src/pinky.c

   1 /* GNU's pinky.
   2    Copyright (C) 1992-2024 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 3 of the License, or
   7    (at your option) 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, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Created by hacking who.c by Kaveh Ghazi ghazi@caip.rutgers.edu */
  18
  19 #include <config.h>
  20 #include <ctype.h>
  21 #include <getopt.h>
  22 #include <pwd.h>
  23 #include <stdio.h>
  24
  25 #include <sys/types.h>
  26 #include "system.h"
  27
  28 #include "canon-host.h"
  29 #include "hard-locale.h"
  30 #include "readutmp.h"
  31
  32 /* The official name of this program (e.g., no 'g' prefix).  */
  33 #define PROGRAM_NAME "pinky"
  34
  35 #define AUTHORS \
  36   proper_name ("Joseph Arceneaux"), \
  37   proper_name ("David MacKenzie"), \
  38   proper_name ("Kaveh Ghazi")
  39
  40 /* If true, display the hours:minutes since each user has touched
  41    the keyboard, or blank if within the last minute, or days followed
  42    by a 'd' if not within the last day. */
  43 static bool include_idle = true;
  44
  45 /* If true, display a line at the top describing each field. */
  46 static bool include_heading = true;
  47
  48 /* if true, display the user's full name from pw_gecos. */
  49 static bool include_fullname = true;
  50
  51 /* if true, display the user's ~/.project file when doing long format. */
  52 static bool include_project = true;
  53
  54 /* if true, display the user's ~/.plan file when doing long format. */
  55 static bool include_plan = true;
  56
  57 /* if true, display the user's home directory and shell
  58    when doing long format. */
  59 static bool include_home_and_shell = true;
  60
  61 /* if true, use the "short" output format. */
  62 static bool do_short_format = true;
  63
  64 /* If true, attempt to canonicalize hostnames via a DNS lookup. */
  65 static bool do_lookup;
  66
  67 /* if true, display the ut_host field. */
  68 #if HAVE_STRUCT_XTMP_UT_HOST
  69 static bool include_where = true;
  70 #endif
  71
  72 /* The strftime format to use for login times, and its expected
  73    output width.  */
  74 static char const *time_format;
  75 static int time_format_width;
  76
  77 /* for long options with no corresponding short option, use enum */
  78 enum
  79 {
  80   LOOKUP_OPTION = CHAR_MAX + 1
  81 };
  82
  83 static struct option const longopts[] =
  84 {
  85   {"lookup", no_argument, nullptr, LOOKUP_OPTION},
  86   {GETOPT_HELP_OPTION_DECL},
  87   {GETOPT_VERSION_OPTION_DECL},
  88   {nullptr, 0, nullptr, 0}
  89 };
  90
  91 /* Count and return the number of ampersands in STR.  */
  92
  93 ATTRIBUTE_PURE
  94 static idx_t
  95 count_ampersands (char const *str)
  96 {
  97   idx_t count = 0;
  98   for (; *str; str++)
  99     count += *str == '&';
 100   return count;
 101 }
 102
 103 /* Create a string (via xmalloc) which contains a full name by substituting
 104    for each ampersand in GECOS_NAME the USER_NAME string with its first
 105    character capitalized.  The caller must ensure that GECOS_NAME contains
 106    no ','s.  The caller also is responsible for free'ing the return value of
 107    this function.  */
 108
 109 static char *
 110 create_fullname (char const *gecos_name, char const *user_name)
 111 {
 112   idx_t rsize = strlen (gecos_name) + 1;
 113   char *result;
 114   char *r;
 115   idx_t ampersands = count_ampersands (gecos_name);
 116
 117   if (ampersands != 0)
 118     {
 119       idx_t ulen = strlen (user_name);
 120       ptrdiff_t product;
 121       if (ckd_mul (&product, ulen - 1, ampersands)
 122           || ckd_add (&rsize, rsize, product))
 123         xalloc_die ();
 124     }
 125
 126   r = result = xmalloc (rsize);
 127
 128   while (*gecos_name)
 129     {
 130       if (*gecos_name == '&')
 131         {
 132           char const *uname = user_name;
 133           if (islower (to_uchar (*uname)))
 134             *r++ = toupper (to_uchar (*uname++));
 135           while (*uname)
 136             *r++ = *uname++;
 137         }
 138       else
 139         {
 140           *r++ = *gecos_name;
 141         }
 142
 143       gecos_name++;
 144     }
 145   *r = 0;
 146
 147   return result;
 148 }
 149
 150 /* Return a string representing the time between WHEN and the time
 151    that this function is first run. */
