1 /*
2 * Copyright (C) 2008 The Android Open Source Project
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 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28 /*
29 * libc_init_static.c
30 *
31 * The program startup function __libc_init() defined here is
32 * used for static executables only (i.e. those that don't depend
33 * on shared libraries). It is called from arch-$ARCH/bionic/crtbegin_static.S
34 * which is directly invoked by the kernel when the program is launched.
35 *
36 * The 'structors' parameter contains pointers to various initializer
37 * arrays that must be run before the program's 'main' routine is launched.
38 */
39
40 #include <stddef.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <stdint.h>
44 #include <elf.h>
45 #include "pthread_internal.h"
46 #include "atexit.h"
47 #include "libc_init_common.h"
48
49 #include <bionic_tls.h>
50 #include <errno.h>
51
call_array(void (** list)())52 static void call_array(void(**list)())
53 {
54 // First element is -1, list is null-terminated
55 while (*++list) {
56 (*list)();
57 }
58 }
59
__libc_init(uintptr_t * elfdata,void (* onexit)(void),int (* slingshot)(int,char **,char **),structors_array_t const * const structors)60 __noreturn void __libc_init(uintptr_t *elfdata,
61 void (*onexit)(void),
62 int (*slingshot)(int, char**, char**),
63 structors_array_t const * const structors)
64 {
65 int argc;
66 char **argv, **envp;
67
68 __libc_init_tls(NULL);
69
70 /* Initialize the C runtime environment */
71 __libc_init_common(elfdata);
72
73 /* Several Linux ABIs don't pass the onexit pointer, and the ones that
74 * do never use it. Therefore, we ignore it.
75 */
76
77 /* pre-init array. */
78 call_array(structors->preinit_array);
79
80 // call static constructors
81 call_array(structors->init_array);
82
83 argc = (int) *elfdata;
84 argv = (char**)(elfdata + 1);
85 envp = argv + argc + 1;
86
87 /* The executable may have its own destructors listed in its .fini_array
88 * so we need to ensure that these are called when the program exits
89 * normally.
90 */
91 if (structors->fini_array)
92 __cxa_atexit(__libc_fini,structors->fini_array,NULL);
93
94 exit(slingshot(argc, argv, envp));
95 }
96