1/*********************************************************************** 2* * 3* This software is part of the ast package * 4* Copyright (c) 1985-2012 AT&T Intellectual Property * 5* and is licensed under the * 6* Eclipse Public License, Version 1.0 * 7* by AT&T Intellectual Property * 8* * 9* A copy of the License is available at * 10* http://www.eclipse.org/org/documents/epl-v10.html * 11* (with md5 checksum b35adb5213ca9657e911e9befb180842) * 12* * 13* Information and Software Systems Research * 14* AT&T Research * 15* Florham Park NJ * 16* * 17* Glenn Fowler <gsf@research.att.com> * 18* David Korn <dgk@research.att.com> * 19* Phong Vo <kpv@research.att.com> * 20* * 21***********************************************************************/ 22#pragma prototyped 23 24#include <ast.h> 25 26#if _lib_readlink 27 28NoN(readlink) 29 30#else 31 32#include "fakelink.h" 33 34#include <error.h> 35 36#ifndef ENOSYS 37#define ENOSYS EINVAL 38#endif 39 40int 41readlink(const char* path, char* buf, int siz) 42{ 43 int fd; 44 int n; 45 46 if (siz > sizeof(FAKELINK_MAGIC)) 47 { 48 if ((fd = open(path, O_RDONLY|O_cloexec)) < 0) 49 return -1; 50 if (read(fd, buf, sizeof(FAKELINK_MAGIC)) == sizeof(FAKELINK_MAGIC) && !strcmp(buf, FAKELINK_MAGIC) && (n = read(fd, buf, siz)) > 0 && !buf[n - 1]) 51 { 52 close(fd); 53 return n; 54 } 55 close(fd); 56 } 57 errno = ENOSYS; 58 return -1; 59} 60 61#endif 62