1 /*-
2 * SPDX-License-Identifier: BSD-1-Clause
3 *
4 * Copyright 2018 Andrew Turner
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
13 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
14 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
15 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
16 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
17 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
18 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
19 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
20 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
21 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
22 */
23
24 #include <sys/param.h>
25
26 #include "crt.h"
27
28 typedef void (*crt_func)(void);
29
30 extern void *__dso_handle __hidden;
31
32 #ifndef SHARED
33 void *__dso_handle = 0;
34 #else
35 void *__dso_handle = &__dso_handle;
36 void __cxa_finalize(void *) __weak_symbol;
37
38 /*
39 * Call __cxa_finalize with the dso handle in shared objects.
40 * When we have ctors/dtors call from the dtor handler before calling
41 * any dtors, otherwise use a destructor.
42 */
43 #ifndef HAVE_CTORS
44 __attribute__((destructor))
45 #endif
46 static void
run_cxa_finalize(void)47 run_cxa_finalize(void)
48 {
49
50 if (__cxa_finalize != NULL)
51 __cxa_finalize(__dso_handle);
52 }
53 #endif
54
55 /*
56 * On some architectures and toolchains we may need to call the .dtors.
57 * These are called in the order they are in the ELF file.
58 */
59 #ifdef HAVE_CTORS
60 static void __do_global_dtors_aux(void) __used;
61
62 static crt_func __CTOR_LIST__[] __section(".ctors") __used = {
63 (crt_func)-1
64 };
65 static crt_func __DTOR_LIST__[] __section(".dtors") __used = {
66 (crt_func)-1
67 };
68
69 extern const char startof_dtors[] __asm(".startof..dtors")
70 __weak_symbol __hidden;
71 extern const char sizeof_dtors[] __asm(".sizeof..dtors")
72 __weak_symbol __hidden;
73
74 static void
__do_global_dtors_aux(void)75 __do_global_dtors_aux(void)
76 {
77 crt_func fn;
78 uintptr_t dtors_end;
79 int n;
80
81 #ifdef SHARED
82 run_cxa_finalize();
83 #endif
84
85 dtors_end = (uintptr_t)&startof_dtors + (uintptr_t)&sizeof_dtors;
86 for (n = 1;; n++) {
87 fn = __DTOR_LIST__[n];
88 if (fn == (crt_func)0 || fn == (crt_func)-1 || (dtors_end > 0 &&
89 (uintptr_t)&__DTOR_LIST__[n] >= dtors_end))
90 break;
91 fn();
92 }
93 }
94
95 asm (
96 ".pushsection .fini \n"
97 "\t" INIT_CALL_SEQ(__do_global_dtors_aux) "\n"
98 ".popsection \n"
99 );
100 #endif
101