#include "libbb.h"
#include <syslog.h>
-#if ENABLE_FEATURE_UTMP
-# include <utmp.h> /* LOGIN_PROCESS */
-#endif
#ifndef IUCLC
# define IUCLC 0
#endif
/* Some shorthands for control characters */
#define CTL(x) ((x) ^ 0100) /* Assumes ASCII dialect */
-#define CR CTL('M') /* carriage return */
-#define NL CTL('J') /* line feed */
#define BS CTL('H') /* back space */
#define DEL CTL('?') /* delete */
/* Defaults for line-editing etc. characters; you may want to change this */
-#define DEF_ERASE DEL /* default erase character */
#define DEF_INTR CTL('C') /* default interrupt character */
#define DEF_QUIT CTL('\\') /* default quit char */
#define DEF_KILL CTL('U') /* default kill char */
#define DEF_EOF CTL('D') /* default EOF char */
#define DEF_EOL '\n'
-#define DEF_SWITCH 0 /* default switch char */
+#define DEF_SWITCH 0 /* default switch char (none) */
/*
* When multiple baud rates are specified on the command line,
//usage:#define getty_full_usage "\n\n"
//usage: "Open a tty, prompt for a login name, then invoke /bin/login\n"
//usage: "\nOptions:"
-//usage: "\n -h Enable hardware (RTS/CTS) flow control"
-//usage: "\n -i Don't display /etc/issue"
-//usage: "\n -L Local line, set CLOCAL on it"
+//usage: "\n -h Enable hardware RTS/CTS flow control"
+//usage: "\n -L Set CLOCAL (ignore Carrier Detect state)"
//usage: "\n -m Get baud rate from modem's CONNECT status message"
+//usage: "\n -n Don't prompt for login name"
//usage: "\n -w Wait for CR or LF before sending /etc/issue"
-//usage: "\n -n Don't prompt for a login name"
+//usage: "\n -i Don't display /etc/issue"
//usage: "\n -f ISSUE_FILE Display ISSUE_FILE instead of /etc/issue"
//usage: "\n -l LOGIN Invoke LOGIN instead of /bin/login"
-//usage: "\n -t SEC Terminate after SEC if no username is read"
+//usage: "\n -t SEC Terminate after SEC if no login name is read"
//usage: "\n -I INITSTR Send INITSTR before anything else"
//usage: "\n -H HOST Log HOST into the utmp file as the hostname"
//usage: "\n"
}
}
+static void set_termios(void)
+{
+ if (tcsetattr_stdin_TCSANOW(&G.termios) < 0)
+ bb_perror_msg_and_die("tcsetattr");
+}
+
/* We manipulate termios this way:
* - first, we read existing termios settings
* - termios_init modifies some parts and sets it
*/
static void termios_init(int speed)
{
- /* Flush input and output queues, important for modems!
- * Users report losing previously queued output chars, and I hesitate
- * to use tcdrain here instead of tcflush - I imagine it can block.
- * Using small sleep instead.
+ /* Try to drain output buffer, with 5 sec timeout.
+ * Added on request from users of ~600 baud serial interface
+ * with biggish buffer on a 90MHz CPU.
+ * They were losing hundreds of bytes of buffered output
+ * on tcflush.
*/
- usleep(100*1000); /* 0.1 sec */
+ signal_no_SA_RESTART_empty_mask(SIGALRM, record_signo);
+ alarm(5);
+ tcdrain(STDIN_FILENO);
+ alarm(0);
+ signal(SIGALRM, SIG_DFL); /* do not break -t TIMEOUT! */
+
+ /* Flush input and output queues, important for modems! */
tcflush(STDIN_FILENO, TCIOFLUSH);
/* Set speed if it wasn't specified as "0" on command line */
if (speed != B0)
cfsetspeed(&G.termios, speed);
- /*
- * Initial termios settings: 8-bit characters, raw-mode, blocking i/o.
+ /* Initial termios settings: 8-bit characters, raw mode, blocking i/o.
* Special characters are set after we have read the login name; all
- * reads will be done in raw mode anyway. Errors will be dealt with
- * later on.
+ * reads will be done in raw mode anyway.
