2 * Copyright (c) 1998 John D. Polstra
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/lib/libc/gen/dlfcn.c 217154 2011-01-08 17:13:43Z kib $
35 extern char **environ
;
37 static char sorry
[] = "Service unavailable";
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.
49 #pragma weak _rtld_error
51 _rtld_error(const char *fmt __unused
, ...)
57 dladdr(const void *addr __unused
, Dl_info
*dlip __unused
)
65 dlclose(void *handle __unused
)
80 dlopen(const char *name __unused
, int mode __unused
)
88 dlsym(void *handle __unused
, const char *name __unused
)
96 dlfunc(void * handle __unused
, const char * name __unused
)
104 dlvsym(void *handle __unused
,const char *name __unused
,
105 const char *version __unused
)
111 #pragma weak _rtld_thread_init
113 _rtld_thread_init(void * li
)
120 dlinfo(void *handle __unused
, int request __unused
, void *p __unused
)
126 __dso_hidden
struct dl_phdr_info
127 build_phdr_info(void)
129 struct dl_phdr_info phdr_info
;
131 Elf_Auxinfo
*aux
, *auxp
;
134 sp
= (Elf_Addr
*) environ
;
137 aux
= (Elf_Auxinfo
*) sp
;
138 memset (&phdr_info
, 0, sizeof(phdr_info
));
139 for (auxp
= aux
; auxp
->a_type
!= AT_NULL
; auxp
++) {
140 switch (auxp
->a_type
) {
142 phdr_info
.dlpi_addr
= (Elf_Addr
) auxp
->a_un
.a_ptr
;
145 phdr_info
.dlpi_name
= (const char *) auxp
->a_un
.a_ptr
;
148 phdr_info
.dlpi_phdr
= (const Elf_Phdr
*) auxp
->a_un
.a_ptr
;
151 phdr_info
.dlpi_phnum
= (Elf_Half
) auxp
->a_un
.a_val
;
156 for (i
= 0; i
< phdr_info
.dlpi_phnum
; i
++)
157 if (phdr_info
.dlpi_phdr
[i
].p_type
== PT_TLS
) {
158 phdr_info
.dlpi_tls_modid
= 1;
159 phdr_info
.dlpi_tls_data
=
160 (void*)phdr_info
.dlpi_phdr
[i
].p_vaddr
;
166 #pragma weak dl_iterate_phdr
168 dl_iterate_phdr(int (*callback
)(struct dl_phdr_info
*, size_t, void *),
172 static struct dl_phdr_info phdr_info
;
175 phdr_info
= build_phdr_info();
178 return callback(&phdr_info
, sizeof(phdr_info
), data
);
183 fdlopen(int fd __unused
, int mode __unused
)
189 #pragma weak _rtld_addr_phdr
191 _rtld_addr_phdr(const void *addr __unused
,
192 struct dl_phdr_info
*phdr_info __unused
)
198 #pragma weak _rtld_get_stack_prot
200 _rtld_get_stack_prot(void)
202 return (PROT_EXEC
| PROT_READ
| PROT_WRITE
);