miscutils/time.c

   1 /* vi: set sw=4 ts=4: */
   2 /* 'time' utility to display resource usage of processes.
   3    Copyright (C) 1990, 91, 92, 93, 96 Free Software Foundation, Inc.
   4
   5    Licensed under GPL version 2, see file LICENSE in this tarball for details.
   6 */
   7 /* Originally written by David Keppel <pardo@cs.washington.edu>.
   8    Heavily modified by David MacKenzie <djm@gnu.ai.mit.edu>.
   9    Heavily modified for busybox by Erik Andersen <andersen@codepoet.org>
  10 */
  11
  12 #include "libbb.h"
  13
  14 /* Information on the resources used by a child process.  */
  15 typedef struct {
  16         int waitstatus;
  17         struct rusage ru;
  18         unsigned elapsed_ms;    /* Wallclock time of process.  */
  19 } resource_t;
  20
  21 /* msec = milliseconds = 1/1,000 (1*10e-3) second.
  22    usec = microseconds = 1/1,000,000 (1*10e-6) second.  */
  23
  24 #define UL unsigned long
  25
  26 static const char default_format[] ALIGN1 = "real\t%E\nuser\t%u\nsys\t%T";
  27
  28 /* The output format for the -p option .*/
  29 static const char posix_format[] ALIGN1 = "real %e\nuser %U\nsys %S";
  30
  31 /* Format string for printing all statistics verbosely.
  32    Keep this output to 24 lines so users on terminals can see it all.*/
  33 static const char long_format[] ALIGN1 =
  34         "\tCommand being timed: \"%C\"\n"
  35         "\tUser time (seconds): %U\n"
  36         "\tSystem time (seconds): %S\n"
  37         "\tPercent of CPU this job got: %P\n"
  38         "\tElapsed (wall clock) time (h:mm:ss or m:ss): %E\n"
  39         "\tAverage shared text size (kbytes): %X\n"
  40         "\tAverage unshared data size (kbytes): %D\n"
  41         "\tAverage stack size (kbytes): %p\n"
  42         "\tAverage total size (kbytes): %K\n"
  43         "\tMaximum resident set size (kbytes): %M\n"
  44         "\tAverage resident set size (kbytes): %t\n"
  45         "\tMajor (requiring I/O) page faults: %F\n"
  46         "\tMinor (reclaiming a frame) page faults: %R\n"
  47         "\tVoluntary context switches: %w\n"
  48         "\tInvoluntary context switches: %c\n"
  49         "\tSwaps: %W\n"
  50         "\tFile system inputs: %I\n"
  51         "\tFile system outputs: %O\n"
  52         "\tSocket messages sent: %s\n"
  53         "\tSocket messages received: %r\n"
  54         "\tSignals delivered: %k\n"
  55         "\tPage size (bytes): %Z\n"
  56         "\tExit status: %x";
  57
  58 /* Wait for and fill in data on child process PID.
  59    Return 0 on error, 1 if ok.  */
  60 /* pid_t is short on BSDI, so don't try to promote it.  */
  61 static void resuse_end(pid_t pid, resource_t *resp)
  62 {
  63         pid_t caught;
  64
  65         /* Ignore signals, but don't ignore the children.  When wait3
  66            returns the child process, set the time the command finished. */
  67         while ((caught = wait3(&resp->waitstatus, 0, &resp->ru)) != pid) {
  68                 if (caught == -1 && errno != EINTR) {
  69                         bb_perror_msg("wait");
  70                         return;
  71                 }
  72         }
  73         resp->elapsed_ms = (monotonic_us() / 1000) - resp->elapsed_ms;
  74 }
  75
  76 static void printargv(char *const *argv)
  77 {
  78         const char *fmt = " %s" + 1;
  79         do {
  80                 printf(fmt, *argv);
  81                 fmt = " %s";
  82         } while (*++argv);
  83 }
  84
  85 /* Return the number of kilobytes corresponding to a number of pages PAGES.
  86    (Actually, we use it to convert pages*ticks into kilobytes*ticks.)
