1 /*
2 * Copyright (c) 1999-2010 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * Mach Operating System
30 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
31 * All Rights Reserved.
32 *
33 * Permission to use, copy, modify and distribute this software and its
34 * documentation is hereby granted, provided that both the copyright
35 * notice and this permission notice appear in all copies of the
36 * software, derivative works or modified versions, and any portions
37 * thereof, and that both notices appear in supporting documentation.
38 *
39 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
40 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
41 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
42 *
43 * Carnegie Mellon requests users of this software to return to
44 *
45 * Software Distribution Coordinator or [email protected]
46 * School of Computer Science
47 * Carnegie Mellon University
48 * Pittsburgh PA 15213-3890
49 *
50 * any improvements or extensions that they make and grant Carnegie Mellon
51 * the rights to redistribute these changes.
52 */
53 /*
54 * mig_strncpy.c - by Joshua Block
55 *
56 * mig_strncpy -- Bounded string copy. Does what the library routine strncpy
57 * OUGHT to do: Copies the (null terminated) string in src into dest, a
58 * buffer of length len. Assures that the copy is still null terminated
59 * and doesn't overflow the buffer, truncating the copy if necessary.
60 *
61 * Parameters:
62 *
63 * dest - Pointer to destination buffer.
64 *
65 * src - Pointer to source string.
66 *
67 * len - Length of destination buffer.
68 *
69 * Result:
70 * length of string copied, INCLUDING the trailing 0.
71 */
72 #include <mach/mig_errors.h>
73
74 int
mig_strncpy(char * dest,const char * src,int len)75 mig_strncpy(
76 char *dest,
77 const char *src,
78 int len)
79 {
80 int i;
81
82 if (len <= 0) {
83 return 0;
84 }
85
86 for (i = 1; i < len; i++) {
87 if (!(*dest++ = *src++)) {
88 return i;
89 }
90 }
91
92 *dest = '\0';
93 return i;
94 }
95
96 /*
97 * mig_strncpy_zerofill -- Bounded string copy. Does what the
98 * library routine strncpy OUGHT to do: Copies the (null terminated)
99 * string in src into dest, a buffer of length len. Assures that
100 * the copy is still null terminated and doesn't overflow the buffer,
101 * truncating the copy if necessary. If the string in src is smaller
102 * than given length len, it will zero fill the remaining bytes in dest.
103 *
104 * Parameters:
105 *
106 * dest - Pointer to destination buffer.
107 *
108 * src - Pointer to source string.
109 *
110 * len - Length of destination buffer.
111 *
112 * Result:
113 * length of string copied, INCLUDING the trailing 0.
114 */
115 int
mig_strncpy_zerofill(char * dest,const char * src,int len)116 mig_strncpy_zerofill(
117 char *dest,
118 const char *src,
119 int len)
120 {
121 int i;
122 boolean_t terminated = FALSE;
123 int retval = 0;
124
125 if (len <= 0 || dest == 0) {
126 return 0;
127 }
128
129 if (src == 0) {
130 terminated = TRUE;
131 }
132
133 for (i = 1; i < len; i++) {
134 if (!terminated) {
135 if (!(*dest++ = *src++)) {
136 retval = i;
137 terminated = TRUE;
138 }
139 } else {
140 *dest++ = '\0';
141 }
142 }
143
144 *dest = '\0';
145 if (!terminated) {
146 retval = i;
147 }
148
149 return retval;
150 }
151