crt0-common.c revision 1.14 1 /* $NetBSD: crt0-common.c,v 1.14 2016/06/07 12:07:35 joerg Exp $ */
2
3 /*
4 * Copyright (c) 1998 Christos Zoulas
5 * Copyright (c) 1995 Christopher G. Demetriou
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed for the
19 * NetBSD Project. See http://www.NetBSD.org/ for
20 * information about NetBSD.
21 * 4. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 *
35 * <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
36 */
37
38 #include <sys/cdefs.h>
39 __RCSID("$NetBSD: crt0-common.c,v 1.14 2016/06/07 12:07:35 joerg Exp $");
40
41 #include <sys/types.h>
42 #include <sys/exec.h>
43 #include <sys/syscall.h>
44 #include <machine/profile.h>
45 #include <stdlib.h>
46 #include <unistd.h>
47
48 #include "rtld.h"
49
50 extern int main(int, char **, char **);
51
52 #ifndef HAVE_INITFINI_ARRAY
53 extern void _init(void);
54 extern void _fini(void);
55 #endif
56 extern void _libc_init(void);
57
58 /*
59 * Arrange for _DYNAMIC to be weak and undefined (and therefore to show up
60 * as being at address zero, unless something else defines it). That way,
61 * if we happen to be compiling without -static but with without any
62 * shared libs present, things will still work.
63 */
64
65 __weakref_visible int rtld_DYNAMIC __weak_reference(_DYNAMIC);
66
67 #ifdef MCRT0
68 extern void monstartup(u_long, u_long);
69 extern void _mcleanup(void);
70 extern unsigned char __etext, __eprol;
71 #endif /* MCRT0 */
72
73 char **environ;
74 struct ps_strings *__ps_strings = 0;
75
76 static char empty_string[] = "";
77 char *__progname = empty_string;
78
79 __dead __dso_hidden void ___start(void (*)(void), const Obj_Entry *,
80 struct ps_strings *);
81
82 #define write(fd, s, n) __syscall(SYS_write, (fd), (s), (n))
83
84 #define _FATAL(str) \
85 do { \
86 write(2, str, sizeof(str)-1); \
87 _exit(1); \
88 } while (0)
89
90 #ifdef HAVE_INITFINI_ARRAY
91 /*
92 * If we are using INIT_ARRAY/FINI_ARRAY and we are linked statically,
93 * we have to process these instead of relying on RTLD to do it for us.
94 *
95 * Since we don't need .init or .fini sections, just code them in C
96 * to make life easier.
97 */
98 extern const fptr_t __preinit_array_start[] __dso_hidden;
99 extern const fptr_t __preinit_array_end[] __dso_hidden __weak;
100 extern const fptr_t __init_array_start[] __dso_hidden;
101 extern const fptr_t __init_array_end[] __dso_hidden __weak;
102 extern const fptr_t __fini_array_start[] __dso_hidden;
103 extern const fptr_t __fini_array_end[] __dso_hidden __weak;
104
105 static inline void
106 _preinit(void)
107 {
108 for (const fptr_t *f = __preinit_array_start; f < __preinit_array_end; f++) {
109 (*f)();
110 }
111 }
112
113 static inline void
114 _init(void)
115 {
116 for (const fptr_t *f = __init_array_start; f < __init_array_end; f++) {
117 (*f)();
118 }
119 }
120
121 static void
122 _fini(void)
123 {
124 for (const fptr_t *f = __fini_array_start; f < __fini_array_end; f++) {
125 (*f)();
126 }
127 }
128 #endif /* HAVE_INITFINI_ARRAY */
129
130 void
131 ___start(void (*cleanup)(void), /* from shared loader */
132 const Obj_Entry *obj, /* from shared loader */
133 struct ps_strings *ps_strings)
134 {
135
136 if (ps_strings == NULL)
137 _FATAL("ps_strings missing\n");
138 __ps_strings = ps_strings;
139
140 environ = ps_strings->ps_envstr;
141
142 if (ps_strings->ps_argvstr[0] != NULL) {
143 char *c;
144 __progname = ps_strings->ps_argvstr[0];
145 for (c = ps_strings->ps_argvstr[0]; *c; ++c) {
146 if (*c == '/')
147 __progname = c + 1;
148 }
149 } else {
150 __progname = empty_string;
151 }
152
153 if (&rtld_DYNAMIC != NULL) {
154 if (obj == NULL)
155 _FATAL("NULL Obj_Entry pointer in GOT\n");
156 if (obj->magic != RTLD_MAGIC)
157 _FATAL("Corrupt Obj_Entry pointer in GOT\n");
158 if (obj->version != RTLD_VERSION)
159 _FATAL("Dynamic linker version mismatch\n");
160 atexit(cleanup);
161 }
162
163 _libc_init();
164
165 #ifdef HAVE_INITFINI_ARRAY
166 _preinit();
167 #endif
168
169 #ifdef MCRT0
170 atexit(_mcleanup);
171 monstartup((u_long)&__eprol, (u_long)&__etext);
172 #endif
173
174 atexit(_fini);
175 _init();
176
177 exit(main(ps_strings->ps_nargvstr, ps_strings->ps_argvstr, environ));
178 }
179