  87
  88    Try to do arithmetic so that the risk of overflow errors is minimized.
  89    This is funky since the pagesize could be less than 1K.
  90    Note: Some machines express getrusage statistics in terms of K,
  91    others in terms of pages.  */
  92 static unsigned long ptok(unsigned pagesize, unsigned long pages)
  93 {
  94         unsigned long tmp;
  95
  96         /* Conversion.  */
  97         if (pages > (LONG_MAX / pagesize)) { /* Could overflow.  */
  98                 tmp = pages / 1024;     /* Smaller first, */
  99                 return tmp * pagesize;  /* then larger.  */
 100         }
 101         /* Could underflow.  */
 102         tmp = pages * pagesize; /* Larger first, */
 103         return tmp / 1024;      /* then smaller.  */
 104 }
 105
 106 /* summarize: Report on the system use of a command.
 107
 108    Print the FMT argument except that `%' sequences
 109    have special meaning, and `\n' and `\t' are translated into
 110    newline and tab, respectively, and `\\' is translated into `\'.
 111
 112    The character following a `%' can be:
 113    (* means the tcsh time builtin also recognizes it)
 114    % == a literal `%'
 115    C == command name and arguments
 116 *  D == average unshared data size in K (ru_idrss+ru_isrss)
 117 *  E == elapsed real (wall clock) time in [hour:]min:sec
 118 *  F == major page faults (required physical I/O) (ru_majflt)
 119 *  I == file system inputs (ru_inblock)
 120 *  K == average total mem usage (ru_idrss+ru_isrss+ru_ixrss)
 121 *  M == maximum resident set size in K (ru_maxrss)
 122 *  O == file system outputs (ru_oublock)
 123 *  P == percent of CPU this job got (total cpu time / elapsed time)
 124 *  R == minor page faults (reclaims; no physical I/O involved) (ru_minflt)
 125 *  S == system (kernel) time (seconds) (ru_stime)
 126 *  T == system time in [hour:]min:sec
 127 *  U == user time (seconds) (ru_utime)
 128 *  u == user time in [hour:]min:sec
 129 *  W == times swapped out (ru_nswap)
 130 *  X == average amount of shared text in K (ru_ixrss)
 131    Z == page size
 132 *  c == involuntary context switches (ru_nivcsw)
 133    e == elapsed real time in seconds
 134 *  k == signals delivered (ru_nsignals)
 135    p == average unshared stack size in K (ru_isrss)
 136 *  r == socket messages received (ru_msgrcv)
 137 *  s == socket messages sent (ru_msgsnd)
 138    t == average resident set size in K (ru_idrss)
 139 *  w == voluntary context switches (ru_nvcsw)
 140    x == exit status of command
 141
 142    Various memory usages are found by converting from page-seconds
 143    to kbytes by multiplying by the page size, dividing by 1024,
 144    and dividing by elapsed real time.
 145
 146    FMT is the format string, interpreted as described above.
 147    COMMAND is the command and args that are being summarized.
 148    RESP is resource information on the command.  */
 149
 150 #ifndef TICKS_PER_SEC
 151 #define TICKS_PER_SEC 100
 152 #endif
 153
 154 static void summarize(const char *fmt, char **command, resource_t *resp)
 155 {
 156         unsigned vv_ms;     /* Elapsed virtual (CPU) milliseconds */
 157         unsigned cpu_ticks; /* Same, in "CPU ticks" */
 158         unsigned pagesize = getpagesize();
 159
 160         /* Impossible: we do not use WUNTRACED flag in wait()...
