diff -up util-linux-2.23.2/term-utils/agetty.c.kzak util-linux-2.23.2/term-utils/agetty.c

--- util-linux-2.23.2/term-utils/agetty.c.kzak	2013-07-30 11:14:18.124912322 +0200

+++ util-linux-2.23.2/term-utils/agetty.c	2013-09-09 09:07:46.406689270 +0200

@@ -132,13 +132,20 @@ struct options {

 	int delay;			/* Sleep seconds before prompt */

 	int nice;			/* Run login with this priority */

 	int numspeed;			/* number of baud rates to try */

+	int clocal;			/* CLOCAL_MODE_* */

 	speed_t speeds[MAX_SPEED];	/* baud rates to be tried */

 };

+enum {

+	CLOCAL_MODE_AUTO = 0,

+	CLOCAL_MODE_ALWAYS,

+	CLOCAL_MODE_NEVER

+};

+

 #define	F_PARSE		(1<<0)	/* process modem status messages */

 #define	F_ISSUE		(1<<1)	/* display /etc/issue */

 #define	F_RTSCTS	(1<<2)	/* enable RTS/CTS flow control */

-#define F_LOCAL		(1<<3)	/* force local */

+

 #define F_INITSTRING    (1<<4)	/* initstring is set */

 #define F_WAITCRLF	(1<<5)	/* wait for CR or LF */

 #define F_CUSTISSUE	(1<<6)	/* give alternative issue file */

@@ -235,10 +242,13 @@ static void login_options_to_argv(char *

 static char *fakehost;

 #ifdef DEBUGGING

-#define debug(s) do { fprintf(dbf,s); fflush(dbf); } while (0)

+# ifndef DEBUG_OUTPUT

+#  define DEBUG_OUTPUT "/dev/ttyp0"

+# endif

+# define debug(s) do { fprintf(dbf,s); fflush(dbf); } while (0)

 FILE *dbf;

 #else

-#define debug(s) do { ; } while (0)

+# define debug(s) do { ; } while (0)

 #endif

 int main(int argc, char **argv)

@@ -270,7 +280,7 @@ int main(int argc, char **argv)

 	sigaction(SIGINT, &sa, &sa_int);

 #ifdef DEBUGGING

-	dbf = fopen("/dev/ttyp0", "w");

+	dbf = fopen(DEBUG_OUTPUT, "w");

 	for (int i = 1; i < argc; i++)

 		debug(argv[i]);

 #endif				/* DEBUGGING */

@@ -311,8 +321,10 @@ int main(int argc, char **argv)

 			   strlen(options.initstring));

 	}

-	if (!serial_tty_option(&options, F_LOCAL))

-		/* Go to blocking write mode unless -L is specified. */

+	if (options.flags & F_VCONSOLE || options.clocal != CLOCAL_MODE_ALWAYS)

+		/* Go to blocking mode unless -L is specified, this change

+		 * affects stdout, stdin and stderr as all the file descriptors

+		 * are created by dup().   */

 		fcntl(STDOUT_FILENO, F_SETFL,

 		      fcntl(STDOUT_FILENO, F_GETFL, 0) & ~O_NONBLOCK);

@@ -420,6 +432,12 @@ int main(int argc, char **argv)

 				options.tty);

 	}

+#ifdef DEBUGGING

+	fprintf(dbf, "read %c\n", ch);

+	if (close_stream(dbf) != 0)

+		log_err("write failed: %s", DEBUG_OUTPUT);

+#endif

+

 	/* Let the login program take care of password validation. */

 	execv(options.login, login_argv);

 	log_err(_("%s: can't exec %s: %m"), options.tty, login_argv[0]);

@@ -534,7 +552,7 @@ static void parse_args(int argc, char **

 		{  "init-string",    required_argument,  0,  'I'  },

 		{  "noclear",	     no_argument,	 0,  'J'  },

 		{  "login-program",  required_argument,  0,  'l'  },

-		{  "local-line",     no_argument,	 0,  'L'  },

+		{  "local-line",     optional_argument,	 0,  'L'  },

 		{  "extract-baud",   no_argument,	 0,  'm'  },

 		{  "skip-login",     no_argument,	 0,  'n'  },

 		{  "nonewline",	     no_argument,	 0,  'N'  },

@@ -603,7 +621,18 @@ static void parse_args(int argc, char **

 			op->login = optarg;

 			break;

 		case 'L':

-			op->flags |= F_LOCAL;

+			/* -L and -L=always have the same meaning */

+			op->clocal = CLOCAL_MODE_ALWAYS;

+			if (optarg) {

+				if (strcmp(optarg, "=always") == 0)

+					op->clocal = CLOCAL_MODE_ALWAYS;

+				else if (strcmp(optarg, "=never") == 0)

+					op->clocal = CLOCAL_MODE_NEVER;

+				else if (strcmp(optarg, "=auto") == 0)

+					op->clocal = CLOCAL_MODE_AUTO;

+				else

+					log_err(_("unssuported --local-line mode argument"));

+			}

 			break;

 		case 'm':

 			op->flags |= F_PARSE;

@@ -1090,8 +1119,19 @@ static void termio_init(struct options *

 	cfsetispeed(tp, ispeed);

 	cfsetospeed(tp, ospeed);

-	if (op->flags & F_LOCAL)

-		tp->c_cflag |= CLOCAL;

+	/* The default is to follow setting from kernel, but it's possible

+	 * to explicitly remove/add CLOCAL flag by -L[=<mode>]*/

+	switch (op->clocal) {

+	case CLOCAL_MODE_ALWAYS:

+		tp->c_cflag |= CLOCAL;		/* -L or -L=always */

+		break;

+	case CLOCAL_MODE_NEVER:

+		tp->c_cflag &= ~CLOCAL;		/* -L=never */

+		break;

+	case CLOCAL_MODE_AUTO:			/* -L=auto */

+		break;

+	}

+

 #ifdef HAVE_STRUCT_TERMIOS_C_LINE

 	tp->c_line = 0;

 #endif

@@ -1412,9 +1452,10 @@ static char *get_logname(struct options

 			if (read(STDIN_FILENO, &c, 1) < 1) {

-				/* Do not report trivial like EINTR/EIO errors. */

+				/* The terminal could be open with O_NONBLOCK when

+				 * -L (force CLOCAL) is specified...  */

 				if (errno == EINTR || errno == EAGAIN) {

-					usleep(1000);

+					usleep(250000);

 					continue;

 				}

 				switch (errno) {

@@ -1648,7 +1689,7 @@ static void __attribute__ ((__noreturn__

 	fputs(_(" -i, --noissue              do not display issue file\n"), out);

 	fputs(_(" -I, --init-string <string> set init string\n"), out);

 	fputs(_(" -l, --login-program <file> specify login program\n"), out);

-	fputs(_(" -L, --local-line           force local line\n"), out);

+	fputs(_(" -L, --local-line[=<mode>]  cotrol local line flag\n"), out);

 	fputs(_(" -m, --extract-baud         extract baud rate during connect\n"), out);

 	fputs(_(" -n, --skip-login           do not prompt for login\n"), out);

 	fputs(_(" -o, --login-options <opts> options that are passed to login\n"), out);