1da2e3ebdSchin /*********************************************************************** 2da2e3ebdSchin * * 3da2e3ebdSchin * This software is part of the ast package * 4*b30d1939SAndy Fiddaman * Copyright (c) 1985-2012 AT&T Intellectual Property * 5da2e3ebdSchin * and is licensed under the * 6*b30d1939SAndy Fiddaman * Eclipse Public License, Version 1.0 * 77c2fbfb3SApril Chin * by AT&T Intellectual Property * 8da2e3ebdSchin * * 9da2e3ebdSchin * A copy of the License is available at * 10*b30d1939SAndy Fiddaman * http://www.eclipse.org/org/documents/epl-v10.html * 11*b30d1939SAndy Fiddaman * (with md5 checksum b35adb5213ca9657e911e9befb180842) * 12da2e3ebdSchin * * 13da2e3ebdSchin * Information and Software Systems Research * 14da2e3ebdSchin * AT&T Research * 15da2e3ebdSchin * Florham Park NJ * 16da2e3ebdSchin * * 17da2e3ebdSchin * Glenn Fowler <gsf@research.att.com> * 18da2e3ebdSchin * David Korn <dgk@research.att.com> * 19da2e3ebdSchin * Phong Vo <kpv@research.att.com> * 20da2e3ebdSchin * * 21da2e3ebdSchin ***********************************************************************/ 22da2e3ebdSchin #pragma prototyped 23da2e3ebdSchin 24da2e3ebdSchin #include <ast.h> 25da2e3ebdSchin 26da2e3ebdSchin #if _lib_readlink 27da2e3ebdSchin 28da2e3ebdSchin NoN(readlink) 29da2e3ebdSchin 30da2e3ebdSchin #else 31da2e3ebdSchin 32da2e3ebdSchin #include "fakelink.h" 33da2e3ebdSchin 34da2e3ebdSchin #include <error.h> 35da2e3ebdSchin 36da2e3ebdSchin #ifndef ENOSYS 37da2e3ebdSchin #define ENOSYS EINVAL 38da2e3ebdSchin #endif 39da2e3ebdSchin 40da2e3ebdSchin int 41da2e3ebdSchin readlink(const char* path, char* buf, int siz) 42da2e3ebdSchin { 43da2e3ebdSchin int fd; 44da2e3ebdSchin int n; 45da2e3ebdSchin 46da2e3ebdSchin if (siz > sizeof(FAKELINK_MAGIC)) 47da2e3ebdSchin { 48*b30d1939SAndy Fiddaman if ((fd = open(path, O_RDONLY|O_cloexec)) < 0) 49da2e3ebdSchin return -1; 50da2e3ebdSchin if (read(fd, buf, sizeof(FAKELINK_MAGIC)) == sizeof(FAKELINK_MAGIC) && !strcmp(buf, FAKELINK_MAGIC) && (n = read(fd, buf, siz)) > 0 && !buf[n - 1]) 51da2e3ebdSchin { 52da2e3ebdSchin close(fd); 53da2e3ebdSchin return n; 54da2e3ebdSchin } 55da2e3ebdSchin close(fd); 56da2e3ebdSchin } 57da2e3ebdSchin errno = ENOSYS; 58da2e3ebdSchin return -1; 59da2e3ebdSchin } 60da2e3ebdSchin 61da2e3ebdSchin #endif 62