From 2b57b6cd43211e2430c78caa0895f41376f29dc1 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 22 Jan 2011 03:06:40 +0100 Subject: [PATCH] getty: comment out parity detection code; improve usage text function old new delta packed_usage 28155 28191 +36 static.erase 12 - -12 getty_main 1847 1621 -226 ------------------------------------------------------------------------------ (add/remove: 0/1 grow/shrink: 1/1 up/down: 36/-238) Total: -202 bytes Signed-off-by: Denys Vlasenko --- loginutils/getty.c | 112 +++++++++++++++++++++++++++++---------------- 1 file changed, 72 insertions(+), 40 deletions(-) diff --git a/loginutils/getty.c b/loginutils/getty.c index 0f5e333a7..94c9147ab 100644 --- a/loginutils/getty.c +++ b/loginutils/getty.c @@ -58,9 +58,16 @@ static FILE *dbf; * and for line editing at the same time. */ -/* I doubt there are systems which still need this */ +/* I doubt there are systems which still... */ +/* ...have only uppercase: */ #undef HANDLE_ALLCAPS +/* ...use # and @ for backspace and line erase: */ #undef ANCIENT_BS_KILL_CHARS +/* It actually makes sense (tries to guess parity by looking at 7th bit) + * but it's broken, and interferes with non-ASCII login names + * (yes, I did receive complains from real users): + */ +#undef BROKEN_PARITY_DETECTION_CODE #undef _PATH_LOGIN #define _PATH_LOGIN "/bin/login" @@ -108,8 +115,11 @@ struct options { /* Storage for things detected while the login name was read. */ struct chardata { unsigned char erase; /* erase character */ +#ifdef ANCIENT_BS_KILL_CHARS unsigned char kill; /* kill character */ +#endif unsigned char eol; /* end-of-line character */ +#ifdef BROKEN_PARITY_DETECTION_CODE unsigned char parity; /* what parity did we see */ /* (parity & 1): saw odd parity char with 7th bit set */ /* (parity & 2): saw even parity char with 7th bit set */ @@ -117,7 +127,8 @@ struct chardata { /* parity == 1: probably 7-bit, odd parity? */ /* parity == 2: probably 7-bit, even parity? */ /* parity == 3: definitely 8 bit, no parity! */ - /* Hmm... with any value of "parity" 8 bit, no parity is possible */ + /* Hmm... with any value of parity "8 bit, no parity" is possible */ +#endif #ifdef HANDLE_ALLCAPS unsigned char capslock; /* upper case without lower case */ #endif @@ -126,9 +137,13 @@ struct chardata { /* Initial values for the above. */ static const struct chardata init_chardata = { DEF_ERASE, /* default erase character */ +#ifdef ANCIENT_BS_KILL_CHARS DEF_KILL, /* default kill character */ +#endif 13, /* default eol char */ +#ifdef BROKEN_PARITY_DETECTION_CODE 0, /* space parity */ +#endif #ifdef HANDLE_ALLCAPS 0, /* no capslock */ #endif @@ -137,21 +152,23 @@ static const struct chardata init_chardata = { #define line_buf bb_common_bufsiz1 //usage:#define getty_trivial_usage -//usage: "[OPTIONS] BAUD_RATE TTY [TERMTYPE]" +//usage: "[OPTIONS] BAUD_RATE[,BAUD_RATE]... TTY [TERMTYPE]" //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, don't do carrier detect" +//usage: "\n -L Local line, set CLOCAL on it" //usage: "\n -m Get baud rate from modem's CONNECT status message" -//usage: "\n -w Wait for a CR or LF before sending /etc/issue" -//usage: "\n -n Don't prompt the user for a 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 -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 -I INITSTR Send INITSTR before anything else" //usage: "\n -H HOST Log HOST into the utmp file as the hostname" +//usage: "\n" +//usage: "\nBAUD_RATE of 0 leaves it unchanged" static const char opt_string[] ALIGN1 = "I:LH:f:hil:mt:wn"; #define F_INITSTRING (1 << 0) /* -I */ @@ -259,29 +276,27 @@ static void open_tty(const char *tty) /* termios_init - initialize termios settings */ static void termios_init(struct termios *tp, int speed) { - speed_t ispeed, ospeed; + /* Flush input and output queues, important for modems! */ + /* TODO: sleep(1)? Users report lost chars, and I hesitate + * to use tcdrain here instead of tcflush */ + tcflush(0, TCIOFLUSH); + + /* Set speed if it wasn't specified as "0" on command line. */ + if (speed != B0) { + cfsetispeed(tp, speed); + cfsetospeed(tp, speed); + } /* * 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. */ - /* flush input and output queues, important for modems! */ - tcflush(0, TCIOFLUSH); - ispeed = ospeed = speed; - if (speed == B0) { - /* Speed was specified as "0" on command line. - * Just leave it unchanged */ - ispeed = cfgetispeed(tp); - ospeed = cfgetospeed(tp); - } tp->c_cflag = CS8 | HUPCL | CREAD; if (option_mask32 & F_LOCAL) tp->c_cflag |= CLOCAL; - cfsetispeed(tp, ispeed); - cfsetospeed(tp, ospeed); - - tp->c_iflag = tp->c_lflag = 0; + tp->c_iflag = 0; + tp->c_lflag = 0; tp->c_oflag = OPOST | ONLCR; tp->c_cc[VMIN] = 1; tp->c_cc[VTIME] = 0; @@ -388,14 +403,14 @@ static char *get_logname(char *logname, unsigned size_logname, char *bp; char c; /* input character, full eight bits */ char ascval; /* low 7 bits of input character */ - int bits; /* # of "1" bits per character */ - int mask; /* mask with 1 bit up */ +#ifdef BROKEN_PARITY_DETECTION_CODE static const char erase[][3] = {/* backspace-space-backspace */ "\010\040\010", /* space parity */ "\010\040\010", /* odd parity */ "\210\240\210", /* even parity */ "\010\040\010", /* 8 bit no parity */ }; +#endif /* NB: *cp is pre-initialized with init_chardata */ @@ -406,14 +421,13 @@ static char *get_logname(char *logname, unsigned size_logname, /* Prompt for and read a login name. */ logname[0] = '\0'; while (!logname[0]) { - /* Write issue file and prompt, with "parity" bit == 0. */ + /* Write issue file and prompt. */ do_prompt(op); /* Read name, watch for break, parity, erase, kill, end-of-line. */ bp = logname; cp->eol = '\0'; - while (cp->eol == '\0') { - + while (1) { /* Do not report trivial EINTR/EIO errors. */ errno = EINTR; /* make read of 0 bytes be silent too */ if (read(STDIN_FILENO, &c, 1) < 1) { @@ -427,10 +441,11 @@ static char *get_logname(char *logname, unsigned size_logname, if (c == '\0' && op->numspeed > 1) return NULL; +#ifdef BROKEN_PARITY_DETECTION_CODE /* Do parity bit handling. */ - if (!(option_mask32 & F_LOCAL) && (c & 0x80)) { /* "parity" bit on? */ - bits = 1; - mask = 1; + if (!(option_mask32 & F_LOCAL) && (c & 0x80)) { /* "parity" bit on? */ + int bits = 1; + int mask = 1; while (mask & 0x7f) { if (mask & c) bits++; /* count "1" bits */ @@ -439,15 +454,18 @@ static char *get_logname(char *logname, unsigned size_logname, /* ... |= 2 - even, 1 - odd */ cp->parity |= 2 - (bits & 1); } + ascval = c & 0x7f; +#else + ascval = c; +#endif /* Do erase, kill and end-of-line processing. */ - ascval = c & 0x7f; switch (ascval) { case CR: case NL: *bp = '\0'; /* terminate logname */ cp->eol = ascval; /* set end-of-line char */ - break; + goto got_logname; case BS: case DEL: #ifdef ANCIENT_BS_KILL_CHARS @@ -455,17 +473,25 @@ static char *get_logname(char *logname, unsigned size_logname, #endif cp->erase = ascval; /* set erase character */ if (bp > logname) { +#ifdef BROKEN_PARITY_DETECTION_CODE full_write(STDOUT_FILENO, erase[cp->parity], 3); +#else + full_write(STDOUT_FILENO, "\010 \010", 3); +#endif bp--; } break; case CTL('U'): #ifdef ANCIENT_BS_KILL_CHARS case '@': -#endif cp->kill = ascval; /* set kill character */ +#endif while (bp > logname) { +#ifdef BROKEN_PARITY_DETECTION_CODE full_write(STDOUT_FILENO, erase[cp->parity], 3); +#else + full_write(STDOUT_FILENO, "\010 \010", 3); +#endif bp--; } break; @@ -474,19 +500,18 @@ static char *get_logname(char *logname, unsigned size_logname, default: if (ascval < ' ') { /* ignore garbage characters */ - } else if ((int)(bp - logname) >= size_logname - 1) { - bb_error_msg_and_die("input overrun"); - } else { + } else if ((int)(bp - logname) < size_logname - 1) { full_write(STDOUT_FILENO, &c, 1); /* echo the character */ *bp++ = ascval; /* and store it */ } break; } - } - } - /* Handle names with upper case and no lower case. */ + } /* end of get char loop */ + got_logname: ; + } /* while logname is empty */ #ifdef HANDLE_ALLCAPS + /* Handle names with upper case and no lower case. */ cp->capslock = all_is_upcase(logname); if (cp->capslock) { for (bp = logname; *bp; bp++) @@ -520,8 +545,13 @@ static void termios_final(struct termios *tp, struct chardata *cp) tp->c_oflag |= ONLCR; /* map NL in output to CR-NL */ } tp->c_cc[VERASE] = cp->erase; /* set erase character */ +#ifdef ANCIENT_BS_KILL_CHARS tp->c_cc[VKILL] = cp->kill; /* set kill character */ +#else + tp->c_cc[VKILL] = DEF_KILL; /* set kill character */ +#endif +#ifdef BROKEN_PARITY_DETECTION_CODE /* Account for the presence or absence of parity bits in input. */ switch (cp->parity) { case 0: /* space (always 0) parity */ @@ -542,17 +572,19 @@ static void termios_final(struct termios *tp, struct chardata *cp) // Entire parity detection madness here just begs for deletion... break; } +#endif - /* Account for upper case without lower case. */ #ifdef HANDLE_ALLCAPS + /* Account for upper case without lower case. */ if (cp->capslock) { tp->c_iflag |= IUCLC; tp->c_lflag |= XCASE; tp->c_oflag |= OLCUC; } #endif - /* Optionally enable hardware flow control */ + #ifdef CRTSCTS + /* Optionally enable hardware flow control */ if (option_mask32 & F_RTSCTS) tp->c_cflag |= CRTSCTS; #endif @@ -685,7 +717,7 @@ int getty_main(int argc UNUSED_PARAM, char **argv) logname = NULL; if (!(option_mask32 & F_NOPROMPT)) { - /* NB:termios_init already set line speed + /* NB: termios_init already set line speed * to options.speeds[0] */ int baud_index = 0; -- 2.25.1