set terminal settings when console is a tty

As the console output can be a tty, we want to have the terminal to
be set as a specific manner to not echo and receive signals from the
keyboard.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

diff --git a/src/lxc/conf.h b/src/lxc/conf.h
index 39cb0ecf6c045b7051280d14e1061f83edbed160..eede2b0869a9c8bfa1b6d8ddb24a6a748f9670c3 100644 (file)
--- a/src/lxc/conf.h
+++ b/src/lxc/conf.h
@@ -158,6 +158,7 @@ struct lxc_console {
        int master;
        int peer;
        char name[MAXPATHLEN];
+       struct termios *tios;
 };
 
 /*

diff --git a/src/lxc/console.c b/src/lxc/console.c
index 8e66665e61edb4a076788edf59a7bd1fdca93673..c14a38bc036fd9f56c7b9001999d82bc217e69c8 100644 (file)
--- a/src/lxc/console.c
+++ b/src/lxc/console.c
@@ -22,6 +22,7 @@
  */
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
@@ -140,6 +141,8 @@ out_close:
 
 int lxc_create_console(struct lxc_console *console)
 {
+       struct termios tios;
+
        if (openpty(&console->master, &console->slave,
                    console->name, NULL, NULL)) {
                SYSERROR("failed to allocate a pty");
@@ -156,7 +159,41 @@ int lxc_create_console(struct lxc_console *console)
                goto err;
        }
 
+       if (!isatty(console->peer))
+               return 0;
+
+       console->tios = malloc(sizeof(tios));
+       if (!console->tios) {
+               SYSERROR("failed to allocate memory");
+               goto err;
+       }
+
+       /* Get termios */
+       if (tcgetattr(console->peer, console->tios)) {
+               SYSERROR("failed to get current terminal settings");
+               goto err_free;
+       }
+
+       tios = *console->tios;
+
+       /* Remove the echo characters and signal reception, the echo
+        * will be done below with master proxying */
+       tios.c_iflag &= ~IGNBRK;
+       tios.c_iflag &= BRKINT;
+       tios.c_lflag &= ~(ECHO|ICANON|ISIG);
+       tios.c_cc[VMIN] = 1;
+       tios.c_cc[VTIME] = 0;
+
+       /* Set new attributes */
+       if (tcsetattr(console->peer, TCSAFLUSH, &tios)) {
+               ERROR("failed to set new terminal settings");
+               goto err_free;
+       }
+
        return 0;
+
+err_free:
+       free(console->tios);
 err:
        close(console->master);
        close(console->slave);
@@ -165,6 +202,9 @@ err:
 
 void lxc_delete_console(const struct lxc_console *console)
 {
+       if (console->tios &&
+           tcsetattr(console->peer, TCSAFLUSH, console->tios))
+               WARN("failed to set old terminal settings");
        close(console->master);
        close(console->slave);
 }