shadow/lib/fields.c
tomspiderlabs e5905c4b84 Added control character check
Added control character check, returning -1 (to "err") if control characters are present.
2023-03-30 19:23:00 -05:00

110 lines
2.2 KiB
C

/*
* SPDX-FileCopyrightText: 1990 , Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 1997, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2003 - 2005, Tomasz Kłoczko
* SPDX-FileCopyrightText: 2007 , Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include <ctype.h>
#include <string.h>
#include <stdio.h>
#include "prototypes.h"
/*
* valid_field - insure that a field contains all legal characters
*
* The supplied field is scanned for non-printable and other illegal
* characters.
* + -1 is returned if an illegal or control character is present.
* + 1 is returned if no illegal or control characters are present,
* but the field contains a non-printable character.
* + 0 is returned otherwise.
*/
int valid_field (const char *field, const char *illegal)
{
const char *cp;
int err = 0;
if (NULL == field) {
return -1;
}
/* For each character of field, search if it appears in the list
* of illegal characters. */
for (cp = field; '\0' != *cp; cp++) {
if (strchr (illegal, *cp) != NULL) {
err = -1;
break;
}
}
if (0 == err) {
/* Search if there are non-printable or control characters */
for (cp = field; '\0' != *cp; cp++) {
if (!isprint (*cp)) {
err = 1;
}
if (!iscntrl (*cp)) {
err = -1;
break;
}
}
}
return err;
}
/*
* change_field - change a single field if a new value is given.
*
* prompt the user with the name of the field being changed and the
* current value.
*/
void change_field (char *buf, size_t maxsize, const char *prompt)
{
char newf[200];
char *cp;
if (maxsize > sizeof (newf)) {
maxsize = sizeof (newf);
}
printf ("\t%s [%s]: ", prompt, buf);
(void) fflush (stdout);
if (fgets (newf, maxsize, stdin) != newf) {
return;
}
cp = strchr (newf, '\n');
if (NULL == cp) {
return;
}
*cp = '\0';
if ('\0' != newf[0]) {
/*
* Remove leading and trailing whitespace. This also
* makes it possible to change the field to empty, by
* entering a space. --marekm
*/
while (newf < cp && isspace (cp[-1])) {
cp--;
}
*cp = '\0';
cp = newf;
while (isspace (*cp)) {
cp++;
}
strcpy (buf, cp);
}
}