1 /* $OpenBSD: strings.c,v 1.5 2023/10/17 09:52:09 nicm Exp $ */
2
3 /****************************************************************************
4 * Copyright 2020,2023 Thomas E. Dickey *
5 * Copyright 2000-2012,2017 Free Software Foundation, Inc. *
6 * *
7 * Permission is hereby granted, free of charge, to any person obtaining a *
8 * copy of this software and associated documentation files (the *
9 * "Software"), to deal in the Software without restriction, including *
10 * without limitation the rights to use, copy, modify, merge, publish, *
11 * distribute, distribute with modifications, sublicense, and/or sell *
12 * copies of the Software, and to permit persons to whom the Software is *
13 * furnished to do so, subject to the following conditions: *
14 * *
15 * The above copyright notice and this permission notice shall be included *
16 * in all copies or substantial portions of the Software. *
17 * *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
21 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
24 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
25 * *
26 * Except as contained in this notice, the name(s) of the above copyright *
27 * holders shall not be used in advertising or otherwise to promote the *
28 * sale, use or other dealings in this Software without prior written *
29 * authorization. *
30 ****************************************************************************/
31
32 /****************************************************************************
33 * Author: Thomas E. Dickey *
34 ****************************************************************************/
35
36 /*
37 ** lib_mvcur.c
38 **/
39
40 #include <curses.priv.h>
41 #include <tic.h>
42
43 MODULE_ID("$Id: strings.c,v 1.5 2023/10/17 09:52:09 nicm Exp $")
44
45 /****************************************************************************
46 * Useful string functions (especially for mvcur)
47 ****************************************************************************/
48
49 #if !HAVE_STRSTR
NCURSES_EXPORT(char *)50 NCURSES_EXPORT(char *)
51 _nc_strstr(const char *haystack, const char *needle)
52 {
53 size_t len1 = strlen(haystack);
54 size_t len2 = strlen(needle);
55 char *result = 0;
56
57 while ((len1 != 0) && (len1-- >= len2)) {
58 if (!strncmp(haystack, needle, len2)) {
59 result = (char *) haystack;
60 break;
61 }
62 haystack++;
63 }
64 return result;
65 }
66 #endif
67
68 /*
69 * Initialize the descriptor so we can append to it. Note that 'src' may
70 * be a null pointer (see _nc_str_null), so the corresponding strcat and
71 * strcpy calls have to allow for this.
72 */
73 NCURSES_EXPORT(string_desc *)
_nc_str_init(string_desc * dst,char * src,size_t len)74 _nc_str_init(string_desc * dst, char *src, size_t len)
75 {
76 if (dst != 0) {
77 dst->s_head = src;
78 dst->s_tail = src;
79 dst->s_size = len - 1;
80 dst->s_init = dst->s_size;
81 if (src != 0)
82 *src = 0;
83 }
84 return dst;
85 }
86
87 /*
88 * Initialize the descriptor for only tracking the amount of memory used.
89 */
90 NCURSES_EXPORT(string_desc *)
_nc_str_null(string_desc * dst,size_t len)91 _nc_str_null(string_desc * dst, size_t len)
92 {
93 return _nc_str_init(dst, 0, len);
94 }
95
96 /*
97 * Copy a descriptor
98 */
99 NCURSES_EXPORT(string_desc *)
_nc_str_copy(string_desc * dst,const string_desc * const src)100 _nc_str_copy(string_desc * dst, const string_desc * const src)
101 {
102 *dst = *src;
103 return dst;
104 }
105
106 /*
107 * Replaces strcat into a fixed buffer, returning false on failure.
108 */
109 NCURSES_EXPORT(bool)
_nc_safe_strcat(string_desc * dst,const char * src)110 _nc_safe_strcat(string_desc * dst, const char *src)
111 {
112 if (PRESENT(src)) {
113 size_t len = strlen(src);
114
115 if (len < dst->s_size) {
116 if (dst->s_tail != 0) {
117 _nc_STRCPY(dst->s_tail, src, dst->s_size);
118 dst->s_tail += len;
119 }
120 dst->s_size -= len;
121 return TRUE;
122 }
123 }
124 return FALSE;
125 }
126
127 /*
128 * Replaces strcpy into a fixed buffer, returning false on failure.
129 */
130 NCURSES_EXPORT(bool)
_nc_safe_strcpy(string_desc * dst,const char * src)131 _nc_safe_strcpy(string_desc * dst, const char *src)
132 {
133 if (PRESENT(src)) {
134 size_t len = strlen(src);
135
136 if (len < dst->s_size) {
137 if (dst->s_head != 0) {
138 _nc_STRCPY(dst->s_head, src, dst->s_size);
139 dst->s_tail = dst->s_head + len;
140 }
141 dst->s_size = dst->s_init - len;
142 return TRUE;
143 }
144 }
145 return FALSE;
146 }
147