Add a helper that checks for serial and serial-like consoles

This works by doing checks from udev that emit upstart events. upstart
listens to these events and starts a getty if needed.

1 files changed, 154 insertions, 0 deletions

diff --git a/src/console_check.c b/src/console_check.c
new file mode 100644
index 00000000..243e9be5
--- /dev/null
+++ b/src/console_check.c
@@ -0,0 +1,154 @@
+
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+
+#include <linux/serial.h>
+
+struct speeds
+{
+	speed_t speed;
+	unsigned long value;
+};
+
+struct speeds speed_map[] =
+{
+	{B50, 50},
+	{B75, 75},
+	{B110, 110},
+        {B134, 134},
+        {B150, 150},
+        {B200, 200},
+        {B300, 300},
+        {B600, 600},
+        {B1200, 1200},
+        {B1800, 1800},
+        {B2400, 2400},
+        {B4800, 4800},
+        {B9600, 9600},
+        {B19200, 19200},
+        {B38400, 38400},
+#ifdef B57600
+	{B57600, 57600},
+#endif
+#ifdef B115200
+	{B115200, 115200},
+#endif
+#ifdef B230400
+  	{B230400, 230400},
+#endif
+#ifdef B460800
+	{B460800, 460800},
+#endif
+	{0, 0}
+};
+
+int termcmp(struct termios *a, struct termios *b) {
+	if (a->c_iflag != b->c_iflag || a->c_oflag != b->c_oflag ||
+	    a->c_cflag != b->c_cflag || a->c_lflag != b->c_lflag ||
+	    a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed)
+		return 1;
+	return memcmp(a->c_cc, b->c_cc, sizeof(a->c_cc));
+}       
+
+int get_serial_speed(int fd) {
+	struct termios mode;
+	
+	if (!tcgetattr(fd, &mode)) {
+		int i;
+		speed_t speed;
+		
+		speed = cfgetospeed(&mode);
+		for (i = 0; speed_map[i].value != 0; i++)
+			if (speed_map[i].speed == speed)
+				return speed_map[i].value;
+	}
+	return 0;
+}
+
+int compare_termios_to_console(char *dev, int *speed) {
+	struct termios cmode, mode;
+	int fd, cfd;
+
+	cfd = open ("/dev/console", O_RDONLY);
+	tcgetattr(cfd, &cmode);
+	close(cfd);
+
+	fd = open(dev, O_RDONLY);
+	tcgetattr(fd, &mode);
+
+	if (!termcmp(&cmode, &mode)) {
+		*speed = get_serial_speed(fd);
+		close(fd);
+		return 1;
+	}
+	close(fd);
+	return 0;
+}
+
+char *check_serial_console(int *speed) {
+	int fd;
+	char *ret = NULL, *device;
+	char twelve = 12;
+	struct serial_struct si, si2;
+
+	fd = open("/dev/console", O_RDWR);
+	if (ioctl (fd, TIOCLINUX, &twelve) >= 0)
+		goto out;
+
+	if (ioctl(fd, TIOCGSERIAL, &si) < 0)
+		goto out;
+	close(fd);
+
+	asprintf(&device, "ttyS%d", si.line);
+	fd = open(device, O_RDWR|O_NONBLOCK);
+	if (fd == -1)
+		goto out;
+
+	if (ioctl(fd, TIOCGSERIAL, &si2) < 0)
+		goto out;
+
+	if (memcmp(&si,&si2, sizeof(si)))
+		goto out;
+
+	*speed = get_serial_speed(fd);
+	ret = device;
+out:
+	close(fd);
+	return ret;
+}
+
+int emit_console_event(char *dev, int speed) {
+	char *args[] = { "initctl", "emit", "--no-wait", "fedora.serial-console-available", NULL, NULL, NULL };
+	
+	args[4] = dev;
+	if (speed)
+		asprintf(&args[5],"%d",speed);
+	execv("/sbin/initctl", args);
+	return 1;	
+}
+
+int main(int argc, char **argv) {
+	char *device;
+	int speed;
+	
+	if (argc < 2) {
+		printf("usage: console_check <device>\n");
+		exit(1);
+	}
+	chdir("/dev");
+	device = argv[1];
+	if (!strcmp(device, "console")) {
+		device = check_serial_console(&speed);
+		if (device)
+			return emit_console_event(device, speed);
+	} else if (compare_termios_to_console(device, &speed)) {
+		return emit_console_event(device, speed);
+	}
+	return 0;
+}