1 /*------------------------------------------------------------------
2 * strfirstchar_s.c
3 *
4 * November 2008, Bo Berry
5 *
6 * Copyright (c) 2008-2011 by Cisco Systems, Inc
7 * All rights reserved.
8 *
9 * Permission is hereby granted, free of charge, to any person
10 * obtaining a copy of this software and associated documentation
11 * files (the "Software"), to deal in the Software without
12 * restriction, including without limitation the rights to use,
13 * copy, modify, merge, publish, distribute, sublicense, and/or
14 * sell copies of the Software, and to permit persons to whom the
15 * Software is furnished to do so, subject to the following
16 * conditions:
17 *
18 * The above copyright notice and this permission notice shall be
19 * included in all copies or substantial portions of the Software.
20 *
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
23 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
25 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
26 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28 * OTHER DEALINGS IN THE SOFTWARE.
29 *------------------------------------------------------------------
30 */
31
32 #include "safeclib_private.h"
33 #include "safe_str_constraint.h"
34 #include "safe_str_lib.h"
35
36
37 /**
38 * NAME
39 * strfirstchar_s
40 *
41 * SYNOPSIS
42 * #include "safe_str_lib.h"
43 * errno_t
44 * strfirstchar_s(char *dest, rsize_t dmax, char c, char **first)
45 *
46 * DESCRIPTION
47 * This function returns a pointer to the first occurrence
48 * of character c in dest. The scanning stops at the first null
49 * or after dmax characters.
50 *
51 * EXTENSION TO
52 * ISO/IEC TR 24731, Programming languages, environments
53 * and system software interfaces, Extensions to the C Library,
54 * Part I: Bounds-checking interfaces
55 *
56 * INPUT PARAMETERS
57 * dest pointer to string to compare against
58 *
59 * dmax restricted maximum length of string
60 *
61 * c character to locate
62 *
63 * first returned pointer to first occurrence of c
64 *
65 * OUTPUT PARAMETERS
66 * first updated pointer to first occurrence of c
67 *
68 * RUNTIME CONSTRAINTS
69 * dest shall not be a null pointer.
70 * first shall not be a null pointer.
71 * dmax shall not be 0
72 * dmax shall not be greater than RSIZE_MAX_STR
73 *
74 * RETURN VALUE
75 * pointer to first occurence of c, NULL if not found
76 *
77 * EOK pointer to first occurrence is returned
78 * ESNULLP NULL pointer
79 * ESZEROL zero length
80 * ESLEMAX length exceeds max limit
81 *
82 * ALSO SEE
83 * strlastchar_s(), strfirstdiff_s(), strfirstsame_s(),
84 * strlastdiff_s(), strlastsame_s(),
85 *
86 */
87 errno_t
strfirstchar_s(char * dest,rsize_t dmax,char c,char ** first)88 strfirstchar_s (char *dest, rsize_t dmax, char c, char **first)
89 {
90
91 if (first == NULL) {
92 invoke_safe_str_constraint_handler("strfirstchar_s: index is null",
93 NULL, ESNULLP);
94 return (ESNULLP);
95 }
96 *first = NULL;
97
98 if (dest == NULL) {
99 invoke_safe_str_constraint_handler("strfirstchar_s: dest is null",
100 NULL, ESNULLP);
101 return (ESNULLP);
102 }
103
104 if (dmax == 0 ) {
105 invoke_safe_str_constraint_handler("strfirstchar_s: dmax is 0",
106 NULL, ESZEROL);
107 return (ESZEROL);
108 }
109
110 if (dmax > RSIZE_MAX_STR) {
111 invoke_safe_str_constraint_handler("strfirstchar_s: dmax exceeds max",
112 NULL, ESLEMAX);
113 return (ESLEMAX);
114 }
115
116 while (*dest && dmax) {
117
118 if (*dest == c) {
119 *first = dest;
120 return (EOK);
121 }
122 dest++;
123 dmax--;
124 }
125
126 return (ESNOTFND);
127 }
128 EXPORT_SYMBOL(strfirstchar_s)
129