kvm tools: Cleanup termios handling

This patch cleans up the confused termios handling to do what Lguest does.

Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/main.c b/tools/kvm/main.c
index 42857cdf018b8c63a5eda5561c83648058de3a49..643f6bde050584c5cafcefe0dc1c7b21a172b60b 100644 (file)
--- a/tools/kvm/main.c
+++ b/tools/kvm/main.c
@@ -29,46 +29,34 @@ static void usage(char *argv[])
 
 static struct kvm *kvm;
 
-static struct termios tty_origin_stdin;
-static struct termios tty_origin_stdout;
-static struct termios tty_origin_stderr;
+static struct termios orig_term;
 
-static void tty_save_origins(void)
+static void setup_console(void)
 {
-       tcgetattr(fileno(stdin), &tty_origin_stdin);
-       tcgetattr(fileno(stdout), &tty_origin_stdout);
-       tcgetattr(fileno(stderr), &tty_origin_stderr);
-}
+       struct termios term;
 
-static void tty_restore_origins(void)
-{
-       tcsetattr(fileno(stdin), TCSAFLUSH, &tty_origin_stdin);
-       tcsetattr(fileno(stdout), TCSAFLUSH, &tty_origin_stdout);
-       tcsetattr(fileno(stderr), TCSAFLUSH, &tty_origin_stderr);
+       if (tcgetattr(STDIN_FILENO, &orig_term) < 0)
+               die("unable to save initial standard input settings");
+
+       term                    = orig_term;
+
+       term.c_lflag            &= ~(ICANON|ECHO);
+
+       tcsetattr(STDIN_FILENO, TCSANOW, &term);
 }
 
-static void tty_set_canon_flag(int fd, int on)
+static void cleanup_console(void)
 {
-       struct termios tty;
-       int mask = ISTRIP | INLCR | ICRNL | IGNCR | IXON | IXOFF | ICANON | ECHO;
-
-       tcgetattr(fd, &tty);
-       if (on)
-               tty.c_lflag |= mask;
-       else
-               tty.c_lflag &= ~mask;
-       tcsetattr(fd, TCSAFLUSH, &tty);
+       tcsetattr(STDIN_FILENO, TCSANOW, &orig_term);
 }
 
 static void shutdown(void)
 {
-       tty_set_canon_flag(fileno(stdin), 0);
-       tty_restore_origins();
+       cleanup_console();
 }
 
 static void handle_sigint(int sig)
 {
-       shutdown();
        exit(1);
 }
 
@@ -101,13 +89,13 @@ int main(int argc, char *argv[])
        bool single_step = false;
        int i;
 
-       tty_save_origins();
-
-       atexit(shutdown);
-
        signal(SIGQUIT, handle_sigquit);
        signal(SIGINT, handle_sigint);
 
+       setup_console();
+
+       atexit(shutdown);
+
        for (i = 1; i < argc; i++) {
                if (option_matches(argv[i], "--kernel=")) {
                        kernel_filename = &argv[i][9];
@@ -183,8 +171,6 @@ int main(int argc, char *argv[])
 
        kvm__start_timer(kvm);
 
-       tty_set_canon_flag(fileno(stdin), 1);
-
        for (;;) {
                kvm__run(kvm);