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1/*
2 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
d7e50217 6 * Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b 7 *
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8 * This file contains Original Code and/or Modifications of Original Code
9 * as defined in and that are subject to the Apple Public Source License
10 * Version 2.0 (the 'License'). You may not use this file except in
11 * compliance with the License. Please obtain a copy of the License at
12 * http://www.opensource.apple.com/apsl/ and read it before using this
13 * file.
14 *
15 * The Original Code and all software distributed under the License are
16 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
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17 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
18 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
d7e50217
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19 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
20 * Please see the License for the specific language governing rights and
21 * limitations under the License.
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22 *
23 * @APPLE_LICENSE_HEADER_END@
24 */
25/*
26 * @OSF_FREE_COPYRIGHT@
27 */
28/*
29 * HISTORY
30 *
31 * Revision 1.1.1.1 1998/09/22 21:05:32 wsanchez
32 * Import of Mac OS X kernel (~semeria)
33 *
34 * Revision 1.1.1.1 1998/03/07 02:25:56 wsanchez
35 * Import of OSF Mach kernel (~mburg)
36 *
37 * Revision 1.1.8.2 1997/02/12 12:52:33 stephen
38 * New file, reimplemented to be sure of copyright status
39 * Initially only supports character matching and '%d'
40 * [1997/02/12 12:43:09 stephen]
41 *
42 * $EndLog$
43 */
44
45#include <stdarg.h>
46#include <kern/misc_protos.h>
47
48#define isdigit(c) ((unsigned) ((c) - '0') < 10U)
49
50/*
51 * Scan items from a string in accordance with a format. This is much
52 * simpler than the C standard function: it only recognises %d without a
53 * field width, and does not treat space in the format string or the
54 * input any differently from other characters. The return value is the
55 * number of characters from the input string that were successfully
56 * scanned, not the number of format items matched as in standard sscanf.
57 * e.mcmanus@opengroup.org, 12 Feb 97
58 */
59int
60sscanf(const char *str, const char *format, ...)
61{
62 const char *start = str;
63 va_list args;
64
65 va_start(args, format);
66 for ( ; *format != '\0'; format++) {
67 if (*format == '%' && format[1] == 'd') {
68 int positive;
69 int value;
70 int *valp;
71
72 if (*str == '-') {
73 positive = 0;
74 str++;
75 } else
76 positive = 1;
77 if (!isdigit(*str))
78 break;
79 value = 0;
80 do {
81 value = (value * 10) - (*str - '0');
82 str++;
83 } while (isdigit(*str));
84 if (positive)
85 value = -value;
86 valp = va_arg(args, int *);
87 *valp = value;
88 format++;
89 } else if (*format == *str) {
90 str++;
91 } else
92 break;
93 }
94 va_end(args);
95 return str - start;
96}