/* Copyright (C) 1992,93,94,95,96,97,98,99,2000, 2001 Free Software Foundation, Inc.   This file is part of the GNU C Library.   The GNU C Library is free software; you can redistribute it and/or   modify it under the terms of the GNU Library General Public License as   published by the Free Software Foundation; either version 2 of the   License, or (at your option) any later version.   The GNU C Library is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   Library General Public License for more details.   You should have received a copy of the GNU Library General Public   License along with the GNU C Library; see the file COPYING.LIB.  If not,   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,   Boston, MA 02111-1307, USA.  */#if HAVE_CONFIG_H# include <config.h>#endif#include <stdio.h>#include <termios.h>#include <unistd.h>#include "getline.h"#include "unlocked-io.h"/* It is desirable to use this bit on systems that have it.   The only bit of terminal state we want to twiddle is echoing, which is   done in software; there is no need to change the state of the terminal   hardware.  */#ifndef TCSASOFT# define TCSASOFT 0#endifchar *getpass (const char *prompt){  FILE *in, *out;  struct termios s, t;  int tty_changed;  static char *buf;  static size_t bufsize;  ssize_t nread;  /* Try to write to and read from the terminal if we can.     If we can't open the terminal, use stderr and stdin.  */  in = fopen ("/dev/tty", "w+");  if (in == NULL)    {      in = stdin;      out = stderr;    }  else    out = in;  /* Turn echoing off if it is on now.  */  if (tcgetattr (fileno (in), &t) == 0)    {      /* Save the old one. */      s = t;      /* Tricky, tricky. */      t.c_lflag &= ~(ECHO|ISIG);      tty_changed = (tcsetattr (fileno (in), TCSAFLUSH|TCSASOFT, &t) == 0);    }  else    tty_changed = 0;  /* Write the prompt.  */  fputs (prompt, out);  fflush (out);  /* Read the password.  */  nread = getline (&buf, &bufsize, in);  if (buf != NULL)    {      if (nread < 0)	buf[0] = '\0';      else if (buf[nread - 1] == '\n')	{	  /* Remove the newline.  */	  buf[nread - 1] = '\0';	  if (tty_changed)	    /* Write the newline that was not echoed.  */	    putc ('\n', out);	}    }  /* Restore the original setting.  */  if (tty_changed)    (void) tcsetattr (fileno (in), TCSAFLUSH|TCSASOFT, &s);  if (in != stdin)    /* We opened the terminal; now close it.  */    fclose (in);  return buf;}