diff options
Diffstat (limited to 'libc/unistd/getpass.c')
-rw-r--r-- | libc/unistd/getpass.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/libc/unistd/getpass.c b/libc/unistd/getpass.c new file mode 100644 index 000000000..4fcc489c8 --- /dev/null +++ b/libc/unistd/getpass.c @@ -0,0 +1,99 @@ +/* Copyright (C) 1992,93,94,95,96,97,98,99 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. */ + +#include <stdio.h> +#include <termios.h> +#include <unistd.h> +#include <string.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 +#endif +#define PWD_BUFFER_SIZE 256 + +char * +getpass (prompt) + const char *prompt; +{ + FILE *in, *out; + struct termios s, t; + int tty_changed; + static char buf[PWD_BUFFER_SIZE]; + int 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. */ + fgets (buf, PWD_BUFFER_SIZE-1, in); + nread = strlen(buf); + 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; +} |