who: fix attempts to open '/dev/dev/ttyX'; make columns a bit wider, add -H

function                                             old     new   delta
who_main                                             292     363     +71

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 32 insertions, 19 deletions

diff --git a/coreutils/who.c b/coreutils/who.c
index 85a0025c3..dfbb4c046 100644
--- a/coreutils/who.c
+++ b/coreutils/who.c
@@ -42,35 +42,47 @@ static void idle_string(char *str6, time_t t)
 int who_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int who_main(int argc UNUSED_PARAM, char **argv)
 {
-        char str6[6];
         struct utmp *ut;
-        struct stat st;
-        char *name;
         unsigned opt;
 
         opt_complementary = "=0";
-        opt = getopt32(argv, "a");
+        opt = getopt32(argv, "aH");
+        if (opt & 2) // -H
+                printf("USER\t\tTTY\t\tIDLE\tTIME\t\t HOST\n");
 
         setutent();
-        printf("USER       TTY      IDLE      TIME            HOST\n");
         while ((ut = getutent()) != NULL) {
-                if (ut->ut_user[0] && (opt || ut->ut_type == USER_PROCESS)) {
-                        time_t tmp;
-                        /* ut->ut_line is device name of tty - "/dev/" */
-                        name = concat_path_file("/dev", ut->ut_line);
+                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;
+
                         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 */
-                        tmp = ut->ut_tv.tv_sec;
-                        /* 15 chars for time:   Nov 10 19:33:20 */
-                        printf("%-10s %-8s %-9s %-15.15s %s\n",
-                                        ut->ut_user, ut->ut_line, str6,
-                                        ctime(&tmp) + 4, ut->ut_host);
-                        if (ENABLE_FEATURE_CLEAN_UP)
-                                free(name);
+                        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
+                        );
                 }
         }
         if (ENABLE_FEATURE_CLEAN_UP)
diff --git a/loginutils/login.c b/loginutils/login.c
index b5e348b66..256c7c475 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -61,7 +61,7 @@ static void read_or_build_utent(struct utmp *utptr, int run_by_root)
 
         /* First, try to find a valid utmp entry for this process.  */
         /* If there is one, just use it.  */
-        while ((ut = getutent()) != NULL)
+        while ((ut = getutent()) != NULL) {
                 if (ut->ut_pid == pid && ut->ut_line[0] && ut->ut_id[0]
                  && (ut->ut_type == LOGIN_PROCESS || ut->ut_type == USER_PROCESS)
                 ) {
@@ -70,6 +70,7 @@ static void read_or_build_utent(struct utmp *utptr, int run_by_root)
                                 memset(utptr->ut_host, 0, sizeof(utptr->ut_host));
                         return;
                 }
+        }
 
 // Why? Do we require non-root to exec login from another
 // former login process (e.g. login shell)? Some login's have
diff --git a/networking/telnetd.c b/networking/telnetd.c
index dd59de9d4..cab94f0f7 100644
--- a/networking/telnetd.c
+++ b/networking/telnetd.c
@@ -74,11 +74,11 @@ struct globals {
    string of characters fit for the terminal.  Do this by packing
    all characters meant for the terminal sequentially towards the end of buf.
 
-   Return a pointer to the beginning of the characters meant for the terminal.
+   Return a pointer to the beginning of the characters meant for the terminal
    and make *num_totty the number of characters that should be sent to
    the terminal.
 
-   Note - If an IAC (3 byte quantity) starts before (bf + len) but extends
+   Note - if an IAC (3 byte quantity) starts before (bf + len) but extends
    past (bf + len) then that IAC will be left unprocessed and *processed
    will be less than len.