tty: Clear tty before login: prompt by default, add 'noclear' option

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

doc/config.md

@@ -136,7 +136,7 @@ Syntax:
 * `include <CONF>`  
   Include another configuration file.  Absolute path required.
 
-* `tty [LVLS] <DEV> [BAUD] [TERM]`  
+* `tty [LVLS] <DEV> [BAUD] [TERM] [noclear]`
   Start a getty on the given TTY device DEV, in the given runlevels.  If
   no tty setting is given in `finit.conf` no login is possible.  Use the
   `service` stanza to start a stand-alone shell for really bare bones

src/exec.c

@@ -38,7 +38,7 @@
 
 #define NUM_ARGS    16
 
-int getty(char *tty, char *baud, char *term, char *user);
+int getty(char *tty, char *baud, char *term, int noclear, char *user);
 
 
 /* Wait for process completion, returns status of waitpid(2) syscall */
@@ -212,7 +212,7 @@ int run_interactive(char *cmd, char *fmt, ...)
 	return status;
 }
 
-pid_t run_getty(char *tty, char *speed, char *term, int console)
+pid_t run_getty(char *tty, char *speed, char *term, int noclear, int console)
 {
 	pid_t pid;
 
@@ -230,7 +230,7 @@ pid_t run_getty(char *tty, char *speed, char *term, int console)
 		else
 			prctl(PR_SET_NAME, "finit-getty", 0, 0, 0);
 
-		_exit(getty(tty, speed, term, NULL));
+		_exit(getty(tty, speed, term, noclear, NULL));
 	}
 
 	return pid;

src/getty.c

@@ -63,7 +63,7 @@ static int readch(char *tty)
 	return ch1 & 0xFF;
 }
 
-static void stty(int fd, speed_t speed)
+static void stty(int fd, speed_t speed, int noclear)
 {
 	struct termios term;
 
@@ -98,9 +98,8 @@ static void stty(int fd, speed_t speed)
 	term.c_cc[VERASE] = CERASE;
 	tcsetattr(fd, TCSANOW, &term);
 
-	/* Clear screen in silent mode */
-	if (log_is_silent())
-		print("\033[r\033[H\033[J");
+	if (!noclear)
+		print("\e[r\e[H\e[J");
 }
 
 /*
@@ -291,7 +290,7 @@ static speed_t do_parse_speed(char *baud)
 	return B0;
 }
 
-int getty(char *tty, char *baud, char *term, char *user)
+int getty(char *tty, char *baud, char *term, int noclear, char *user)
 {
 	int fd;
 	char name[30];
@@ -328,7 +327,7 @@ int getty(char *tty, char *baud, char *term, char *user)
 	sa.sa_handler = _exit;
 	sigaction(SIGQUIT, &sa, NULL);
 
-	stty(fd, speed);
+	stty(fd, speed, noclear);
 	close(fd);
 	utmp_set_login(tty, NULL);
 

src/helpers.h

@@ -63,7 +63,7 @@ void    set_hostname    (char **hostname);
 int     complete        (char *cmd, int pid);
 int     run             (char *cmd);
 int     run_interactive (char *cmd, char *fmt, ...);
-pid_t   run_getty       (char *tty, char *speed, char *term, int console);
+pid_t   run_getty       (char *tty, char *speed, char *term, int noclear, int console);
 int     run_parts       (char *dir, char *cmd);
 
 static inline void create(char *path, mode_t mode, uid_t uid, gid_t gid)

src/tty.c

@@ -44,11 +44,11 @@ static pid_t fallback = 0;
 static LIST_HEAD(, tty_node) tty_list = LIST_HEAD_INITIALIZER();
 
 
-/* tty [!1-9,S] <DEV> [BAUD[,BAUD,...]] [TERM] */
+/* tty [!1-9,S] <DEV> [BAUD[,BAUD,...]] [TERM] [noclear] */
 int tty_register(char *line)
 {
 	tty_node_t *entry;
-	int         insert = 0;
+	int         insert = 0, noclear = 0;
 	char       *tok, *dev = NULL, *baud = NULL;
 	char       *runlevels = NULL, *term = NULL;
 
@@ -65,6 +65,8 @@ int tty_register(char *line)
 			dev = tok;
 		else if (isdigit(tok[0]))
 			baud = tok;
+		else if (!strcmp(tok, "noclear"))
+			noclear = 1;
 		else
 			term = tok;
 
@@ -87,6 +89,7 @@ int tty_register(char *line)
 	entry->data.name = strdup(dev);
 	entry->data.baud = baud ? strdup(baud) : NULL;
 	entry->data.term = term ? strdup(term) : NULL;
+	entry->data.noclear = noclear;
 	entry->data.runlevels = conf_parse_runlevels(runlevels);
 	_d("Registering tty %s at %s baud with term=%s on runlevels %s",
 	   dev, baud ?: "NULL", term ?: "N/A", runlevels ?: "[2-5]");
@@ -212,7 +215,7 @@ void tty_start(finit_tty_t *tty)
 		return;
 	}
 
-	tty->pid = run_getty(dev, tty->baud, tty->term, is_console);
+	tty->pid = run_getty(dev, tty->baud, tty->term, tty->noclear, is_console);
 }
 
 void tty_stop(finit_tty_t *tty)

src/tty.h

@@ -34,6 +34,7 @@ typedef struct {
 	char  *name;
 	char  *baud;
 	char  *term;
+	int    noclear;
 	int    runlevels;
 
 	int    pid;