xref: /openbsd-src/lib/csu/crt0.c (revision 505a4c3431df84a171fd8fa30b28616439059ae7)
1 /*	$OpenBSD: crt0.c,v 1.18 2023/07/27 18:17:14 kettenis Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Christopher G. Demetriou
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *      This product includes software developed by Christopher G. Demetriou
18  *	for the NetBSD Project.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/syscall.h>
35 #include <stdlib.h>
36 #include <limits.h>
37 
38 #include "md_init.h"
39 #ifdef RCRT0
40 # include BOOT_H
41 #endif
42 #include "extern.h"
43 
44 #define STR(x) __STRING(x)	/* shorter macro name for MD_RCRT0_START */
45 
46 /* some defaults */
47 #ifndef	MD_START_ARGS
48 #define	MD_START_ARGS	\
49 	int argc, char **argv, char **envp, void (*cleanup)(void)
50 #endif
51 static void		___start(MD_START_ARGS) __used;
52 #ifndef	MD_EPROL_LABEL
53 #define	MD_EPROL_LABEL	__asm("  .text\n_eprol:")
54 #endif
55 #ifndef RCRT0_RELRO
56 #define RCRT0_RELRO()	do {} while (0)
57 #endif
58 
59 char	***_csu_finish(char **_argv, char **_envp, void (*_cleanup)(void));
60 
61 #ifdef MCRT0
62 #include <sys/gmon.h>
63 extern __dso_hidden unsigned char _etext, _eprol;
64 #endif /* MCRT0 */
65 
66 #ifdef RCRT0
67 #ifdef MD_RCRT0_START
68 MD_RCRT0_START;
69 #endif
70 #else
71 #ifdef MD_CRT0_START
72 MD_CRT0_START;
73 #endif
74 #endif
75 
76 extern __dso_hidden initarray_f __preinit_array_start[],
77 	__preinit_array_end[], __init_array_start[], __init_array_end[];
78 
79 extern char __csu_do_fini_array __dso_hidden;
80 
81 static void
___start(MD_START_ARGS)82 ___start(MD_START_ARGS)
83 {
84 	size_t size, i;
85 	char ***environp;
86 #ifdef MD_START_SETUP
87 	MD_START_SETUP
88 #endif
89 
90 	environp = _csu_finish(argv, envp, cleanup);
91 
92 #ifndef RCRT0
93 	if (cleanup == NULL) {
94 #endif
95 		size = __preinit_array_end - __preinit_array_start;
96 		for (i = 0; i < size; i++)
97 			__preinit_array_start[i](argc, argv, envp, NULL);
98 		RCRT0_RELRO();
99 		size = __init_array_end - __init_array_start;
100 		for (i = 0; i < size; i++)
101 			__init_array_start[i](argc, argv, envp, NULL);
102 		__csu_do_fini_array = 1;
103 #ifndef RCRT0
104 	}
105 #endif
106 
107 #ifdef MCRT0
108 	atexit(_mcleanup);
109 	_monstartup((u_long)&_eprol, (u_long)&_etext);
110 #endif
111 
112 	__init();
113 
114 	exit(main(argc, argv, *environp));
115 }
116 
117 #ifdef MCRT0
118 MD_EPROL_LABEL;
119 #endif
120