users: new applet.

Signed-off-by: Tito Ragusa <farmatito@tiscali.it>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 62 insertions, 35 deletions

diff --git a/coreutils/Config.src b/coreutils/Config.src
index 9aa04e946..65165d79b 100644
--- a/coreutils/Config.src
+++ b/coreutils/Config.src
@@ -725,13 +725,6 @@ config FEATURE_WC_LARGE
         help
           Use "unsigned long long" in wc for counter variables.
 
-config WHO
-        bool "who"
-        default y
-        depends on FEATURE_UTMP
-        help
-          who is used to show who is logged on.
-
 config WHOAMI
         bool "whoami"
         default y
diff --git a/coreutils/who.c b/coreutils/who.c
index 9f37f65fd..c6c925264 100644
--- a/coreutils/who.c
+++ b/coreutils/who.c
@@ -18,6 +18,31 @@
  */
 /* BB_AUDIT SUSv3 _NOT_ compliant -- missing options -b, -d, -l, -m, -p, -q, -r, -s, -t, -T, -u; Missing argument 'file'.  */
 
+//config:config WHO
+//config:      bool "who"
+//config:      default y
+//config:      depends on FEATURE_UTMP
+//config:      help
+//config:        who is used to show who is logged on.
+
+//config:config USERS
+//config:      bool "users"
+//config:      default y
+//config:      depends on FEATURE_UTMP
+//config:      help
+//config:        Print users currently logged on.
+
+//applet:IF_USERS(APPLET_ODDNAME(users, who, BB_DIR_USR_BIN, BB_SUID_DROP, users))
+//applet:IF_WHO(  APPLET(  who, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_USERS) += who.o
+//kbuild:lib-$(CONFIG_WHO) += who.o
+
+//usage:#define users_trivial_usage
+//usage:       ""
+//usage:#define users_full_usage "\n\n"
+//usage:       "Print the users currently logged on"
+
 //usage:#define who_trivial_usage
 //usage:       "[-a]"
 //usage:#define who_full_usage "\n\n"
@@ -49,9 +74,11 @@ int who_main(int argc UNUSED_PARAM, char **argv)
 {
         struct utmp *ut;
         unsigned opt;
+        int do_users = (ENABLE_USERS && (!ENABLE_WHO || applet_name[0] == 'u'));
+        const char *fmt = "%s";
 
         opt_complementary = "=0";
-        opt = getopt32(argv, "aH");
+        opt = getopt32(argv, do_users ? "" : "aH");
         if (opt & 2) // -H
                 printf("USER\t\tTTY\t\tIDLE\tTIME\t\t HOST\n");
 
@@ -60,36 +87,43 @@ int who_main(int argc UNUSED_PARAM, char **argv)
                 if (ut->ut_user[0]
                  && ((opt & 1) || ut->ut_type == USER_PROCESS)
                 ) {
-                        char str6[6];
-                        char name[sizeof("/dev/") + sizeof(ut->ut_line) + 1];
-                        struct stat st;
-                        time_t seconds;
+                        if (!do_users) {
+                                char str6[6];
+                                char name[sizeof("/dev/") + sizeof(ut->ut_line) + 1];
+                                struct stat st;
+                                time_t seconds;
 
-                        str6[0] = '?';
-                        str6[1] = '\0';
-                        strcpy(name, "/dev/");
-                        safe_strncpy(ut->ut_line[0] == '/' ? name : name + sizeof("/dev/")-1,
-                                ut->ut_line,
-                                sizeof(ut->ut_line)+1
-                        );
-                        if (stat(name, &st) == 0)
-                                idle_string(str6, st.st_atime);
-                        /* manpages say ut_tv.tv_sec *is* time_t,
-                         * but some systems have it wrong */
-                        seconds = ut->ut_tv.tv_sec;
-                        /* How wide time field can be?
-                         * "Nov 10 19:33:20": 15 chars
-                         * "2010-11-10 19:33": 16 chars
-                         */
-                        printf("%-15.*s %-15.*s %-7s %-16.16s %.*s\n",
-                                        (int)sizeof(ut->ut_user), ut->ut_user,
-                                        (int)sizeof(ut->ut_line), ut->ut_line,
-                                        str6,
-                                        ctime(&seconds) + 4,
-                                        (int)sizeof(ut->ut_host), ut->ut_host
-                        );
+                                str6[0] = '?';
+                                str6[1] = '\0';
+                                strcpy(name, "/dev/");
+                                safe_strncpy(ut->ut_line[0] == '/' ? name : name + sizeof("/dev/")-1,
+                                        ut->ut_line,
+                                        sizeof(ut->ut_line)+1
+                                );
+                                if (stat(name, &st) == 0)
+                                        idle_string(str6, st.st_atime);
+                                /* manpages say ut_tv.tv_sec *is* time_t,
+                                 * but some systems have it wrong */
+                                seconds = ut->ut_tv.tv_sec;
+                                /* How wide time field can be?
+                                 * "Nov 10 19:33:20": 15 chars
+                                 * "2010-11-10 19:33": 16 chars
+                                 */
+                                printf("%-15.*s %-15.*s %-7s %-16.16s %.*s\n",
+                                                (int)sizeof(ut->ut_user), ut->ut_user,
+                                                (int)sizeof(ut->ut_line), ut->ut_line,
+                                                str6,
+                                                ctime(&seconds) + 4,
+                                                (int)sizeof(ut->ut_host), ut->ut_host
+                                );
+                        } else {
+                                printf(fmt, ut->ut_user);
+                                fmt = " %s";
+                        }
                 }
         }
+        if (do_users)
+                bb_putchar('\n');
         if (ENABLE_FEATURE_CLEAN_UP)
                 endutent();
         return EXIT_SUCCESS;