Files
shadow/lib/loginprompt.c
2024-12-06 19:17:25 +01:00

109 lines
2.2 KiB
C

/*
* SPDX-FileCopyrightText: 1989 - 1993, Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 2000, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
* SPDX-FileCopyrightText: 2008 - 2011, Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include <assert.h>
#include <stdio.h>
#include <signal.h>
#include "attr.h"
#include "defines.h"
#include "getdef.h"
#include "prototypes.h"
#include "string/memset/memzero.h"
#include "string/strchr/stpspn.h"
#include "string/strcpy/strtcpy.h"
#include "string/strtok/stpsep.h"
static void login_exit (MAYBE_UNUSED int sig)
{
_exit (EXIT_FAILURE);
}
/*
* login_prompt - prompt the user for their login name
*
* login_prompt() displays the standard login prompt. If ISSUE_FILE
* is set in login.defs, this file is displayed before the prompt.
*/
void
login_prompt(char *name, int namesize)
{
char buf[1024];
char *cp;
int i;
FILE *fp;
const char *fname = getdef_str ("ISSUE_FILE");
sighandler_t sigquit;
sighandler_t sigtstp;
/*
* There is a small chance that a QUIT character will be part of
* some random noise during a prompt. Deal with this by exiting
* instead of core dumping. Do the same thing for SIGTSTP.
*/
sigquit = signal (SIGQUIT, login_exit);
sigtstp = signal (SIGTSTP, login_exit);
/*
* See if the user has configured the issue file to
* be displayed and display it before the prompt.
*/
if (NULL != fname) {
fp = fopen (fname, "r");
if (NULL != fp) {
while ((i = getc (fp)) != EOF) {
(void) putc (i, stdout);
}
(void) fclose (fp);
}
}
(void) gethostname (buf, sizeof buf);
printf (_("\n%s login: "), buf);
(void) fflush (stdout);
/*
* Read the user's response. The trailing newline will be
* removed.
*/
MEMZERO(buf);
if (fgets (buf, sizeof buf, stdin) != buf) {
exit (EXIT_FAILURE);
}
if (stpsep(buf, "\n") == NULL)
exit(EXIT_FAILURE);
/*
* Skip leading whitespace. This makes " username" work right.
* Then copy the rest (up to the end) into the username.
*/
cp = stpspn(buf, " \t");
strtcpy(name, cp, namesize);
/*
* Set the SIGQUIT handler back to its original value
*/
(void) signal (SIGQUIT, sigquit);
(void) signal (SIGTSTP, sigtstp);
}