X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=networking%2Fslattach.c;h=e0a388926bdf5c6ca6293ab4101e79ba63062494;hb=bcdec1a8b8bf9fb3ea4de96d153b203e12e035fd;hp=3495df5988da15ada3ee6ed144da38d7e2daab43;hpb=833358798afe256352b4ba62a3d93e5273ce6533;p=oweals%2Fbusybox.git

diff --git a/networking/slattach.c b/networking/slattach.c
index 3495df598..e0a388926 100644
--- a/networking/slattach.c
+++ b/networking/slattach.c
@@ -4,7 +4,7 @@
  *
  * Author: Ignacio Garcia Perez (iggarpe at gmail dot com)
  *
- * License: GPLv2 or later, see LICENSE file in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  * There are some differences from the standard net-tools slattach:
  *
@@ -12,136 +12,107 @@
  *
  * - The -F options allows disabling of RTS/CTS flow control.
  */
+//config:config SLATTACH
+//config:	bool "slattach (6.1 kb)"
+//config:	default y
+//config:	select PLATFORM_LINUX
+//config:	help
+//config:	slattach configures serial line as SLIP network interface.
+
+//applet:IF_SLATTACH(APPLET(slattach, BB_DIR_SBIN, BB_SUID_DROP))
+/* shouldn't be NOEXEC: may sleep indefinitely */
+
+//kbuild:lib-$(CONFIG_SLATTACH) += slattach.o
+
+//usage:#define slattach_trivial_usage
+//usage:       "[-ehmLF] [-c SCRIPT] [-s BAUD] [-p PROTOCOL] SERIAL_DEVICE"
+//usage:#define slattach_full_usage "\n\n"
+//usage:       "Configure serial line as SLIP network interface\n"
+//usage:     "\n	-p PROT	Protocol: slip, cslip (default), slip6, clisp6, adaptive"
+//usage:     "\n	-s BAUD	Line speed"
+//usage:     "\n	-e	Exit after initialization"
+//usage:     "\n	-h	Exit if carrier is lost (else never exits)"
+//usage:     "\n	-c PROG	Run PROG on carrier loss"
+//usage:     "\n	-m	Do NOT set raw 8bit mode"
+//usage:     "\n	-L	Enable 3-wire operation"
+//usage:     "\n	-F	Disable RTS/CTS flow control"
 
 #include "libbb.h"
-#include "libiproute/utils.h" /* invarg() */
-
-/* Line discipline code table */
-static const char *const proto_names[] = {
-	"cslip"+1,	/* 0 */
-	"cslip",	/* 1 */
-	"cslip6"+1,	/* 2 */
-	"cslip6",	/* 3 */
-	"adaptive",	/* 8 */
-	NULL
-};
+#include "common_bufsiz.h"
+#include "libiproute/utils.h" /* invarg_1_to_2() */
 
 struct globals {
-	int handle;
 	int saved_disc;
 	struct termios saved_state;
-};
-#define G (*(struct globals*)&bb_common_bufsiz1)
-#define handle       (G.handle      )
-#define saved_disc   (G.saved_disc  )
-#define saved_state  (G.saved_state )
-#define INIT_G() do {} while (0)
+} FIX_ALIASING;
+#define G (*(struct globals*)bb_common_bufsiz1)
+#define INIT_G() do { setup_common_bufsiz(); } while (0)
 
+#define serial_fd 3
 
-/*
- * Save tty state and line discipline
- *
- * It is fine here to bail out on errors, since we haven modified anything yet
- */
-static void save_state(void)
-{
-	/* Save line status */
-	if (tcgetattr(handle, &saved_state) < 0)
-		bb_perror_msg_and_die("get state");
-
-	/* Save line discipline */
-	if (ioctl(handle, TIOCGETD, &saved_disc) < 0)
-		bb_perror_msg_and_die("get discipline");
-}
-
-static int set_termios_state_and_warn(struct termios *state)
+static int tcsetattr_serial_or_warn(struct termios *state)
 {
 	int ret;
 
-	ret = tcsetattr(handle, TCSANOW, state);
-	if (ret < 0) {
-		bb_perror_msg("set state");
+	ret = tcsetattr(serial_fd, TCSANOW, state);
+	if (ret != 0) {
+		bb_perror_msg("tcsetattr");
 		return 1; /* used as exitcode */
 	}
-	return 0;
+	return ret; /* 0 */
 }
 
