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 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 *) 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 *) 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 *) 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) 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) 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