Merge commit 'da4441c44f6efccb6f7b7588404d9c6bfb7b6af8' into merge

Conflicts:
	libbb/vfork_daemon_rexec.c
	networking/wget.c
	procps/ps.c

2 files changed, 137 insertions, 54 deletions

diff --git a/loginutils/Config.src b/loginutils/Config.src
index 4c771bbc4..0d7f50cf1 100644
--- a/loginutils/Config.src
+++ b/loginutils/Config.src
@@ -181,7 +181,19 @@ config GETTY
         default y
         select FEATURE_SYSLOG
         help
-          getty lets you log in on a tty, it is normally invoked by init.
+          getty lets you log in on a tty. It is normally invoked by init.
+
+          Note that you can save a few bytes by disabling it and
+          using login applet directly.
+          If you need to reset tty attributes before calling login,
+          this script approximates getty:
+
+          exec </dev/$1 >/dev/$1 2>&1 || exit 1
+          reset
+          stty sane; stty ispeed 38400; stty ospeed 38400
+          printf "%s login: " "`hostname`"
+          read -r login
+          exec /bin/login "$login"
 
 config LOGIN
         bool "login"
diff --git a/loginutils/getty.c b/loginutils/getty.c
index b71d68a1f..3f20c8e81 100644
--- a/loginutils/getty.c
+++ b/loginutils/getty.c
@@ -106,15 +106,15 @@ struct globals {
 //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"
@@ -224,6 +224,12 @@ static void open_tty(void)
         }
 }
 
+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
@@ -233,53 +239,128 @@ static void open_tty(void)
  */
 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;
@@ -290,24 +371,17 @@ static void termios_final(void)
 #ifdef VSWTCH
         G.termios.c_cc[VSWTCH] = DEF_SWITCH;
 #endif
-
-        /* Account for special characters seen in input */
-        if (G.eol == '\r') {
-                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;
+        /* 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
+         */
 
-#ifdef CRTSCTS
-        /* Optionally enable hardware flow control */
-        if (option_mask32 & F_RTSCTS)
-                G.termios.c_cflag |= CRTSCTS;
-#endif
-
-        /* 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 */
@@ -330,12 +404,8 @@ static void auto_baud(void)
          * 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
@@ -357,9 +427,9 @@ static void auto_baud(void)
                 }
         }
 
-        /* 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;
@@ -538,6 +608,7 @@ int getty_main(int argc UNUSED_PARAM, char **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) {
@@ -565,7 +636,7 @@ int getty_main(int argc UNUSED_PARAM, char **argv)
                         /* 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();
                 }
         }