shadow/libmisc/loginprompt.c

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/*
* Copyright 1989 - 1993, Julianne Frances Haugh
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Julianne F. Haugh nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JULIE HAUGH AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL JULIE HAUGH OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include <signal.h>
#include <ctype.h>
#include "prototypes.h"
#include "defines.h"
#include "getdef.h"
static void login_exit (int sig)
{
exit (1);
}
/*
* 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 (const char *prompt, char *name, int namesize)
{
char buf[1024];
#define MAX_ENV 32
char *envp[MAX_ENV];
int envc;
char *cp;
int i;
FILE *fp;
RETSIGTYPE (*sigquit) (int);
#ifdef SIGTSTP
RETSIGTYPE (*sigtstp) (int);
#endif
/*
* 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. If SIGTSTP is defined, do the same
* thing for that signal.
*/
sigquit = signal (SIGQUIT, login_exit);
#ifdef SIGTSTP
sigtstp = signal (SIGTSTP, login_exit);
#endif
/*
* See if the user has configured the issue file to
* be displayed and display it before the prompt.
*/
if (prompt) {
cp = getdef_str ("ISSUE_FILE");
if (cp && (fp = fopen (cp, "r"))) {
while ((i = getc (fp)) != EOF)
putc (i, stdout);
fclose (fp);
}
gethostname (buf, sizeof buf);
printf (prompt, buf);
fflush (stdout);
}
/*
* Read the user's response. The trailing newline will be
* removed.
*/
memzero (buf, sizeof buf);
if (fgets (buf, sizeof buf, stdin) != buf)
exit (1);
cp = strchr (buf, '\n');
if (!cp)
exit (1);
*cp = '\0'; /* remove \n [ must be there ] */
/*
* Skip leading whitespace. This makes " username" work right.
* Then copy the rest (up to the end or the first "non-graphic"
* character into the username.
*/
for (cp = buf; *cp == ' ' || *cp == '\t'; cp++);
for (i = 0; i < namesize - 1 && isgraph (*cp); name[i++] = *cp++);
while (isgraph (*cp))
cp++;
if (*cp)
cp++;
name[i] = '\0';
/*
* This is a disaster, at best. The user may have entered extra
* environmental variables at the prompt. There are several ways
* to do this, and I just take the easy way out.
*/
if (*cp != '\0') { /* process new variables */
char *nvar;
int count = 1;
for (envc = 0; envc < MAX_ENV; envc++) {
nvar = strtok (envc ? (char *) 0 : cp, " \t,");
if (!nvar)
break;
if (strchr (nvar, '=')) {
envp[envc] = nvar;
} else {
envp[envc] = xmalloc (strlen (nvar) + 32);
sprintf (envp[envc], "L%d=%s", count++, nvar);
}
}
set_env (envc, envp);
}
/*
* Set the SIGQUIT handler back to its original value
*/
signal (SIGQUIT, sigquit);
#ifdef SIGTSTP
signal (SIGTSTP, sigtstp);
#endif
}