telnetd: code shrink suggested by Ralf Friedl <Ralf.Friedl@online.de>

diff --git a/networking/telnetd.c b/networking/telnetd.c
index eb3701133b1171af50085acc00baccd3477708aa..f06bff8b95f4827019ad7801b3a16a8762bc86eb 100644 (file)
--- a/networking/telnetd.c
+++ b/networking/telnetd.c
@@ -203,7 +203,7 @@ getpty(char *line, int size)
 
 static struct tsession *
 make_new_session(
-               USE_FEATURE_TELNETD_STANDALONE(int sock_r, int sock_w)
+               USE_FEATURE_TELNETD_STANDALONE(int sock)
                SKIP_FEATURE_TELNETD_STANDALONE(void)
 ) {
        const char *login_argv[2];
@@ -221,19 +221,22 @@ make_new_session(
                bb_error_msg("can't create pty");
                return NULL;
        }
-       if (fd > maxfd) maxfd = fd;
+       if (fd > maxfd)
+               maxfd = fd;
        ts->ptyfd = fd;
        ndelay_on(fd);
 #if ENABLE_FEATURE_TELNETD_STANDALONE
-       if (sock_w > maxfd) maxfd = sock_w;
-       ts->sockfd_write = sock_w;
-       ndelay_on(sock_w);
-       if (sock_r > maxfd) maxfd = sock_r;
-       ts->sockfd_read = sock_r;
-       ndelay_on(sock_r);
+       ts->sockfd_read = sock;
+       ndelay_on(sock);
+       if (!sock) /* We are called with fd 0 - we are in inetd mode */
+               sock++;
+       ts->sockfd_write = sock;
+       ndelay_on(sock);
+       if (sock > maxfd)
+               maxfd = sock;
 #else
-       ts->sockfd_write = 1;
        /* ts->sockfd_read = 0; - done by xzalloc */
+       ts->sockfd_write = 1;
        ndelay_on(0);
        ndelay_on(1);
 #endif
@@ -326,27 +329,33 @@ free_session(struct tsession *ts)
                t->next = ts->next;
        }
 
+#if 0
        /* It was said that "normal" telnetd just closes ptyfd,
         * doesn't send SIGKILL. When we close ptyfd,
         * kernel sends SIGHUP to processes having slave side opened. */
-       /*kill(ts->shell_pid, SIGKILL);
-       wait4(ts->shell_pid, NULL, 0, NULL);*/
+       kill(ts->shell_pid, SIGKILL);
+       wait4(ts->shell_pid, NULL, 0, NULL);
+#endif
        close(ts->ptyfd);
        close(ts->sockfd_read);
-       /* error if ts->sockfd_read == ts->sockfd_write. So what? ;) */
-       close(ts->sockfd_write);
+       /* We do not need to close(ts->sockfd_write), it's the same
+        * as sockfd_read unless we are in inetd mode. But in inetd mode
+        * we do not free_session(), ever */
        free(ts);
 
        /* Scan all sessions and find new maxfd */
-       ts = sessions;
        maxfd = 0;
+       ts = sessions;
        while (ts) {
                if (maxfd < ts->ptyfd)
                        maxfd = ts->ptyfd;
                if (maxfd < ts->sockfd_read)
                        maxfd = ts->sockfd_read;
+#if 0
+               /* Again, sockfd_write == sockfd_read here */
                if (maxfd < ts->sockfd_write)
                        maxfd = ts->sockfd_write;
+#endif
                ts = ts->next;
        }
 }
@@ -434,7 +443,7 @@ int telnetd_main(int argc, char **argv)
 
 #if ENABLE_FEATURE_TELNETD_STANDALONE
        if (IS_INETD) {
-               sessions = make_new_session(0, 1);
+               sessions = make_new_session(0);
                if (!sessions) /* pty opening or vfork problem, exit */
                        return 1; /* make_new_session prints error message */
        } else {
@@ -519,7 +528,7 @@ int telnetd_main(int argc, char **argv)
                if (fd < 0)
                        goto again;
                /* Create a new session and link it into our active list */
-               new_ts = make_new_session(fd, fd);
+               new_ts = make_new_session(fd);
                if (new_ts) {
                        new_ts->next = sessions;
                        sessions = new_ts;
@@ -545,9 +554,7 @@ int telnetd_main(int argc, char **argv)
                                        goto skip1;
                                if (IS_INETD)
                                        return 0;
-                               free_session(ts);
-                               ts = next;
-                               continue;
+                               goto kill_session;
                        }
                        ts->size1 -= count;
                        ts->wridx1 += count;
@@ -564,9 +571,7 @@ int telnetd_main(int argc, char **argv)
                                        goto skip2;
                                if (IS_INETD)
                                        return 0;
-                               free_session(ts);
-                               ts = next;
-                               continue;
+                               goto kill_session;
                        }
                        ts->size2 -= count;
                        ts->wridx2 += count;
@@ -577,7 +582,7 @@ int telnetd_main(int argc, char **argv)
                /* Should not be needed, but... remove_iacs is actually buggy
                 * (it cannot process iacs which wrap around buffer's end)!
                 * Since properly fixing it requires writing bigger code,
-                * we will rely instead on this code making it virtually impossible
+                * we rely instead on this code making it virtually impossible
                 * to have wrapped iac (people don't type at 2k/second).
                 * It also allows for bigger reads in common case. */
                if (ts->size1 == 0) {
@@ -598,14 +603,11 @@ int telnetd_main(int argc, char **argv)
                                        goto skip3;
                                if (IS_INETD)
                                        return 0;
-                               free_session(ts);
-                               ts = next;
-                               continue;
+                               goto kill_session;
                        }
                        /* Ignore trailing NUL if it is there */
                        if (!TS_BUF1[ts->rdidx1 + count - 1]) {
-                               if (!--count)
-                                       goto skip3;
+                               --count;
                        }
                        ts->size1 += count;
                        ts->rdidx1 += count;
@@ -622,9 +624,7 @@ int telnetd_main(int argc, char **argv)
                                        goto skip4;
                                if (IS_INETD)
                                        return 0;
-                               free_session(ts);
-                               ts = next;
-                               continue;
+                               goto kill_session;
                        }
                        ts->size2 += count;
                        ts->rdidx2 += count;
@@ -633,6 +633,11 @@ int telnetd_main(int argc, char **argv)
                }
  skip4:
                ts = next;
+               continue;
+ kill_session:
+               free_session(ts);
+               ts = next;
        }
+
        goto again;
 }