 161         if (WIFSTOPPED(resp->waitstatus))
 162                 printf("Command stopped by signal %u\n",
 163                                 WSTOPSIG(resp->waitstatus));
 164         else */
 165         if (WIFSIGNALED(resp->waitstatus))
 166                 printf("Command terminated by signal %u\n",
 167                                 WTERMSIG(resp->waitstatus));
 168         else if (WIFEXITED(resp->waitstatus) && WEXITSTATUS(resp->waitstatus))
 169                 printf("Command exited with non-zero status %u\n",
 170                                 WEXITSTATUS(resp->waitstatus));
 171
 172         vv_ms = (resp->ru.ru_utime.tv_sec + resp->ru.ru_stime.tv_sec) * 1000
 173               + (resp->ru.ru_utime.tv_usec + resp->ru.ru_stime.tv_usec) / 1000;
 174
 175 #if (1000 / TICKS_PER_SEC) * TICKS_PER_SEC == 1000
 176         /* 1000 is exactly divisible by TICKS_PER_SEC (typical) */
 177         cpu_ticks = vv_ms / (1000 / TICKS_PER_SEC);
 178 #else
 179         cpu_ticks = vv_ms * (unsigned long long)TICKS_PER_SEC / 1000;
 180 #endif
 181         if (!cpu_ticks) cpu_ticks = 1; /* we divide by it, must be nonzero */
 182
 183         while (*fmt) {
 184                 /* Handle leading literal part */
 185                 int n = strcspn(fmt, "%\\");
 186                 if (n) {
 187                         printf("%.*s", n, fmt);
 188                         fmt += n;
 189                         continue;
 190                 }
 191
 192                 switch (*fmt) {
 193 #ifdef NOT_NEEDED
 194                 /* Handle literal char */
 195                 /* Usually we optimize for size, but there is a limit
 196                  * for everything. With this we do a lot of 1-byte writes */
 197                 default:
 198                         bb_putchar(*fmt);
 199                         break;
 200 #endif
 201
 202                 case '%':
 203                         switch (*++fmt) {
 204 #ifdef NOT_NEEDED_YET
 205                 /* Our format strings do not have these */
 206                 /* and we do not take format str from user */
 207                         default:
 208                                 bb_putchar('%');
 209                                 /*FALLTHROUGH*/
 210                         case '%':
 211                                 if (!*fmt) goto ret;
 212                                 bb_putchar(*fmt);
 213                                 break;
 214 #endif
 215                         case 'C':       /* The command that got timed.  */
 216                                 printargv(command);
 217                                 break;
 218                         case 'D':       /* Average unshared data size.  */
 219                                 printf("%lu",
 220                                         (ptok(pagesize, (UL) resp->ru.ru_idrss) +
 221                                          ptok(pagesize, (UL) resp->ru.ru_isrss)) / cpu_ticks);
 222                                 break;
 223                         case 'E': {     /* Elapsed real (wall clock) time.  */
 224                                 unsigned seconds = resp->elapsed_ms / 1000;
 225                                 if (seconds >= 3600)    /* One hour -> h:m:s.  */
 226                                         printf("%uh %um %02us",
 227                                                         seconds / 3600,
 228                                                         (seconds % 3600) / 60,
 229                                                         seconds % 60);
 230                                 else
 231                                         printf("%um %u.%02us",  /* -> m:s.  */
 232                                                         seconds / 60,
 233                                                         seconds % 60,
 234                                                         (unsigned)(resp->elapsed_ms / 10) % 100);
 235                                 break;
 236                         }
 237                         case 'F':       /* Major page faults.  */
 238                                 printf("%lu", resp->ru.ru_majflt);
 239                                 break;
 240                         case 'I':       /* Inputs.  */
 241                                 printf("%lu", resp->ru.ru_inblock);
 242                                 break;
 243                         case 'K':       /* Average mem usage == data+stack+text.  */
 244                                 printf("%lu",
 245                                         (ptok(pagesize, (UL) resp->ru.ru_idrss) +
 246                                          ptok(pagesize, (UL) resp->ru.ru_isrss) +
 247                                          ptok(pagesize, (UL) resp->ru.ru_ixrss)) / cpu_ticks);
 248                                 break;
 249                         case 'M':       /* Maximum resident set size.  */
 250                                 printf("%lu", ptok(pagesize, (UL) resp->ru.ru_maxrss));
