check_utility_compat.c revision 114256
1/* 2 * Copyright 2002 Massachusetts Institute of Technology 3 * 4 * Permission to use, copy, modify, and distribute this software and 5 * its documentation for any purpose and without fee is hereby 6 * granted, provided that both the above copyright notice and this 7 * permission notice appear in all copies, that both the above 8 * copyright notice and this permission notice appear in all 9 * supporting documentation, and that the name of M.I.T. not be used 10 * in advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. M.I.T. makes 12 * no representations about the suitability of this software for any 13 * purpose. It is provided "as is" without express or implied 14 * warranty. 15 * 16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#include <sys/cdefs.h> 31__FBSDID("$FreeBSD: head/lib/libc/gen/check_utility_compat.c 114256 2003-04-29 21:13:50Z nectar $"); 32 33#include "namespace.h" 34#include <limits.h> 35#include <stdlib.h> 36#include <string.h> 37#include <unistd.h> 38#include "un-namespace.h" 39 40#ifndef LINE_MAX 41#define LINE_MAX _POSIX2_LINE_MAX 42#endif 43 44#define _PATH_UTIL_COMPAT "/etc/compat-FreeBSD-4-util" 45#define _ENV_UTIL_COMPAT "_COMPAT_FreeBSD_4" 46 47int 48check_utility_compat(const char *utility) 49{ 50 char buf[LINE_MAX]; 51 char *p, *bp; 52 int len; 53 54 if ((p = getenv(_ENV_UTIL_COMPAT)) != NULL) { 55 _strlcpy(buf, p, sizeof buf); 56 } else { 57 if ((len = readlink(_PATH_UTIL_COMPAT, buf, sizeof buf)) < 0) 58 return 0; 59 if (len > sizeof buf) 60 len = sizeof buf; 61 buf[len] = '\0'; 62 } 63 if (buf[0] == '\0') 64 return 1; 65 66 bp = buf; 67 while ((p = strsep(&bp, ",")) != NULL) { 68 if (strcmp(p, utility) == 0) 69 return 1; 70 } 71 return 0; 72} 73