 152
 153 static char const *
 154 idle_string (time_t when)
 155 {
 156   static time_t now = 0;
 157   static char buf[INT_STRLEN_BOUND (intmax_t) + sizeof "d"];
 158   time_t seconds_idle;
 159
 160   if (now == 0)
 161     time (&now);
 162
 163   seconds_idle = now - when;
 164   if (seconds_idle < 60)        /* One minute. */
 165     return "     ";
 166   if (seconds_idle < (24 * 60 * 60))    /* One day. */
 167     {
 168       int hours = seconds_idle / (60 * 60);
 169       int minutes = (seconds_idle % (60 * 60)) / 60;
 170       sprintf (buf, "%02d:%02d", hours, minutes);
 171     }
 172   else
 173     {
 174       intmax_t days = seconds_idle / (24 * 60 * 60);
 175       sprintf (buf, "%jdd", days);
 176     }
 177   return buf;
 178 }
 179
 180 /* Return a time string.  */
 181 static char const *
 182 time_string (struct gl_utmp const *utmp_ent)
 183 {
 184   static char buf[INT_STRLEN_BOUND (intmax_t) + sizeof "-%m-%d %H:%M"];
 185   struct tm *tmp = localtime (&utmp_ent->ut_ts.tv_sec);
 186
 187   if (tmp)
 188     {
 189       strftime (buf, sizeof buf, time_format, tmp);
 190       return buf;
 191     }
 192   else
 193     return timetostr (utmp_ent->ut_ts.tv_sec, buf);
 194 }
 195
 196 /* Display a line of information about UTMP_ENT. */
 197
 198 static void
 199 print_entry (struct gl_utmp const *utmp_ent)
 200 {
 201   struct stat stats;
 202   time_t last_change;
 203   char mesg;
 204
 205   /* If ut_line contains a space, the device name starts after the space.  */
 206   char *line = utmp_ent->ut_line;
 207   char *space = strchr (line, ' ');
 208   line = space ? space + 1 : line;
 209
 210   int dirfd;
 211   if (IS_ABSOLUTE_FILE_NAME (line))
 212     dirfd = AT_FDCWD;
 213   else
 214     {
 215       static int dev_dirfd;
 216       if (!dev_dirfd)
 217         {
 218           dev_dirfd = open ("/dev", O_PATHSEARCH | O_DIRECTORY);
 219           if (dev_dirfd < 0)
 220             dev_dirfd = AT_FDCWD - 1;
 221         }
 222       dirfd = dev_dirfd;
 223     }
 224
 225   if (AT_FDCWD <= dirfd && fstatat (dirfd, line, &stats, 0) == 0)
 226     {
 227       mesg = (stats.st_mode & S_IWGRP) ? ' ' : '*';
 228       last_change = stats.st_atime;
 229     }
 230   else
 231     {
 232       mesg = '?';
 233       last_change = 0;
 234     }
 235
 236   char *ut_user = utmp_ent->ut_user;
 237   if (strnlen (ut_user, 8) < 8)
 238     printf ("%-8s", ut_user);
 239   else
 240     fputs (ut_user, stdout);
 241
 242   if (include_fullname)
 243     {
 244       struct passwd *pw = getpwnam (ut_user);
 245       if (pw == nullptr)
 246         /* TRANSLATORS: Real name is unknown; at most 19 characters. */
 247         printf (" %19s", _("        ???"));
 248       else
 249         {
 250           char *const comma = strchr (pw->pw_gecos, ',');
 251           char *result;
 252
 253           if (comma)
 254             *comma = '\0';
 255
 256           result = create_fullname (pw->pw_gecos, pw->pw_name);
 257           printf (" %-19.19s", result);
 258           free (result);
 259         }
 260     }
 261
 262   fputc (' ', stdout);
 263   fputc (mesg, stdout);
 264   if (strnlen (utmp_ent->ut_line, 8) < 8)
 265     printf ("%-8s", utmp_ent->ut_line);
 266   else
 267     fputs (utmp_ent->ut_line, stdout);
 268
 269   if (include_idle)
 270     {
 271       if (last_change)
 272         printf (" %-6s", idle_string (last_change));
 273       else
 274         /* TRANSLATORS: Idle time is unknown; at most 5 characters. */
 275         printf (" %-6s", _("?????"));
 276     }
 277
 278   printf (" %s", time_string (utmp_ent));
 279
 280 #ifdef HAVE_STRUCT_XTMP_UT_HOST
 281   if (include_where && utmp_ent->ut_host[0])
 282     {
 283       char *host = nullptr;
 284       char *display = nullptr;
 285       char *ut_host = utmp_ent->ut_host;
 286
 287       /* Look for an X display.  */
 288       display = strchr (ut_host, ':');
 289       if (display)
 290         *display++ = '\0';
 291
 292       if (*ut_host && do_lookup)
 293         /* See if we can canonicalize it.  */
 294         host = canon_host (ut_host);
 295       if ( ! host)
 296         host = ut_host;
 297
 298       fputc (' ', stdout);
 299       fputs (host, stdout);
 300       if (display)
 301         {
 302           fputc (':', stdout);
 303           fputs (display, stdout);