 251                                 break;
 252                         case 'O':       /* Outputs.  */
 253                                 printf("%lu", resp->ru.ru_oublock);
 254                                 break;
 255                         case 'P':       /* Percent of CPU this job got.  */
 256                                 /* % cpu is (total cpu time)/(elapsed time).  */
 257                                 if (resp->elapsed_ms > 0)
 258                                         printf("%u%%", (unsigned)(vv_ms * 100 / resp->elapsed_ms));
 259                                 else
 260                                         printf("?%%");
 261                                 break;
 262                         case 'R':       /* Minor page faults (reclaims).  */
 263                                 printf("%lu", resp->ru.ru_minflt);
 264                                 break;
 265                         case 'S':       /* System time.  */
 266                                 printf("%u.%02u",
 267                                                 (unsigned)resp->ru.ru_stime.tv_sec,
 268                                                 (unsigned)(resp->ru.ru_stime.tv_usec / 10000));
 269                                 break;
 270                         case 'T':       /* System time.  */
 271                                 if (resp->ru.ru_stime.tv_sec >= 3600) /* One hour -> h:m:s.  */
 272                                         printf("%uh %um %02us",
 273                                                         (unsigned)(resp->ru.ru_stime.tv_sec / 3600),
 274                                                         (unsigned)(resp->ru.ru_stime.tv_sec % 3600) / 60,
 275                                                         (unsigned)(resp->ru.ru_stime.tv_sec % 60));
 276                                 else
 277                                         printf("%um %u.%02us",  /* -> m:s.  */
 278                                                         (unsigned)(resp->ru.ru_stime.tv_sec / 60),
 279                                                         (unsigned)(resp->ru.ru_stime.tv_sec % 60),
 280                                                         (unsigned)(resp->ru.ru_stime.tv_usec / 10000));
 281                                 break;
 282                         case 'U':       /* User time.  */
 283                                 printf("%u.%02u",
 284                                                 (unsigned)resp->ru.ru_utime.tv_sec,
 285                                                 (unsigned)(resp->ru.ru_utime.tv_usec / 10000));
 286                                 break;
 287                         case 'u':       /* User time.  */
 288                                 if (resp->ru.ru_utime.tv_sec >= 3600) /* One hour -> h:m:s.  */
 289                                         printf("%uh %um %02us",
 290                                                         (unsigned)(resp->ru.ru_utime.tv_sec / 3600),
 291                                                         (unsigned)(resp->ru.ru_utime.tv_sec % 3600) / 60,
 292                                                         (unsigned)(resp->ru.ru_utime.tv_sec % 60));
 293                                 else
 294                                         printf("%um %u.%02us",  /* -> m:s.  */
 295                                                         (unsigned)(resp->ru.ru_utime.tv_sec / 60),
 296                                                         (unsigned)(resp->ru.ru_utime.tv_sec % 60),
 297                                                         (unsigned)(resp->ru.ru_utime.tv_usec / 10000));
 298                                 break;
 299                         case 'W':       /* Times swapped out.  */
 300                                 printf("%lu", resp->ru.ru_nswap);
 301                                 break;
 302                         case 'X':       /* Average shared text size.  */
 303                                 printf("%lu", ptok(pagesize, (UL) resp->ru.ru_ixrss) / cpu_ticks);
 304                                 break;
 305                         case 'Z':       /* Page size.  */
 306                                 printf("%u", getpagesize());
 307                                 break;
 308                         case 'c':       /* Involuntary context switches.  */
 309                                 printf("%lu", resp->ru.ru_nivcsw);
 310                                 break;
 311                         case 'e':       /* Elapsed real time in seconds.  */
 312                                 printf("%u.%02u",
 313                                                 (unsigned)resp->elapsed_ms / 1000,
 314                                                 (unsigned)(resp->elapsed_ms / 10) % 100);
 315                                 break;
 316                         case 'k':       /* Signals delivered.  */
 317                                 printf("%lu", resp->ru.ru_nsignals);
