1 /* $NetBSD: openpam_dlfunc.h,v 1.3 2017/05/06 19:50:09 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2013 Dag-Erling Smørgrav 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $OpenPAM: openpam_dlfunc.h 938 2017-04-30 21:34:42Z des $ 32 */ 33 34 #ifndef OPENPAM_DLFCN_H_INCLUDED 35 #define OPENPAM_DLFCN_H_INCLUDED 36 37 #ifndef HAVE_DLFUNC 38 /*- 39 * The actual type declared by this typedef is immaterial, provided that 40 * it is a function pointer. Its purpose is to provide a return type for 41 * dlfunc() which can be cast to a function pointer type without depending 42 * on behavior undefined by the C standard, which might trigger a compiler 43 * diagnostic. We intentionally declare a unique type signature to force 44 * a diagnostic should the application not cast the return value of dlfunc() 45 * appropriately. 46 */ 47 struct __dlfunc_arg { 48 int __dlfunc_dummy; 49 }; 50 51 typedef void (*dlfunc_t)(struct __dlfunc_arg); 52 53 static inline dlfunc_t 54 dlfunc(void *handle, const char *symbol) 55 { 56 57 return ((dlfunc_t)dlsym(handle, symbol)); 58 } 59 #endif 60 61 #endif 62