 304         }
 305
 306       if (host != ut_host)
 307         free (host);
 308     }
 309 #endif
 310
 311   putchar ('\n');
 312 }
 313
 314 /* Display a verbose line of information about UTMP_ENT. */
 315
 316 static void
 317 print_long_entry (const char name[])
 318 {
 319   struct passwd *pw;
 320
 321   pw = getpwnam (name);
 322
 323   printf (_("Login name: "));
 324   printf ("%-28s", name);
 325
 326   printf (_("In real life: "));
 327   if (pw == nullptr)
 328     {
 329       /* TRANSLATORS: Real name is unknown; no hard limit. */
 330       printf (" %s", _("???\n"));
 331       return;
 332     }
 333   else
 334     {
 335       char *const comma = strchr (pw->pw_gecos, ',');
 336       char *result;
 337
 338       if (comma)
 339         *comma = '\0';
 340
 341       result = create_fullname (pw->pw_gecos, pw->pw_name);
 342       printf (" %s", result);
 343       free (result);
 344     }
 345
 346   putchar ('\n');
 347
 348   if (include_home_and_shell)
 349     {
 350       printf (_("Directory: "));
 351       printf ("%-29s", pw->pw_dir);
 352       printf (_("Shell: "));
 353       printf (" %s", pw->pw_shell);
 354       putchar ('\n');
 355     }
 356
 357   if (include_project)
 358     {
 359       FILE *stream;
 360       char buf[1024];
 361       char const *const baseproject = "/.project";
 362       char *const project =
 363         xmalloc (strlen (pw->pw_dir) + strlen (baseproject) + 1);
 364       stpcpy (stpcpy (project, pw->pw_dir), baseproject);
 365
 366       stream = fopen (project, "r");
 367       if (stream)
 368         {
 369           size_t bytes;
 370
 371           printf (_("Project: "));
 372
 373           while ((bytes = fread (buf, 1, sizeof (buf), stream)) > 0)
 374             fwrite (buf, 1, bytes, stdout);
 375           fclose (stream);
 376         }
 377
 378       free (project);
 379     }
 380
 381   if (include_plan)
 382     {
 383       FILE *stream;
 384       char buf[1024];
 385       char const *const baseplan = "/.plan";
 386       char *const plan =
 387         xmalloc (strlen (pw->pw_dir) + strlen (baseplan) + 1);
 388       stpcpy (stpcpy (plan, pw->pw_dir), baseplan);
 389
 390       stream = fopen (plan, "r");
 391       if (stream)
 392         {
 393           size_t bytes;
 394
 395           printf (_("Plan:\n"));
 396
 397           while ((bytes = fread (buf, 1, sizeof (buf), stream)) > 0)
 398             fwrite (buf, 1, bytes, stdout);
 399           fclose (stream);
 400         }
 401
 402       free (plan);
 403     }
 404
 405   putchar ('\n');
 406 }
 407
 408 /* Print the username of each valid entry and the number of valid entries
 409    in UTMP_BUF, which should have N elements. */
 410
 411 static void
 412 print_heading (void)
 413 {
 414   printf ("%-8s", _("Login"));
 415   if (include_fullname)
 416     printf (" %-19s", _("Name"));
 417   printf (" %-9s", _(" TTY"));
 418   if (include_idle)
 419     printf (" %-6s", _("Idle"));
 420   printf (" %-*s", time_format_width, _("When"));
 421 #ifdef HAVE_STRUCT_XTMP_UT_HOST
 422   if (include_where)
 423     printf (" %s", _("Where"));
 424 #endif
 425   putchar ('\n');
 426 }
 427
 428 /* Display UTMP_BUF, which should have N entries. */
 429
 430 static void
 431 scan_entries (idx_t n, struct gl_utmp const *utmp_buf,
 432               const int argc_names, char *const argv_names[])
 433 {
 434   if (hard_locale (LC_TIME))
 435     {
 436       time_format = "%Y-%m-%d %H:%M";
 437       time_format_width = 4 + 1 + 2 + 1 + 2 + 1 + 2 + 1 + 2;
 438     }
 439   else
 440     {
 441       time_format = "%b %e %H:%M";
 442       time_format_width = 3 + 1 + 2 + 1 + 2 + 1 + 2;
 443     }
 444
 445   if (include_heading)
 446     print_heading ();
 447
 448   while (n--)
 449     {
 450       if (IS_USER_PROCESS (utmp_buf))
 451         {
 452           if (argc_names)
 453             {
 454               for (int i = 0; i < argc_names; i++)
 455                 if (STREQ (utmp_buf->ut_user, argv_names[i]))
 456                   {
 457                     print_entry (utmp_buf);
 458                     break;
 459                   }
 460             }
 461           else
 462             print_entry (utmp_buf);
 463         }
 464       utmp_buf++;
 465     }
 466 }
 467
 468 /* Display a list of who is on the system, according to utmp file FILENAME. */