 318                                 break;
 319                         case 'p':       /* Average stack segment.  */
 320                                 printf("%lu", ptok(pagesize, (UL) resp->ru.ru_isrss) / cpu_ticks);
 321                                 break;
 322                         case 'r':       /* Incoming socket messages received.  */
 323                                 printf("%lu", resp->ru.ru_msgrcv);
 324                                 break;
 325                         case 's':       /* Outgoing socket messages sent.  */
 326                                 printf("%lu", resp->ru.ru_msgsnd);
 327                                 break;
 328                         case 't':       /* Average resident set size.  */
 329                                 printf("%lu", ptok(pagesize, (UL) resp->ru.ru_idrss) / cpu_ticks);
 330                                 break;
 331                         case 'w':       /* Voluntary context switches.  */
 332                                 printf("%lu", resp->ru.ru_nvcsw);
 333                                 break;
 334                         case 'x':       /* Exit status.  */
 335                                 printf("%u", WEXITSTATUS(resp->waitstatus));
 336                                 break;
 337                         }
 338                         break;
 339
 340 #ifdef NOT_NEEDED_YET
 341                 case '\\':              /* Format escape.  */
 342                         switch (*++fmt) {
 343                         default:
 344                                 bb_putchar('\\');
 345                                 /*FALLTHROUGH*/
 346                         case '\\':
 347                                 if (!*fmt) goto ret;
 348                                 bb_putchar(*fmt);
 349                                 break;
 350                         case 't':
 351                                 bb_putchar('\t');
 352                                 break;
 353                         case 'n':
 354                                 bb_putchar('\n');
 355                                 break;
 356                         }
 357                         break;
 358 #endif
 359                 }
 360                 ++fmt;
 361         }
 362  /* ret: */
 363         bb_putchar('\n');
 364 }
 365
 366 /* Run command CMD and return statistics on it.
 367    Put the statistics in *RESP.  */
 368 static void run_command(char *const *cmd, resource_t *resp)
 369 {
 370         pid_t pid;                      /* Pid of child.  */
 371         void (*interrupt_signal)(int);
 372         void (*quit_signal)(int);
 373
 374         resp->elapsed_ms = monotonic_us() / 1000;
 375         pid = vfork();          /* Run CMD as child process.  */
 376         if (pid < 0)
 377                 bb_perror_msg_and_die("fork");
 378         if (pid == 0) { /* If child.  */
 379                 /* Don't cast execvp arguments; that causes errors on some systems,
 380                    versus merely warnings if the cast is left off.  */
 381                 BB_EXECVP(cmd[0], cmd);
 382                 xfunc_error_retval = (errno == ENOENT ? 127 : 126);
 383                 bb_error_msg_and_die("cannot run %s", cmd[0]);
 384         }
 385
 386         /* Have signals kill the child but not self (if possible).  */
 387 //TODO: just block all sigs? and reenable them in the very end in main?
 388         interrupt_signal = signal(SIGINT, SIG_IGN);
 389         quit_signal = signal(SIGQUIT, SIG_IGN);
 390
 391         resuse_end(pid, resp);
 392
 393         /* Re-enable signals.  */
 394         signal(SIGINT, interrupt_signal);
 395         signal(SIGQUIT, quit_signal);
 396 }
 397
 398 int time_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 399 int time_main(int argc UNUSED_PARAM, char **argv)
 400 {
 401         resource_t res;
 402         const char *output_format = default_format;
 403         int opt;
 404
 405         opt_complementary = "-1"; /* at least one arg */
 406         /* "+": stop on first non-option */
 407         opt = getopt32(argv, "+vp");
 408         argv += optind;
 409         if (opt & 1)
 410                 output_format = long_format;
 411         if (opt & 2)
 412                 output_format = posix_format;
 413
 414         run_command(argv, &res);
 415
 416         /* Cheat. printf's are shorter :) */
 417         /* (but see bb_putchar() body for additional wrinkle!) */
 418         xdup2(2, 1); /* just in case libc does something silly :( */
 419         stdout = stderr;
 420         summarize(output_format, argv, &res);
 421
 422         if (WIFSTOPPED(res.waitstatus))
 423                 return WSTOPSIG(res.waitstatus);
 424         if (WIFSIGNALED(res.waitstatus))
 425                 return WTERMSIG(res.waitstatus);
 426         if (WIFEXITED(res.waitstatus))
 427                 return WEXITSTATUS(res.waitstatus);
 428         fflush_stdout_and_exit(EXIT_SUCCESS);
 429 }