*/
- G.termios.c_cflag = CS8 | HUPCL | CREAD;
- if (option_mask32 & F_LOCAL)
+ /* Clear all bits except: */
+ G.termios.c_cflag &= (0
+ /* 2 stop bits (1 otherwise)
+ * Enable parity bit (both on input and output)
+ * Odd parity (else even)
+ */
+ | CSTOPB | PARENB | PARODD
+#ifdef CMSPAR
+ | CMSPAR /* mark or space parity */
+#endif
+ | CBAUD /* (output) baud rate */
+#ifdef CBAUDEX
+ | CBAUDEX /* (output) baud rate */
+#endif
+#ifdef CIBAUD
+ | CIBAUD /* input baud rate */
+#endif
+ );
+ /* Set: 8 bits; hang up (drop DTR) on last close; enable receive */
+ G.termios.c_cflag |= CS8 | HUPCL | CREAD;
+ if (option_mask32 & F_LOCAL) {
+ /* ignore Carrier Detect pin:
+ * opens don't block when CD is low,
+ * losing CD doesn't hang up processes whose ctty is this tty
+ */
G.termios.c_cflag |= CLOCAL;
+ }
+#ifdef CRTSCTS
+ if (option_mask32 & F_RTSCTS)
+ G.termios.c_cflag |= CRTSCTS; /* flow control using RTS/CTS pins */
+#endif
G.termios.c_iflag = 0;
G.termios.c_lflag = 0;
+ /* non-raw output; add CR to each NL */
G.termios.c_oflag = OPOST | ONLCR;
- G.termios.c_cc[VMIN] = 1;
- G.termios.c_cc[VTIME] = 0;
+
+ G.termios.c_cc[VMIN] = 1; /* block reads if < 1 char is available */
+ G.termios.c_cc[VTIME] = 0; /* no timeout (reads block forever) */
#ifdef __linux__
G.termios.c_line = 0;
#endif
-#ifdef CRTSCTS
- if (option_mask32 & F_RTSCTS)
- G.termios.c_cflag |= CRTSCTS;
-#endif
- tcsetattr_stdin_TCSANOW(&G.termios);
+ set_termios();
debug("term_io 2\n");
}
static void termios_final(void)
{
- /* General terminal-independent stuff */
- G.termios.c_iflag |= IXON | IXOFF; /* 2-way flow control */
+ /* software flow control on output (stop sending if XOFF is recvd);
+ * and on input (send XOFF when buffer is full)
+ */
+ G.termios.c_iflag |= IXON | IXOFF;
+ if (G.eol == '\r') {
+ G.termios.c_iflag |= ICRNL; /* map CR on input to NL */
+ }
+ /* Other bits in c_iflag:
+ * IXANY Any recvd char enables output (any char is also a XON)
+ * INPCK Enable parity check
+ * IGNPAR Ignore parity errors (drop bad bytes)
+ * PARMRK Mark parity errors with 0xff, 0x00 prefix
+ * (else bad byte is received as 0x00)
+ * ISTRIP Strip parity bit
+ * IGNBRK Ignore break condition
+ * BRKINT Send SIGINT on break - maybe set this?
+ * INLCR Map NL to CR
+ * IGNCR Ignore CR
+ * ICRNL Map CR to NL
+ * IUCLC Map uppercase to lowercase
+ * IMAXBEL Echo BEL on input line too long
+ * IUTF8 Appears to affect tty's idea of char widths,
+ * observed to improve backspacing through Unicode chars
+ */
+
+ /* line buffered input (NL or EOL or EOF chars end a line);
+ * recognize INT/QUIT/SUSP chars;
+ * echo input chars;
+ * echo BS-SP-BS on erase character;
+ * echo kill char specially, not as ^c (ECHOKE controls how exactly);
+ * erase all input via BS-SP-BS on kill char (else go to next line)
+ */
G.termios.c_lflag |= ICANON | ISIG | ECHO | ECHOE | ECHOK | ECHOKE;
- /* no longer in lflag: | ECHOCTL | ECHOPRT */
- G.termios.c_oflag |= OPOST;
- /* G.termios.c_cflag = 0; */
+ /* Other bits in c_lflag:
+ * XCASE Map uppercase to \lowercase [tried, doesn't work]
+ * ECHONL Echo NL even if ECHO is not set
+ * ECHOCTL Echo ctrl chars as ^c (else don't echo) - maybe set this?
+ * ECHOPRT On erase, echo erased chars
+ * [qwe<BS><BS><BS> input looks like "qwe\ewq/" on screen]
+ * NOFLSH Don't flush input buffer after interrupt or quit chars
+ * IEXTEN Enable extended functions (??)
