1 /*------------------------------------------------------------------
2 * strspn_s.c
3 *
4 * November 2008, Bo Berry
5 *
6 * Copyright (c) 2008-2011, 2013 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 * strspn_s
40 *
41 * SYNOPSIS
42 * #include "safe_str_lib.h"
43 * errno_t
44 * strspn_s(const char *dest, rsize_t dmax,
45 * const char *src, rsize_t slen, rsize_t *count)
46 *
47 * DESCRIPTION
48 * This function computes the prefix length of the string
49 * pointed to by dest which consists entirely of characters
50 * that are included from the string pointed to by src.
51 *
52 * EXTENSION TO
53 * ISO/IEC TR 24731, Programming languages, environments
54 * and system software interfaces, Extensions to the C Library,
55 * Part I: Bounds-checking interfaces
56 *
57 * INPUT PARAMETERS
58 * dest pointer to string to determine the prefix
59 *
60 * dmax restricted maximum length of string dest
61 *
62 * src pointer to exclusion string
63 *
64 * slen restricted maximum length of string src
65 *
66 * count pointer to a count variable that will be updated
67 * with the dest substring length
68 *
69 * OUTPUT PARAMETERS
70 * count updated count
71 *
72 * RUNTIME CONSTRAINTS
73 * Neither dest nor src shall be a null pointer.
74 * count shall not be a null pointer.
75 * dmax shall not be 0
76 * dmax shall not be greater than RSIZE_MAX_STR
77 *
78 * RETURN VALUE
79 * EOK count
80 * ESNULLP NULL pointer
81 * ESZEROL zero length
82 * ESLEMAX length exceeds max limit
83 *
84 * ALSO SEE
85 * strcspn_s(), strpbrk_s(), strstr_s(), strprefix_s()
86 *
87 */
88 errno_t
strspn_s(const char * dest,rsize_t dmax,const char * src,rsize_t slen,rsize_t * count)89 strspn_s (const char *dest, rsize_t dmax,
90 const char *src, rsize_t slen, rsize_t *count)
91 {
92 const char *scan2;
93 rsize_t smax;
94 bool match_found;
95
96 if (count== NULL) {
97 invoke_safe_str_constraint_handler("strspn_s: count is null",
98 NULL, ESNULLP);
99 return RCNEGATE(ESNULLP);
100 }
101 *count = 0;
102
103 if (dest == NULL) {
104 invoke_safe_str_constraint_handler("strspn_s: dest is null",
105 NULL, ESNULLP);
106 return RCNEGATE(ESNULLP);
107 }
108
109 if (src == NULL) {
110 invoke_safe_str_constraint_handler("strspn_s: src is null",
111 NULL, ESNULLP);
112 return RCNEGATE(ESNULLP);
113 }
114
115 if (dmax == 0 ) {
116 invoke_safe_str_constraint_handler("strspn_s: dmax is 0",
117 NULL, ESZEROL);
118 return RCNEGATE(ESZEROL);
119 }
120
121 if (dmax > RSIZE_MAX_STR) {
122 invoke_safe_str_constraint_handler("strspn_s: dmax exceeds max",
123 NULL, ESLEMAX);
124 return RCNEGATE(ESLEMAX);
125 }
126
127 if (slen == 0 ) {
128 invoke_safe_str_constraint_handler("strspn_s: slen is 0",
129 NULL, ESZEROL);
130 return RCNEGATE(ESZEROL);
131 }
132
133 if (slen > RSIZE_MAX_STR) {
134 invoke_safe_str_constraint_handler("strspn_s: slen exceeds max",
135 NULL, ESLEMAX);
136 return RCNEGATE(ESLEMAX);
137 }
138
139 while (*dest && dmax) {
140
141 /*
142 * Scan the entire src string for each dest character, counting
143 * inclusions.
144 */
145 match_found = false;
146 smax = slen;
147 scan2 = src;
148 while (*scan2 && smax) {
149
150 if (*dest == *scan2) {
151 match_found = true;
152 break;
153 }
154 scan2++;
155 smax--;
156 }
157
158 if (match_found) {
159 (*count)++;
160 } else {
161 break;
162 }
163
164 dest++;
165 dmax--;
166 }
167
168 return RCNEGATE(EOK);
169 }
170 EXPORT_SYMBOL(strspn_s)
171