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 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 /* 31 * Linkage to services provided by the dynamic linker. 32 */ 33 #include <dlfcn.h> 34 #include <link.h> 35 #include <stddef.h> 36 37 static const char sorry[] = "Service unavailable"; 38 39 /* 40 * For ELF, the dynamic linker directly resolves references to its 41 * services to functions inside the dynamic linker itself. These 42 * weak-symbol stubs are necessary so that "ld" won't complain about 43 * undefined symbols. The stubs are executed only when the program is 44 * linked statically, or when a given service isn't implemented in the 45 * dynamic linker. They must return an error if called, and they must 46 * be weak symbols so that the dynamic linker can override them. 47 */ 48 49 #pragma weak _rtld_error 50 void 51 _rtld_error(const char *fmt, ...) 52 { 53 } 54 55 #pragma weak dladdr 56 int 57 dladdr(const void *addr, Dl_info *dlip) 58 { 59 _rtld_error(sorry); 60 return 0; 61 } 62 63 #pragma weak dlclose 64 int 65 dlclose(void *handle) 66 { 67 _rtld_error(sorry); 68 return -1; 69 } 70 71 #pragma weak dlerror 72 const char * 73 dlerror(void) 74 { 75 return sorry; 76 } 77 78 #pragma weak dllockinit 79 void 80 dllockinit(void *context, 81 void *(*lock_create)(void *context), 82 void (*rlock_acquire)(void *lock), 83 void (*wlock_acquire)(void *lock), 84 void (*lock_release)(void *lock), 85 void (*lock_destroy)(void *lock), 86 void (*context_destroy)(void *context)) 87 { 88 if (context_destroy != NULL) 89 context_destroy(context); 90 } 91 92 #pragma weak dlopen 93 void * 94 dlopen(const char *name, int mode) 95 { 96 _rtld_error(sorry); 97 return NULL; 98 } 99 100 #pragma weak dlsym 101 void * 102 dlsym(void * __restrict handle, const char * __restrict name) 103 { 104 _rtld_error(sorry); 105 return NULL; 106 } 107 108 #pragma weak dlvsym 109 void * 110 dlvsym(void * __restrict handle, const char * __restrict name, 111 const char * __restrict version) 112 { 113 _rtld_error(sorry); 114 return NULL; 115 } 116 117 #pragma weak dlinfo 118 int 119 dlinfo(void * __restrict handle, int request, void * __restrict p) 120 { 121 _rtld_error(sorry); 122 return 0; 123 } 124 125 #pragma weak _rtld_thread_init 126 void 127 _rtld_thread_init(void * li) 128 { 129 _rtld_error(sorry); 130 } 131 132 #pragma weak dl_iterate_phdr 133 int 134 dl_iterate_phdr(int (*callback)(struct dl_phdr_info *, size_t, void *), 135 void *data) 136 { 137 _rtld_error(sorry); 138 return 0; 139 } 140 141 #pragma weak _rtld_atfork_pre 142 void 143 _rtld_atfork_pre(int *locks) 144 { 145 } 146 147 #pragma weak _rtld_atfork_post 148 void 149 _rtld_atfork_post(int *locks) 150 { 151 } 152