+ * [glibc says it enables c_cc[LNEXT] "enter literal char"
+ * and c_cc[VDISCARD] "toggle discard buffered output" chars]
+ * FLUSHO Output being flushed (c_cc[VDISCARD] is in effect)
+ * PENDIN Retype pending input at next read or input char
+ * (c_cc[VREPRINT] is being processed)
+ * TOSTOP Send SIGTTOU for background output
+ * (why "stty sane" unsets this bit?)
+ */
+
G.termios.c_cc[VINTR] = DEF_INTR;
G.termios.c_cc[VQUIT] = DEF_QUIT;
G.termios.c_cc[VEOF] = DEF_EOF;
#ifdef VSWTC
G.termios.c_cc[VSWTC] = DEF_SWITCH;
#endif
-
- /* Account for special characters seen in input */
- if (G.eol == CR) {
- G.termios.c_iflag |= ICRNL; /* map CR in input to NL */
- /* already done by termios_init */
- /* G.termios.c_oflag |= ONLCR; map NL in output to CR-NL */
- }
- G.termios.c_cc[VKILL] = DEF_KILL;
-
-#ifdef CRTSCTS
- /* Optionally enable hardware flow control */
- if (option_mask32 & F_RTSCTS)
- G.termios.c_cflag |= CRTSCTS;
+#ifdef VSWTCH
+ G.termios.c_cc[VSWTCH] = DEF_SWITCH;
#endif
+ G.termios.c_cc[VKILL] = DEF_KILL;
+ /* Other control chars:
+ * VEOL2
+ * VERASE, VWERASE - (word) erase. we may set VERASE in get_logname
+ * VREPRINT - reprint current input buffer
+ * VLNEXT, VDISCARD, VSTATUS
+ * VSUSP, VDSUSP - send (delayed) SIGTSTP
+ * VSTART, VSTOP - chars used for IXON/IXOFF
+ */
- /* Finally, make the new settings effective */
- if (tcsetattr_stdin_TCSANOW(&G.termios) < 0)
- bb_perror_msg_and_die("tcsetattr");
+ set_termios();
}
/* extract baud rate from modem status message */
* modem status messages is enabled.
*/
- /*
- * Don't block if input queue is empty.
- * Errors will be dealt with later on.
- */
- G.termios.c_cc[VMIN] = 0; /* don't block if queue empty */
- tcsetattr_stdin_TCSANOW(&G.termios);
+ G.termios.c_cc[VMIN] = 0; /* don't block reads (min read is 0 chars) */
+ set_termios();
/*
* Wait for a while, then read everything the modem has said so far and
}
}
- /* Restore terminal settings. Errors will be dealt with later on */
+ /* Restore terminal settings */
G.termios.c_cc[VMIN] = 1; /* restore to value set by termios_init */
- tcsetattr_stdin_TCSANOW(&G.termios);
+ set_termios();
}
/* get user name, establish parity, speed, erase, kill, eol;
/* Flush pending input (esp. after parsing or switching the baud rate) */
usleep(100*1000); /* 0.1 sec */
- tcflush(STDIN_FILENO, TCIOFLUSH);
+ tcflush(STDIN_FILENO, TCIFLUSH);
/* Prompt for and read a login name */
G.line_buf[0] = '\0';
/* Do erase, kill and end-of-line processing */
switch (c) {
- case CR:
- case NL:
+ case '\r':
+ case '\n':
*bp = '\0';
G.eol = c;
goto got_logname;
#ifdef ISSUE
G.issue = ISSUE; /* default issue file */
#endif
- G.eol = CR;
+ G.eol = '\r';
/* Parse command-line arguments */
parse_args(argv);
/* Set the optional timer */
alarm(G.timeout); /* if 0, alarm is not set */
+//BUG: death by signal won't restore termios
/* Optionally wait for CR or LF before writing /etc/issue */
if (option_mask32 & F_WAITCRLF) {
char ch;
-
debug("waiting for cr-lf\n");
while (safe_read(STDIN_FILENO, &ch, 1) == 1) {
debug("read %x\n", (unsigned char)ch);
/* We are here only if G.numspeed > 1 */
baud_index = (baud_index + 1) % G.numspeed;
cfsetspeed(&G.termios, G.speeds[baud_index]);
- tcsetattr_stdin_TCSANOW(&G.termios);
+ set_termios();
}
}
projects / platform / upstream / busybox.git / blobdiff