-/*
- * Restore state and line discipline for ALL managed ttys
- *
- * Restoring ALL managed ttys is the only way to have a single
- * hangup delay.
- *
- * Go on after errors: we want to restore as many controlled ttys
- * as possible.
- */
-static void restore_state_and_exit(int exitcode) ATTRIBUTE_NORETURN;
+static void restore_state_and_exit(int exitcode) NORETURN;
 static void restore_state_and_exit(int exitcode)
 {
 	struct termios state;
 
 	/* Restore line discipline */
-	if (ioctl(handle, TIOCSETD, &saved_disc) < 0) {
-		bb_perror_msg("set discipline");
+	if (ioctl_or_warn(serial_fd, TIOCSETD, &G.saved_disc)) {
 		exitcode = 1;
 	}
 
 	/* Hangup */
-	memcpy(&state, &saved_state, sizeof(state));
+	memcpy(&state, &G.saved_state, sizeof(state));
 	cfsetispeed(&state, B0);
 	cfsetospeed(&state, B0);
-	if (set_termios_state_and_warn(&state))
-		exitcode = 1;
+	exitcode |= tcsetattr_serial_or_warn(&state);
 	sleep(1);
 
 	/* Restore line status */
-	if (set_termios_state_and_warn(&saved_state))
+	if (tcsetattr_serial_or_warn(&G.saved_state))
 		exit(EXIT_FAILURE);
+
 	if (ENABLE_FEATURE_CLEAN_UP)
-		close(handle);
+		close(serial_fd);
 
 	exit(exitcode);
 }
 
-/*
- * Set tty state, line discipline and encapsulation
- */
-static void set_state(struct termios *state, int encap)
-{
-	int disc;
-
-	/* Set line status */
-	if (set_termios_state_and_warn(state))
-		goto bad;
-	/* Set line discliple (N_SLIP always) */
-	disc = N_SLIP;
-	if (ioctl(handle, TIOCSETD, &disc) < 0) {
-		bb_perror_msg("set discipline");
-		goto bad;
-	}
-
-	/* Set encapsulation (SLIP, CSLIP, etc) */
-	if (ioctl(handle, SIOCSIFENCAP, &encap) < 0) {
-		bb_perror_msg("set encapsulation");
- bad:
-		restore_state_and_exit(1);
-	}
-}
-
-static void sig_handler(int signo)
+static void sig_handler(int signo UNUSED_PARAM)
 {
-	restore_state_and_exit(0);
+	restore_state_and_exit(EXIT_SUCCESS);
 }
 
-int slattach_main(int argc, char **argv);
-int slattach_main(int argc, char **argv)
+int slattach_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int slattach_main(int argc UNUSED_PARAM, char **argv)
 {
-	int i, encap, opt;
+	/* Line discipline code table */
+	static const char proto_names[] ALIGN1 =
+		"slip\0"        /* 0 */
+		"cslip\0"       /* 1 */
+		"slip6\0"       /* 2 */
+		"cslip6\0"      /* 3 */
+		"adaptive\0"    /* 8 */
+		;
+	static const int int_N_SLIP = N_SLIP;
+
+	int encap, opt, fd;
 	struct termios state;
 	const char *proto = "cslip";
-	const char *extcmd;				/* Command to execute after hangup */
+	const char *extcmd;   /* Command to execute after hangup */
 	const char *baud_str;
-	int baud_code = -1;				/* Line baud rate (system code) */
+	int baud_code = baud_code; /* for compiler */
 
 	enum {
 		OPT_p_proto  = 1 << 0,
@@ -157,17 +128,15 @@ int slattach_main(int argc, char **argv)
 	INIT_G();
 
 	/* Parse command line options */
-	opt = getopt32(argc, argv, "p:s:c:ehmLF", &proto, &baud_str, &extcmd);
+	opt = getopt32(argv, "^" "p:s:c:ehmLF" "\0" "=1",
+				&proto, &baud_str, &extcmd
+	);
 	/*argc -= optind;*/
 	argv += optind;
 
-	if (!*argv)
-		bb_show_usage();
-
-	encap = index_in_str_array(proto_names, proto);
-
+	encap = index_in_strings(proto_names, proto);
 	if (encap < 0)
-		invarg(proto, "protocol");
+		invarg_1_to_2(proto, "protocol");
 	if (encap > 3)
 		encap = 8;
 
