.

src/who.c

@@ -0,0 +1,451 @@
+/* GNU's who.
+   Copyright (C) 92, 93, 94, 95, 96, 1997 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+/* Written by jla; revised by djm */
+
+/* Output format:
+   name [state] line time [idle] host
+   state: -T
+   name, line, time: not -q
+   idle: -u
+*/
+
+#include <config.h>
+#include <getopt.h>
+
+#include "system.h"
+#include "error.h"
+#include "readutmp.h"
+
+#ifndef MAXHOSTNAMELEN
+# define MAXHOSTNAMELEN 64
+#endif
+
+#ifndef S_IWGRP
+# define S_IWGRP 020
+#endif
+
+int gethostname ();
+char *ttyname ();
+char *xmalloc ();
+
+/* The name this program was run with. */
+char *program_name;
+
+/* If nonzero, display usage information and exit.  */
+static int show_help;
+
+/* If nonzero, print the version on standard output and exit.  */
+static int show_version;
+
+/* If nonzero, display only a list of usernames and count of
+   the users logged on.
+   Ignored for `who am i'. */
+static int short_list;
+
+/* If nonzero, display the hours:minutes since each user has touched
+   the keyboard, or "." if within the last minute, or "old" if
+   not within the last day. */
+static int include_idle;
+
+/* If nonzero, display a line at the top describing each field. */
+static int include_heading;
+
+/* If nonzero, display a `+' for each user if mesg y, a `-' if mesg n,
+   or a `?' if their tty cannot be statted. */
+static int include_mesg;
+
+static struct option const longopts[] =
+{
+  {"count", no_argument, NULL, 'q'},
+  {"idle", no_argument, NULL, 'u'},
+  {"heading", no_argument, NULL, 'H'},
+  {"message", no_argument, NULL, 'T'},
+  {"mesg", no_argument, NULL, 'T'},
+  {"writable", no_argument, NULL, 'T'},
+  {"help", no_argument, &show_help, 1},
+  {"version", no_argument, &show_version, 1},
+  {NULL, 0, NULL, 0}
+};
+
+/* Return a string representing the time between WHEN and the time
+   that this function is first run. */
+
+static const char *
+idle_string (time_t when)
+{
+  static time_t now = 0;
+  static char idle_hhmm[10];
+  time_t seconds_idle;
+
+  if (now == 0)
+    time (&now);
+
+  seconds_idle = now - when;
+  if (seconds_idle < 60)	/* One minute. */
+    return "  .  ";
+  if (seconds_idle < (24 * 60 * 60)) /* One day. */
+    {
+      sprintf (idle_hhmm, "%02d:%02d",
+	       (int) (seconds_idle / (60 * 60)),
+	       (int) ((seconds_idle % (60 * 60)) / 60));
+      return (const char *) idle_hhmm;
+    }
+  return _(" old ");
+}
+
+/* Display a line of information about entry THIS. */
+
+static void
+print_entry (STRUCT_UTMP *this)
+{
+  struct stat stats;
+  time_t last_change;
+  char mesg;
+
+#define DEV_DIR_WITH_TRAILING_SLASH "/dev/"
+#define DEV_DIR_LEN (sizeof (DEV_DIR_WITH_TRAILING_SLASH) - 1)
+
+  char line[sizeof (this->ut_line) + DEV_DIR_LEN + 1];
+  time_t tm;
+
+  /* Copy ut_line into LINE, prepending `/dev/' if ut_line is not
+     already an absolute pathname.  Some system may put the full,
+     absolute pathname in ut_line.  */
+  if (this->ut_line[0] == '/')
+    {
+      strncpy (line, this->ut_line, sizeof (this->ut_line));
+      line[sizeof (this->ut_line)] = '\0';
+    }
+  else
+    {
+      strcpy (line, DEV_DIR_WITH_TRAILING_SLASH);
+      strncpy (line + DEV_DIR_LEN, this->ut_line, sizeof (this->ut_line));
+      line[DEV_DIR_LEN + sizeof (this->ut_line)] = '\0';
+    }
+
+  if (stat (line, &stats) == 0)
+    {
+      mesg = (stats.st_mode & S_IWGRP) ? '+' : '-';
+      last_change = stats.st_atime;
+    }
+  else
+    {
+      mesg = '?';
+      last_change = 0;
+    }
+
+  printf ("%-8.*s", (int) sizeof (this->ut_name), this->ut_name);
+  if (include_mesg)
+    printf ("  %c  ", mesg);
+  printf (" %-8.*s", (int) sizeof (this->ut_line), this->ut_line);
+
+  /* Don't take the address of UT_TIME_MEMBER directly.
