214                                 usage();
 215                                 break;
 216                 }
 217         }
 218
 219         argc -= optind;
 220         argv += optind;
 221
 222         if (argc < 2)
 223                 usage();
 224
 225         first_kill = parse_duration(argv[0]);
 226         argc--;
 227         argv++;
 228
 229         if (!foreground) {
 230                 /* Acquire a reaper */
 231                 if (procctl(P_PID, getpid(), PROC_REAP_ACQUIRE, NULL) == -1)
 232                         err(EX_OSERR, "Fail to acquire the reaper");
 233         }
 234
 235         memset(&signals, 0, sizeof(signals));
 236         sigemptyset(&signals.sa_mask);
 237
 238         if (killsig != SIGKILL && killsig != SIGSTOP)
 239                 signums[0] = killsig;
 240
 241         for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i ++)
 242                 sigaddset(&signals.sa_mask, signums[i]);
 243
 244         signals.sa_handler = sig_handler;
 245         signals.sa_flags = SA_RESTART;
 246
 247         for (i = 0; i < sizeof(signums) / sizeof(signums[0]); i ++)
 248                 if (signums[i] != -1 && signums[i] != 0 &&
 249                     sigaction(signums[i], &signals, NULL) == -1)
 250                         err(EX_OSERR, "sigaction()");
 251
 252         signal(SIGTTIN, SIG_IGN);
 253         signal(SIGTTOU, SIG_IGN);
 254
 255         pid = fork();
 256         if (pid == -1)
 257                 err(EX_OSERR, "fork()");
 258         else if (pid == 0) {
 259                 /* child process */
 260                 signal(SIGTTIN, SIG_DFL);
 261                 signal(SIGTTOU, SIG_DFL);
 262
 263                 error = execvp(argv[0], argv);
 264                 if (error == -1) {
 265                         if (errno == ENOENT)
 266                                 err(127, "exec(%s)", argv[0]);
 267                         else
 268                                 err(126, "exec(%s)", argv[0]);
 269                 }
 270         }
 271
 272         if (sigprocmask(SIG_BLOCK, &signals.sa_mask, NULL) == -1)
 273                 err(EX_OSERR, "sigprocmask()");
 274
 275         /* parent continues here */
 276         set_interval(first_kill);
 277
 278         for (;;) {
 279                 sigemptyset(&signals.sa_mask);
 280                 sigsuspend(&signals.sa_mask);
 281
 282                 if (sig_chld) {
 283                         sig_chld = 0;
 284
 285                         while ((cpid = waitpid(-1, &status, WNOHANG)) != 0) {
 286                                 if (cpid < 0) {
 287                                         if (errno == EINTR)
 288                                                 continue;
 289                                         else
 290                                                 break;
 291                                 } else if (cpid == pid) {
 292                                         pstat = status;
 293                                         child_done = true;
 294                                 }
 295                         }
 296                         if (child_done) {
 297                                 if (foreground) {
 298                                         break;
 299                                 } else {
 300                                         procctl(P_PID, getpid(),
 301                                             PROC_REAP_STATUS, &info);
 302                                         if (info.rs_children == 0)
 303                                                 break;
 304                                 }
 305                         }
 306                 } else if (sig_alrm) {
 307                         sig_alrm = 0;
 308
 309                         timedout = true;
 310                         if (!foreground) {
 311                                 killemall.rk_sig = killsig;
 312                                 killemall.rk_flags = 0;
 313                                 procctl(P_PID, getpid(), PROC_REAP_KILL,
 314                                     &killemall);
 315                         } else
 316                                 kill(pid, killsig);
 317
 318                         if (do_second_kill) {
 319                                 set_interval(second_kill);
 320                                 second_kill = 0;
 321                                 sig_ign = killsig;
 322                                 killsig = SIGKILL;
 323                         } else
 324                                 break;
 325
 326                 } else if (sig_term) {
 327                         if (!foreground) {
 328                                 killemall.rk_sig = sig_term;
 329                                 killemall.rk_flags = 0;
 330                                 procctl(P_PID, getpid(), PROC_REAP_KILL,
 331                                     &killemall);
 332                         } else
 333                                 kill(pid, sig_term);
 334
 335                         if (do_second_kill) {
 336                                 set_interval(second_kill);
 337                                 second_kill = 0;
 338                                 sig_ign = killsig;
 339                                 killsig = SIGKILL;
 340                         } else
 341                                 break;
 342                 }
 343         }
 344
 345         while (!child_done && wait(&pstat) == -1) {
 346                 if (errno != EINTR)
 347                         err(EX_OSERR, "waitpid()");
 348         }
 349
 350         if (!foreground)
 351                 procctl(P_PID, getpid(), PROC_REAP_RELEASE, NULL);
 352
 353         if (WEXITSTATUS(pstat))
 354                 pstat = WEXITSTATUS(pstat);
 355         else if(WIFSIGNALED(pstat))
 356                 pstat = 128 + WTERMSIG(pstat);
 357
 358         if (timedout && !preserve)
 359                 pstat = EXIT_TIMEOUT;
 360
 361         return (pstat);
 362 }