xref: /illumos-gate/usr/src/uts/common/krtld/kobj_subr.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 
30 #include <sys/bootconf.h>
31 #include <sys/kobj_impl.h>
32 #include <sys/cmn_err.h>
33 
34 /*
35  * Standalone utility functions for use within krtld.
36  * Many platforms implement optimized platmod versions of
37  * utilities such as bcopy and any such are not yet available
38  * until the kernel is more completely stitched together.
39  * These standalones are referenced through vectors
40  * kobj_bzero, etc.  Throughout krtld, the usual utility
41  * is redefined to reference through the corresponding
42  * vector so that krtld may simply refer to bzero etc.
43  * as usual.  See kobj_impl.h.
44  */
45 extern void vprintf(const char *, va_list);
46 
47 /*ARGSUSED*/
48 static void
49 vkprintf(void *op, const char *fmt, va_list adx)
50 {
51 	vprintf(fmt, adx);
52 }
53 
54 static void
55 kprintf(void *op, const char *fmt, ...)
56 {
57 	va_list adx;
58 
59 	va_start(adx, fmt);
60 	vkprintf(op, fmt, adx);
61 	va_end(adx);
62 }
63 
64 static void
65 stand_bzero(void *p_arg, size_t count)
66 {
67 	char zero = 0;
68 	caddr_t p = p_arg;
69 
70 	while (count != 0)
71 		*p++ = zero, count--;
72 }
73 
74 static void
75 stand_bcopy(const void *src_arg, void *dest_arg, size_t count)
76 {
77 	caddr_t src = (caddr_t)src_arg;
78 	caddr_t dest = dest_arg;
79 
80 	if (src < dest && (src + count) > dest) {
81 		/* overlap copy */
82 		while (--count != -1)
83 			*(dest + count) = *(src + count);
84 	} else {
85 		while (--count != -1)
86 			*dest++ = *src++;
87 	}
88 }
89 
90 static size_t
91 stand_strlcat(char *dst, const char *src, size_t dstsize)
92 {
93 	char *df = dst;
94 	size_t left = dstsize;
95 	size_t l1;
96 	size_t l2 = strlen(src);
97 	size_t copied;
98 
99 	while (left-- != 0 && *df != '\0')
100 		df++;
101 	l1 = df - dst;
102 	if (dstsize == l1)
103 		return (l1 + l2);
104 
105 	copied = l1 + l2 >= dstsize ? dstsize - l1 - 1 : l2;
106 	bcopy(src, dst + l1, copied);
107 	dst[l1+copied] = '\0';
108 	return (l1 + l2);
109 }
110 
111 /*
112  * Set up the krtld standalone utilty vectors
113  */
114 void
115 kobj_setup_standalone_vectors()
116 {
117 	_kobj_printf = bop_printf;
118 	_vkobj_printf = vbop_printf;
119 	kobj_bcopy = stand_bcopy;
120 	kobj_bzero = stand_bzero;
121 	kobj_strlcat = stand_strlcat;
122 }
123 
124 /*
125  * Restore the kprintf/vkprintf/bcopy/bzero kobj vectors.
126  * We need to undefine the override macros to
127  * accomplish this.
128  *
129  * Do NOT add new code after the point or at least
130  * certainly not code using bcopy or bzero which would
131  * need to be vectored to the krtld equivalents.
132  */
133 #undef	bcopy
134 #undef	bzero
135 #undef	strlcat
136 
137 void
138 kobj_restore_vectors()
139 {
140 	_kobj_printf = kprintf;
141 	_vkobj_printf = vkprintf;
142 	kobj_bcopy = bcopy;
143 	kobj_bzero = bzero;
144 	kobj_strlcat = strlcat;
145 }
146