+     Ulrich Drepper wrote:
+     ``... GNU libc (and perhaps other libcs as well) have extended
+     utmp file formats which do not use a simple time_t ut_time field.
+     In glibc, ut_time is a macro which selects for backward compatibility
+     the tv_sec member of a struct timeval value.''  */
+  tm = UT_TIME_MEMBER (this);
+  printf (" %-12.12s", ctime (&tm) + 4);
+
+  if (include_idle)
+    {
+      if (last_change)
+	printf (" %s", idle_string (last_change));
+      else
+	printf ("   .  ");
+    }
+#ifdef HAVE_UT_HOST
+  if (this->ut_host[0])
+    {
+      extern char *canon_host ();
+      char ut_host[sizeof (this->ut_host) + 1];
+      char *host = 0, *display = 0;
+
+      /* Copy the host name into UT_HOST, and ensure it's nul terminated. */
+      strncpy (ut_host, this->ut_host, (int) sizeof (this->ut_host));
+      ut_host[sizeof (this->ut_host)] = '\0';
+
+      /* Look for an X display.  */
+      display = strrchr (ut_host, ':');
+      if (display)
+	*display++ = '\0';
+
+      if (*ut_host)
+	/* See if we can canonicalize it.  */
+	host = canon_host (ut_host);
+      if (! host)
+	host = ut_host;
+
+      if (display)
+	printf (" (%s:%s)", host, display);
+      else
+	printf (" (%s)", host);
+    }
+#endif
+
+  putchar ('\n');
+}
+
+/* Print the username of each valid entry and the number of valid entries
+   in `utmp_contents', which should have N elements. */
+
+static void
+list_entries_who (int n)
+{
+  register STRUCT_UTMP *this = utmp_contents;
+  int entries;
+
+  entries = 0;
+  while (n--)
+    {
+      if (this->ut_name[0]
+#ifdef USER_PROCESS
+	  && this->ut_type == USER_PROCESS
+#endif
+	 )
+	{
+	  char *trimmed_name;
+
+	  trimmed_name = extract_trimmed_name (this);
+
+	  printf ("%s ", trimmed_name);
+	  free (trimmed_name);
+	  entries++;
+	}
+      this++;
+    }
+  printf (_("\n# users=%u\n"), entries);
+}
+
+static void
+print_heading (void)
+{
+  printf ("%-8s ", _("USER"));
+  if (include_mesg)
+    printf (_("MESG "));
+  printf ("%-8s ", _("LINE"));
+  printf (_("LOGIN-TIME   "));
+  if (include_idle)
+    printf (_("IDLE  "));
+  printf (_("FROM\n"));
+}
+
+/* Display `utmp_contents', which should have N entries. */
+
+static void
+scan_entries (int n)
+{
+  register STRUCT_UTMP *this = utmp_contents;
+
+  if (include_heading)
+    print_heading ();
+
+  while (n--)
+    {
+      if (this->ut_name[0]
+#ifdef USER_PROCESS
+	  && this->ut_type == USER_PROCESS
+#endif
+	 )
+	print_entry (this);
+      this++;
+    }
+}
+
+/* Display a list of who is on the system, according to utmp file FILENAME. */
+
+static void
+who (const char *filename)
+{
+  int users = read_utmp (filename);
+  if (short_list)
+    list_entries_who (users);
+  else
+    scan_entries (users);
+}
+
+/* Search `utmp_contents', which should have N entries, for
+   an entry with a `ut_line' field identical to LINE.