 469
 470 static void
 471 short_pinky (char const *filename,
 472              const int argc_names, char *const argv_names[])
 473 {
 474   idx_t n_users;
 475   struct gl_utmp *utmp_buf;
 476   if (read_utmp (filename, &n_users, &utmp_buf, READ_UTMP_USER_PROCESS) != 0)
 477     error (EXIT_FAILURE, errno, "%s", quotef (filename));
 478
 479   scan_entries (n_users, utmp_buf, argc_names, argv_names);
 480   exit (EXIT_SUCCESS);
 481 }
 482
 483 static void
 484 long_pinky (const int argc_names, char *const argv_names[])
 485 {
 486   for (int i = 0; i < argc_names; i++)
 487     print_long_entry (argv_names[i]);
 488 }
 489
 490 void
 491 usage (int status)
 492 {
 493   if (status != EXIT_SUCCESS)
 494     emit_try_help ();
 495   else
 496     {
 497       printf (_("Usage: %s [OPTION]... [USER]...\n"), program_name);
 498       fputs (_("\
 499 \n\
 500   -l              produce long format output for the specified USERs\n\
 501   -b              omit the user's home directory and shell in long format\n\
 502   -h              omit the user's project file in long format\n\
 503   -p              omit the user's plan file in long format\n\
 504   -s              do short format output, this is the default\n\
 505 "), stdout);
 506       fputs (_("\
 507   -f              omit the line of column headings in short format\n\
 508   -w              omit the user's full name in short format\n\
 509   -i              omit the user's full name and remote host in short format\n\
 510   -q              omit the user's full name, remote host and idle time\n\
 511                   in short format\n\
 512 "), stdout);
 513       fputs (_("\
 514       --lookup    attempt to canonicalize hostnames via DNS\n\
 515 "), stdout);
 516       fputs (HELP_OPTION_DESCRIPTION, stdout);
 517       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 518       printf (_("\
 519 \n\
 520 A lightweight 'finger' program;  print user information.\n\
 521 The utmp file will be %s.\n\
 522 "), UTMP_FILE);
 523       emit_ancillary_info (PROGRAM_NAME);
 524     }
 525   exit (status);
 526 }
 527
 528 int
 529 main (int argc, char **argv)
 530 {
 531   int optc;
 532   int n_users;
 533
 534   initialize_main (&argc, &argv);
 535   set_program_name (argv[0]);
 536   setlocale (LC_ALL, "");
 537   bindtextdomain (PACKAGE, LOCALEDIR);
 538   textdomain (PACKAGE);
 539
 540   atexit (close_stdout);
 541
 542   while ((optc = getopt_long (argc, argv, "sfwiqbhlp", longopts, nullptr))
 543          != -1)
 544     {
 545       switch (optc)
 546         {
 547         case 's':
 548           do_short_format = true;
 549           break;
 550
 551         case 'l':
 552           do_short_format = false;
 553           break;
 554
 555         case 'f':
 556           include_heading = false;
 557           break;
 558
 559         case 'w':
 560           include_fullname = false;
 561           break;
 562
 563         case 'i':
 564           include_fullname = false;
 565 #ifdef HAVE_STRUCT_XTMP_UT_HOST
 566           include_where = false;
 567 #endif
 568           break;
 569
 570         case 'q':
 571           include_fullname = false;
 572 #ifdef HAVE_STRUCT_XTMP_UT_HOST
 573           include_where = false;
 574 #endif
 575           include_idle = false;
 576           break;
 577
 578         case 'h':
 579           include_project = false;
 580           break;
 581
 582         case 'p':
 583           include_plan = false;
 584           break;
 585
 586         case 'b':
 587           include_home_and_shell = false;
 588           break;
 589
 590         case LOOKUP_OPTION:
 591           do_lookup = true;
 592           break;
 593
 594         case_GETOPT_HELP_CHAR;
 595
 596         case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 597
 598         default:
 599           usage (EXIT_FAILURE);
 600         }
 601     }
 602
 603   n_users = argc - optind;
 604
 605   if (!do_short_format && n_users == 0)
 606     {
 607       error (0, 0, _("no username specified; at least one must be\
 608  specified when using -l"));
 609       usage (EXIT_FAILURE);
 610     }
 611
 612   if (do_short_format)
 613     short_pinky (UTMP_FILE, n_users, argv + optind);
 614   else
 615     long_pinky (n_users, argv + optind);
 616
 617   return EXIT_SUCCESS;
 618 }