Add support for a fallback shell if no tty is setup

Try to do better by the user, by default, if no tty is specified in the
finit.conf.  This way the user will at least have a way to interact with
the system and repair it.

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

conf.c

@@ -243,11 +243,17 @@ static int parse_conf(char *file)
 
 int parse_finit_conf(char *file)
 {
+	int result;
+
 	username = strdup(DEFUSER);
 	hostname = strdup(DEFHOST);
 	rcsd     = strdup(FINIT_RCSD);
 
-	return parse_conf(file);
+	result = parse_conf(file);
+	if (!tty_num())
+		tty_register(FALLBACK_SHELL);
+
+	return result;
 }
 
 

finit.h

@@ -27,6 +27,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <paths.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.h>
@@ -35,7 +36,7 @@
 
 /* Distribution specific configuration */
 #if defined EMBEDDED_SYSTEM
-# define CONSOLE                "/dev/console"
+# define CONSOLE		_PATH_CONSOLE
 # define SETUP_DEVFS		"/sbin/mdev -s"
 # define GETTY			"/sbin/getty -L"
 # define GETTY_BUSYBOX
@@ -53,6 +54,10 @@
 # define HAVE_DBUS
 #endif
 
+#ifndef FALLBACK_SHELL
+# define FALLBACK_SHELL		_PATH_BSHELL
+#endif
+
 #ifndef DEFUSER
 # define DEFUSER		"root"
 #endif

tty.c

@@ -102,6 +102,17 @@ tty_node_t *tty_find(char *dev)
 	return NULL;
 }
 
+size_t tty_num(void)
+{
+	size_t num = 0;
+	tty_node_t *entry;
+
+	LIST_FOREACH(entry, &tty_list, link)
+		num++;
+
+	return num;
+}
+
 tty_node_t *tty_find_by_pid(pid_t pid)
 {
 	tty_node_t *entry;
@@ -127,13 +138,17 @@ void tty_start(finit_tty_t *tty)
 	if (console && !strcmp(tty->name, console))
 		is_console = 1;
 
+	if (!strcmp(tty->name, _PATH_DEV)) {
 #if   defined(GETTY_AGETTY)
 		snprintf(line, sizeof(line), "%s %s %d %s", GETTY, tty->name, tty->baud, tty->term ?: "");
 #elif defined(GETTY_BUSYBOX)
 		snprintf(line, sizeof(line), "%s %d %s %s", GETTY, tty->baud, tty->name, tty->term ?: "");
 #else
-#error No GETTY defined!
+		strlcpy(line, FALLBACK_CONSOLE, sizeof(line));
 #endif
+	} else {
+		strlcpy(line, tty->name, sizeof(line));
+	}
 	cmd = strtok(line, " ");
 	args[i++] = basename(cmd);
 	while ((arg = strtok(NULL, " ")))

tty.h

@@ -47,6 +47,7 @@ typedef struct tty_node {
 
 int	    tty_register    (char *line);
 tty_node_t *tty_find	    (char *dev);
+size_t	    tty_num	    (void);
 tty_node_t *tty_find_by_pid (pid_t pid);
 void	    tty_start	    (finit_tty_t *tty);
 void	    tty_stop	    (finit_tty_t *tty);