+   Return the first matching entry found, or NULL if there
+   is no matching entry. */
+
+static STRUCT_UTMP *
+search_entries (int n, char *line)
+{
+  register STRUCT_UTMP *this = utmp_contents;
+
+  while (n--)
+    {
+      if (this->ut_name[0]
+#ifdef USER_PROCESS
+	  && this->ut_type == USER_PROCESS
+#endif
+	  && !strncmp (line, this->ut_line, sizeof (this->ut_line)))
+	return this;
+      this++;
+    }
+  return NULL;
+}
+
+/* Display the entry in utmp file FILENAME for this tty on standard input,
+   or nothing if there is no entry for it. */
+
+static void
+who_am_i (char *filename)
+{
+  register STRUCT_UTMP *utmp_entry;
+  char hostname[MAXHOSTNAMELEN + 1];
+  char *tty;
+
+  if (gethostname (hostname, MAXHOSTNAMELEN + 1))
+    *hostname = 0;
+
+  if (include_heading)
+    {
+      printf ("%*s ", (int) strlen (hostname), " ");
+      print_heading ();
+    }
+
+  tty = ttyname (0);
+  if (tty == NULL)
+    return;
+  tty += 5;			/* Remove "/dev/".  */
+
+  utmp_entry = search_entries (read_utmp (filename), tty);
+  if (utmp_entry == NULL)
+    return;
+
+  printf ("%s!", hostname);
+  print_entry (utmp_entry);
+}
+
+static void
+usage (int status)
+{
+  if (status != 0)
+    fprintf (stderr, _("Try `%s --help' for more information.\n"),
+	     program_name);
+  else
+    {
+      printf (_("Usage: %s [OPTION]... [ FILE | ARG1 ARG2 ]\n"), program_name);
+      printf (_("\
+\n\
+  -H, --heading     print line of column headings\n\
+  -i, -u, --idle    add user idle time as HOURS:MINUTES, . or old\n\
+  -m                only hostname and user associated with stdin\n\
+  -q, --count       all login names and number of users logged on\n\
+  -s                (ignored)\n\
+  -T, -w, --mesg    add user's message status as +, - or ?\n\
+      --message     same as -T\n\
+      --writable    same as -T\n\
+      --help        display this help and exit\n\
+      --version     output version information and exit\n\
+\n\
+If FILE is not specified, use %s.  %s as FILE is common.\n\
+If ARG1 ARG2 given, -m presumed: `am i' or `mom likes' are usual.\n\
+"), UTMP_FILE, WTMP_FILE);
+      puts (_("\nReport bugs to <sh-utils-bugs@gnu.ai.mit.edu>."));
+    }
+  exit (status);
+}
+
+int
+main (int argc, char **argv)
+{
+  int optc, longind;
+  int my_line_only = 0;
+
+  program_name = argv[0];
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  while ((optc = getopt_long (argc, argv, "imqsuwHT", longopts, &longind)) != -1)
+    {
+      switch (optc)
+	{
+	case 0:
+	  break;
+
+	case 'm':
+	  my_line_only = 1;
+	  break;
+
+	case 'q':
+	  short_list = 1;
+	  break;
+
+	case 's':
+	  break;
+
+	case 'i':
+	case 'u':
+	  include_idle = 1;
+	  break;
+
+	case 'H':
+	  include_heading = 1;
+	  break;
+
+	case 'w':
+	case 'T':
+	  include_mesg = 1;
+	  break;
+
+	default:
+	  usage (1);
+	}
+    }
+
+  if (show_version)
+    {
+      printf ("who (%s) %s\n", GNU_PACKAGE, VERSION);
+      exit (0);
+    }
+
+  if (show_help)
+    usage (0);
+
+  switch (argc - optind)
+    {
+    case 0:			/* who */
+      if (my_line_only)
+	who_am_i (UTMP_FILE);
+      else
+	who (UTMP_FILE);
+      break;
+
+    case 1:			/* who <utmp file> */
+      if (my_line_only)
+	who_am_i (argv[optind]);
+      else
+	who (argv[optind]);
+      break;
+
+    case 2:			/* who <blurf> <glop> */
+      who_am_i (UTMP_FILE);
+      break;
+
+    default:			/* lose */
+      error (0, 0, _("too many arguments"));
+      usage (1);
+    }
+
+  exit (0);
+}