1 /*- 2 * Copyright (c) 1998 John D. Polstra 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: src/lib/libc/gen/dlfcn.c 217154 2011-01-08 17:13:43Z kib $ 27 */ 28 29 #include <dlfcn.h> 30 #include <link.h> 31 #include <stddef.h> 32 33 void _rtld_error(const char *, ...); 34 35 static char sorry[] = "Service unavailable"; 36 37 /* 38 * For ELF, the dynamic linker directly resolves references to its 39 * services to functions inside the dynamic linker itself. These 40 * weak-symbol stubs are necessary so that "ld" won't complain about 41 * undefined symbols. The stubs are executed only when the program is 42 * linked statically, or when a given service isn't implemented in the 43 * dynamic linker. They must return an error if called, and they must 44 * be weak symbols so that the dynamic linker can override them. 45 */ 46 47 #pragma weak _rtld_error 48 void 49 _rtld_error(const char *fmt __unused, ...) 50 { 51 } 52 53 #pragma weak dladdr 54 int 55 dladdr(const void *addr __unused, Dl_info *dlip __unused) 56 { 57 _rtld_error(sorry); 58 return 0; 59 } 60 61 #pragma weak dlclose 62 int 63 dlclose(void *handle __unused) 64 { 65 _rtld_error(sorry); 66 return -1; 67 } 68 69 #pragma weak dlerror 70 char * 71 dlerror(void) 72 { 73 return sorry; 74 } 75 76 #pragma weak dlopen 77 void * 78 dlopen(const char *name __unused, int mode __unused) 79 { 80 _rtld_error(sorry); 81 return NULL; 82 } 83 84 #pragma weak dlsym 85 void * 86 dlsym(void *handle __unused, const char *name __unused) 87 { 88 _rtld_error(sorry); 89 return NULL; 90 } 91 92 #pragma weak dlfunc 93 dlfunc_t 94 dlfunc(void * handle __unused, const char * name __unused) 95 { 96 _rtld_error(sorry); 97 return NULL; 98 } 99 100 #pragma weak dlvsym 101 void * 102 dlvsym(void *handle __unused,const char *name __unused, 103 const char *version __unused) 104 { 105 _rtld_error(sorry); 106 return NULL; 107 } 108 109 #pragma weak dlinfo 110 int 111 dlinfo(void *handle __unused, int request __unused, void *p __unused) 112 { 113 _rtld_error(sorry); 114 return 0; 115 } 116 117 #pragma weak dl_iterate_phdr 118 int 119 dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *), 120 void *data) 121 { 122 _rtld_error(sorry); 123 return 0; 124 } 125 126 #pragma weak _rtld_addr_phdr 127 int 128 _rtld_addr_phdr(const void *addr, struct dl_phdr_info *phdr_info) 129 { 130 131 return (0); 132 } 133 134