@@ -175,52 +144,66 @@ int slattach_main(int argc, char **argv)
 	if (opt & OPT_s_baud) {
 		baud_code = tty_value_to_baud(xatoi(baud_str));
 		if (baud_code < 0)
-			invarg(baud_str, "baud rate");
-	}
-
-	/* Trap signals in order to restore tty states upon exit */
-	if (!(opt & OPT_e_quit)) {
-		signal(SIGHUP, sig_handler);
-		signal(SIGINT, sig_handler);
-		signal(SIGQUIT, sig_handler);
-		signal(SIGTERM, sig_handler);
+			invarg_1_to_2(baud_str, "baud rate");
 	}
 
 	/* Open tty */
-	handle = open(*argv, O_RDWR | O_NDELAY);
-	if (handle < 0) {
+	fd = open(*argv, O_RDWR | O_NDELAY);
+	if (fd < 0) {
 		char *buf = concat_path_file("/dev", *argv);
-		handle = xopen(buf, O_RDWR | O_NDELAY);
+		fd = xopen(buf, O_RDWR | O_NDELAY);
 		/* maybe if (ENABLE_FEATURE_CLEAN_UP) ?? */
 		free(buf);
 	}
+	xmove_fd(fd, serial_fd);
 
 	/* Save current tty state */
-	save_state();
+	if (tcgetattr(serial_fd, &G.saved_state) != 0)
+		bb_perror_msg_and_die("tcgetattr");
+	/* Save line discipline */
+	xioctl(serial_fd, TIOCGETD, &G.saved_disc);
+
+	/* Trap signals in order to restore tty states upon exit */
+	if (!(opt & OPT_e_quit)) {
+		bb_signals(0
+			+ (1 << SIGHUP)
+			+ (1 << SIGINT)
+			+ (1 << SIGQUIT)
+			+ (1 << SIGTERM)
+			, sig_handler);
+	}
 
 	/* Configure tty */
-	memcpy(&state, &saved_state, sizeof(state));
+	memcpy(&state, &G.saved_state, sizeof(state));
 	if (!(opt & OPT_m_nonraw)) { /* raw not suppressed */
 		memset(&state.c_cc, 0, sizeof(state.c_cc));
 		state.c_cc[VMIN] = 1;
 		state.c_iflag = IGNBRK | IGNPAR;
-		state.c_oflag = 0;
-		state.c_lflag = 0;
+		/*state.c_oflag = 0;*/
+		/*state.c_lflag = 0;*/
 		state.c_cflag = CS8 | HUPCL | CREAD
 		              | ((opt & OPT_L_local) ? CLOCAL : 0)
 		              | ((opt & OPT_F_noflow) ? 0 : CRTSCTS);
+		cfsetispeed(&state, cfgetispeed(&G.saved_state));
+		cfsetospeed(&state, cfgetospeed(&G.saved_state));
 	}
-
 	if (opt & OPT_s_baud) {
 		cfsetispeed(&state, baud_code);
 		cfsetospeed(&state, baud_code);
 	}
-
-	set_state(&state, encap);
+	/* Set line status */
+	if (tcsetattr_serial_or_warn(&state))
+		goto bad;
+	/* Set line disclipline (N_SLIP always) */
+	if (ioctl_or_warn(serial_fd, TIOCSETD, (void*)&int_N_SLIP))
+		goto bad;
+	/* Set encapsulation (SLIP, CSLIP, etc) */
+	if (ioctl_or_warn(serial_fd, SIOCSIFENCAP, &encap))
+		goto bad;
 
 	/* Exit now if option -e was passed */
 	if (opt & OPT_e_quit)
-		return 0;
+		return EXIT_SUCCESS;
 
 	/* If we're not requested to watch, just keep descriptor open
 	 * until we are killed */
@@ -230,17 +213,20 @@ int slattach_main(int argc, char **argv)
 
 	/* Watch line for hangup */
 	while (1) {
-		if (ioctl(handle, TIOCMGET, &i) < 0 || !(i & TIOCM_CAR))
-			goto no_carrier;
+		int modem_stat;
+		if (ioctl(serial_fd, TIOCMGET, &modem_stat))
+			break;
+		if (!(modem_stat & TIOCM_CAR))
+			break;
 		sleep(15);
 	}
 
- no_carrier:
-
 	/* Execute command on hangup */
 	if (opt & OPT_c_extcmd)
 		system(extcmd);
 
 	/* Restore states and exit */
-	restore_state_and_exit(0);
+	restore_state_and_exit(EXIT_SUCCESS);
+ bad:
+	restore_state_and_exit(EXIT_FAILURE);
 }